High Resolution HST-STIS Spectra of CI and CO in the Beta Pictoris Circumstellar Disk

Abstract

High resolution FUV echelle spectra showing absorption features arising from CI and CO gas in the Beta Pictoris circumstellar (CS) disk were obtained on 1997 December 6 and 19 using the Space Telescope Imaging Spectrograph (STIS). An unsaturated spin-forbidden line of CI at 1613.376 A not previously seen in spectra of Beta Pictoris was detected, allowing for an improved determination of the column density of CI at zero velocity relative to the star (the stable component), N = (2-4) x 10^{16} cm^{-2}. Variable components with multiple velocities, which are the signatures of infalling bodies in the Beta Pictoris CS disk, are observed in the CI 1561 A and 1657 A multiplets. Also seen for the first time were two lines arising from the metastable singlet D level of carbon, at 1931 A and 1463 A The results of analysis of the CO A-X (0-0), (1-0), and (2-0) bands are presented, including the bands arising from {13}^CO, with much better precision than has previously been possible, due to the very high resolution provided by the STIS echelle gratings. Only stable CO gas is observed, with a column density N(CO) = (6.3 +/- 0.3) x 10^{14} cm{-2}. An unusual ratio of the column densities of {12}^CO to {13}^CO is found (R = 15 +/- 2). The large difference between the column densities of CI and CO indicates that photodissociation of CO is not the primary source of CI gas in the disk, contrary to previous suggestion.

13 pages, including 6 figures. LaTex2e (emulateapj5.sty). Accepted for publication in ApJ

Cited by in corpus (64)

• Circumstellar Debris and Pollution at White Dwarf Stars
• Molecular Gas Clumps from the Destruction of Icy Bodies in the $\beta$ Pictoris Debris Disk
• H2 and CO emission from disks around TTauri and HerbigAe pre-main-sequence stars and from debris disks around young stars: warm and cold circumstellar gas
• An Excess Due to Small Grains Around The Nearby K0V Star HD69830: Asteroid or Cometary Debris?
• The Carbon-Rich Gas in the Beta Pictoris Circumstellar Disk
• Predictions for the secondary CO, C and O gas content of debris discs from the destruction of volatile-rich planetesimals
• ALMA observations of the molecular gas in the debris disk of the 30 Myr old star HD 21997
• Debris from giant impacts between planetary embryos at large orbital radii
• Debris Disks in the Scorpius-Centaurus OB Association Resolved by ALMA
• Exocometary gas structure, origin and physical properties around $\beta$ Pictoris through ALMA CO multi-transition observations
• Molecular gas in debris disks around young A-type stars
• ALMA observations of the $\eta$ Corvi debris disc: inward scattering of CO-rich exocomets by a chain of 3-30 M${}_{\oplus }$ planets?
• Five steps in the evolution from protoplanetary to debris disk
• CO mass upper limits in the Fomalhaut ring - the importance of NLTE excitation in debris discs and future prospects with ALMA
• Gas and dust in the Beta Pictoris Moving Group as seen by the Herschel Space Observatory
• Molecular gas in young debris disks
• On the gas temperature in circumstellar disks around A stars
• Herschel Observations of Gas and Dust in the Unusual 49 Ceti Debris Disk
• The Dust and Gas Around beta Pictoris
• Widespread atomic gas emission reveals the rotation of the beta Pictoris disk
• The Far-Ultraviolet "Continuum" in Protoplanetary Disk Systems II: CO Fourth Positive Emission and Absorption
• Rapid Dissipation of Primordial Gas from the AU Microscopii Debris Disk
• Formation of Narrow Dust Rings in Circumstellar Debris Disks
• ALMA resolves CI emission from the $\beta$ Pictoris debris disk
• Alkaline Exospheres of Exoplanet Systems: Evaporative Transmission Spectra
• Volatile-Rich Circumstellar Gas in the Unusual 49 Ceti Debris Disk
• Molecular reconnaissance of the $\beta$ Pictoris gas disk with the SMA: a low HCN/(CO+CO${}_2$) outgassing ratio and predictions for future surveys
• Herschel detects oxygen in the beta Pictoris debris disk
• Kuiper belt structure around nearby super-Earth host stars
• Detection of submillimeter-wave [C I] emission in gaseous debris disks of 49 Ceti and Beta Pictoris
• Exocomets from a Solar System Perspective
• Ro-vibrational CO Detected in the $\beta$~Pictoris Circumstellar Disk
• The co-existence of hot and cold gas in debris discs
• A Low-Mass H2 Component to the AU Microscopii Circumstellar Disk
• ALMA observations of the multiplanet system 61 Vir: What lies outside super-Earth systems?
• Testing Rotational Mixing Predictions with New Boron Abundances in Main Sequence B-type Stars
• Resolved Gas Interior to the Dust Rings of the HD 141569 Disk
• Lack of other molecules in CO-rich debris discs: is it primordial or secondary gas?
• FUSE Observations of Possible Infalling Planetesimals in the 51 Ophiuchi Circumstellar Disk
• Can gas in young debris disks be constrained by their radial brightness profiles?
• Line emission from circumstellar disks around A stars
• Primordial or Secondary? Testing models of debris disk gas with ALMA
• First Detection of Hydrogen in the β Pictoris Gas Disk
• Gas emission from debris disks around A and F stars
• UV Spectroscopy of Star-Grazing Comets within the 49 Ceti Debris Disk
• Evidence for fresh frost layer on the bare nucleus of comet Hale--Bopp at 32 AU distance
• Polarization from Aligned Dust Grains in the $\beta$ Pic Debris Disk
• Insights into planet formation from debris disks: I. The solar system as an archetype for planetesimal evolution
• Circumstellar discs: What will be next?
• Fe I in the β Pictoris circumstellar gas disk I. Physical properties of the neutral iron gas
• Physical conditions of gas components in debris disks of 49 Ceti and HD 21997
• Curves of growth for transiting exocomets: Application to Fe II lines in the Beta Pictoris system
• The ALMA survey to Resolve exoKuiper belt Substructures (ARKS) IV: CO gas imaging and overview
• A Radiatively Driven Wind from the eta Tel Debris Disk
• Population of excited levels of Fe+, Ni+ and Cr+ in exocomets gaseous tails
• Stellar winds can affect gas dynamics in debris disks and create observable belt winds
• CHEOPS's hunt for exocomets: photometric observations of 5 Vul
• The Age-Dependence of the Detectabiity of Comets Orbiting Solar-Type Stars
• A Constraint on the Amount of Hydrogen from the CO Chemistry in Debris Disks
• Discovery of Volatile Gas in the Giant Impact Disk around the 150-Myr old HD 23514
• Transit distances and composition of low-velocity exocomets in the $\beta$ Pic system
• High CO/H2 ratios supports an exocometary origin for a CO-rich debris disk
• Weakly mass-loaded accretion disks
• The search for gas in debris discs: ALMA detection of CO gas in HD 36546