Probable association of T Tauri stars with the L1014 dense core

Using the Wide Field Grism Spectrograph 2 (WFGS2), we have carried out slit-less spectroscopy, g'r'i' photometry, and slit spectroscopy on the L1014 dense core. We detected three Halpha emission line stars. We interpret one as weak-line T Tauri star (WTTS) and the others as classical T Tauri stars (CTTS). Since their g'-i' colors and/or classified spectral types are consistent with those of T Tauri stars and two of them show less extinction than the cloud, these three stars are likely to be T Tauri stars associated with L1014. Adopting an age range for T Tauri stars, 1-10 Myr, the color-magnitude diagram suggests a distance of ~400-900 pc, rather than the previously assumed distance, 200 pc. This could strongly affect on the mass estimate of L1014-IRS, which is thought to be either a very young protostar or proto-brown dwarf.Comment: 5 pages, 5 figures, to be published in Vol.58, No.5, October 25, 200

On the Warped Disk in NGC 4258

We investigate evolution of the warped disk induced by torque due to radiation pressure from the central object. The warp is treated as a small perturbation on to a standard disk model around a supermassive black hole. We derive simultaneous differential equations which govern the development of the warp. Applying our procedure to NGC 4258, we specify the mass of the black hole M=3.9x10^7 M_sun, the accretion rate M=8.6x10^-4 M_sun yr^-1 and the luminosity L=1.0x10^44 erg s^-1. The initial small tilt angle of the disk grows by a factor of 54 during 10 Gyr. It is found that the resulting warped disk can be well superposed on the observed map of water maser emitting clouds