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New debris disk candidates: 24 micron stellar excesses at 100 Myr

Nadya Gorlova·Deborah L. Padgett·George H. Rieke·James Muzerolle·Jane E. Morrison·Chad W. Engelbracht·Karl D. Gordon·Dean C. Hines·Joannah C. Hinz·Alberto Noriega-Crespo·Luisa Rebull·John A. Stansberry·Karl R. Stapelfeldt·Kate Y. L. Su·Erick T. Young
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Abstract

Sixty three members of the 100 Myr old open cluster M47 (NGC 2422) have been detected at 24 micron with Spitzer. The Be star V 378 Pup shows an excess both in the near-infrared and at 24 micron (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 K1V star with K-[24] = 1.08 pm 0.11 and P1121 - an F9V star with K-[24] = 3.72 pm 0.02. P1121 is the first known main-sequence star showing an excess comparable to that of beta 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 time scales estimated for the clearing of the Solar System.

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Nadya Gorlova, Deborah L. Padgett, George H. Rieke, James Muzerolle, Jane E. Morrison, Chad W. Engelbracht, Karl D. Gordon, Dean C. Hines, Joannah C. Hinz, Alberto Noriega-Crespo, Luisa Rebull, John A. Stansberry, Karl R. Stapelfeldt, Kate Y. L. Su, Erick T. Young. 2004-06-01. New debris disk candidates: 24 micron stellar excesses at 100 Myr. https://doi.org/10.1086/422822

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