YSOVAR: MID-INFRARED VARIABILITY IN THE STAR-FORMING REGION LYNDS 1688

Gunther H.M.; Cody A.M.; Covey K.R.; Hillenbrand L.A.; Plavchan P.; Poppenhaeger K.; Rebull L.M.; Stauffer J.R.; Wolk S.J.; Allen L.; Bayo, A.; Gutermuth R.A.; Hora J.L.; Meng H.Y.A.; Morales-Calderon, M; et. al.

Keywords: herbig ae/be, accretion, accretion disks; Stars: formation; Stars: pre, main sequence; Stars: protostars; Stars: variables: T Tauri

Abstract

The emission from young stellar objects (YSOs) in the mid-infrared (mid-IR) is dominated by the inner rim of their circumstellar disks. We present IR data from the Young Stellar Object VARiability (YSOVAR) survey of similar to 800 objects in the direction of the Lynds 1688 (L1688) star-forming region over four visibility windows spanning 1.6 yr using the Spitzer Space Telescope in its warm mission phase. Among all light curves, 57 sources are cluster members identified based on their spectral energy distribution and X-ray emission. Almost all cluster members show significant variability. The amplitude of the variability is larger in more embedded YSOs. Ten out of 57 cluster members have periodic variations in the light curves with periods typically between three and seven days, but even for those sources, significant variability in addition to the periodic signal can be seen. No period is stable over 1.6 yr. Nonperiodic light curves often still show a preferred timescale of variability that is longer for more embedded sources. About half of all sources exhibit redder colors in a fainter state. This is compatible with time-variable absorption toward the YSO. The other half becomes bluer when fainter. These colors can only be explained with significant changes in the structure of the inner disk. No relation between mid-IR variability and stellar effective temperature or X-ray spectrum is found.

Más información

Título según WOS: YSOVAR: MID-INFRARED VARIABILITY IN THE STAR-FORMING REGION LYNDS 1688
Título según SCOPUS: Ysovar: Mid-infrared variability in the star-forming region Lynds 1688
Título de la Revista: ASTRONOMICAL JOURNAL
Volumen: 148
Número: 6
Editorial: IOP PUBLISHING LTD
Fecha de publicación: 2014
Idioma: English
DOI:

10.1088/0004-6256/148/6/122

Notas: ISI, SCOPUS