Search Publications
On Relativistic Disk Spectroscopy in Compact Objects with X-ray CCD Cameras
Haberl, F.; Fabian, A. C.; Miller, J. M. +11 more
X-ray charge-coupled devices (CCDs) are the workhorse detectors of modern X-ray astronomy. Typically covering the 0.3-10.0 keV energy range, CCDs are able to detect photoelectric absorption edges and K shell lines from most abundant metals. New CCDs also offer resolutions of 30-50 (E/ΔE), which is sufficient to detect lines in hot plasmas and to r…
An Efficient Approximation of the Coronal Heating Rate for use in Global Sun-Heliosphere Simulations
Cranmer, Steven R.
The origins of the hot solar corona and the supersonically expanding solar wind are still the subject of debate. A key obstacle in the way of producing realistic simulations of the Sun-heliosphere system is the lack of a physically motivated way of specifying the coronal heating rate. Recent one-dimensional models have been found to reproduce many…
XMM-Newton Observations of HD 189733 During Planetary Transits
Knutson, H.; Pillitteri, I.; Henry, G. W. +4 more
We report on two XMM-Newton observations of the planetary host star HD 189733. The system has a close in planet and it can potentially affect the coronal structure via interactions with the magnetosphere. We have obtained X-ray spectra and light curves from EPIC and the Reflection Grating Spectrometer on board XMM-Newton which we have analyzed and…
Ultra-deep Mid-infrared Spectroscopy of Luminous Infrared Galaxies at z ~ 1 and z ~ 2
Veilleux, Sylvain; Wuyts, Stijn; Fadda, Dario +11 more
We present ultra-deep mid-infrared spectra of 48 infrared-luminous galaxies in the GOODS-south field obtained with the Infrared Spectrograph on the Spitzer Space Telescope. These galaxies are selected among faint infrared sources (0.14-0.5 mJy at 24 µm) in two redshift bins (0.76-1.05 and 1.75-2.4) to sample the major contributors to the cos…
Chandra Observations of 3C Radio Sources with z < 0.3: Nuclei, Diffuse Emission, Jets, and Hotspots
Macchetto, F. D.; Capetti, A.; Gilli, R. +11 more
We report on our Chandra Cycle 9 program to observe half of the 60 (unobserved by Chandra) 3C radio sources at z < 0.3 for 8 ks each. Here we give the basic data: the X-ray intensity of the nuclei and any features associated with radio structures such as hotspots and knots in jets. We have measured fluxes in soft, medium, and hard bands and are…
Panchromatic Observations and Modeling of the HV Tau C Edge-on Disk
Pinte, C.; Ménard, F.; Duchêne, G. +12 more
We present new high spatial resolution (lsim0farcs1) 1-5 µm adaptive optics images, interferometric 1.3 mm continuum and 12CO 2-1 maps, and 350 µm, 2.8 and 3.3 mm fluxes measurements of the HV Tau system. Our adaptive optics images unambiguously demonstrate that HV Tau AB-C is a common proper motion pair. They further reveal…
Micro-sigmoids as Progenitors of Coronal Jets: Is Eruptive Activity Self-similarly Multi-scaled?
Raouafi, N. -E.; Georgoulis, M. K.; Rust, D. M. +1 more
Observations from the X-ray telescope (XRT) on Hinode are used to study the nature of X-ray-bright points, sources of coronal jets. Several jet events in the coronal holes are found to erupt from small-scale, S-shaped bright regions. This finding suggests that coronal micro-sigmoids may well be progenitors of coronal jets. Moreover, the presence o…
Abundances and Density Structure of the Inner Circumstellar Ring Around SN 1987A
Fransson, Claes; Lundqvist, Peter; Mattila, Seppo +4 more
We present optical spectroscopic data of the inner circumstellar ring around supernova (SN) 1987A from the Anglo-Australian Telescope and the Very Large Telescope (VLT) between ~1400 and ~5000 days post-explosion. We also assembled the available optical and near-infrared line fluxes from the literature between ~300 and ~2000 days. These line light…
Streamer Waves Driven by Coronal Mass Ejections
Chen, Y.; Li, B.; Song, H. Q. +4 more
Between 2004 July 5 and July 7, two intriguing fast coronal mass ejection (CME)-streamer interaction events were recorded by the Large Angle and Spectrometric Coronagraph. At the beginning of the events, the streamer was pushed aside from its equilibrium position upon the impact of the rapidly outgoing and expanding ejecta; then, the streamer stru…
Improved Constraints on the Gravitational Lens Q0957+561. II. Strong Lensing
Keeton, C. R.; Bernstein, G. M.; Nakajima, R. +1 more
We present a detailed strong lensing analysis of a Hubble Space Telescope/Advanced Camera for Surveys legacy data set for the first gravitational lens, Q0957+561. With deep imaging we identify 24 new strongly lensed features, which we use to constrain mass models. We model the stellar component of the lens galaxy using the observed luminosity dist…