Search Publications
A Redshift Survey of Herschel Far-infrared Selected Starbursts and Implications for Obscured Star Formation
Berta, S.; Magnelli, B.; Lutz, D. +30 more
We present Keck spectroscopic observations and redshifts for a sample of 767 Herschel-SPIRE selected galaxies (HSGs) at 250, 350, and 500 µm, taken with the Keck I Low Resolution Imaging Spectrometer and the Keck II DEep Imaging Multi-Object Spectrograph. The redshift distribution of these SPIRE sources from the Herschel Multitiered Extragal…
Multi-wavelength View of Kiloparsec-scale Clumps in Star-forming Galaxies at z ~ 2
Ferguson, Henry C.; Giavalisco, Mauro; Koekemoer, Anton M. +2 more
This paper studies the properties of kiloparsec-scale clumps in star-forming galaxies at z ~ 2 through multi-wavelength broadband photometry. A sample of 40 clumps is identified from Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) z-band images through auto-detection and visual inspection from 10 galaxies with 1.5 < z < 2.5 in…
The Deflection of the Two Interacting Coronal Mass Ejections of 2010 May 23-24 as Revealed by Combined in Situ Measurements and Heliospheric Imaging
Möstl, C.; Farrugia, C. J.; Temmer, M. +4 more
In 2010 May 23-24, Solar Dynamics Observatory (SDO) observed the launch of two successive coronal mass ejections (CMEs), which were subsequently tracked by the SECCHI suite on board STEREO. Using the COR2 coronagraphs and the heliospheric imagers (HIs), the initial direction of both CMEs is determined to be slightly west of the Sun-Earth line. We …
Bipolar Magnetic Regions on the Sun: Global Analysis of the SOHO/MDI Data Set
Kosovichev, A. G.; Stenflo, J. O.
The magnetic flux that is generated by dynamo processes inside the Sun emerges in the form of bipolar magnetic regions. The properties of these directly observable signatures of the dynamo can be extracted from full-disk solar magnetograms. The most homogeneous, high-quality synoptic data set of solar magnetograms has been obtained with the Michel…
First Detection of Water Vapor in a Pre-stellar Core
Caselli, Paola; Codella, Claudio; Aikawa, Yuri +11 more
Water is a crucial molecule in molecular astrophysics as it controls much of the gas/grain chemistry, including the formation and evolution of more complex organic molecules in ices. Pre-stellar cores provide the original reservoir of material from which future planetary systems are built, but few observational constraints exist on the formation o…
No Clear Submillimeter Signature of Suppressed Star Formation among X-Ray Luminous Active Galactic Nuclei
Magnelli, B.; Altieri, B.; Daddi, E. +18 more
Many theoretical models require powerful active galactic nuclei (AGNs) to suppress star formation in distant galaxies and reproduce the observed properties of today's massive galaxies. A recent study based on Herschel-SPIRE submillimeter observations claimed to provide direct support for this picture, reporting a significant decrease in the mean s…
Quantifying Spicules
De Pontieu, Bart; Carlsson, Mats; Pereira, Tiago M. D.
Understanding the dynamic solar chromosphere is fundamental in solar physics. Spicules are an important feature of the chromosphere, connecting the photosphere to the corona, potentially mediating the transfer of energy and mass. The aim of this work is to study the properties of spicules over different regions of the Sun. Our goal is to investiga…
Disentangling Baryons and Dark Matter in the Spiral Gravitational Lens B1933+503
McKean, J. P.; Treu, T.; Auger, M. W. +10 more
Measuring the relative mass contributions of luminous and dark matter in spiral galaxies is important for understanding their formation and evolution. The combination of a galaxy rotation curve and strong lensing is a powerful way to break the disk-halo degeneracy that is inherent in each of the methods individually. We present an analysis of the …
Dwarfs Gobbling Dwarfs: A Stellar Tidal Stream around NGC 4449 and Hierarchical Galaxy Formation on Small Scales
Carballo-Bello, Julio A.; Romanowsky, Aaron J.; Brodie, Jean P. +13 more
A candidate diffuse stellar substructure was previously reported in the halo of the nearby dwarf starburst galaxy NGC 4449 by Karachentsev et al. We map and analyze this feature using a unique combination of deep integrated-light images from the BlackBird 0.5 m telescope, and high-resolution wide-field images from the 8 m Subaru Telescope, which r…
Hubble Space Telescope Reveals Multiple Sub-giant Branch in Eight Globular Clusters
Anderson, J.; Milone, A. P.; Marino, A. F. +6 more
In the last few years many globular clusters (GCs) have revealed complex color-magnitude diagrams, with the presence of multiple main sequences (MSs), broad or multiple sub-giant branches (SGBs) and MS turnoffs, and broad or split red giant branches (RGBs). After a careful correction for differential reddening, high-accuracy photometry with the Hu…