The Peculiar Periodic YSO WL 4 in Rho Ophiuchus

Abstract

We present the discovery of 130.87 day periodic near-infrared flux variability for the Class II T Tauri star WL 4 (= 2MASS J16271848-2429059, ISO-Oph 128). Our data are from the 2MASS Calibration Point Source Working Database, and constitute 1580 observations in J, H and Ks of a field in Rho Ophiuchus used to calibrate the 2MASS All-Sky Survey. We identify a light curve for WL 4 with eclipse amplitudes of ~0.4 mag lasting more than one-quarter the period, and color variations in J-H and H-Ks of ~0.1 mag. The long period cannot be explained by stellar rotation. We propose that WL 4 is a triple YSO system, with an inner binary orbital period of 130.87 days. We posulate that we are observing each component of the inner binary alternately being eclipsed by a circum-binary disk with respect to our line of sight. This system will be useful in investigating terrestrial zone YSO disk properties and dynamics at ~1 Myr.

ApJ Letters, accepted

References in corpus (7)

• Accretion in the Rho-Oph pre-main sequence stars
• A Submillimeter View of Circumstellar Dust Disks in $\rho$ Ophiuchus
• On the Distance to the Ophiuchus Star-Forming Region
• Near-Infrared Variability in the 2MASS Calibration Fields: A Search for Planetary Transit Candidates
• The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds: VII. Ophiuchus Observed with MIPS
• The Orbit and Occultations of KH 15D
• Deep near-IR variability survey of pre-main-sequence stars in Rho Ophiuchi

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