Non-thermal bremsstrahlung from supernova remnants and the effect of Coulomb losses

Abstract

I investigate the shape of the electron cosmic ray spectrum in the range up to ~1000 keV, assuming that the acceleration process at the shock results in a power law in momentum, and that downstream of the shock the spectrum is affected by Coulomb interactions with background electrons only. In the non-relativistic regime one can analytically determine the energy of an electron starting with a certain energy, and use this result to produce an electron cosmic ray spectrum, modified by Coulomb losses. An analytic expression for the electron spectrum is obtained that depends on the parameter n_e t, which can be estimated from a similar parameter used to characterize the line spectra of supernova remnants. For the brightest supernova remnants n_e t > 1e11 cm^-3 s,and most of the electrons accelerated to < 100 keV have lost their energy. Because of its high radio flux, Cas A is the most likely candidate for non-thermal bremsstrahlung. Although it has n_e t ~ 2e11 cm^-3 s, one may expect to pick up non-thermal bremsstrahlung above 100 keV with current hard X-ray detectors.

arXiv commentTo be published as a research note in A & A

References in corpus (25)

• Hard X-ray Detector (HXD) on Board Suzaku
• High-energy particle acceleration in the shell of a supernova remnant
• On the magnetic fields and particle acceleration in Cas A
• Magnetic Field Amplification in Tycho and other Shell-type Supernova Remnants
• The Energy Spectrum of Primary Cosmic Ray Electrons in Clusters of Galaxies and Inverse Compton Emission
• Cosmic Ray Acceleration at the Forward Shock in Tycho's Supernova Remnant: Evidence from Chandra X-ray Observations
• A Spatial and Spectral Study of Nonthermal Filaments in Historical Supernova Remnants: Observational Results with Chandra
• Observational constraints on energetic particle diffusion in young SNRs: amplified magnetic field and maximum energy
• A Physical Relationship Between Electron-Proton Temperature Equilibration and Mach Number in Fast Collisionless Shocks
• Detection of TeV gamma-ray Emission from the Shell-Type Supernova Remnant RX J0852.0-4622 with H.E.S.S
• Evidence of X-ray Synchrotron Emission from Electrons Accelerated to 40 TeV in the Supernova Remnant Cassiopeia A
• X-ray spectral imaging and Doppler mapping of Cassiopeia A
• Confirmation of strong magnetic field amplification and nuclear cosmic ray acceleration in SN 1006
• The signature of 44Ti in Cassiopeia A revealed by IBIS/ISGRI on INTEGRAL
• The X-ray synchrotron emission of RCW 86 and the implications for its age
• Detection of the 67.9 keV and 78.4 keV lines associated with the radioactive decay of Ti-44 in Cassiopeia A
• Slow Temperature Equilibration Behind the Shock Front of SN 1006
• Direct evidence of efficient cosmic ray acceleration and magnetic field amplification in Cassiopeia A
• Observation of VHE gamma-rays from Cassiopeia A with the MAGIC telescope
• Hydrodynamic Simulation of Supernova Remnants Including Efficient Particle Acceleration
• Nonlinear Particle Acceleration at Reverse Shocks in Supernova Remnants
• Accelerated Electrons in Cassiopeia A: An Explanation for the Hard X-ray Tail
• Cosmic ray diffusion near the Bohm limit in the Cassiopeia A supernova remnant
• Accelerated Electrons in Cassiopeia A: Thermal and Electromagnetic Effects
• X-Ray Observations of SN 1006 with Integral

Cited by in corpus (19)

• Supernova remnants: the X-ray perspective
• Observational signatures of particle acceleration in supernova remnants
• Characterizing the non-thermal emission of Cas A
• Locating the most energetic electrons in Cassiopeia A
• Suzaku X-Ray Imaging and Spectroscopy of Cassiopeia A
• Non-Thermal X-ray Emission from the Northwestern Rim of the Galactic Supernova Remnant G266.2-1.2 (RX J0852.0-4622)
• The Hard X-Ray View of the Young Supernova Remnant G1.9+0.3
• Synchrotron X-ray diagnostics of cutoff shape of nonthermal electron spectrum at young supernova remnants
• NuSTAR Detection of a Hard X-ray Source in the Supernova Remnant - Molecular Cloud Interaction Site of IC 443
• Searching for the inverse-Compton emission from bright cluster-centre radio galaxies
• Suppression of Bremsstrahlung losses from relativistic plasma with energy cutoff
• Suzaku observations of the hard X-ray spectrum of Vela Jr
• LMC N132D: A mature supernova remnant with a power-law gamma-ray spectrum extending beyond 8 TeV
• An XMM-Newton Study of the Mixed-Morphology Supernova Remnant G346.6-0.2
• Evidence for thermal X-ray emission from the synchrotron dominated shocks in Tycho's supernova remnant
• The auto and cross angular power spectrum of the Cas A supernova remnant in radio and X-ray
• Relativistic Non-Thermal Bremsstrahlung Radiation
• Nonthermal processes and particle acceleration in supernova remnants
• The forward and reverse shock dynamics of Cassiopeia A