Constraining the coherence scale of the interstellar magnetic field using TeV gamma-ray observations of supernova remnants

Abstract

Galactic cosmic rays (CRs) are believed to be accelerated at supernova remnant (SNR) shocks. In the hadronic scenario the TeV gamma-ray emission from SNRs originates from decaying pions that are produced in collisions of the interstellar gas and CRs. Using CR-magnetohydrodynamic simulations, we show that magnetic obliquity-dependent shock acceleration is able to reproduce the observed TeV gamma-ray morphology of SNRs such as Vela Jr. and SN1006 solely by varying the magnetic morphology. This implies that gamma-ray bright regions result from quasi-parallel shocks (i.e., when the shock propagates at a narrow angle to the upstream magnetic field), which are known to efficiently accelerate CR protons, and that gamma-ray dark regions point to quasi-perpendicular shock configurations. Comparison of the simulated gamma-ray morphology to observations allows us to constrain the magnetic coherence scale ${\lambda }_B$ around Vela Jr. and SN1006 to ${\lambda }_B\simeq 13_{-4.3}^{+13}$ pc and ${\lambda }_B>200_{-10}^{+80}$ pc, respectively, where the ambient magnetic field of SN1006 is consistent with being largely homogeneous. We find consistent pure hadronic and mixed hadronic-leptonic models that both reproduce the multi-frequency spectra from the radio to TeV gamma rays and match the observed gamma-ray morphology. Finally, to capture the propagation of a SNR shock in a clumpy interstellar medium, we study the interaction of a shock with a dense cloud with numerical simulations and analytics. We construct an analytical gamma-ray model for a core collapse SNR propagating through a structured interstellar medium, and show that the gamma-ray luminosity is only biased by 30% for realistic parameters.

arXiv comment16 pages, 9 figures

References in corpus (60)

• E pur si muove: Galiliean-invariant cosmological hydrodynamical simulations on a moving mesh
• Fermi Large Area Telescope First Source Catalog
• Energy spectra of gamma-rays, electrons and neutrinos produced at proton-proton interactions in the very high energy regime
• Detection of the Characteristic Pion-Decay Signature in Supernova Remnants
• Simulations of Ion Acceleration at Non-relativistic Shocks. I. Acceleration Efficiency
• Improving the convergence properties of the moving-mesh code AREPO
• Simulations of magnetic fields in isolated disk galaxies
• A detailed spectral and morphological study of the gamma-ray supernova remnant RX J1713.7-3946 with H.E.S.S
• Teraelectronvolt Astronomy
• The growth and entrainment of cold gas in a hot wind
• Constraining the population of cosmic ray protons in cooling flow clusters with gamma-ray and radio observations: Are radio mini-halos of hadronic origin?
• Strong evidences of hadron acceleration in Tycho's Supernova Remnant
• A Characteristic Scale for Cold Gas
• Toward Understanding the Cosmic-ray Acceleration at Young Supernova Remnants Interacting with Interstellar Clouds: Possible Applications to RX J1713.7-3946
• RXJ 0852.0-0462: Another Nonthermal Shell-Type SNR (G266.2-1.2)
• H.E.S.S. observations of the supernova remnant RX J0852.0-4622: shell-type morphology and spectrum of a widely extended VHE gamma-ray source
• Simulating cosmic ray physics on a moving mesh
• The 2010 very high energy gamma-ray flare & 10 years of multi-wavelength observations of M 87
• HESS Observations and VLT Spectroscopy of PG 1553+113
• The SN 1006 Remnant: Optical Proper Motions, Deep Imaging, Distance, and Brightness at Maximum
• Nonthermal Radiation of Young Supernova Remnants
• First detection of VHE gamma-rays from SN 1006 by H.E.S.S
• Simulating cosmic rays in clusters of galaxies - II. A unified scheme for radio halos and relics with predictions of the gamma-ray emission
• The Evolution of Supernovae in Circumstellar Wind-Blown Bubbles I. Introduction and One-Dimensional Calculations
• Instabilities and Clumping in Type Ia Supernova Remnants
• On the Radio Polarization Signature of Efficient and Inefficient Particle Acceleration in Supernova Remnant SN 1006
• H.E.S.S. observations of RX J1713.7-3946 with improved angular and spectral resolution; evidence for gamma-ray emission extending beyond the X-ray emitting shell
• Gamma-Ray Observations of the Supernova Remnant RX J0852.0-4622 with the Fermi LAT
• Hadronic gamma-rays from RX J1713.7-3946?
• The physics of multiphase gas flows: fragmentation of a radiatively cooling gas cloud in a hot wind
• On the Expansion Rate, Age, and Distance of the Supernova Remnant G266.2-1.2 (Vela Jr.)
• The Slow X-Ray Expansion of the Northwestern Rim of the Supernova Remnant RX J0852.0-4622
• Shock finding on a moving-mesh: I. Shock statistics in non-radiative cosmological simulations
• Gamma-ray observations of Tycho's SNR with VERITAS and Fermi
• Radio and X-ray Observations of the Type Ic SN 2007gr Reveal an Ordinary, Non-relativistic Explosion
• The gas density around SN 1006
• The Destruction of the Circumstellar Ring of SN 1987A
• Bullets in a Core Collapse Supernova Remnant: The Vela Remnant
• The First X-Ray Proper-Motion Measurements of the Forward Shock in the Northeastern Limb of SN 1006
• Cosmic ray diffusion near the Bohm limit in the Cassiopeia A supernova remnant
• Study of TeV shell supernova remnants at gamma-ray energies
• Deeper H.E.S.S. observations of Vela Junior (RX J0852.0$-$4622): Morphology studies and resolved spectroscopy
• Suzaku wide-band observations of SN 1006
• Supernova remnants in clumpy media: particle propagation and gamma-ray emission
• The supernova remnant W44: a case of cosmic-Ray reacceleration
• A detailed study of the interstellar protons toward the TeV $\gamma$-ray SNR RX J0852.0$-$4622 (G266.2$-$1.2, Vela Jr.); a third case of the $\gamma$-rays and ISM spatial correspondence
• Radio Galaxy NGC 1265 unveils the Accretion Shock onto the Perseus Galaxy Cluster
• The Efficiency of Magnetic Field Amplification at Shocks by Turbulence
• The effect of cosmic-ray acceleration on supernova blast wave dynamics
• Results from an Einstein@Home search for continuous gravitational waves from Cassiopeia A, Vela Jr. and G347.3
• Hadronic versus leptonic origin of the gamma-ray emission from Supernova Remnant RX J1713.7-3946
• On the shape of the gamma-ray spectrum around the "${\pi }^0$-bump"
• The Likely Fermi detection of the supernova remnant SN 1006
• On the Nature of the TeV Emission from the SNR SN 1006
• Observational constraints on the modeling of SN1006
• A Morphological Study of the Supernova Remnant RX J0852.0-4622 (Vela Jr.)
• Molecular and atomic gas in the young TeV γ-ray SNRs RX J1713.7-3946 and RX J0852.0-4622; evidence for the hadronic production of γ-rays
• Gamma-ray emission from young supernova remnants: hadronic or leptonic?
• Supernova of 1006 (G327.6+14.6)
• A New Model For Vela Jr. Supernova Remnant

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