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With the upgrade from GRAVITY to GRAVITY$^+$ the instrument will evolve into an all-sky interferometer that can observe faint targets, such as high redshift AGN. Observing the faintest targets requires reducing the noise sources in GRAVITY as much as possible. The dominant noise source, especially in the blue part of the spectrum, is the backscattering of the metrology laser light onto the detector. To reduce this noise we introduce two new metrology modes. With a combination of small hardware changes and software adaptations, we can dim the metrology laser during the observation without losing the phase referencing. For single beam targets, we can even turn off the metrology laser for the maximum SNR on the detector. These changes lead to an SNR improvement of over a factor of two averaged over the whole spectrum and up to a factor of eight in the part of the spectrum currently dominated by laser noise., Comment: Proceeding of SPIE Astronomical Telescopes + Instrumentation 2022

The European Southern Observatory gives the opportunity to develop new third generation instruments for the Very Large Telescope Interferometer. Therefore, adaptive optics systems need to be upgraded, either for NAOMI on a 1.8-m auxiliary telescope or for MACAO on a 8-m unit telescope. It enables to access to new science cases such as active galactic nuclei with the GRAVITY+ project. We study here the requirements of such AO upgrade by increasing the number of sub-apertures of the wave-front sensor and the number of actuators of the deformable mirror. We evaluate the needs for a high-Strehl mode in the visible and near infrared wavelengths in various conditions of observation. We present numerical simulations to quantify the performance. We show that a moderate upgrade of NAOMI, and a significant upgrade of MACAO can enable both better dynamic range and sensitivity with the VLTI.

We present the successful demonstration of world's first large-separation ~30" off-axis fringe tracking with four telescopes in October 2019. With this technique we increase the sky-coverage for optical interferometry by orders of magnitude compared to current technology. Following the early work at the Palomar Testbed Interferometer, the first demonstration of off-axis fringe tracking at the Keck Interferometer and with PRIMA at the ESO Very Large Telescope Interferometer, and the breakthrough with the GRAVITY Galactic Center observations, we enhanced the VLTI infrastructure for GRAVITY to take advantage of the PRIMA Star separators and Differential Delay Lines for off-axis fringe tracking. In our presentation we give an introduction to the subject, present the enhancements of the VLTI, and present our results from the first on-sky operation in October 2019, with observations of the Orion Trapezium Cluster, a field brown dwarf, and a high redshift quasar.

The paper reports an overview of the preliminary optical design for the MICADO Relay Optics (RO) to enable early science observations of the instrument at the Extremely Large Telescope (ELT) with single-conjugate adaptive optics (SCAO). MICADO, the Multi-AO Imaging Camera for Deep Observations, is a first light imager, astrometric camera and spectrograph operating between 0.8 µm and 2.4 µm. The RO are based on a six mirror (6M) optical assembly that relays the telescope focal plane to an accessible position for the MICADO cryostat. The system includes three powered mirrors in a three-mirror-anastigmat configuration and three piston and tip- tilt flat mirrors for the alignment and the beam folding at the interfaces with the ELT and MICADO. This design represents an interesting example of optical performance optimization to achieve high performances optics both for the direct imaging channel and the pupil interface towards MICADO and the SCAO. The RO performances are analyzed and verified at a design level showing the compliance with the requirement specifications and the reliability of the design is assessed with an extended tolerance study and a minimization of the vignetting factor at the MICADO cold stop. The manuscript also contains a demonstration of the optical alignability of a 6M system in terms of pupil and focal plane steering that are essential to cope with the interface tolerances of the next generation of instrument at the foci of the extremely large telescopes.

MICADO, the Multi-AO-Imaging-Camera and Spectrometer for Deep Observations, is one of the first light instruments for the future 40 m class Extremely Large Telescope (ELT). MICADO utilizes the advanced laser guide star multiconjugate adaptive optics system MCAO developed by the MAORY consortium and the jointly developed singleconjugate adaptive optics system (SCAO). We present an overview on the conceptual design of the MICADO Cold Optical Instrument (COI) which comprises the infrared focal plane imager with its 3 x 3 4k2 HgCdTe detector array and a compact cross-dispersing slit spectrometer operating in the spectral range of 0.8 to 2.4 μm. High contrast imaging is enabled via a classical configuration of coronagraph and Lyot stops. The paper summarizes the MICADO COI interchangeable optics, its cryogenic implementation together with the modular opto-mechanical configuration of the cryo-mechanisms and the cryo-vacuum cooling system, which consists of a continuous LN2 flow cryostat.

MICADO is the European ELT first-light imager, working in the near-infrared at the telescope diffraction limit. Provided by MAORY, the ELT first-light adaptive optics module (AO), MCAO will be the primary AO mode of MICADO, driving the design of the instrument. MICADO will also come with a SCAO capability. Developed under MICADO’s responsibility and jointly by MICADO and MAORY, SCAO will be the first AO mode to be tested at the telescope, in a phased approach of the AO integration at the ELT. The MICADO-MAORY SCAO preliminary design review (PDR) will occur in November 2018. We present here different activities and results we have had in the past two years preparing this PDR, covering several fields (opto-mechanics, electronics, real-time and control software, integration and tests, AO simulations and performance, prototyping) and the different SCAO subsystems (pyramid wavefront sensor, calibration unit, real-time computer, dichroic and the so-called Green Doughnut which hosts the SCAO assembly as well as the MAORY MCAO natural guide star wavefront sensors).

The objective of the study was to investigate the first-night treatment success of a nasopharyngeal stent compared to standard nCPAP-titration. This is a case series and a single-center study. Eight participants (n = 8) were selected with untreated obstructive sleep apnea with a prestudy AHI ≥ 10. A newly developed nasopharyngeal stent was tested individually versus standard nCPAP-titration. Cardiorespiratory polysomnography was performed on two consecutive nights (random order: stent, nCPAP). The AHI, the number of obstructive apneas and hypopneas, the mean oxygen saturation, and the minimum oxygen saturation were compared before and after using the nasopharyngeal stent or standard nCPAP. The AHI value before treatment (AHIpre) was 31.1 ± 12.0 (mean ± standard deviation). After inserting the AlaxoStent, the mean AHIstent was 19 ± 12.0 compared to mean AHInCPAP 8.2 ± 11.9 with standard nCPAP-titration. Both nasopharyngeal stenting and nCPAP-titration could reduce the mean number of obstructive apneas by >94 %. Compared to responder rates of classic surgical interventions like uvulopalatopharyngoplasty or multi-level surgery, the nasopharyngeal stent seems to give a comparable responder rate of 50 %. There were no complications associated with the use of the stent and it was well tolerated by all subjects. Nasopharyngeal stenting widens the range of non-invasive mechanical treatment and seems to be an effective mechanical therapeutic alternative to surgery in nCPAP non-compliant patients with OSA. Careful selection of the patient population is a prerequisite of treatment and therefore it should be reserved for individual cases only.

MICADO will enable the ELT to perform diffraction limited near-infrared observations at first light. The instrument's capabilities focus on imaging (including astrometric and high contrast) as well as single object spectroscopy. This contribution looks at how requirements from the observing modes have driven the instrument design and functionality. Using examples from specific science cases, and making use of the data simulation tool, an outline is presented of what we can expect the instrument to achieve., Comment: Proc SPIE 10702. SPIE's copyright notice: "Copyright 2018 Society of PhotoOptical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited."

ERIS is an instrument that will both extend and enhance the fundamental diffraction limited imaging and spectroscopy capability for the VLT. It will replace two instruments that are now being maintained beyond their operational lifetimes, combine their functionality on a single focus, provide a new wavefront sensing module that makes use of the facility Adaptive Optics System, and considerably improve their performance. The instrument will be competitive with respect to JWST in several regimes, and has outstanding potential for studies of the Galactic Center, exoplanets, and high redshift galaxies. ERIS had its final design review in 2017, and is expected to be on sky in 2020. This contribution describes the instrument concept, outlines its expected performance, and highlights where it will most excel., 12 pages, Proc SPIE 10702 "Ground-Based and Airborne Instrumentation for Astronomy VII"

This paper presents the model based optimization of the control parameters of a combined biomass-solar thermal system for heating and domestic hot water supply, designed for small residential applications. The system consists of a thermal storage with an integrated pellet burner and a heat exchanger to feed solar energy from a small collector field into the storage. By using a physical model of the existing system, the time for optimizing the control system can be reduced significantly. To optimize the given system, it was desired not to vary the system specific parameters such as the collector or the storage size. However, the control parameters (i.e.: set-points of local control loops of the combined system) of the system are supposed to be optimized. The system was simulated with the dynamic thermal simulation environment TRNSYS using validated models. Monitored data was used to estimate several model parameters. The control strategy of the off-the-shelf product was implemented using MATLAB. In this study it was clearly shown that the performance of the described system can be improved by optimizing the control parameters upon a model based approach. A complete system model was set up and the control strategy was reproduced within the simulation environment.

In order to reduce CO2 emissions related to heating purposes within the European Union, the EU-Commission is currently preparing ecodesign and energy-labeling requirements for water heaters, storage tanks, and space and combination heaters. Especially this also applies for solar assisted space heating and hot water preparation systems. In particular, there will be a new energy efficiency classification for solar hot water storage tanks, which will be rated (A+, A, B, C, …, G) according to their standing losses. We present a test set-up and procedure that is capable of determining the standing losses conform to the EU-directive and show various measurements of some state-of-the-art storage configurations. The results reveal the need for better insulation in order to achieve an A+/A-rating for state-of-the-art storage tanks. We compare the effects of employing an better insulated storage tank compared to state-of-the-art technology for a solar thermal systems by performing annual system simulations via TRNSYS. The system comprises of a 100% renewable space heating and domestic hot water pellet-solar combi-system suitable for residential buildings.

SPIFFI is an AO-fed integral field spectrograph operating as part of SINFONI on the VLT, which will be upgraded and reused as SPIFFIER in the new VLT instrument ERIS. In January 2016, we used new technology developments to perform an early upgrade to optical subsystems in the SPIFFI instrument so ongoing scientific programs can make use of enhanced performance before ERIS arrives in 2020. We report on the upgraded components and the performance of SPIFFI after the upgrade, including gains in throughput and spatial and spectral resolution. We show results from re-commissioning, highlighting the potential for scientific programs to use the capabilities of the upgraded SPIFFI. Finally, we discuss the additional upgrades for SPIFFIER which will be implemented before it is integrated into ERIS., Comment: 20 pages, 12 figures. Proceedings from SPIE Astronomical Telescopes and Instrumentation 2016

We present the current optical design of the Relay Optics (RO) dedicated to the single-conjugate adaptive optics (SCAO) mode for the first light E-ELT imaging camera MICADO. MICADO is a wide-field near-IR camera featuring a 75 arcsec field of view, with spectrographic, astrometric, and coronagraphic capabilities. It has been chosen by ESO as one of the two first-light instruments. MICADO will be optimized for the multi-conjugate adaptive optics module MAORY and will also work in SCAO mode to provide a high-level, on-axis correction (making use of the adaptive secondary M4 in the telescope). For full scientific exploitation and in a phase approach for developing AO performance at the ELT, a SCAO mode is needed for MICADO. It will be a joint development between the MICADO and MAORY consortia and in the long term integrated in MAORY. Different options are presented to accommodate different set of requirements, the development plan of MICADO and MAORY instruments will lead to the final configuration and the used of the SCAO and its RO. They allow Coronagraphic observations providing an intermediate pupil plane to accommodate an atmospheric dispersion corrector and an apodizer.

MICADO is a near-IR camera for the Europea ELT, featuring an extended field (75" diameter) for imaging, and also spectrographic and high contrast imaging capabilities. It has been chosen by ESO as one of the two first-light instruments. Although it is ultimately aimed at being fed by the MCAO module called MAORY, MICADO will come with an internal SCAO system that will be complementary to it and will deliver a high performance on axis correction, suitable for coronagraphic and pupil masking applications. The basis of the pupil masking approach is to ensure the stability of the optical transfer function, even in the case of residual errors after AO correction (due to non common path errors and quasi-static aberrations). Preliminary designs of pupil masks are presented. Trade-offs and technical choices, especially regarding redundancy and pupil tracking, are explained., SPIE 2014 Proceeding -- Montreal

The Enhanced Resolution Imager and Spectrograph (ERIS) is the next-generation adaptive optics near-IR imager and spectrograph for the Cassegrain focus of the Very Large Telescope (VLT) Unit Telescope 4, which will soon make full use of the Adaptive Optics Facility (AOF). It is a high-Strehl AO-assisted instrument that will use the Deformable Secondary Mirror (DSM) and the new Laser Guide Star Facility (4LGSF). The project has been approved for construction and has entered its preliminary design phase. ERIS will be constructed in a collaboration including the MaxPlanck Institut fur Extraterrestrische Physik, the Eidgenossische Technische Hochschule Zurich and the Osservatorio Astrofisico di Arcetri and will offer 1 – 5 μm imaging and 1 – 2.5 μm integral field spectroscopic capabilities with a high Strehl performance. Wavefront sensing can be carried out with an optical high-order NGS Pyramid wavefront sensor, or with a single laser in either an optical low-order NGS mode, or with a near-IR low-order mode sensor. Due to its highly sensitive visible wavefront sensor, and separate near-IR low-order mode, ERIS provides a large sky coverage with its 1’ patrol field radius that can even include AO stars embedded in dust-enshrouded environments. As such it will replace, with a much improved single conjugated AO correction, the most scientifically important imaging modes offered by NACO (diffraction limited imaging in the J to M bands, Sparse Aperture Masking and Apodizing Phase Plate (APP) coronagraphy) and the integral field spectroscopy modes of SINFONI, whose instrumental module, SPIFFI, will be upgraded and re-used in ERIS. As part of the SPIFFI upgrade a new higher resolution grating and a science detector replacement are envisaged, as well as PLC driven motors. To accommodate ERIS at the Cassegrain focus, an extension of the telescope back focal length is required, with modifications of the guider arm assembly. In this paper we report on the status of the baseline design. We will also report on the main science goals of the instrument, ranging from exoplanet detection and characterization to high redshift galaxy observations. We will also briefly describe the SINFONI-SPIFFI upgrade strategy, which is part of the ERIS development plan and the overall project timeline.

We present in this paper an overview of the high contrast imaging modes of the wide-field imager MICADO. MICADO is a near-IR camera for the European Extremely Large Telescope (E-ELT), featuring a wide field (75”), spectroscopic and coronagraphic capabilities. It has been chosen by ESO as one of the two first-light instruments. MICADO will be optimized for the multi-conjugate adaptive optics module MAORY and will also work in SCAO mode. This SCAO mode will provide MICADO with a high-level, on-axis correction, making use of the M4 adaptive mirror in the telescope. After presenting the scientific interest for high contrast imaging modes in MICADO, we describe the technical choices we are studying. We present the hypotheses chosen for our simulation tools and contrast as well as planet detection performance derived from this tool.

Ludwig-Maximilians-Universit¨at M¨unchen operates an astrophysical observatory on the summit of Mt. Wendelstein 1 which will be equipped with a modern 2m-class, robotic telescope. 2 One Nasmyth port of the new Fraunhofer telescope is designed to sustain the excellent (< 0.8" median) seeing of the site [1, Fig. 1] over a FOV of 0.2 deg 2 utilizing three-element transmissive field corrector optics for optical wavebands. It will be equipped with a camera built around a customized 64 MPixel Mosaic (Spectral Instruments, 4 × (4k) 2 15μm e2v CCDs). TheWendelsteinWide Field Imager has two filter wheels with eight slots each (SDSS3 [ugriz] + eight still free) as well as two off-axis guiding units (two FLI Microline with 2k Fairchild CCDs on differential focus stages). A Bonn Shutter4 ensures high precision photometric exposures. An option to either insert a low dispersion grating (for field spectroscopy) or support a wave front sensor probe allows for further expansion of the camera. EMI-safe housing has to overcome the emission of a close by 0.5MW radio station. Special care has been taken to design a very low ghost budget of the overall system to allow for low-surface brightness applications (e.g. weak lensing surveys).

Ludwig-Maximilians-Universitat Munchen operates an astrophysical observatory on the summit of Mt. Wendelstein 1 which will be equipped with a modern 2m-class, robotic telescope. The plan is to operate one of the most efficient robotic 2m telescopes in Europe in order to offer optimal scientific opportunities for our researchers and maintain highest standards for the education of students. The 2m Fraunhofer telescope in its new 8.5m dome has a modern, very compact alt.-azimuth design. Two Nasmyth ports will harbor a wide-field camera (WWFI 2 ), a medium field multi-channel camera (3kk 3 ), a low resolution IFU spectrograph (VIRUSW 4 ) and a high resolution spectrograph (upgraded FOCES 5 ). All instruments will be simultaneously ready for remote or robotic observations. The telescope is designed as a 3-mirror f /7.8 system and should maintain the excellent (< 0.8" median) seeing of the site1 over a field of view (f.o.v.) of 0.7 deg diameter with a field corrector for the wide field port at optical wavelength. The second port provides a f.o.v. of 60 arcmin 2 without any corrector optics. It is optimized for simultaneous optical and NIR imaging as well as field spectroscopy and echelle high resolution spectroscopy over the full optical wavelength regime.6 Here we present the design of the telescope as well as the scope and projected time line of the overall project.

This paper presents the mission profile as well as the optical configuration of the space-borne AsteroidFinder telescope. Its main objective is to retrieve asteroids with orbits interior to Earth’s orbit. The instrument requires high sensitivity to detect asteroids with a limiting magnitude of equal or larger than 18.5mag (V-Band) and astrometric accuracy of 1arcsec (1σ). This requires a telescope aperture greater than 400cm², high image stability, detectors with high quantum efficiency (peak > 90%) and very low noise, which is only limited by zodiacal background. The telescope will observe the sky between 30° and 60° in solar elongation. The telescope optics is based on a Cook type TMA. An effective 2°×2° field of view (FOV) is achieved by a fast F/3.4 telescope with near diffraction-limited performance. The absence of center obscuration or spiders in combination with an accessible intermediate field plane and exit pupil allow for efficient stray light mitigation. Design drivers for the telescope are the required point spread function (PSF) values, an extremely efficient stray light suppression (due to the magnitude requirement mentioned above), the detector performance, and the overall optical and mechanical stability for all orientations of the satellite. To accommodate the passive thermal stabilization scheme and the necessary structural stability, the materials selection for the telescope main structure and the mirrors are of vital importance. A focal plane with four EMCCD detectors is envisaged. The EMCCD technology features shorter integration times, which is in favor regarding the pointing performance of the satellite. The launch of the mission is foreseen for the year 2013 with a subsequent mission lifetime of at least 1 year.

CD34 most probably acts as a receptor molecule on hematopoietic progenitor cells; however, its precise function remains to be elucidated. To track the intracellular pathway of CD34 after binding of a stimulatory antibody (anti-HPCA-1), immuno-electron microscopical analysis was performed on cells of normal bone marrow (NBMPC), acute leukemias, and the KG1a cell line. Before stimulation, CD34 was evenly distributed over the cell surface. After binding of the anti-HPCA-1, but not the anti-HPCA-2 antibody to CD34 and labeling with 30-nm immunogold, a rapid capping of CD34 and a subsequent internalization from the cell surface via clathrin-coated pits and coated vesicles was observed. The percentage of internalized CD34/immunogold complexes ranged from 8 to 80% in the NBMPC and the leukemic blasts, whereas KG1a cells showed an internalization rate of only 0.42%. Moreover, in the KG1a cells, the CD34/immunogold complexes were not associated with the coated pits. These differences in CD34 internalization did not correlate to the mRNA expression for the full-length or truncated CD34 assessed by isotype-specific real-time PCR. Taken together, evidence was found that CD34 is a surface receptor molecule that is modulated by receptor-mediated endocytosis. CD34 on KG1a cells appears to have a functional and/or structural defect, preventing modulation of this epitope.