Search Publications
Modelling the carbon AGB star R Sculptoris. Constraining the dust properties in the detached shell based on far-infrared and sub-millimeter observations
Mecina, M.; Kerschbaum, F.; Maercker, M. +2 more
Context. On the asymptotic giant branch (AGB), Sun-like stars lose a large portion of their mass in an intensive wind and enrich the surrounding interstellar medium with nuclear processed stellar material in the form of molecular gas and dust. For a number of carbon-rich AGB stars, thin detached shells of gas and dust have been observed. These she…
Multiepoch, multiwavelength study of accretion onto T Tauri. X-ray versus optical and UV accretion tracers
Schmitt, J. H. M. M.; Güdel, M.; Robrade, J. +2 more
Classical T Tauri stars (CTTSs) accrete matter from the inner edge of their surrounding circumstellar disks. The impact of the accretion material on the stellar atmosphere results in a strong shock, which causes emission from the X-ray to the near-infrared (NIR) domain. Shock velocities of several 100 km s-1 imply that the immediate pos…
Search for sulfates on the surface of Ceres
McFadden, L. A.; Ruesch, O.; Li, J. -Y. +3 more
The formation of hydrated salts is an expected consequence of aqueous alteration of Main Belt objects, particularly for large, volatile-rich protoplanets like Ceres. Sulfates, present on water-bearing planetary bodies (e.g., Earth, Mars, and carbonaceous chondrite parent bodies) across the inner solar system, may contribute to Ceres' UV and IR spe…
Planetary nebulae with UVIT. II. Revelations from far-UV vision of Butterfly nebula NGC 6302
Sutaria, F.; Murthy, J.; Ray, A. +4 more
The high excitation planetary nebula, NGC 6302, has been imaged in two far-ultraviolet (FUV) filters, F169M (Sapphire; λeff: 1608 Å) and F172M (Silica; λeff: 1717 Å) and two near-UV (NUV) filters, N219M (B15; λeff: 2196 Å) and N279N (N2; λeff: 2792 Å) with the Ultra Violet Imaging Telescope (UVIT). The F…
The Identification of Hydrogen-deficient Cataclysmic Variable Donor Stars
Harrison, Thomas E.
We have used ATLAS12 to generate hydrogen-deficient stellar atmospheres to allow us to construct synthetic spectra to explore the possibility that the donor stars in some cataclysmic variables (CVs) are hydrogen deficient. We find that four systems, AE Aqr, DX And, EY Cyg, and QZ Ser, have significant hydrogen deficits. We confirm that carbon and …
The Gaia/IPHAS and Gaia/KIS value-added catalogues
Maccarone, T. J.; Knigge, C.; Pala, A. F. +7 more
We present a sub-arcsecond crossmatch of Gaia DR2 against the INT Photometric H α Survey of the Northern Galactic Plane Data Release 2 (IPHAS DR2) and the Kepler-INT Survey (KIS). The resulting value-added catalogues (VACs) provide additional precise photometry to the Gaia photometry (r, i, and H α for IPHAS, with additional U and g for KIS). In b…
Deep Chandra Observations of X-Ray Point Sources in M87
Goulding, Andy D.; Andrade-Santos, Felipe; Jones, Christine +6 more
We present a study of X-ray source populations in M87, the cD galaxy of the Virgo cluster, using 12 archival Chandra observations with a total exposure of ∼680 ks spanning about a decade. A total of 346 point-like sources are detected down to a limiting 0.5-8 keV luminosity of 4 × 1037 erg s-1 and out to a galactocentric radi…
Automatic Coregistration and orthorectification (ACRO) and subsequent mosaicing of NASA high-resolution imagery over the Mars MC11 quadrangle, using HRSC as a baseline
Muller, Jan-Peter; Sidiropoulos, Panagiotis; Watson, Gillian +2 more
This work presents the coregistered, orthorectified and mosaiced high-resolution products of the MC11 quadrangle of Mars, which have been processed using novel, fully automatic, techniques. We discuss the development of a pipeline that achieves fully automatic and parameter independent geometric alignment of high-resolution planetary images, start…
Geometric calibration of Colour and Stereo Surface Imaging System of ESA's Trace Gas Orbiter
Cremonese, Gabriele; Thomas, Nicolas; Tulyakov, Stepan +5 more
There are many geometric calibration methods for "standard" cameras. These methods, however, cannot be used for the calibration of telescopes with large focal lengths and complex off-axis optics. Moreover, specialized calibration methods for the telescopes are scarce in literature. We describe the calibration method that we developed for the Colou…
Probing the 9.7 µm interstellar silicate extinction profile through the Spitzer/IRS spectroscopy of OB stars
Gao, Jian; Li, Aigen; Shao, Zhenzhen +3 more
The 9.7 {µ}m interstellar spectral feature, arising from the Si-O stretch of amorphous silicate dust, is the strongest extinction feature in the infrared (IR). In principle, the spectral profile of this feature could allow one to diagnose the mineralogical composition of interstellar silicate material. However, observationally, the 9.7 {&mic…