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The Micro-X High Resolution Microcalorimeter X-ray Imaging Rocket is a sounding rocket experiment that will combine a transition-edge-sensor X-ray-microcalorimeter array with a conical imaging mirror to obtain high- spectral-resolution images of extended X-ray sources. The target for Micro-X’s first flight (slated for January 2013) is the Puppis A supernova remnant. The Micro-X observation of the bright eastern knot of Puppis A will obtain a line-dominated spectrum with up to 27,000 counts collected in 300 seconds at 2 eV resolution across the 0.3-2.5 keV band. Micro-X will determine the thermodynamic and ionization state of the plasma, search for line shifts and broadening associated with dynamical processes, and seek evidence of ejecta enhancement. We describe the progress made in developing this payload, including the detector, cryogenics, and electronics assemblies.

The Micro‐X Imaging X‐ray Spectrometer is a sounding rocket payload slated for launch in 2011. An array of Transition Edge Sensors, which is operated at a bath temperature of 50 mK, will be used to obtain a high resolution spectrum of the Puppis‐A supernova remnant. An Adiabatic Demagnetization Refrigerator (ADR) with a 75 gram Ferric Ammonium Alum (FAA) salt pill in the bore of a 4 T superconducting magnet provides a stable heat sink for the detector array only a few seconds after burnout of the rocket motors. This requires a cold stage design with very short thermal time constants. A suspension made from Kevlar strings holds the 255 gram cold stage in place. It is capable of withstanding loads in excess of 200 g. Stable operation of the TES array in proximity to the ADR magnet is ensured by a three‐stage magnetic shielding system which consists of a superconducting can, a high‐permeability shield and a bucking coil. The development and testing of the Micro‐X payload is well underway.

The Micro-X High Resolution Microcalorimeter X-ray Imaging Rocket is sounding rocket experiment that will combine a transition-edge-sensor X-ray-microcalorimeter array with a conical imaging mirror to obtain high-spectral-resolution images of extended and point X-ray sources. Our first target is the Puppis A supernova remnant, which will be observed in January 2011. The Micro-X observation of the bright eastern knot of Puppis A will obtain a line-dominated spectrum with up to 90,000 counts collected in 300 seconds at 2 eV resolution across the 0.3-2.5 keV band. Micro-X will utilize plasma diagnostics to determine the thermodynamic and ionization state of the plasma, to search for line shifts and broadening associated with dynamical processes, and seek evidence of ejecta enhancement. We describe the progress made in developing this payload, including the detector, cryogenics, and electronics assemblies. A detailed modeling effort has been undertaken to design a rocket-bourne adiabatic demagnetization refrigerator with sufficient magnetic shielding to allow stable operation of transition edge sensors, and the associated rocket electronics have been prototyped and tested.

High-resolution X-ray spectrometers onboard suborbital sounding rockets can search for dark matter candidates that produce X-ray lines, such as decaying keV-scale sterile neutrinos. Even with exposure times and effective areas far smaller than XMM-Newton and Chandra observations, high-resolution, wide field of view observations with sounding rockets have competitive sensitivity to decaying sterile neutrinos. We analyze a subset of the 2011 observation by the X-ray Quantum Calorimeter instrument centered on Galactic coordinates = = -  lb 165 , 5 with an effective exposure of 106 s, obtaining a limit on the sterile neutrino mixing angle of q

Epilepsy is one of the most common chronic illnesses encountered by obstetricians, affecting around 1 in 200 women attending antenatal clinics. Epilepsy and antiepileptic drugs may have significant effects on pregnancy and pregnancy may affect the epilepsy. It is therefore vital that those looking after these women have a knowledge of the potential problems.

The course of isothermal crystallization of a series of high molecular weight polyethylene oxide copolymers was studied with a microdensity balance. The comonomers, butylene and styrene oxides, ranged from 0.2 to 4 mole%; several examples of different polymerization conditions were also studied. The consequence of adding noncrystallizing components to a presumably linear polymer was observed in both melting point depression and the shape of the crystallization isotherm. From the melting points obtained on the experimental copolymers, the heat of fusion appeared to be lowered by the addition of noncrystallizable sequences. Inasmuch as the shape of the crystallization isotherm is changed when different amounts of comonomers are present in a random copolymer, an estimate can be made of the amount of noncrystallizing polymer acting like a block from the crystallization kinetics data and the melting point depression.

The Micro‐X sounding rocket payload will be launched on January 18, 2011 to make the first observation of an astronomical target with Transition‐Edge Sensor (TES) X‐ray microcalorimeters. The 128 pixel TES array lies at the focus of a 2.165 m focal length conical imaging mirror with a 0.2–3.0 keV bandpass. The spectral resolution of the TES array will be between 2 and 4 eV at 1 keV. Our scientific program is focused on high‐spectral resolution observations of extended sources. For supernova remnants (SNRs) our scientific objectives are to map the velocity structure of the ejecta, and study both elemental abundances and the thermodynamic and ionization state of the plasma through plasma line diagnostics. For clusters of galaxies, Micro‐X can uniquely study turbulence, velocities, and the temperature phases of the plasma.For our initial flight, we have changed our target from the bright eastern knot to a recently discovered ejecta region in the Puppis A SNR. The target of the second flight in mid‐2012 is M87, the center of the Virgo Cluster. The third flight, in early 2014, will make an observation of the Cas A SNR. In this contribution we discuss the science objectives of our first flight.

The Micro‐X sounding rocket experiment will deploy an imaging transition‐edge‐sensor (TES) microcalorimeter spectrometer to observe astrophysical sources in the 0.2–3.0 keV band. The instrument has been designed at a systems level, and the first items of flight hardware are presently being built. In the first flight, planned for January 2011, the spectrometer will observe a recently discovered Silicon knot in the Puppis‐A supernova remnant. Here we describe the design of the Micro‐X science instrument, focusing on the instrument’s detector and detector assembly. The current design of the 2‐dimensional spectrometer array contains 128 close‐packed pixels with a pitch of 600 μm. The conically approximated Wolter‐1 mirror will map each of these pixels to a 0.95 arcmin region on the sky; the field of view will be 11.4 arcmin. Targeted energy resolution of the TESs is about 2 eV over the full observing band. A SQUID time‐division multiplexer (TDM) will read out the array. The detector time constants will be engineered to approximately 2 ms to match the TDM, which samples each pixel at 32.6 kHz, limited only by the telemetry system of the rocket. The detector array and two SQUID stages of the TDM readout system are accommodated in a lightweight Mg enclosure, which is mounted to the 50 mK stage of an adiabatic demagnetization refrigerator. A third SQUID amplification stage is located on the 1.6 K liquid He stage of the cryostat. An on‐board 55‐Fe source will fluoresce a Ca target, providing 3.69 and 4.01 keV calibration lines that will not interfere with the scientifically interesting energy band.