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Mid-infrared imaging and modelling of the dust shell around post-AGB star HD 187885 (IRAS 19500-1709)
Gledhill, T. M.; Clube, K. L.
We present 10- and 20-µm images of IRAS 19500-1709 taken with the mid-infrared camera, OSCIR, mounted on the Gemini North Telescope. An extended circumstellar envelope is detected, with the N-band image indicating an elongation in a north-east-south-west direction. We use a dust radiation transport code to fit the spectral energy distributio…
A New Way to Model the Solar Oscillation ℓ−ν Power Spectrum
Jefferies, Stuart M.; Vorontsov, Sergei V.
We present a new approach for the precise and accurate forward modeling of the solar oscillation ℓ−ν power spectrum. The approach is designed to provide the basis for a streamlined solar seismic inversion without measurements of the p-mode frequencies. The new strategy represents a paradigm change in how information is extracted from the oscillati…
The Nature of Close Companions of the BL Lacertae Objects 1ES 0502+675 and 1ES 1440+122
Falomo, R.; Treves, A.; Urry, C. M. +2 more
We report on deep radio images and optical spectroscopy of two BL Lac objects that have very close compact companions. The two targets, 1ES 0502+675 and 1ES 1440+122, were selected from the Hubble Space Telescope imaging survey of 110 BL Lacs as candidates for possible gravitational lensing. The new observations clearly demonstrate that the compan…
The composite starburst/AGN nature of the superwind galaxy NGC 4666
Palazzi, E.; Cappi, M.; Franceschini, A. +6 more
We report the discovery of a Compton-thick AGN and of intense star-formation activity in the nucleus and disk, respectively, of the nearly edge-on superwind galaxy NGC 4666. Spatially unresolved emission is detected by BeppoSAX only at energies <10 keV, whereas spatially resolved emission from the whole disk is detected by XMM-Newton. A promine…
Broadband X-ray Spectrum of the Intermediate Polar V2400 Oph
Sunyaev, R. A.; Lutovinov, A. A.; Revnivtsev, M. G. +2 more
We present the results of our analysis of the observations of the intermediate polar V2400 Oph by the INTEGRAL and RXTE observatories. We reconstructed the spectrum of the source over a wide (3-100 keV) energy range. The spectrum obtained can be fitted by a computed theoretical model of the post-shock emitting region with Tmax ~ 22 keV.…
Cluster observations of ULF waves with pulsating electron beams above the high latitude dusk-side auroral region
Winningham, J. D.; Balogh, A.; Dandouras, I. +8 more
We report observations by the four Cluster satellites of particle acceleration associated with ULF (Alfvén) waves at an altitude of 6RE above the dusk-side auroral region. All satellites observed upward accelerated ions and upgoing electron beams, which coincided with the upward field-aligned current around the plasmasheet boundary regi…
Jovian satellite positions from Hubble Space Telescope images
Mallama, Anthony; Aelion, Halley M.; Mallama, Celeste A.
An accurate technique has been developed for measuring planetocentric positions of Jupiter's satellites from Wide Field/Planetary Camera images. Our method of finding the centers of the satellites and planet is based upon established limb-fitting techniques, but we have adapted those techniques to astrometry. We compare our limb-fitting results wi…
Keck Adaptive Optics Imaging of 0.5 < z < 1 Field Galaxies from the Hubble Space Telescope Archive
Faber, S. M.; Koo, D. C.; Larkin, J. E. +6 more
We have employed natural guide star adaptive optics (AO) on the Keck II telescope to obtain near-infrared (H and K') images of three field galaxies, each of redshift greater than 0.5. These are among the highest-redshift non-active disk galaxies to be imaged with AO. Each of the galaxies was chosen because it had been observed previously with the …
Multi-object near-infrared Hα spectroscopy of z~ 1 star-forming galaxies in the Hubble Deep Field North
Wolf, Christian; Hippelein, Hans; Bunker, Andrew +6 more
We present preliminary results from a programme to obtain multi-object near-infrared spectroscopy of galaxies at redshifts 0.7 < z < 1.5. We are using the instrument CIRPASS (the Cambridge Infra-Red PAnoramic Survey Spectrograph), in multi-object mode, to survey Hα in galaxies at z~ 1. We aim to address the true star formation history of the…
New and Confirmed Triple Systems with Luminous Cool Primaries and Hot Companions
Parsons, Sidney B.
In the course of comparing parameters of evolved cool star plus hot main-sequence star binaries with theoretical isochrones, some discrepancies are found between implied stellar masses and the spectroscopic binary mass function or the measured angular separation. These are naturally explained if there is a third star in the system. Multiplicity is…