Search Publications
The Hubble Space Telescope Cluster Supernova Survey. II. The Type Ia Supernova Rate in High-redshift Galaxy Clusters
Gladders, M. D.; Panagia, N.; Huang, X. +41 more
We report a measurement of the Type Ia supernova (SN Ia) rate in galaxy clusters at 0.9 < z < 1.46 from the Hubble Space Telescope Cluster Supernova Survey. This is the first cluster SN Ia rate measurement with detected z > 0.9 SNe. Finding 8 ± 1 cluster SNe Ia, we determine an SN Ia rate of 0.50+0.23 -0.19 (stat)
Resolving the Galaxies within a Giant Lyα Nebula: Witnessing the Formation of a Galaxy Group?
Dey, Arjun; Jannuzi, Buell T.; Soifer, B. T. +8 more
Detailed analysis of the substructure of Lyα nebulae can put important constraints on the physical mechanisms at work and the properties of galaxies forming within them. Using high-resolution Hubble Space Telescope (HST) imaging of a Lyα nebula at z ≈ 2.656, we have taken a census of the compact galaxies in the vicinity, used optical/near-infrared…
Morphological Evolution of a Three-dimensional Coronal Mass Ejection Cloud Reconstructed from Three Viewpoints
Feng, L.; Inhester, B.; Wei, Y. +3 more
The propagation properties of coronal mass ejections (CMEs) are crucial to predict its geomagnetic effect. A newly developed three-dimensional (3D) mask fitting reconstruction method using coronagraph images from three viewpoints has been described and applied to the CME ejected on 2010 August 7. The CME's 3D localization, real shape, and morpholo…
A Deep, Wide-field, and Panchromatic View of 47 Tuc and the SMC with HST: Observations and Data Analysis Methods
Anderson, Jay; Dotter, Aaron; Rich, R. M. +10 more
In Hubble Space Telescope (HST) Cycle 17, we imaged the well-known globular star cluster 47 Tucanae for 121 orbits using the Wide Field Channel of the Advanced Camera for Surveys (ACS) and both the UV/visible (UVIS) and IR channels of the newly installed Wide Field Camera 3 (WFC3) instrument (GO-11677, PI: H. Richer). This unique data set was obta…
Major episodes of geologic history of Isidis Planitia on Mars
Hiesinger, H.; Ivanov, M. A.; Erkeling, G. +2 more
We have mapped the area of Isidis Planitia (1-27°N, 75-103°E) in order to assess the geologic history of this region using modern data sets such as MOLA topography and the high-resolution images provided by the HRSC, CTX, and HiRISE cameras. Results of our mapping show that the geologic history of Isidis Planitia consists of three principal episod…
Estimating the capture and loss of cold plasma from ionospheric outflow
Nilsson, H.; André, M.; Eriksson, A. +9 more
An important source of magnetospheric plasma is cold plasma from the terrestrial ionosphere. Low energy ions travel along the magnetic field lines and enter the magnetospheric lobes where they are convected toward the tail plasma sheet. Recent observations indicate that the field aligned ion outflow velocity is sometimes much higher than the conve…
XMM-Newton observations of GX 13 + 1: correlation between photoionised absorption and broad line emission
Díaz Trigo, M.; Parmar, A. N.; Boirin, L. +1 more
We analysed data from five XMM-Newton observations of GX 13 + 1 to investigate the variability of the photo-ionised absorber in this source. We fitted EPIC and RGS spectra obtained from the "least-variable" intervals with a model consisting of disc-blackbody and blackbody components together with a Gaussian emission feature at ~6.55-6.7 keV modifi…
Investigating the spectroscopic, magnetic and circumstellar variability of the O9 subgiant star HD 57682
Kaper, L.; Rivinius, Th.; Ribeiro, J. +12 more
The O9IV star HD 57682, discovered to be magnetic within the context of the Magnetism in Massive Stars (MiMeS) survey in 2009, is one of only eight convincingly detected magnetic O-type stars. Among this select group, it stands out due to its sharp-lined photospheric spectrum. Since its discovery, the MiMeS Collaboration has continued to obtain sp…
On the Role of the Accretion Disk in Black Hole Disk-Jet Connections
Fabian, A. C.; Miller, J. M.; Nowak, M. A. +5 more
Models of jet production in black hole systems suggest that the properties of the accretion disk—such as its mass accretion rate, inner radius, and emergent magnetic field—should drive and modulate the production of relativistic jets. Stellar-mass black holes in the "low/hard" state are an excellent laboratory in which to study disk-jet connection…
Galaxy cluster outskirts: a universal entropy profile for relaxed clusters?
Fabian, A. C.; Sanders, J. S.; Walker, S. A. +1 more
We fit a functional form for a universal intracluster medium entropy profile to the scaled entropy profiles of a catalogue of X-ray galaxy cluster outskirts results, which are all relaxed cool core clusters at redshift below 0.25. We also investigate the functional form suggested by Lapi et al. and Cavaliere et al. for the behaviour of the entropy…