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arXiv · 1506.04363

Rapid Dissipation of Protoplanetary Disks in Ophiuchus

Yuhei Takagi·Yoichi Itoh·Akira Arai·Sai Shoko·Yumiko Oasa
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Abstract

We present the results of an age determination study for pre-main sequence stars in the Ophiuchus molecular cloud. The ages of eight pre-main sequence stars were estimated from surface gravities derived from high-resolution spectroscopy. The average age of the target stars was 0.7 Myr. By comparing the individual age and the near-infrared color excess, we found that color excess decreases gradually with a constant rate and the lifetime of the inner disk was determined to be 1.2 Myr. The estimated lifetime is nearly a half of the time compared to that of the pre-main sequence stars in the Taurus molecular cloud estimated with the same method. This result indicates that the disk evolution timescale depends on the environment of the star-forming region.

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Yuhei Takagi, Yoichi Itoh, Akira Arai, Sai Shoko, Yumiko Oasa. 2015-06-14. Rapid Dissipation of Protoplanetary Disks in Ophiuchus. https://doi.org/10.1093/pasj%2Fpsv062

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