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Cold and hot gas in the most HI deficient compact groups
Yun, Min S.; Verdes-Montenegro, Lourdes; Borthakur, Sanchayeeta +2 more
Dense groups of galaxies should be prime sites for galaxy interactions and mergers, and their evolution has been the subject of controversy for 25 years. In order to explain the HI deficiency found in compact groups of galaxies we previously proposed an evolutionary scenario in which the amount of HI decreases with the secular evolutionary state o…
Discovery of Extended Emission around the Pulsar B0355+54
Ögelman, H.; Tepedelenliǧlu, E.
PSR B0355+54 is one of the handful of pulsars that have been observed with both Chandra and XMM-Newton. The analysis of the archival data has revealed the pulsar and a ~30" compact nebula surrounding it. XMM-Newton also has detected a trail that extends ~6' and, similar to the compact nebula, is also counteraligned with the proper motion of the pu…
Combined astrometric catalogue EOC-3. An improved reference frame for long-term Earth rotation studies
Vondrák, J.; Štefka, V.
Context: In the past, we collected the astrometric observations of latitude/universal time variations made worldwide at 33 observatories. These observations, re-analyzed with the Hipparcos Catalogue, were then used to determine the Earth Orientation Parameters (EOP) at 5-day intervals, covering the interval 1899.7-1992.0. Later on, new astrometric…
AEGIS: Galaxy Spectral Energy Distributions from the X-Ray to Radio
Ivison, R. J.; Cooper, M. C.; Huang, J. -S. +15 more
The All-Wavelength Extended Groth Strip International Survey (AEGIS) team presents broadband spectral energy distributions (SEDs), from X-ray to radio wavelengths, for 71 galaxies spanning the redshift range 0.55-1.16 (<z>~0.7). Galaxies with secure redshifts are selected from a small (22 arcmin2) subsection of the Keck/DEIMOS Gal…
A Silver Anniversary Observation of the X-Ray-Luminous SN 1978K in NGC 1313
Schlegel, E. M.; Lenz, E.
We describe the results of a 2003 Chandra ACIS-I observation of SN 1978K. The spectrum shows little flux below 0.6 keV, in contrast to the 2002 Chandra ACIS-S observation, which showed flux to 0.4 keV. Fitting the ACIS-I spectrum alone leads to two solutions depending on the value of the column density. A joint fit using a dual thermal plasma mode…
The Spectroscopic and Astrometric Orbits of HR 672
Pourbaix, D.; Fekel, Francis C.; Williamson, Michael
From a very extensive set of radial velocities obtained at Fairborn Observatory we have computed a new spectroscopic orbit for HR 672. This binary has an orbital period of 93.290 days and an eccentricity of 0.5249. The greatly improved orbital elements have been incorporated into a new astrometric orbit, which has an inclination of 110°, from Hipp…
A sensor to perform in-situ thermal conductivity determination of cometary and asteroid material
Banaszkiewicz, M.; Seweryn, K.; Wawrzaszek, R.
Measurements of the physical properties of surface and subsurface layers of planetary bodies often provide important information about the structure of the medium and processes that occur there. Thermal properties of the subsurface material of cometary nuclei are crucial in determining the heat and gas transport. Similarly, asteroids' regolith is …
The surface brightness of the Galaxy at the solar neighbourhood
Gould, A.; Combes, F.; Melchior, A. -L.
We present a new determination of the surface brightness of our Galaxy at the Solar Neighbourhood as observed from outside the Galaxy. We rely on various existing optical and infra-red surveys to obtain a multiwavelength estimate. On the one hand, scattered light does not contribute significantly to the surface brightness. On the other hand, optic…
Evidence for Three Subpopulations of Globular Clusters in the Early-Type Poststarburst Shell Galaxy AM 0139-655
Schweizer, François; Goudfrooij, Paul; Puzia, Thomas +2 more
We present deep Hubble Space Telescope ACS images of the poststarburst shell galaxy AM 0139-655. We find evidence for the presence of three distinct globular cluster (GC) subpopulations associated with this galaxy: a centrally concentrated young population (~0.4 Gyr), an intermediate-age population (~1 Gyr), and an old, metal-poor population simil…
Correction of SOHO CELIAS/SEM EUV measurements saturated by extreme solar flare events
Tsurutani, B. T.; Judge, D. L.; Jones, A. R. +2 more
The solar irradiance in the Extreme Ultraviolet (EUV) spectral bands has been observed with a 15 s cadence by the SOHO Solar EUV Monitor (SEM) since 1995. During remarkably intense solar flares the SEM EUV measurements are saturated in the central (zero) order channel (0.1-50.0 nm) by the flare soft X-ray and EUV flux. The first order EUV channel …