Search Publications
An Integrated Model for the Production of X-Ray Time Lags and Quiescent Spectra from Homogeneous and Inhomogeneous Black Hole Accretion Coronae
Becker, Peter A.; Kroon, John J.
Many accreting black holes manifest time lags during outbursts, in which the hard Fourier component typically lags behind the soft component. Despite decades of observations of this phenomenon, the underlying physical explanation for the time lags has remained elusive, although there are suggestions that Compton reverberation plays an important ro…
Possible gamma-ray burst radio detections by the Square Kilometre Array. New perspectives
Capozziello, Salvatore; Ruggeri, Alan Cosimo
The next generation interferometric radio telescope, the Square Kilometre Array (SKA), which will be the most sensitive and largest radio telescope ever constructed, could greatly contribute to the detection, survey and characterization of Gamma Ray Bursts (GRBs). By the SKA, it will be possible to perform the follow up of GRBs even for several mo…
New Gapless COS G140L Mode Proposed for Background-limited Far-UV Observations
Anderson, Scott F.; France, Kevin; Fleming, Brian +6 more
Here we describe the observation and calibration procedure for a new G140L observing mode for the Cosmic Origins Spectrograph (COS) on board the Hubble Space Telescope (HST). This mode, CENWAV = 800, is designed to move the far-UV band fully onto the Segment A detector, allowing for more efficient observation and analysis by simplifying calibratio…
The structure and early evolution of massive star forming regions. Substructure in the infrared dark cloud SDC13
Avison, A.; Peretto, N.; Fuller, G. A. +4 more
Context. Investigations into the substructure of massive star forming regions are essential for understanding the observed relationships between core mass distributions and mass distributions in stellar clusters, differentiating between proposed mechanisms of massive star formation.
Aims: We study the substructure in the two largest fragments…
How Accurate Are Infrared Luminosities from Monochromatic Photometric Extrapolation?
Fang, Guanwen; Lin, Zesen; Kong, Xu
Template-based extrapolations from only one photometric band can be a cost-effective method to estimate the total infrared (IR) luminosities ({L}{IR}) of galaxies. By utilizing multi-wavelength data that covers across 0.35-500 µm in GOODS-North and GOODS-South fields, we investigate the accuracy of this monochromatic extrapolated …
Large-scale latitude distortions of the inner Milky Way disk from the Herschel/Hi-GAL Survey
Moore, T. J. T.; Testi, L.; Benedettini, M. +9 more
Aims: We use the Herschel Hi-GAL survey data to study the spatial distribution in Galactic longitude and latitude of the interstellar medium (ISM) and of dense, star-forming clumps in the inner Galaxy.
Methods: We assemble a complete mosaic of the inner Galaxy between l = -70° and +68° in the far-infrared continuum from Hi-GAL. The peak …
Low-end mass function of the Quintuplet cluster
Kim, Sungsoo S.; Shin, Jihye
The Quintuplet and Arches clusters, which were formed in the harsh environment of the Galactic Centre (GC) a few million years ago, have been excellent targets for studying the effects of a star-forming environment on the initial mass function (IMF). In order to estimate the shape of the low-end IMF of the Arches cluster, Shin & Kim devised a …
Compact stellar systems in the polar ring galaxies NGC 4650A and NGC 3808B: Clues to polar disk formation
Georgiev, Iskren Y.; Goudfrooij, Paul; Puzia, Thomas H. +2 more
Context. Polar ring galaxies (PRGs) are composed of two kinematically distinct and nearly orthogonal components, a host galaxy (HG) and a polar ring/disk (PR). The HG usually contains an older stellar population than the PR. The suggested formation channel of PRGs is still poorly constrained. Suggested options are merger, gas accretion, tidal inte…
A simple model for understanding the DIM dust measurement at comet 67P/Churyumov-Gerasimenko
Flandes, Alberto; Krüger, Harald; Della Corte, Vincenzo +1 more
We present a simple model for gas and dust flow from 67P/Churyumov-Gerasimenko that can be used to understand the grain impact observed by the DIM instrument on Philae (Krüger et al., 2015). We show how model results when applied to the GIADA measurements (Rotundi et al., 2015; Della Corte et al., 2015) can be used, in conjunction with the results…
The Gray Extinction of the Ionizing Cluster in NGC 3603 from Ultraviolet to Optical Wavelengths
Grebel, Eva K.; Pang, Xiaoying; Pasquali, Anna
We use photometry in the F220W, F250W, F330W, F435W filters from the High Resolution Channel of the Advanced Camera for Surveys and photometry in the F555W, F675W, and F814W filters from the Wide Field and Planetary Camera 2 aboard the Hubble Space Telescope to derive individual stellar reddenings and extinctions for stars in the HD 97950 cluster …