TY - JOUR
T1 - New debris-disk candidates
T2 - 24 Micron stellar excesses at 100 million years
AU - Gorlova, Nadya
AU - Padgett, Deborah L.
AU - Rieke, George H.
AU - Muzerolle, James
AU - Morrison, Jane E.
AU - Gordon, Karl D.
AU - Engelbracht, Chad W.
AU - Hines, Dean C.
AU - Hinz, Joannah C.
AU - Noriega-Crespo, Alberto
AU - Rebull, Luisa
AU - Stansberry, John A.
AU - Stapelfeldt, Karl R.
AU - Su, Kate Y.L.
AU - Young, Erick T.
PY - 2004/9
Y1 - 2004/9
N2 - Sixty-three members of the 100 Myr old open cluster M47 (NGC 2422) have been detected at 24 μm with the Spitzer Space Telescope. The Be star V 378 Pup shows an excess both in the near-infrared and at 24 μm (K - [24] = 2.4 mag), probably due to free-free emission from the gaseous envelope. Seven other early-type stars show smaller excesses, K - [24] = 0.6-0.9. Among late-type stars, two show large excesses: P922, a K1 V star with K - [24] = 1.08 ± 0.11, and P1121, an F9 V star with K - [24] = 3.72 ± 0.02. P1121 is the first known main-sequence star showing an excess comparable to that of β Pic, which may indicate the presence of an exceptionally massive debris disk. It is possible that a major planetesimal collision has occurred in this system, consistent with the few hundred Myr timescales estimated for the clearing of the solar system.
AB - Sixty-three members of the 100 Myr old open cluster M47 (NGC 2422) have been detected at 24 μm with the Spitzer Space Telescope. The Be star V 378 Pup shows an excess both in the near-infrared and at 24 μm (K - [24] = 2.4 mag), probably due to free-free emission from the gaseous envelope. Seven other early-type stars show smaller excesses, K - [24] = 0.6-0.9. Among late-type stars, two show large excesses: P922, a K1 V star with K - [24] = 1.08 ± 0.11, and P1121, an F9 V star with K - [24] = 3.72 ± 0.02. P1121 is the first known main-sequence star showing an excess comparable to that of β Pic, which may indicate the presence of an exceptionally massive debris disk. It is possible that a major planetesimal collision has occurred in this system, consistent with the few hundred Myr timescales estimated for the clearing of the solar system.
KW - Infrared: stars
KW - Open clusters and associations: individual (M47)
KW - Planetary systems: protoplanetary disks
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U2 - 10.1086/422822
DO - 10.1086/422822
M3 - Article
AN - SCOPUS:5644285593
SN - 0067-0049
VL - 154
SP - 448
EP - 452
JO - Astrophysical Journal, Supplement Series
JF - Astrophysical Journal, Supplement Series
IS - 1
ER -