Molecular and Atomic Clouds Associated with the Gamma-Ray Supernova Remnant Puppis A

Abstract

We have carried out a study of the interstellar medium (ISM) toward a shell-like supernova remnant SNR Puppis A by using the NANTEN CO and ATCA HI data. We synthesized a comprehensive picture of the SNR radiation by combining the ISM data with the gamma-ray and X-ray distributions. The ISM, both atomic and molecular gas, is dense and highly clumpy, and is distributed all around the SNR, but mainly in the north-east. The CO distribution revealed an enhanced line intensity ratio of CO($J$ = 2-1)/($J$ = 1-0) transitions as well as CO line broadening, which indicate shock heating/acceleration. The results support that Puppis A is located at 1.4 kpc, in the local arm. The ISM interacting with the SNR has a large mass of $\sim$10${}^4$ $M_{\odot }$ which is dominated by HI, showing good spatial correspondence with the Fermi-LAT gamma-ray image. This favors the hadronic origin of the gamma-rays, while additional contribution of the leptonic component is not excluded. The distribution of the X-ray ionization timescales within the shell suggests that the shock front ionized various parts of the ISM at epochs ranging over a few to ten 1000 yr. We therefore suggest that the age of the SNR is around 10${}^4$ yr as given by the largest ionization timescale. We estimate the total cosmic ray energy $W_{\mathrm{p}}$ to be 10${}^{47}$ erg, which is well placed in the cosmic-ray escaping phase of an age-$W_{\mathrm{p}}$ plot including more than ten SNRs.

17 pages, 12 figures, accepted for publication in The Astrophysical Journal (ApJ)

References in corpus (14)

• Optically thick HI dominant in the local interstellar medium; an alternative interpretation to "dark gas"
• X-ray Emitting Ejecta in Puppis A Observed with Suzaku
• High-Resolution X-Ray Spectroscopy of the Galactic Supernova Remnant Puppis A with the XMM-Newton RGS
• A high resolution HI study towards the supernova remnant Puppis A and its environments
• 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
• IRAM-30m large scale survey of ${}^{12}$CO(2-1) and ${}^{13}$CO(2-1) emission in the Orion molecular cloud
• ALMA CO Observations of the Mixed-Morphology Supernova Remnant W49B: Efficient Production of Recombining Plasma and Hadronic Gamma-rays via Shock-Cloud Interactions
• Pursuing the origin of the gamma rays in RX J1713.7$-$3946 quantifying the hadronic and leptonic components
• The Proper Motion of the Central Compact Object RX J0822-4300 in the Supernova Remnant Puppis A, Revisited
• Discovery of a Wind-Blown Bubble Associated with the Supernova Remnant G346.6-0.2: A Hint for the Origin of Recombining Plasma
• High resolution CO observations towards the Bright Eastern Knot of the SNR Puppis A
• An Expanding Shell of Neutral Hydrogen Associated with SN 1006: Hints for the Single-Degenerate Origin and Faint Hadronic Gamma-Rays
• A global view of shocked plasma in the supernova remnant Puppis A provided by SRG/eROSITA
• Probing the origin of 4FGL J0822.8-4207: cosmic ray illumination from the SNR Puppis A and the Herbig-Haro object HH219

Cited by in corpus (2)

• Absorption Line Observations of H${}_3^{+}$ and CO in Sight Lines Toward the Vela and W28 Supernova Remnants
• Evidence for protons accelerated and escaped from the Puppis A region using \textit{Fermi}-LAT observations