Search Publications
GRB060218 as a Tidal Disruption of a White Dwarf by an Intermediate-mass Black Hole
Reynolds, Christopher S.; Shcherbakov, Roman V.; Pe'er, Asaf +3 more
The highly unusual pair of a gamma-ray burst (GRB) GRB060218 and an associated supernova, SN2006aj, has puzzled theorists for years. A supernova shock breakout and a jet from a newborn stellar mass compact object have been proposed to explain this pair's multiwavelength signature. Alternatively, we propose that the source is naturally explained by…
OTS 44: Disk and accretion at the planetary border
Liu, Y.; Bayo, A.; Wolf, S. +4 more
We discover that the very low-mass brown dwarf OTS 44 (M9.5, ~12 MJup) has significant accretion and a substantial disk, which demonstrates that the processes that accompany canonical star formation occur down to a central mass of a few Jupiter masses. We discover in VLT/SINFONI spectra that OTS 44 has strong, broad, and variable Pa β e…
A Herschel Survey of the [N II] 205 µm Line in Local Luminous Infrared Galaxies: The [N II] 205 µm Emission as a Star Formation Rate Indicator
Sanders, D. B.; Isaak, K. G.; Iwasawa, K. +16 more
We present, for the first time, a statistical study of [N II] 205 µm line emission for a large sample of local luminous infrared galaxies using Herschel Spectral and Photometric Imaging Receiver Fourier Transform Spectrometer (SPIRE FTS) data. For our sample of galaxies, we investigate the correlation between the [N II] luminosity (L [N…
Reverberation and Photoionization Estimates of the Broad-line Region Radius in Low-z Quasars
Sulentic, Jack W.; Marziani, Paola; Negrete, C. Alenka +1 more
Black hole mass estimation in quasars, especially at high redshift, involves the use of single-epoch spectra with signal-to-noise ratio and resolution that permit accurate measurement of the width of a broad line assumed to be a reliable virial estimator. Coupled with an estimate of the radius of the broad-line region (BLR) this yields the black h…
Protostars, multiplicity, and disk evolution in the Corona Australis region: a Herschel Gould Belt Study
Eiroa, C.; White, G. J.; Henning, T. +4 more
Context. The CrA region and the Coronet cluster form a nearby (138 pc), young (1-2 Myr) star-forming region that hosts a moderate population of Class I, II, and III objects.
Aims: We study the structure of the cluster and the properties of the protostars and protoplanetary disks in the region.
Methods: We present Herschel PACS photometry…
Discovery of Lyman Break Galaxies at z ~ 7 from the zFourGE Survey
Kelson, D. D.; Ferguson, H. C.; Finkelstein, S. L. +22 more
Star-forming galaxies at redshifts z > 6 are likely responsible for the reionization of the universe, and it is important to study the nature of these galaxies. We present three candidates for z ~ 7 Lyman break galaxies (LBGs) from a 155 arcmin2 area in the CANDELS/COSMOS field imaged by the deep FourStar Galaxy Evolution (zFourGE) s…
The SCUBA-2 Cosmology Legacy Survey: demographics of the 450-µm population
Smail, I.; Ivison, R. J.; van Kampen, E. +47 more
We investigate the multiwavelength properties of a sample of 450-µm-selected sources from the SCUBA-2 Cosmology Legacy Survey. A total of 69 sources were identified above 4σ in deep SCUBA-2 450-µm observations overlapping the UDS and COSMOS fields and covering 210 arcmin2 to a typical depth of σ450 = 1.5 mJy. Reli…
Observational evidence for dissociative shocks in the inner 100 AU of low-mass protostars using Herschel-HIFI
van Dishoeck, E. F.; Benz, A. O.; Bruderer, S. +3 more
Aims: Herschel-HIFI spectra of H2O towards low-mass protostars show a distinct velocity component not seen in observations from the ground of CO or other species. The aim is to characterise this component in terms of excitation conditions and physical origin.
Methods: A velocity component with an offset of ~10 km s-1
Polarimetry in the Hard X-Ray Domain with INTEGRAL SPI
Clark, D. J.; Jourdain, E.; Roques, J. P. +1 more
We present recent improvements in polarization analysis with the INTEGRAL SPI data. The SPI detector plane consists of 19 independent Ge crystals and can operate as a polarimeter. The anisotropy characteristics of Compton diffusions can provide information on the polarization parameters of the incident flux. By including the physics of the polariz…
Discovery of the magnetic field in the pulsating B star β Cephei
Talavera, A.; Donati, J. -F.; Kaper, L. +17 more
Context. Although the star itself is not helium enriched, the periodicity and the variability in the UV wind lines of the pulsating B1 IV star β Cephei are similar to what is observed in magnetic helium-peculiar B stars, suggesting that β Cep is magnetic.
Aims: We searched for a magnetic field using high-resolution spectropolarimetry. From UV…