Search Publications
Constraining dark matter properties with SPI
Boyarsky, Alexey; Ruchayskiy, Oleg; Malyshev, Denys +1 more
Using the high-resolution spectrometer SPI on board the International Gamma-Ray Astrophysics Laboratory (INTEGRAL), we search for a spectral line produced by a dark matter (DM) particle with a mass in the range 40keV < MDM < 14MeV, decaying in the DM halo of the Milky Way. To distinguish the DM decay line from numerous instrumenta…
Fluvial channels on Titan: Initial Cassini RADAR observations
Cassini RADAR Team; Kirk, Randolph L.; Lorenz, Ralph D. +13 more
Cassini radar images show a variety of fluvial channels on Titan's surface, often several hundreds of kilometers in length. Some (predominantly at low- and mid-latitude) are radar-bright and braided, resembling desert washes where fines have been removed by energetic surface liquid flow, presumably from methane rainstorms. Others (predominantly at…
Submillimeter Array Imaging of the CO(3-2) Line and 860 µm Continuum of Arp 220: Tracing the Spatial Distribution of Luminosity
Wilner, David J.; Zhang, Qizhou; Wang, Junzhi +6 more
We used the Submillimeter Array (SMA) to image 860 µm continuum and CO(3-2) line emission in the ultraluminous merging galaxy Arp 220, achieving a resolution of 0.23'' (80 pc) for the continuum and 0.33'' (120 pc) for the line. The CO emission peaks around the two merger nuclei with a velocity signature of gas rotation …
First Catalog of Strong Lens Candidates in the COSMOS Field
Refregier, Alexandre; Ellis, Richard; Schinnerer, Eva +19 more
We present the first catalog of 67 strong galaxy-galaxy lens candidates discovered in the 1.64 deg2 Hubble Space Telescope COSMOS survey. Twenty of these systems display multiple images or strongly curved large arcs. Our initial search is performed by visual inspection of the data and is restricted, for practical considerations, to mass…
Radial metallicity profiles for a large sample of galaxy clusters observed with XMM-Newton
Molendi, S.; Leccardi, A.
Aims: We measured radial metallicity profiles for a sample of ≈50 hot, intermediate redshift galaxy clusters, selected from the XMM-Newton archive.
Methods: As in our previous paper, we used background modeling rather than background subtraction, and the Cash statistic rather than the χ^2. This method requires a careful characterization of all…
Separating Baryons and Dark Matter in Cluster Cores: A Full Two-dimensional Lensing and Dynamic Analysis of Abell 383 and MS 2137-23
Smith, Graham P.; Treu, Tommaso; Ellis, Richard S. +2 more
We utilize existing data for the galaxy clusters MS 2137-23 and Abell 383 to present improved measures of the distribution of dark and baryonic material in the clusters' central regions. Our method, based on the combination of gravitational lensing and dynamical data, is uniquely capable of separating the distribution of dark and baryonic componen…
Observation of the hydrogen corona with SPICAM on Mars Express
Leblanc, F.; Bertaux, J. L.; Quémerais, E. +1 more
A series of seven dedicated Lyman- α observations of exospheric atomic hydrogen in the martian corona were performed in March 2005 with the ultraviolet spectrometer SPICAM on board Mars Express. Two types of observations are analyzed, observations at high illumination (for a solar zenith angle SZA equal to 30°) and observations at low illumination…
The Far Ultraviolet Spectroscopic Explorer Survey of O VI Absorption in the Disk of the Milky Way
Bowen, David V.; Tripp, Todd M.; Jenkins, Edward B. +12 more
To probe the distribution and physical characteristics of interstellar gas at temperatures T ≈ 3 × 105 K in the disk of the Milky Way, we have used the Far Ultraviolet Spectroscopic Explorer (FUSE) to observe absorption lines of O VI λ1032 toward 148 early-type stars situated at distances >1 kpc. After subtracting off a mild excess o…
Spatially Resolved Properties of the GRB 060505 Host: Implications for the Nature of the Progenitor
Fruchter, Andrew S.; Östlin, Göran; Hjorth, Jens +12 more
GRB 060505 was the first well-observed nearby possible long-duration gamma-ray burst (GRB) that had no associated supernova. Here we present spatially resolved spectra of the host galaxy of GRB 060505, an Sbc spiral, at redshift z = 0.0889. The GRB occurred inside a star-forming region in the northern spiral arm at 6.5 kpc from the center. From th…
Cassini plasma spectrometer thermal ion measurements in Saturn's inner magnetosphere
Thomsen, M. F.; Wilson, R. J.; Tokar, R. L. +3 more
Plasma data from the Cassini Plasma Spectrometer experiment are analyzed using a robust forward modeling technique for dayside equatorial orbits within the range 5.5 to 11 Saturn radii (1 RS = 60,268 km). It is assumed the measured ion data may be represented by two anisotropic Maxwellian distributed species, H+ and a water g…