Search Publications
The Nature of Growing Bulges Within z < 1.3 Galaxy Disks in the GOODS-N Field
Balcells, Marc; Domínguez-Palmero, Lilian
We analyze central surface brightness µ0, nuclear and global colors of intermediate redshift disk galaxies. On an apparent-diameter-limited sample of 398 galaxies from ACS/HST (Advanced Camera for Surveys in the Hubble Space Telescope) The Great Observatories Origins Deep Survey North (GOODS-N), we find 131 galaxies with bulges an…
AKARI Near- and Mid-Infrared Spectroscopy of APM 08279+5255 at z = 3.91
Kawara, K.; Ohyama, Y.; Oyabu, S. +4 more
We present rest-frame optical/near-infrared spectra of the gravitationally lensed quasar APM 08279+5255 at z = 3.91 that has been taken using the Infrared Camera (IRC) onboard the AKARI infrared satellite. The observed continuum consists of two components; a power-law component dominating optical wavelengths which is the direct light from the cent…
HR 8257: A Three-Dimensional Orbit and Basic Properties
Torres, Guillermo; Fekel, Francis C.; Boden, Andrew F. +1 more
We have used interferometric and spectroscopic observations of HR 8257 to determine a three-dimensional orbit of the system. The orbit has a period of 12.21345 days and an eccentricity of 0.2895. The masses of the F0 and F2 dwarf components are 1.56 and 1.38 M sun, respectively, with fractional errors of 1.4%. Our orbital parallax of 13…
Metal-Enriched Outflows in the Ultraluminous Infrared Quasar Q1321+058
Yuan, Weimin; Zhou, Hongyan; Wang, Tinggui +3 more
Quasar outflows may play important role in the evolution of its host galaxy and central black hole, and are most often studied in absorption lines. In this paper, we present a detailed study of multiple outflows in the obscured ultraluminous infrared quasar Q1321+058. The outflows reveal themselves in the complex optical and ultraviolet (UV) emiss…
Enhanced Lensing Rate by Clustering of Massive Galaxies: Newly Discovered Systems in the Slacs Fields
Treu, Tommaso; Marshall, Philip J.; Newton, Elisabeth R.
Galaxy-scale strong gravitational lens systems are useful for a variety of astrophysical applications. However, their use is limited by the relatively small samples of lenses known to date. It is thus important to develop efficient ways to discover new systems both in present and forthcoming data sets. For future large high-resolution imaging surv…
Evolution of the Lyα Halos Around High-Redshift Radio Galaxies
Dickinson, Mark; Dey, Arjun; Zirm, Andrew W. +1 more
We have obtained the first constraints on extended Lyα emission at z ~ 1 in a sample of five radio galaxies. We detect Lyα emission from four of the five galaxies. The Lyα luminosities range from 0.1-4 × 1043 erg s-1 and are much smaller than those observed for halos around higher redshift radio galaxies. If the z ≈ 1 radio g…
The Fermi/LAT Sky as Seen by INTEGRAL/IBIS
Bird, A. J.; Ubertini, P.; Bassani, L. +3 more
In this Letter we present the result of the cross correlation between the fourth INTEGRAL/IBIS soft gamma-ray catalog, in the range 20-100 keV, and the Fermi LAT bright source list of objects emitting in the 100 MeV-100 GeV range. The main result is that only a minuscule part of the more than 720 sources detected by INTEGRAL and the population of …
Chandra Discovery of an Intermediate Polar in Baade's Window
Laycock, Silas; van den Berg, Maureen; Grindlay, Jonathan E. +2 more
We have discovered an intermediate polar (IP) in the 100 ks Chandra observation of Baade's window (BW), a low extinction region at about 4° south of the Galactic center. The source exhibits large X-ray modulations at a period of 1028.4 s in the 0.3-8 keV band. The X-ray spectral fit with a power-law model shows that the integrated spectrum is intr…
A Pilot Search for Population III Supernova Candidates in the Spitzer/IRAC Dark Field
Krick, Jessica; Surace, Jason; Moustakas, Leonidas A. +1 more
We have undertaken a systematic search for candidate supernovae from high-redshift Population III stars in a field that has been observed with repeated imaging on a cadence of 2-3 weeks over a 2.2 year baseline, the Spitzer/IRAC Dark Field. The individual epochs reach a typical 5σ depth of 1 µJy in IRAC Channel 1 (3.6 µm). Requiring a …
Tidal Stripping of Globular Clusters in the Virgo Cluster
Coenda, Valeria; Muriel, Hernán; Donzelli, Carlos
With the aim of finding evidence of tidal stripping of globular clusters (GCs) we analyzed a sample of 13 elliptical galaxies taken from the ACS Virgo Cluster Survey (VCS). These galaxies belong to the main concentration of the Virgo Cluster (VC) and present absolute magnitudes -18.5 < Mz < -22.5. We used the public GC catalog of …