Search Publications
A Pair of Leading Spiral Arms in a Luminous Infrared Galaxy?
Mattila, Seppo; Väisänen, Petri; Ryder, Stuart +1 more
Leading spiral arms are a rare phenomenon. We present here one of the very few convincing candidates of spiral arms opening counterintuitively in the same direction as the galaxy disk is rotating. This detection in the luminous IR galaxy (LIRG) IRAS 18293-3413 is based on near-infrared (NIR) adaptive optics imaging with the Very Large Telescope an…
The Plasma Structure of the Southwestern Region of the Cygnus Loop with the XMM-Newton Observatory
Katsuda, Satoru; Uchida, Hiroyuki; Tsunemi, Hiroshi +1 more
We observed the southwestern region of the Cygnus Loop in two pointings with XMM-Newton. The region observed is called the "blow-out" region, which is extended further in the south. The origin of the "blow out" is not well understood, but it is suggested that there is another supernova remnant here in radio observation. To investigate in detail th…
Parallel Motions of Coronal Hard X-Ray Source and Hα Ribbons
Gary, Dale E.; Lee, Jeongwoo
During solar flares Hα ribbons form and often move away from the local magnetic polarity inversion line (PIL). While the motion perpendicular to the PIL has been taken as evidence for coronal magnetic reconnection in the so-called CSHKP standard model, the other velocity component parallel to the PIL is much less adopted as a property of the magne…
Photochemical Enrichment of Deuterium in Titan's Atmosphere: New Insights from Cassini-Huygens
Mousis, Olivier; Lunine, Jonathan I.; Vuitton, Véronique +2 more
Cassini-Huygens data are used to reexamine the potential sources of the D/H enhancement over solar, measured in methane, in Titan's atmosphere. Assuming that the system is closed with respect to carbon, the use of constraints from the Huygens probe for the determination of the current mass of atmospheric methane and the most up-to-date determinati…
Radio Continuum Jet in NGC 7479
Laine, Seppo; Beck, Rainer
The barred galaxy NGC 7479 hosts a remarkable jetlike radio continuum feature: bright, 12 kpc long in projection, and hosting an aligned magnetic field. The degree of polarization is 6%-8% along the jet and remarkably constant, which is consistent with helical field models. The radio brightness of the jet suggests strong interaction with the ISM a…
X-Ray Sources in the Star-Forming Galaxies NGC 4194 and NGC 7541
Kaaret, Philip; Alonso-Herrero, Almudena
We examine the X-ray point-source population and 2-10 keV luminosity for two galaxies with high star formation rates (SFRs), NGC 4194 and NGC 7541. The X-ray point-source luminosity function (XLF) for these two galaxies is consistent with the XLF found by Grimm et al. for a sample of star-forming galaxies. Combining our results with a sample of ga…
LBT Discovery of a Yellow Supergiant Eclipsing Binary in the Dwarf Galaxy Holmberg IX
Burwitz, V.; Garnavich, P. M.; Kochanek, C. S. +14 more
In a variability survey of M81 using the Large Binocular Telescope we have discovered a peculiar eclipsing binary (MV ~ - 7.1) in the field of the dwarf galaxy Holmberg IX. It has a period of 271 days, and the light curve is well fit by an overcontact model in which both stars are overflowing their Roche lobes. It is composed of two yel…
Comparisons between Isothermal and NFW Mass Profiles for Strong-Lensing Galaxy Clusters
Huang, J. -S.; Mellier, Yannick; Bartelmann, Matthias +3 more
While both isothermal and NFW-based mass models for galaxy clusters are widely adopted in strong-lensing studies, they cannot easily be distinguished based solely on observed positions of arcs and arclets. We compare the magnifications predicted for giant arcs obtained from isothermal and NFW profiles, taking axially symmetric and asymmetric mass …
Probing the Central Regions of Nearby Compact Elliptical Galaxies
Davidge, T. J.; Beck, Tracy L.; McGregor, Peter J.
K-band spectroscopic observations recorded with NIFS+ALTAIR on Gemini North are used to probe the central arcsecond of the compact elliptical galaxies NGC 4486B, NGC 5846A, and M32. The angular resolution of these data is ~0.1'' FWHM; this corresponds to a spatial scale of 12 pc in NGC 5846A, which is the most distant galaxy in the samp…
A Cryogenic Liquid-Mirror Telescope on the Moon to Study the Early Universe
Eisenstein, Daniel J.; Sivanandam, Suresh; Foing, Bernard +9 more
We have studied the feasibility and scientific potential of zenith observing liquid-mirror telescopes having 20-100 m diameters located on the Moon. They would carry out deep infrared surveys to study the distant universe and follow up discoveries made with the 6 m James Webb Space Telescope (JWST), with more detailed images and spectroscopic stud…