Azimuthal distribution for pair production by high-energy γ-rays

AbstractHESS J1731−347 a.k.a. SNR G353.6−0.7 is one of the five known very high energy (VHE, Energy > 0.1 TeV) shell-type supernova remnants. We carried out Giant Metrewave Radio Telescope (GMRT) observations of this TeV SNR in 1390, 610 and 325 MHz bands. We detected the 325 and 610 MHz radio counterparts of the SNR G353.6−0.7 (Nayana et al. 2017). We also determined the spectral indices of individual filaments and our values are consistent with the non-thermal radio emission. We compared the radio morphology with that of VHE emission. The peak in radio emission corresponds to the faintest feature in the VHE emission. We explain this anti-correlated emission in a possible leptonic origin of the VHE γ-rays.

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A CRITICAL LOOK AT PRECISION ELECTROWEAK DATA AT HIGH ENERGY—A HINT FOR PHYSICS BEYOND THE STANDARD MODEL?

Modern Physics Letters A ◽

10.1142/s0217732394003129 ◽

1994 ◽

Vol 09 (35) ◽

pp. 3301-3312

Author(s):

A. GURTU

Keyword(s):

Standard Model ◽

Pair Production ◽

High Energy ◽

Recent Measurement ◽

Beyond The Standard Model ◽

Full Data ◽

Text Production ◽

Basic Framework ◽

The Standard Model ◽

Precision Electroweak Data

High energy electroweak data, including the recent measurement of M top is analyzed within the basic framework of the standard model. While the experimentally measured value of [Formula: see text] implies a low value of M top , the rest of the data demands a much higher value. Estimates of M Higgs within the SM framework including and excluding this Rb measurement are given. Next this discrepancy is expressed in terms of a new parameter, [Formula: see text], the excess[Formula: see text] production compared to that expected from a SM fit. This parameter is determined to be (9.4 to 12.8) ± 5.0 MeV, implying an excess of over 10 000 [Formula: see text] events in each LEP experiment after the 1993 data is fully analyzed. The origin of these events could be non-minimal Higgs pair production which should be thoroughly searched for in the full data sample of ~2×106 events per LEP experiment. Unless this discrepancy eventually turns out to be a fluctuation one may be witnessing at LEP the advent of physics beyond the standard model.

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Molecular Clouds Observed by the EGRET Gamma-Ray Telescope

Symposium - International Astronomical Union ◽

10.1017/s0074180900234013 ◽

1997 ◽

Vol 170 ◽

pp. 22-24 ◽

Cited By ~ 4

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.

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