カテゴリー: Solar and Space Plasma (SSP) Seminar

January 16 Tue 10:00-11:30 太陽系小天体セミナー
Zoom

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January 17 Wed 10:30-12:00 SOKENDAI Colloquium
Large Seminar Room in Subaru Building and Zoom (hybrid)

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January 17 Wed 14:30-15:30 ALMA-J seminar
Room 102 in the ALMA Building and Zoom (hybrid)

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January 17 Wed 15:30-16:30 NAOJ Science Colloquium
Zoom

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January 18 Thu 10:00-12:00 SOKENDAI Doctoral Thesis Dissertation review
Lecture Room and Zoom (hybrid)

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January 18 Thu 15:30-17:30 SOKENDAI Doctoral Thesis Dissertation review
Lecture Room and Zoom (hybrid)

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January 19 Fri 10:30-12:00 Solar and Space Plasma Seminar
Central Building (North) / 310 and Zoom (hybrid)

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詳細は下記からご覧ください。

=============== January 16 Tue ===============

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：1月16日（火曜日）10時00分～11時30分
場所：zoom
講演者：宇田豊和
所属：Aiharasoft
タイトル：ハワイ・マウナケア星空ライブからの流星自動検出システム概要
Abstract：ハワイ・マウナケア星空ライブからの流れ星自動検出システムを構築しました。
2022年1月より、大きな流れ星を検出すると、Xでポストする運用を行っています。
今回の発表では、このシステムの概要、流れ星の検出アルゴリズム概要、
ふたご座流星群などの検出状況、現状の問題点、課題についてご説明します。

世話人の連絡先
　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

=============== January 17 Wed ===============

Campus：Mitaka
Seminar：SOKENDAI Colloquium
Regularly Scheduled/Sporadic：Regular
Date and time：January 17, 2024 10:30-12:00
Place：Large Seminar Room in Subaru Building and Zoom

Speaker: Kazuki Watanabe
Affiliation: SOKENDAI 1st year (M1) (Supervisor: Yoshinori Uzawa, Takafumi Kojima, Tai Oshima)
Title: Development of a sub-THz MKID Camera for Deep Space Observation

Speaker: Miho Tan
Affiliation: SOKENDAI 1st year (M1) (Supervisor: Mami Machida, Tomoya Takiwaki, Kazunari Iwasaki)
Title: Effect of an optical star wind on SS433’s jet propagation

Facilitator
-Name：Matsuda, Graduate Student Affairs Unit

=============== January 17 Wed===============

Campus: Mitaka
Seminar: ALMA-J seminar
Date and time: January 17 (Wed) 14:30-15:30
Place: hybrid (Room 102 in the ALMA building and Zoom)

1st speaker: Yuzuki Nagashima
Affiliation: Fukushima university / NAOJ
Title: High-precision SFR mapping of the nearby galaxy NGC 1068 using ALMA 100 GHz continuum and HST Paα line and the effect of DIG contamination.

Abstract:
The star formation rate (SFR) is an important indicator in the context of galaxy evolution. However, it is not easy to accurately measure the SFR in external galaxies. For example, the most common method is to use radiation from the HII region, but the to assume temperature of the HII region and the contribution of other radiation sources make it difficult to accurately estimate the SFR. Furthermore, in the infrared and optical wavelength bands, the effect of dust extinction is significant and needs to be corrected. Therefore, it is important to observe in the millimeter and sub-millimeter wavelength bands with ALMA, which are not affected to dust extinction, especially, which has high sensitivity and high resolution. In recent years, with the improvement of data accuracy, a method to isolate, identify, and extract whether the source of ionized gas is from star formation or not is being established. By identifying and subtracting stronger ionization sources (e.g., AGN origin) and weaker (Diffuse Ionized Gas; DIG origin) than star formation sources, SFRs that are less contradiction with SFRs derived from multiple tracers have been reported (e.g., Michiyama et al. 2020). Michiyama et al. 2020).
We produced a precise SFR map for the nearby galaxy NGC 1068 by comparing the two different ionized gas tracers, free-free emission and hydrogen recombination line the Paα, and by considering the effect of DIG.
In this talk, I will introduce how to make an accurate SFR map and the result.
In addition, I will focus on the DIG correction.

2nd speaker: Mahoshi Sawamura
Affiliation: University of Tokyo / NAOJ
Title: No galaxy-scale [CII] outflow detected in a z=6.72 red quasar with ALMA

Abstruct:
It has been claimed that active galactic nucleus (AGN)-driven massive outflows, which would happen during a transition phase from an obscured dusty quasar to a normal blue quasar, are the key physical process in driving the co-evolution of galaxies and supermassive black holes (SMBHs). Partially dust-obscured red quasars are thought to be the immediate phase of this transition. However, while many blue quasars at z = 6~7 have been found in recent years, it is still hard to identify red quasars at that epoch due to their apparent faintness. Deep, wide-area surveys and subsequent multi-wavelength follow-up observations are thus required to identify such red objects and test the above evolutionary scenario. Here we report our ALMA cycle 7 observations of the z = 6.72 red quasar HSC 120505.09−000027.9 (J1205−0000). This is one of the highest redshift (z > 6) red quasars originally identified by our deep Subaru Hyper Suprime-Cam (HSC) survey. It is apparently faint, but is intrinsically as luminous as −24.4 mag at rest-UV and hosts a massive BH of 2.2 × 10^9 Msun. It is also known to be N V and C IV BAL object, indicating the existence of nuclear outflows. We successfully detected both the [CII] 158 μm line and the underlying rest-FIR continuum emission (resolution ~0.6″, 1σ ~ 0.1 mJy/beam at dV = 75 km/s). The continuum is very bright, with the estimated luminosity of 2.3 × 10^12 Lsun (or equivalently SFR ~ 485 Msun/yr), which indicates that the host galaxy of this red quasar is indeed a starburst system. However, the detailed analysis of the visibility data suggests that the bulk of this IR emission originates from a spatially unresolved compact component, likely the AGN itself. Hence the actual SFR could be much smaller. Regarding the AGN feedback, our observations do not conclusively assert the presence of [CⅡ] outflows. One possible interpretation of this is that the spatial scale of the outflow is not large enough to reach the host galaxy. However, we propose that this red quasar is indeed in a key evolutionary phase of AGN feedback. We will also discuss possible future observations to explore the existence of this wing component.

=============== January 17 Wed==============

Campus: Mitaka
Seminar: NAOJ Science Colloquium
Date and time: 2023 Jan. 17 (Wed.), 15:30-16:30
Place: Zoom

Speaker: Bruce Gendre
Affiliation: Australian National University
Title: Progenitors of ultra-long gamma-ray bursts: an ultra-long and ultra-slow developing story
Abstract:
Gamma-ray bursts are fantastic explosions seen at cosmological distances, and one of the most extreme high energy events of the Universe. Because of their distance, understanding the phenomenon at play is challenging. In this seminar, I will review the GRB phenomenon, what we already know about the progenitor of those events, focusing on the most unknown kind of event, the ultra-long ones, and how we use the current technology for improving our knowledge.

Facilitator
-Name: Maria Giovanna Dainotti
Comment: English

=============== January 18 Thu==============

Campus：Mitaka
Seminar：SOKENDAI Doctoral Thesis Dissertation review
　　　　　総研大博士学位論文予備審査会
Regularly Scheduled/Sporadic：Sporadic
Date and time：January 18, 2024 10:00-12:00
Place ：Lecture Room and Zoom

Speaker：Raiga Kashiwagi
Title：Instability and Evolution of Shocked Clouds Formed by Collisions between Filamentary Molecular Clouds

Facilitator
-Name：Nozomu Tominaga, Hideyuki Kobayashi, Kaya Kitabayashi (Graduate Student Affairs Unit)

Comment:
https://guas-astronomy.jp/CampusLife/doctor_report.html

=============== January 18 Thu==============

Campus：Mitaka
Seminar：SOKENDAI Doctoral Thesis Dissertation review
　　　　　総研大博士学位論文予備審査会
Regularly Scheduled/Sporadic：Sporadic
Date and time：January 18, 2024 15:30-17:30
Place ：Lecture Room and Zoom

Speaker：Rikuto Omae
Title：Probing the Magnetic Fields of Distant Galaxies to Unravel the Evolution of Galactic Magnetic Fields

Facilitator
-Name：Nozomu Tominaga, Hideyuki Kobayashi, Kaya Kitabayashi (Graduate Student Affairs Unit)

Comment:
https://guas-astronomy.jp/CampusLife/doctor_report.html

=============== January 19 Fri==============

Campus： Mitaka
Seminar： Solar and Space Plasma Seminar
Regularly Scheduled/Sporadic： Sporadic
Date and time：19th January (Fri), 10:30-12:00
Place： hybrid; Central Building (North) / 310 and Zoom

Speaker：Dr. Ryoko Ishikawa
Affiliation：NAOJ
Title：3D mapping of the magnetic field in the whole atmosphere of an active region plage with the CLASP2.1 sounding rocket experiment
Abstract：Probing the magnetic field throughout the solar atmosphere is critically important for understanding the energy transfer from the photosphere to the corona. However, there is an overwhelming lack of empirical information on the magnetic field in the upper chromosphere and the layers above, where the magnetic pressure dominates the gas pressure (β < 1). To this end, a novel approach is to measure and model the polarization of magnetically-sensitive ultraviolet (UV) spectral lines. The series of sounding rocket experiments CLASP (2015), CLASP2 (2019) and CLASP2.1 (2021) have demonstrated that UV spectro-polarimetry is indeed a suitable diagnostic tool for investigating the magnetic fields in the whole solar chromosphere. On October 8, 2021, CLASP2.1 measured the Stokes profiles of the 280 nm spectral region at 16 consecutive slit positions covering a two-dimensional field of view in an active region plage. This near-UV spectral region contains the resonance lines of Mn I (which provide information on the lower chromosphere) and the Mg II h & k lines (which provide information on the middle and upper chromosphere). Combined with coordinated observations with the Solar Optical Telescope (SOT) aboard the Hinode satellite, we obtained a line-of-sight magnetogram covering a sunspot penumbra and a plage (moss) region at multiple heights from the photosphere to the top chromosphere. The 3D mapping enables how the magnetic patches expand with height and how much magnetic flux reaches higher in the chromosphere. The obtained magnetogram is compared with the high-resolution images recorded by IRIS and SDO/AIA, revealing the connectivity between the magnetic structure in the chromosphere and the coronal loops.

Facilitator
-Name：Akiko Tei

Comment：English

Oct 10 Tue 　　　 10:00-11:30 　　　太陽系小天体セミナー Zoom

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Oct 11 Wed 　　　13:30-15:00 Solar and Space Plasma Seminar 　 hybrid; Subaru Building / Insei Seminar Room or Zoom

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Oct 11 Wed 　　　14:00-15:00 　 Tea Talk 輪講室（＋Zoom）

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Oct 11 Wed 　　　14:30-15:30 　　 ALMA-J seminar hybrid (ROOM102 in ALMA building and ZOOM)

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Oct 11 Wed 　　　15:30-16:30 　　 NAOJ Science Colloquium Zoom / the large seminar room (hybrid)

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Oct 13 Fri 　 16:00-17:00 NAOJ Seminar zoom/ Large seminar room in Subaru Building

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詳細は以下をご覧下さい。

=============== October　10　Tue===============

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：10月10日（火曜日）10時00分～11時30分
場所：zoom
講演者：秋澤宏樹

Abstract：『COMETS III』より、著者による先行公開されている２つの章、
「彗星大気の化学」
https://www.research.ed.ac.uk/en/publications/chemistry-of-comet-atmospheres
「遠隔観測による彗星核の物理・表面特性」
https://arxiv.org/abs/2304.09309
の内容を紹介したいと思います。

世話人の連絡先
　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

=============== October　11　Wed===============

Campus： Mitaka
Seminar： Solar and Space Plasma Seminar
Regularly Scheduled/Sporadic： Scheduled
Date and time：11th Oct (Wed), 13:30-15:00
Place： hybrid; Subaru Building / Insei Seminar Room or Zoom
Speaker： Stanislav Gunar
Affiliation：Astronomical Institute of the Czech Academy of Sciences
Title：What is important for robust inversions of spectroscopic observations of chromospheric and coronal structures?
Abstract：In this presentation, we will discuss what is hidden behind the term “robust spectroscopic inversions” and what we need to achieve them. We will focus on the use of UV spectral data, such as the Lyman line series and the Mg II h&k lines.

There are several necessary ingredients needed to produce high-fidelity spectroscopic inversions. The first is high-resolution multi-wavelength observations. The second are realistic radiative transfer models encompassing dominant processes forming the observed spectra. The third component is sophisticated inversion methods that allow us to find a realistic fit between the observed and synthetic spectra. And there is another necessary component – a good understanding of all important boundary conditions.

We will demonstrate the importance of boundary conditions on the example of the so-called incident radiation. This is the radiation coming from the solar surface, which illuminates chromospheric and coronal structures, such as prominences or spicules. We will show that variations in this boundary condition have a strong impact on the shape and intensity of Lyman lines and the Mg II h&k lines. This impact is then responsible for significantly different outcomes of spectroscopic inversions.

Facilitator
Name：Takayoshi oba
Comment：in English

=============== October　11　Wed===============

キャンパス：三鷹　野辺山 水沢 岡山 ハワイ
セミナー名：Tea Talk
定例・臨時の別：臨時
日時：10/11（水）14：00～15：00
場所：輪講室（＋Zoom）
講演者：渡部　潤一
所属：天文情報センター
タイトル：APRIM2023の顚末記

世話人の名前：藤田登起子

=============== October　11　Wed===============

Campus: Mitaka
Seminar: ALMA-J seminar
Date and time: Oct 11th (Wed) 14:30-15:30
Place: hybrid (ROOM102 in ALMA building and ZOOM)
Speaker: Tetsu Kitayama
Affiliation: Toho University
Title: High-resolution measurements of the Sunyaev-Zel’dovich effect toward galaxy clusters
Abstract:
The Sunyaev-Zel’dovich effect (SZE) provides a unique probe of cosmic plasma up to high redshifts. We first review briefly the progress of high-resolution SZE observations over the past two decades. We then present the measurements made by the Atacama Large Millimeter/submillimeter Array (ALMA); we have obtained SZE images toward four galaxy clusters with 5″ resolution, while retaining extended signals out to 40″. We also discuss implications of these results on the evolution of galaxy clusters as well as prospects for further SZE measurements.

=============== October　11　Wed===============

Campus：Mitaka
Seminar：NAOJ Science Colloquium
Regularly Scheduled/Sporadic：Every Wednesday Date and time：2023 Oct. 11, 15:30-16:30
Place：Zoom / the large seminar room (hybrid)

Speaker：Daichi Kashino
Affiliation：NAOJ
Title：Witnessing Galaxies Reionizing the Intergalactic Medium with JWST
Abstract：
Cosmic reionization is the last major phase transition of the universe, occurring in the first billion years after the Big Bang.
Understanding this process is one of the pivotal goals in modern astrophysics. The commissioning of JWST heralded a new era in investigating the roles of galaxies in reionizing the intergalactic medium, thanks to its unprecedented high sensitivity and dispersing power in near infrared.

In the presentation, I will present early results from our ongoing EIGER (Emission-line galaxies and Intergalactic Gas in the Epoch of
Reionization) survey, a JWST/NIRCam WFSS campaign in the fields of luminous z>6 quasars. The existence of these background quasars enables us to determine the ionization condition along their lines of sight from analysis of the high signal-to-noise quasar spectra. The primary objective of the project is to characterize the cross correlation between galaxies (as pinpointed by JWST) and the IGM conditions during the tail end of the epoch of reionization. In the first quasar field, we confirmed roughly 150 [OIII]5008-emitting galaxies over the redshift range of z=5.3–6.9. Through analyzing the distribution of these galaxies and the transmission spectrum of this corresponding quasar, we identified individual spatial coincidence between the groups of galaxies and highly ionized regions, as well as a mean excess IGM transmission in both Lyman-alpha and Lyman-beta around ~6 cMpc away from the galaxies at z~6. This is interpreted as direct evidence of local reionization by galaxies — indicating that we are witnessing galaxies reionizing the surrounding IGM. I may also showcase further preliminary results from other quasar fields currently being analyzed.

Facilitator
Name：Haruka Kusakabe
Comment：English

=============== October　13　Fri===============

Campus：Mitaka
Seminar：NAOJ Seminar
Regularly Scheduled/Sporadic：Regularly Scheduled Date and time：2023 Oct 13, 16:00-17:00
Place：zoom/ Large seminar room in Subaru Building

Speaker: Cristian Eduard Rusu, PhD
Affiliation: Axelspace Corporation
Title: Opportunities and Challenges for Space Observations with Commercial Satellites
Abstract：Over the past decade, the number of satellites launched into orbit for commercial
purposes has increased exponentially. Nonetheless, these have had virtually no usage for
astronomical observations, due to the still prohibitive cost of launching large mirrors and
achieving scientific-level tolerances. In recent years however, governments as well as private
companies have become interested in Space Situation Awareness, or gaining insights from
optical monitoring from space of artificial satellites and space debris as faint as the 14th magnitude.
This renewed interest in space observations has the potential of reducing the cost of dedicated
astronomical satellites and bringing them within the reach of commercial companies.
I will explore these topics as experienced from the point of view of Axelspace, a Japanese commercial
satellite manufacturer and provider of satellite imagery.

Facilitator
-Name：Moriya, Takashi