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Related papers: On Thermal Comptonization in e+- Pair Plasmas

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We review a physical model where the high brightness temperature of 10$^{25}-10^{30}$ K observed in pulsar radio emission is explained by coherent curvature radiation excited in the relativistic electron-positron plasma in the pulsar…

High Energy Astrophysical Phenomena · Physics 2015-10-02 Dipanjan Mitra , G. Melikidze , Janusz Gil

Temperature dependence of an electron-nuclear plasma equilibrium density is considered basing on known approaches, which are given in (1)(2). It is shown that at a very high temperature, which is characteristic for a star interior, the…

Astrophysics · Physics 2010-11-11 B. V. Vasiliev

We have found relations between the temporal and spectral properties of radiation Comptonized in an extended atmosphere associated with compact accreting sources. We demonstrate that the fluctuation power spectrum density (PSD) imposes…

Astrophysics · Physics 2007-05-23 Demos Kazanas , Xin-Min Hua , Lev Titarchuk

Fluctuations in the initial QCD matter density distribution are found to enhance the production of thermal photons significantly in the range 2 \leq pT \leq 4 GeV/c compared to a smooth initial state averaged profile in ideal hydrodynamic…

Nuclear Theory · Physics 2015-06-04 Rupa Chatterjee , Hannu Holopainen , Thorsten Renk , Kari J. Eskola

Explicit expressions for the differential and total rates and emissivities of neutrino pairs from the photo-neutrino process $e^\pm + \gamma \to e^\pm + \nu + \bar\nu$ in hot and dense matter are derived. Full information about the emitted…

Astrophysics · Physics 2009-11-10 Sharada Iyer Dutta , Sasa Ratkovic , Madappa Prakash

In this study, the theoretical maximum efficiency $\eta_{max}$ and the Boltzmann-type factor giving the concentration ratio of excited-to-ground state pigment-molecules for photosynthetic systems under irradiation with arbitrary photon flux…

Statistical Mechanics · Physics 2025-12-17 Tetsuo Yabuki

We have observed momentum- and position-resolved spectra and images of the photoluminescence from thermalised and condensed dye-microcavity photons. The spectra yield the dispersion relation and the potential energy landscape for the…

Quantum Gases · Physics 2016-12-15 Jakov Marelic , Benjamin T. Walker , Robert A. Nyman

Modelling the emission properties of compact high energy sources such as X-ray binaries, AGN or gamma-ray bursts represents a complex problem. Contributions of numerous processes participate non linearly to produce the observed spectra:…

Astrophysics · Physics 2009-11-13 R. Belmont , J. Malzac , A. Marcowith

We determine X-ray temperatures and abundances for elliptical galaxies drawn from a complete, optically selected sample. The optical magnitude-limited sample consists of 43 galaxies, complete to a (corrected) B magnitude of m_B^o=11.36. Of…

Astrophysics · Physics 2015-06-24 David S. Davis , Raymond E. White

The Compton Gamma Ray Observatory revealed the high energy emission of some Active Galactic Nuclei called "Blazars"; few of them have also been observed by ground Cererenkov arrays. Those sources observed with Whipple Observatory emit gamma…

Astrophysics · Physics 2007-05-23 G. Pelletier , G. Henri

Solar flares produce hard X-ray emission of which the photon spectrum is often represented by a combination of thermal and power-law distributions. However, the estimates of the number and total energy of non-thermal electrons are sensitive…

Solar and Stellar Astrophysics · Physics 2015-06-12 M. Oka , S. Ishikawa , P. Saint-Hilaire , S. Krucker , R. P. Lin

We solve for the structure of a hot accretion disc with unsaturated thermal Comptonisation of soft photons and with advection, generalizing the classical model of Shapiro et al. The upper limit on the accretion rate due to advection…

Astrophysics · Physics 2015-06-24 Andrzej A. Zdziarski

Nonlinear Compton scattering driven by ultraintense lasers presents a promising avenue for enhancing the photon energy, brilliance, and setup compactness of $\gamma$-ray sources. However, a significant challenge lies in achieving a high…

Plasma Physics · Physics 2024-04-12 Xian-Zhang Wu , Yan-Fei Li , Yu-Tong Li

Electromagnetic radiation at higher harmonics of the plasma frequency ($\omega \sim n\omega_{pe}, n > 2$) has been occasionally observed in type II and type III solar radio bursts, yet the underlying mechanism remains undetermined. Here we…

Solar and Stellar Astrophysics · Physics 2023-12-22 Chuanyang Li , Yao Chen , Zilong Zhang , Hao Ning , TangMu Li

Based on the quantum electrodynamics, we present a generic formalism of the polarization for beamed monochromatic photons scattered by electrons in any spectral distribution. The formulae reduce to the components of the Fano matrix when…

High Energy Astrophysical Phenomena · Physics 2014-11-07 Zhe Chang , Yunguo Jiang , Hai-Nan Lin

We self-consistently estimate the outflow rate from the accretion rates of an accretion disk around a black hole in which both the Keplerian and the sub-Keplerian matter flows simultaneously. While Keplerian matter supplies soft-photons,…

Astrophysics · Physics 2009-11-10 Santabrata Das , Indranil Chattopadhyay , A. Nandi , Sandip K. Chakrabarti

Thermal photons can provide information on the temperature of the new state of matter created at RHIC. In the p_T region of 1--3 GeV/c thermal photons are expected to be the dominant direct photon source. Therefore, a possible excess…

Nuclear Experiment · Physics 2019-08-14 Torsten Dahms

We report results from a series of PIC simulations carried out to investigate the interaction of intense laser light with overdense plasma and in particular, aspects of the harmonic emission spectrum generated in these interactions. Recent…

Plasma Physics · Physics 2007-05-23 Tim James Morrow Boyd , Ricardo Ondarza-Rovira

Solar flare electron acceleration is an efficient process, but its properties (mechanism, location) are not well constrained. Via hard X-ray (HXR) emission, we routinely observe energetic electrons at the Sun, and sometimes we detect…

Solar and Stellar Astrophysics · Physics 2023-10-09 Ross Pallister , Natasha L. S. Jeffrey

In this manuscript, a fluid model is utilized to calculate the density of plasma species assuming geometrically symmetric Ar/CF4 Radiofrequency Capacitively Coupled Plasmas. The electrodes are driven by a sinusoidal waefront with an…

Plasma Physics · Physics 2023-03-28 M. G. Elsheikh , Y. Abdella , T. El-Ashram , W. M. Moslem , M. Shihab
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