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The SLUGGS survey: globular cluster system kinematics and substructure in NGC 4365
Spitler, Lee R.; Forbes, Duncan A.; Romanowsky, Aaron J. +4 more
We present a kinematic analysis of the globular cluster (GC) system of the giant elliptical galaxy NGC 4365 and find several distinct kinematic substructures. This analysis is carried out using radial velocities for 269 GCs, obtained with the DEIMOS (DEep Imaging Multi-Object Spectrograph) instrument on the Keck II telescope as part of the SAGES L…
Why is IGR J17091-3624 So Faint? Constraints on Distance, Mass, and Spin from "Phase-resolved" Spectroscopy of the "Heartbeat" Oscillations
Rao, Anjali; Vadawale, S. V.
IGR J17091-3624 is a transient X-ray source and is believed to be a Galactic black hole candidate. Recently, it has received considerable attention due to the detection of peculiar variability patterns known as "heartbeats," which are quasi-periodic mini-outbursts repeated over timescales ranging between 5 and 70 s. So far, such variability patter…
Measurements of the Sun's High-latitude Meridional Circulation
Hathaway, David H.; Rightmire-Upton, Lisa; Kosak, Katie
The meridional circulation at high latitudes is crucial to the buildup and reversal of the Sun's polar magnetic fields. Here, we characterize the axisymmetric flows by applying a magnetic feature cross-correlation procedure to high-resolution magnetograms obtained by the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observator…
Titan's ionospheric composition and structure: Photochemical modeling of Cassini INMS data
Wahlund, J. -E.; Magee, B. A.; Mandt, K. E. +4 more
Titan's upper atmosphere produces an ionosphere at high altitudes from photoionization and electron impact that exhibits complex chemical processes in which hydrocarbons and nitrogen-containing molecules are produced through ion-molecule reactions. The structure and composition of Titan's ionosphere has been extensively investigated by the Ion and…
Using the Bullet Cluster as a Gravitational Telescope to Study z >~ 7 Lyman Break Galaxies
Stiavelli, Massimo; Treu, Tommaso; Bradač, Maruša +7 more
We use imaging obtained with the Hubble Space Telescope Wide Field Camera 3 to search for z 850 dropouts at z ~ 7 and J 110 dropouts at z ~ 9 lensed by the Bullet Cluster. In total we find 10 z 850 dropouts in our 8.27 arcmin2 field. Using magnification maps from a combined weak- and strong-lensing mass …
Internal Structure of Protocluster Galaxies: Accelerated Structural Evolution in Overdense Environments?
Zirm, Andrew W.; Toft, Sune; Tanaka, Masayuki
We present a high spatial resolution Hubble Space Telescope/NICMOS imaging survey in the field of a known protocluster surrounding the powerful radio galaxy MRC1138-262 at z = 2.16. Previously, we have shown that this field exhibits a substantial surface overdensity of red J-H galaxies. Here we focus on the stellar masses and galaxy effective radi…
X-Ray Emission from the Wolf-Rayet Bubble S 308
Gruendl, R. A.; Smith, R. C.; Chu, Y. -H. +4 more
The Wolf-Rayet (WR) bubble S 308 around the WR star HD 50896 is one of the only two WR bubbles known to possess X-ray emission. We present XMM-Newton observations of three fields of this WR bubble that, in conjunction with an existing observation of its northwest quadrant, map most of the nebula. The X-ray emission from S 308 displays a limb-brigh…
Stellar laboratories: new Ge V and Ge VI oscillator strengths and their validation in the hot white dwarf RE 0503-289
Rauch, T.; Werner, K.; Kruk, J. W. +2 more
Context. State-of-the-art spectral analysis of hot stars by means of non-LTE model-atmosphere techniques has arrived at a high level of sophistication. The analysis of high-resolution and high-S/N spectra, however, is strongly restricted by the lack of reliable atomic data for highly ionized species from intermediate-mass metals to trans-iron elem…
A Possible Ultra Strong and Broad Fe Kα Emission Line in Seyfert 2 Galaxy IRAS 00521-7054
Shu, X. W.; Wang, J. X.; Tan, Y. +1 more
We present XMM-Newton spectra of the Seyfert 2 Galaxy IRAS 00521-7054. A strong feature at ~6 keV (observer's frame) can be formally fitted with a strong (EW = 1.3 ± 0.3 keV in the rest frame) and broad Fe Kα line, extending down to 3 keV. The underlying X-ray continuum could be fitted with an absorbed power law (with Γ = 1.8 ± 0.2 and N H
On the Shapes and Structures of High-redshift Compact Galaxies
Glazebrook, Karl; Chevance, Mélanie; Abraham, Roberto G. +5 more
Recent deep Hubble Space Telescope WFC3 imaging suggests that a majority of compact quiescent massive galaxies at z ~ 2 may contain disks. To investigate this claim, we have compared the ellipticity distribution of 31 carefully selected high-redshift massive quiescent compact galaxies to a set of mass-selected ellipticity and Sérsic index distribu…