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Science with hot astrophysical plasmas
Urdampilleta, I.; Kaastra, J. S.; Mernier, F. +5 more
We present some recent highlights and prospects for the study of hot astrophysical plasmas. Hot plasmas can be studied primarily through their X-ray emission and absorption. Most astrophysical objects, from solar system objects to the largest scale structures of the Universe, contain hot gas. In general we can distinguish collisionally ionised gas…
Gaia, an all sky astrometric and photometric survey
Carrasco, J. M.
Gaia space mission includes a low resolution spectroscopic instrument to classify and parametrize the observed sources. Gaia is a full-sky unbiased survey down to about 20th magnitude. The scanning law yields a rather uniform coverage of the sky over the full mission. The data reduction is a global one over the full mission. Both sky coverage and …
Proton radiation damage assessment of a CCD for use in a Ultraviolet and Visible Spectrometer
Hathi, B.; Patel, M.; Gow, J. P. D. +2 more
This paper describes the radiation environment and radiation damage analysis performed for the Nadir and Occultation for MArs Discovery (NOMAD) Ultraviolet and Visible Spectrometer (UVIS) channel launched onboard the ExoMars Trace Gas Orbiter (TGO) in 2016. The aim of the instrument is to map the temporal and spatial variation of trace gases such …
Diagnosing transient plasma status: from solar atmosphere to tokamak divertor
Doyle, J. G.; Summers, H. P.; Giunta, A. S. +3 more
This work strongly exploits the interdisciplinary links between astrophysical (such as the solar upper atmosphere) and laboratory plasmas (such as tokamak devices) by sharing the development of a common modelling for time-dependent ionisation. This is applied to the interpretation of solar flare data observed by the UVSP (Ultraviolet Spectrometer …
In-flight calibration and verification of the Planck-LFI instrument
Bersanelli, M.; Butler, R. C.; Cuttaia, F. +40 more
In this paper we discuss the Planck-LFI in-flight calibration campaign. After a brief overview of the ground test campaigns, we describe in detail the calibration and performance verification (CPV) phase, carried out in space during and just after the cool-down of LFI. We discuss in detail the functionality verification, the tuning of the front-en…
Modeling an array of encapsulated germanium detectors
Kshetri, R.
A probability model has been presented for understanding the operation of an array of encapsulated germanium detectors generally known as composite detector. The addback mode of operation of a composite detector has been described considering the absorption and scattering of γ-rays. Considering up to triple detector hit events, we have obtained ex…
From a single encapsulated detector to the spectrometer for INTEGRAL satellite: predicting the peak-to-total ratio at high γ-energies
Kshetri, R.
In two recent papers (R. Kshetri, JINST 2012 7 P04008; ibid., P07006), a probabilistic formalism was introduced to predict the response of encapsulated type composite germanium detectors like the SPI (spectrometer for INTEGRAL satellite). Predictions for the peak-to-total and peak-to-background ratios are given at 1.3 MeV for the addback mode of o…
A first principle approach for clover detector
Kshetri, R.
A simple model based on probability flow arguments has been presented for understanding the clover germanium detector. Using basic concepts of absorption and scattering of gamma-rays, the operation of the clover detector has been described in terms of six probability amplitudes and a parameter. Instead of using an empirical method or simulation, t…
The use of swept-charge devices in planetary analogue X-ray fluorescence studies
Smith, D. R.; Walker, T. E.
The Chandrayaan-1 X-ray Spectrometer (C1XS) was launched onboard the Indian Space Research Organisation (ISRO) Chandrayaan-1 lunar mission in October 2008. The instrument consisted of 24 swept-charge device (SCD) silicon X-ray detectors providing a total collecting area of ~ 24 cm2, corresponding to a 14° field of view (FWHM), with the …