CSI 2264: Probing the inner disks of AA Tauri-like systems in NGC 2264

摘要: Context. The classical T Tauri star (CTTS) AA Tau has presented photometric variability that was attributed to an inner disk warp, caused by the interaction between and inclined magnetosphere. Previous studies of young cluster NGC 2264 have shown similar behavior is common among CTTS. Aims. goal this work investigate main causes observed CTTS in present Tau-like light curves, verify if warp could be responsible for their variability. Methods. In order understand mechanism causing these stars’ behavior, we veiling spectra u − r color variations estimate parameters using occultation model proposed Tau. We also compare infrared Spitzer IRAC optical CoRoT curves analyze dust occultations. Results. proved transient on a timescale few years. ascribe stable accretion regimes aperiodic unstable show transition, even coexistence, two common. find evidence hot spots associated with occultations, indicating occulting structures located at base columns. average values maximum height 0.23 times its radial location, consistent Tau, 11% rotation cycles. extinction laws indicate presence grains larger than interstellar grains. Conclusions. scenario observations all but one our sample. systems are fairly common, comprising 14% 2264, though number increases 35% mass 0.7 M_⊙ ≲ M 2.0 M_⊙. Assuming random inclinations, nearly range likely possess warp. attribute possible change magnetic field configurations stars lower mass.