Search Publications
Molecular Gas Heating Mechanisms, and Star Formation Feedback in Merger/Starbursts: NGC 6240 and Arp 193 as Case Studies
Greve, T. R.; van der Werf, Paul; Zhang, Zhi-Yu +6 more
We used the SPIRE/FTS instrument aboard the Herschel Space Observatory to obtain the Spectral Line Energy Distributions (SLEDs) of CO from J = 4-3 to J = 13-12 of Arp 193 and NGC 6240, two classical merger/starbursts selected from our molecular line survey of local Luminous Infrared Galaxies (L IR >= 1011 L ⊙). …
The Mrk 231 molecular outflow as seen in OH
Lutz, D.; Poglitsch, A.; Sturm, E. +12 more
We report on the Herschel/PACS observations of OH in Mrk 231, with detections in nine doublets observed within the PACS range, and present radiative-transfer models for the outflowing OH. Clear signatures of outflowing gas are found in up to six OH doublets with different excitation requirements. At least two outflowing components are identified, …
Ionization compression impact on dense gas distribution and star formation. Probability density functions around H II regions as seen by Herschel
Hill, T.; White, G. J.; André, Ph. +22 more
Aims: Ionization feedback should impact the probability distribution function (PDF) of the column density of cold dust around the ionized gas. We aim to quantify this effect and discuss its potential link to the core and initial mass function (CMF/IMF).
Methods: We used Herschel column density maps of several regions observed within the …
Comparative Study of MHD Modeling of the Background Solar Wind
Temmer, M.; Veronig, A. M.; Riley, P. +4 more
Knowledge about the background solar wind plays a crucial role in the framework of space-weather forecasting. In-situ measurements of the background solar wind are only available for a few points in the heliosphere where spacecraft are located, therefore we have to rely on heliospheric models to derive the distribution of solar-wind parameters in …
"TNOs are Cool": A survey of the trans-Neptunian region. X. Analysis of classical Kuiper belt objects from Herschel and Spitzer observations
Fornasier, S.; Pál, A.; Lellouch, E. +14 more
Context. The Kuiper belt is formed of planetesimals which failed to grow to planets and its dynamical structure has been affected by Neptune. The classical Kuiper belt contains objects both from a low-inclination, presumably primordial, distribution and from a high-inclination dynamically excited population.
Aims: Based on a sample of classic…
Three Ancient Halo Subgiants: Precise Parallaxes, Compositions, Ages, and Implications for Globular Clusters
Schaefer, Gail H.; Nelan, Edmund P.; Bond, Howard E. +3 more
The most accurate ages for the oldest stars are those obtained for nearby halo subgiants because they depend almost entirely on just the measured parallaxes and absolute oxygen abundances. In this study, we have used the Fine Guidance Sensors on the Hubble Space Telescope to determine trigonometric parallaxes, with precisions of 2.1% or better, fo…
The Absolute Calibration of the EUV Imaging Spectrometer on Hinode
Landi, Enrico; Warren, Harry P.; Ugarte-Urra, Ignacio
We investigate the absolute calibration of the EUV Imaging Spectrometer (EIS) on Hinode by comparing EIS full-disk mosaics with irradiance observations from the EUV Variability Experiment on the Solar Dynamics Observatory. We also use extended observations of the quiet corona above the limb combined with a simple differential emission measure mode…
The SAMI Pilot Survey: the kinematic morphology-density relation in Abell 85, Abell 168 and Abell 2399
Bland-Hawthorn, Joss; Konstantopoulos, Iraklis S.; Brough, S. +17 more
We examine the kinematic morphology of early-type galaxies (ETGs) in three galaxy clusters Abell 85, 168 and 2399. Using data from the Sydney-AAO Multi-object Integral field spectrograph we measure spatially resolved kinematics for 79 ETGs in these clusters. We calculate λR, a proxy for the projected specific stellar angular momentum, f…
Hubble Space Telescope/Advanced Camera for Surveys Confirmation of the Dark Substructure in A520
Hoekstra, H.; Jee, M. J.; Mahdavi, A. +1 more
We present a weak-lensing study of the cluster A520 based on Advanced Camera for Surveys (ACS) data. The excellent data quality provides a mean source density of ~109 arcmin-2, which improves both resolution and significance of the mass reconstruction compared to a previous study based on Wide Field Planetary Camera 2 (WFPC2) images. We…
GRB 130925A: an ultralong gamma ray burst with a dust-echo afterglow, and implications for the origin of the ultralong GRBs
Lien, A.; Sánchez-Ramírez, R.; Götz, D. +24 more
GRB 130925A was an unusual gamma ray burst (GRB), consisting of three distinct episodes of high-energy emission spanning ∼20 ks, making it a member of the proposed category of `ultralong' bursts. It was also unusual in that its late-time X-ray emission observed by Swift was very soft, and showed a strong hard-to-soft spectral evolution with time. …