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The employment of large arrays of microcalorimeters in space missions (IXO, EDGE/XENIA)[1][2][3], requires the presence of an anticoincidence detector to remove the background due to the particles, with a rejection efficiency at least equal to Suzaku (98%) [1]. A new concept of anticoincidence is under development to match the very tight thermal requirements and to simplify the design of the electronic chain. The idea is to produce a Cryo-AntiCoincidence (Cryo-AC) based on a silicon absorber and read by a TES (Transition-Edge Sensor). This configuration would ensure very good performances in terms of efficiency, time response and signal to noise ratio. We present the results of estimations, simulations and preliminary measurement. [ABSTRACT FROM AUTHOR]

SQUIDs readout electronics for TES microcalorimeters are generally based on the standard Flux Locked Loop scheme in which the SQUID is inserted in a feedback circuit in order to increase its Dynamic Range. For those applications in which a high loop gain at high frequency is needed, such as FDM multiplexing of a large number of pixels, the distance between the SQUID and room temperature electronics limits the performances due to the finite propagation time of the signal. Here we present a solution in which the feedback electronics is located in the cryogenic environment as close as possible to the SQUID. In particular we adopt a scheme in which the feedback loop is split in two paths: a high frequency FLL loop in cryogenic environment and a low frequency loop which is closed at room temperature. With this approach it is not necessary to have a precision DC amplifier working at cryogenic temperatures, resulting in a substantial simplification of the cryogenic components of the electronics. This paper describes the theory behind and the experimental work which is currently carried out to prove this concept. [ABSTRACT FROM AUTHOR]

The IMXS (Interstellar and intergalactic Medium X-ray Survey) — BOSS (gamma-ray Burst Observatory and Spectroscopy Survey) is an experiment proposed to fly on the ISS (International Space Station), in order to perform an all-sky survey to study the diffuse X-ray emission and to measure the spectra of Gamma-Ray Bursts (GRB) with high energy resolution in the 0.1-10 keV energy range. In a 3 years lifetime mission, the experiment will detect about 20 to 40 GRBs. In several events, we can perform high resolution spectroscopy of the iron emission lines and absorption edges. Such components have been observed by BeppoSAX and Chandra. The measurements of these features would provide a direct diagnostic of the physical and kinematical state of the medium surrounding a GRB. Furthermore, they would supply information about the origin of the progenitors of the GRBs (probably a supernova explosion of massive stars) and their site formation (possibly a star-forming region). [ABSTRACT FROM AUTHOR]

The IMBOSS (Interstellar/Intergalactic Medium and gamma-ray Burst Observatory and Spectroscopy Survey) is an experiment proposed to fly on the ISS (International Space Station), in order to perform an allsky survey to study the diffuse X-ray emission and to measure the spectra of Gamma-Ray Bursts (GRB) with high energy resolution in the 0.1-10 kev energy range. In a 3-year mission, the experiment will detect about 20 to 40 GRBs. In several events, we can perform high resolution spectroscopy of the iron emission lines and absorption edges. Such components have been observed by BeppoSAX and Chandra. The measurements of these features would provide a direct diagnostic of the physical and kinematical state of the medium surrounding a GRB. Furthermore, they would supply information about the origin of the progenitors of the GRBs (probably a supernova explosion of massive stars) and their site formation (possibly a star-forming region). [ABSTRACT FROM AUTHOR]