Author: "Alexandre Karpov" - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Alexandre Karpov"' showing total 59 results

Start Over Author "Alexandre Karpov"

59 results on '"Alexandre Karpov"'

1. Superconductive Ultracompact Magnetically Coupled Resonator With Twin-Spiral Structure

Author: Alexander P. Zhuravel, Alexey V. Ustinov, Alexandre Karpov, A. S. Averkin, Valery P. Koshelets, Steven M. Anlage, and Lyudmila V. Filippenko
Subjects: Coupling, Superconductivity, Materials science, HFSS, business.industry, Physics::Optics, Metamaterial, Resonance, 02 engineering and technology, Dielectric, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Inductive coupling, Electronic, Optical and Magnetic Materials, Resonator, Optics, 0103 physical sciences, Electrical and Electronic Engineering, 010306 general physics, 0210 nano-technology, business
Abstract: We describe a practical design of an ultracompact on-chip superconductive microresonator as a potential magnetic element of metamaterial. The achieved resonator size with respect to the wavelength in our experiment is about λ /14 400. The resonator consists of two superconducting Nb spirals, sandwiched face to face, with a small gap filled with dielectric. The spirals are turning in opposite directions: one clockwise, another counterclockwise. We study the resonator spectral response and its inner modes using numerical simulation in HFSS. In experiment with a laser scanning microscope, we confirm the predictions for the resonance frequencies of Nb superconductive resonator and its inner modes structures. Small size and the ease of manufacturing make the two-spiral resonator an attractive solution for superconductive filters, coupling circuits, and as a magnetic component of a metamaterial.
Published: 2017
Full Text: View/download PDF

2. Phase-sensitive imaging of microwave currents in superconductive circuits

Author: Alexey V. Ustinov, Alexandre Karpov, V. I. Chichkov, Alexander P. Zhuravel, and A. S. Averkin
Subjects: Materials science, Physics and Astronomy (miscellaneous), Phase (waves), FOS: Physical sciences, Applied Physics (physics.app-ph), 02 engineering and technology, 01 natural sciences, Signal, law.invention, Superconductivity (cond-mat.supr-con), Resonator, Optics, law, 0103 physical sciences, Electronics, Electronic circuit, 010302 applied physics, business.industry, Condensed Matter - Superconductivity, Physics - Applied Physics, 021001 nanoscience & nanotechnology, Laser, Modulation, 0210 nano-technology, business, Microwave
Abstract: The contemporary superconductive electronics is widely using planar circuits with micrometer-scale elements for a variety of applications. With the rise of complexity of a circuit and increased number of its components, a simple impedance measurement are often not efficient for diagnostics of problems, nor for clarifying the physics underlying the circuit response. The established Scanning Laser Microscope (LSM) technique generates the micrometer-scale images of the amplitude of the microwave currents in a planar superconductive circuit, but not the phase of the oscillating currents. Here we present a novel, more powerful type of LSM imaging containing the signal phase information. We employ a fast optical modulator in order to synchronize the phase of the laser intensity oscillation with the phase of the probing microwave signal. The loss induced in laser illuminated area strongly depends on the phase difference between the RF probing signal and the laser beam modulation. We explain the detection principle of the phase sensitive LSM and experimentally demonstrate the capability of this method using superconductive microwave resonators. The described technique facilitates understanding of complex RF current distributions in superconductive circuits., Comment: 8 pages, 4 figures
Published: 2019
Full Text: View/download PDF

3. Low Noise 1 THz SIS Mixer for Stratospheric Observatory: Design and Characterization

Author: J. A. Stern, Alexandre Karpov, Imran Mehdi, B. Bumble, Robert Lin, David Alan Miller, Henry G. LeDuc, and Jonas Zmuidzinas
Subjects: Physics, Infrared astronomy, Noise measurement, business.industry, Terahertz radiation, Slot antenna, Far-infrared astronomy, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, law.invention, Telescope, Observatory, law, Optoelectronics, Electrical and Electronic Engineering, business, Noise (radio)
Abstract: We report the development of a low noise SIS mixer aimed for 1 THz channel of the Caltech Airborne Submillimeter Interstellar Medium Investigations Receiver (CASIMIR), designed for the Stratospheric Observatory for Far Infrared Astronomy (SOFIA). The mixer uses Nb/Al-AlN/NbTiN SIS junctions with critical current density of about 45 kA/cm2. The junctions are shaped in order to optimize the suppression of the Josephson DC currents. We used a double slot planar antenna to couple the mixer chip with the telescope beam. The RF matching microcircuit is made using Nb and gold films. The mixer IF circuit is designed to cover 4-8 GHz band. The test receiver with the new mixer has the low noise operation in a 0.9-1.05 THz band. The minimum DSB receiver noise measured at 1 THz is 260 K (Y=1.64) , apparently the lowest reported up to date.
Published: 2011
Full Text: View/download PDF

4. Quantum Metamaterials Based on Nonlinear Superconducting Resonators

Author: Alexandre Karpov
Subjects: Superconductivity, Quantum optics, Physics, Laser scanning, business.industry, Physics::Medical Physics, Physics::Optics, Metamaterial, law.invention, SQUID, Resonator, Optics, law, Scanning SQUID microscopy, Condensed Matter::Superconductivity, business, Quantum
Abstract: We will present experimental study of SQUID array based quantum superconductive metamaterials. The cryogenic Laser Scanning Microscope technique gives an insight to confirm a coherent response of the SQUID-based microwave resonator arrays and its tunability.
Published: 2015
Full Text: View/download PDF

5. Broadband sample holder for microwave spectroscopy of superconducting qubits

Author: A. S. Averkin, Evgeni Il'ichev, Alexandre Karpov, N. N. Abramov, U. Huebner, K. V. Shulga, Evgenii Glushkov, and Alexey V. Ustinov
Subjects: Superconductivity, Cryostat, Flux qubit, Materials science, Condensed matter physics, Condensed Matter - Mesoscale and Nanoscale Physics, business.industry, Amplifier, Condensed Matter - Superconductivity, Bolometer, FOS: Physical sciences, law.invention, Superconductivity (cond-mat.supr-con), Interference (communication), law, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Optoelectronics, business, Instrumentation, Passband, Microwave
Abstract: We present a practical design and implementation of a broadband sample holder suitable for microwave experiments with superconducting integrated circuits at millikelvin temperatures. Proposed design can be easily integrated in standard dilution cryostats, has flat pass band response in a frequency range from 0 to 32 GHz, allowing the RF testing of the samples with substrate size up to 4x4 mm. The parasitic higher modes interference in the holder structure is analyzed and prevented via design considerations. The developed setup can be used for characterization of superconducting parametric amplifiers, bolometers and qubits. We tested the designed sample holder by characterizing of a superconducting flux qubit at 20 mK temperature., 11 pages, 7 figures
Published: 2014

6. A 200-300 GHz single sideband SIS mixer for radio astronomy

Author: Alexandre Karpov, K. H. Gundlach, D. Billon-Pierron, and J. Blondel
Subjects: Physics, Noise temperature, business.industry, Niobium, chemistry.chemical_element, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, Radio telescope, Optics, chemistry, Broadband, Electrical and Electronic Engineering, business, Compatible sideband transmission, Frequency mixer, Band rejection, Radio astronomy
Abstract: We present an ultra broadband low noise single sideband (SSB) SIS mixer developed for 200-300 GHz radio astronomy receivers. The mixer uses two Nb/AlO/sub x//Nb junctions. Image band rejection by 20 dB is provided in the entire 200-300 GHz band using a mechanical tuning of the single noncontacting backshort in the mixer. The SIS receiver SSB noise temperature is close to 50 K in the main part of the band. A speed-up of the observations at radio telescopes by a factor 2-3 is expected with the new receiver.
Published: 2001
Full Text: View/download PDF

7. Processing and characterization of high Jc NbN superconducting tunnel junctions for THz analog circuits and RSFQ

Author: Alexandre Karpov, F. Miletto-Granozio, J.-C. Villegier, V. Larrey, and M. Salez
Subjects: Superconductivity, Materials science, Condensed matter physics, Terahertz radiation, business.industry, Sputter deposition, Condensed Matter Physics, Epitaxy, Electronic, Optical and Magnetic Materials, Tunnel junction, Rapid single flux quantum, Chemical-mechanical planarization, Optoelectronics, Electrical and Electronic Engineering, business, Sheet resistance
Abstract: A generic NbN Superconducting Tunnel Junctions (STJ) technology has been developed using conventional substrates (Si and SOI-SIMOX) for making THz spectrometers including SIS receivers and RSFQ logic gates. NbN/MgO/NbN junctions with area of 1 /spl mu/m/sup 2/, Jc of 10 kA/cm/sup 2/ and low sub-gap leakage current (Vm>25 mV) are currently obtained from room temperature sputtered multilayers followed by a post-annealing at 250/spl deg/C. Using a thin MgO buffer layer deposited underneath the NbN electrodes, ensures lower NbN surface resistance values (Rs=7 /spl mu//spl Omega/) at 10 GHz and 4 K. Epitaxial NbN [100] films on MgO [100] with high gap frequency (1.4 THz) have also been achieved under the same deposition conditions at room temperature. The NbN SIS has shown good I-V photon induced steps when LO pumped at 300 GHz. We have developed an 8 levels Al/NbN multilayer process for making 1.5 THz SIS mixers (including Al antennas) on Si membranes patterned in SOI-SIMOX. Using the planarization techniques developed at the Si-MOS CEA-LETI Facility, we have also demonstrated on the possibility of extending our NbN technology to high level RSFQ circuit integration with 0.5 /spl mu/m/sup 2/ junction area, made on large area substrates (up to 8 inches).
Published: 1999
Full Text: View/download PDF

8. A three photon noise SIS heterodyne receiver at submillimeter wavelength

Author: M. Voss, J. Blondel, Alexandre Karpov, and K. H. Gundlach
Subjects: Physics, Noise temperature, business.industry, Superheterodyne receiver, Condensed Matter Physics, Submillimetre astronomy, Electronic, Optical and Magnetic Materials, law.invention, Radio telescope, Optics, law, Heterodyne detection, Electrical and Electronic Engineering, business, Compatible sideband transmission, Noise (radio), Radio astronomy
Abstract: An ultra-low noise single sideband SIS receiver has been prepared for radio astronomy at the sub millimeter wavelength /spl lambda//spl ap/0.85 mm. The minimum single sideband receiver noise temperature of 48 K corresponds to 3 h/spl omega//k or equivalent number of 3 photon of noise. The minimum single sideband SIS mixer noise temperature is about 20 K, close to 1.2 h/spl omega//k, or one photon of noise. The Nb/AlOx/Nb junctions with a Josephson critical current density of 9 KA/cm/sup 2/ and with the area of about 0.9 /spl mu/m/sup 2/ were used. The receiver has been tested at the 30 meter IRAM radio telescope in the winter seasons of 1997 and 1998. The observations at the radio telescope are speeded up by a factor of two to three with the new receiver.
Published: 1999
Full Text: View/download PDF

9. A broad band low noise SIS radiometer

Author: Valery P. Koshelets, Alexandre Karpov, J. Blondel, and P. Dmitriev
Subjects: Josephson effect, Heterodyne, Physics, Noise temperature, Radiometer, business.industry, Amplifier, Condensed Matter Physics, Low-noise amplifier, Electronic, Optical and Magnetic Materials, Optics, Intermediate frequency, Millimeter, Electrical and Electronic Engineering, business
Abstract: A new type of ultra broad band SIS low noise radiometer has been developed. The SIS receiver instantaneous band of about 30% is significantly increased compared to traditional designs. We avoid a restriction related to the limited band of the Intermediate Frequency (IF) low noise amplifier by using a multifrequency heterodyne power source. In this regime the frequency mixing is performed simultaneously in a big number of the subbands and the IF signals are combined in a common amplifier. A low noise operation in this regime is possible due to the quantum nature of the frequency mixing in SIS quasi particle tunnel junctions. The SIS receiver covers 25 GHz band centered at 90 GHz with an equivalent noise temperature of about 50 K. The receiver uses a fixed tuned SIS mixer with Nb/Al Ox/Nb junctions. The critical Josephson current density is about 2.6 KA/cm/sup 2/ and the junction area is of about 1.5 /spl mu/m/sup 2/. The limits to further improvement of the radiometer and the possibilities for extension of the technique to the sub millimeter band are discussed.
Published: 1999
Full Text: View/download PDF

10. Optimising receivers for ground-based millimetre wave radiotelescopes

Author: Alexandre Karpov
Subjects: Radio telescope, Computer science, Institut de radioastronomie millimétrique, General Physics and Astronomy, Millimeter, General Chemistry, Sensitivity (electronics), Noise (radio), Millimetre wave, Remote sensing
Abstract: We present a study of requirements on the sensitivity of millimetre and submillimetre wave receivers for application in radioastronomy. The study is based on the experience of operation of the SIS receivers at the radiotelescopes of the Institut de Radioastronomie Millimetrique (IRAM) and considers also the conditions of operation at future radio-astronomical instruments such as Large Southern Array (LSA), Millimetre Array (MMA) and Large Millimetre and Submillimetre Array (LMSA). As a compromise between receiver development efforts and system performance, we introduce the criterion of an ‘optimm’ receiver noise.
Published: 1999
Full Text: View/download PDF

11. [Untitled]

Author: J. Blondel, K. H. Gundlach, D. Billon-Pierron, M. Carter, and Alexandre Karpov
Subjects: Physics, Radiation, Radio receiver design, business.industry, Local oscillator, Schottky diode, Condensed Matter Physics, Vector processor, Radio telescope, Optics, Cardinal point, Power dividers and directional couplers, Electrical and Electronic Engineering, business, Instrumentation, Radio astronomy
Abstract: The integration of many receiver units into a receiver array is a common method of improvement of imaging systems. This approach, well known in the mm band for Schottky mixer arrays, has not so far been developed for Superconductor - Insulator - Superconductor (SIS) junction mixers, which give the best sensitivity in the short mm wave range and in the submm range. We demonstrate for the first time a practical low noise multibeam receiver module using SIS mixer technology. The basis for the integration of several SIS mixers with a common local oscillator source is given by the saturation of the SIS receiver noise dependence upon local oscillator power. The module comprises three identical SIS mixers integrated with a common local oscillator, coupled through a three branch waveguide directional coupler. The multibeam module has been developed for a focal plane array receiver of the 30 meter radio telescope of the Institut de Radioastronomie Millimetrique (IRAM).
Published: 1998
Full Text: View/download PDF

12. Noise and gain in frequency mixers with NbN SIS junctions

Author: J. Blondel, S. Takada, Alexandre Karpov, K. H. Gundlach, Masahiro Aoyagi, B. Plathner, and M. Schicke
Subjects: Materials science, business.industry, Terahertz radiation, Condensed Matter Physics, Junction area, Noise (electronics), Omega, Electronic, Optical and Magnetic Materials, Low noise, Wavelength, Optoelectronics, Millimeter, Electrical and Electronic Engineering, business, Sensitivity (electronics)
Abstract: We study noise and conversion gain in the SIS mixers with Nb/MgO/NbN junctions at the millimeter and submillimeter wavelengths in order to estimate the possibility to extent the low noise operation towards the theoretical limit of 4/spl Delta//h=2.4 THz. We present as preliminary result the lowest achieved receiver noise with NbN SIS junctions of 65 K with conversion gain of -6 dB at 162 GHz and 230 K receiver noise with conversion gain of -10 dB at 306 GHz. The junction area is 2 /spl mu/m/sup 2/ and Josephson critical current density is 1.4 KA/cm/sup 2/. The optimum R/sub N//spl omega/C of NbN junction for mixers is estimated as 600 GHz/V. In preliminary tests the junctions R/sub N//spl omega/C is 10-20 time superior to the optimum and a significant improvement of NbN SIS mixers may be expected. The noise sources in the NbN SIS junctions are studied and a possible mixer sensitivity improvement is discussed. The thermal properties of the SIS NbN are studied. The frequency limit of the low loss integrated tuning structure in NbN is estimated as at least as 1.5 THz.
Published: 1997
Full Text: View/download PDF

13. A 125-180 GHz fixed-tuned SIS mixer for radioastronomy

Author: P. Pasturel, Alexandre Karpov, J. Blondel, and K. H. Gundlach
Subjects: Physics, Noise temperature, Noise-figure meter, business.industry, Instrumentation, Mixer noise, Electrical engineering, Y-factor, Noise figure, Condensed Matter Physics, Noise floor, Electronic, Optical and Magnetic Materials, Low noise, Radio telescope, Optics, Josephson current, Phase noise, Optoelectronics, Flicker noise, Electrical and Electronic Engineering, business, Noise (radio)
Abstract: An ultra low noise fixed-tuned SIS mixer covering an instantaneous band of 45% around 150 GHz has been developed for radioastronomy. A new type of coplanar tuning circuit for the SIS junction is introduced. The Nb/Al oxide/Nb junctions are 2 /spl mu/m/sup 2/ with critical Josephson current density of 4.2 KA/cm/sup 2/. The minimum DSB mixer noise is 11 K. The minimum DSB receiver noise is 19 K, while the average noise is 25 K in the 130-175 GHz range with a 1 GHz IF band. A speedup of the observations by a factor 2-3 is possible with the new receiver at 30 m IRAM radiotelescope.
Published: 1997
Full Text: View/download PDF

14. Low noise SIS mixer for 230 GHz receivers of plateau de bure interferometer

Author: K. H. Gundlach, D. Billion-Pierron, J. Blondel, and Alexandre Karpov
Subjects: Physics, Superconductivity, Waveguide (electromagnetism), Radiation, business.industry, Circuit design, Quantum limit, Plateau de Bure Interferometer, Condensed Matter Physics, Bruit, Optics, Thermal, medicine, Electrical and Electronic Engineering, medicine.symptom, business, Instrumentation, Noise (radio)
Abstract: We present a SIS mixer developed for 200 – 250 GHz band receivers of Plateau de Bure Interferometer. We demonstrate the minimum DSB receiver noise of 20 K at 220 GHz. The average receiver noise of 25 K is possible in 200 – 250 GHz range. The receiver conversion gain and output noise instability of 10−4 on the time scale of 1 minute is comparable with the Shottky receivers performance. The minimum measured SIS mixer noise of about 10 K is close to the quantum limit. The waveguide SIS mixer with a single backshort has two junction array with inductively tuned junctions. The Nb/Al Oxide/Nb SIS junctions are 2.24 µm2 each with the Josephson critical current density of 3.2 KA/cm2. The thermal properties of the SIS mixer are studied. The mixer band of the low noise operation is in a good agreement with the design requirements.
Published: 1997
Full Text: View/download PDF

15. Ultra-compact superconductive resonator with double-spiral structure

Author: Alexander P. Zhuravel, Alexey V. Ustinov, Alexandre Karpov, Steven M. Anlage, and A. S. Averkin
Subjects: Superconductivity, Wavelength, Resonator, Optics, Dielectric resonator antenna, Materials science, Computer simulation, business.industry, Physics::Optics, Metamaterial, business, Helical resonator, Spiral
Abstract: We discuss the characteristics of an ultra-compact double-spiral superconductive Nb microresonator as a potential magnetic metamaterial element. This resonator consists of two superconducting Nb spirals, sandwiched face to face, with a small gap. We study the resonator spectral response by using numerical simulation. The resonator modal structure has been also examined with a laser scanning microscope. The achieved resonator size with respect to the wavelength in our experiment is about λ/4200. Compared to the single-spiral resonator, the frequency of the fundamental mode of the double-spiral one is lowered by a factor of six. Small size and the ease of manufacturing make the double-spiral resonator an attractive solution for magnetic the component of a metamaterial.
Published: 2013
Full Text: View/download PDF

16. Imaging the electromagnetic response of superconducting metasurfaces

Author: Alexey V. Ustinov, R. Kosarev, L. V. Filippenko, P. Jung, Valery P. Koshelets, Alexander P. Zhuravel, Alexandre Karpov, and S. Butz
Subjects: Superconductivity, Materials science, Condensed matter physics, business.industry, Electromagnetic response, Characterization (materials science), law.invention, Split-ring resonator, Planar, Laser scanning microscope, Optical microscope, law, Optoelectronics, business, Microwave metamaterials
Abstract: We present a method to analyze the electromagnetic behavior of superconducting planar microwave metamaterials. Using a laser scanning microscope (LSM), we image the microwave response of two-dimensional arrays of magnetic meta-atoms. This method allows us to investigate contributions of individual meta-atoms to the macroscopic response and thus provides a useful tool for characterization and optimization. The meta-atoms in the present experiment are frequency tunable superconducting quantum interference devices (SQUIDs).
Published: 2013
Full Text: View/download PDF

17. Dual-channel sis receivers for the iram Plateau de Bure Interferometer

Author: B. Lazareff, J. Blondel, Alexandre Karpov, James W. Lamb, F. Mattiocco, and M. Carter
Subjects: Physics, Radiation, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Phase (waves), Plateau de Bure Interferometer, Condensed Matter Physics, Chopper, Optics, Very-long-baseline interferometry, Calibration, Electrical and Electronic Engineering, Antenna (radio), business, Instrumentation, Sensitivity (electronics), Noise (radio), Computer Science::Information Theory
Abstract: The five antennas of the Plateau de Bure Interferometer have been instrumented with dual-channel receivers in the λ 3 mm and λ 1 mm bands. Polarisation diplexing allows simultaneous observations in the two bands. Each receiver has ambient and cryogenic calibration loads, and one receiver is equipped with a beam switching chopper for total power flux measurements. Typically the receiver noise temperatures are
Published: 1996
Full Text: View/download PDF

18. Low noise submillimeter SIS receiver with niobium nitride quasiparticle tunnel junctions

Author: Alexandre Karpov, S. Takada, J. Blondel, K. H. Gundlach, Masahiro Aoyagi, B. Plathner, and M. Schicke
Subjects: Superconductivity, Radiation, Materials science, Niobium nitride, business.industry, Condensed Matter Physics, law.invention, Low noise, chemistry.chemical_compound, Printed circuit board, chemistry, law, Tunnel junction, Quasiparticle, Optoelectronics, Electrical and Electronic Engineering, business, Instrumentation, Waveguide, Voltage
Abstract: We have developed and tested a submillimeter waveguide SIS mixer with NbN-MgO-NbN quasiparticle tunnel junctions. The two junction array is integrated in a full NbN printed circuit. The NbN film critical temperature is 15 K and the junction gap voltage is 5 mV. The size of the junctions is 1.4 × 1.4 µm and Josephson critical current density is about 1.5 KA/cm2 resulting in junction RNωC product about 40. The inductive tuning circuit in NbN is integrated with each junction in two junction array. A single non contacting backshort was tuned at each frequency in the mixer block.
Published: 1996
Full Text: View/download PDF

19. Noise and thermal properties of a submillimeter mixer with the SINS tunnel junction

Author: B. Lazareff, Alexandre Karpov, K. H. Gundlach, J. Blondel, and D. Maier
Subjects: Physics, Superconductivity, Radiation, business.industry, Condensed Matter Physics, Magnetic field, Quality (physics), Tunnel junction, Limit (music), Thermal, Optoelectronics, Electrical and Electronic Engineering, business, Instrumentation, Frequency mixer, Noise (radio)
Abstract: In this work we present for the first time a low-noise submillimeter receiver with a mixer using Superconductor-Insulator-Normal metal-Superconductor (SINS) junctions. Junctions containing a normal metal layer may be free of the Josephson current and of the related perturbations of mixer operation specific for the standard SIS mixers. This SINS mixer quality is important for the application in the multibeam submillimeter receiver. The SINS mixer stability of operation and independence on the magnetic field have been confirmed in our experiment. Minimum SINS receiver noise in the 290 – 330 GHz band is about 135 K when the junction RNωC is about 30. Noise, conversion gain and thermal properties of the SINS mixer have been studied and compared with the SIS mixers. The limit of SINS mixer operation improvement is discussed at the end of the work.
Published: 1995
Full Text: View/download PDF

20. Superconductor‐insulator‐normal conductor tunnel junctions for frequency mixing around 300 GHz

Author: K. H. Gundlach, Alexandre Karpov, T. Lehnert, and D. Maier
Subjects: Aluminium oxides, Superconductivity, Noise temperature, Materials science, Sideband, Physics::Instrumentation and Detectors, business.industry, Band gap, General Physics and Astronomy, Insulator (electricity), Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Conductor, Tunnel effect, Condensed Matter::Superconductivity, Optoelectronics, business
Abstract: Properties of superconductor‐insulator‐normal conductor tunnel junctions made from Nb‐Al/ Aloxide‐Al trilayers are described. These devices were successfully employed as quasiparticle mixers. The lowest double sideband receiver noise temperature in the 290–320 GHz band was about 140 K. The Nb wiring, which also defines the tuning circuit of the mixer, induces a small energy gap in the Al counter electrode at a physical temperature of 2.2 K.
Published: 1995
Full Text: View/download PDF

21. Four photons sensitivity heterodyne detection of submillimeter radiation with superconducting tunnel junctions

Author: J. Blondel, K. H. Gundlach, M. Voss, and Alexandre Karpov
Subjects: Physics, Noise temperature, Sideband, Terahertz radiation, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, law.invention, Telescope, Radio telescope, Optics, law, Heterodyne detection, Electrical and Electronic Engineering, Compatible sideband transmission, business, Noise (radio)
Abstract: An ultra low noise SIS receiver has been prepared for radio astronomy. The minimum double sideband receiver noise temperature is about 30 K which corresponds to 2 /spl planck//spl omega//k or an equivalent number of 4 photons of noise. The minimum measured double sideband mixer noise temperature is about 10 K which corresponds to 0.6 /spl planck//spl omega//k or approximately to 1 photon of noise. The fixed tuned SIS mixer operates in the 290-370 GHz frequency range. The submicron niobium junctions mere fabricated using photoresist lines for junction definition. The receiver has been used at the 30 m IRAM radio telescope in Spain in winter 1994. Telescope system noise temperature of 500 K single sideband has been achieved when the sky opacity was about 0.17. >
Published: 1995
Full Text: View/download PDF

22. Double‐barrier tunnel junctions for quasiparticle mixers

Author: D. Billon-Pierron, M. Rosengarten, T. Lehnert, H. Rothermel, Alexandre Karpov, and K. H. Gundlach
Subjects: Materials science, Condensed matter physics, Annealing (metallurgy), London penetration depth, Niobium, General Physics and Astronomy, chemistry.chemical_element, Magnetic field, Tunnel effect, chemistry, Condensed Matter::Superconductivity, Electrode, Quasiparticle, Irradiation
Abstract: Double‐barrier niobium tunnel junctions with the middle electrode thinner than the London penetration depth were fabricated. Their I‐V curves, annealing behavior, response to external magnetic field, and response to 230 and 350 GHz irradiation in mixer experiments is discussed. Junctions with an integrated tuning circuit designed for the 230 GHz frequency range gave double‐sideband receiver noise temperatures of 100 K. Vertically stack arrays can be attractive for various applications. Compared to single‐barrier devices possible drawbacks were noted. The I‐V curve indicates heating and/or nonequilibrium effects. Double‐barrier devices became nonuniform after thermal annealing at 200 °C. The response to the external magnetic field is more complex and considerably larger flux densities are needed to suppress Josephson effects.
Published: 1994
Full Text: View/download PDF

23. Submicron Nb-Al-oxide-Nb junctions for frequency mixers

Author: M. Voss, K. H. Gundlach, and Alexandre Karpov
Subjects: Fabrication, Materials science, business.industry, Local oscillator, Metals and Alloys, Photoresist, Condensed Matter Physics, law.invention, Resist, Tunnel junction, law, Materials Chemistry, Ceramics and Composites, Optoelectronics, Electrical and Electronic Engineering, Photolithography, business, Current density, Voltage
Abstract: A fabrication process for submicron Nb-Al-oxide-Nb tunnel junctions using photoresist lines and optical lithography is described. With 0.6 mu m wide resist lines, junction areas of about 0.4 mu m2 were obtained. At present the maximum current density obtainable is 8500 A cm-2, and for this the best Vm parameters of the submicron junctions are 47 mV at 4.2 K and 150 mV at 2.5 K. Compared with standard photoresist pads for junction definition, photoresist lines are more stable and result in junction areas closer to the areas on the mask. A weak increase of the gap voltage with decreasing junction size is observed. Finally, the performance of a 345 GHz receiver incorporating a two-junction array with integrated filter and tuning circuit is discussed.
Published: 1993
Full Text: View/download PDF

24. Detection of OH+ and H2O+ towards Orion KL

Author: Maryvonne Gerin, G. A. Blake, J. Stutzki, Shanshan Yu, S. Wang, Paul Hartogh, D. Johnstone, Thomas F. Giesen, Goutam Chattopadhyay, M. Perault, José Cernicharo, Ryszard Szczerba, Rudolf Schieder, Fabien Daniel, S. D. Lord, Jonas Zmuidzinas, Rafael Bachiller, Nathan R. Crockett, Alexandre Karpov, Neal R. Erickson, William B. Latter, John Gill, N. Harada, C. Joblin, P. Zaal, Marie-Lise Dubernet, Erich Schlecht, David A. Neufeld, P. F. Goldsmith, J. A. Murphy, René Liseau, Eric Herbst, C. Comito, Neil Trappe, H. Gupta, E. A. Bergin, A. C. A. Boogert, D. C. Lis, J. R. Goicoechea, Michael Olberg, Jacob Kooi, Jean-Michel Krieg, Frank Maiwald, W. Baechtold, Laurent Pagani, H. W. Yorke, T. A. Bell, F. F. S. van der Tak, Peter Schilke, Martin Emprechtinger, Cecilia Ceccarelli, Volker Ossenkopf, Stephan Schlemmer, Bengt Larsson, Paul B. Rimmer, W. D. Langer, P. J. Encrenaz, R. H. Lin, S.-L. Qin, N. Honingh, J. C. Pearson, Pierrick Martin, M. Salez, S. Cabrit, Emmanuel Caux, Thomas G. Phillips, Karl M. Menten, Sébastien Maret, Rene Plume, Patrick W. Morris, M. C. Diez-Gonzalez, Jesús Martín-Pintado, L. Nordh, Lorene Samoska, R. Güsten, Holger S. P. Müller, Charlotte Vastel, E. Falgarone, Gary J. Melnick, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Ohio State university Departement of Physic, Colombus, Ohio State University [Columbus] (OSU), Ohio State university Departement of Astronomy, Colombus, Ohio State university Departement of Chemistry, Colombus, foreign laboratories (FL), CERN [Genève], Ohio State Univ, Dept Phys, Columbus, OH 43210 USA, Ohio State Univ, Dept Astron & Chem, Columbus, OH 43210 USA, Ohio State University Dept Chemistry, Department of Astronomy [Ann Arbor], University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Millimeter-Wave Electronics Laboratory [ETH Zürich] (MWE), Department of Information Technology and Electrical Engineering [Zürich] (D-ITET), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Laboratoire Optimisation de la Conception et Ingénierie de l'Environnement (LOCIE), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), CNRS INSU, UMR 5187, F-31028 Toulouse 4, France, UMR 5187 Toulouse, Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Max Planck Institute for Radio Astronomy, Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL), Laboratoire de Radioastronomie (LRA), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Cahill Center for Astronomy and Astrophysics, California Institute of Technology (CALTECH), Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC V9E 2E7 Canada, Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, Laboratoire de Modélisation Multi-échelles des Combustibles (LM2C), Service d'Etudes de Simulation du Comportement du combustibles (SESC), Département d'Etudes des Combustibles (DEC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Département d'Etudes des Combustibles (DEC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Max-Planck-Institut für Radioastronomie (MPIFR), Infrared Processing and Analysis Center (IPAC), Onsala Space Observatory, Chalmers University of Technology [Göteborg], Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), SRON Netherlands Institute for Space Research (SRON), Department of Physics and Astronomy [Calgary], University of Calgary, I. Physikalisches Institut [Köln], Universität zu Köln = University of Cologne, Laboratoire de Didactique André Revuz (LDAR (EA_4434)), Université d'Artois (UA)-Université Paris Diderot - Paris 7 (UPD7)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, A.M.Obukhov Institute of Atmospheric Physics (IAP), Russian Academy of Sciences [Moscow] (RAS), Harvard University [Cambridge]-Smithsonian Institution, Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA, CALTECH, Ctr Infrared Proc & Anal, Pasadena, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Universität zu Köln, Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université Paris Diderot - Paris 7 (UPD7)-Université d'Artois (UA), Max-Planck-Institut für Sonnensystemforschung (MPS), Department of Physics [Columbus], Department of Astronomy [Columbus], Department chemistry and Biochemistry [Columbus], Department of Physics and Astronomy [Baltimore], Johns Hopkins University (JHU), Smithsonian Institution-Harvard University [Cambridge], Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Instituto Nacional de Técnica Aeroespacial (INTA), Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Observatorio de Yebes, Instituto Geografico Nacional (IGN), Laboratoire de Physique Moleculaire pour l'Atmosphere et l'Astrophysique (LPMAA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid 28850, Spain, Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), CEA-Direction de l'Energie Nucléaire (CEA-DEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction de l'Energie Nucléaire (CEA-DEN), Univ Cologne, Inst Phys 1, D-50937 Cologne, Germany, Univ Cologne, Inst Phys 1, and Astronomy
Subjects: [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], HERSCHEL OBSERVATIONS, Analytical chemistry, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, LINE, Astrophysics, LASER MAGNETIC-RESONANCE, 7. Clean energy, 01 natural sciences, ISM: abundances, outflows, Ion, STAR-FORMATION, REGION, NEBULA, Ionization, 0103 physical sciences, Absorption (logic), 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, SPECTROSCOPY, astrochemistry, Astronomy and Astrophysics, INTERSTELLAR H3O+, Astrophysics - Astrophysics of Galaxies, DIFFUSE CLOUDS, molecular processes, [PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], 13. Climate action, Space and Planetary Science, COMET-KOHOUTEK, Astrophysics of Galaxies (astro-ph.GA), stars: winds, submillimeter: ISM, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Order of magnitude, line: identification
Abstract: We report observations of the reactive molecular ions OH$^+$, H$_2$O$^+$, and H$_3$O$^+$ towards Orion KL with Herschel/HIFI. All three $N=1-0$ fine-structure transitions of OH$^+$ at 909, 971, and 1033GHz and both fine-structure components of the doublet {\it ortho}-H$_2$O$^+$ $1_{11}-0_{00}$ transition at 1115 and 1139GHz were detected; an upper limit was obtained for H$_3$O$^+$. OH$^+$ and H$_2$O$^+$ are observed purely in absorption, showing a narrow component at the source velocity of 9 kms$^{-1}$, and a broad blueshifted absorption similar to that reported recently for HF and {\it para}-H$_{2}^{18}$O, and attributed to the low velocity outflow of Orion KL. We estimate column densities of OH$^+$ and H$_2$O$^+$ for the 9 km s$^{-1}$ component of $9 \pm 3 \times 10^{12}$cm$^{-2}$ and $7 \pm 2 \times 10^{12}$cm$^{-2}$, and those in the outflow of $1.9 \pm 0.7 \times 10^{13}$cm$^{-2}$ and $1.0 \pm 0.3 \times 10^{13}$cm$^{-2}$. Upper limits of $2.4\times 10^{12}$cm$^{-2}$ and $8.7\times 10^{12}$cm$^{-2}$ were derived for the column densities of {\it ortho} and {\it para}-H$_3$O$^+$ from transitions near 985 and 1657GHz. The column densities of the three ions are up to an order of magnitude lower than those obtained from recent observations of W31C and W49N. The comparatively low column densities may be explained by a higher gas density despite the assumption of a very high ionization rate., 5 pages, 1 figure. Accepted to and to be published in the Herschel HIFI special issue of A\&A Letters
Published: 2010
Full Text: View/download PDF

25. Herschel observations of extra-ordinary sources: Detection of Hydrogen Fluoride in absorption towards Orion~KL

Author: T. A. Bell, E. A. Bergin, J. A. Murphy, Martin Emprechtinger, A. C. A. Boogert, S. D. Lord, Alexandre Karpov, D. C. Lis, P. J. Encrenaz, Neil Trappe, Cecilia Ceccarelli, Gary J. Melnick, S.-L. Qin, Rene Plume, D. Johnstone, Marie-Lise Dubernet, N. Honingh, H. W. Yorke, M. Perault, José Cernicharo, R. Güsten, Paul Hartogh, J. R. Goicoechea, Charlotte Vastel, Jean-Michel Krieg, W. D. Latter, Pierrick Martin, J. Stutzki, Jacob Kooi, Thomas G. Phillips, Emmanuel Caux, Holger S. P. Müller, Sébastien Maret, J. C. Pearson, C. Joblin, Karl M. Menten, Maryvonne Gerin, Rudolf Schieder, Jonas Zmuidzinas, Nathan R. Crockett, Eric Herbst, Fabien Daniel, F. F. S. van der Tak, G. A. Blake, Shanshan Yu, David A. Neufeld, P. F. Goldsmith, Volker Ossenkopf, Patrick W. Morris, Thomas F. Giesen, C. Comito, S. Wang, Peter Schilke, Stephan Schlemmer, W. D. Langer, Astronomy, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Faure, Alexandre
Subjects: Experimental Physics, Hydrogen, FOS: Physical sciences, Rotational transition, chemistry.chemical_element, Astrophysics, 01 natural sciences, ISM: abundances, chemistry.chemical_compound, 0103 physical sciences, Absorption (electromagnetic radiation), 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, Line-of-sight, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], 010308 nuclear & particles physics, Astronomy and Astrophysics, Hydrogen fluoride, Astrophysics - Astrophysics of Galaxies, Redshift, ISM: molecules, 3. Good health, chemistry, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Fluorine, submillimeter: ISM, Outflow
Abstract: We report a detection of the fundamental rotational transition of hydrogen fluoride in absorption towards Orion KL using Herschel/HIFI. After the removal of contaminating features associated with common molecules ("weeds"), the HF spectrum shows a P-Cygni profile, with weak redshifted emission and strong blue-shifted absorption, associated with the low-velocity molecular outflow. We derive an estimate of 2.9 x 10^13 cm^-2 for the HF column density responsible for the broad absorption component. Using our best estimate of the H2 column density within the low-velocity molecular outflow, we obtain a lower limit of ~1.6 x 10^-10 for the HF abundance relative to hydrogen nuclei, corresponding to 0.6% of the solar abundance of fluorine. This value is close to that inferred from previous ISO observations of HF J=2--1 absorption towards Sgr B2, but is in sharp contrast to the lower limit of 6 x 10^-9 derived by Neufeld et al. (2010) for cold, foreground clouds on the line of sight towards G10.6-0.4., 5 pages, 3 figures, paper to be published in the Herschel special issue of A&A letters
Published: 2010
Full Text: View/download PDF

26. Herschel/HIFI measurements of the ortho/para ratio in water towards Sagittarius B2(M) and W31C

Author: Benjamin Godard, Jonas Zmuidzinas, T. A. Bell, John H. Black, Frank Maiwald, Martin Emprechtinger, Maryvonne Gerin, C. Joblin, S. Wang, M. Perault, Patrick Hennebelle, Gary J. Melnick, Shanshan Yu, Peter Schilke, S. D. Lord, Paule Sonnentrucker, P. Hily-Blant, D. Johnstone, F. Boulanger, M. R. Schmidt, D. Teyssier, Raquel Monje, Alexandre Karpov, Jacob Kooi, Stephan Schlemmer, M. Salez, Peter G. Martin, David A. Neufeld, P. F. Goldsmith, Neil Trappe, M. De Luca, Karl M. Menten, Robert Kołos, F. F. S. van der Tak, Javier R. Goicoechea, Emmanuel Caux, Sébastien Maret, S.-L. Qin, Thomas R. Geballe, Cecile Gry, Neal R. Erickson, Rene Plume, Harold W. Yorke, Jesús Martín-Pintado, E. Falgarone, J. A. Murphy, Sylvie Cabrit, M. Kaźmierczak, Nathan R. Crockett, Eric Herbst, Jacek Krełowski, Charlotte Vastel, José Cernicharo, Holger S. P. Müller, P. Zaal, John C. Pearson, Carina M. Persson, Patrick W. Morris, Marie-Lise Dubernet, H. Gupta, P. J. Encrenaz, Rudolf Schieder, Fabien Daniel, Audrey Coutens, Adwin Boogert, Geoffrey A. Blake, Cecilia Ceccarelli, Edwin A. Bergin, J. Stutzki, Dariusz C. Lis, Thomas F. Giesen, Emmanuel Dartois, Bhaswati Mookerjea, Thomas G. Phillips, Laurent Pagani, Volker Ossenkopf, C. Comito, Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Astronomy, and Faure, Alexandre
Subjects: Experimental Physics, FOS: Physical sciences, Astrophysics, 01 natural sciences, ISM: abundances, COLOGNE DATABASE, OXYGEN, 0103 physical sciences, ABSORPTION, Sagittarius B2, 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Physics, AMMONIA, CDMS, Line-of-sight, SPECTROSCOPY, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], astrochemistry, ASTRONOMY, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, ISM: molecules, molecular processes, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), MOLECULAR CLOUDS, VAPOR, submillimeter: ISM, SUBMILLIMETER
Abstract: We present Herschel/HIFI observations of the fundamental rotational transitions of ortho- and para-H$_2^{16}$O and H$_2^{18}$O in absorption towards Sagittarius~B2(M) and W31C. The ortho/para ratio in water in the foreground clouds on the line of sight towards these bright continuum sources is generally consistent with the statistical high-temperature ratio of 3, within the observational uncertainties. However, somewhat unexpectedly, we derive a low ortho/para ratio of $2.35 \pm 0.35$, corresponding to a spin temperature of $\sim$27~K, towards Sagittarius~B2(M) at velocities of the expanding molecular ring. Water molecules in this region appear to have formed with, or relaxed to, an ortho/para ratio close to the value corresponding to the local temperature of the gas and dust., Accepted for publication in A&A, HIFI Special Issue; 5 pages, 3 figures
Published: 2010
Full Text: View/download PDF

27. The Herschel-Heterodyne Instrument for the Far-Infrared (HIFI)

Author: Brian Jackson, B. Kopf, R. Bieber, R. Güsten, A. M. di Giorgio, J. A. Stern, Holger S. P. Müller, B. J. van Leeuwen, G. S. Liu, R. Orfei, Neal R. Erickson, R. Lai, B. Delforges, Wolfgang Wild, Christian Leinz, O. Coeur-Joly, J. Desbat, David Teyssier, S. D. Lord, Karl Jacobs, Bruce Bumble, Lorene Samoska, M. Rataj, R. H. Lin, Dominicus Kester, M. Salez, X. Tielens, Alexandre Karpov, Paolo Saraceno, K. Edwards, R. Huisman, A. Megej, K. F. Schuster, Michel Fich, L. Dubbeldam, Serguei Cherednichenko, H. Golstein, Christian Monstein, J. A. Murphy, C. van Baaren, Victor Belitsky, P. Planesas, E. Natale, Michael Olberg, Lorenzo Piazzo, T. Peacock, Martin Eggens, Emmanuel Caux, W. A. Hatch, Neil Trappe, Hubregt J. Visser, Herbert Zirath, Jaap Evers, S. Phillip-May, Alain Maestrini, Hamid Javadi, Jacob Kooi, Th. de Graauw, F. Schmülling, E. C. Honingh, C. McCoey, J. C. Pearson, W. Luinge, I. Lopez-Fernandez, W. M. Laauwen, M. Michalska, Bengt Larsson, S. Wulff, John Gill, René Liseau, Volker Ossenkopf, Colin Borys, B. Kruizenga, Rafael Teipen, C. Kramer, A. Cros, H. Goulooze, P. Cais, W. Nowosielski, Goutam Chattopadhyay, M. Stokroos, Rafael Bachiller, F. Zwart, C. Gal, Piotr Orleanski, J. Kawamura, H. Smit, O. Siebertz, H. Aarts, Francesco Nuzzolo, L. Meinsma, Jonas Zmuidzinas, R. Assendorp, D. A. Beintema, H. van de Stadt, Jesús Martín-Pintado, G. de Lange, Ryszard Szczerba, Erich Schlecht, R. Higgins, Christophe Risacher, Patrick W. Morris, H. Jacobs, Christopher Jarchow, Willem Jellema, Pieter Dieleman, Todd Gaier, B. Franke, J. Stutzki, Imran Mehdi, Th. Klein, Harald Franz Arno Merkel, T. Finn, M. Justen, P.R. Wesselius, M. Ciechanowicz, T. M. Klapwijk, Hans-Joachim Wunsch, C. Comito, P. Zaal, Erik L. Kollberg, C. Diez-Gonzalez, T. den Boggende, John Ward, Jian-Rong Gao, Pasquale Cerulli-Irelli, C. Kasemann, T. Kuhn, Frank Helmich, K. Wildeman, Henry G. LeDuc, L. Ravera, Frank Maiwald, Y. Delorme, D. Moratschke, F. Schlöder, J. M. Krieg, M. Olbrich, A. Marston, Juan Daniel Gallego, P.-P. Kooiman, E. Steinmetz, T. Gunsing, A. Naber, M. Melchior, Geert Keizer, M. Schultz, I. Peron, S. Gauffre, C. K. Wafelbakker, N. Whyborn, M. Krause, T. Tils, Alexander Loose, A. de Jonge, Pieter R. Roelfsema, Rudolf Schieder, M. Caris, S. Glenz, A. Barcia, W. Baechtold, Paul Hartogh, R. Shipman, Adwin Boogert, Arnold O. Benz, Thomas G. Phillips, California Institute of Technology (CALTECH), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Université Sciences et Technologies - Bordeaux 1, Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Department of Microtechnology and Nanoscience (MC2), Chalmers University of Technology [Gothenburg, Sweden], Laboratoire de Cosmologie, Astrophysique Stellaire & Solaire, de Planétologie et de Mécanique des Fluides (CASSIOPEE), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Dept Pathol & Microbiol, Université de Montréal (UdeM)-Faculté de médecine vétérinaire, Leibniz Institute for Crystal Growth, Leibniz Institute, Technische Universität Darmstadt (TU Darmstadt), Instituto de RadioAstronomía Milimétrica (IRAM), Centre National de la Recherche Scientifique (CNRS), Institut für Festkörpertheorie, Westfälische Wilhelms-Universität Münster (WWU), Institute of Molecular Medicine and Cell Research (ZBMZ), University of Freiburg [Freiburg], Onsala Space Observatory, Chalmers University of Technology [Göteborg], ESO, European Southern Observatory (ESO), Istituto di Fisica dello Spazio Interplanetario (IFSI), Consiglio Nazionale delle Ricerche (CNR), Max Planck Institute for Meteorology (MPI-M), Institut für Chemie und Dynamik der Geosphäre - Troposphäre (ICG-2), Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association-Helmholtz-Gemeinschaft = Helmholtz Association, Herschel Science Center [Madrid], European Space Astronomy Centre (ESAC), European Space Agency (ESA)-European Space Agency (ESA), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), École normale supérieure - Paris (ENS-PSL), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Technische Universität Darmstadt - Technical University of Darmstadt (TU Darmstadt), Westfälische Wilhelms-Universität Münster = University of Münster (WWU), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA), TNO Industrie en Techniek, and Astronomy
Subjects: Experimental Physics, Local oscillator, Observatories, Orbits, general [Submillimeter], 01 natural sciences, 7. Clean energy, spectroscopic [Techniques], law.invention, Far infrared, Spectrographs, law, spectrographs [Instrumentation], 010303 astronomy & astrophysics, instrumentation: spectrographs, Physics, Spectrometers, submillimeter: general, Bolometers, Correlators, methods: observational, infrared: general, Heterodyne, Frequency band, Submillimeter: generals, Instantaneous phase, Radio spectrum, Optics, Mixers (machinery), 0103 physical sciences, Frequency bands, observational [Methods], 010306 general physics, Remote sensing, techniques: spectroscopic, Spectrometer, business.industry, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Bolometer, generals [Submillimeter], Astronomy and Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Launching, general [Infrared], Space and Planetary Science, Heterodyning, Instruments, business
Abstract: International audience; Aims: This paper describes the Heterodyne Instrument for the Far-Infrared (HIFI) that was launched onboard ESA's Herschel Space Observatory in May 2009. Methods: The instrument is a set of 7 heterodyne receivers that are electronically tuneable, covering 480-1250 GHz with SIS mixers and the 1410-1910 GHz range with hot electron bolometer (HEB) mixers. The local oscillator (LO) subsystem comprises a Ka-band synthesizer followed by 14 chains of frequency multipliers and 2 chains for each frequency band. A pair of auto-correlators and a pair of acousto-optical spectrometers process the two IF signals from the dual-polarization, single-pixel front-ends to provide instantaneous frequency coverage of 2 × 4 GHz, with a set of resolutions (125 kHz to 1 MHz) that are better than 0.1 km s-1. Results: After a successful qualification and a pre-launch TB/TV test program, the flight instrument is now in-orbit and completed successfully the commissioning and performance verification phase. The in-orbit performance of the receivers matches the pre-launch sensitivities. We also report on the in-orbit performance of the receivers and some first results of HIFI's operations. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.
Published: 2010
Full Text: View/download PDF

28. Herschel observations of EXtra-Ordinary Sources (HEXOS): detecting spiral arm clouds by CH absorption lines

Author: R. Bachille, T. A. Bell, H. Gupta, A. C. A. Boogert, H. W. Yorke, Martin Emprechtinger, Nathan R. Crockett, Cecilia Ceccarelli, P. J. Encrenaz, M. Perault, José Cernicharo, Laurent Pagani, Volker Ossenkopf, Eric Herbst, R. Rolffs, D. C. Lis, Pierrick Martin, Thomas F. Giesen, Emmanuel Caux, C. Joblin, E. Falgarone, Karl M. Menten, D. Johnstone, S.-L. Qin, T. Möller, Gary J. Melnick, Peter Schilke, J. R. Goicoechea, Michael Olberg, M. Salez, Sébastien Maret, Rene Plume, Jacob Kooi, Stephan Schlemmer, Patrick W. Morris, Jesús Martín-Pintado, Thomas G. Phillips, J. C. Pearson, W. Baechtold, Arnaud Belloche, Goutam Chattopadhyay, S. D. Lord, Alexandre Karpov, N. Honingh, Charlotte Vastel, C. Comito, E. A. Bergin, Neil Trappe, J. L. Gill, J. Stutzki, J.-M. Krieg, Fabien Daniel, L. H. Nordh, Jonas Zmuidzinas, S. Cabrit, M. C. Diez-Gonzalez, Maryvonne Gerin, Rudolf Schieder, F. F. S. van der Tak, Paul Hartogh, W. D. Langer, Marie-Lise Dubernet, S. Wang, G. A. Blake, Shanshan Yu, R. Güsten, Holger S. P. Müller, David A. Neufeld, P. F. Goldsmith, J. A. Murphy, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), I. Physikalisches Institut [Köln], Universität zu Köln, Max Planck Institute for Radio Astronomy, Hamburger Synchrotronstrahlungslabor HASYLAB at Deutsches Elektronen Synchrotron DESY (HASYLAB), Deutsches Elektronen-Synchrotron [Hamburg] (DESY), Université de Cologne, Institut de Physique 1, Université de Cologne, Max-Planck-Institut für Radioastronomie (MPIFR), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), California Institute of Technology (CALTECH), Department of Astronomy [Ann Arbor], University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Laboratoire Optimisation de la Conception et Ingénierie de l'Environnement (LOCIE), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Univ Toulouse UPS, Ctr Etud Spatiale Rayonnements, F-31062 Toulouse 9, France, Centre Etud Spatiale Rayonnements Toulouse, CNRS INSU, UMR 5187, F-31028 Toulouse 4, France, UMR 5187 Toulouse, Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Université Paris sciences et lettres (PSL), Cahill Center for Astronomy and Astrophysics, Laboratoire de Radioastronomie (LRA), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Ohio State Univ, Dept Phys, Columbus, OH 43210 USA, Ohio State University [Columbus] (OSU), Ohio State Univ, Dept Astron & Chem, Columbus, OH 43210 USA, Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC V9E 2E7 Canada, Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, Laboratoire de Modélisation Multi-échelles des Combustibles (LM2C), Service d'Etudes de Simulation du Comportement du combustibles (SESC), Département d'Etudes des Combustibles (DEC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Département d'Etudes des Combustibles (DEC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, CALTECH, Ctr Infrared Proc & Anal, Pasadena, CA 91125 USA, CALTECH, Ctr Infrared Proc & Anal, Pasadena, Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), SRON Netherlands Institute for Space Research (SRON), foreign laboratories (FL), CERN [Genève], Department of Physics and Astronomy [Calgary], University of Calgary, Laboratoire de Didactique André Revuz (LDAR (EA_4434)), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université Paris Diderot - Paris 7 (UPD7)-Université d'Artois (UA), Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, A.M.Obukhov Institute of Atmospheric Physics (IAP), Russian Academy of Sciences [Moscow] (RAS), Millimeter-Wave Electronics Laboratory [ETH Zürich] (MWE), Department of Information Technology and Electrical Engineering [Zürich] (D-ITET), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Onsala Space Observatory, Chalmers University of Technology [Göteborg], Faure, Alexandre, Universität zu Köln = University of Cologne, École normale supérieure - Paris (ENS-PSL), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Harvard University-Smithsonian Institution, Infrared Processing and Analysis Center (IPAC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université d'Artois (UA)-Université Paris Diderot - Paris 7 (UPD7)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Univ Cologne, Inst Phys 1, D-50937 Cologne, Germany, Univ Cologne, Inst Phys 1, École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP), Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid 28850, Spain, Ctr Astrobiol CSIC INTA, Lab Astrofis Mol, Madrid, Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), California Institute of Technology (CALTECH)-NASA, CEA-Direction de l'Energie Nucléaire (CEA-DEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CEA-Direction de l'Energie Nucléaire (CEA-DEN), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), and Astronomy
Subjects: Physics, Spiral galaxy, 010504 meteorology & atmospheric sciences, Absorption spectroscopy, Experimental Physics, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, 01 natural sciences, Line width, Astrophysics - Astrophysics of Galaxies, Galaxy, ISM: abundances, ISM: molecules, Linear relationship, [PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), 0103 physical sciences, [SDU.ASTR.GA]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA], Spectral resolution, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract: We have observed CH absorption lines ($J=3/2, N=1 \leftarrow J=1/2, N=1$) against the continuum source Sgr~B2(M) using the \textit{Herschel}/HIFI instrument. With the high spectral resolution and wide velocity coverage provided by HIFI, 31 CH absorption features with different radial velocities and line widths are detected and identified. The narrower line width and lower column density clouds show `spiral arm' cloud characteristics, while the absorption component with the broadest line width and highest column density corresponds to the gas from the Sgr~B2 envelope. The observations show that each `spiral arm' harbors multiple velocity components, indicating that the clouds are not uniform and that they have internal structure. This line-of-sight through almost the entire Galaxy offers unique possibilities to study the basic chemistry of simple molecules in diffuse clouds, as a variety of different cloud classes are sampled simultaneously. We find that the linear relationship between CH and H$_2$ column densities found at lower $A_V$ by UV observations does not continue into the range of higher visual extinction. There, the curve flattens, which probably means that CH is depleted in the denser cores of these clouds., Comment: Accepted for publication in A&A, HIFI Special Issue
Published: 2010
Full Text: View/download PDF

29. Development of Low Noise THz SIS Mixer Using an Array of Nb/Al-AlN/NbTiN Junctions

Author: David P. Miller, J. A. Stern, Alexandre Karpov, Henry G. LeDuc, B. Bumble, and Jonas Zmuidzinas
Subjects: Physics, business.industry, Stratospheric Observatory for Infrared Astronomy, Terahertz radiation, Circuit design, Slot antenna, Condensed Matter Physics, Submillimetre astronomy, Electronic, Optical and Magnetic Materials, law.invention, law, Optoelectronics, Electrical and Electronic Engineering, business, Frequency mixer, Noise (radio), Beam splitter
Abstract: We report the development of a low noise and broadband SIS mixer aimed for 1 THz channel of the Caltech Airborne Submillimeter Interstellar Medium Investigations Receiver (CASIMIR), designed for the Stratospheric Observatory for Infrared Astronomy, (SOFIA). The mixer uses an array of two 0.24 mum^2 Nb/Al-AlN/NbTiN SIS junctions with the critical current density of 30-50 kA/cm^2 . An on-chip double slot planar antenna couples the mixer circuit with the telescope beam. The mixer matching circuit is made with Nb and gold films. The mixer IF circuit is designed to cover 4-8 GHz band. A test receiver with the new mixer has a low noise operation in 0.87-1.12 THz band. The minimum receiver noise measured in our experiment is 353 K (Y = 1.50). The receiver noise corrected for the loss in the LO injection beam splitter is 250 K. The combination of a broad operation band of about 250 GHz with a low receiver noise makes the new mixer a useful element for application at SOFIA.
Published: 2009

30. CASIMIR: The Caltech Airborne Submillimeter Interstellar Medium Investigations Receiver

Author: Michael L. Edgar, F. Rice, Alexandre Karpov, Andrew I. Harris, Sean Lin, Jonas Zmuidzinas, David P. Miller, and Simon J. E. Radford
Subjects: Interstellar medium, Physics, Casimir effect, Far infrared, Spectrometer, Terahertz radiation, Stratospheric Observatory for Infrared Astronomy, Astronomy, Astrophysics, Heterodyne detection, Submillimetre astronomy
Abstract: CASIMIR, the Caltech Airborne Submillimeter Interstellar Medium Investigations Receiver, is a far infrared and submillimeter heterodyne spectrometer under development for the Stratospheric Observatory For Infrared Astronomy, SOFIA. CASIMIR will carry out observations in the frequency range from 500 GHz up to 1.4 THz, with extremely high spectral resolution, of order 106. Capitalizing on recent advances in SIS mixer development, CASIMIR will cover this region of the spectrum with unprecedented sensitivity. CASIMIR is extremely well suited to observe the warm, ~100 K, interstellar medium, particularly water lines, in both Galactic and extragalactic sources.
Published: 2008
Full Text: View/download PDF

31. CASIMIR, The Caltech airborne submillimeter interstellar medium investigations receiver

Author: David P. Miller, Jonas Zmuidzinas, Sean Lin, Alexandre Karpov, Simon J. E. Radford, Michael L. Edgar, Duncan, William D., Holland, Wayne S., Withington, Stafford, and Zmuidzinas, Jonas
Subjects: Interstellar medium, Physics, Heterodyne, Casimir effect, Far infrared, Spectrometer, Galactic astronomy, Molecular cloud, Astronomy, Astrophysics, Galaxy
Abstract: CASIMIR, the Caltech Airborne Submillimeter Interstellar Medium Investigations Receiver is a multiband, far infrared and submillimeter, high resolution, heterodyne spectrometer under development for SOFIA. It is a first generation, PI class instrument. CASIMIR is designed for detailed, high sensitivity observations of warm (100 K) interstellar gas both in external galaxies and Galactic sources, including molecular clouds, circumstellar envelopes, and protostellar cores. Combining the 2.5 m SOFIA mirror with state of the art superconducting mixers, will give CASIMIR unprecedented sensitivity. Initially, CASIMIR will have two bands, at 1000 and 1250 GHz, and a further three bands, 550, 750, 1400 GHz, will be added soon after. Any four bands will be available on each flight. The availability of multiple bands during each flight will allow for efficient use of flight time. For example, searches for weak lines from rare species in bright sources can be carried out on the same flight with observations of abundant species in faint or distant objects.
Published: 2008
Full Text: View/download PDF

32. Low Noise 1 THz–1.4 THz Mixers Using Nb/Al-AlN/NbTiN SIS Junctions

Author: Alexandre Karpov, Jonas Zmuidzinas, F. Rice, J. A. Stern, David Miller, Henry G. LeDuc, and B. Bumble
Subjects: Cryostat, Heterodyne, Physics, Noise temperature, business.industry, Terahertz radiation, Stratospheric Observatory for Infrared Astronomy, Niobium, chemistry.chemical_element, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, chemistry, Low-power electronics, Optoelectronics, Electrical and Electronic Engineering, business, Noise (radio), Caltech Library Services
Abstract: We present the development of a low noise 1.2 THz and 1.4 THz SIS mixers for heterodyne spectrometry on the Stratospheric Observatory For Infrared Astronomy (SOFIA) and Herschel Space Observatory. This frequency range is above the limit for the commonly used Nb quasi particle SIS junctions, and a special type of hybrid Nb/AlN/NbTiN junctions has been developed for this project.We are using a quasi-optical mixer design with two Nb/AlN/NbTiN junctions with an area of 0.25 µm^2. The SIS junction tuning circuit is made of Nb and gold wire layers. At 1.13 THz the minimum SIS receiver uncorrected noise temperature is 450 K. The SIS receiver noise corrected for the loss in the LO coupler and in the cryostat optics is 350–450 K across 1.1–1.25 THz band. The receiver has a uniform sensitivity in a full 4–8 GHz IF band. The 1.4 THz SIS receiver test at 1.33–1.35 THz gives promising results, although limited by the level of available LO power. Extrapolation of the data obtained with low LO power level shows a possibility to reach 500 K DSB receiver noise using already existing SIS mixer.
Published: 2007

33. Electrodynamics of planar Archimedean spiral resonator

Author: A. S. Averkin, Alexey V. Ustinov, Alexandre Karpov, Nataliya Maleeva, N. N. Abramov, Mikhail V. Fistul, and Alexander P. Zhuravel
Subjects: Superconductivity, Physics, Resonator, Planar, Quantum electrodynamics, Numerical analysis, Excited state, General Physics and Astronomy, Radius, Boundary value problem, Spiral
Abstract: We present a theoretical and experimental study of electrodynamics of a planar spiral superconducting resonator of a finite length. The resonator is made in the form of a monofilar Archimedean spiral. By making use of a general model of inhomogeneous alternating current flowing along the resonator and specific boundary conditions on the surface of the strip, we obtain analytically the frequencies fn of resonances which can be excited in such system. We also calculate corresponding inhomogeneous RF current distributions ψ n ( r ) , where r is the coordinate across a spiral. We show that the resonant frequencies and current distributions are well described by simple relationships f n = f 1 n and ψ n ( r ) ≃ sin [ π n ( r / R e ) 2 ] , where n = 1 , 2... and Re is the external radius of the spiral. Our analysis of electrodynamic properties of spiral resonators' is in good agreement with direct numerical simulations and measurements made using specifically designed magnetic probe and laser scanning microscope.
Published: 2015
Full Text: View/download PDF

34. Development of 1.25 THz SIS mixer for Herschel Space Observatory

Author: J. A. Stern, Bruce Bumble, Jonas Zmuidzinas, F. Rice, Alexandre Karpov, Henry G. LeDuc, David P. Miller, Zmuidzinas, Jonas, Holland, Wayne S., Withington, Stafford, and Duncan, William D.
Subjects: Physics, Heterodyne, Noise temperature, Optics, Far infrared, Terahertz radiation, business.industry, Double-sideband suppressed-carrier transmission, Y-factor, Center frequency, business, Telecommunications, Noise (radio)
Abstract: We summarize the development and the delivery of two SIS mixers for the 1.1-1.25 THz band of the heterodyne spectrometer of Herschel Observatory (HSO). The quasi-op tical SIS mixer has two Nb/Al N/NbTiN junctions with the area of 0.25 um 2 . The Josephson critical current density in the junction is 30-50 kA/cm . The tuning circuit integrated with SIS junc tion has the base electrode of Nb and a gold wire layer. With the new SIS mixers the test receiver maximum Y factor is 1.41. The minimum receiver uncorrected DSB noise temperature is 450 K. The SIS receiver noise corrected for the loss in the optics is 350-450 K across the 1100-1250 GHz band. The receiver has a uniform sensitivity in the full IF range of 4-8 GHz. The sub-micron sized SIS junction shape is optimized to ease the suppression of the Josephson current, and the receiver operation is stable. The measured mixer beam pattern is symmetrical and, in a good agreement with the requirements, has the f/d =4.25 at the central frequency of the operation band. The minimum DSB SIS receiver noise is close to 6 hv/k, the lowest value achieved thus far in the THz frequencies range. Keywords: SIS mixer, THz frequency, far infrared, low noise, Herschel space observatory, radio astronomy.
Published: 2006

35. Low-noise SIS mixer for far-infrared radio astronomy

Author: Alexandre Karpov, Jeffrey A. Stern, Jonas Zmuidzinas, Bruce Bumble, David P. Miller, Henry G. LeDuc, F. Rice, Zmuidzinas, Jonas, Holland, Wayne S., and Withington, Stafford
Subjects: Physics, Heterodyne, Optics, Far infrared, Sideband, Terahertz radiation, business.industry, Transmission line, Local oscillator, business, Frequency mixer, Noise (radio)
Abstract: We present a low noise SIS mixer developed for the 1.2 THz band of the heterodyne spectrometer of the Herschel Space Observatory. With the launch of the Herschel SO in 2007, this device will be among the first SIS mixers flown in space. This SIS mixer has a quasi-optical design, with a double slot planar antenna and an extended spherical lens made of pure Si. The SIS junctions are Nb/AlN/NbTiN with a critical current density of about 30 KA/cm2 and with the junction area of a quarter of a micron square. Our mixer circuit uses two SIS junctions biased in parallel. To improve the simultaneous suppression of the Josephson current in each of them, we use diamond-shaped junctions. A low loss Nb/Au micro-strip transmission line is used for the first time in the mixer circuit well above the gap frequency of Nb. The minimum uncorrected Double Sideband receiver noise is 550 K (Y=1.34). The minimum receiver noise corrected for the local oscillator beam splitter and for the cryostat window is 340 K, about 6 hv/k, the lowest value achieved thus far in the THz frequencies range.
Published: 2004
Full Text: View/download PDF

36. THz instrumentation for the Herschel Space Observatory's heterodyne instrument for far infrared

Author: W. A. Hatch, Imran Mehdi, Frank Maiwald, Michael Paquette, John C. Pearson, Robert Lin, Lorene Samoska, David P. Miller, Robert Ferber, Mary Wells, K. T. Liao, Thomas G. Phillips, Sander Weinreb, James Velebir, J. Kawamura, Alain Maestrini, William Chun, John Gill, Alexandre Karpov, Alejandro Peralta, John Ward, Hamid Javadi, Bradley P. Finamore, Jeffrey A. Stern, Neal R. Erickson, Robert J. Dengler, Henry G. LeDuc, Bruce Bumble, David Pukala, Todd Gaier, Gerald Swift, Edward M. Luong, Raymond Tsang, Jonas Zmuidzinas, Erich Schlecht, Zmuidzinas, Jonas, Holland, Wayne S., and Withington, Stafford
Subjects: Heterodyne, Physics, Optics, Intermediate frequency, Far infrared, Terahertz radiation, business.industry, Amplifier, Local oscillator, High-electron-mobility transistor, Telecommunications, business, Varicap
Abstract: The Heterodyne Instrument for Far Infrared (HIFI) on ESA's Herschel Space Observatory utilizes a variety of novel RF components in its five SIS receiver channels covering 480-1250 GHz and two HEB receiver channels covering 1410-1910 GHz. The local oscillator unit will be passively cooled while the focal plane unit is cooled by superfluid helium and cold helium vapors. HIFI employs W-band GaAs amplifiers, InP HEMT low noise IF amplifiers, fixed tuned broadband planar diode multipliers, high power W-bapd Isolators, and novel material systems in the SIS mixers. The National Aeronautics and Space Administration through the Jet Propulsion Laboratory is managing the development of the highest frequency (1119-1250 GHz) SIS mixers, the local oscillators oscillators for the three highest frequency receivers as well as W-band power amplifiers, high power W-band isolators, varactor diode devices for all high frequency multipliers and InP HEMT components for all the receiver channels intermediate frequency amplifiers. The NASA developed components represent a significant advancement in the available performance. This paper presents an update of the performance and the current state of development.
Published: 2004
Full Text: View/download PDF

37. The Influence of fold and fracture development on reservoir behavior of the Lisburne Group of northern Alaska

Author: Thomas M. Parris, Wesley K. Wallace, Ryan Shackleton, Margarete A. Jadamec, Michelle M. McGee, John C. Lorenz, Joseph Brinton, Jerry Jensen: Michael T. Whalen, Catherine L. Hanks, Alexandre Karpov, P. K. Atkinson, and Thang Bui
Subjects: Paleontology, Shear (geology), Lithology, Anticline, Lithostratigraphy, Carbonate rock, Thrust fault, Fold (geology), Syncline, Geomorphology, Geology
Abstract: The Carboniferous Lisburne Group is a major carbonate reservoir unit in northern Alaska. The Lisburne is folded and thrust faulted where it is exposed throughout the Brooks Range, but is relatively undeformed in areas of current production in the subsurface of the North Slope. The objectives of this study were to develop a better understanding of four major aspects of the Lisburne: (1) The geometry and kinematics of folds and their truncation by thrust faults. (2) The influence of folding on fracture patterns. (3) The influence of deformation on fluid flow. (4) Lithostratigraphy and its influence on folding, faulting, fracturing, and reservoir characteristics. Symmetrical detachment folds characterize the Lisburne in the northeastern Brooks Range. In contrast, Lisburne in the main axis of the Brooks Range is deformed into imbricate thrust sheets with asymmetrical hangingwall anticlines and footwall synclines. The Continental Divide thrust front separates these different structural styles in the Lisburne and also marks the southern boundary of the northeastern Brooks Range. Field studies were conducted for this project during 1999 to 2001 in various locations in the northeastern Brooks Range and in the vicinity of Porcupine Lake, immediately south of the Continental Divide thrust front. Results are summarized below for the four main subject areas of the study.
Published: 2004
Full Text: View/download PDF

38. Terahertz frequency receiver instrumentation for Herschel's heterodyne instrument for far infrared (HIFI)

Author: John Gill, Alexandre Karpov, Huei Wang, Lorene Samoska, Jonas Zmuidzinas, Erich Schlecht, Neal R. Erickson, David P. Miller, Dennis G. Harding, Frank Maiwald, J. A. Stern, Imran Mehdi, Dave Pukala, W. A. Hatch, Yun Chung, Bruce Bumble, Todd Gaier, William R. McGrath, Robert Ferber, John Ward, J. Kawamura, Richard Lai, S.C. Martin, Alain Maestrini, John C. Pearson, Jerry Swift, Thomas G. Phillips, Henry G. LeDuc, and Mather, John C.
Subjects: Heterodyne, Optical amplifier, Physics, Optics, Far infrared, Intermediate frequency, Terahertz radiation, business.industry, Amplifier, Local oscillator, business, Varicap
Abstract: The Heterodyne Instrument for Far Infrared (HIFI) on ESA's Herschel Space Observatory is comprised of five SIS receiver channels covering 480-1250 GHz and two HEB receiver channels covering 1410-1910 GHz. Two fixed tuned local oscillator sub-bands are derived from a common synthesizer to provide the front-end frequency coverage for each channel. The local oscillator unti will be passively cooled while the focal plane unit is cooled by superfluid helium and cold helium vapors. HIFI employs W-band GaAs amplifiers, InP HEMT low noise IF amplifiers, fixed tuned broadband planar diode multipliers, and novel material systems in the SIS mixtures. The National Aeronautics and Space Administration's Jet Propulsion Laboratory is managing the development of the highest frequency (1119-1250 GHz) SIS mixers, the highest frequency (1650-1910 GHz) HEB mixers, local oscillators for the three highest frequency receivers as well as W-band power amplifiers, varactor diode devices for all high frequency multipliers and InP HEMT components for all the receiver channels intermediate frequency amplifiers. The NASA developed components represent a significant advancement in the available performance. The current state of the art for each of these devices is presented along with a programmatic view of the development effort.
Published: 2003

39. Low noise direct detector at submillimeter wavelength using SIS junction [Nb/AlO/sub x//Nb]

Author: J. Blondel, Alexandre Karpov, M. Voss, and K. H. Gundlach
Subjects: Physics, business.industry, Quantum limit, Bandwidth (signal processing), Bolometer, Detector, Niobium, chemistry.chemical_element, law.invention, Wavelength, Responsivity, chemistry, law, Optoelectronics, business, Type-II superconductor
Abstract: We have demonstrated the feasibility of a broad band SIS direct detector with a bandwidth up to 70 GHz around 330 GHz. The SIS detector responsivity approaches the quantum limit. The optical noise of 13 mK/spl radic/s measured with the new direct detector receiver is close to the noise of bolometer receiver developed for radioastronomy at the same wavelength. The SIS direct detector works at 4.5 K instead of 0.1-0.3 K required for bolometer receiver.
Published: 2002
Full Text: View/download PDF

40. The Influence of Fold and Fracture Development on Reservoir Behavior of the Lisburne Group of Northern Alaska

Author: Wesley K. Wallace, Michael T. Whalen, Catherine L. Hanks, Jerry L. Jensen, Margarete A. Jadamec, J. Ryan Shackleton, Michelle M. McGee, and Alexandre Karpov
Subjects: Shear (geology), Lithology, Carboniferous, Anticline, Lithostratigraphy, Carbonate rock, Thrust fault, Fold (geology), Petrology, human activities, Geology
Abstract: The Carboniferous Lisburne Group is a major carbonate reservoir unit in northern Alaska. The lisburne is detachment folded where it is exposed throughout the northeastern Brooks Range, but is relatively underformed in areas of current production in the subsurface of the North Slope. The objectives of this study are to develop a better understanding of four major aspects of the Lisburne: (1) The geometry and kinematics of detachment folds and their truncation by thrust faults, (2) The influence of folding on fracture patterns, (3) The influence of deformation on fluid flow, and (4) Lithostratigraphy and its influence on folding, faulting, fracturing, and reservoir characteristics.
Published: 2001
Full Text: View/download PDF

41. EMCOR radiometer: calibration and first tests

Author: Juan Daniel Gallego-Puyol, D. Maier, C. Viguerie, Brian N. Ellison, W. Amacher, U. Klein, A. Barcia, Niklaus A. Kaempfer, Alexandre Karpov, A. Raeisaenen, José Cernicharo, R. Siddans, J.T. Louhi, D. N. Matheson, M. Gustafsson, J. de La Noë, Juha Mallat, Philippe Ricaud, M. Wuethrich, Philippe Baron, Klaus Kuenzi, Gerard Beaudin, B. Franke, and Juan R. Pardo
Subjects: Geography, law, Instrumentation, Range (aeronautics), Superheterodyne receiver, Calibration, Radiometry, Superconducting tunnel junction, Signal, Stratosphere, Remote sensing, law.invention
Abstract: The objective of the European project EMCOR was the development of a heterodyne receiver for the frequency range of 201 to 210 GHz for the measurement of the amounts of various minor constituents of the stratosphere involved in ozone chemistry. In order to be able to measure even very faint spectral lines a superconducting tunnel junction has been chosen as mixer element. Additionally, special care has been taken in developing the calibration unit of the system. Besides the classical hot-cold calibration three different balancing methods can be employed: a beam-switch technique with an atmospheric reference signal, a beam switch technique with a reference signal from a variable reference load or a frequency switch technique. The system has been integrated and is currently under testing. It will be installed at the International Scientific Station Jungfraujoch in he Swiss Alps and operated within the framework of the European Alpine stations of the Network for the Detection of Stratospheric Change.
Published: 1998
Full Text: View/download PDF

42. Receivers for ground-based millimeter-wave radio telescopes

Author: Alexandre Karpov
Subjects: Physics, Noise temperature, Radio receiver design, business.industry, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Radio telescope, Optics, Extremely high frequency, Very-long-baseline interferometry, Astronomical interferometer, business, Noise (radio), Radio astronomy
Abstract: We present a study of requirements on the sensitivity of mm and sub millimeter wave receivers for application in radio astronomy. The study is based on the experience of the operation of the SIS receivers at the radio telescopes of IRAM and considers also the conditions of operation at the future radioastronomical instruments such as LSA, MMA and LSMA. Using a radio telescope and atmospheric model we consider the effect of the receiver sensitivity on the radio telescope operation in terms of observing time. The observing time at a radio telescope depends on the system noise temperature as strongly as on collecting area, which defines nearly all the cost of modern mm and sub mm instruments. As a compromise between the receiver development effort and the system performance we introduce a criterion of an 'optimum' receiver noise. A strict requirement on the receiver operation is obtained. For an efficient use of the existing and the future radio telescopes, a 10 - 20 K SSB receiver noise in the mm band and 20 - 40 K SSB at sub millimeter wavelength are necessary. Finally the status and the perspectives for SIS receiver development for mm and sum mm radio astronomy are presented.
Published: 1998
Full Text: View/download PDF

43. Electrodynamics of a ring-shaped spiral resonator

Author: Alexandre Karpov, Alexey V. Ustinov, Mikhail V. Fistul, Nataliya Maleeva, A. S. Averkin, P. Jung, and Alexander P. Zhuravel
Subjects: Electromagnetic field, Physics, Condensed Matter - Materials Science, Condensed Matter - Superconductivity, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, General Physics and Astronomy, Resonance, Metamaterial, Electromagnetic radiation, Magnetic field, Superconductivity (cond-mat.supr-con), Resonator, Quantum electrodynamics, Boundary value problem, Spiral
Abstract: We present analytical, numerical and experimental investigations of electromagnetic resonant modes of a compact monofilar Archimedean spiral resonator shaped in a ring, with no central part. Planar spiral resonators are interesting as components of metamaterials for their compact deep-subwavelength size. Such resonators couple primarily to the magnetic field component of the incident electromagnetic wave, offering properties suitable for magnetic meta-atoms. Surprisingly, the relative frequencies of the resonant modes follow the sequence of the odd numbers, despite the nearly identical boundary conditions for electromagnetic fields at the extremities of the resonator. In order to explain the observed spectrum of resonant modes, we show that the current distribution inside the spiral satisfies a particular Carleman type singular integral equation. By solving this equation, we obtain a set of resonant frequencies. The analytically calculated resonance frequencies and the current distributions are in good agreement with experimental data and the results of numerical simulations. By using low-temperature laser scanning microscopy of a superconducting spiral resonator, we compare the experimentally visualized ac current distributions over the spiral with the calculated ones. Theory and experiment agree well with each other. Our analytical model allows for calculation of a detailed three-dimensional magnetic field structure of the resonators., 25 pages, 8 figures
Published: 2014
Full Text: View/download PDF

44. Noise properties of a mixer with SIS NbN quasi-particle tunnel junctions

Author: Takada Susumu, K. H. Gundlach, Masahiro Aoyagi, B. Plathner, and Alexandre Karpov
Subjects: Physics, Noise temperature, business.industry, Frequency band, Local oscillator, Quantum limit, Electrical engineering, Niobium, chemistry.chemical_element, chemistry, Double-sideband suppressed-carrier transmission, Optoelectronics, business, Frequency mixer, Noise (radio)
Abstract: We present the noise properties of a mixer with the NbN-MgO-NbN quasiparticle tunnel junctions. Our work is based on experiment in the 120-180 GHz range with the NbN tunnel junctions in the mixer. Mixer printed circuit is totally made of NbN. The mixer operates at 5.4 K temperature unacceptable with Nb junctions. The minimum DSB receiver noise temperature is about 65 K at 162 GHz and approaches the Nb SIS mixer performance in mm band. It has been found that the noise sources in the NbN junctions are comparable to the Nb junctions and that the receiver noise with the NbN SIS mixer may be only few times more than the quantum limit of noise in the frequency range below the gap frequency. Output noise of the SIS mixer has been found constant in a wide frequency band and within an important range of the local oscillator amplitudes.
Published: 1995
Full Text: View/download PDF

45. Low nose submillimetre SIS receiver for 30 m IRAM radiotelescope

Author: Alexandre Karpov, B. Lazareff, J. Blondel, K. H. Gundlach, M. Voss, and M. Carter
Subjects: Physics, Noise temperature, business.industry, Electrical engineering, law.invention, Low noise, Telescope, Wavelength, Optics, law, Wide band, Radio frequency, Wideband, business, Waveguide
Abstract: A low noise SIS mixer receiver is prepared in IRAM for the operation at 0.8 mm wavelength on the 30 M telescope at Pico Veleta in Spain. For this receiver a new fixed-tuned waveguide SIS mixer is developed. This mixer is able to operate in a wide band being fixed tuned. The present mixer design uses relative large Nb\AIoxide\Nb SIS junctions (1-2 ?2) in which parallel inductive tuning is implemented with quasi-lumped elements. Experimental measurements agree with model predictions of the new SIS mixers performance. At the IRAM 30-m radiotelescope the best receiver DSB noise temperature achieved in the 0.8 mm band is about 70 K It is believed that it is the first wide band receiver with a fixed tuned submillimeter SIS mixer on the radiotelescope with the lowest noise temperature published for the moment.
Published: 1993
Full Text: View/download PDF

46. Herschelobservations of EXtra-Ordinary Sources (HEXOS): The Terahertz spectrum of Orion KL seen at high spectral resolution

Author: Thomas F. Giesen, S.-L. Qin, S. D. Lord, Alexandre Karpov, Rene Plume, Neil Trappe, Fabien Daniel, G. A. Blake, C. Joblin, Patrick W. Morris, R. Güsten, Emmanuel Caux, Peter Schilke, Rudolf Schieder, M. Perault, C. Comito, J. Stutzki, Bruce Bumble, José Cernicharo, E. A. Bergin, Stephan Schlemmer, P. J. Encrenaz, Frank Helmich, Marie-Lise Dubernet, Holger S. P. Müller, Shanshan Yu, E. Falgarone, W. D. Langer, W. D. Latter, S. Wang, Thomas G. Phillips, D. C. Lis, Pierrick Martin, S. Cabrit, David A. Neufeld, P. F. Goldsmith, H. W. Yorke, D. Johnstone, Gary J. Melnick, Karl M. Menten, Paul Hartogh, N. Honingh, Pieter R. Roelfsema, J.-M. Krieg, T. A. Bell, Volker Ossenkopf, H. Gupta, Sébastien Maret, J. Kawamura, Nathan R. Crockett, A. C. A. Boogert, Jacob Kooi, Martin Emprechtinger, Charlotte Vastel, Eric Herbst, Cecilia Ceccarelli, Aggm Tielens, J. R. Goicoechea, J. C. Pearson, J. A. Murphy, Jonas Zmuidzinas, F. F. S. van der Tak, Maryvonne Gerin, Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre d'étude spatiale des rayonnements (CESR), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Faure, Alexandre, and Astronomy
Subjects: Experimental Physics, 010504 meteorology & atmospheric sciences, Terahertz radiation, FOS: Physical sciences, Astrophysics, ISM: clouds, 7. Clean energy, 01 natural sciences, 0103 physical sciences, Emission spectrum, Spectral resolution, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, ISM: general, 0105 earth and related environmental sciences, Physics, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], astrochemistry, Spectrum (functional analysis), Astronomy and Astrophysics, ISM: molecules, Space observatory, On board, Astrophysics - Solar and Stellar Astrophysics, [SDU]Sciences of the Universe [physics], 13. Climate action, Space and Planetary Science, submillimeter: ISM
Abstract: We present the first high spectral resolution observations of Orion KL in the frequency ranges 1573.4 - 1702.8 GHz (band 6b) and 1788.4 - 1906.8 GHz (band 7b) obtained using the HIFI instrument on board the Herschel Space Observatory. We characterize the main emission lines found in the spectrum, which primarily arise from a range of components associated with Orion KL including the hot core, but also see widespread emission from components associated with molecular outflows traced by H2O, SO2, and OH. We find that the density of observed emission lines is significantly diminished in these bands compared to lower frequency Herschel/HIFI bands., Accepted for publication in the Herschel HIFI special issue of Astronomy and Astrophysics Letters, 5 pages, 3 figures
Published: 2010
Full Text: View/download PDF

47. 1.4 THz SIS mixer using Nb and Al tuning circuit

Author: Alexandre Karpov, Miller, D., Stern, J. A., Rice, F., Leduc, H. G., and Zmuidzinas, J.

48. Casimir: The caltech airborne fir/submm, high resolution heterodyne spectrometer

Author: Edgar, M. L., Harris, A. I., Hawkins, D. W., Alexandre Karpov, Miller, D., Rauch, K. P., and Zmuidzinas, J.

49. 350 GHz and 230 GHz mixers with the tuned SIS junctions

Author: Alexandre Karpov, Carter, M., Lazareff, B., Voss, M., Billon-Pierron, D., and Gundlach, K. H.

50. CASIMIR: A high resolution, far-IR/submm spectrometer for airborne astronomy

Author: Sean Lin, Frank Maiwald, Robert Lin, Simon J. E. Radford, Imran Mehdi, Alexandre Karpov, David P. Miller, John Ward, F. Rice, Michael L. Edgar, Martin Emprechtinger, Jonas Zmuidzinas, McLean, Ian S., Ramsay, Suzanne K., and Takami, Hideki
Subjects: Heterodyne, Physics, Infrared astronomy, Spectrometer, Terahertz radiation, business.industry, Stratospheric Observatory for Infrared Astronomy, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Radio spectrum, Optics, Observational astronomy, Far infrared, business, Astrophysics::Galaxy Astrophysics
Abstract: CASIMIR, the Caltech Airborne Submillimeter Interstellar Medium Investigations Receiver, is a far-infrared and submillimeter heterodyne spectrometer, being developed for the Stratospheric Observatory For Infrared Astronomy, SOFIA. CASIMIR will use newly developed superconducting-insulating-superconducting (SIS) mixers. Combined with the 2.5 m mirror of SOFIA, these detectors will allow observations with high sensitivity to be made in the frequency range from 500 GHz up to 1.4 THz. Initially, at least 5 frequency bands in this range are planned, each with a 4-8 GHz IF passband. Up to 4 frequency bands will be available on each flight and bands may be swapped readily between flights. The local oscillators for all bands are synthesized and tuner-less, using solid state multipliers. CASIMIR also uses a novel, commercial, field-programmable gate array (FPGA) based, fast Fourier transform spectrometer, with extremely high resolution, 22000 (268 kHz at 6 GHz), yielding a system resolution > 10 6 . CASIMIR is extremely well suited to observe the warm, ≈ 100K, interstellar medium, particularly hydrides and water lines, in both galactic and extragalactic sources. We present an overview of the instrument, its capabilities and systems. We also describe recent progress in development of the local oscillators and present our first astronomical observations obtained with the new type of spectrometer.

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Journal

Database

Publisher

59 results on '"Alexandre Karpov"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources