Date & Time: 2026/January/22 17:15-18:15, Venue: Zoom TV Conference System. This is an informal seminar on the formation of stars and planets. We welcome anyone interested in the subject.
Abstract:
Investigating the early stages of protostars and their natal environments is essential for understanding how initial conditions shape their evolution. With the high sensitivity and angular resolution of ALMA and JWST, we can now directly probe the structures, as well as the physical and chemical properties of individual protostellar systems. In this talk, we first present star formation activity within a filament, Orion Molecular Cloud-3 (OMC-3) region, which hosts 10 pre- and protostellar sources. ALMA observations have further revealed a highly compact and well-collimated SiO jet associated with two of the millimeter sources in OMC-3, named MMS 1 and MMS 6. The jets have projected lengths of ∼2″ (∼800 au), corresponding to dynamical timescales of ∼60 years, making them among the youngest protostellar jets known to date. Position–velocity diagrams along the jet major axes show Hubble-like velocity structures. Comparisons with numerical simulations suggest multiple mass ejection events associated with each Hubble-like flow. Despite MMS 1 and MMS 6 show similarly young jets, the gas and dust emission within the central ∼400 au differs significantly between the two sources. The peak continuum brightness temperature is over 10 times higher in MMS 6 than in MMS 1. Complex organic molecules are detected only toward MMS 6. These differences presumably reflect either slight differences in the evolutionary stage or differences in mass accretion state between the two protostars.
他、会議報告、速報など、飛び入りも歓迎します。今回もしくは次回以降、話題提供できる方は世話人までメールしていただけましたら幸いです。
Participants: 32, Affiliations: 10
Ibaraki Univ P Toru Tsuribe
ICRR A Jiro Shimoda
Kyushu AP Doris Arzoumanian, PD Jihye Hwang, PD Masayuki Yamaguchi, D2 Ayumu Shoshi, D2 Shingo Nozaki, D1 Mitsuki Omura, M2 Reo Sakamoto, B4 Kaho Hata
Nagoya P Shu-ichiro Inutsuka, AP Hiroshi Kobayashi, D3 Ryushi Miyayama, D2 Izumi Seno, D2 Yona Lapeyre, D1 Kenshin Onogawa, M2 Yuji Miko, M2 Hayato Shimizu, M2 Kota Kobayashi, M1 Yuki Tamaki, M1 Kanaho Imata, M1 Taisei Shioya
NAOJ AP Satoko Takahashi, PD Kshitiz Mallick
RIKEN PD Yoshihide Yamato
Science Tokyo PD Ryosuke Tominaga, D2 Shintaro Taira
SOKENDAI D1 Akshat Asthana
UOsaka B4 Hiroki Kitagawa
UTokyo A Shota Notsu, PD Naoto Harada, PD Ryuta Orihara
次回：2026/March/26 17:15-
連絡世話人：冨永遼佑（東京科学大学） tominaga.r.aa[at]m.titech.ac.jp