コロキウム要旨 / Colloquium ABSTRACTS

Dr. Hiddo Algera (Hiroshima University/NAOJ)

TBD

F608

TBD

Dr. Alvina Y. L. On (National Center for Theoretical Science)

TBD

F608

TBD

Dr. Jennifer Y. H. Chan (Canadian Institute for Theoretical Astrophysics)

TBD

F313

TBD

Ms. Anastasiia Omeliukh (Ruhr University Bochum)

TBD

F608

TBD

Dr. Garaldi Enrico (IFPU/Osaka University)

TBD

F608

TBD

Prof. Shinsuke Takasao (Osaka University)

TBD

F608

TBD

Prof. emeritus Hideaki Takabe (Osaka University)

TBD

F608

TBD

Dr. Ryota Tomaru (Osaka University)

Accretion disk winds from X-ray binaries: Tests for those driving mechanisms and motivation of a physical model for AGN feedback

F608

Accretion disk winds in compact objects in X-ray binaries, suggested by the blue-shifted absorption lines in spectroscopic data, are important phenomena to address the understanding of the physics of AGN feedback. Those objects show strong X-ray radiation from the accretion flows and clear absorption/emission lines of winds without contamination from stellar components and dust extinction of interstellar medium. However, the driving mechanisms of the winds are unclear. To tackle this, we build a comprehensive model for X-ray spectra. The detail line profiles are simulated by Monte-Carlo radiation transfer, whose input density/velocity fields are calculated by the radiation hydrodynamics code. Our models show that the observed spectra are well described by the winds launched at a larger radius driven by radiative heating/acceleration, where the mass/momentum/energy transfer to outer systems is calculable by the observed SED, luminosity, and the disk size. This motivates us to make quantitative models of AGN feedback for galaxy formation by radiative (accelerated/heated) winds determined by fundamental parameters related to black holes, such as mass and accretion rate.

Dr. Akihiro Inoue (Osaka University)

General relativistic radiation MHD simulations of super-Eddington accretion flows onto the magnetized neutron star

F608

Ultraluminous X-ray sources (ULXs) are bright, point-like, off-nuclear X-ray sources. Their X-ray luminosity exceeds the Eddington luminosity for the stellar mass black hole, and the energy production mechanism remains a great mystery. We have performed general relativistic radiation magnetohydrodynamics simulations of super-Eddington accretion flows onto neutron stars with dipole and quadrupole magnetic fields, as modeling the neutron-star-powered ULXs. In our simulations, accretion disk, accretion flows along the neutron star’s magnetic field, and optically thick outflows driven by the strong radiation force appear. Such outflows can explain the thermal emission with a temperature of 1E+7 K and a blackbody radius of ~100 km detected in ULX. In this talk, the magnetic field structure (strength and configuration) of the neutron star in the ULXs is also discussed.