Detection of warm water vapour in Taurus protoplanetary discs by Herschel

Abstract

Line spectra of 68 Taurus T Tauri stars were obtained with the Herschel-PACS (Photodetector Array Camera & Spectrometer) instrument as part of the GASPS (Gas Evolution in Protoplanetary Systems) survey of protoplanetary discs. A careful examination of the line scans centred on the [OI] 63.18 microns fine-structure line unveiled a line at 63.32 micron in some of these spectra. We identify this line with a transition of ortho-water. It is detected confidently (i.e., >3 sigma) in eight sources, i.e., 24% of the sub-sample with gas-rich discs. Several statistical tests were used to search for correlations with other disc and stellar parameters such as line fluxes of [OI] 6300 Armstrong and 63.18 microns; X-ray luminosity and continuum levels at 63 microns and 850 microns. Correlations are found between the water line fluxes and the [OI] 63.18 microns line luminosity, the dust continuum, and possibly with the stellar X-ray luminosity. This is the first time that this line of warm water vapour has been detected in protoplanetary discs. We discuss its origins, in particular whether it comes from the inner disc and/or disc surface or from shocks in outflows and jets. Our analysis favours a disc origin, with the observed water vapour line produced within 2-3AU from the central stars, where the gas temperature is of the order of 500-600 K.

4 letter pages, 2 appendix pages, 5 images, to be published in Astronomy and Astrophysics

References in corpus (5)

• The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST)
• Detection of the Water Reservoir in a Forming Planetary System
• H2O and OH gas in the terrestrial planet-forming zones of protoplanetary disks
• Quasi-classical rate coefficient calculations for the rotational (de)excitation of H2O by H2
• Water in star-forming regions with Herschel: highly excited molecular emission from the NGC 1333 IRAS 4B outflow

Cited by in corpus (55)

• BANYAN. XI. The BANYAN $\Sigma$ multivariate Bayesian algorithm to identify members of young associations within 150 pc
• Interstellar water chemistry: from laboratory to observations
• Complex organic molecules in protoplanetary disks
• Water in star-forming regions (WISH): Physics and chemistry from clouds to disks as probed by Herschel spectroscopy
• GASPS - a Herschel survey of gas and dust in Protoplanetary Disks: Summary and Initial Statistics
• Evidence for a Snow Line Beyond the Transitional Radius in the TW Hya Protoplanetary Disk
• Water vapor distribution in protoplanetary disks
• Chemo-dynamical deuterium fractionation in the early solar nebula: The origin of water on Earth and in asteroids and comets
• Water vapor in the protoplanetary disk of DG Tau
• A Comprehensive Census of Nearby Infrared Excess Stars
• Gas and dust in the Beta Pictoris Moving Group as seen by the Herschel Space Observatory
• Probing stellar accretion with mid-infrared hydrogen lines
• GASPS observations of Herbig Ae/Be stars with PACS/Herschel. The atomic and molecular content of their protoplanetary discs
• The depletion of water during dispersal of planet-forming disk regions
• Herschel/PACS Survey of protoplanetary disks in Taurus/Auriga -- Observations of [OI] and [CII], and far infrared continuum
• Fluctuations and Flares in the Ultraviolet Line Emission of Cool Stars: Implications for Exoplanet Transit Observations
• Measurements of water surface snow lines in classical protoplanetary disks
• Uncertainties in water chemistry in disks: An application to TW Hya
• Water in star forming regions with Herschel (WISH) III. Far-infrared cooling lines in low-mass young stellar objects
• Herschel/PACS observations of young sources in Taurus: the far-infrared counterpart of optical jets
• The Gould Belt Very Large Array Survey IV: The Taurus-Auriga complex
• The chemistry of disks around T Tauri and Herbig Ae/Be stars
• Origins Space Telescope Mission Concept Study Report
• FUV and X-ray irradiated protoplanetary disks: a grid of models I. The disk structure
• Warm H2O and OH in the disk around the Herbig star HD 163296
• The kinematics and excitation of infrared water vapor emission from planet-forming disks: results from spectrally-resolved surveys and guidelines for JWST spectra
• Understanding the water emission in the mid- and far-IR from protoplanetary disks around T~Tauri stars
• Gas and dust in the TW Hydrae Association as seen by the Herschel Space Observatory
• Candidate Water Vapor Lines to Locate the H${}_2$O Snowline through High-Dispersion Spectroscopic Observations I. The Case of a T Tauri Star
• FUV and X-ray irradiated protoplanetary disks: a grid of models II - Gas diagnostic line emission
• Protoplanetary disks in $K_s$-band total intensity and polarized light
• Dust continuum emission and the upper limit fluxes of sub-millimeter water lines of the protoplanetary disk around HD 163296 observed by ALMA
• Herschel evidence for disk flattening or gas depletion in transitional disks
• Classifying the embedded young stellar population in Perseus and Taurus & the LOMASS database
• On water delivery in the inner solar nebula: Monte Carlo simulations of forsterite hydration
• Mid-IR spectra of Pre-Main Sequence Herbig stars: an explanation for the non-detections of water lines
• Herschel-PACS observations of far-IR lines in YSOs I: [OI] and H2O at 63 microns
• Candidate Water Vapor Lines to Locate the ${\mathrm{H}}_2\mathrm{O}$ Snowline through High-dispersion Spectroscopic Observations. III. Submillimeter ${\mathrm{H}}_2$${}^{16}\mathrm{O}$ and ${\mathrm{H}}_2$${}^{18}\mathrm{O}$ Lines
• Resolved ALMA observations of water in the inner astronomical units of the HL Tau disk
• H${}_2$S observations in young stellar disks in Taurus
• H${}_2$O distribution in the disc of HD 100546 and HD 163296: the role of dust dynamics and planet--disc interaction
• A Combined Spitzer and Herschel Infrared Study of Gas and Dust in the Circumbinary Disk Orbiting V4046 Sgr
• The mid-IR water and silicate relation in protoplanetary disks
• Herschel observations of the circumstellar environment of the two Herbig Be stars R Mon and PDS27
• Velocity-resolved hot water emission detected toward HL Tau with the Submillimeter Array
• Herschel -PACS observations of [OI] and H2O in Cha II
• Absorption of crystalline water ice in the far infrared at different temperatures
• Re-visiting the case of R Mon: Is CO removed at R<20 au?
• Gas kinematics of key prebiotic molecules in GV Tau N revealed with an ALMA, PdBI, and Herschel synergy
• Zooming into the water snowline: high resolution water observations of the HL Tau disk
• Radio emission from flaring stars and brown dwarfs
• H3+ in irradiated protoplanetary disks: Linking far-ultraviolet radiation and water vapor
• Protoplanetary Disk Science with the Orbiting Astronomical Satellite Investigating Stellar Systems (OASIS) Observatory
• Impact of Size-dependent Grain Temperature on Gas-Grain Chemistry in Protoplanetary Disks: the case of low mass star disks
• The formation of planetary systems with SPICA