TY - JOUR
T1 - HD 172555
T2 - Detection of 63 μ m [OI] emission in a debris disc
AU - Riviere-Marichalar, P.
AU - Barrado, D.
AU - Augereau, J. C.
AU - Thi, W. F.
AU - Roberge, A.
AU - Eiroa, C.
AU - Montesinos, B.
AU - Meeus, G.
AU - Howard, C.
AU - Sandell, G.
AU - Duchêne, G.
AU - Dent, W. R.F.
AU - Lebreton, J.
AU - Mendigutía, I.
AU - Huélamo, N.
AU - Ménard, F.
AU - Pinte, C.
PY - 2012/1/1
Y1 - 2012/1/1
N2 - Context. HD 172555 is a young A7 star belonging to the β Pictoris moving group that harbours a debris disc. The Spitzer/IRS spectrum of the source showed mid-IR features such as silicates and glassy silica species, indicating the presence of a warm dust component with small grains, which places HD 172555 among the small group of debris discs with such properties. The IRS spectrum also shows a possible emission of SiO gas. Aims. We aim to study the dust distribution in the circumstellar disc of HD 172555 and to asses the presence of gas in the debris disc. Methods. As part of the GASPS open time key programme, we obtained Herschel/PACS photometric and spectroscopic observations of the source. We analysed PACS observations of HD 172555 and modelled the spectral energy distribution with a modified blackbody and the gas emission with a two-level population model with no collisional de-excitation. Results. We report for the first time the detection of [OI] atomic gas emission at 63.18 μm in the HD 172555 circumstellar disc. We detect excesses due to circumstellar dust toward HD 172555 in the three photometric bands of PACS (70, 100, and 160 μm). We derive a large dust particle mass of (4.8 ± 0.6) × 10-4 M⊕ and an atomic oxygen mass of 2.5 × 10-2R2 M⊕, where R in AU is the separation between the star and the inner disc. Thus, most of the detected mass of the disc is in the gaseous phase.
AB - Context. HD 172555 is a young A7 star belonging to the β Pictoris moving group that harbours a debris disc. The Spitzer/IRS spectrum of the source showed mid-IR features such as silicates and glassy silica species, indicating the presence of a warm dust component with small grains, which places HD 172555 among the small group of debris discs with such properties. The IRS spectrum also shows a possible emission of SiO gas. Aims. We aim to study the dust distribution in the circumstellar disc of HD 172555 and to asses the presence of gas in the debris disc. Methods. As part of the GASPS open time key programme, we obtained Herschel/PACS photometric and spectroscopic observations of the source. We analysed PACS observations of HD 172555 and modelled the spectral energy distribution with a modified blackbody and the gas emission with a two-level population model with no collisional de-excitation. Results. We report for the first time the detection of [OI] atomic gas emission at 63.18 μm in the HD 172555 circumstellar disc. We detect excesses due to circumstellar dust toward HD 172555 in the three photometric bands of PACS (70, 100, and 160 μm). We derive a large dust particle mass of (4.8 ± 0.6) × 10-4 M⊕ and an atomic oxygen mass of 2.5 × 10-2R2 M⊕, where R in AU is the separation between the star and the inner disc. Thus, most of the detected mass of the disc is in the gaseous phase.
KW - Circumstellar matter
KW - Kuiper belt: General
KW - Line: Formation
KW - Stars: Individual: HD 172555
KW - Stars: Pre-main sequence
UR - http://www.scopus.com/inward/record.url?scp=84867504101&partnerID=8YFLogxK
U2 - 10.1051/0004-6361/201219745
DO - 10.1051/0004-6361/201219745
M3 - Article
AN - SCOPUS:84867504101
VL - 546
JO - Astronomy & Astrophysics
JF - Astronomy & Astrophysics
SN - 0004-6361
M1 - L8
ER -