Search Publications
Molecular Gas Evolution Across a Spiral Arm in M51
Scoville, Nick; Koda, Jin; Egusa, Fumi
We present sensitive and high angular resolution CO(1-0) data obtained by the Combined Array for Research in Millimeter-wave Astronomy observations toward the nearby grand-design spiral galaxy M51. The angular resolution of 0farcs7 corresponds to 30 pc, which is similar to the typical size of giant molecular clouds (GMCs), and the sensitivity is a…
Energy budgets in collisionless magnetic reconnection: Ion heating and bulk acceleration
Belmont, G.; Aunai, N.; Smets, R.
This paper investigates the energy transfer in the process of collisionless antiparallel magnetic reconnection. Using two-dimensional hybrid simulations, we measure the increase of the bulk and thermal kinetic energies and compare it to the loss of magnetic energy through a contour surrounding the ion decoupling region. It is shown, for both symme…
X-ray softening in the new X-ray transient XTE J1719-291 during its 2008 outburst decay
Maccarone, T. J.; Degenaar, N.; Wijnands, R. +5 more
The X-ray transient XTE J1719-291 was discovered with Rossi X-ray Timing Explorer/Proportional Counter Array (RXTE/PCA) during its outburst in 2008 March, which lasted at least 46 d. Its 2-10 keV peak luminosity is 7 × 1035 erg s-1 assuming a distance of 8 kpc, which classifies the system as a very faint X-ray transient. The …
The Infrared Continuum Sizes of Be Star Disks
Gies, D. R.; Schaefer, G. H.; Touhami, Y.
We present an analysis of the near-infrared continuum emission from the circumstellar gas disks of Be stars using a radiative transfer code for a parameterized version of the viscous decretion disk model. This isothermal gas model creates predicted images that we use to estimate the half-width at half-maximum emission radius along the major axis o…
The Solar Neighborhood. XXIII. CCD Photometric Distance Estimates of SCR Targets—77 M Dwarf Systems within 25 pc
Henry, Todd J.; Winters, Jennifer G.; Jao, Wei-Chun +3 more
We present CCD photometric distance estimates of 100 SCR (SuperCOSMOS RECONS) systems with µ >= 0farcs18 yr-1, 29 of which are new discoveries previously unpublished in this series of papers. These distances are estimated using a combination of new VRI photometry acquired at CTIO and JHK magnitudes extracted from 2MASS. The est…
The Stability of Low Surface Brightness Disks Based on Multi-wavelength Modeling
Gallagher, J. S.; Wood, K.; Matthews, L. D. +1 more
To investigate the structure and composition of the dusty interstellar medium (ISM) of low surface brightness (LSB) disk galaxies, we have used multi-wavelength photometry to construct spectral energy distributions for three low-mass, edge-on LSB galaxies (V rot = 88-105 km s-1). We use Monte Carlo radiation transfer codes th…
Azimuthal variations of magnetic field strength and inclination on penumbral boundaries
Jurčák, J.
Aims: I try to determine the properties of the magnetic field on the inner and outer penumbral boundaries and find out if either magnetic field strength or inclination are constant there and if these plasma parameters depend on the sunspot area.
Methods: The spectropolarimetric data obtained with the Hinode satellite were analysed. Activ…
Dust and Chemical Abundances of the Sagittarius Dwarf Galaxy Planetary Nebula Hen2-436
Izumiura, Hideyuki; Meixner, Margaret; Otsuka, Masaaki +3 more
We have estimated elemental abundances of the planetary nebula (PN) Hen2-436 in the Sagittarius (Sgr) spheroidal dwarf galaxy using ESO/VLT FORS2, Magellan/MMIRS, and Spitzer/IRS spectra. We have detected candidates of fluorine [F II] λ4790, krypton [Kr III] λ6826, and phosphorus [P II] λ7875 lines and successfully estimated the abundances of thes…
Obscured Starburst Activity in High-redshift Clusters and Groups
Kocevski, Dale D.; McGrath, Elizabeth J.; Fassnacht, Christopher D. +6 more
Using Spitzer-Multiband Imaging Photometer 24 µm imaging and extensive Keck spectroscopy, we examine the nature of the obscured star-forming population in three clusters and three groups at z ~ 0.9. These six systems are the primary components of the Cl1604 supercluster, the largest structure imaged by Spitzer at redshifts approaching unity.…
Interior layered deposits within a perched basin, southern Coprates Chasma, Mars: Evidence for their formation, alteration, and erosion
Hauber, E.; Le Deit, L.; Gwinner, K. +3 more
A basin-like area containing three interior layer deposits (ILDs) on the southern margin of Coprates Chasma was studied. We interpret the area as an ancestral basin and demonstrate that ILD deposition postdates the formation of the current wall rock slopes. The geometry of the ILD and the wall rock spurs form a catchment area between each ILD and …