Mar. 22 Wed 11:00-12:00 NAOJ Seminar Zoom / Large Seminar Room(hybrid)
Mar. 22 Wed 14:30-15:30 ALMA-J seminar Zoom / ALMA building #102 (hybrid)
Mar. 22 Wed 15:30-17:00 NAOJ Science Colloquium Zoom / Instrument Development Bldg. 3 (hybrid)
Mar. 22 Wed 16:00-17:00 NAOJ Seminar Zoom / Large Seminar Room(hybrid)
詳細は下記からご覧ください。
=============== Mar 22 Wed ===============
Campus：Mitaka
Seminar：NAOJ Seminar
Regularly Scheduled/Sporadic：Sporadic
Date and time：2023 March 22, 11:00-12:00
Place： Zoom/Large Seminar Room(hybrid)
Speaker:Wei Cui
Affiliation：清華大学
Title：Galaxies in X-ray Perspective
Abstract：With advancement in technologies, which has led to a dramatic increase in observing capabilities in recent years, the studies of galaxies are becoming ever so detailedand the progress is rapid. On the other hand, it is increasingly clear what meets the eyes is, by no means, the entire picture. The outer region of a galaxy ecosystem, where the interplay between the accretion from large-scale structures and baryonic feedback processes originating in the galaxy might play a significant role, is hardly observable at present, depriving us of the important boundary conditions that are required to fully solve the puzzle of galaxy formation and evolution. Theory is far ahead of observation in this case, predicting the presence of X-ray-emitting hot gas in the circumgalacticmedium, which may contain a sufficient amountof baryons to explain why the baryon fraction of a typical galaxy (like the Milky Way) is far below the cosmic average. However, much of what goes into theoretical models is quite uncertain; the lack of relevant observations is severely impeding the progress of the field. In this talk, I will describe the theoretical scenarios and the unresolved issues, anddiscuss why a dedicated effort is needed to address the issues and what are required of such an effort.
Facilitator
-Name：Hori,Yasunori
=============== Mar. 22 Wed ===============
Campus：Mitaka,
Seminar：ALMA-J seminar
Regularly Scheduled/Sporadic： Every Wednesday
Date and time： March 22, 2023 (Wed), 14:30 – 15:30
Place： ALMA building #102 / Zoom (hybrid)
Speaker : Ryota Ikeda
Affiliation: SOKENDAI/NAOJ
Title: High-resolution ALMA study of cluster galaxies at z=1.46
Abstract: Understanding the formation of a bulge in massive galaxies is one of the main objectives of current extragalactic study. Since the fraction of massive elliptical galaxies is high in nearby galaxy clusters, observing star-forming phase of these progenitors is an effective approach for understanding when and how galaxies form a bulge. I present an ALMA study obtained from spatially resolved CO J=2–1 line (0.4” resolution) and 870 μm continuum (0.2” resolution) observations of 17 star-forming galaxies in a massive cluster at z = 1.46. We first measure the sizes of both CO J=2–1 line and 870 μm dust continuum emissions for nine CO emitters by modeling the visibilities. We find that the CO J=2–1 line emission is systematically extended than the dust continuum emission by a factor of ~3. The spatially resolved Kennicutt-Schmidt relation reveals that the central region of galaxies tends to have a shorter gas depletion timescale, i.e. a higher star formation efficiency (SFE), compared to the extended region. Our result suggests that star formation activities are concentrated in the central part of the extended gas reservoir, resulting in the formation of a bulge structure. We further conduct the kinematical modeling of CO J=2-1 line for 10 CO emitters. All of the CO emitters show flat rotation curve from 1-5 kpc, qualitatively suggesting that the bulge growth has already in progress in these cluster galaxies.
Finally, I will briefly introduce the CRISTAL Survey, an ALMA Cycle 8 LP, which will enable the first systematic studies of spatially resolved [CII] line and dust continuum emissions in star-forming galaxies at z=4-5.
Facilitator: Shun Ishii , Jorge Zavala
=============== Mar. 22 Wed ===============
Campus：Mitaka
Seminar：NAOJ Science Colloquium
Regularly Scheduled/Sporadic：Every Wednesday
Date and time：2023 March 22, 15:30-17:00
Place：zoom / Instrument Development Bldg. 3 (hybrid)
Speaker：Ohashi Nagayoshi
Affiliation：ASIAA
Title：Rotation in star and planet forming regions
Abstract：One of the remarkable properties of stars is the ubiquity of spinning motion, which can be found in any astrophysical objects in our Galaxy. The rotation period of the Sun is about one month and those of other stars vary a lot. In case of neutron stars they are as small as milli-seconds. Rotation is also commonly observed in dense cores, and it plays essential roles in star and planet formation, i.e., rotation is crucial to form protoplanetary disks around young stellar objects (YSOs) and also to drive outflows/jets. Nevertheless, rotation in dense cores has been studied less systematically than infall and outflow motions to date
In my presentation, I will review previous key works studying rotation in dense cores and try to summarize the latest understanding of how angular momentum transfers from outer parts to inner parts of dense cores based on my personal view. As a related topic, I will also discuss the latest observational results of embedded disks with an emphasis on the eDisk ALMA large program.
Facilitator
-Name：Akimasa Kataoka
-Comment：English
=============== Mar. 22 Wed ===============
Campus：Mitaka
Seminar：NAOJ Seminar
Regularly Scheduled/Sporadic：Sporadic
Date and time：2023 March 22, 16:00-17:00
Place： Zoom/Large Seminar Room(hybrid)
Speaker:Andy Sheinis
Affiliation：Canada France Hawaii Telescope
Title：Updates to the MaunakeaSpectroscopic Explorer
: Thousands of Fibers, Infinite Possibilities
Abstract：MSE is a massively multiplexed spectroscopic survey facility that willreplace the Canada-France-Hawaii-Telescope in the coming decade. This11-m plus telescope, with its 1.5 square degree field-of-view, willobserve 4,000 –20,000 astronomical targets in every pointing from 360nm through H-band at low/moderate resolution (R=3,000/7,000) and high (R=30,000). Piezo actuators position individual fibers in the field ofview to enable simultaneous full field coverage for both resolution
modes. MSE will unveil the composition and dynamics of the faint Universe and impact nearly every field of astrophysics across all spatial scales, from individual stars to the largest scale structures in the Universe, including (i) the ultimate Gaia follow-up facility for understanding the chemistry and dynamics of the distant Milky Way, including the outer disk and faint stellar halo at high spectral resolution (ii) galaxy formation and evolution at cosmic noon, (iii) derivation of the mass of the neutrino and insights into inflationary physics through a cosmological redshift survey that probes a large volume of the Universe with a high galaxy density. The instrument suite,
dedicated to large scale surveys, will enable MSE to collect a massive amount of data: equivalent to a full SDSS Legacy Survey every 7 weeks. We present an update to the major systems development for MSE along with the ongoing process of evaluating improvements to the baseline telescope
design. In addition, we present the plan to develop a Pathfinder instrument at CFHT to fast-track development of the MSE technology as well as provide a wide-field spectroscopic capability in the visible and NIR.
Facilitator
-Name：Hori,Yasunori