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Constraints on Type Ia supernova progenitor time delays from high-z supernovae and the star formation history
Wolf, C.; Förster, F.; Podsiadlowski, Ph. +1 more
We re-assess the question of a systematic time delay between the formation of the progenitor and its explosion in a Type Ia supernova (SN Ia) using the Hubble Higher-z Supernova Search sample. While a previous analysis indicated a significant time delay, with a most likely value of 3.4 Gyr, effectively ruling out all previously proposed progenitor…
The AGN Outflow in the HDF-S Target QSO J2233-606 from a High-Resolution VLT UVES Spectrum
Arav, Nahum; Kim, Tae-Sun; Gabel, Jack R.
We present a detailed analysis of the intrinsic UV absorption in the central HDF-S target QSO J2233-606, based on a high-resolution, high-S/N (~25-50) spectrum obtained with VLT UVES. This spectrum samples the cluster of intrinsic absorption systems outflowing from the AGN at radial velocities v~-5000 to -3800 km s-1 in the key far-UV d…
An Investigation into the Variability of Heating in a Solar Active Region
Winebarger, Amy R.; Warren, Harry P.; Ugarte-Urra, Ignacio
Previous studies have indicated that both steady and impulsive heating mechanisms play a role in active region heating. In this paper, we present a study of 20 hours of soft X-ray and EUV observations of solar active region NOAA AR 8731. We examine the evolution of six representative loop structures that brighten and fade first from X-ray images a…
The XMM Large-Scale Structure survey: a well-controlled X-ray cluster sample over the D1 CFHTLS area
Maccagni, D.; Chiappetti, L.; Altieri, B. +24 more
We present the XMM Large-Scale Structure Survey (XMM-LSS) cluster catalogue corresponding to the Canada-France-Hawaii Telescope Legacy Survey D1 area. The list contains 13 spectroscopically confirmed, X-ray selected galaxy clusters over 0.8deg2 to a redshift of unity and so constitutes the highest density sample of clusters to date. Clu…
Enrichment in the Centaurus cluster of galaxies
Fabian, A. C.; Sanders, J. S.
We perform a detailed spatially resolved, spectroscopic, analysis of the core of the Centaurus cluster of galaxies using a deep Chandra X-ray observation and XMM-Newton data. The Centaurus cluster core has particularly high metallicity, up to twice the solar values, and we measure the abundances of Fe, O, Ne, Mg, Si, S, Ar, Ca and Ni. We map the d…
The Evolution of the Mass Function Split by Morphology up to Redshift 1 in the FORS Deep and the GOODS-S Fields
Pannella, M.; Salvato, M.; Saglia, R. P. +5 more
We study the evolution of the stellar mass density for the separate families of bulge-dominated and disk-dominated galaxies over the redshift range 0.25<=z<=1.15. We derive quantitative morphology for a statistically significant galaxy sample of 1645 objects selected from the FORS Deep Field and the GOODS-S field. We find that the morphologi…
Do Ultraluminous X-Ray Sources Really Contain Intermediate-Mass Black Holes?
Ebisawa, Ken; Mineshige, Shin; Kawaguchi, Toshihiro +1 more
An open question remains whether Ultraluminous X-ray Sources (ULXs) really contain intermediate-mass black holes (IMBHs). We carefully investigated the XMM-Newton EPIC spectra of four ULXs that were claimed to be strong candidates of IMBHs by several authors. We first tried fitting by the standard spectral model of disk blackbody (DBB) + power-law…
Identifications of Four INTEGRAL Sources in the Galactic Plane via Chandra Localizations
Kaaret, Philip; Walter, Roland; Tomsick, John A. +3 more
Hard X-ray imaging of the Galactic plane by the INTEGRAL satellite is uncovering large numbers of 20-100 keV ``IGR'' sources. We present results from Chandra, INTEGRAL, optical, and IR observations of four IGR sources: three sources in the Norma region of the Galaxy (IGR J16195-4945, IGR J16207-5129, and IGR J16167-4957) and one that is closer to …
Constraint on the post-Newtonian parameter γ on galactic size scales
Bolton, Adam S.; Burles, Scott; Rappaport, Saul
We constrain the post-Newtonian gravity parameter γ on kiloparsec scales by comparing the masses of 15 elliptical lensing galaxies from the Sloan Lens ACS Survey as determined in two independent ways. The first method assumes only that Newtonian gravity is correct and is independent of γ, while the second uses gravitational lensing which depends o…
Dense, Fe-rich Ejecta in Supernova Remnants DEM L238 and DEM L249: A New Class of Type Ia Supernova?
Reynolds, Stephen P.; Borkowski, Kazimierz J.; Hendrick, Sean P.
We present observations of two LMC supernova remnants (SNRs), DEM L238 and DEM L249, with the Chandra and XMM-Newton X-ray satellites. Bright central emission, surrounded by a faint shell, is present in both remnants. The central emission has an entirely thermal spectrum dominated by strong Fe L-shell lines, with the deduced Fe abundance in excess…