Search Publications
Prospect of Studying Hard X- and Gamma-Rays from Type Ia Supernovae
Yamaguchi, H.; Diehl, R.; Tamagawa, T. +9 more
We perform multi-dimensional, time-dependent radiation transfer simulations for hard X-ray and γ-ray emissions, following radioactive decays of 56Ni and 56Co, for two-dimensional delayed-detonation models of Type Ia supernovae (SNe Ia). The synthetic spectra and light curves are compared with the sensitivities of current and …
2007 TY430: A Cold Classical Kuiper Belt Type Binary in the Plutino Population
Ragozzine, Darin; Sheppard, Scott S.; Trujillo, Chadwick
Kuiper Belt object 2007 TY430 is the first wide, equal-sized, binary known in the 3:2 mean motion resonance with Neptune. The two components have a maximum separation of about 1 arcsec and are on average less than 0.1 mag different in apparent magnitude with identical ultra-red colors (g - i = 1.49 ± 0.01 mag). Using nearly monthly observations of…
The structure of star clusters in the outer halo of M31
Chapman, S.; Davies, M. B.; Mackey, A. D. +11 more
We present a structural analysis of halo star clusters in M31 based on deep Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) imaging. The clusters in our sample span a range in galactocentric projected distance from 13 to 100 kpc and thus reside in rather remote environments. Ten of the clusters are classical globulars, whilst four a…
The Atacama Cosmology Telescope: High-resolution Sunyaev-Zel'dovich Array Observations of ACT SZE-selected Clusters from the Equatorial Strip
Hilton, Matt; Hasselfield, Matthew; Sifón, Cristóbal +41 more
We present follow-up observations with the Sunyaev-Zel'dovich Array (SZA) of optically confirmed galaxy clusters found in the equatorial survey region of the Atacama Cosmology Telescope (ACT): ACT-CL J0022-0036, ACT-CL J2051+0057, and ACT-CL J2337+0016. ACT-CL J0022-0036 is a newly discovered, massive (sime 1015 M ⊙), high-re…
A relativistic iron emission line from the neutron star low-mass X-ray binary GX 3+1
Santangelo, A.; Kaaret, P.; Egron, E. +7 more
We present the results of a spectroscopic study of the Fe Kα emission of the persistent neutron-star atoll low-mass X-ray binary and type I X-ray burster GX 3+1 with the EPIC-PN on board XMM-Newton. The source shows a flux modulation over several years and we observed it during its fainter phase, which corresponds to an X-ray luminosity of LX…
A Direct Measurement of the Total Gas Column Density in Orion KL
Comito, C.; Schilke, P.; Lis, D. C. +7 more
The large number of high-J lines of C18O available via the Herschel Space Observatory provide an unprecedented ability to model the total CO column density in hot cores. Using the emission from all the observed lines (up to J = 15-14), we sum the column densities in each individual level to obtain the total column after correcting for t…
Galaxy alignments in very X-ray luminous clusters at z > 0.5
Hung, Chao-Ling; Ebeling, Harald
We present the results of a search for galaxy alignments in 12 galaxy clusters at z > 0.5, a statistically complete subset of the very X-ray luminous clusters from the MAssive Cluster Survey (MACS). Using high-quality images taken with the Hubble Space Telescope (HST) that render measurement errors negligible, we find no radial galaxy alignment…
Supergranules as Probes of Solar Convection Zone Dynamics
Hathaway, David H.
Supergranules are convection cells seen at the Sun's surface as a space filling pattern of horizontal flows. While typical supergranules have diameters of about 35 Mm, they exhibit a broad spectrum of sizes from ~10 Mm to ~100 Mm. Here we show that supergranules of different sizes can be used to probe the rotation rate in the Sun's outer convectio…
Estimating distance, pressure, and dust opacity using submillimeter observations of self-gravitating filaments
Martin, P. G.; Fischera, J.
We present a detailed study of the surface brightness profiles of dense filaments in
Astrometric confirmation of young low-mass binaries and multiple systems in the Chamaeleon star-forming regions
Neuhäuser, R.; Schmidt, T. O. B.; Mugrauer, M. +4 more
Context. The star-forming regions in Chamaeleon (Cha) are one of the nearest (distance ~ 165 pc) and youngest (age ~ 2 Myr) conglomerates of recently formed stars and the ideal target for population studies of star formation.
Aims: We investigate a total of 16 Cha targets that have been suggested, but not confirmed, to be binaries or multiple…