Zobrazeno 1 - 10
of 140
pro vyhledávání: '"Fumio Takahara"'
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 457:1124-1136
We examine the plasma composition of relativistic jets in four FRII radio galaxies by analyzing the total cocoon pressure in terms of partial pressures of thermal and non-thermal electrons/positrons and protons. The total cocoon pressure is determine
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::63266c913124824e8126109217573d31
https://doi.org/10.1093/mnras/stw010
https://doi.org/10.1093/mnras/stw010
Autor:
Fumio Takahara, Masaaki Kusunose
X-ray bright knots of kpc-scale jets of several radio loud quasars have been an actively discussed issue. Among various models to explain observations, synchrotron radiation from the electron population different from radio to IR emitting electrons i
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9bb286b45a6d07e5b967d2a608618436
http://arxiv.org/abs/1805.10764
http://arxiv.org/abs/1805.10764
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 449:551-558
We examine the applicability of the stochastic electron acceleration to two high synchrotron peaked blazars, Mrk 421 and Mrk 501, assuming synchrotron self-Compton emission of gamma-rays. Our model considers an emitting region moving at relativistic
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b8980b92dc7970c5ec3626b6e71e5a1d
https://doi.org/10.1093/mnras/stv281
https://doi.org/10.1093/mnras/stv281
Autor:
Fumio Takahara, Masaaki Kusunose
Strong X-ray emission from large scale jets of radio loud quasars still remains an open problem. Models based on inverse Compton scattering off CMB photons by relativistically beamed jets have recently been ruled out, since Fermi LAT observations for
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f1a259da3e723bfc112a36b15248754c
http://arxiv.org/abs/1611.08046
http://arxiv.org/abs/1611.08046
In supernova remnants, the nonlinear amplification of magnetic fields upstream of collisionless shocks is essential for the acceleration of cosmic rays to the energy of the "knee" at 1015.5 eV. A nonresonant instability driven by the cosmic ray curre
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::252569ad9145689c907b147037e36013
https://doi.org/10.1088/0004-637x/698/1/445
https://doi.org/10.1088/0004-637x/698/1/445
Autor:
Fumio Takahara, Kenji Toma
The Blandford-Znajek process, the steady electromagnetic energy extraction from a rotating black hole, is widely believed to work for driving relativistic jets, although it is still under debate where the electric current is driven. We address this i
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ef3c2e21c8b1e1cc4ecb1aefc577faaa
Publikováno v:
Monthly Notices of the Royal Astronomical Society. 415:3434-3438
We study the escape of cosmic ray (CR) protons accelerated in a supernova remnant (SNR) by numerically solving a diffusion–convection equation for regions from the vicinity of the shock front to those far away from the front. We consider the amplif
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::1d64e7be06eca7b7825c17b09d8cdd37
https://doi.org/10.1111/j.1365-2966.2011.18980.x
https://doi.org/10.1111/j.1365-2966.2011.18980.x
Autor:
Fumio Takahara, Masaki Yamaguchi
Publikováno v:
The Astrophysical Journal. 717:85-92
The emission mechanism of the gamma-ray binary LS5039 in energy bands of TeV, GeV, and X-ray is investigated. Observed light curves in LS5039 show that TeV and GeV fluxes anticorrelate and TeV and X-ray fluxes correlate. However, such correlated vari
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ac1f8279faf8b64ff69ab199c17b543c
https://doi.org/10.1088/0004-637x/717/1/85
https://doi.org/10.1088/0004-637x/717/1/85
Publikováno v:
Publications of the Astronomical Society of Japan. 61:1229-1235
The 3rd Suzaku international Conference "Energetic Cosmos : from Suzaku to ASTRO-H" (June 29-July 2, 2009. Grand Park Otaru Hotel), Otaru, Hokkaido Japan
We present the analysis of Suzaku observations of the young open cluster Westerlund 2, whic
We present the analysis of Suzaku observations of the young open cluster Westerlund 2, whic
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::2546705cd7809728e8b4f98a593aa1e8
https://doi.org/10.1093/pasj/61.6.1229
https://doi.org/10.1093/pasj/61.6.1229
Autor:
Katsuaki Asano, Fumio Takahara
Publikováno v:
The Astrophysical Journal. 690:L81-L84
Through detailed numerical simulations, we demonstrate that relativistic outflows (Lorentz factor $\Gamma \sim 7$) of electron-positron pairs can be produced by radiative acceleration even when the flow starts from a nearly pair equilibrium state at
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::89517aa7276126214c5e308ce5d3b560
https://doi.org/10.1088/0004-637x/690/1/l81
https://doi.org/10.1088/0004-637x/690/1/l81