Search Publications
The Extragalactic Distance Database: Color-Magnitude Diagrams
Shaya, Edward J.; Tully, R. Brent; Makarov, Dmitry I. +3 more
The color-magnitude diagrams/tip of the red giant branch (CMDs/TRGB) section of the Extragalactic Distance Database contains a compilation of observations of nearby galaxies from the Hubble Space Telescope. Approximately 250 (and increasing) galaxies in the Local Volume have CMDs and the stellar photometry tables used to produce them available thr…
Bulge and Clump Evolution in Hubble Ultra Deep Field Clump Clusters, Chains and Spiral Galaxies
Elmegreen, Bruce G.; Elmegreen, Debra Meloy; Fernandez, Maria Ximena +1 more
Clump clusters and chain galaxies in the Hubble Ultra Deep Field (UDF) are examined for bulges in Near-Infrared Camera Multi-Object Spectrometer images. Approximately 50% of the clump clusters and 30% of the chains have relatively red and massive clumps that could be young bulges. Magnitudes and colors are determined for these bulgelike objects an…
Water, Methane, and Carbon Dioxide Present in the Dayside Spectrum of the Exoplanet HD 209458b
Burrows, A.; Tinetti, G.; Bouwman, J. +11 more
Using the NICMOS instrument on the Hubble Space Telescope, we have measured the dayside spectrum of HD 209458b between 1.5 and 2.5 µm. The emergent spectrum is dominated by features due to the presence of methane (CH4) and water vapor (H2O), with smaller contributions from carbon dioxide (CO2). Combining this…
Radial evolution of nonthermal electron populations in the low-latitude solar wind: Helios, Cluster, and Ulysses Observations
Maksimovic, Milan; Štverák, Štěpán; Marsch, Eckart +3 more
We have performed a statistical study of a substantial amount of solar wind electron velocity distribution functions (eVDFs). In our data set, we combine measurements acquired onboard three spacecrafts (Helios, Cluster II, and Ulysses) in the low ecliptic latitudes covering the heliocentric distance from 0.3 up to 4 AU. In this study, we focus on …
CAIXA: a catalogue of AGN in the XMM-Newton archive. I. Spectral analysis
Bianchi, S.; Ponti, G.; Guainazzi, M. +2 more
Aims: We present CAIXA, a Catalogue of AGN In the XMM-Newton Archive. It consists of all the radio-quiet X-ray unobscured (N_H<2×1022 cm-2) active galactic nuclei (AGN) observed by XMM-Newton in targeted observations, whose data are public as of March 2007. With its 156 sources, this is the largest catalogue of high signal…
Stellar-Mass Black Hole Spin Constraints from Disk Reflection and Continuum Modeling
Fabian, A. C.; Miller, J. M.; Reynolds, C. S. +2 more
Accretion disk reflection spectra, including broad iron emission lines, bear the imprints of the strong Doppler shifts and gravitational redshifts close to black holes. The extremity of these shifts depends on the proximity of the innermost stable circular orbit to the black hole, and that orbit is determined by the black hole spin parameter. Mode…
GRB 080913 at Redshift 6.7
Greiner, J.; McBreen, S.; Hartmann, D. H. +44 more
We report on the detection by Swift of GRB 080913, and subsequent optical/near-infrared follow-up observations by GROND, which led to the discovery of its optical/NIR afterglow and the recognition of its high-z nature via the detection of a spectral break between the i' and z' bands. Spectroscopy obtained at the ESO-VLT revealed a continuum extend…
Radar evidence for ice in lobate debris aprons in the mid-northern latitudes of Mars
Head, James W.; Frigeri, Alessandro; Seu, Roberto +5 more
Subsurface radar sounding data indicate that lobate debris aprons found in Deuteronilus Mensae in the mid-northern latitudes of Mars are composed predominantly of water ice. The position in time delay and the relatively low amount of signal loss of the apparent basal reflectors below the debris aprons indicate that aprons contain only a minor comp…
Dependence of Solar-Wind Power Spectra on the Direction of the Local Mean Magnetic Field
Podesta, J. J.
Wavelet analysis can be used to measure the power spectrum of solar-wind fluctuations along a line in any direction (θ, phi) with respect to the local mean magnetic field B 0. This technique is applied to study solar-wind turbulence in high-speed streams in the ecliptic plane near solar minimum using magnetic field measurements with a c…
Quantifying the coexistence of massive black holes and dense nuclear star clusters
Spitler, Lee R.; Graham, Alister W.
In large spheroidal stellar systems, such as elliptical galaxies, one invariably finds a 106-109Msolar supermassive black hole at their centre. In contrast, within dwarf elliptical galaxies one predominantly observes a 105-107Msolar nuclear star cluster. To date, few galaxies have b…