Search Publications
AKARI Observations of Circumstellar Dust in the Globular Clusters NGC 104 and NGC 362
Ohyama, Y.; Matsunaga, N.; Takagi, T. +19 more
We report on preliminary results of AKARI observations of two globular clusters, NGC 104 and NGC 362. Imaging data covering areas of about 10 F_{7} ratio being greater than unity in NGC 362. Six out of the eight have no 2MASS counterparts. However, we found no such source in NGC 104.
Intensity variations inside supergranules
Roudier, Th.; Meunier, N.; Tkaczuk, R.
Context: The convective origin of supergranulation is highly controversial. Past measurements of intensity variations inside supergranules have often been influenced by the brightness enhancement at the cell boundaries due to the magnetic network.
Aims: We conduct a precise determination of intensity variations inside supergranules.
Method…
Monitoring the Variable Interstellar Absorption toward HD 219188 with Hubble Space Telescope STIS
Welty, Daniel E.
We discuss the results of continued optical and UV spectroscopic monitoring of the variable intermediate-velocity (IV) absorption at vsolar=-38 km s-1 toward HD 219188. After reaching maxima in mid-2000, the column densities of both Na I and Ca II in that IV component declined by factors >~2 by the end of 2006. Comparisons…
Star Formation, Radio Sources, Cooling X-Ray Gas, and Galaxy Interactions in the Brightest Cluster Galaxy in 2A0335+096
O'Dea, Christopher P.; Donahue, Megan; Voit, G. Mark +2 more
We present deep emission-line imaging taken with the new SOAR Optical Imager of the brightest cluster galaxy (BCG) in the nearby (z=0.035) X-ray cluster of galaxies 2A0335+096. We also present our analysis of additional, multiwavelength observations for the BCG, including long-slit optical spectroscopy, archival VLA radio data, Chandra X-ray imagi…
J- and Ks-Band Galaxy Counts and Color Distributions in the AKARI North Ecliptic Pole Field
Oyabu, Shinki; Matsuhara, Hideo; Takagi, Toshinobu +5 more
We present the J- and Ks-band galaxy counts and galaxy colors covering 750 arcmin2 in the deep AKARI north ecliptic pole (NEP) field, using the Florida Multi-object Imaging Near-IR Grism Observational Spectrometer on the Kitt Peak National Observatory 2.1 m telescope. The limiting magnitudes with a signal-to-noise ratio of 3 …
Probing the Nature of the G1 Clump Stellar Overdensity in the Outskirts of M31
Lewis, Geraint F.; Ibata, Rodrigo A.; Johnston, Kathryn V. +5 more
We present deep Hubble Space Telescope ACS observations of the G1 clump, a distinct stellar overdensity lying at ~30 kpc along the southwestern major axis of M31, close to the G1 globular cluster (from the work of Ferguson and coworkers). Our well-populated color-magnitude diagram reaches ~7 mag below the red giant branch tip with 90% completeness…
HD 97048's Circumstellar Environment as Revealed by a Hubble Space Telescope ACS Coronagraphic Study of Disk Candidate Stars
Kamp, I.; Meixner, M.; Ardila, D. R. +5 more
We present the results of a coronagraphic scattered-light imaging survey of six young disk candidate stars using the Hubble Space Telescope Advanced Camera for Surveys. The observations made use of the 1.8" occulting spot through the F606W (broad V) filter. Circumstellar material was imaged around HD 97048, a Herbig Ae/Be star located in the Chama…
The Field of the TeV Source HESS J1804-216 in X-Rays and Other Wavelengths
Garmire, G. P.; Pavlov, G. G.; Kargaltsev, O.
The field of the extended TeV source HESS J1804-216 was serendipitously observed with the Chandra ACIS detector on 2005 May 4. The data reveal several X-ray sources within the bright part of HESS J1804-216. The brightest of these objects, CXOU J180432.4-214009, which has been also detected with Swift (2005 November 3) and Suzaku (2006 April 6), is…
Craters, smooth terrains, flows, and layering on the comet nuclei
Keller, H. U.; Basilevsky, A. T.
The paper considers morphology of craters, smooth surfaces, and flows as well as signatures of layering observed on nuclei of Borrelly, Wild 2, and Tempel 1. In our analysis, we emphasize the role of the so-called planation process, which involves avalanche-type flows and can be responsible for the formation of flow-like features, smooth terrains,…
Structure through colour: a pixel approach towards understanding galaxies
Conselice, C. J.; Lanyon-Foster, M. M.; Merrifield, M. R.
We present a study of pixel colour-magnitude diagrams (pCMDs) for a sample of 69 nearby galaxies chosen to span a wide range of Hubble types. Our goal is to determine how useful a pixel approach is for studying galaxies according to their stellar light distributions and content. The galaxy images were analysed on a pixel-by-pixel basis to reveal t…