Home > Solar and Space Plasma (SSP) Seminar | 国立天文台談話会 | 太陽系小天体セミナー | 科学研究部コロキウム > 2020.06.22-2020.6.28

2020.06.22-2020.6.28

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

Home > Solar and Space Plasma (SSP) Seminar | 国立天文台談話会 | 太陽系小天体セミナー | 科学研究部コロキウム > 2020.06.22-2020.6.28

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