Search Publications
Multiwavelength Observations of the Powerful Gamma-Ray Quasar PKS 1510-089: Clues on the Jet Composition
Kataoka, J.; Kawai, N.; Tosti, G. +16 more
We present the results from a multiwavelength campaign conducted in 2006 August of the powerful γ-ray quasar PKS 1510-089 (z = 0.361). This campaign commenced with a deep Suzaku observation lasting 3 days for a total exposure time of 120 ks and continued with Swift monitoring over 18 days. Besides Swift observations, the campaign included ground-b…
The Physical Scale of the Far-Infrared Emission in the Most Luminous Submillimeter Galaxies
Wilner, David J.; Yun, Min S.; Fazio, Giovanni G. +10 more
We present high-resolution submillimeter interferometric imaging of two of the brightest high-redshift submillimeter galaxies known: GN 20 and AzTEC1 at 0.8'' and 0.3'' resolution, respectively. Our data—the highest resolution submillimeter imaging of high-redshift sources accomplished to date—were collected in three different array configurations…
Discovery of a Very Bright Strongly Lensed Galaxy Candidate at z ≈ 7.6
Ford, H. C.; Frye, B. L.; Infante, L. +11 more
Using Hubble Space Telescope (HST) and Spitzer IRAC imaging, we report the discovery of a very bright strongly lensed Lyman break galaxy (LBG) candidate at z ~ 7.6 in the field of the massive galaxy cluster Abell 1689 (z = 0.18). The galaxy candidate, which we refer to as A1689-zD1, shows a strong z850 - J110 break of at leas…
A Massive Neutron Star in the Globular Cluster M5
Freire, Paulo C. C.; Hessels, Jason W. T.; van den Berg, Maureen +1 more
We report the results of 19 years of Arecibo timing for two pulsars in the globular cluster NGC 5904 (M5), PSR B1516+02A (M5A) and PSR B1516+02B (M5B). This has resulted in the measurement of the proper motions of these pulsars and, by extension, that of the cluster itself. M5B is a 7.95 ms pulsar in a binary system with a >0.13 M⊙ c…
Precise Measurement of the Spin Parameter of the Stellar-Mass Black Hole M33 X-7
McClintock, Jeffrey E.; Liu, Jifeng; Davis, Shane W. +2 more
In prior work, Chandra and Gemini-North observations of the eclipsing X-ray binary M33 X-7 have yielded measurements of the mass of its black hole primary and the system's orbital inclination angle of unprecedented accuracy. Likewise, the distance to the binary is known to a few percent. In an analysis based on these precise results, 15 Chandra an…
Hubble Space Telescope Morphologies of Local Lyman Break Galaxy Analogs. I. Evidence for Starbursts Triggered by Merging
Charlot, Stéphane; Aloisi, Alessandra; Heckman, Timothy M. +10 more
Heckman and coworkers used the GALEX UV imaging survey to show that there exists a rare population of nearby compact UV-luminous galaxies (UVLGs) that closely resemble high-redshift Lyman break galaxies (LBGs). We present HST images in the UV, optical, and Hα and resimulate them at the depth and resolution of the GOODS/UDF fields to show that the …
Are Optically Selected Quasars Universally X-Ray Luminous? X-Ray-UV Relations in Sloan Digital Sky Survey Quasars
Brandt, W. N.; Schneider, Donald P.; Gibson, Robert R.
We analyze archived Chandra and XMM-Newton X-ray observations of 536 Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) quasars (QSOs) at 1.7 <= z<= 2.7 in order to characterize the relative UV and X-ray spectral properties of QSOs that do not have broad UV absorption lines (BALs). We constrain the fraction of X-ray-weak, non-BAL QSOs and …
Reaching the End of the White Dwarf Cooling Sequence in NGC 6791
Anderson, Jay; Salaris, Maurizio; Bedin, Luigi R. +4 more
We present new observations of the white dwarf sequence of the old open cluster NGC 6791. The brighter peak previously observed in the white dwarf luminosity function (WDLF) is now better delineated, and the second, fainter peak that we suggested earlier is now confirmed. A careful study suggests that we have reached the end of the WD sequence. Th…
AMUSE-Virgo. I. Supermassive Black Holes in Low-Mass Spheroids
Treu, Tommaso; Marshall, Philip J.; Antonucci, Robert +3 more
We present the first results from the AGN Multiwavelength Survey of Early-Type Galaxies in the Virgo Cluster (AMUSE-Virgo). This large program targets 100 early-type galaxies with the Advanced CCD Imaging Spectrometer on board the Chandra X-Ray Observatory and the Multiband Imaging Photometer on board the Spitzer Space Telescope, with the aim of p…
INTEGRAL SPI All-Sky View in Soft Gamma Rays: A Study of Point-Source and Galactic Diffuse Emission
Bouchet, L.; Terrier, R.; Diehl, R. +4 more
We have processed the data accumulated with the INTEGRAL SPI instrument over 4 years (~51 Ms) to study the morphology of the Galactic "diffuse" emission in the 20 keV to 8 MeV energy range. To achieve this, we simultaneously derived an all-sky census of emitting sources and images of the Galactic ridge (GR) emission. In the central radian, the res…