Zobrazeno 1 - 10
of 44
pro vyhledávání: '"Kimitake Hayasaki"'
Publikováno v:
The Astrophysical Journal, Vol 975, Iss 1, p 141 (2024)
We study the effect of irradiation from two accretion disks (minidisks) around respective black holes of stellar-to-intermediate masses in a circular binary on the spectrum of a circumbinary disk (CBD) surrounding them. We assume the CBD to be a stan
Externí odkaz:
https://doaj.org/article/2b16b7e9b8f846e2bf7cd3362545345d
Publikováno v:
The Astrophysical Journal, Vol 975, Iss 1, p 94 (2024)
We present a time-dependent, one-dimensional, magnetically driven disk wind model based on magnetohydrodynamic (MHD) equations, in the context of tidal disruption events (TDEs). We assume that the disk is geometrically thin, is gas pressure dominated
Externí odkaz:
https://doaj.org/article/14b703dcd5b24f6c9f4aa3b1bd1b0eb2
Publikováno v:
The Astrophysical Journal, Vol 958, Iss 1, p 52 (2023)
Circinus X-1 (Cir X-1) is a neutron star binary with an elliptical orbit of 16.6 days. The source is unique for its extreme youth, providing a key to understanding early binary evolution. However, its X-ray variability is too complex to reach a clear
Externí odkaz:
https://doaj.org/article/1528ce4f35fd4b4990fe18dec1ecaed8
Publikováno v:
The Astrophysical Journal, Vol 959, Iss 1, p 19 (2023)
Tidal disruption events (TDEs) provide a clue to the properties of a central supermassive black hole (SMBH) and an accretion disk around it, and to the stellar density and velocity distributions in the nuclear star cluster surrounding the SMBH. Devia
Externí odkaz:
https://doaj.org/article/7e247fb23e874c9f84de583922417e19
Autor:
Kimitake Hayasaki, Ryo Yamazaki
Publikováno v:
The Astrophysical Journal, Vol 954, Iss 1, p 5 (2023)
We study the evolution of a nonrelativistically expanding thin shell in radio-emitting tidal disruption events (TDEs) based on a one-dimensional spherically symmetric model considering the effect of both a time-dependent mass-loss rate of the disk wi
Externí odkaz:
https://doaj.org/article/76795234b0564f19a0c87a949607da93
Autor:
Prantik Nandi, Arghajit Jana, Arka Chatterjee, Neeraj Kumari, Gaurava K. Jaisawal, Claudio Ricci, Sachindra Naik, Kimitake Hayasaki
Publikováno v:
Jana, A, Kumari, N, Nandi, P, Naik, S, Chatterjee, A, Jaisawal, G K, Hayasaki, K & Ricci, C 2021, ' Broad-band X-ray observations of the 2018 outburst of the changing-look active galactic nucleus NGC 1566 ', Monthly Notices of the Royal Astronomical Society, vol. 507, no. 1, pp. 687-703 . https://doi.org/10.1093/mnras/stab2155
We study the nature of the changing-look Active Galactic Nucleus NGC 1566 during its June 2018 outburst. During the outburst, the X-ray intensity of the source rises up to ~25-30 times compared to its quiescent state intensity. We perform timing and
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ba6719aabcbae4addb2148fb113af9b3
Autor:
Peter G. Jonker, Kimitake Hayasaki
Publikováno v:
The Astrophysical Journal, 921, 1-9
The Astrophysical Journal, 921, 1, pp. 1-9
The Astrophysical Journal, 921, 1, pp. 1-9
We propose a model to explain the time delay between the peak of the optical and X-ray luminosity, \dt hereafter, in UV/optically-selected tidal disruption events (TDEs). The following picture explains the observed \dt in several TDEs as a consequenc
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::90162c464279e81e25accd59b8397ad7
Autor:
Gwanwoo Park, Kimitake Hayasaki
We study the mass fallback rate of tidally disrupted stars on marginally bound and unbound orbits around a supermassive black hole (SMBH) by performing three-dimensional smoothed particle hydrodynamic (SPH) simulations with three key parameters: the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::23b320cb78f5e9ccb30184fa099e961f
Autor:
Kimitake Hayasaki
Publikováno v:
Nature Astronomy. 5:436-437
Tidal disruption events are an excellent probe for supermassive black holes in distant inactive galaxies because they show bright multi-wavelength flares lasting several months to years. AT2019dsg presents the first potential association with neutrin
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e4f58a82e0940d48b0616f1181269e68
https://doi.org/10.1038/s41550-021-01309-z
https://doi.org/10.1038/s41550-021-01309-z
Publikováno v:
Publications of the Astronomical Society of Japan. 62:1351-1360
If the activity of active galactic nuclei (AGNs) is predominantly induced by major galaxy mergers, then a significant fraction of AGNs should harbor binary massive black holes in their centers. We study the mass function of binary massive black holes
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::6f734b1fec74ea9acacb38355aa608be
https://doi.org/10.1093/pasj/62.5.1351
https://doi.org/10.1093/pasj/62.5.1351