The Earth’s Gamma-ray Albedo as observed by EGRET

Petry, D.

doi:10.1063/1.1878488

“…It is produced by decay of π 0 pions (mainly above 50 MeV), by bremsstrahlung from primary and secondary electrons (mainly below 50 MeV), and also by the reflection of CXB and it has been measured by several satellites and balloon experiments. 60,61,63,64,69,75,76,78,82,87,[172][173][174][175][176][177] The intensity depends on the geomagnetic latitude. 178 We utilize a model reported by Ajello et ) and after some corrections with measurements by the polar-orbiting satellite 1972-076B 178 (h ∼ 750 km).…”

Section: Albedo X-rays/γ-raysmentioning

confidence: 99%

Simulations of expected signal and background of gamma-ray sources by large field-of-view detectors aboard CubeSats

Galgóczi

¹

,

Řípa

²

,

Campana

³

et al. 2021

J. Astron. Telesc. Instrum. Syst.

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In recent years the number of CubeSats (U-class spacecrafts) launched into space has increased exponentially marking the dawn of the nanosatellite technology. In general these satellites have a much smaller mass budget compared to conventional scientific satellites which limits shielding of scientific instruments against direct and indirect radiation in space.In this paper we present a simulation framework to quantify the signal in large field-of-view gamma-ray scintillation detectors of satellites induced by X-ray/gamma-ray transients, by taking into account the response of the detector. Furthermore, we quantify the signal induced by X-ray and particle background sources at a Low-Earth Orbit outside South Atlantic Anomaly and polar regions. Finally, we calculate the signal-to-noise ratio taking into account different energy threshold levels. Our simulation can be used to optimize material composition and predict detectability of various astrophysical sources by CubeSats.We apply the developed simulation to a satellite belonging to a planned CAMELOT CubeSat constellation. This project mainly aims to detect short and long gamma-ray bursts (GRBs) and as a secondary science objective, to detect soft gamma-ray repeaters (SGRs) and terrestrial gamma-ray flashes (TGFs). The simulation includes a detailed computer-aided design (CAD) model of the satellite to take into account the interaction of particles with the material of the satellite as accurately as possible.Results of our simulations predict that CubeSats can complement the large space observatories in high-energy astrophysics for observations of GRBs, SGRs and TGFs. For the detectors planned to be on board of the CAMELOT CubeSats the simulations show that detections with signal-to-noise ratio of at least 9 for median GRB and SGR fluxes are achievable.

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“…It is produced by decay of π 0 pions (mainly above 50 MeV), by bremsstrahlung from primary and secondary electrons (mainly below 50 MeV), and also by the reflection of CXB and it has been measured by several satellites and balloon experiments. 60,61,63,64,69,75,76,78,82,87,[172][173][174][175][176][177] The intensity depends on the geomagnetic latitude. 178 We utilize a model reported by Ajello et ) and after some corrections with measurements by the polar-orbiting satellite 1972-076B 178 (h ∼ 750 km).…”

Section: Albedo X-rays/γ-raysmentioning

confidence: 99%

Simulations of expected signal and background of gamma-ray sources by large field-of-view detectors aboard CubeSats

Galgóczi,

Řípa,

Campana

et al. 2021

Preprint

0

View full text Add to dashboard Cite

In recent years the number of CubeSats (U-class spacecrafts) launched into space has increased exponentially marking the dawn of the nanosatellite technology. In general these satellites have a much smaller mass budget compared to conventional scientific satellites which limits shielding of scientific instruments against direct and indirect radiation in space.In this paper we present a simulation framework to quantify the signal in large field-of-view gamma-ray scintillation detectors of satellites induced by X-ray/gamma-ray transients, by taking into account the response of the detector. Furthermore, we quantify the signal induced by X-ray and particle background sources at a Low-Earth Orbit outside South Atlantic Anomaly and polar regions. Finally, we calculate the signal-to-noise ratio taking into account different energy threshold levels. Our simulation can be used to optimize material composition and predict detectability of various astrophysical sources by CubeSats.We apply the developed simulation to a satellite belonging to a planned CAMELOT CubeSat constellation. This project mainly aims to detect short and long gamma-ray bursts (GRBs) and as a secondary science objective, to detect soft gamma-ray repeaters (SGRs) and terrestrial gamma-ray flashes (TGFs). The simulation includes a detailed computer-aided design (CAD) model of the satellite to take into account the interaction of particles with the material of the satellite as accurately as possible.Results of our simulations predict that CubeSats can complement the large space observatories in high-energy astrophysics for observations of GRBs, SGRs and TGFs. For the detectors planned to be on board of the CAMELOT CubeSats the simulations show that detections with signal-to-noise ratio of at least 9 for median GRB and SGR fluxes are achievable.

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“…Dashed lines correspond to geometry areas of detectors. Spectrometer (AMS) (Alcaraz et al, 2000), CDGR and the Earth gamma-ray albedo spectra measured by Swift/BAT and CGRO/EGRET instruments (Ajello et al, 2008;Perty, 2005), calculated spectra of the Earth neutron albedo represented in Drozdov et al (2010) were used. We also used LaBr 3 (Ce) intrinsic activity spectrum for the LES detector background estimation (Quarati et al, 2012).…”

Section: Response Simulationmentioning

confidence: 99%