Search Publications
Solar Magnetic Tracking. I. Software Comparison and Recommended Practices
Lamb, D. A.; DeForest, C. E.; Hagenaar, H. J. +2 more
Feature tracking and recognition are increasingly common tools for data analysis, but are typically implemented on an ad hoc basis by individual research groups, limiting the usefulness of derived results when selection effects and algorithmic differences are not controlled. Specific results that are affected include the solar magnetic turnover ti…
AEGIS: Enhancement of Dust-enshrouded Star Formation in Close Galaxy Pairs and Merging Galaxies up to z ~ 1
Weiner, Benjamin J.; Conselice, Christopher J.; Huang, J. -S. +13 more
Using data from the DEEP2 Galaxy Redshift Survey and HST/ACS imaging in the Extended Groth Strip, we select nearly 100 interacting galaxy systems, including kinematic close pairs and morphologically identified merging galaxies. Spitzer MIPS 24 µm fluxes of these systems reflect the current dusty star formation activity, and at a fixed stella…
A TRACE White Light and RHESSI Hard X-Ray Study of Flare Energetics
Fletcher, L.; Hannah, I. G.; Hudson, H. S. +1 more
In this paper we investigate the formation of the white-light (WL) continuum during solar flares and its relationship to energy deposition by electron beams inferred from hard X-ray emission. We analyze nine flares spanning GOES classifications from C4.8 to M9.1, seven of which show clear cospatial RHESSI hard X-ray and TRACE WL footpoints. We cha…
GRB 060505: A Possible Short-Duration Gamma-Ray Burst in a Star-forming Region at a Redshift of 0.09
Sharon, K.; Cenko, S. B.; Price, P. A. +26 more
On 2006 May 5, a 4 s duration, low-energy, ~1049 erg, gamma-ray burst (GRB) was observed, spatially associated with a z=0.0894 galaxy. Here we report the discovery of the GRB optical afterglow and observations of its environment using Gemini South, the Hubble Space Telescope (HST), Chandra, Swift, and the Very Large Array. The optical a…
Detection of [Ne II] Emission from Young Circumstellar Disks
Pascucci, I.; Carpenter, J. M.; Meyer, M. R. +9 more
We report the detection of [Ne II] emission at 12.81 µm in four out of the six optically thick dust disks observed as part of the FEPS Spitzer Legacy program. In addition, we detect a H I (7-6) emission line at 12.37 µm from the source RX J1852.3-3700. Detections of [Ne II] lines are favored by low mid-infrared excess emission. Both st…
Are ``EIT Waves'' Fast-Mode MHD Waves?
DeForest, C. E.; Stenflo, J. O.; Wills-Davey, M. J.
We examine the nature of large-scale, coronal, propagating wave fronts (``EIT waves'') and find they are incongruous with solutions using fast-mode MHD plane-wave theory. Specifically, we consider the following properties: nondispersive single pulse manifestations, observed velocities below the local Alfvén speed, and different pulses which travel…
Deep FORS1 Observations of the Double Main Sequence of ω Centauri
Pancino, E.; Bellazzini, M.; Origlia, L. +3 more
We present the results of a deep photometric survey performed with the VLT FORS1 aimed at investigating the complex main-sequence structure of the stellar system ω Centauri. We confirm the presence of a double main sequence and identify its blue component (bMS) over a large field of view up to 26' from the cluster center. We found that bMS stars a…
The Compact X-Ray Source 1E 1547.0-5408 and the Radio Shell G327.24-0.13: A New Proposed Association between a Candidate Magnetar and a Candidate Supernova Remnant
Gelfand, Joseph D.; Gaensler, B. M.
We present new observations of the field centered on X-ray source 1E 1547.0-5408. Analysis of a new Chandra observation shows that it is unresolved at arcsecond resolution, and analysis of a new XMM-Newton observation shows that its X-ray spectrum is best described by an absorbed power-law and blackbody model. A comparison of the X-ray flux observ…
Galactic Bulges from Hubble Space Telescope NICMOS Observations: Central Galaxian Objects, and Nuclear Profile Slopes
Balcells, Marc; Graham, Alister W.; Peletier, Reynier F.
We have measured the central structural properties for a sample of S0-Sbc galaxies down to scales of ~10 pc using Hubble Space Telescope NICMOS images. Central star clusters are found in 58% of our sample. Their near-infrared luminosities scale with the host bulge luminosities, as reported in 2003 by Balcells and coworkers. In terms of photometric…
AEGIS: Host Galaxy Morphologies of X-Ray-selected and Infrared-selected Active Galactic Nuclei at 0.2 <= z < 1.2
Barmby, P.; Cooper, M. C.; Lin, L. +16 more
We visually and quantitatively determine the host galaxy morphologies of 94 intermediate-redshift (0.2<=z<1.2) active galactic nuclei (AGNs), selected using Chandra X-ray data and Spitzer mid-infrared data in the Extended Groth Strip. Using recently developed morphology measures, the second-order moment of the brightest 20% of a galaxy's flu…