Search Publications
Galaxy colours in the AKARI deep SEP survey
Nakagawa, Takao; Shirahata, Mai; Jeong, Woong-Seob +7 more
We investigate the segregation of the extragalactic population via colour criteria to produce an efficient and inexpensive methodology to select specific source populations as a function of far-infrared flux. Combining galaxy evolution scenarios and a detailed spectral library of galaxies, we produce simulated catalogues incorporating segregation …
INTEGRAL observations of the Small Magellanic Cloud
Udalski, A.; Hill, A. B.; Coe, M. J. +10 more
The first INTEGRAL observations of the Small Magellanic Cloud (SMC) (carried out in 2003) are reported in which two sources are clearly detected. The first source, SMC X-1, shows a hard X-ray eclipse and measurements of its pulse period indicate a continuation of the long-term spin-up now covering approximately 30 years. The second source is likel…
Proton irradiation of swept-charge devices for the Chandrayaan-1 X-ray Spectrometer (C1XS)
Smith, D. R.; Gow, J.; Holland, A. D.
This paper presents work carried out in support of swept-charge device (SCD) characterisation for the Chandrayaan-1 X-ray Spectrometer (C1XS) instrument. A brief overview of the C1XS instrument is presented, followed by a description of SCD structure and operation. The SCD test facility and method of device characterisation using two different dri…
The 2-µm spectroscopy of Huygens probe landing site on Titan with Very Large Telescope/Nasmyth Adaptive Optics System Near-Infrared Imager and Spectrograph
Drossart, P.; Gendron, E.; Rannou, P. +5 more
Several ground-based telescopes followed the event of the Huygens probe descent through Titan's atmosphere (14 January 2005). We used the Nasmyth Adaptive Optics System Near-Infrared Imager and Spectrograph (NACO) adaptive optics system at the UT-4 of the Very Large Telescope in Chile to perform both spectroscopic and imaging measurements of Titan…
Discovery of a Transient X-Ray Source in the Compact Stellar Nucleus of NGC 2403
Soria, Roberto; Tennant, Allyn F.; Swartz, Douglas A. +1 more
We report the discovery of an X-ray source coincident with the nuclear star cluster at the dynamical center of the nearby late-type spiral galaxy NGC 2403. The X-ray luminosity of this source varies from below detection levels, ~1035 erg s-1 in the 0.5-8.0 keV band to 7×1038 erg s-1 on timescales between…
XMM-Newton view of the double-peaked Fe Kα complex in E1821+643
Guainazzi, M.; Santos-Lleó, M.; Jiménez-Bailón, E. +3 more
We present the results of the analysis of the hard band XMM-Newton spectra of the luminous, L2{-10 keV}∼3.4×1045 erg/s, radio-quiet quasar, E 1821+643. Two emission features were observed in the 6-7 keV rest frame band, confirming previous Chandra detection of these structures. We interpret these features as two single emissi…
Small-Scale Systems of Galaxies. III. X-Ray-detected Elliptical+Spiral Galaxy Pairs in Low-Density Environments
Held, E. V.; Rizzi, L.; Trinchieri, G. +4 more
We present a comprehensive study of the local environments of four elliptical+spiral (E+S) galaxy pairs with the main goal of investigating their formation/evolution histories. We obtained new XMM-Newton data for two pairs (RR 143 and RR 242) that complement existing ROSAT data for the other two (RR 210 and RR 216). The new observations reveal dif…
Emission-Line Gas Kinematics in the Vicinity of the Supermassive Black Holes in Nearby Radio Galaxies
Baum, Stefi A.; O'Dea, Christopher P.; Noel-Storr, Jacob
We describe our characterization of the kinematics of the emission-line gas in the nuclear regions of a complete sample of 21 nearby radio galaxies. We obtained data using the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope. We show that the point-to-point variations are largest perpendicular to the disks and in nuclei whe…
Redshift-distance relations from type Ia supernova observations. New constraints on grey dust models
Cepa, J.; Robaina, A. R.
Extinction due to intergalactic grey dust has been proposed as an alternative to accelerated expansion to account for the dimming of SnIa fluxes beyond z ≃ 0.5. The "replenishing" grey dust model, although fitting the observational data, does not seem to be based on physical assumptions. For this reason, in this paper we propose a new grey dust mo…
Planetary science: Inside Enceladus
Spencer, John; Grinspoon, David
Chemical analysis of a plume emanating from near the south pole of Enceladus indicates that the interior of this saturnian moon is hot. Could it have been hot enough for complex organic molecules to be made?