Search Publications
XMM-Newton Observation of the Northwest Radio Relic Region in A3667
Sarazin, Craig L.; Nakazawa, Kazuhiro; Wik, Daniel R. +2 more
A3667 is the archetype of a merging cluster with radio relics. The northwest (NW) radio relic is the brightest cluster relic or halo known and is believed to be due to a strong merger shock. We have observed the NW relic for ~40 ks of net XMM-Newton time. We observe a global decline of temperature across the relic from 6 to 1 keV, similar to the S…
Reconstructing Coronal Mass Ejections with Coordinated Imaging and in Situ Observations: Global Structure, Kinematics, and Implications for Space Weather Forecasting
Vourlidas, Angelos; Thernisien, Arnaud; Bale, Stuart D. +4 more
We reconstruct the global structure and kinematics of coronal mass ejections (CMEs) using coordinated imaging and in situ observations from multiple vantage points. A forward modeling technique, which assumes a rope-like morphology for CMEs, is used to determine the global structure (including orientation and propagation direction) from coronagrap…
The Nature of Starbursts. II. The Duration of Starbursts in Dwarf Galaxies
McQuinn, Kristen B. W.; Cannon, John M.; Skillman, Evan D. +7 more
The starburst phenomenon can shape the evolution of the host galaxy and the surrounding intergalactic medium. The extent of the evolutionary impact is partly determined by the duration of the starburst, which has a direct correlation with both the amount of stellar feedback and the development of galactic winds, particularly for smaller mass dwarf…
On Sizes, Kinematics, M/L Gradients, and Light Profiles of Massive Compact Galaxies at z ~ 2
van Dokkum, Pieter G.; Franx, Marijn; Hernquist, Lars +5 more
We present a detailed analysis of the structure and resolved stellar populations of simulated merger remnants, and compare them to observations of compact quiescent galaxies at z ~ 2. We find that major merging is a viable mechanism to produce systems of ~1011 M sun and ~1 kpc size, provided the gas fraction at the time of fi…
Feeding versus feedback in NGC4151 probed with Gemini NIFS - II. Kinematics
Martini, P.; Storchi-Bergmann, T.; Riffel, Rogemar A. +3 more
We have used the Gemini Near-infrared Integral Field Spectrograph (NIFS) to map the gas kinematics of the inner ~200 × 500pc2 of the Seyfert galaxy NGC4151 in the Z, J, H and K bands at a resolving power of >=5000 and spatial resolution of ~8pc. The ionized gas emission is most extended along the known ionization bi-cone at position …
A Multiwavelength Study of a Sample of 70 µm Selected Galaxies in the COSMOS Field. II. The Role of Mergers in Galaxy Evolution
Aussel, H.; Le Floc'h, E.; Kartaltepe, Jeyhan S. +26 more
We analyze the morphological properties of a large sample of 1503 70 µm selected galaxies in the COSMOS field spanning the redshift range 0.01 < z < 3.5 with a median redshift of 0.5 and an infrared luminosity range of 108 < L IR(8 - 1000 µm)< 1014 L sun with a median luminosity o…
The Herschel Space Observatory view of dust in M81
Elbaz, D.; Bock, J. J.; Clements, D. L. +57 more
We use Herschel Space Observatory data to place observational constraints on the peak and Rayleigh-Jeans slope of dust emission observed at 70-500 µm in the nearby spiral galaxy M81. We find that the ratios of wave bands between 160 and 500 µm are primarily dependent on radius but that the ratio of 70 to 160 µm emission shows no …
On the fraction of star clusters surviving the embedded phase
Bastian, N.; Kennicutt, R. C.; Goddard, Q. E.
In this paper we derive ages and masses for 276 clusters in the merger galaxy NGC 3256. This was achieved by taking accurate photometry in four wavebands from archival Hubble Space Telescope images. Photometric measurements are compared to synthetic stellar population (SSP) models to find the most probable age, mass and extinction. The cluster pop…
LoCuSS: A Comparison of Cluster Mass Measurements from XMM-Newton and Subaru—Testing Deviation from Hydrostatic Equilibrium and Non-thermal Pressure Support
Smith, Graham P.; Babul, Arif; Marrone, Daniel P. +8 more
We compare X-ray hydrostatic and weak-lensing mass estimates for a sample of 12 clusters that have been observed with both XMM-Newton and Subaru. At an over-density of Δ = 500, we obtain 1 - M X/M WL = 0.01 ± 0.07 for the whole sample. We also divided the sample into undisturbed and disturbed sub-samples based on quantitative…
Driving Mechanism and Onset Condition of a Confined Eruption
Ding, M. D.; Schmieder, B.; Li, H. +3 more
We study a confined eruption accompanied by an M1.1 flare in solar active region (AR) NOAA 10767 on 2005 May 27, where a pre-eruptive magnetic flux rope was reported in a nonlinear force-free field (NLFFF) extrapolation. The observations show a strong writhing motion of the erupting structure, suggesting that a flux rope was indeed present and con…