Search Publications
New Optical/Ultraviolet Counterparts and the Spectral Energy Distributions of Nearby, Thermally Emitting, Isolated Neutron Stars
van Kerkwijk, M. H.; Kaplan, D. L.; Ho, W. C. G. +1 more
We present Hubble Space Telescope optical and ultraviolet photometry for five nearby, thermally emitting neutron stars. With these measurements, all seven such objects have confirmed optical and ultraviolet counterparts. Combining our data with archival space-based photometry, we present spectral energy distributions for all sources and measure th…
X-Ray Spectral Constraints for z ≈ 2 Massive Galaxies: The Identification of Reflection-dominated Active Galactic Nuclei
Daddi, E.; Lehmer, B. D.; Alexander, D. M. +18 more
We use the 4 Ms Chandra Deep Field-South (CDF-S) survey to place direct constraints on the ubiquity of z ≈ 2 heavily obscured active galactic nuclei (AGNs) in K < 22 BzK-selected galaxies. Forty-seven (≈21%) of the 222 BzK-selected galaxies in the central region of the CDF-S are detected at X-ray energies, 11 (≈5%) of which have hard X-ray spec…
XMM-Newton X-ray and Ultraviolet Observations of the Fast Nova V2491 Cyg during the Supersoft Source Phase
Ness, J. -U.; Hernanz, M.; Sala, G. +12 more
Two XMM-Newton observations of the fast classical nova V2491 Cyg were carried out in short succession on days 39.93 and 49.62 after discovery, during the supersoft source (SSS) phase, yielding simultaneous X-ray and UV light curves and high-resolution X-ray spectra. The first X-ray light curve is highly variable, showing oscillations with a period…
X-Ray Spectroscopy of the High-mass X-Ray Binary Pulsar Centaurus X-3 over Its Binary Orbit
Paul, Biswajit; Naik, Sachindra; Ali, Zulfikar
We present a comprehensive spectral analysis of the high-mass X-ray binary (HMXB) pulsar Centaurus X-3 with the Suzaku observatory covering nearly one orbital period. The light curve shows the presence of extended dips which are rarely seen in HMXBs. These dips are seen up to as high as ~40 keV. The pulsar spectra during the eclipse, out-of-eclips…
A CANDELS WFC3 Grism Study of Emission-line Galaxies at z ~ 2: A Mix of Nuclear Activity and Low-metallicity Star Formation
Finkelstein, Steven L.; Bell, Eric F.; Dickinson, Mark +26 more
We present Hubble Space Telescope Wide Field Camera 3 (WFC3) slitless grism spectroscopy of 28 emission-line galaxies at z ~ 2, in the GOODS-S region of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey. The high sensitivity of these grism observations, with >1σ detections of emission lines to f > 2.5 × 10-18 erg …
Magnetoseismological Determination of Magnetic Field and Plasma Density Height Variation in a Solar Spicule
Goossens, M.; Verth, G.; He, J. -S.
The variation of magnetic field strength and plasma density along a solar spicule is determined by the use of magnetoseismology. From Solar Optical Telescope observations of a kink wave propagating along a spicule, by estimating the spatial change in phase speed and velocity amplitude, a novel approach is demonstrated to determine the chromospheri…
The Sloan Lens ACS Survey. XI. Beyond Hubble Resolution: Size, Luminosity, and Stellar Mass of Compact Lensed Galaxies at Intermediate Redshift
Treu, Tommaso; Marshall, Philip J.; Auger, Matthew W. +5 more
We exploit the strong lensing effect to explore the properties of intrinsically faint and compact galaxies at intermediate redshift (z s ~= 0.4-0.8) at the highest possible resolution at optical wavelengths. Our sample consists of 46 strongly lensed emission line galaxies (ELGs) discovered by the Sloan Lens ACS Survey (SLACS). The galax…
Arrival Time Calculation for Interplanetary Coronal Mass Ejections with Circular Fronts and Application to STEREO Observations of the 2009 February 13 Eruption
Luhmann, J. G.; Zhang, T. L.; Möstl, C. +11 more
One of the goals of the NASA Solar TErestrial RElations Observatory (STEREO) mission is to study the feasibility of forecasting the direction, arrival time, and internal structure of solar coronal mass ejections (CMEs) from a vantage point outside the Sun-Earth line. Through a case study, we discuss the arrival time calculation of interplanetary C…
How Typical Are the Local Group Dwarf Galaxies?
McQuinn, Kristen B. W.; Dolphin, Andrew E.; Skillman, Evan D. +11 more
We compare the cumulative star formation histories (SFHs) of Local Group (LG) dwarf galaxies with those in the volume-limited ACS Nearby Galaxy Survey Treasury (ANGST) sample (D <~ 4 Mpc), in order to understand how typical the LG dwarf galaxies are relative to those in the nearby universe. The SFHs were derived in a uniform manner from high-qu…
Discovery of the First Giant Double Radio Relic in a Galaxy Cluster Found in the Planck Sunyaev-Zel'dovich Cluster Survey: PLCK G287.0+32.9
Werner, Norbert; Ishwara-Chandra, C. H.; Joshi, Santosh +6 more
We report the discovery of large-scale diffuse non-thermal radio emission in PLCK G287.0+32.9, an exceptionally hot (T ~ 13 keV), massive, and luminous galaxy cluster, strongly detected by the Planck satellite in a recent, all-sky blind search for new clusters through Sunyaev-Zel'dovich effect. Giant Metrewave Radio Telescope 150 MHz and Very Larg…