Search Publications
The Stellar Populations of dE Galaxies in Nearby Groups
Da Costa, G. S.
In this contribution Gemini-North NIRI J,K-observations are used to investigate the upper-Asymptotic Giant Branch (AGB) intermediate-age population in the M81 Group dwarf elliptical (dE) F8D1. Hubble Space Telescope (HST) `snapshot' V,I-observations are also analysed to investigate the upper-AGB populations in two other M81 Group dEs, DDO 71 and k…
The Cassini-Huygens flyby of Jupiter
Lebreton, Jean-Pierre; Matson, Dennis L.; Spilker, Linda J. +2 more
The Cassini-Huygens spacecraft flew by Jupiter on December 30, 2000. The instruments aboard the spacecraft started making scientific observations three months earlier. Joint, collaborative observations were carried out with the teams of other spacecraft, notably Galileo, and with Earth-based observers. An operational overview of the flyby is prese…
Local kinematics of dwarfs from the Tycho-2 data
Rybka, S. P.
The stellar velocity field of about 70000 dwarfs within 2 kps from the Sun is investigated from the "Tycho-2" data and known MK spectral classification. The Ogorodnikov-Milne model of a three-dimensional differential velocity field is used. The generalized Oort constants and components of the solar motion with respect to various spectral groups ar…
XMM-Newton observations of the BL Lac MS 0205.7+3509: A dense, low-metallicity absorber
Hanlon, L.; McBreen, B.; Smith, N. +5 more
The high-frequency-peaked BL Lac, MS 0205.7+3509 was observed twice with XMM-Newton. Both X-ray spectra are synchrotron-dominated, with mean 0.2-10 keV fluxes of 2.80±0.01 and 3.34±0.02×10-12 erg cm-2 s-1. The X-ray spectra are well fit by a power-law with absorption above the Galactic value, however no absorption …
Comprehensive Analysis of RGU Photometry in the Direction to M5
Bilir, S.; Karaali, S.; Buser, R.
The RGU-photographic investigation of an intermediate latitude field in the direction to the Galactic centre is presented. 164 extra-galactic objects, identified by comparison of Minnesota and Basel charts, are excluded from the program. Also, a region with size 0.104 square-degrees, contaminated by cluster (M5) stars and affected by background li…
Extended search for correlation between solar mean magnetic field BiSON data and coronal mass ejections
Chaplin, William J.; Pintér, Balázs; Elsworth, Yvonne P. +5 more
The Birmingham Solar-Oscillations Network (BiSON) has acquired high-precision solar mean magnetic field (SMMF) data on a 40-s cadence for a decade. We present attempts to compare such data from recent years with the occurrence of coronal mass ejections (CMEs) as recorded by LASCO, using correlation techniques applied to measurements from different…
XMM-Newton observations of OY Car III: OM light curve modelling, X-ray timing and spectral studies
Ramsay, G.; Hakala, P.
We revisit the XMM-Newton observations of the dwarf nova OY Car taken in July 2000 which occured shortly after an outburst. Ramsay et al. (\cite{Ramsay2001a}) found a prominent energy dependent modulation at a period of 2240 s: this modulation was only seen for ∼1/3 of the observation duration. In our new analysis, we examine this time interval in…
UVIS/HDAC Lyman-α observations of the geocorona during Cassini’s Earth swingby compared to model predictions
Keller, H. U.; Werner, S.; Korth, A. +1 more
The Hydrogen Deuterium Absorption Cell (HDAC) is part of the Ultraviolet Imaging Spectrograph (UVIS) experiment aboard the Cassini spacecraft. During Cassini's Earth swingby on August 18, 1999, HDAC was used as a photometer to measure solar Lyman-α radiation scattered by the neutral hydrogen atoms of the geocorona. These data provide information a…
Identification of broad-band waves above the auroral acceleration region: Cluster observations
Balogh, A.; André, M.; Buchert, S. +3 more
We investigate broad-band emissions at frequencies above the ion gyrofrequency on auroral field lines at geocentric distances of about 4.5 Earth radii. Observations by the Cluster satellites are used to study the wave characteristics and to determine the wave modes involved. All events include some bursts of broad-band emissions with a substantial…
The Nature of Near-Ultraviolet-selected Objects in the Chandra Deep Field-South
Gardner, Jonathan P.; Koekemoer, A. M.; Conselice, C. J. +3 more
We present the first results of the pure parallel near-UV observations with the Wide Field Planetary Camera 2 (WFPC2) in the Chandra Deep Field-South. The main goal is to search for the population of objects that contributes to the rise in the volume-averaged star formation rate at intermediate redshifts (z<1). A total of 34 objects were identi…