scholarly journals British plans for astronomy in Antarctica

1992 ◽  
Vol 9 ◽  
pp. 599-599
Author(s):  
R D Davies ◽  
J M Hough
Keyword(s):  
Gamma Rays ◽  
Small Area ◽  
Gamma Ray ◽  
Angular Resolution ◽  
State Of The Art ◽  
Austral Summer ◽  
Cosmic Ray ◽  
South Pole ◽  
Gamma Ray Astronomy ◽  
Air Shower

The South Pole air shower experiment (SPASE), a joint Bartol Research Institute and Leeds University project, has been operational since the austral summer of 1987/88. It is a cosmic ray telescope searching for cosmic gamma rays at energies up to 1000 TeV. Although it has a relatively small area (6800 m2), it is situated at an altitude of 2800 m and has a 24 hour coverage, making it very competitive. The angular resolution of 0.°8 at 200 TeV is state-of-the-art in gamma ray astronomy. The astronomical programme includes searches for gamma ray sources, searches for anisotropy in the cosmic ray sky and measuring the energy spectrum over the range 1014-1016 eV.

scholarly journals What do Gamma Rays tell us about the ISM?: New Insight from the Compton Observatory

1996 ◽  
Vol 169 ◽  
pp. 437-446 ◽  
Author(s):  
Hans Bloemen
Keyword(s):  
Interstellar Medium ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Line Emission ◽  
Cosmic Ray ◽  
Gamma Ray Astronomy ◽  
Early Results ◽  
The Galaxy ◽  
Γ Ray ◽  
Insight Into

Gamma-ray astronomy has become a rich field of research and matured significantly since the launch of NASA's Compton Gamma Ray Observatory in April 1991. Studies of the diffuse γ-ray emission of the Galaxy can now be performed in far more detail and extended into the MeV regime, including both continuum and line emission. These studies provide unique insight into various aspects of the interstellar medium, in particular of the cosmic-ray component. This paper gives a brief review on the diffuse Galactic γ-ray emission and summarizes early results and prospects from the Compton Observatory.

scholarly journals Investigation of the Power of Resolution of a Spark Chamber for Gamma-Ray Astronomy

1971 ◽  
Vol 41 ◽  
pp. 73-74
Author(s):  
H. A. Mayer-Hasselwander ◽  
K. Pinkau ◽  
K. H. Schenkl ◽  
W. Voges ◽  
H. J. Schneider
Keyword(s):  
Monte Carlo ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Angular Resolution ◽  
Monte Carlo Calculation ◽  
Gamma Ray Astronomy ◽  
Calculation Technique

The registration of gamma rays in a spark chamber has been simulated by Monte-Carlo-calculation technique. The spark chamber pictures of these gamma-ray events having a known energy and direction of incidence have been analysed for determinability of direction of incidence. The values obtained for angular resolution depending on energy are compared with values derived by other authors.

Development of the Buckland Park Cosmic Ray Air Shower Array for Ultra High Energy Gamma Ray Astronomy

1986 ◽  
Vol 6 (3) ◽  
pp. 335-338 ◽  
Author(s):  
D. Ciampa ◽  
R. W. Clay ◽  
C. L. Corani ◽  
P. G. Edwards ◽  
J. R. Patterson
Keyword(s):  
Gamma Ray ◽  
Cosmic Ray ◽  
High Energy ◽  
Ultra High Energy ◽  
Gamma Ray Astronomy ◽  
Air Shower ◽  
High Energy Gamma ◽  
Energy Gamma ◽  
Shower Array ◽  
Air Shower Array

AbstractThe Buckland Park air shower array is being developed particularly for use as an ultra-high-energy gamma ray astronomy telescope. The properties of this instrument are described with an emphasis on improvements being made to its angular resolution. Some early data are presented to illustrate the way in which the data obtained will be used.

ARGO-YBJ EXPERIMENT RESULTS AND PROSPECTS IN LHAASO PROJECT

2012 ◽  
Vol 10 ◽  
pp. 147-158 ◽  
Author(s):  
◽  
MIN ZHA
Keyword(s):  
Research And Development ◽  
High Altitude ◽  
Gamma Ray ◽  
Solar Physics ◽  
Experimental Studies ◽  
Cosmic Ray ◽  
Gamma Ray Astronomy ◽  
Air Shower ◽  
Future Extension

The ARGO-YBJ detector, a RPC carpet array at the high altitude of 4300 m has been stably operated since 2007. As a multi-purpose experiment the physics topics of ARGO-YBJ covers the VHE gamma-ray astronomy, cosmic ray physics and solar physics. Results of these experimental studies are reviewed. And as a future extension project, the Large High Altitude Air Shower Observatory (LHAASO) is introduced, some research and development of detectors are described.

scholarly journals Molecular Clouds Observed by the EGRET Gamma-Ray Telescope

1997 ◽  
Vol 170 ◽  
pp. 22-24 ◽  
Author(s):  
Seth. W. Digel ◽  
Stanley D. Hunter ◽  
Reshmi Mukherjee ◽  
Eugéne J. de Geus ◽  
Isabelle A. Grenier ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Molecular Clouds ◽  
Gamma Ray ◽  
Angular Resolution ◽  
Cosmic Ray ◽  
High Energy ◽  
Background Rejection ◽  
Γ Rays ◽  
Γ Ray ◽  
Production Mechanisms

EGRET, the high-energy γ-ray telescope on the Compton Gamma-Ray Observatory, has the sensitivity, angular resolution, and background rejection necessary to study diffuse γ-ray emission from the interstellar medium (ISM). High-energy γ rays produced in cosmic-ray (CR) interactions in the ISM can be used to determine the CR density and calibrate the CO line as a tracer of molecular mass. Dominant production mechanisms for γ rays of energies ∼30 MeV–30 GeV are the decay of pions produced in collisions of CR protons with ambient matter and Bremsstrahlung scattering of CR electrons.

scholarly journals Secondary-electron radiation accompanying hadronic GeV–TeV gamma-rays from supernova remnants

2020 ◽  
Vol 492 (3) ◽  
pp. 4246-4253 ◽  
Author(s):  
Yan Huang ◽  
Zhuo Li ◽  
Wei Wang ◽  
Xiaohong Zhao
Keyword(s):  
Synchrotron Radiation ◽  
Gamma Rays ◽  
Supernova Remnants ◽  
Gamma Ray ◽  
Cosmic Ray ◽  
Far Infrared ◽  
Hadronic Interactions ◽  
Electrons And Positrons ◽  
Tev Gamma Rays ◽  
The Magnetic Field

ABSTRACT The synchrotron radiation from secondary electrons and positrons (SEPs) generated by hadronic interactions in the shock of supernova remnant (SNR) could be a distinct evidence of cosmic ray (CR) production in SNR shocks. Here, we provide a method where the observed gamma-ray flux from SNRs, created by pion decays, is directly used to derive the SEP distribution and hence the synchrotron spectrum. We apply the method to three gamma-ray bright SNRs. In the young SNR RX J1713.7−3946, if the observed GeV−TeV gamma-rays are of hadronic origin and the magnetic field in the SNR shock is B ≳ 0.5 mG, the SEPs may produce a spectral bump at 10−5–10−2 eV, exceeding the predicted synchrotron component of the leptonic model, and a soft spectral tail at ≳100 keV, distinct from the hard spectral slope in the leptonic model. In the middle-aged SNRs IC443 and W44, if the observed gamma-rays are of hadronic origin, the SEP synchrotron radiation with B ∼ 400–500 μG can well account for the observed radio flux and spectral slopes, supporting the hadronic origin of gamma-rays. Future microwave to far-infrared and hard X-ray (>100keV) observations are encouraged to constraining the SEP radiation and the gamma-ray origin in SNRs.

scholarly journals Interaction between molecular clouds and MeV–TeV cosmic-ray protons escaped from supernova remnants

2019 ◽  
Vol 71 (4) ◽  
Author(s):  
Ken Makino ◽  
Yutaka Fujita ◽  
Kumiko K Nobukawa ◽  
Hironori Matsumoto ◽  
Yutaka Ohira
Keyword(s):  
Gamma Rays ◽  
Molecular Clouds ◽  
Supernova Remnants ◽  
Gamma Ray ◽  
Cosmic Ray ◽  
Iron Line ◽  
X Ray ◽  
Line Intensities ◽  
Neutral Gas ◽  
Additional Support

Abstract Recent discovery of the X-ray neutral iron line (Fe  i Kα at 6.40 keV) around several supernova remnants (SNRs) show that MeV cosmic-ray (CR) protons are distributed around the SNRs and are interacting with neutral gas there. We propose that these MeV CRs are the ones that have been accelerated at the SNRs together with GeV–TeV CRs. In our analytical model, the MeV CRs are still confined in the SNR when the SNR collides with molecular clouds. After the collision, the MeV CRs leak into the clouds and produce the neutral iron line emissions. On the other hand, GeV–TeV CRs had already escaped from the SNRs and emitted gamma-rays through interaction with molecular clouds surrounding the SNRs. We apply this model to the SNRs W 28 and W 44 and show that it can reproduce the observations of the iron line intensities and the gamma-ray spectra. This could be additional support of the hadronic scenario for the gamma-ray emissions from these SNRs.

scholarly journals Linking supernovae and supernova remnants. Time-dependent injection in SN1987A and gamma-ray spectrum of IC443

2017 ◽  
Vol 12 (S331) ◽  
pp. 268-273
Author(s):  
O. Petruk ◽  
S. Orlando ◽  
M. Miceli
Keyword(s):  
Gamma Rays ◽  
Supernova Remnants ◽  
Gamma Ray ◽  
Supernova Explosion ◽  
Cosmic Ray ◽  
Proton Spectrum ◽  
Stationary Equation ◽  
Particle Injection ◽  
Particle Momentum ◽  
Number Of Particles

AbstractAcceleration times of particles responsible for the gamma-rays in supernova remnants (SNRs) are comparable with SNR age. If the number of particles starting acceleration was varying during early times after the supernova explosion then this variation should be reflected in the shape of the gamma-ray spectrum. In order to analyse this effect, we consider the time variation of the radio spectral index in SN1987A and solution of the non-stationary equation for particle acceleration. We reconstruct evolution of the particle injection in SN1987A, apply it to derive the particle momentum distribution in IC443 and model its gamma-ray spectrum. We show that: i) observed break in the proton spectrum around 50 GeV in IC443 is a consequence of the variation of the cosmic ray injection; ii) shape of the hadronic gamma-ray spectrum in SNRs critically depends on the temporal variation of the cosmic ray injection in the immediate post explosion phases.

Sign in / Sign up

Export Citation Format

Share Document