中文
相关论文

相关论文: A pair plasma model for PKS 0208-512

200 篇论文

A vector-dominance two-photon exchange model is proposed to explain the recently observed production of $\rho^0\rho^0$ and $\rho^0\phi$ pairs in $e^+e^-$ annihilation at 10.58 GeV with the BaBar detector. All the observed features of the…

高能物理 - 唯象学 · 物理学 2007-05-23 M. Davier , M. Peskin , A. Snyder

Jets produced in high energy heavy ion collisions are quenched by the quark gluon plasma. Measurements of these jets are influenced by the methods used to suppress and subtract the large, fluctuating background and the assumptions inherent…

高能物理 - 唯象学 · 物理学 2022-11-03 Charles Hughes , Antonio Carlos Oliveira Da Silva , Christine Nattrass

Recent observations of the polarisation of the optical pulses from the Crab pulsar motivated detailed comparative studies of the emission predicted by the polar cap, the outer gap and the two-pole caustics models. In this work, we study the…

天体物理学 · 物理学 2008-11-26 J. Petri , J. Kirk

We discuss gamma-ray signatures associated with an asymmetric explosion and transport of positrons in SN Ia ejecta. In particular, Compton scattering of gamma-ray line photons can induce polarization in the continuum, which would be a…

高能天体物理现象 · 物理学 2018-08-01 Eugene Churazov , Ildar Khabibullin

The current cosmological structure formation models predict that galaxies evolve through frequent mergers. During these events, the supermassive black holes (SMBHs) residing in the centres of the galaxies shrink to the central region, while…

星系天体物理 · 物理学 2022-03-10 Krisztina É. Gabányi , Sándor Frey , Emma Kun , Zsolt Paragi , Tao An

Astrophysical models for the high-energy emission of blazars are reviewed. Blazars ejecting relativistic radio jets at small angles to the line-of-sight are the only type of active galactic nuclei (AGN) discovered above 100 MeV. The…

天体物理学 · 物理学 2007-05-23 Karl Mannheim

We introduce a simple and convenient fitting formula for the thermal annihilation line from pair plasmas in cosmic sources. The fitting formula is accurate to 0.04\% and is valid at all photon energies and temperatures of interest. The…

天体物理学 · 物理学 2007-05-23 Roland Svensson , Stefan Larsson , Juri Poutanen

The origin of intergalactic magnetic fields (IGMFs) remains one of the key open questions in cosmology. Gamma-ray pair halos produced by electromagnetic cascades from TeV-emitting blazars provide a powerful indirect probe of these fields.…

高能天体物理现象 · 物理学 2026-04-30 Ao Zhang , Wenlei Chen , Manel Errando

Electron-positron pair creation in a standing wave is explored using a parameter-free quantum kinetic equation. Field strengths and frequencies corresponding to modern optical lasers induce a material polarisation of the QED vacuum, which…

We consider stochastic particle acceleration in plasmas around stellar mass black holes to explain the emissions above 1 MeV from Galactic black hole candidates. We show that for certain parameter regimes, electrons can overcome Coulomb…

天体物理学 · 物理学 2009-10-28 Hui Li , Masaaki Kusunose , Edison Liang

In a new divertor simulator, an ultra-cold (Te<1 eV) high density recombining magnetized laboratory plasma is studied using probes, spectroscopic measurements, and ultra-fast imaging of spontaneous emission. The Mistral-B device consists in…

It is shown that a Weakly Interacting Massive dark matter Particle (WIMP) interpretation for the positron excess observed in a variety of experiments, HEAT, PAMELA, and AMS-02, is highly constrained by the Fermi/LAT observations of dwarf…

宇宙学与河外天体物理 · 物理学 2016-04-06 Alejandro Lopez , Christopher Savage , Douglas Spolyar , Douglas Q. Adams

The cosmic-ray flux of positrons is measured with high precision by the space-borne particle spectrometer AMS-02. The hypothesis that pulsar wind nebulae (PWNe) can significantly contribute to the excess of the positron ($e^+$) cosmic-ray…

高能天体物理现象 · 物理学 2021-12-08 Luca Orusa , Silvia Manconi , Fiorenza Donato , Mattia Di Mauro

We present the results of lifetime positron annihilation spectroscopy (PALS) for the alloys Fe21Ga and Fe22.4Ga, whose defect structure is connected with annealing from 20 to 1000C along the phase diagram of Fe21Ga and Fe22.4Ga, at the…

材料科学 · 物理学 2015-09-08 L. V. El'nikova , Yu. V. Funtikov

The cosmic electron energy spectrum recently observed by the DAMPE experiment exhibits two interesting features, including a break around 0.9 TeV and a sharp resonance near 1.4 TeV. In this analysis, we propose a dark matter explanation to…

高能物理 - 唯象学 · 物理学 2022-10-12 Xuewen Liu , Zuowei Liu , Yushan Su

Axion-Like Particles (ALPs), if exist in nature, are expected to mix with photons in the presence of an external magnetic field. The energy range of photons which undergo strong mixing with ALPs depends on the ALP mass, on its coupling with…

高能天体物理现象 · 物理学 2013-11-13 Olga Mena , Soebur Razzaque

To investigate parsec-scale jet flow conditions during GeV gamma-ray flares detected by the Fermi Large Angle Telescope, we obtained centimeter-band total flux density and linear polarization monitoring observations from 2009.5 through…

高能天体物理现象 · 物理学 2015-06-22 M. F. Aller , P. A. Hughes , H. D. Aller , G. E. Latimer , T. Hovatta

We consider the singlet scalar model of dark matter and study the expected antiproton and positron signals from dark matter annihilations. The regions of the viable parameter space of the model that are excluded by present data are…

高能物理 - 唯象学 · 物理学 2009-12-15 A. Goudelis , Y. Mambrini , C. Yaguna

An interesting paper has recently been published claiming that the long-sought Rosetta Stone needed to decipher the nature of pulsar radio emission has been finally identified as the double features in averaged pulsar profiles. The authors…

太阳与恒星天体物理 · 物理学 2010-05-06 Janusz A. Gil , George I. Melikidze

The highly variable and energetic pulsed emission of a long gamma-ray burst (GRB) is thought to originate from local, rapid dissipation of kinetic or magnetic energy within an ultra-relativistic jet launched by a newborn compact object,…