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Related papers: A microquasar model applied to unidentified gamma-…

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We propose that relativistic Galactic jets like those observed in GRS 1915+105 and GRO J1655-40 may produce small but measurable contributions to the cosmic ray (CR) spectrum. If these jets contain cold protons and heavy ions (as in SS433),…

Astrophysics · Physics 2009-11-07 S. Heinz , R. A. Sunyaev

According to radiative models, radio galaxies and quasars are predicted to produce gamma rays from the earliest stages of their evolution. Exploring their high-energy emission is crucial for providing information on the most energetic…

The physical origin of the X-ray emission in powerful quasar jets has been a long-standing mystery. Though these jets start out on the sub-pc scale as highly relativistic flows, we do not have any direct measurement of their speeds on the…

High Energy Astrophysical Phenomena · Physics 2015-03-03 Eileen T. Meyer , Markos Georganopoulos , William B. Sparks , Leith Godfrey , Eric Perlman

Giant radio sources, including galaxies and quasars (hereafter GRGs), are active galactic nuclei (AGN) hosting relativistic jets with source sizes exceeding the projected length of 0.7 Mpc. They are crucial to understanding the evolution of…

High Energy Astrophysical Phenomena · Physics 2025-07-08 Vaidehi S. Paliya , D. J. Saikia , Gabriele Bruni , Alberto Dominguez , C. S. Stalin

A prominent, 200-pc-scale high-energy nebula surrounding the microquasar V4641~Sgr is the brightest known gamma-ray source in the Southern sky at $E > 100\,\mathrm{TeV}$. In this paper, we develop self-consistent leptonic, hadronic, and…

High Energy Astrophysical Phenomena · Physics 2025-12-16 Maksim Kleimenov , Andrii Neronov , Foteini Oikonomou , Dmitri Semikoz

The diffuse gamma-ray emission from the Milky Way serves as a crucial probe for understanding the propagation and interactions of cosmic rays within our galaxy. The Galactic diffuse gamma-ray emission between 10 TeV and 1 PeV has been…

High Energy Astrophysical Phenomena · Physics 2025-01-07 Jiayin He , Houdun Zeng , Yi Zhang , Qiang Yuan , Rui Zhang , Jun Li

Microquasars, the local siblings of extragalactic quasars, are binary systems comprising a compact object and a companion star. By accreting matter from their companions, microquasars launch powerful winds and jets, influencing the…

High Energy Astrophysical Phenomena · Physics 2020-08-25 Jian Li , Diego F. Torres , Ruo-Yu Liu , Matthew Kerr , Emma de Ona Wilhelmi , Yang Su

A significant fraction (~30%) of the high-energy gamma-ray sources listed in the second Fermi LAT catalog (2FGL) are still of unknown origin, being not yet associated with counterparts at low energies. We recently developed a new…

High Energy Astrophysical Phenomena · Physics 2015-06-15 F. Massaro , R. D'Abrusco , A. Paggi , N. Masetti , M. Giroletti , G. Tosti , Howard A. Smith , S. Funk

The gamma-ray emission offers a powerful diagnostic tool to probe jets and their surroundings in flat spectrum radio quasars (FSRQ). In particular, sources emitting at high energies (>10 GeV) give us the strongest constraints. This…

High Energy Astrophysical Phenomena · Physics 2015-06-18 L. Pacciani , F. Tavecchio , I. Donnarumma , A. Stamerra , L. Carrasco , E. Recillas , A. Porras , M. Uemura

We present a study on the possible association of unidentified $\gamma$-ray sources in the Third EGRET (3EG) catalog with different types of galactic objects such as Wolf-Rayet and Of stars, supernova remnants (SNRs), and OB associations…

Astrophysics · Physics 2008-11-26 G. E. Romero , P. Benaglia , Diego F. Torres

The microquasar phenomenon is associated with the production of jets by X-ray binaries and, as such, may be associated with the majority of such systems. In this chapter we briefly outline the associations, definite, probable, possible, and…

Astrophysics · Physics 2015-06-24 Rob Fender , Tom Maccarone

The recently detected extended, very-high-energy gamma-ray emission from the microquasar V4641 Sgr reveals a puzzling 200-parsec-long jet-like structure significantly misaligned with its radio jet. We propose that this gamma-ray structure…

High Energy Astrophysical Phenomena · Physics 2024-10-24 Andrii Neronov , Foteini Oikonomou , Dmitri Semikoz

4FGL J1405.1-6119 is a high-mass $\gamma$-ray emitting binary that has been studied at several wavelengths. The nature of this type of binary is still under debate, with three possible scenarios usually invoked to explain the origin of the…

High Energy Astrophysical Phenomena · Physics 2023-12-20 Enzo A. Saavedra , Federico A. Fogantini , Gastón J. Escobar , Gustavo E. Romero , Jorge A. Combi , Estefania Marcel

According to radiative models, radio galaxies are predicted to produce gamma rays from the earliest stages of their evolution onwards.The study of the high-energy emission from young radio sources is crucial for providing information on the…

High Energy Astrophysical Phenomena · Physics 2021-09-23 Giacomo Principe , Leonardo Di Venere , Giulia Migliori , Monica Orienti , Filippo D'Ammando

According to radiative models, radio galaxies are predicted to produce gamma-rays from the earliest stages of their evolution onwards. The study of the high-energy emission from young radio sources is crucial for providing information on…

High Energy Astrophysical Phenomena · Physics 2022-01-05 Giacomo Principe , Leonardo Di Venere , Giulia Migliori , Monica Orienti , Filippo D'Ammando

We propose that some of the high-latitude unidentified EGRET gamma-ray sources could be the result of gravitational lensing amplification of the innermost regions of distant, faint, active galactic nuclei. These objects have gamma-ray…

Astrophysics · Physics 2009-11-07 Diego F. Torres , Gustavo E. Romero , Ernesto F. Eiroa

Statistical studies indicate that the 271 point sources of high-energy gamma rays belong to two groups: a Galactic population and an isotropic extragalactic population. Many unidentified extragalactic sources are certainly blazars, and it…

Astrophysics · Physics 2009-11-10 P. M. Wallace , S. D. Bloom , M. S. Lewis

In this work, after making an attempt to improve the formulation of the model on particle transport within astrophysical plasma outflows and constructing the appropriate algorithms, we test the reliability and effectiveness of our method…

High Energy Astrophysical Phenomena · Physics 2021-12-30 D. A. Papadopoulos , O. T. Kosmas , S. Ganatsios

B2013+370 and B2023+336 are two blazars at low-galactic latitude that were previously proposed to be the counterparts for the EGRET unidentified sources, 3EG J2016+3657 and 3EG J2027+3429. Gamma-ray emission associated with the EGRET…

High Energy Astrophysical Phenomena · Physics 2015-06-03 E. Kara , M. Errando , W. Max-Moerbeck , E. Aliu , M. Bottcher , P. Fortin , J. P. Halpern , R. Mukherjee , A. C. S. Readhead , J. L. Richards

We present a model for high-energy emission in microquasars where the energy content of the jets is dominated by relativistic protons. We also include a primary leptonic component. Particles are accelerated up to relativistic energies in a…

Astrophysics · Physics 2009-11-13 Gabriela S. Vila , Gustavo E. Romero
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