PACS and SPIRE Spectroscopy of the Red Supergiant VY CMa

Abstract

With a luminosity > 10^5 Lsun and a mass-loss rate of about 2.10-4 Msun/yr, the red supergiant VY CMa truly is a spectacular object. Because of its extreme evolutionary state, it could explode as supernova any time. Studying its circumstellar material, into which the supernova blast will run, provides interesting constraints on supernova explosions and on the rich chemistry taking place in such complex circumstellar envelopes. We have obtained spectroscopy of VYCMa over the full wavelength range offered by the PACS and SPIRE instruments of Herschel, i.e. 55 to 672 micron. The observations show the spectral fingerprints of more than 900 spectral lines, of which more than half belong to water. In total, we have identified 13 different molecules and some of their isotopologues. A first analysis shows that water is abundantly present, with an ortho-to-para ratio as low as 1.3:1, and that chemical non-equilibrium processes determine the abundance fractions in the inner envelope.

References in corpus (8)

• Herschel Space Observatory - An ESA facility for far-infrared and submillimetre astronomy
• The Photodetector Array Camera and Spectrometer (PACS) on the Herschel Space Observatory
• The Herschel-SPIRE instrument and its in-flight performance
• In-flight calibration of the Herschel-SPIRE instrument
• Red supergiants as potential Type IIn supernova progenitors: Spatially resolved 4.6 micron CO emission around VY CMa and Betelgeuse
• Probing the mass-loss history of AGB and red supergiant stars from CO rotational line profiles I. Theoretical model -- Mass-loss history unravelled in VY CMa
• The molecular envelope around the red supergiant VY CMa
• The ISO Long Wavelength Spectrometer line spectrum of VY Canis Majoris and other oxygen-rich evolved stars

Cited by in corpus (19)

• MESS (Mass-loss of Evolved StarS), a Herschel Key Program
• SN2023ixf in Messier 101: A Variable Red Supergiant as the Progenitor Candidate to a Type II Supernova
• Pure rotational spectra of TiO and TiO_2 in VY Canis Majoris
• Fundamental properties and atmospheric structure of the red supergiant VY CMa based on VLTI/AMBER spectro-interferometry
• Detection of anhydrous hydrochloric acid, HCl, in IRC+10216 with the Herschel SPIRE and PACS spectrometers
• Silicon in the dust formation zone of IRC +10216 as observed with PACS and SPIRE on board Herschel
• Aluminium oxide in the optical spectrum of VY Canis Majoris
• Herschel/HIFI deepens the circumstellar NH3 enigma
• Herschel SPIRE and PACS observations of the red supergiant VY CMa: analysis of the molecular line spectra
• Late Stages of Stellar Evolution - Herschel's contributions
• The chemistry of dust formation in red supergiants
• Circumstellar ammonia in oxygen-rich evolved stars
• The mass-loss rates of red supergiants at low metallicity: Detection of rotational CO emission from two red supergiants in the Large Magellanic Cloud
• SOFIA/GREAT Discovery of Terahertz Water Masers
• Arcsecond resolution mapping of Sulfur Dioxide emission in the circumstellar envelope of VY Canis Majoris
• On the influence of collisional rate coefficients on the water vapour excitation
• On the nature of the enigmatic object IRAS 19312+1950: A rare phase of massive star formation?
• On the properties of dust and gas in the environs of V838 Monocerotis
• PACS and SPIRE range spectroscopy of cool, evolved stars