Search Publications
Estimating Luminosity Function Constraints from High-Redshift Galaxy Surveys
Robertson, Brant E.
The installation of the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST) will revolutionize the study of high-redshift galaxy populations. Initial observations of the HST Ultra Deep Field (UDF) have yielded multiple z >~ 7 dropout candidates. Supplemented by the GOODS Early Release Science (ERS) and further UDF pointings, these da…
Dust-temperature of an isolated star-forming cloud: Herschel observations of the Bok globule CB244
Henning, T.; Krause, O.; André, P. +6 more
We present Herschel observations of the isolated, low-mass star-forming Bok globule CB244. It contains two cold sources, a low-mass Class 0 protostar and a starless core, which is likely to be prestellar in nature, separated by 90" (~18 000 AU). The Herschel data sample the peak of the Planck spectrum for these sources, and are therefore ideal for…
A bright off-nuclear X-ray source: a type IIn supernova, a bright ULX or a recoiling supermassive black hole in CXOJ122518.6+144545
Fabian, A. C.; Miniutti, G.; Pooley, D. +3 more
In this paper we report the discovery of CXOJ122518.6+144545, a peculiar X-ray source with a position 3.6 +/- 0.2 arcsec off-nuclear from a Sloan Digital Sky Survey Data Release 7 (SDSS DR7) z = 0.0447 galaxy. The 3.6 arcsec offset corresponds to 3.2 kpc at the distance of the galaxy. The 0.3-8keV X-ray flux of this source is 5 × 10-14e…
The Last Eight-Billion Years of Intergalactic C IV Evolution
Prochaska, J. Xavier; Chen, Hsiao-Wen; Thom, Christopher +1 more
We surveyed the Hubble Space Telescope UV spectra of 49 low-redshift quasars for z < 1 C IV candidates, relying solely on the characteristic wavelength separation of the doublet. After consideration of the defining traits of C IV doublets (e.g., consistent line profiles, other associated transitions, etc.), we defined a sample of 38 definite (g…
Observations of Anisotropic Scaling of Solar Wind Turbulence
Wu, D. J.; Luo, Q. Y.
Using high-speed solar wind data recorded by the Ulysses spacecraft, we investigate and estimate the anisotropic inertial range scaling of the interplanetary magnetic field. We apply the method of the magnetic structure function (MSF), Sn (τ) = lang|b(t + τ) - b(t)| n rang vprop τζ(n), to analyze the scaling of sol…
A study of the interplay between ionized gas and star clusters in the central region of NGC 5253 with 2D spectroscopy
Walsh, J. R.; Monreal-Ibero, A.; Vílchez, J. M. +1 more
Context. Starbursts are one of the main contributors to the chemical enrichment of the interstellar medium. However, mechanisms governing the interaction between the recent star formation and the surrounding gas are not fully understood. Because of their a priori simplicity, the subgroup of H II galaxies constitute an ideal sample to study these m…
Radioactive 26Al from the Scorpius-Centaurus association
Wang, W.; Diehl, R.; Jean, P. +7 more
Context. The Scorpius-Centaurus association is the most-nearby group of massive and young stars. As nuclear-fusion products are ejected by massive stars and supernovae into the surrounding interstellar medium, the search for characteristic γ-rays from radioactivity is one way to probe the history of activity of such nearby massive stars on a My ti…
Evidence for Granulation in Early A-Type Stars
Kallinger, Thomas; Matthews, Jaymie M.
Stars with spectral types earlier than about F0 on (or close) to the main sequence have long been believed to lack observable surface convection, although evolutionary models of A-type stars do predict very thin surface convective zones. We present evidence for granulation in two δ Scuti stars of spectral type A2: HD 174936 and HD 50844. Recent an…
Seasonal change on Saturn from Cassini/CIRS observations, 2004-2009
Fletcher, Leigh N.; Achterberg, Richard K.; Irwin, Patrick G. J. +7 more
Five years of thermal infrared spectra from the Cassini Composite Infrared Spectrometer (CIRS) are analyzed to determine the response of Saturn's atmosphere to seasonal changes in insolation. Hemispheric mapping sequences at 15.0 cm -1 spectral resolution are used to retrieve the variation in the zonal mean temperatures in the stratosph…
Observations of a rotating macrospicule associated with an X-ray jet
Solanki, S. K.; Inhester, B.; Curdt, W. +2 more
Aims: We attempt to understand the driving mechanism of a macrospicule and its relationship with a coronal jet.
Methods: We study the dynamics of a macrospicule and an associated coronal jet captured by multi-spacecraft observations. Doppler velocities in both the macrospicule and the coronal jet are determined by EIS and SUMER spectra. …