A Caltech Library Service

GASPS—A Herschel Survey of Gas and Dust in Protoplanetary Disks: Summary and Initial Statistics

Dent, W. R. F. and Ardila, D. and Ciardi, D. (2013) GASPS—A Herschel Survey of Gas and Dust in Protoplanetary Disks: Summary and Initial Statistics. Publications of the Astronomical Society of the Pacific, 125 (927). pp. 477-505. ISSN 0004-6280. doi:10.1086/670826.

PDF - Published Version
See Usage Policy.

PDF - Submitted Version
See Usage Policy.


Use this Persistent URL to link to this item:


We describe a large-scale far-infrared line and continuum survey of protoplanetary disk through to young debris disk systems carried out using the ACS instrument on the Herschel Space Observatory. This Open Time Key program, known as GASPS (Gas Survey of Protoplanetary Systems), targeted ∼250 young stars in narrow wavelength regions covering the [OI] fine structure line at 63 μm the brightest far-infrared line in such objects. A subset of the brightest targets were also surveyed in [OI]145 μm, [CII] at 157 μm, as well as several transitions of H_2O and high-excitation CO lines at selected wavelengths between 78 and 180 μm. Additionally, GASPS included continuum photometry at 70, 100 and 160 μm, around the peak of the dust emission. The targets were SED Class II–III T Tauri stars and debris disks from seven nearby young associations, along with a comparable sample of isolated Herbig AeBe stars. The aim was to study the global gas and dust content in a wide sample of circumstellar disks, combining the results with models in a systematic way. In this overview paper we review the scientific aims, target selection and observing strategy of the program. We summarise some of the initial results, showing line identifications, listing the detections, and giving a first statistical study of line detectability. The [OI] line at 63 μm was the brightest line seen in almost all objects, by a factor of ∼10. Overall [OI]63 μm detection rates were 49%, with 100% of HAeBe stars and 43% of T Tauri stars detected. A comparison with published disk dust masses (derived mainly from sub-mm continuum, assuming standard values of the mm mass opacity) shows a dust mass threshold for [OI]63 μm detection of ∼10^(-5) M_⊙. Normalising to a distance of 140 pc, 84% of objects with dust masses ≥10^(-5) M_⊙ can be detected in this line in the present survey; 32% of those of mass 10^(-6)–10^(-5) M_⊙, and only a very small number of unusual objects with lower masses can be detected. This is consistent with models with a moderate UV excess and disk flaring. For a given disk mass, [OI] detectability is lower for M stars compared with earlier spectral types. Both the continuum and line emission was, in most systems, spatially and spectrally unresolved and centred on the star, suggesting that emission in most cases was from the disk. Approximately 10 objects showed resolved emission, most likely from outflows. In the GASPS sample, [OI] detection rates in T Tauri associations in the 0.3–4 Myr age range were ∼50%. For each association in the 5–20 Myr age range, ∼2 stars remain detectable in [OI]63 μm, and no systems were detected in associations with age >20 Myr. Comparing with the total number of young stars in each association, and assuming a ISM-like gas/dust ratio, this indicates that ∼18% of stars retain a gas-rich disk of total mass ∼1 M_(Jupiter) for 1–4 Myr, 1–7% keep such disks for 5–10 Myr, but none are detected beyond 10–20 Myr. The brightest [OI] objects from GASPS were also observed in [OI]145 μm, [CII]157 μm and CO J = 18 - 17, with detection rates of 20–40%. Detection of the [CII] line was not correlated with disk mass, suggesting it arises more commonly from a compact remnant envelope.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Ciardi, D.0000-0002-5741-3047
Additional Information:© 2013 Astronomical Society of the Pacific. Received 2012 December 31; accepted 2013 April 01; published 2013 May 31. We wish to acknowledge the Herschel Helpdesk for their timely and useful responses. The Grenoble group thanks ANR (contracts BLAN-0221, 0504-01 and 0505-01), European Commission’s 7th Framework program (contract pERG06-GA- 2009-256513), CNES, and PNPS of CNRS/INSU, France for support. PW, IK, and WFT acknowledge funding from the EU FP7-2011 under Grant Agreement nr. 284405. WFT acknowledges a Scottish University physics Alliance fellowship (2006- 2009). PACS has been developed by a consortium of institutes led by MPE (Germany) and including UVIE (Austria); KU Leuven, CSL, IMEC (Belgium); CEA, LAM (France); MPIA (Germany); INAF-IFSI/OAA/OAP/OAT, LENS, SISSA (Italy); IAC (Spain). This development has been supported by the funding agencies BMVIT (Austria), ESA-PRODEX (Belgium), CEA/CNES (France), DLR (Germany), ASI/INAF (Italy), and CICYT/MCYT (Spain).
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Agence Nationale de la Recherche (ANR)BLAN-0221
Agence Nationale de la Recherche (ANR)BLAN-0504-01
Agence Nationale de la Recherche (ANR)BLAN-0505-01
European Commission 7th Framework ProgramPERG06-GA-2009-256513
Centre National d'Études Spatiales (CNES)UNSPECIFIED
Programme National de Physique Stellaire (PNPS)UNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
European Research Council (ERC)284405
Scottish University Physics AllianceUNSPECIFIED
Bundesministerium für Verkehr, Innovation und Technologie (BMVIT)UNSPECIFIED
Commissariat à l’Energie Atomique (CEA)UNSPECIFIED
Deutsches Zentrum für Luft- und Raumfahrt (DLR)UNSPECIFIED
Agenzia Spaziale Italiana (ASI)UNSPECIFIED
Comisión Interministerial de Ciencia y Tecnología (CICYT)UNSPECIFIED
Institut national des sciences de l'Univers (INSU)UNSPECIFIED
Centre National d'Études Spatiales (CNES)UNSPECIFIED
Istituto Nazionale di Astrofisica (INAF)UNSPECIFIED
Ministerio de Ciencia y Tecnología (MCYT)UNSPECIFIED
Issue or Number:927
Record Number:CaltechAUTHORS:20130730-092827205
Persistent URL:
Official Citation:GASPS—A Herschel Survey of Gas and Dust in Protoplanetary Disks: Summary and Initial Statistics W. R. F. Dent, W. F. Thi, I. Kamp, J. P. Williams, F. Menard, S. Andrews, D. Ardila, G. Aresu, J.-C. Augereau, D. Barrado y Navascues, S. Brittain, A. Carmona, D. Ciardi, W. Danchi, J. Donaldson, G. Duchene, C. Eiroa, D. Fedele, C. Grady, I. de Gregorio-Molsalvo, C. Howard, N. Huélamo, A. Krivov, J. Lebreton, R. Liseau, C. Martin-Zaidi, G. Mathews, G. Meeus, I. Mendigutía, B. Montesinos, M. Morales-Calderon, A. Mora, H. Nomura, E. Pantin, I. Pascucci, N. Phillips, C. Pinte, L. Podio, S. K. Ramsay, B. Riaz, P. Riviere-Marichalar, A. Roberge, G. Sandell, E. Solano, I. Tilling, J. M. Torrelles, B. Vandenbusche, S. Vicente, G. J. White, and P. Woitke Publications of the Astronomical Society of the Pacific , Vol. 125, No. 927 (May 2013), pp. 477-505 Published by: The University of Chicago Press on behalf of the Astronomical Society of the Pacific Article DOI: 10.1086/670826 Article Stable URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:39646
Deposited By: Ruth Sustaita
Deposited On:30 Jul 2013 17:09
Last Modified:09 Nov 2021 23:46

Repository Staff Only: item control page