Is Supernova Remnant Cassiopeia A a PeVatron?
Zhang,Xiao1,2; Liu,Siming3
Source PublicationThe Astrophysical Journal
AbstractAbstract Cassiopeia A, a well-observed young core-collapse supernova remnant (SNR), is considered to be one of the best candidates for studying very high-energy particle acceleration up to PeV via the diffusive shock mechanism. Recently, MAGIC observations revealed a γ-ray spectral cutoff at ~ 3.5 TeV , suggesting that if the TeV γ-rays have a hadronic origin, SNR Cas A can only accelerate particles to tens of TeV. Here, we propose a two-zone emission model for regions associated with the forward (zone 1) and inward/reverse shocks (zone 2). Given the low density in zone 1, it dominates the high-frequency radio emission, soft X-ray rim via the synchrotron process, and TeV γ-ray via the inverse Comptonization. With a relatively softer particle distribution and a higher cutoff energy for electrons, emissions from zone 2 dominate the low-frequency radio, hard X-ray via the synchrotron process and GeV γ-ray via hadronic processes. There is no evidence for high-energy cutoffs in the proton distributions implying that Cas A can still be a PeVatron. Hadronic processes from zone 1 dominate very high-energy gamma-ray emission. Future observations in the hundreds of TeV range can test this model.
KeywordISM: individual objects (G111.7-2.1=Cassiopeia A) ISM: supernova remnants radiation mechanisms: non-thermal
WOS IDIOP:0004-637X-874-1-ab09fe
PublisherThe American Astronomical Society
Citation statistics
Document Type期刊论文
Affiliation1.School of Astronomy & Space Science, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, People's Republic of China;
2.Key Laboratory of Modern Astronomy and Astrophysics, Nanjing University, Ministry of Education, Nanjing 210023, People's Republic of China
3.Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, 8 Yuanhua Road, Nanjing 210034, People's Republic of China;
Recommended Citation
GB/T 7714
Zhang,Xiao,Liu,Siming. Is Supernova Remnant Cassiopeia A a PeVatron?[J]. The Astrophysical Journal,2019,874(1).
APA Zhang,Xiao,&Liu,Siming.(2019).Is Supernova Remnant Cassiopeia A a PeVatron?.The Astrophysical Journal,874(1).
MLA Zhang,Xiao,et al."Is Supernova Remnant Cassiopeia A a PeVatron?".The Astrophysical Journal 874.1(2019).
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[Zhang,Xiao]'s Articles
[Liu,Siming]'s Articles
Baidu academic
Similar articles in Baidu academic
[Zhang,Xiao]'s Articles
[Liu,Siming]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[Zhang,Xiao]'s Articles
[Liu,Siming]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.