Detection of Crab radiation with a meteorological balloon borne phoswich detector

Abstract

We use existing light weight balloon facility of Indian Centre for Space Physics to detect the X-ray radiation from Crab pulsar with a phoswich detector. We present the design considerations and characterization of the detector used for this purpose. We model the background radiation in the detector environment at various altitudes and use this in spectral analysis. The background radiation level and limitations on the detector allowed us to calculate minimum detection limit for extrasolar radiation sources with our set up.Keywords X-and γ-ray telescopes and instrumentation · Background radiations · Observation and data reduction techniques; computer modeling and simulation · Astronomical and space-research instrumentation PACS 95.55.Ka · 98.70.Vc · 95.75.-z · 95.55.-n

Development of instruments for space exploration using meteorological balloons

“…From the previous background measurement experiment, we calculated the minimum sensitivity of the detector at 40 km and in the energy range of 20-60 keV is ∼ 200 mCrab. 21 There was no other source brighter than this inside the FoV (15 • ) of the detector during the experiment, which was confirmed using other all sky monitor data onboard satellite (Swift/BAT 22 ). So, the excess radiation which is well beyond 3σ significance level at the peak from the background is indeed from Crab pulsar.…”

“…Our data quality is decided by the shielding materials. 21 The test and evaluation procedure of every instrument is done very strictly. We also carry out calibration of these instruments in near space conditions by simulating in-flight pressure and temperature variations.…”

“…The time-stamped and attitude tagged photons are analyzed keeping in mind different levels of atmospheric absorption at different altitudes. 21 These details are beyond the scope of this paper and will be presented elsewhere.…”

Study of Secondary Cosmic Rays and Astronomical X-Ray Sources using Small Stratospheric Balloons

“…External background radiations are the incoming counts consisting of downward and upward secondary CRs, mainly gamma photons (Sarkar et al 2019). Internal radiation may be produced by gamma-ray scattering with detector crystals, Compton scattering, pair production, photons escaping due to annihilation, (Peterson et al 1972) etc.…”

“…Therefore, we have to model background radiation, which is based on our previous empirical model discussed . The background model present in Sarkar et al (2019) is used in the Sikdar et al (2023c) work and is also verified by the detailed calculations presented in Sarkar et al (2020) and Sikdar et al (2023a). We considered the detector background spectral range from altitude 20 to 30 km in each atmospheric layer of 1 km as normal backgrounds, as stated in Sarkar et al (2019).…”