The Application Potential of Silicon Photomultipliers for a Camera of a Small-Size Cherenkov Gamma-Ray Telescope for Reducing the Detection Threshold

Searches for “dark” subhaloes in gamma-ray point-like source catalogues are among promising strategies for indirect dark matter detection. Such a search is nevertheless affected by uncertainties related, on the one hand, to the modelling of the dark matter subhalo distribution in Milky-Way-like galaxies, and, on the other hand, to the sensitivity of gamma-ray instruments to the dark matter subhalo signals. In the present work, we assess the detectability of dark matter subhaloes in Fermi-LAT catalogues, taking into accounts uncertainties associated with the modelling of the galactic subhalo population. We use four different halo models bracketing a large set of uncertainties. For each model, adopting an accurate detection threshold of the LAT to dark matter subhalo signals and comparing model predictions with the number of unassociated point-sources in Fermi-LAT catalogues, we derive upper limits on the annihilation cross section as a function of dark matter mass. Our results show that, even in the best-case scenario (i.e., DMonly subhalo model), which does not include tidal disruption from baryons, the limits on the dark matter parameter space are less stringent than current gamma-ray limits from dwarf spheroidal galaxies. Comparing the results obtained with the different subhalo models, we find that baryonic effects on the subhalo population are significant and lead to dark matter constraints that are less stringent by a factor of ∼2 to ∼5. This uncertainty comes from the unknown resilience of dark matter subhaloes to tidal disruption.

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Gamma-ray production in selected Wolf-Rayet binaries

Symposium - International Astronomical Union ◽

10.1017/s0074180900211765 ◽

2003 ◽

Vol 212 ◽

pp. 150-151

Author(s):

Paula Benaglia ◽

Gustavo E. Romero

Keyword(s):

Particle Acceleration ◽

Gamma Ray ◽

Thermal Flux ◽

Detection Threshold ◽

High Energy ◽

Early Type ◽

Acceleration Region ◽

Thermal Radio Emission ◽

Inverse Compton ◽

Γ Ray

In the colliding wind region of early-type binaries, electrons can be accelerated up to relativistic energies, as demonstrated by the detection of non-thermal radio emission from several WR+OB systems. The particle acceleration region is exposed to strong photon fields, and inverse-Compton cooling of the electrons could result in a substantial high-energy non-thermal flux. We present here preliminary results of a study of the binaries WR 140, WR 146, and WR 147 in the light of recent radio and γ-ray observations. We show that under reasonable assumptions WR 140 can produce the γ-ray flux from the GRO-egret source 3EG J 2022+4317. WR 146 and WR 147 are below the detection threshold.

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A Complete Mission Concept Design and Analysis of the Student-Led CubeSat Project: Light-1

Aerospace ◽

10.3390/aerospace8090247 ◽

2021 ◽

Vol 8 (9) ◽

pp. 247

Author(s):

Aaesha Almazrouei ◽

Aaliya Khan ◽

Abdullah Almesmari ◽

Ahmed Albuainain ◽

Ahmed Bushlaibi ◽

...

Keyword(s):

United Arab Emirates ◽

Electric Fields ◽

Gamma Rays ◽

Gamma Ray ◽

Thunderstorm Activity ◽

Low Earth Orbit ◽

Concept Design ◽

Silicon Photomultipliers ◽

Strong Electric Fields ◽

Future Plans

Terrestrial gamma ray flashes (TGF) are intense and prompt bursts of X- and gamma-rays of up to 100 MeV of energy. Typically associated with thunderstorm activity, TGFs are produced by bremsstrahlung effects of electrons accelerated in strong electric fields generated by lightning. TGFs can be effectively targeted by gamma detectors with enhanced time stamping capabilities onboard of satellites operating at near-Earth low obits (LEO) [1]. Light-1 is a miniature satellite, a 3U CubeSat designed to detect, monitor and study terrestrial gamma ray flashes in low Earth orbit. The two payload detectors are composed of a photomultiplier tube and silicon photomultipliers. The two detectors are mounted at two ends of the CubeSat and the proposed orientation of the CubeSat will ensure maximum TGF detection probability. To allow an increased frequency of data downlink, Khalifa University has collaborated with NanoAvionics Corp, and hence Light-1 has access to three ground stations situated across the map, Abu Dhabi in United Arab Emirates, Vilnius in Lithuania, and Aalborg in Denmark. The satellite expected to launch in late-2021 is currently in its assembly and integration phase. This paper describes mission, concept, objectives, success criteria, design, analysis, status, and the future plans of Light-1 satellite.

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Modelling of SiPM Performance for Detection of Cherenkov Radiation from Extensive Air Showers in UV and Visible Ranges for Application at the TAIGA-IACT Telescope

Latvian Journal of Physics and Technical Sciences ◽

10.2478/lpts-2020-0002 ◽

2020 ◽

Vol 57 (1-2) ◽

pp. 13-21 ◽

Cited By ~ 2

Author(s):

A.A. Bogdanov ◽

E.E. Kholupenko ◽

Yu.V. Tuboltsev ◽

Yu.V. Chichagov

Keyword(s):

Background Noise ◽

Cherenkov Radiation ◽

Gamma Ray ◽

Detection Efficiency ◽

Extensive Air Showers ◽

Visible Range ◽

Air Showers ◽

Silicon Photomultipliers ◽

High Background ◽

Low Amplitude

AbstractA novel cluster of sensitive detectors based on silicon photomultipliers (SiPM) is being developed for the Cherenkov gamma-ray telescope TAIGA-IACT (Tunka valley, Republic of Buryatia, Russia). The cluster will be able to detect Cherenkov radiation from extensive air showers in two wide bands: 250–300 nm (UV) and 250–700 nm (visible and UV). Each pixel consists of a Winston cone, 4 SiPMs with the total sensitive area of 144 mm2, and readout electronics based on fast analogue memory. During operation in the UV band, a UV-bandpass filter is used to suppress cluster sensitivity in the visible range. In order to evaluate the detection efficiency of the selected SiPMs, a specific software simulator of SiPM output signal has been developed. This simulator takes into account such inherent parameters of SiPMs as total number of microcells, their recharge time, the dark count rate, the effective detection area, the quantum efficiency, the crosstalk between microcells, as well as conditions of SiPM operation, namely, the background noise and the Ohmic load in the readout (front-end) electronics. With this simulator it is possible to determine the expected trigger threshold under given conditions and parameters of selected detectors. Based on preliminary simulations, OnSemi MicroFJ-60035 SiPM chips have been chosen for the novel cluster of TAIGA-IACT. These SiPMs have sensible efficiency in the ultraviolet range (5–20% in the 250–300 nm band) and are distinguished by the presence of a fast output, which allows one to capture a low amplitude signal above a relatively high background noise.

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Investigation of parameters of new MAPD-3NM silicon photomultipliers

Journal of Instrumentation ◽

10.1088/1748-0221/17/01/c01001 ◽

2022 ◽

Vol 17 (01) ◽

pp. C01001

Author(s):

F. Ahmadov ◽

G. Ahmadov ◽

R. Akbarov ◽

A. Aktag ◽

E. Budak ◽

...

Keyword(s):

High Energy Physics ◽

Gamma Ray ◽

Detection Efficiency ◽

High Energy ◽

Efficiency Gain ◽

Space Application ◽

Silicon Photomultipliers ◽

Photon Detection ◽

Photon Detection Efficiency ◽

Energy Physics

Abstract In the presented work, the parameters of a new MAPD-3NM-II photodiode with buried pixel structure manufactured in cooperation with Zecotek Company are investigated. The photon detection efficiency, gain, capacitance and gamma-ray detection performance of photodiodes are studied. The SPECTRIG MAPD is used to measure the parameters of the MAPD-3NM-II and scintillation detector based on it. The obtained results show that the newly developed MAPD-3NM-II photodiode outperforms its counterparts in most parameters and it can be successfully applied in space application, medicine, high-energy physics and security.

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