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Related papers: Angular Correlations of the MeV Cosmic Gamma Ray B…

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The nuclear $\gamma$-ray lines in the MeV range of the electromagnetic spectrum hold a vast variety of astrophysical, particle-physical, and fundamental physical information that is otherwise extreme difficult to access. MeV $\gamma$-ray…

High Energy Astrophysical Phenomena · Physics 2026-02-05 Thomas Siegert , Francesca Calore , Pierre Jean , Mark Leising , Nicolas de Séréville , Gerald H. Share , Vincent Tatischeff , Wei Wang , Meng-Ru Wu

Probing the evolution of the universe at high redshifts with standard candles is a powerful way to discriminate dark energy models, where an open question nowadays is whether this component is constant or evolves with time. One possible…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , V. C. Busti

We present a new method for time-efficient and accurate extraction of the power spectrum from future cosmic microwave background (CMB) maps based on properties of peaks and troughs of the Gaussian CMB sky. We construct a statistic…

Astrophysics · Physics 2009-11-06 A. Kashlinsky , C. Hernández--Monteagudo , F. Atrio--Barandela

The LambdaCDM model is the most commonly accepted framework in modern cosmology. However, the local measurements of the Hubble constant, H0, via the Supernovae Type Ia (SNe Ia) calibrated on Cepheids provide a value which is in significant…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-28 M. G. Dainotti , B. De Simone , G. Montani , E. Rinaldi , M. Bogdan , K. M. Islam , A. Gangopadhyay

We provide our estimates of the intensity of the gamma-ray emission with an energy near 0.1 TeV generated in inrergalactic space in the interactions of cosmic rays with background emissions. We assume that the cosmic ray sources are…

High Energy Astrophysical Phenomena · Physics 2017-08-30 A. V. Uryson

Observations of the Cosmic Microwave Background (CMB), large scale structure (LSS) and standard candles such as Type 1a Supernovae (SN) each place different constraints on the values of cosmological parameters. We assume an inflationary…

Astrophysics · Physics 2007-05-23 A. N. Lasenby , S. L. Bridle , M. P. Hobson

There is growing evidence that long and hard gamma-ray bursts (GRBs), discovered at redshifts between 0.4 and 3.4, are related to some type of supernova (SN) explosions. The GRB ejecta are ultra-relativistic, and possibly beamed. There is a…

Astrophysics · Physics 2007-05-23 Bohdan Paczynski

The optical light curve of Type Ia supernovae (SNIa) is powered by thermalized gamma-rays produced by the decay of 56Ni and 56Co, the main radioactive isotopes synthesized by the thermonuclear explosion of a C/O white dwarf. Gamma-rays…

Despite the ability of the cosmological concordance model ($\Lambda$CDM) to describe the cosmological observations exceedingly well, power law expansion of the Universe scale radius, $R(t)\propto t^n$, has been proposed as an alternative…

Recent re-calibration of the Type Ia supernova (SNe~Ia) magnitude-redshift relation combined with cosmic microwave background (CMB) and baryon acoustic oscillation (BAO) data have provided excellent constraints on the standard cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-02 Suhail Dhawan , Ariel Goobar , Edvard Mörtsell , Rahman Amanullah , Ulrich Feindt

Type 1a supernova magnitudes are used to fit cosmological parameters under the assumption the model will fit the observed redshift dependence. We test this assumption with the Union 2.1 compilation of 580 sources. Several independent tests…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-26 Gopolang M. Mohlabeng , John P. Ralston

An important concern in the application of gamma-ray bursts (GRBs) to cosmology is that the calibration of GRB luminosity/energy relations depends on the cosmological model, due to the lack of a sufficient low-redshift GRB sample. In this…

Astrophysics · Physics 2009-11-13 Nan Liang , Wei Ke Xiao , Yuan Liu , Shuang Nan Zhang

The origin of the extragalactic gamma-ray background is a pressing cosmological mystery. The Fermi Gamma-Ray Space Telescope has recently measured the intensity and spectrum of this background; both are substantially different from previous…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-16 Brian D. Fields , Vasiliki Pavlidou , Tijana Prodanovic

In this paper we study cosmological signatures of modified gravity theories that can be written as a coupling between a extra scalar field and the electromagnetic part of the usual Lagrangian for the matter fields. In these frameworks all…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , S. H. Pereira

We cross correlate the large-scale cosmic microwave background (CMB) sky measured by WMAP with two probes of large-scale structure at z ~ 1. The hard X-ray background, measured by the HEAO-1 satellite, is positively correlated with the WMAP…

Astrophysics · Physics 2008-11-26 Stephen Boughn , Robert Crittenden

The COMPTEL and EGRET detectors aboard the Compton Gamma-Ray Observatory measured an extragalactic gamma-ray background extending from MeV energies up to about 100 GeV. Calculations performed making reasonable assumptions indicate that…

Astrophysics · Physics 2009-11-06 F. W. Stecker , M. H. Salamon

Integrated X-ray spectra of an evolving population of starburst galaxies (SBGs) are determined based on the observed spectra of local SBGs. In addition to emission from hot gas and binary systems, our model SBG spectrum includes a…

Astrophysics · Physics 2009-11-07 M. Persic , Y. Rephaeli

The intrinsic peak luminosity of Type Ia supernovae (SNIa) depends on the value of Newton's gravitational constant $G$, through the Chandrasekhar mass $M_{\rm Ch}\propto G^{-3/2}$. If the luminosity distance can be independently determined,…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-31 Wen Zhao , Bill S. Wright , Baojiu Li

We use the new results of the HEGRA detector on the TeV gamma-ray emission from MKN 501 to set upper limits on the energy density of the cosmic infrared background (CIRB). Contrary to previous interpretations of the gamma-ray spectrum of…

Astrophysics · Physics 2010-11-30 Todor Stanev , Alberto Franceschini

We study how future Type-Ia supernovae (SNIa) standard candles detected by the Vera C. Rubin Observatory (LSST) can constrain some cosmological models. We use a realistic three-year SNIa simulated dataset generated by the LSST Dark Energy…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-25 Rahul Shah , Ayan Mitra , Purba Mukherjee , Barun Pal , Supratik Pal
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