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Planck early results. XII. Cluster Sunyaev-Zeldovich optical scaling relations
Kneissl, R.; Dahle, H.; Miville-Deschênes, M. -A. +202 more
We present the Sunyaev-Zeldovich (SZ) signal-to-richness scaling relation (Y500 - N200) for the MaxBCG cluster catalogue. Employing a multi-frequency matched filter on the Planck sky maps, we measure the SZ signal for each cluster by adapting the filter according to weak-lensing calibrated mass-richness relations (N200
The Assembly History of Disk Galaxies. I. The Tully-Fisher Relation to z ~= 1.3 from Deep Exposures with DEIMOS
Treu, Tommaso; Ellis, Richard S.; Miller, Sarah H. +2 more
We present new measures of the evolving scaling relations between stellar mass, luminosity and rotational velocity for a morphologically inclusive sample of 129 disk-like galaxies with z AB < 22.5 in the redshift range 0.2 <z < 1.3, based on spectra from DEep Imaging Multi-Object Spectrograph on the Keck II telescope, multi-col…
Evolution of Coronal Holes and Implications for High-Speed Solar Wind During the Minimum Between Cycles 23 and 24
de Toma, G.
We analyze coronal holes present on the Sun during the extended minimum between Cycles 23 and 24, study their evolution, examine the consequences for the solar wind speed near the Earth, and compare it with the previous minimum in 1996. We identify coronal holes and determine their size and location using a combination of EUV observations from SOH…
Dust Heating Sources in Galaxies: The Case of M33 (HERM33ES)
Boquien, M.; Calzetti, D.; van der Werf, P. +8 more
Dust emission is one of the main windows to the physics of galaxies and to star formation as the radiation from young, hot stars is absorbed by the dust and reemitted at longer wavelengths. The recently launched Herschel satellite now provides a view of dust emission in the far-infrared at an unequaled resolution and quality up to 500 µm. In…
Bayesian inference of stellar parameters and interstellar extinction using parallaxes and multiband photometry
Bailer-Jones, C. A. L.
Astrometric surveys provide the opportunity to measure the absolute magnitudes of large numbers of stars, but only if the individual line-of-sight extinctions are known. Unfortunately, extinction is highly degenerate with stellar effective temperature when estimated from broad-band optical/infrared photometry. To address this problem, I introduce …
The composition and structure of the Enceladus plume
Hansen, C. J.; Hendrix, A. R.; West, R. A. +8 more
The Cassini Ultraviolet Imaging Spectrograph (UVIS) observed an occultation of the Sun by the water vapor plume at the south polar region of Saturn's moon Enceladus. The Extreme Ultraviolet (EUV) spectrum is dominated by the spectral signature of H2O gas, with a nominal line-of-sight column density of 0.90 ± 0.23 × 1016 cm
Redefinition of the crater-density and absolute-age boundaries for the chronostratigraphic system of Mars
Werner, S. C.; Tanaka, K. L.
For the boundaries of each chronostratigraphic epoch on Mars, we present systematically derived crater-size frequencies based on crater counts of geologic referent surfaces and three proposed "standard" crater size-frequency production distributions as defined by (a) a simple -2 power law, (b) Neukum and Ivanov, (c) Hartmann. In turn, these crater…
A Precise Cluster Mass Profile Averaged from the Highest-quality Lensing Data
Broadhurst, Tom; Zitrin, Adi; Coe, Dan +3 more
We outline our methods for obtaining high-precision mass profiles, combining independent weak-lensing distortion, magnification, and strong-lensing measurements. For massive clusters, the strong- and weak-lensing regimes contribute equal logarithmic coverage of the radial profile. The utility of high-quality data is limited by the cosmic noise fro…
The First Detection of Blue Straggler Stars in the Milky Way Bulge
Brown, Thomas M.; Anderson, Jay; Livio, Mario +8 more
We report the first detections of Blue Straggler Stars (BSS) in the bulge of the Milky Way. Proper motions from extensive space-based observations along a single sight line allow us to separate a sufficiently clean and well-characterized bulge sample such that we are able to detect a small population of bulge objects in the region of the color-mag…
The Strength and Radial Profile of the Coronal Magnetic Field from the Standoff Distance of a Coronal Mass Ejection-driven Shock
Gopalswamy, Nat; Yashiro, Seiji
We determine the coronal magnetic field strength in the heliocentric distance range 6-23 solar radii (Rs) by measuring the shock standoff distance and the radius of curvature of the flux rope during the 2008 March 25 coronal mass ejection imaged by white-light coronagraphs. Assuming the adiabatic index, we determine the Alfvén Mach number, and hen…