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The Lyα Line Profiles of Ultraluminous Infrared Galaxies: Fast Winds and Lyman Continuum Leakage
DOI: 10.1088/0004-637X/803/1/6 Bibcode: 2015ApJ...803....6M

Martin, Crystal L.; Henry, Alaina; Danforth, Charles W. +3 more

We present new Hubble Space Telescope Cosmic Origins Spectrograph far-ultraviolet (far-UV) spectroscopy and Keck Echellete optical spectroscopy of 11 ultraluminous infrared galaxies (ULIRGs), a rare population of local galaxies experiencing massive gas inflows, extreme starbursts, and prominent outflows. We detect Lyα emission from eight ULIRGs an…

2015 The Astrophysical Journal
eHST 72
Current Sheets in the Earth Magnetotail: Plasma and Magnetic Field Structure with Cluster Project Observations
DOI: 10.1007/s11214-014-0126-7 Bibcode: 2015SSRv..188..311P

Nakamura, Rumi; Zelenyi, Lev; Artemyev, Anton +2 more

Thin current sheets having kinetic scales are an important plasma structure, where the magnetic energy dissipation and charged particle acceleration are the most effective. It is believed that such current sheets are self-consistently formed by the specific nonadiabatic dynamics of charged particles and play a critical role in many space plasma an…

2015 Space Science Reviews
Cluster 72
No evidence for significant age spreads in young massive LMC clusters
DOI: 10.1051/0004-6361/201424455 Bibcode: 2015A&A...575A..62N

Bastian, N.; Niederhofer, F.; Silva-Villa, E. +1 more

Recent discoveries have put the picture of stellar clusters being simple stellar populations into question. In particular, the color-magnitude diagrams of intermediate age (1-2 Gyr) massive clusters in the Large Magellanic Cloud (LMC) show features that could be interpreted as age spreads of 100-500 Myr. If multiple generations of stars are presen…

2015 Astronomy and Astrophysics
eHST 72
Metal Deficiency in Cluster Star-Forming Galaxies At Z = 2
DOI: 10.1088/0004-637X/801/2/132 Bibcode: 2015ApJ...801..132V

Daddi, E.; Bournaud, F.; Juneau, S. +8 more

We investigate the environmental effect on the metal enrichment of star-forming galaxies (SFGs) in the farthest spectroscopically confirmed and X-ray-detected cluster, CL J1449+0856 at z = 1.99. We combined Hubble Space Telescope/WFC3 G141 slitless spectroscopic data, our thirteen-band photometry, and a recent Subaru/Multi-object InfraRed Camera a…

2015 The Astrophysical Journal
eHST 72
Structure and Formation of cD Galaxies: NGC 6166 in ABELL 2199
DOI: 10.1088/0004-637X/807/1/56 Bibcode: 2015ApJ...807...56B

Kormendy, John; Bender, Ralf; Fisher, David B. +1 more

Hobby-Eberly Telescope (HET) spectroscopy is used to measure the velocity dispersion profile of the nearest prototypical cD galaxy, NGC 6166 in the cluster Abell 2199. We also present composite surface photometry from many telescopes. We confirm the defining feature of a cD galaxy; i.e., (we suggest), a halo of stars that fills the cluster center …

2015 The Astrophysical Journal
eHST 72
Quasi-periodic Pulsations in Solar and Stellar Flares: Re-evaluating their Nature in the Context of Power-law Flare Fourier Spectra
DOI: 10.1088/0004-637X/798/2/108 Bibcode: 2015ApJ...798..108I

Dominique, M.; Ireland, J.; Inglis, A. R.

The nature of quasi-periodic pulsations (QPPs) in solar and stellar flares remains debated. Recent work has shown that power-law-like Fourier power spectra are an intrinsic property of solar and stellar flare signals, a property that many previous studies of this phenomenon have not accounted for. Hence a re-evaluation of the existing interpretati…

2015 The Astrophysical Journal
PROBA-2 72
The formation of NGC 3603 young starburst cluster: `prompt' hierarchical assembly or monolithic starburst?
DOI: 10.1093/mnras/stu2445 Bibcode: 2015MNRAS.447..728B

Kroupa, Pavel; Banerjee, Sambaran

The formation of very young massive clusters or `starburst' clusters is currently one of the most widely debated topic in astronomy. The classical notion dictates that a star cluster is formed in situ in a dense molecular gas clump. The stellar radiative and mechanical feedback to the residual gas energizes the latter until it escapes the system. …

2015 Monthly Notices of the Royal Astronomical Society
eHST 72
On the 2012 October 23 Circular Ribbon Flare: Emission Features and Magnetic Topology
DOI: 10.1088/0004-637X/806/2/171 Bibcode: 2015ApJ...806..171Y

Ding, M. D.; Yang, Kai; Guo, Yang

Circular ribbon flares are usually related to spine-fan type magnetic topology containing null points. In this paper, we investigate an X-class circular ribbon flare on 2012 October 23, using the multiwavelength data from the Solar Dynamics Observatory, Hinode, and RHESSI. In Ca ii H emission, the flare showed three ribbons with two highly elongat…

2015 The Astrophysical Journal
Hinode 72
A NuSTAR Survey of Nearby Ultraluminous Infrared Galaxies
DOI: 10.1088/0004-637X/814/1/56 Bibcode: 2015ApJ...814...56T

Hailey, Charles J.; Alexander, D. M.; Koss, Michael +17 more

We present a Nuclear Spectroscopic Telescope Array (NuSTAR), Chandra, and XMM-Newton survey of nine of the nearest ultraluminous infrared galaxies (ULIRGs). The unprecedented sensitivity of NuSTAR at energies above 10 keV enables spectral modeling with far better precision than was previously possible. Six of the nine sources observed were detecte…

2015 The Astrophysical Journal
XMM-Newton 72
Quenching and morphological transformation in semi-analytic models and CANDELS
DOI: 10.1093/mnras/stv1007 Bibcode: 2015MNRAS.451.2933B

Papovich, Casey; Barro, Guillermo; Bell, Eric F. +9 more

We examine the spheroid growth and star formation quenching experienced by galaxies since z ∼ 3 by studying the evolution with redshift of the quiescent and spheroid-dominated fractions of galaxies from the CANDELS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey) and GAMA (Galaxy and Mass Assembly) surveys. We compare the observed …

2015 Monthly Notices of the Royal Astronomical Society
eHST 72