2023.5.15-2023.5.21


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


May  17  Wed   10:30-12:00   SOKENDAI Colloquium   Zoom / the large seminar room (hybrid)


May  17  Wed   14:30-15:30    ALMA-J seminar  Zoom / ALMA building #102 (hybrid)


May  17  Wed   15:30-17:00    NAOJ Science Colloquium Zoom / the large seminar room (hybrid)


May  19  Fri  16:00-17:00    NAOJ Seminar         Zoom / the large seminar room (hybrid)


詳細は下記からご覧ください。

=============== May 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:5月16日(火曜日)10時00分~11時30分
場所:zoom

世話人の連絡先
 名前:渡部潤一

=============== May 17  Wed===============

Campus:Mitaka
Seminar:SOKENDAI Colloquium
Regularly Scheduled/Sporadic:Regular
Date and time:May 17, 2023 10:30-12:00
Place:Large Seminar Room in Subaru Building and Zoom

Speaker: Yoshihiro Naito
Affiliation: SOKENDAI 2nd year (M2) (Supervisor: Hirohisa Hara, Ryoko Ishikawa, Joten Okamoto)
Title: Spectroscopic study of the source region for fast solar wind acceleration in coronal holes(+ Review of Weberg+ 2018)

Speaker : Shun Ishigami
Affiliation: SOKENDAI 3rd year (D1) (Supervisor: Hirohisa Hara, Yukio Katsukawa, Masahito Kubo)
Title: Review: Observation and Modeling of High-temperature Solar Active Region Emission during the High-resolution Coronal Imager Flight of 2018 May 29 (Warren et al., 2020)

Facilitator
-Name:Matsuda, Graduate Student Affairs Unit

=============== May 17  Wed===============

Campus:Mitaka
Seminar:ALMA-J seminar
Regularly Scheduled/Sporadic: Every Wednesday
Date and time: May 17th, 2023 (Wed), 14:30 – 15:30
Place: ALMA building #102 / Zoom (hybrid)

Speaker: Marta Frias Castillo
Affiliation: Leiden University
Title: Cold gas reservoirs in high-redshift galaxies uncovered by the JVLA and NOEMA
Abstract: In order to obtain a more complete understanding of galaxy formation, it is critical to trace the evolution of the direct fuel for star formation, the molecular gas content. Studies of cold molecular gas reservoirs, traced by low-J CO line emission, have exploded in recent years thanks to state-of the-art sub-millimeter interferometers such as ALMA and the JVLA. Despite enormous progress, these studies have been almost entirely based on detections of the bright mid/high-J CO transitions, which have been shown to give a biased and incomplete view of the total cold molecular gas content in galaxies. Detecting the ground-state CO(J=1-0) transition remains a challenge due to its intrinsic faintness compared to higher-J CO lines for the typical excitation conditions in high-z galaxies. In this talk I will discuss the molecular gas reservoirs uncovered by low-J CO line emission in two recent surveys targeting a sample of high-redshift star-forming galaxies and lensed quasars (QSOs). The observations we have obtained allow us to explore the gas excitation conditions of star-forming galaxies and the possible effects of AGN feedback upon the gas reservoirs of QSO-host galaxies.

Facilitator: Toshiki Saito, Andrea Silva

=============== May 17  Wed===============

Campus:Mitaka
Seminar:NAOJ Science Colloquium
Regularly Scheduled/Sporadic:Every Wednesday
Date and time:2023 May 17, 15:30-17:00

Speaker:Kanji Mori
Affiliation:NAOJ
Title:Core-collapse Supernovae as Laboratories for Axion-like Particles
Abstract:Axion-like particles (ALPs) are a class of hypothetical
pseudoscalar particles which feebly interact with ordinary matter. The
hot plasma in core-collapse supernovae is a possible laboratory to
explore physics beyond the standard model including ALPs. Once produced
in a supernova, a part of the ALPs can be absorbed by the supernova
matter and affect energy transfer. We recently developed two-dimensional
supernova models including the effects of the production and the
absorption of ALPs that couple with photons. It is found that the
additional heating induced by ALPs can enhance the explosion energy; for
moderate ALP-photon coupling, we find explosion energies ~0.610^51 erg compared to our reference model without ALPs of ~0.410^51 erg. Our
findings also indicate that when the coupling constant is sufficiently
high, the neutrino luminosities and mean energies are decreased because
of the additional cooling of the proto-neutron star. The gravitational
wave strain is also reduced because the mass accretion on the
proto-neutron star is suppressed.

Facilitator
-Name:Hiroki Nagakura
-Comment:English

=============== May 19  Fri===============

Campus:Mitaka
Seminar:NAOJ Seminar
Regularly Scheduled/Sporadic:Regularly Scheduled
Date and time:2023 May 19, 16:00-17:00
Place: Zoom/Large Seminar Room(hybrid)

Speaker:Rosemary WYSE
Affiliation: Johns Hopkins University
Title:The Old are Rich: Implications of the Old, Metal-Rich Milky Way
Abstract:TheinnerregionsoftheMilkyWaycontainold,metal-richstars,
consistentwithhavingformedinanearlystarburstwithinadeep
potentialwell.Indeed,mostGalacticstarsolderthan8Gyraremore
metal-richthan[Fe/H]~-0.5.SimulationsofMilkyWay-likegalaxiesin
standardColdDarkMatterdominatedcosmologicalmodelsfailtoreach
suchhighmetallicitiesatearlyepochs,plausiblyreflectingthe
low-masssub-structuresinwhichtheancientstarsform.Iwillquantify
thiscomparisonbetweenobservationsandpredictions,usingagesand
metallicitiesforstarsinourGalaxyandpublicdatasetsfromarange
ofsimulationsofMilkyWaymassgalaxies.Iwilltheninterpretthe
resultsinthecontextofotherindicationsoftherapidgrowthofMilky
Way-likegalaxiesandtheirassociateddarkmatterhaloes,andresulting
tensionswiththepredictionsofCDMongalacticscales.

Facilitator
-Name:Ozaki, Shinobu