Yukiyasu Kobayashi

Multiple Regression Analysis of the Variable Component in the Near-Infrared Region for Type 1 AGN MCG+08-11-011 (2006)

Tomita, Hiroyuki, Yoshii, Yuzuru, Kobayashi, Yukiyasu, Minezaki, Takeo, Enya, Keigo, Suganuma, Masahiro, ...

We propose a new method of analysing a variable component for type 1 active galactic nuclei (AGNs) in the near-infrared wavelength region. This analysis uses a multiple regression technique and...

The Optical/Near-Infrared Light Curves of SN 2002ap for the First 1.5 Years after Discovery (2006)

Tomita, Hiroyuki, Deng, Jinsong, Maeda, Keiichi, Yoshii, Yuzuru, Nomoto, Ken'ichi, Mazzali, Paolo A., ...

Late-time BVRIJHK photometry of the peculiar Type Ic SN 2002ap, taken between 2002 June 12 and 2003 August 29 with the MAGNUM telescope, is presented. The light curve decline rate is derived in each...

JHK' Imaging Photometry of Seyfert 1 AGNs and Quasars I: Multi-Aperture Photometry (2002)

Enya, Keigo, Yoshii, Yuzuru, Kobayashi, Yukiyasu, Minezaki, Takeo, Tomita, Hiroyuki, Peterson, Bruce A.

Near-infrared $JHK'$ imaging photometry was obtained of 331 AGNs consisting mainly of Seyfert 1 AGNs and quasars (QSOs). This sample was selected to cover a range of radio emission strength, redshift...

$JHK'$ Imaging Photometry of Seyfert 1 AGNs and Quasars II: Observation of Long-Term Variability (2002)

Enya, Keigo, Yoshii, Yuzuru, Kobayashi, Yukiyasu, Minezaki, Takeo, Tomita, Hiroyuki, Peterson, Bruce A.

Observations of 226 AGNs in the near-infrared $J$, $H$, and $K'$ bands are presented along with the analysis of the observations for variability. Our sample consists mainly of Seyfert 1 AGNs and...

$JHK'$ Imaging Photometry of Seyfert 1 AGNs and Quasars III: Variability of Radio Quiet and Radio Loud AGNs (2002)

Enya, Keigo, Yoshii, Yuzuru, Kobayashi, Yukiyasu, Minezaki, Takeo, Tomita, Hiroyuki, Peterson, Bruce A.

Variability of 226 AGNs in the near-infrared $J$, $H$, and $K'$ bands is analyzed and discussed. An ensemble average for measured variabilities was obtained for various samples of the AGNs divided by...

A Group of Galaxies at Redshift 2.38 (1995)

Francis, Paul, Woodgate, Bruce, Warren, Steve, Moller, Palle, Mazzolini, Marg, Bunker, Andy, ...

We report the discovery of a group of galaxies at redshift 2.38. We imaged about 10% of a claimed supercluster of QSO absorption-lines at z=2.38 (Francis & Hewett 1993). In this small field (2 arcmin...