Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Quick Search
My eDoc
Session History
Support Wiki
Direct access to
document ID:

          Institute: MPI für Astronomie     Collection: Publikationen_mpia     Display Documents

ID: 421454.0, MPI für Astronomie / Publikationen_mpia
The rapid outbursting star GM Cep: an EXor in Tr 37?
Authors:Sicilia-Aguilar, Aurora; Merí­n, Bruno; Hormuth, Felix; Ãbrahám, Peter; Henning, Thomas; Kun, Mária; Patel, Nimesh; Juhász, Attila; Brandner, Wolfgang; Hartmann, Lee W.; Csizmadia, Szilárd; Moór, Attila
Date of Publication (YYYY-MM-DD):2008
Title of Journal:The Astrophysical Journal
Start Page:382
End Page:399
Review Status:Peer-review
Audience:Experts Only
Abstract / Description:We present optical, IR, and millimeter observations of the solar-type star 13-277, also known as GM Cep, in the 4 Myr old cluster Tr 37. GM Cep experiences rapid magnitude variations of more than 2 mag at optical wavelengths. We explore the causes of the variability, which seem to be dominated by strong increases in the accretion, being similar to EXor episodes. The star shows high, variable accretion rates (up to ~10-6 Msolar yr-1) and signs of powerful winds, and it is a very fast rotator (Vsini~43 km s-1). Its strong mid-IR excesses reveal a very flared disk and/or a remnant envelope, most likely out of hydrostatic equilibrium. The 1.3 mm fluxes suggest a relatively massive disk (MD~0.1 Msolar). Nevertheless, the millimeter mass is not enough to sustain increased accretion episodes over large timescales, unless the mass is underestimated due to significant grain growth. We finally explore the possibility of GM Cep having a binary companion, which could trigger disk instabilities producing the enhanced accretion episodes.
Free Keywords:Accretion; Accretion Disks; stars: individual (GM Cephei); stars: individual (13-277); Stars: Pre-Main-Sequence; Stars: Variables: Other
External Publication Status:published
Document Type:Article
Communicated by:N. N.
Affiliations:MPI für Astronomie
Identifiers:URL:http://adsabs.harvard.edu/abs/2008ApJ...673..382S [ID No:1]
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.