6月23日（火）13：30～15：00 太陽系小天体セミナー zoom
Jun 23 Tue Solar System Minor Body Seminar
6月24日（水）13：30～15：00 NAOJ Science Colloquium zoom
Jun 24 Wed
6月26日（金）13：30～15：00 太陽天体プラズマセミナー zoom
Jun 26 Fri Solar and Space Plasma Seminar
6月26日（金）16：00～17：00 談話会 zoom
Jun 26 Fri NAOJ Seminar
詳細は以下をご覧下さい。
6月23日（火）
- キャンパス
- 三鷹
- セミナー名
- 太陽系小天体セミナー
- 定例・臨時の別
- 定例
- 日時
- 6月23日（火曜日）13時30分～15時
- 場所
- zoom
- 講演者
- 佐藤幹哉
- 連絡先
- 名前：渡部潤一
- 備考
- テレビ会議またはスカイプによる参加も可
6月24日（水）
- Campus
- Mitaka
- Seminar
- NAOJ Science Colloquium
- Regularly Scheduled/Sporadic
- Wednesday
- Date and time
- 6/24 13:30-15:00
- Place
- Zoom
- Speaker
- Kei Tanaka
- Affiliation
- ALMA project, NAOJ
- Title
- On the Birth of Massive Stars
- Abstract
- Massive stars play a lot of essential roles in a wide range of astrophysical settings throughout cosmic history, and thus it is crucial to understand how they form. Compared to low-mass star formation whose standard scenario has been established in the 1980s, research on massive star formation has been dramatically developing in recent years. In this talk, I will introduce our recent theoretical and observational studies on massive star formation. We developed the first model including multiple feedback processes, i.e., MHD disk wind, radiation pressure, photo-ionization, and stellar winds. Our model suggested that, unlike the conventional picture, the MHD disk wind is the dominant feedback rather than radiative feedback, even in the formation of very massive stars (>100Msun). Along with the theoretical works, we also conducted high-resolution ALMA observations to unveil massive protostars that are still deeply embedded in molecular clouds. Utilizing radiative transfer modeling, we measured the photo-evaporation rate from a 40Msun protostar as ~3e-5Msun/yr, which is consistent with our theoretical predictions. Moreover, we detected rich dynamical and chemical structures, such as the rotating envelopes/disks, synchrotron jets, and massive proto-binaries. One of the most exciting findings is that the refractory molecules, such as salt (NaCl), and silicon compounds (SiO, SiS), associated with massive protostellar disks at several hundred au. These “hot-disk” chemistry would have great potential for future research developing from the classic hot-core chemistry. Finally, to connect the present-day and the early universe, we will also discuss massive star formation at low-metallicity environments based on our new theoretical and observational studies.
- Facilitator
- -Name：Akimasa Kataoka
6月26日（金）
- Campus
- Mitaka
- Seminar
- Solar and Space Plasma Seminar
- Regularly Scheduled/Sporadic
- Regular
- Date and time
- 26 June (Fri), 13:30-15:00
- Place
- zoom
- Speaker
- Yukio Katsukawa
- Affiliation
- SSO/NAOJ
- Title
- Progress of the SUNRISE-III Balloon-Borne Solar Observatory
- Abstract
-
The SUNRISE balloon-borne solar observatory carries a 1 m aperture optical telescope,
and provides us a unique platform to perform seeing-free continuous observations at
UV-visible-IR wavelengths from an altitude higher than 35 km. The Japanese team is
developing a specro-polarimeter instrument called SCIP (Sunrise Chromospheric Infrared
spectroPolarimeter) for the next flight planned for 2022. SCIP aims to conduct
spectro-polarimetric observations of multiple spectral lines in near-IR around 770 nm and 850 nm with spatial and spectral resolution of 0.2″ and 2e5, respectively, and with
0.03% (1 sigma) polarimetric sensitivity for 10 sec integration. To achieve the above
performance, we have developed key techniques such as opto-mechanical system less
sensitive to thermal environment, polarization optics and modulator, and high-speed
scanning mechanism. The control electronics and cameras are developed by collaboration
with the Spanish team, for which we are just starting the tests combined with the
Japanese components. Although the flight schedule was delayed for one year due to
unavoidable situation, all the participating institutes are now working hard to
realize the flight in 2022. - Facilitator
- -Name：Munehito Shoda
6月26日（金）
- Campus
- Mitaka
- Seminar
- NAOJ Seminar (国立天文台談話会)
- Regularly Scheduled/Sporadic
- Sporadic
- Date and time
- 6/26 (Fri) 16:00-17:00
- Place
- Zoom
- Speaker
- Assoc.Prof. Yuka Fujii (藤井 友香)
- Affiliation
- Division of Science, NAOJ
- Title
- “Atmospheric Modeling and Observational Prospects for Potentially Habitable Planets around Low-mass Stars’
- Abstract
- The era of characterization of temperate terrestrial (“potentially habitable”) planets will first focus on those around low-mass stars, because their modest planet-to-star ratios in mass/radius/flux are advantageous in various observational techniques to detect faint planetary signals. While having the size and incident flux similar to Earth’s, temperate terrestrial planets around low-mass stars are likely to have undergone extreme stellar environment, and characterization of their atmospheres is crucial to assess their potential for harboring life. They may produce distinctive observable features due to the probable synchronous rotation and the different irradiation spectra. I will discuss the modeling efforts for their atmospheres and some of the possible observational strategies with upcoming missions.
- Facilitator
- -Name：Akimasa Kataoka