Host Galaxies of Young Dust-Reddened Quasars

نویسندگان

  • Weimin Wang
  • Zhaoqing Yang
  • Zhijian Luo
  • T. Urrutia
  • M. Lacy
چکیده

We present results on a multiwavelength campaign to identify the nature of dust-reddened Type 1 quasars. These quasars were selected by matching FIRST, 2MASS and very red optical counterparts with r − K > 5. We find a very high fraction of Low Ionization Broad Absorption Line Quasars (LoBALs) among AGN selected with this method, perhaps a sign of quasar feedback. From X-ray observations and Balmer decrement measurements, the obscuring dust is most likely located in a cold absorber such as the host galaxy, rather than from a torus near the AGN. Hubble ACS imaging of a sub-sample of these sources showed a very high fraction of interacting and merging systems. The quasars appear to be very young in which dust from the merging galaxies is still settling in. Spitzer IRS and MIPS data show star formation signatures and deep Silicate absorption features in these objects, but overall the quasar is the dominant source in the Mid-infrared.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Evidence for Quasar Activity Triggered by Galaxy Mergers in Hst Observations of Dust-reddened Quasars

We present Hubble Space Telescope ACS images of 13 dust-reddened type 1 quasars selected from the FIRST/ 2MASS Red Quasar Survey. These quasars have high intrinsic luminosities after correction for dust obscuration ( 23:5 MB 26:2 from K-magnitude). The images show strong evidence of recent or ongoing interaction in 11 of the 13 cases, even before the quasar nucleus is subtracted. None of the ho...

متن کامل

The First-2mass Red Quasar Survey Ii: an Anomalously High Fraction of Lobals in Searches for Dust-reddened Quasars

We present results on a survey to find extremely dust-reddened Type-1 Quasars. Combining the FIRST radio survey, the 2MASS Infrared Survey and the Sloan Digital Sky Survey, we have selected a candidate list of 122 potential red quasars. With more than 80% spectroscopically identified objects, well over 50% are classified as dust-reddened Type 1 quasars, whose reddenings (E(B-V)) range from appr...

متن کامل

The Reddest Quasars

In a survey of quasar candidates selected by matching the FIRST and 2MASS catalogs, we have found two extraordinarily red quasars. FIRST J013435.7−093102 is a 1 Jy source at z = 2.216 and has B −K & 10, while FIRST J073820.1+275045 is a 2.5 mJy source at z=1.985 with B −K ≈ 8.4. FIRST J073820.1+275045 has strong absorption lines of Mg II and C IV in the rest frame of the quasar and is highly po...

متن کامل

No Evidence of ‘gray’ Dust from Composite Quasar Spectra

Two recent studies based on composite reddened quasar spectra have indicated the presence of ‘gray’ dust in quasar environments. This gray dust has a relatively flat extinction law in the UV, consistent with the theoretical expectation of a lack of small dust grains close to a quasar. In contrast, individual reddened quasars in the Sloan Digital Sky Survey tend to have steep extinction laws in ...

متن کامل

No Evidence for ‘grey’ Dust from Composite Quasar Spectra

Two recent studies based on composite reddened quasar spectra have indicated the presence of ‘grey’ dust in quasar environments. This grey dust has a relatively flat extinction law in the UV, consistent with the theoretical expectation of a lack of small dust grains close to a quasar. In contrast, individual reddened quasars in the SDSS tend to have steep extinction laws in the UV, similar to t...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2009