The composition of circumstellar gas and dust in 51 Oph

被引:29
作者
van den Ancker, ME
Meeus, G
Cami, J
Waters, LBFM
Waelkens, C
机构
[1] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA
[2] Univ Amsterdam, Astron Inst Anton Pannekoek, NL-1098 SJ Amsterdam, Netherlands
[3] Katholieke Univ Leuven, Inst Sterrenkunde, B-3001 Heverlee, Belgium
[4] SRON, NL-9700 AV Groningen, Netherlands
关键词
circumstellar matter; stars : emission-line; stars : evolution; stars : 51 Oph; infrared : stars;
D O I
10.1051/0004-6361:20010245
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We analyze ISO archive data of the nearby bright emission-line star 51 Oph, previously classified as a proto-planetary system similar to P Pie. The infrared spectrum reveals the presence of gas-phase emission bands of hot (similar to 850 K) CO, CO(2), H(2)O and NO. In addition to this, partially crystalline silicate dust is present. The solid-state bands and the energy distribution are indicative of dust that has: formed recently, rather than of debris dust. The presence of hot molecular gas and the composition of the circumstellar dust are highly unusual for a young star and are reminiscent of what is found around evolved (AGB) stars, although we exclude the possibility of 51 Oph belonging to this group. We suggest several explanations for the nature of 51 Oph, including a recent episode of mass loss from a Be star, and the recent destruction of a planet-sized body around a young star.
引用
收藏
页码:L17 / L21
页数:5
相关论文
共 35 条
[1]  
BOUWMAN J, 2001, IN PRESS A A
[2]   RADIAL VELOCITIES OF BRIGHT SOUTHERN STARS .3. [J].
BUSCOMBE, W .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1963, 126 (01) :29-36
[3]  
Cami J, 2000, ASTRON ASTROPHYS, V360, P562
[4]  
Clegg PE, 1996, ASTRON ASTROPHYS, V315, pL38
[5]  
COTE J, 1987, ASTRON ASTROPHYS, V176, P93
[6]  
deGraauw T, 1996, ASTRON ASTROPHYS, V315, pL49
[7]  
desEtangs AL, 1997, ASTRON ASTROPHYS, V321, pL39
[8]   High-resolution spectroscopy of Vega-like stars .1. Effective temperatures, gravities and photospheric abundances [J].
Dunkin, SK ;
Barlow, MJ ;
Ryan, SG .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 1997, 286 (03) :604-616
[9]   DETECTION OF SILICATES IN THE 51-OPHIUCHI SYSTEM [J].
FAJARDOACOSTA, SB ;
TELESCO, CM ;
KNACKE, RF .
ASTROPHYSICAL JOURNAL, 1993, 417 (01) :L33-L36
[10]   THE CIRCUMSTELLAR GAS SURROUNDING 51-OPHIUCHI - A CANDIDATE PROTOPLANETARY SYSTEM SIMILAR TO BETA PICTORIS [J].
GRADY, CA ;
SILVIS, JMS .
ASTROPHYSICAL JOURNAL, 1993, 402 (02) :L61-L64