相关论文: CC Bootis: QSO, Not Variable Halo Giant

Red quasi-stellar objects (QSOs) are a subset of the luminous end of the cosmic population of active galactic nuclei (AGN), most of which are reddened by intervening dust along the line-of-sight towards their central engines. In recent work…

We present a new suite of photometric and spectroscopic data for the faint Bootes II dwarf spheroidal galaxy candidate. Our deep photometry, obtained with the INT/WFC, suggests a distance of 46 kpc and a small half-light radius of 4.0…

The Cygnus Superbubble (CSB) is a region of soft X-ray emission approximately 13 degrees wide in the direction of the local spiral arm. Such a large region might be the result of strong stellar winds and supernovae from nearby stellar…

Motivated by the existence of binary systems where a stellar-mass black hole is bound to a normal star, we selected four red giants with large radial velocity (RV) variation from the survey of SIM grid stars and monitored their RVs for…

We have discovered two new high redshift (z=2.38) galaxies, near the previously known z=2.38 galaxy 2139-4434 B1 (Francis et al. 1996). All three galaxies are strong Ly-alpha emitters, and have much redder continuum colors (I-K about 5)…

We present a multi-wavelength study of three new $z\sim5.6$ quasi-stellar objects (QSOs) identified from dedicated spectroscopic observations. The three sources were selected as high-$z$ candidates based on their radio and…

We have obtained high resolution spectropolarimetric data for the planet-hosting star $\tau$ Bootis, using the ESPaDOnS spectropolarimeter at CFHT. A weak but clear Stokes $V$ signature is detected on three of the four nights of June 2006…

The discovery of an HI cloud with peculiar properties at equatorial coordinates (J2000) ra=07h49m, dec=04d30m is presented. The HI object was detected at 21cm using the 300-m NAIC Arecibo telescope. Subsequent follow-up high-resolution…

X-ray observations have unveiled the existence of enigmatic point-like sources at the center of young (a few kyrs) supernova remnants. These sources, known as Central Compact Objects (CCOs), are thought to be neutron stars produced by the…

In this paper, the availability of multi-wavelength optical/infrared information of FIRST (Faint Images of the Radio Sky at 20 cm) radio sources counterparts over ~9.2 deg^{2} in Bootes field and ~2.4 deg^{2} in Cetus field is exploited to…

Abridged) In the SDSS, several unusual QSOs have been discovered that have very blue rest-frame UV spectra but no discernible emission lines. Their UV spectra strongly resemble that of the newly discovered quasar PHL 1811 ($z=0.192$; $\rm…

We discuss broad- and narrow-band imaging of 7 arcmin fields of 14 QSOs with redshift ~1.1. The narrow-band filters were chosen to detect redshifted [O II] 3727A, and the broad bands are R and I, which correspond to rest wavelengths…

The detection of rapid variability on a time-scale of hours in radio-quiet quasars (RQQSOs) could be a powerful discriminator between starburst, accretion disc and relativistic jet models of these sources. This paper contains an account of…

We report on a wide-area (48' x 9') imaging survey of faint galaxies in R and I bands toward the 1338+27 field where an unusual concentration of five QSOs at z\sim1.1, embedded in a larger-scale clustering of 23 QSOs, is known to exist.…

The 355 optically polarized QSOs have redshifts from 0.061 to 3.94 and are spread out over the sky except for a 60 degree band centered on the Galactic Equator. The data we analyze was measured, collected and published by others. Here, we…

We present the first unambiguous case of external variability of a radio gravitational lens, CLASS B1600+434. The VLA 8.5-GHz difference light curve of the lensed images, taking the proper time-delay into account, shows the presence of…

We use sensitive observations of three high redshift sources; [CII] fine structure and CO(2-1) rotational transitions for the z=6.4 Quasar host galaxy (QSO) J1148+5251, and [CII] and CO(5-4) transitions from the QSO BR1202-0725 and its…

{}From three quasar samples with a total of 1038 objects in the redshift range $1.0 \div 2.2$ we measure the variance $\sigma^2$ of counts in cells of volume $V_u$. By a maximum likelihood analysis applied separately on these samples we…

The proto-galaxy, cB58, was discovered in the CNOC survey of cluster redshifts. Absorption features reveal that this system is at a redshift of $z=2.72$, implying an absolute magnitude of ${\rm M_v \sim -26}$, and a star-formation rate of…

The redshift range from 2.2 to 3, is known as the 'redshift desert' of quasars because quasars with redshift in this range have similar optical colors as normal stars and are thus difficult to be found in optical sky surveys. A quasar…