Search Publications
The Baryon Oscillation Spectroscopic Survey of SDSS-III
Weiner, Benjamin J.; Finley, Hayley; Brandt, W. N. +162 more
The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large-scale structure. BOSS uses 1.5 million luminous galaxies as faint as i = 19.9 over 10,000 deg2…
The Second Fermi Large Area Telescope Catalog of Gamma-Ray Pulsars
Troja, E.; Caraveo, P. A.; Orlando, E. +208 more
This catalog summarizes 117 high-confidence >=0.1 GeV gamma-ray pulsar detections using three years of data acquired by the Large Area Telescope (LAT) on the Fermi satellite. Half are neutron stars discovered using LAT data through periodicity searches in gamma-ray and radio data around LAT unassociated source positions. The 117 pulsars are eve…
Unifying the observational diversity of isolated neutron stars via magneto-thermal evolution models
Rea, N.; Perna, R.; Pons, J. A. +3 more
Observations of magnetars and some of the high magnetic field pulsars have shown that their thermal luminosity is systematically higher than that of classical radio-pulsars, thus confirming the idea that magnetic fields are involved in their X-ray emission. Here we present the results of 2D simulations of the fully coupled evolution of temperature…
Swings between rotation and accretion power in a binary millisecond pulsar
Wieringa, M. H.; Campana, S.; Stella, L. +20 more
It is thought that neutron stars in low-mass binary systems can accrete matter and angular momentum from the companion star and be spun-up to millisecond rotational periods. During the accretion stage, the system is called a low-mass X-ray binary, and bright X-ray emission is observed. When the rate of mass transfer decreases in the later evolutio…
Irradiation of an accretion disc by a jet: general properties and implications for spin measurements of black holes
Reynolds, C. S.; Dauser, T.; Wilms, J. +5 more
X-ray irradiation of the accretion disc leads to strong reflection features, which are then broadened and distorted by relativistic effects. We present a detailed, general relativistic approach to model this irradiation for different geometries of the primary X-ray source. These geometries include the standard point source on the rotational axis a…
Planck intermediate results. V. Pressure profiles of galaxy clusters from the Sunyaev-Zeldovich effect
Böhringer, H.; Kneissl, R.; Dahle, H. +215 more
Taking advantage of the all-sky coverage and broadfrequency range of the Planck satellite, we study the Sunyaev-Zeldovich (SZ) and pressure profiles of 62 nearby massive clusters detected at high significance in the 14-month nominal survey. Careful reconstruction of the SZ signal indicates that most clusters are individually detected at least out …
Galaxy Cluster Baryon Fractions Revisited
Zabludoff, Ann I.; Gonzalez, Anthony H.; Zaritsky, Dennis +1 more
We measure the baryons contained in both the stellar and hot-gas components for 12 galaxy clusters and groups at z ~ 0.1 with M = 1-5 × 1014 M ⊙. This paper improves upon our previous work through the addition of XMM-Newton X-ray data, enabling measurements of the total mass and masses of each major baryonic component—intracl…
Suzaku observations of `bare' active galactic nuclei
Fabian, A. C.; Nardini, E.; Reis, R. C. +2 more
We present an X-ray spectral analysis of a large sample of 25 `bare' active galactic nuclei (AGN), sources with little or no complicating intrinsic absorption, observed with Suzaku. Our work focuses on studying the potential contribution from relativistic disc reflection and examining the implications of this interpretation for the intrinsic spect…
Measurement of the Radius of Neutron Stars with High Signal-to-noise Quiescent Low-mass X-Ray Binaries in Globular Clusters
Guillot, Sebastien; Webb, Natalie A.; Servillat, Mathieu +1 more
This paper presents the measurement of the neutron star (NS) radius using the thermal spectra from quiescent low-mass X-ray binaries (qLMXBs) inside globular clusters (GCs). Recent observations of NSs have presented evidence that cold ultra dense matter—present in the core of NSs—is best described by "normal matter" equations of state (EoSs). Such…
A rapidly spinning supermassive black hole at the centre of NGC 1365
Harrison, F. A.; Zhang, W. W.; Nardini, E. +9 more
Broad X-ray emission lines from neutral and partially ionized iron observed in active galaxies have been interpreted as fluorescence produced by the reflection of hard X-rays off the inner edge of an accretion disk. In this model, line broadening and distortion result from rapid rotation and relativistic effects near the black hole, the line shape…