scholarly journals Cosmic Rays and the Dynamic Balance in the Large Magellanic Cloud

1990 ◽  
Vol 123 ◽  
pp. 537-541
Author(s):  
Carl E. Fichtel ◽  
Mehmet E. Ozel ◽  
Robert G. Stone

AbstractPresent and future measurement of the Large Magellanic Cloud (LMC) particularly in the radio and high energy gamma ray range offer the possibility of understanding the density and distribution of the cosmic rays in a galaxy other than our own and the role that they play in galactic dynamic balance. After a study of the consistency of the measurements and interpretation of the synchrotron radiation from our own galaxy, the cosmic ray distribution for the LMC is calculated under the assumption that the cosmic ray nucleon to electron ratio is the same and the relation to the magnetic fields are the same, although the implications of alternatives are discussed. It is seen that the cosmic ray density level appears to be similar to that in our own galaxy, but varying in position in a manner generally consistent with the concept of correlation with the matter on a broad scale.

2018 ◽  
Vol 191 ◽  
pp. 01007 ◽  
Author(s):  
N. Budnev ◽  
I. Astapov ◽  
P. Bezyazeekov ◽  
V. Boreyko ◽  
A. Borodin ◽  
...  

The physics motivations and advantages of the new TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) detector are presented. TAIGA aims at gamma-ray astronomy at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV. For the energy range 30 – 200 TeV the sensitivity of 10 km2 area TAIGA array for the detection of local sources is expected to be 5 × 10-14 erg cm-2 sec-1 for 300 h of observations. Reconstruction of the given EAS energy, incoming direction and its core position, based on the timing TAIGA-HiSCORE data, allows one to increase a distance between the IACTs up to 600-1000 m. The low investments together with the high sensitivity for energies ≥ 30-50 TeV make this pioneering technique very attractive for exploring the galactic PeVatrons and cosmic rays. At present the TAIGA first stage has been constructed in Tunka valley, 50 km West from the Lake Baikal. The first experimental results of the TAIGA first stage are presented.


1985 ◽  
Vol 106 ◽  
pp. 213-218
Author(s):  
W. Hermsen ◽  
J.B.G.M. Bloemen

The COS-B gamma-ray survey is compared with 12CO and HI surveys in a region containing the Orion complex and in the outer Galaxy. The observed gamma-ray intensities in the Orion region (100 MeV<E<5 GeV) can be ascribed to the interaction of uniformly distributed cosmic rays with the interstellar gas. Calibration of the ratio between H2 column-density and integrated CO line intensity resulted in the value: (3.0±0.7)x102 0 molecules cm-2K -1km -1s. In the outer Galaxy HI column-density maps in three galacto-centric distance ranges are used in combination with COS-B gamma-ray data to determine the radial distribution of the gamma-ray emissivity. A steep negative gradient of the emissivity for the 70 MeV-150 MeV range and an approximately constant (within ~20%) emissivity for the 300 MeV-5 GeV range is found. The result is interpreted as a strong decrease in the cosmic-ray electron density and a near constancy of the nuclear component.


2019 ◽  
Vol 209 ◽  
pp. 01021
Author(s):  
María Isabel Bernardos ◽  
María Benito ◽  
Fabio Iocco ◽  
Salvatore Mangano ◽  
Olga Sergijenko ◽  
...  

The Large Magellanic Cloud (LMC) is a spiral galaxy, satellite of the Milky way with a high star formation activity. It represents a unique laboratory for studying an extended and spatially resolved star-forming galaxy through gamma-ray observatories. Therefore, the LMC survey is one of the key science projects for the Cherenkov Telescope Array (CTA), the next-generation ground-based gamma-ray observatory. In this document we present the work performed over the last year by the CTA working group dedicated to the LMC, in order to offer a first characterization of the LMC at TeV energies. We have performed detectability forecasts based on the expected CTA performance for all sources in the region of interest of the LMC with known emission at GeV energies and above. Based on previous observations made by Fermi-LAT and H.E.S.S. we have characterized all point sources, extended sources and diffuse emission produced by cosmic-ray propagation, extrapolating their spectra to CTA energies. Finally, we have characterized the signal expected by different annihilation mechanisms of dark matter (DM) particles within the LMC, computing the detection sensitivity curve for this target in the cross-section-to-mass plane.


2003 ◽  
Vol 214 ◽  
pp. 382-386
Author(s):  
Masato Takita

Sub-TeV and TeV energy gamma-ray astronomy reveals non-thermal gamma-ray pictures of our universe and serve as a probe to understand the origin, acceleration and propagation of cosmic rays. Recent status of ground-based high-energy gamma-ray astronomy is reviewed.


1986 ◽  
Vol 6 (3) ◽  
pp. 335-338 ◽  
Author(s):  
D. Ciampa ◽  
R. W. Clay ◽  
C. L. Corani ◽  
P. G. Edwards ◽  
J. R. Patterson

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.


1992 ◽  
Vol 400 ◽  
pp. L67 ◽  
Author(s):  
P. Sreekumar ◽  
D. L. Bertsch ◽  
B. L. Dingus ◽  
C. E. Fichtel ◽  
R. C. Hartman ◽  
...  

2021 ◽  
Author(s):  
A. Ivanova ◽  
R. Monkhoev ◽  
I. Astapov ◽  
P. Bezyazeekov ◽  
A. Borodin ◽  
...  

1996 ◽  
Vol 168 ◽  
pp. 279-288
Author(s):  
P. Sreekumar ◽  
D.A. Kniffen

The all-sky survey in high energy gamma rays (E&gt;30 MeV) carried out by the Energetic Gamma Ray Experiment Telescope (EGRET) aboard the Compton Gamma Ray Observatory provides for the first time an opportunity to examine in detail diffuse gamma-ray emission of extra-galactic origin. The observed diffuse emission at high galactic latitudes is generally assumed to have a galactic component arising from cosmic-ray interactions with the local interstellar gas and radiation, in addition to an isotropic component presumably of extragalactic origin. The galactic component can be estimated from a model of the interstellar medium and cosmic-ray distribution. Since the derived extragalactic spectrum depends very much on the success of our galactic model, the consistency of the galactic diffuse emission model is examined both spectrally and spatially with existing EGRET observations. In conjunction with this model, EGRET observations of the high latitude emission are used to examine the flux and spectrum of the residual extragalactic emission. This residual emission could be either truly diffuse in origin or could arise from accumulated emission from unresolved sources particularly in the light of EGRET observations showing the presence of numerous gamma-ray bright active galactic nuclei.


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