Abstract-We have developed and tested several prototypes of GEM-like detectors with electrodes coated with resistive layers or completely made of resistive materials. These detectors can operate stably at gains close to 10 5 . The resistive layers limit the energy of discharges appearing at higher gains thus making the detectors very robust. We demonstrated that the cathodes of some of these detectors could be coated by CsI or SbCs layers to enhance the detection efficiency for the UV and visible photons. We also discovered that such detectors can operate stably in the cascade mode and high overall gains ( 10 6 ) are reachable. Applications in several areas, for example in RICH or in noble liquid TPCs are therefore possible. The first results from the detection of UV photons at room and cryogenic temperatures will be given.Index Terms-CsI photocathode, GEM, noble liquids TPC.

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In this study we present first results from a new detector of UV photons: a thick gaseous electron multiplier (GEM) with resistive electrodes, combined with CsI or CsTe/CsI photocathodes.The hole-type structure considerably suppresses the photon and ion feedback, whereas the resistive electrodes protect the detector and the readout electronics from damage by any eventual discharges.This device reaches higher gains than a previously developed photosensitive RPC and could be used not only for the imaging of UV sources, flames or Cherenkov light, for example, but also for the detection of X-rays and charged particles.

In this report, the results of a study on the effects of compositional variations induced by the small changes in concentrations of the parent components and/or by the substitution of Ni, Mn, or In by an extra element Z, on the phase transitions, and phenomena related to the magnetostructural transitions in off-stoichiometric Ni-Mn-In based Heusler alloys are summarized. The crystal structures, phase transitions temperatures, and magnetic and magnetocaloric properties were analyzed for representative samples of the following systems (all near 15 at.% indium concentration):

The impact of B substitution in Ni50Mn35In15−xBx Heusler alloys on the structural, magnetic, transport, and parameters of the magnetocaloric effect (MCE) has been studied by means of room-temperature X-ray diffraction and thermomagnetic measurements (in magnetic fields (H) up to 5 T, and in the temperature interval 5–400 K). Direct adiabatic temperature change (ΔTAD) measurements have been carried out for an applied magnetic field change of 1.8 T. The transition temperatures (T-x) phase diagram has been constructed for H = 0.005 T. The MCE parameters were found to be comparable to those observed in other MCE materials such as Ni50Mn34.8In14.2B and Ni50Mn35In14X (X=In, Al, and Ge) Heusler alloys. The maximum absolute value of ΔTAD = 2.5 K was observed at the magnetostructural transition for Ni50Mn35In14.5B0.5.