2024.6.3-2024.6.9


June 4 Tue 10:00-11:30
太陽系小天体セミナー (Solar System Minor Body Seminar)
Zoom


June 5 Wed 10:30-12:00
SOKENDAI Colloquium
hybrid; Large Seminar Room in Subaru Building and Zoom


詳細は下記からご覧ください。

=============== June 4 Tue===============

キャンパス:三鷹
セミナー名:太陽系小天体セミナー (Solar System Minor Body Seminar)
定例・臨時の別:定例
日時: 6月 4日(火曜日)10時00分~11時30分
場所:zoom
講演者:渡部潤一, 鈴木文二
タイトル: 彗星研究紹介

世話人の連絡先
-名前:渡部潤一

備考:zoomでの参加


=============== June 5 Wed===============

Campus:Mitaka
Seminar:SOKENDAI Colloquium
Regularly Scheduled/Sporadic:Scheduled
Date and time:Jun 05 10:30-12:00
Place:Large Seminar Room in Subaru Building and Zoom

Speaker:Yoshiaki Sato
Affiliation:SOKENDAI 3rd year (D1) (Supervisor:Noriyuki Narukage, Takashi Sekii, Masumi Shimojo)
Title:Introduction of our flare campaign and efforts to predict solar flare scale

Speaker:Tomohiro Yoshida
Affiliation:SOKENDAI 4th year (D2) (Supervisor:Hideko Nomura)
Title:Detection of SO in the protoplanetary disk around TW Hya: outflow from an embedded protoplanet?

Facilitator
-Name:Yoshiaki Sato

Comment:Language: English




2024.5.20-2024.5.26


May 21 Tue 10:00-11:30
太陽系小天体セミナー (Solar System Minor Body Seminar)
Zoom


May 22 Wed 10:30-12:00
SOKENDAI Colloquium
hybrid; Large Seminar Room in Subaru Building and Zoom


May 22 Wed 14:30-15:30
ALMA-J seminar
hybrid; Room 102 in ALMA Building and Zoom


May 22 Wed 15:30-16:30
NAOJ Science Colloquium
hybrid; Large Seminar Room in Subaru Building and Zoom


May 24 Fri 15:30-16:30
NAOJ Seminar
hybrid; Large Seminar Room in Subaru Building and Zoom


詳細は下記からご覧ください。

=============== May 21 Tue===============

キャンパス:三鷹
セミナー名:太陽系小天体セミナー (Solar System Minor Body Seminar)
定例・臨時の別:定例
日時: 5月 21日(火曜日)10時00分~11時30分
場所:zoom
講演者:長谷川均
タイトル: 研究紹介 

世話人の連絡先
-名前:渡部潤一
備考:zoomでの参加

=============== May 22 Wed===============

Campus:Mitaka
Seminar:SOKENDAI Colloquium
Regularly Scheduled/Sporadic:Scheduled
Date and time:May 22, 2024 10:30-12:00
Place:Large Seminar Room in Subaru Building and Zoom

Speaker:Miho Tan
Affiliation:SOKENDAI 2nd year (M2) (Supervisor: Mami Machida, Tomoya Takiwaki, Kazunari Iwasaki)
Title:Effect of companion star wind in the jet propagation from X-ray binary

Speaker:Kiyoaki Doi
Affiliation: SOKENDAI 5th year (D3) (Supervisor: Akimasa Kataoka, Hideko Nomura, Misato Fukagawa)
Title:ALMA Band 3 observations of the protoplanetary disk around PDS 70

Facilitator
-Name:Yoshiaki Sato
Comment:Language: English

===============May 22 Wed==============

Campus: Mitaka
Seminar: ALMA-J seminar
Date and time: 2024 May. 22 (Wed.), 14:30-15:30 JST
Place: Room 102 in ALMA building / Zoom (hybrid)
Speaker: Yumi Watanabe
Affiliation: Fukushima Univ. /NAOJ

Title: Elucidation of anomalies in the HCN(J=1-0)/CO(J=1-0) intensity ratio using nearby Seyfert galaxy

Abstract:
Galaxies and black holes co-evolve. To understand co-evolution, it is necessary to clarify the phenomenon of AGN. To clarify galaxy evolution, we focused on AGN. The phenomenon of AGN can affect the properties of molecular gases, which is why we are studying molecular gases.
HCN(1-0), which traces dense gas, has been used in investigating the physics of AGN.
We focused our study on NGC 1068, a nearby Seyfert galaxy(distance of about 14 Mpc). This galaxy has an AGN and is considered to have a typical stellar mass. It also has a circumnuclear disk (CND) of gas (radius ~0.2 kpc) surrounding the AGN. Therefore, we focused on this galaxy.
In addition to our group’s own data, we collected and synthesized archived data from ALMA telescopes around the world and used high-quality data to observe HCN and CO in NGC 1068. The HCN/CO intensity ratio was created and a maximum value of 1.09 was obtained. This value is unusually higher than the galaxy’s typical value of 0.1. The cause may be abnormal abundance or excitation. We will discuss the cause of the unusually high HCN/CO intensity ratios observed around the CND.

Facilitator
-Name: Yu Cheng

===============May 22 Wed==============

Campus: Mitaka
Seminar: NAOJ Science Colloquium
Date and time: 2024 May 22 (Wed.), 15:30-16:30 JST
Place: the large seminar room / Zoom (hybrid)

Speaker: Arnab Chaudhuri
Affiliation: NAOJ (JSPS)
Title: Excursion beyond the Standard Model Physics- Gravitational Waves and Beyond
Abstract:
The standard model of particle physics, even though very successful, however is incomplete. It fails to explain the origin of the matter-antimatter asymmetry, neutrino masses and have any suitable candidates for dark matter. Within the framework of the standard model electroweak phase transition is crossover in nature. Hence a lot of beyond the standard model theories have been established in both particle physics and cosmology to overcome these shortcomings. The recent results from NANOGrav have also established the existence of secondary or stochastic gravitational waves. In this talk, I will go through some models with the main focus being the creation of these stochastic gravitational waves due to a first order phase transition.

This talk will be primarily based on JCAP 01 (2018) 032, Phys.Rev.D
106 (2022) 9, 095016 and arXiv: 2404.10288 .

Facilitator
-Name: Hiroki Nagakura
Comment: English

===============May 24 Fri==============

Campus:Mitaka
Seminar:NAOJ Seminar
Regularly Scheduled/Sporadic:Regular
Date and time:May 24, 2024 15:30-16:30
Place:Zoom/Large Seminar Room (hybrid)

Speaker:Prof. Tom Millar
Affiliation:Queen’s University Belfast

Title: Gas-phase Astrochemistry: Successes and Challenges

Abstract: The importance of astrochemistry in elucidating physical conditions and processes in astronomy has grown remarkably in recent years in response to the development of novel instruments and observational facilities. As a result, astrochemical techniques are applied to a wide range of astronomical objects, from the solar system to star birth and death, to exoplanet atmospheres, to galaxies and even to the early evolution of the universe. In this talk, I will give a brief history of the development of the subject from its conception around 1950 to its birth, eventually induced by radio astronomy, in 1973.

The importance of astrochemistry as an essentially interdisciplinary discipline will be stressed given the need for gas-phase reaction rate coefficients over a wide temperature range as well as chemistry in and on icy grain mantles. I will introduce the new release of the UMIST Database for Astrochemistry (UDfA) that reflects the additional chemistry needed to model the 100 or so new molecules detected in the last decade.

I will also describe some results from the ATOMIUM project, an ALMA Large Program, aimed at understanding dust formation around O-rich AGB stars. A surprise finding is that all targets have density distributions that appear to be driven by the presence of a binary companion. ATOMIUM results, and ALMA observations of ‘unexpected’ complex molecules at a few stellar radii in the C-rich star IRC+10216, have shown the importance of UV photons from binary companions in determining the chemistry of their inner winds. I will discuss some attempts to explain these results and will finish with some challenges for the future development of the subject.

Facilitator
-Name:Takuma Izumi

2024.5.13-2024.5.19


May 14 Tue 10:00-11:30
太陽系小天体セミナー (Solar System Minor Body Seminar)
Zoom


May 14 Tue 13:00-13:40
SOKENDAI Doctoral Thesis Preliminary Evaluation
総研大博士学位論文予備審査会
hybrid; Large Seminar Room in Subaru Building and Zoom


May 15 Wed 10:30-12:00
SOKENDAI Colloquium
hybrid; Large Seminar Room in Subaru Building and Zoom


May 15 Wed 14:30-15:30
ALMA-J seminar
hybrid; Large Seminar Room in Subaru Building and Zoom


詳細は下記からご覧ください。

=============== May 14 Tue===============

キャンパス:三鷹
セミナー名:太陽系小天体セミナー (Solar System Minor Body Seminar)
定例・臨時の別:定例
日時: 5月 14日(火曜日)10時00分~11時30分
場所:zoom
講演者:佐藤幹哉
所属: 国立天文台 

世話人の連絡先
-名前:渡部潤一
備考:zoomでの参加

=============== May 14 Tue===============

Campus: Mitaka
Seminar: SOKENDAI Doctoral Thesis Preliminary Evaluation
     総研大博士学位論文予備審査会
Regularly Scheduled/Sporadic: Sporadic
Date and time: May 14, 2024 13:00-13:40
Place: Large Seminar Room and Zoom

Speaker: Kiyoaki Doi
Title: Constraining Physical Properties of Protoplanetary Disks from Spatial Distributions of Dust Millimeter Continuum Observations

Facilitator
-Name: Ken’ichi Tatematsu, Tomoya Hirota, Kazunari Iwasaki

(Graduate Student Affairs Unit)

===============May 15 Wed==============

Campus:Mitaka
Seminar:SOKENDAI Colloquium
Regularly Scheduled/Sporadic:Scheduled
Date and time:May 15, 2024 10:30-12:00
Place:Large Seminar Room in Subaru Building and Zoom

Speaker:Abdurrahman Naufal
Affiliation:SOKENDAI 4th year (D2) (Supervisor: Yusei Koyama, Masayuki Tanaka, Yuichi Matsuda)
Title:Deep census of the Spiderweb protocluster members with HST slitless spectroscopy observation

Facilitator
-Name:Yoshiaki Sato
Comment:Language: English

===============May 15 Wed==============

Campus: Mitaka
Seminar: ALMA-J seminar
Date and time: 2024 May. 15 (Wed.), 14:30-15:30 JST
Place: Subaru building, Large seminar room / Zoom (hybrid)

Speaker: Kshitiz Mallick
Affiliation: NAOJ
Title: Observational study of high-mass star formation at the junction of filaments
Abstract:
Understanding high-mass star formation is an important pillar of astronomical research, due to the large impact of such sources on their natal environment.
Various paradigms have been proposed for the formation of such stellar sources, with hub filament systems (HFS) having emerged as an important contender for understanding not only how massive stars form, but also the evolution of a molecular cloud as it collapses and fragments to form stars. In this talk, I present the results of my recent observational analysis of some high-mass star forming regions, carried out using molecular data cubes, complemented by other multiwavelength data. We discuss the complex nature of such star forming regions, the conundrums faced in analysis of hubs and filamentary structures, and the further work one needs to undertake to fully comprehend the connection between(high-mass) star formation and HFS.

Facilitator
-Name: Yu Cheng

2024.5.6-2024.5.12


May 7 Tue 10:00-11:30
太陽系小天体セミナー (Solar System Minor Body Seminar)
Zoom


May 8 Wed 10:30-12:00
SOKENDAI Colloquium
hybrid; Large Seminar Room in Subaru Building and Zoom


May 8 Wed 15:30-16:30
NAOJ Science Colloquium
hybrid; Large Seminar Room in Subaru Building and Zoom


May 10 Fri 15:30-16:30
NAOJ Seminar
hybrid; Large Seminar Room in Subaru Building and Zoom


詳細は下記からご覧ください。

=============== May 7 Tue===============

キャンパス:三鷹
セミナー名:太陽系小天体セミナー (Solar System Minor Body Seminar)
定例・臨時の別:定例
日時: 5月 7日(火曜日)10時00分~11時30分
場所:zoom
講演者:秋澤宏樹

世話人の連絡先
-名前:渡部潤一
備考:zoomでの参加

=============== May 8 Wed===============

Campus:Mitaka
Seminar:SOKENDAI Colloquium
Regularly Scheduled/Sporadic:Scheduled
Date and time:May 8, 2024 10:30-12:00
Place:Large Seminar Room in Subaru Building and Zoom

Speaker:Ryota Ichimura
Affiliation:SOKENDAI 4th year (D2) (Supervisor: Hideko Nomura, Akimasa Kataoka, Nanase Harada)
Title:The impact of Cosmic Rays on Carbon Isotope Fractionation of COMs in Star-Forming Cores

Speaker:Ryota Ikeda
Affiliation: SOKENDAI 4th year (D2) (Supervisor: Daisuke Iono, Masayuki Tanaka, Takuma Izumi)
Title:Resolving Luminous Submillimeter Galaxies

Facilitator
-Name:Yoshiaki Sato
Comment:Language: English

===============May 8 Wed==============

Campus: Mitaka
Seminar: NAOJ Science Colloquium
Date and time: 2023 May 8 (Wed.), 15:30-16:30 JST
Place: the large seminar room / Zoom (hybrid)

Speaker: Yukun Huang
Affiliation: CfCA, Division of Science
Title: A Rogue Planet Hypothesis for the Formation of the Trans-Neptunian Solar System – 太陽系外縁の形成におけるローグ惑星仮説 –
Abstract:
Over the past two decades, our knowledge of the Solar System’s Trans-Neptunian region (often called the Kuiper Belt) has been gradually increasing. Observational surveys have greatly expanded the inventory of Trans-Neptunian Objects (TNOs), which are distant icy bodies thought to be relics from the giant planet formation era. In the distant Kuiper Belt beyond 50~au, several striking features seem to challenge our previous understanding of the early Solar System: 1) a very large population of objects in distant mean-motion resonances with Neptune, 2) a substantial detached population that are not dynamically coupled with Neptune’s effects, and 3) the existence of three very-large perihelion objects, known as Sednoids. I will demonstrate in this talk, that a super-Earth-mass planet temporarily present in the Solar System (referred to as a ‘Rogue Planet’), is able to create all these structures in the distant Kuiper Belt. Such a planet would have formed in the giant planet region and gotten scattered to a highly-eccentric orbit with a few hundred au semimajor axis with a typical lifetime of
100 Myr. Additionally, when examining the past history of the three Sednoids, I surprisingly find that all their apsidal lines were tightly clustered at 200° exactly 4.5 Gyr ago. This “primordial orbital alignment”, if confirmed true, strongly argues for an initial event that imprinted this particular apsidal orientation on early detached TNO population, and the rogue planet model could potentially explain this new phenomenon.

Facilitator
-Name: Masamitsu Mori
Comment: English

===============May 10 Fri==============

Campus:Mitaka
Seminar:NAOJ Seminar
Regularly Scheduled/Sporadic:Regular
Date and time:May 10 Fri, 2024 15:30-16:30
Place:Zoom/Large Seminar Room (hybrid)

Speaker:Dr. Athira Menon
Affiliation:Institute of Astrophysics of the Canary Islands

Title:Towards solving an old stellar puzzle: the origin(s) and fate(s) of blue supergiants

Abstract: The origin and fate of observed B-type blue supergiants (BSGs), has been a long-standing puzzle in stellar astrophysics. The majority of these stars are observed to be single (with no detectable companion), and populate the end of the main sequence (MS) and the Hertzsprung gap on the HR diagram. However, models of stars that are born alone, have found limited success in simultaneously explaining the measured physical and chemical properties of BSGs, thereby indicating that a different evolutionary channel may dominate their creation. In this talk, I will present novel models of stars that are born from the mergers of binaries containing giant stars and MS companions. To compare our models, we newly analysed a large sample of early B-type supergiants in the Large Magellanic Cloud (LMC) and derived their surface properties. Unlike classical single-star models, merger-born stars sustain their BSG status throughout their core He-burning phase and quite easily populate the traditional Hertzsprung gap. We find that the largest group of the observed sample are likely only born from mergers, a smaller second group may contain both born-alone stars and merger-born stars and the minority are likely MS single stars. Although supernova SN 1987A is the most famous explosion of a BSG, the rate of 87A-like events is lower than the observed number of BSGs. I will close the talk with possibilities of other transients and remnants that may be the final outcomes of the deaths of BSGs.

Facilitator
-Name:Takuma Izumi

2024.4.29-2024.5.5


April 30 Tue 10:00-11:30
太陽系小天体セミナー (Solar System Minor Body Seminar)
Zoom


詳細は下記からご覧ください。

=============== April 30 Tue===============

キャンパス:三鷹
セミナー名:太陽系小天体セミナー (Solar System Minor Body Seminar)
定例・臨時の別:定例
日時: 4月 30日(火曜日)10時00分~11時30分
場所:zoom
講演者:藤井大地
所属: 平塚市博物館

世話人の連絡先
-名前:渡部潤一
備考:zoomでの参加