Large-field CO(1--0) observations toward the Galactic historical supernova remnants: a large cavity around Tycho's supernova remnant

Abstract

The investigation of the interaction between the supernova remnants (SNRs) and interstellar gas is not only necessary to improve our knowledge of SNRs, but also to understand the nature of the progenitor systems. As a part of the Milky Way Imaging Scroll Painting CO line survey (MWISP), we study the interstellar gas surrounding the Galactic historical SNRs, using the PMO 13.7-meter telescope. In this work, we present large-field (3${}^{\circ }$$\times$2${}^{\circ }$) and high-sensitivity CO(1-0) molecular line observations toward Tycho's SNR. The CO observations reveal, from the outside in, large molecular clouds, stream-like structures, and an inner rim around Tycho's SNR. We derived the basic properties (column density, mass, and kinematics) of these objects based on the CO observations. The large molecular clouds individually show an arc toward the remnant center, outlining a large cavity with radii of $\sim$0.3${}^{\circ }$$\times$0.6${}^{\circ }$ (or 13 pc $\times$27 pc at a distance of 2.5 kpc) around the remnant. The CO line broadenings and asymmetries detected in the surrounding clouds, the observed expansion of the cavity, in concert with enhanced ${}^{12}$CO(2-1)/(1-0) intensity ratio detected in previous studies, suggest the interaction of the large cavity with a wind in the region. After excluding the scenario of a large bubble produced by bright massive stars, we suggest that the large cavity could be explained by accretion wind from the progenitor system of Tycho's supernova. Nevertheless, the possibility of the random distribution of a large cavity around Tycho's SNR cannot be ruled out thus far. Further observations are needed to confirm the physical association of the large cavity with Tycho's SNR.

15 pages, 9 figures, updated according to the A&A proof

References in corpus (7)

• Tycho Brahe's 1572 supernova as a standard type Ia explosion revealed from its light echo spectrum
• Radio emission from Supernova Remnants
• Scattered-Light Echoes from the Historical Galactic Supernovae Cassiopeia A and Tycho (SN 1572)
• Opacity broadening and interpretation of suprathermal CO linewidths: Macroscopic Turbulence and Tangled Molecular Clouds
• The many sides of RCW 86: a type Ia supernova remnant evolving in its progenitor's wind bubble
• Expanding molecular bubble surrounding Tycho's supernova remnant (SN 1572) observed with IRAM 30 m telescope: evidence for a single-degenerate progenitor
• Discovery of a pre-existing molecular filament associated with supernova remnant G127.1+0.5

Cited by in corpus (9)

• The Milky Way Imaging Scroll Painting (MWISP): Project Details and Initial Results from the Galactic Longitude of 25.8deg to 49.7deg
• The CARMA-NRO Orion Survey
• Molecular Clouds associated with the Type Ia SNR N103B in the Large Magellanic Cloud
• Chemical abundances in Sgr A East: evidence for a Type Iax supernova remnant
• Time Variability of Nonthermal X-ray Stripes in Tycho's Supernova Remnant with Chandra
• An explanation of the formation of the peculiar periphery of Tycho's supernova remnant
• Supernova remnant G46.8-0.3, a new case of interaction with molecular material
• Large-field CO (J=1-0) observations toward SNR G150.3+4.5
• IRAM 30 m CO-line Observation toward PeVatron Candidate G106.3+2.7: Direct Interaction between the Shock and the Molecular Cloud Remains Uncertain