|4 月 10 日||野上||
Title: Superflares on solar-type stars
Superflares are eruptive phenomena, like flares on the Sun, but the total energy radiated during one superflare is 10-10^4 times larger than that of the most energetic flare on the Sun observed so far. Such superflares have been known to occure in some young stars, RS CVn-type binaries, and dMe stars. Maehara et al. (2012, Nature, 485, 478) found 365 flares on 145 G-type main sequence stars (solar-type stars) in the Kepler archive data publicly available. I will make a short introduction on the superflare for newcomers to Wednesday seminar, review our recent works after this discovery paper, and discus some future plans.
|4 月 17 日||市川||
Title: AGN torus models
I will briefly introduce the AGN unified model and the history of two torus models (smooth and clumpy). I will also review the recent results by authors who applied clumpy torus models into the observations (Mor et al. 09, 11, 12).
|4 月 24 日||休会||
|5 月 1 日||小倉||
Title: Observational Appearance and Spectrum of Black Hole Winds: Effect of Electron Scattering
In this talk I will present our study on the black hole wind.
In the relativistic outflows, we should carefully consider the apparent photosphere (Abramowicz et al. 1991). Because it is not spherical, but becomes a non-spherical shape since the flow density gradually changes. In addition, in a high temperature outflow, electron scattering plays an important role. Taking this scattering effect into considerations, we examine the black hole wind. Unexpectedly, we find that the shape of the thermalization surface is nearly spherical and the spectrum is almost blackbody, although the apparent photosphere is highly aspherical.
|5 月 8 日||長尾||
Title: Recent submillimetric [CII] observations of high-z quasars
I would review some papers describing submillimetric [CII] observations for high-z quasars.
References (looks too many, but actually most of them are letters):
Maiolino, Cox, et al. (incl. Nagao) A&A, 440, L51 (2005)
Maiolino, Caselli, Nagao, et al. A&A, 500, L1 (2009)
Walter, Riechers, Cox, et al. Nature, 457, 699 (2009)
Maiolino, Gallerani, Neri, et al. MNRAS, 425, L66 (2012)
Venemans, McMahon, Walter, et al. ApJ, 751, L25 (2012)
Wang, Wagg, Carilli, et al. ApJ, subm. (arXiv:1302.4154)
|5 月 15 日||笹田||
I will talk about the Kepler observations of AGNs. My presentation is based on these paper;
Edelson et al 2013 http://adsabs.harvard.edu/abs/2013ApJ...766...16E
Mushotzky et al. 2011 http://adsabs.harvard.edu/abs/2011ApJ...743L..12M
|5 月 22 日||休会||
COSMOS Meeting in Kyoto開催のため
|5 月 29 日||山中||
|6 月 5 日||田崎||
In the next seminar, I will talk about "AGN feedback", based on Fabian (2012), ARA&A, 50, 455 (http://ads.nao.ac.jp/abs/2012ARA%26A..50..455F). And my study on radio-loud AGNs will be related to the AGN feedback in my talk.
|6 月 12 日||上田||
Tomorrow I will talk on the evolution of black hole mass function and Eddington ratio distribution of AGN based on recent results from the SXDS and SDSS.
http://ads.nao.ac.jp/abs/2012ApJ...761..143N http://ads.nao.ac.jp/abs/2012ApJ...746..169S http://ads.nao.ac.jp/abs/2013ApJ...764...45K
|6 月 19 日||Ricci||
My talk tomorrow will be about reflection from ionised and neutral matter in Active Galactic Nuclei. I will introduce you to some of the main issues of X-ray extragalactic astrophysics (how is the soft excess produced? Do the broad iron line and the hard excess come from reflection or absorption?) and to their possible explanations.
The main references are the review of Turner and Miller (2009)
and the recent work of Risaliti et al. (2013) using the first NuStar results http://adsabs.harvard.edu/abs/2013Natur.494..449R
|6 月 26 日||池田||
In the next seminar, I would like to talk about the z=5 quasar luminosity function from COSMOS and SDSS Stripe 82.
Ikeda et al. (2012), ApJ, 756, 160 http://adsabs.harvard.edu/abs/2012ApJ...756..160I
McGreer et al. (2013), ApJ, 768, 105 http://adsabs.harvard.edu/abs/2013ApJ...768..105M
|7 月 3 日||大島||
Osaki, Yoji; Kato, Taichi ”Study of Superoutbursts and Superhumps in SU UMa Stars by the Kepler Light Curves of V344 Lyrae and V1504 Cygni" (arXiv:1305.5877)
Osaki, Yoji; Kato, Taichi ”The Cause of the Superoutburst in SU UMa Stars is Finally Revealed by Kepler Light Curve of V1504 Cygni" (arXiv:1212.1516)
|7 月 10 日||志達||
In the next seminar, I will review previous studies on the disk winds in black hole X-ray binaries and introduce you to the recent results of the newly discovered black hole candidate MAXI J1305-704 (Shidatsu et al. 2013 and Miller et al. 2013, both submitted to ApJ).
|7 月 17 日||休会||
|7 月 24 日||山中||