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تسجيل مستخدم جديدThe gas pixel detector as a solar X-ray polarimeter and imager
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The Sun is the nearest astrophysical source with a very intense emission in the X-ray band. The study of energetic events, such as solar flares, can help us to understand the behaviour of the magnetic field of our star. There are in the literature numerous studies published about polarization predictions, for a wide range of solar flares models involving the emission from thermal and/or non-thermal processes, but observations in the X-ray band have never been exhaustive. The gas pixel detector (GPD) was designed to achieve X-ray polarimetric measurements as well as X-ray images for far astrophysical sources. Here we present the possibility to employ this instrument for the observation of our Sun in the X-ray band.
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The Gamma-Ray Imager/Polarimeter for Solar flares (GRIPS) is a balloon-borne telescope designed to study solar-flare particle acceleration and transport. We describe GRIPSs first Antarctic long-duration flight in Jan 2016 and report preliminary calib
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The Gas Pixel Detector, recently developed and continuously improved by Pisa INFN in collaboration with IASF-Roma of INAF, can visualize the tracks produced within a low Z gas by photoelectrons of few keV. By reconstructing the impact point and the o
riginal direction of the photoelectrons, the GPD can measure the linear polarization of X-rays, while preserving the information on the absorption point, the energy and the time of individual photons. Applied to X-ray Astrophysics, in the focus of grazing incidence telescopes, it can perform angular resolved polarimetry with a huge improvement of sensitivity, when compared with the conventional techniques of Bragg diffraction at 45 degrees and Compton scattering around 90 degrees. This configuration is the basis of POLARIX and HXMT, two pathfinder missions, and is included in the baseline design of IXO, the very large X-ray telescope under study by NASA, ESA and JAXA.
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shelf (COTS) X-ray spectrometer from Amptek to measure the solar irradiance from 0.5 to 30 keV with a nominal 0.15 keV FWHM spectral resolution at 5.9 keV, and a LASP-developed X-ray broadband photometer with similar spectral sensitivity. MinXSS design and development has involved over 40 graduate students supervised by professors and professionals at the University of Colorado at Boulder. The majority of previous solar soft X-ray measurements have been either at high spectral resolution with a narrow bandpass or spectrally integrating (broadband) photometers. MinXSS will conduct unique soft X-ray measurements with moderate spectral resolution over a relatively large energy range to study solar active region evolution, solar flares, and the effects of solar soft X-ray emission on Earths ionosphere. This paper focuses on the X-ray spectrometer instrument characterization techniques involving radioactive X-ray sources and the National Institute for Standards and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF). Spectrometer spectral response, spectral resolution, response linearity are discussed as well as future solar science objectives.
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