Search Publications
Herschel/HIFI Observations of Hydrogen Fluoride Toward Sagittarius B2(M)
Lis, D. C.; Bergin, E. A.; Phillips, T. G. +6 more
Herschel/HIFI observations have revealed the presence of widespread absorption by hydrogen fluoride (HF) J = 1-0 rotational transition, toward a number of Galactic sources. We present observations of HF J = 1-0 toward the high-mass star-forming region Sagittarius B2(M). The spectrum obtained shows a complex pattern of absorption, with numerous fea…
Ejecta Knot Flickering, Mass Ablation, and Fragmentation in Cassiopeia A
Shull, J. Michael; Fesen, Robert A.; Hammell, Molly C. +2 more
Ejecta knot flickering, ablation tails, and fragmentation are expected signatures associated with the gradual dissolution of high-velocity supernova (SN) ejecta caused by their passage through an inhomogeneous circumstellar medium or interstellar medium (ISM). Such phenomena mark the initial stages of the gradual merger of SN ejecta with and the e…
PTF 10bzf (SN 2010ah): A Broad-line Ic Supernova Discovered by the Palomar Transient Factory
Cenko, S. B.; Mitrofanov, I.; Bloom, J. S. +26 more
We present the discovery and follow-up observations of a broad-line Type Ic supernova (SN), PTF 10bzf (SN 2010ah), detected by the Palomar Transient Factory (PTF) on 2010 February 23. The SN distance is cong218 Mpc, greater than GRB 980425/SN 1998bw and GRB 060218/SN 2006aj, but smaller than the other SNe firmly associated with gamma-ray bursts (G…
The Extremely Red Host Galaxy of GRB 080207
Cresci, Giovanni; Savaglio, Sandra; Pian, Elena +5 more
We present optical, near-infrared, and Spitzer IRAC and MIPS observations of the host galaxy of the dark Swift gamma-ray burst GRB 080207. The host is faint, with extremely red optical-infrared colors (R - K = 6.3, 24 µm/R-band flux ~1000) making it an extremely red object (ERO) and a dust-obscured galaxy (DOG). The spectral energy distribut…
The Young Binary DQ Tau: A Hunt for X-ray Emission from Colliding Magnetospheres
Garmire, Gordon P.; Broos, Patrick S.; Getman, Konstantin V. +2 more
The young high-eccentricity binary DQ Tau exhibits powerful recurring millimeter-band (mm) flaring attributed to collisions between the two stellar magnetospheres near periastron, when the stars are separated by only ~8 R sstarf. These magnetospheric interactions are expected to have scales and magnetic field strengths comparable to tho…
Spectral Properties of Regions and Structures in the Interstellar Boundary Explorer (IBEX) Sky Maps
Reisenfeld, D. B.; McComas, D. J.; Schwadron, N. A. +5 more
We study the spectral properties of different regions and structures in the energetic neutral atom (ENA) maps at energies from ~0.5 keV to ~6 keV from the Interstellar Boundary Explorer (IBEX) mission. We find that (1) an ankle-shaped break (spectrum hardens) between ~1 keV and ~2 keV characterizes the polar spectra and the right flank, while a kn…
PDR Model Mapping of Physical Conditions via Spitzer/IRS Spectroscopy of H2: Theoretical Success toward NGC 2023-South
Wolfire, M. G.; Sheffer, Y.; Hollenbach, D. J. +2 more
We use the Infrared Spectrograph on Spitzer to observe the southern part of the reflection nebula NGC 2023, including the Southern Ridge, which is a photodissociation region (PDR) par excellence excited by HD 37903. Five pure-rotational H2 emission lines are detected and mapped over and around the Southern Ridge in order to compare with…
EUV Spectral Line Formation and the Temperature Structure of Active Region Fan Loops: Observations with Hinode/EIS and SDO/AIA
Warren, Harry P.; Young, Peter R.; Brooks, David H.
With the aim of studying active region fan loops using observations from the Hinode EUV Imaging Spectrometer (EIS) and Solar Dynamics Observatory Atmospheric Imaging Assembly (AIA), we investigate a number of inconsistencies in modeling the absolute intensities of Fe VIII and Si VII lines, and address why spectroheliograms formed from these lines …
Galactic-scale Absorption Outflow in the Low-luminosity Quasar IRAS F04250-5718: Hubble Space Telescope/Cosmic Origins Spectrograph Observations
Kriss, Gerard A.; Kaastra, Jelle; Behar, Ehud +17 more
We present absorption line analysis of the outflow in the quasar IRAS F04250-5718. Far-ultraviolet data from the Cosmic Origins Spectrograph on board the Hubble Space Telescope reveal intrinsic narrow absorption lines from high ionization ions (e.g., C IV, N V, and O VI) as well as low ionization ions (e.g., C II and Si III). We identify three kin…
SWAP-SECCHI Observations of a Mass-loading Type Solar Eruption
Berghmans, David; Mierla, Marilena; Zhukov, Andrei N. +2 more
We present a three-dimensional reconstruction of an eruption that occurred on 2010 April 3 using observations from SWAP on board PROBA2 and SECCHI on board STEREO. The event unfolded in two parts: an initial flow of cooler material confined to a height low in the corona, followed by a flux rope eruption higher in the corona. We conclude that mass …