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