Search Publications
Deep Chandra, HST-COS, and Megacam Observations of the Phoenix Cluster: Extreme Star Formation and AGN Feedback on Hundred Kiloparsec Scales
McNamara, Brian R.; Miller, Eric D.; Fabian, Andrew C. +17 more
We present new ultraviolet, optical, and X-ray data on the Phoenix galaxy cluster (SPT-CLJ2344-4243). Deep optical imaging reveals previously undetected filaments of star formation, extending to radii of ∼50-100 kpc in multiple directions. Combined UV-optical spectroscopy of the central galaxy reveals a massive (2 × 109 M⊙), …
X-Ray High-resolution Spectroscopy Reveals Feedback in a Seyfert Galaxy from an Ultra-fast Wind with Complex Ionization and Velocity Structure
Costantini, E.; Guainazzi, M.; Giroletti, M. +5 more
Winds outflowing from active galactic nuclei (AGNs) may carry significant amounts of mass and energy out to their host galaxies. In this paper we report the detection of a sub-relativistic outflow observed in the narrow line Seyfert 1 galaxy IRAS 17020+4544 as a series of absorption lines corresponding to at least five absorption components with a…
On the Temporal Evolution of Spicules Observed with IRIS, SDO, and Hinode
De Pontieu, B.; Rouppe van der Voort, L.; Pereira, T. M. D. +1 more
Spicules are ubiquitous, fast moving jets observed off-limb in chromospheric spectral lines. Combining the recently launched Interface Region Imaging Spectrograph with the Solar Dynamics Observatory and Hinode, we have a unique opportunity to study spicules simultaneously in multiple passbands and from a seeing free environment. This makes it poss…
Type IIb Supernova 2013df Entering into an Interaction Phase: A Link between the Progenitor and the Mass Loss
Folatelli, G.; Tanaka, M.; Phillips, M. M. +23 more
We report the late-time evolution of Type IIb supernova (SN IIb) 2013df. SN 2013df showed a dramatic change in its spectral features at ∼1 yr after the explosion. Early on it showed typical characteristics shared by SNe IIb/Ib/Ic dominated by metal emission lines, while later on it was dominated by broad and flat-topped Hα and He i emissions. The …
Hubble Tarantula Treasury Project. II. The Star-formation History of the Starburst Region NGC 2070 in 30 Doradus
Anderson, J.; Zaritsky, D.; Lennon, D. J. +10 more
We present a study of the recent star formation (SF) of 30 Doradus in the Large Magellanic Cloud (LMC) using the panchromatic imaging survey Hubble Tarantula Treasury Project. In this paper we focus on the stars within 20 pc of the center of 30 Doradus, the starburst region NGC 2070. We recovered the SF history by comparing deep optical and near-i…
Discovery of a Strongly Lensed Massive Quiescent Galaxy at z = 2.636: Spatially Resolved Spectroscopy and Indications of Rotation
Ellis, Richard S.; Belli, Sirio; Newman, Andrew B.
We report the discovery of RG1M0150, a massive, recently quenched galaxy at z = 2.636 that is multiply imaged by the cluster MACSJ0150.3-1005. We derive a stellar mass of {log}{M}*={11.49}-0.16+0.10 and a half-light radius of {R}e,{maj}=1.8+/- 0.4 {{kpc}}. Taking advantage of the lensing magnification, w…
Correlation between Galaxy Mergers and Luminous Active Galactic Nuclei
Ho, Luis C.; Im, Myungshin; Kim, Minjin +1 more
It is not yet clear what triggers the activity of active galactic nuclei (AGNs), but galaxy merging has been suspected to be one of the main mechanisms fueling the activity. Using deep optical images taken at various ground-based telescopes, we investigate the fraction of galaxy mergers in 39 luminous AGNs (MR ≲ -22.6 mag) at z ≤ 0.3 (a…
X-Ray and EUV Observations of Simultaneous Short and Long Period Oscillations in Hot Coronal Arcade Loops
Kumar, Pankaj; Cho, Kyung-Suk; Nakariakov, Valery M.
We report decaying quasi-periodic intensity oscillations in the X-ray (6-12 keV) and extreme-ultraviolet (EUV) channels (131, 94, 1600, 304 Å) observed by the Fermi Gamma-ray Burst Monitor and Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA), respectively, during a C-class flare. The estimated periods of oscillation and decay time in …
Magnetic Structure and Dynamics of the Erupting Solar Polar Crown Prominence on 2012 March 12
Reeves, Katharine K.; van Ballegooijen, Adriaan; DeLuca, Edward E. +3 more
We present an investigation of the polar crown prominence that erupted on 2012 March 12. This prominence is observed at the southeast limb by the Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA; end-on view) and displays a quasi-vertical thread structure. A bright U-shaped or horn-like structure is observed surrounding the upper…
NuSTAR Reveals Extreme Absorption in z < 0.5 Type 2 Quasars
Harrison, F. A.; Stern, D.; Zhang, W. W. +27 more
The intrinsic column density (NH) distribution of quasars is poorly known. At the high obscuration end of the quasar population and for redshifts z < 1, the X-ray spectra can only be reliably characterized using broad-band measurements that extend to energies above 10 keV. Using the hard X-ray observatory NuSTAR, along with archival …