The importance of electron–electron bremsstrahlung for terrestrial gamma-ray flashes, electron beams and electron–positron beams

The detection of optical rebrightenings and X-ray plateaus in the afterglows of gamma-ray bursts (GRBs) challenges the generic external shock model. Recently, we have developed a numerical method to calculate the dynamics of the system consisting of a forward shock and a reverse shock. Here, we briefly review the applications of this method in the afterglow theory. By relating these diverse features to the central engines of GRBs, we find that the steep optical rebrightenings would be caused by the fall-back accretion of black holes, while the shallow optical rebrightenings are the consequence of the injection of the electron-positron-pair wind from the central magnetar. These studies provide useful ways to probe the characteristics of GRB central engines.

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X-ray and Gamma-ray Radiation from the Switched-off Radiopulsars

Symposium - International Astronomical Union ◽

10.1017/s0074180900034355 ◽

1983 ◽

Vol 101 ◽

pp. 505-507

Author(s):

A. I. Tsygan

Keyword(s):

Neutron Stars ◽

Magnetic Dipole ◽

Gamma Ray ◽

Neutral Hydrogen ◽

Dipole Radiation ◽

X Ray ◽

Electron Positron ◽

Hard Radiation ◽

Γ Ray ◽

Generate Electron

It is shown that pulsars that have ceased to generate electron-positron pairs (switched-off radiopulsars) may be the sources of X-ray and γ-ray radiation. The magnetic dipole radiation from these rotating neutron stars is transformed near the “light radius” into hard radiation by the plasma that is created due to ionization of interstellar neutral hydrogen.

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TARANIS XGRE and IDEE Detection Capability of Terrestrial Gamma-Ray Flashes and Associated Electron Beams

10.5194/gi-2017-1 ◽

2017 ◽

Cited By ~ 1

Author(s):

David Sarria ◽

Francois Lebrun ◽

Pierre-Louis Blelly ◽

Remi Chipaux ◽

Philippe Laurent ◽

...

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Energy Range ◽

Gamma Rays ◽

Gamma Ray ◽

Electron Beams ◽

Effective Area ◽

Detection Rates ◽

Transient Phenomena ◽

Preliminary Model

Abstract. With a launch expected in 2018, the TARANIS micro-satellite is dedicated to the study of transient phenomena observed in association with thunderstorms. On-board the spacecraft, XGRE and IDEE are two instruments dedicated to study Terrestrial Gamma-ray Flashes (TGFs) and associated electron beams (TEBs). XGRE can detect electrons (energy range: 1 MeV to 10 MeV) and X/gamma-rays (energy range: 20 keV to 10 MeV), with a very high counting capability (about 10 million counts per second), and the ability to discriminate one type of particle from the other. The IDEE instrument is focused on electrons in the 80 keV to 4 MeV energy range, with the ability to estimate their pitch angles. Monte-Carlo simulations of the TARANIS instruments, using a preliminary model of the spacecraft, allow sensitive area estimates for both instruments. It leads to an averaged effective area of 425 cm2 for XGRE to detect X/gamma rays from TGFs, and the combination of XGRE and IDEE gives an average effective area of 255 cm2 to detect electrons/positrons from TEBs. We then compare these performances to RHESSI, AGILE, and Fermi GBM, using performances extracted from literature for the TGF case, and with the help of Monte-Carlo simulations of their mass models for the TEB case. Combining these data with with the help of the MC-PEPTITA Monte-Carlo simulations of TGF propagation in the atmosphere, we build a self-consistent model of the TGF and TEB detection rates of RHESSI, AGILE, and Fermi. It can then be used to estimate that TARANIS should detect about 225 TGFs/year and 25 TEBs/year.

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CEPC Linac design

International Journal of Modern Physics A ◽

10.1142/s0217751x19400050 ◽

2019 ◽

Vol 34 (13n14) ◽

pp. 1940005 ◽

Cited By ~ 1

Author(s):

Cai Meng ◽

Jingru Zhang ◽

Xiaoping Li ◽

Guoxi Pei ◽

Dou Wang ◽

...

Keyword(s):

Dynamic Simulation ◽

Repetition Frequency ◽

Positron Source ◽

Electron Positron ◽

Transport Line ◽

Simulation Results ◽

Positron Beams

The Circular Electron–Positron Collider (CEPC) is a 100-km ring [Formula: see text] collider for a Higgs factory. The injector of CEPC is composed of Linac and Booster. The Linac is a normal conducting S-band Linac with a frequency of 2860 MHz; it provides electron and positron beams at an energy of up to 10 GeV with 100 Hz repetition frequency of 100 Hz. The Linac design and dynamic simulation results are discussed in detail in this paper, including electron bunching system, positron source, electron bypass transport line, damping ring and main Linacs.

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Modes of Energy Loss from Isolated Magnetized Neutron Star

Symposium - International Astronomical Union ◽

10.1017/s0074180900161121 ◽

1987 ◽

Vol 125 ◽

pp. 450-450

Author(s):

S. Shibata

Keyword(s):

Magnetic Field ◽

Neutron Star ◽

Gamma Ray ◽

Rotational Energy ◽

Pair Creation ◽

Dipole Radiation ◽

Pair Plasma ◽

Electron Positron ◽

Closed Current ◽

Electron Positron Pair

Pulsar may be regarded as a discharge tube by electron-positron pair creation. On this viewpoint we carry out two numerical calculations. The obtained magnetic field is consistent with the flow. We find that pulsars emit their rotational energy through three modes simultaneously. The three modes are (1)relativistic acceleration and following gamma-ray emission in the closed current circuit in the magnetosphere, (2)wind of the electron-positron pair plasma, and (3)dipole radiation.

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Indirect effects of dark matter

International Journal of Modern Physics D ◽

10.1142/s0218271819410116 ◽

2019 ◽

Vol 28 (13) ◽

pp. 1941011 ◽

Cited By ~ 4

Author(s):

K. M. Belotsky ◽

E. A. Esipova ◽

A. Kh. Kamaletdinov ◽

E. S. Shlepkina ◽

M. L. Solovyov

Keyword(s):

Dark Matter ◽

Indirect Effects ◽

Large Scale ◽

Gamma Ray ◽

Space Distribution ◽

Stable Form ◽

Final State ◽

Electron Positron ◽

Text Mode ◽

The Universe

Here, we briefly review possible indirect effects of dark matter (DM) of the universe. It includes effects in cosmic rays (CR): first of all, the positron excess at [Formula: see text]500[Formula: see text]GeV and possible electron–positron excess at 1–1.5[Formula: see text]TeV. We tell that the main and least model-dependent constraint on such possible interpretation of CR effects goes from gamma-ray background. Even ordinary [Formula: see text] mode of DM decay or annihilation produces prompt photons (FSR) so much that it leads to contradiction with data on cosmic gamma-rays. We present our attempts to possibly avoid gamma-ray constraint. They concern with peculiarities of both space distribution of DM and their physics. The latter involves complications of decay/annihilation modes of DM, modifications of Lagrangian of DM-ordinary matter interaction and inclusion of mode with identical fermions in final state. In this way, no possibilities to suppress were found except, possibly, the mode with identical fermions. While the case of spatial distribution variation allows achieving consistency between different data. Also, we consider stable form of DM which can interact with baryons. We show which constraint such DM candidate can get from the damping effect in plasma during large-scale structure (LSS) formation in comparison with other existing constraints.

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