Masato I.N. KOBAYASHI / Publications

[5] "Nature of supersonic turbulence and density distribution function in the multiphase interstellar medium"
M.I.N.Kobayashi, T.Inoue, K.Tomida, K.Iwasaki, and H.Nakatsugawa
[arXiv: 2203.00699, ADS, ApJ
Summary: We perform molecular cloud formation simulation resolving the thermal instability from the Warm Neutral Medium (WNM), and investigate the turbulent mode fraction between the solenoidal mode and compressive mode. We found that solenoidal mode accounts for more than 80 percent of the turbulence power in molecular clouds, which indicates that galactic-scale compressive motions do not always trigger active star formation. We also analyzed the density probability distribution function (PDF) with multiple thermal states. We found that the the shape of the density PDF of the WNM component is well explained by the isothermal turbulent theory, wherease the density PDF of the Cold Neutral Medium (CNM) coponent alone shows a narrower width than the isothermal turbulent theory expects. These difference suggest that the strong turbulence on the cloud scale drives the WNM density variation and the relative motion between the CNM clumps, but the CNM density PDF is more controlled by the weak turbulence within each CNM clump.

[4] "Bimodal Behavior and Convergence Requirement in Macroscopic Properties of the Multiphase Interstellar Medium Formed by Atomic Converging Flows"
M.I.N.Kobayashi, T.Inoue, S.Inutsuka, K.Tomida, K.Iwasaki, and K.E.I.Tanaka
[arXiv: 2010.12368, ADS, ApJ]
Summary: We systematically perform atomic converging flow simulations to investigate the early phase of molecular cloud formation by varying the pre-shock warn neutral medium state, especially the amplitude of the density inhomogeneity. We found that, when the amplitude is >10%, the shock-compressed layer becomes turbulent-dominated and the mass fraction of the cold neutral medium remains about 50 %. When the amplitude is <10%, the layer is supported by the thermal and turbulent pressure equally and the mass fraction of the cold neutral medium is increased up to 70%. We also propose an effective equation of state that approximate the multiphase gas as one-phase medium.

[3] "Star Formation Induced by Cloud-Cloud Collisions and Galactic Giant Molecular Cloud Evolution"
M.I.N.Kobayashi, H.Kobayashi, S.Inutsuka, and Y.Fukui
[arXiv: 1708.07952, ADS, PASJ]
Summary: In addition to Kobayashi et al., 2017, we introduce triggered star formation by cloud-cloud collisions and how this process impacts the GMC mass function evolution. We found that triggered star formation destroy parental clouds thus it suppresses massive GMC populations but it does not significantly alter the GMC mass function shape. We also found that this triggered star formation may amount a few 10 percent of total galactic star formation.

[2] "Evolutionary Description of Giant Molecular Cloud Mass Functions on Galactic Disks"
M.I.N.Kobayashi, S.Inutsuka, H.Kobayashi, and K.Hasegawa
[arXiv: 1701.03781, ADS, ApJ]
Summary: We develop a time-evolution equation for giant molecular cloud mass functions on galactic scales. This is governed by the combination of cloud formation from magnetized warm interstellar medium through multiple episodes of supersonic compression, cloud dispersal due to stellar feedback from massive stars born within those clouds, and cloud-cloud collisions. Our results indicate that upcoming large radio surveys are capable of constraining the giant molecular cloud formation and dispersal timescales and the gas resurrecting factor.

[1] "Can we use Weak Lensing to Measure Total Mass Profiles of Galaxies on 20 kiloparsec Scales?"
M.I.N.Kobayashi, A.Leauthaud, S.More, N.Okabe, C.Laigle, J.Rhodes, and T.T.Takeuchi
[arXiv: 1502.06604, ADS, MNRAS]
Summary: This work explores the possibility of a weak gravitaional galaxy-galaxy lensing analysis on very small scales (e.g. about 20 kpc in the transeverse distance from lens galaxies) to probe the innermost galaxy/halo total mass profiles. To do this, we investigate the data from the COSMOS field taken by Hubble Space Telescope ACS and estimate the predicted signal-to-noise ratio for future surveys (e.g. Euclid and WFIRST). We explore and adress the potential challenging difficulties for a weak lensing analysis on such scales in details.

[17] "A Giant Molecular Cloud Catalog in the Molecular Disk of the Elliptical Galaxy NGC 5128 (Centaurus A)"
Rie E. Miura, Daniel Espada, Akihiko Hirota, ... M.I.N.Kobayashi, ...
arXiv: 2104.12442, ADS

[16] "Revealing the diverse magnetic field morphologies in Taurus dense cores with sensitive sub-millimeter polarimetry"
Eswaraiah Chakali, Di Li, Ray S. Furuya, ... M.I.N.Kobayashi, ...
arXiv: 2103.02219, ApJ

[15] "ALMA Observations of Giant Molecular Clouds in M33 III: Spatially Resolved Features of the Star-Formation Inactive Million-solar-mass Cloud"
Hiroshi Kondo, Kazuki Tokuda, Kazuyuki Muraoka, ... M.I.N.Kobayashi, ...
arXiv: 2103.01610, ADS, ApJ

[14] "Dust polarized emission observations of NGC 6334. BISTRO reveals the details of the complex but organized magnetic field structure of the high-mass star-forming hub-filament network"
Doris Arzoumanian, Ray S. Furuya, Tetsuo Hasegawa, ... M.I.N.Kobayashi, ...

[13] "Observations of Magnetic Fields Surrounding LkHα 101 Taken by the BISTRO Survey with JCMT-POL-2"
Nguyen Bich Ngoc,Pham Ngoc Diep, Harriet Parsons, ... M.I.N.Kobayashi, ...
arXiv: 2012.04297

[12] "CO Multi-line Imaging of Nearby Galaxies (COMING). IX. 12CO(J=2-1)/12CO(J=1-0) line ratio on kiloparsec scales"
Yoshiyuki Yajima, Kazuo Sorai, ... M.I.N.Kobayashi, ...
arXiv: 2012.08523, ADS

[11] "CHIMPS2: Survey description and 12CO emission in the Galactic Centre"
David J. Eden, Toby J.T. Moore, ... M.I.N.Kobayashi, ...
arXiv: 2009.05073, ADS

[10] "The JCMT BISTRO Survey: Magnetic fields associated with a network of filaments in NGC 1333"
Yasuo Doi, Testuo Hasegawa, ... M.I.N.Kobayashi, ...
arXiv: 2007.00176, ADS, ApJ

[9] "Systematic Variations of CO J=2-1/1-0 Ratio in The Barred Spiral Galaxy M83"
Jin Koda, Tsuyoshi Sawada, ... M.I.N.Kobayashi, ...
arXiv: 2001.11043 ADS, ApJ

[8] "The JCMT BISTRO Survey: The Magnetic Field of the Barnard 1 Star-Forming Region"
Simon Coude, Pierre Bastien, ... M.I.N.Kobayashi, ...
arXiv: 1902.07221 ADS,

[7] "The JCMT BISTRO Survey: The Magnetic Field In The Starless Core rho Ophiuchus C"
Junhao Liu, Keping Qiu, ... M.I.N.Kobayashi, ...
arXiv: 1902.07734, ADS,

[6] "CO Multi-line Imaging of Nearby Galaxies (COMING): VI. Radial variations in star formation efficiency"
Kazuyuki Muraoka, Kazuo Sorai, ... M.I.N.Kobayashi, ...
arXiv: 1901.11197, ADS,

[5] "JCMT BISTRO survey: Magnetic Fields within the Hub-Filament Structure in IC 5146"
Jia-Wei Wang, Shih-Ping Lai, ... M.I.N.Kobayashi, ...
arXiv: 1812.05818, ADS,

[4] "First observations of the magnetic field inside the Pillars of Creation: Results from the BISTRO survey"
Kate Pattle, ... the JCMT BISTRO Survey Team
arXiv: 1805.11554, ADS,

[3] "Stellar mass dependence of the 21-cm signal around the first star and its impact on the global signal"
Toshiyuki Tanaka, Kenji Hasegawa, Hidenobu Yajima, M.I.N.Kobayashi, Naoshi Sugiyama
arXiv: 1805.07947, ADS,

[2] "Magnetic Fields Towards OPHIUCHUS-B Derived From SCUBA-2 Polarization Measurements"
Archana Soam, ... M.I.N.Kobayashi, ...
arXiv: 1805.06131, ADS,

[1] "A First Look at BISTRO Observations of The rho Oph-A core"
Jungmi Kwon, ... M.I.N.Kobayashi, ...
arXiv: 1804.09313, ADS,

[1] "Star Formation Processes along with Time Evolution of Giant Molecular Cloud Mass Functions"
M.I.N.Kobayashi
The Astronomical Herald: vol. Sep 2018

[6] "Time evolution of giant molecular cloud mass functions with cloud-cloud collisions and gas resurrection in various environments"
M.I.N.Kobayashi, S-i.Inutsuka, H.Kobayashi, K.Hasegawa
ADS, Memorie della Societa Astronomica Italiana

[5] "Evolutionary Picture for the Mass Functions of Giant Molecular Clouds in Various Galactic Environment"
M.I.N.Kobayashi, S-i.Inutsuka, H.Kobayashi, K.Hasegawa
ADS

[4] "Time Evolution of the Giant Molecular Cloud Mass Functions across Galactic Disks"
M.I.N.Kobayashi, S-i.Inutsuka, H.Kobayashi, K.Hasegawa
ADS, Cambridge University Press

[3] "The Evolution of Giant Molecular Cloud Mass Function due to Cloud-Cloud Collisions"
M.I.N.Kobayashi, S-i.Inutsuka, H.Kobayashi, K.Hasegawa
ADS, EDP Sciences

[2] "The Formation and Destruction of Molecular Clouds and Galactic Star Formation"
S-i.Inutsuka, T.Inoue, K.Iwasaki, T.Hosokawa, M.I.N.Kobayashi
ADS, Cambridge University Press,

[1] "Baryonic Tully-Fisher relation and star formation rate"
M.I.N.Kobayashi and T.T.Takeuchi
ADS, PoS