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Solar Magnetic Tracking. III. Apparent Unipolar Flux Emergence in High-resolution Observations
Lamb, D. A.; DeForest, C. E.; Hagenaar, H. J. +2 more
Understanding the behavior of weak magnetic fields near the detection limit of current instrumentation is important for determining the flux budget of the solar photosphere at small spatial scales. Using 0farcs3-resolution magnetograms from the Solar Optical Telescope's Narrowband Filter Imager (NFI) on the Hinode spacecraft, we confirm that the p…
Bright optical day-side emission from extrasolar planet CoRoT-2b
Snellen, I. A. G.; Burrows, A.; de Mooij, E. J. W.
We present our analysis of the red-channel CoRoT data of extrasolar planet CoRoT-2b. A deep secondary eclipse is detected at a level of 1.02 ± 0.20 × 10-4, which suggests that all of the planet-signal detected previously in white light by Alonso et al. (2009, A&A, 501, L23) originates from the red channel. CoRoT-2b is the coolest ex…
The Herschel Virgo Cluster Survey. IV. Resolved dust analysis of spiral galaxies
Bomans, D. J.; Bianchi, S.; Fritz, J. +27 more
We present a resolved dust analysis of three of the largest angular size spiral galaxies, NGC 4501 and NGC 4567/8, in the Herschel Virgo Cluster Survey (HeViCS) science demonstration field. Herschel has unprecedented spatial resolution at far-infrared wavelengths and with the PACS and SPIRE instruments samples both sides of the peak in the far inf…
The detached dust shells of AQ Andromedae, U Antliae, and TT Cygni
Blommaert, J. A. D. L.; Jean, C.; Regibo, S. +14 more
Detached circumstellar dust shells are detected around three carbon variables using Herschel-PACS. Two of them are already known on the basis of their thermal CO emission and two are visible as extensions in IRAS imaging data. By model fits to the new data sets, physical sizes, expansion timescales, dust temperatures, and more are deduced. A compa…
Estimating the masses of Saturn’s A and B rings from high-optical depth N-body simulations and stellar occultations
Colwell, Joshua E.; Sremčević, Miodrag; Robbins, Stuart J. +2 more
We have completed a series of local N-body simulations of Saturn's B and A rings in order to identify systematic differences in the degree of particle clumping into self-gravity wakes as a function of orbital distance from Saturn and dynamical optical depth (a function of surface density). These simulations revealed that the normal optical depth o…
Morphology, stratigraphy, and mineralogical composition of a layered formation covering the plateaus around Valles Marineris, Mars: Implications for its geological history
Le Mouélic, S.; Bibring, J. -P.; Jaumann, R. +5 more
An extensive layered formation covers the high plateaus around Valles Marineris. Mapping based on HiRISE, CTX and HRSC images reveals these layered deposits (LDs) crop out north of Tithonium Chasma, south of Ius Chasma, around West Candor Chasma, and southwest of Juventae Chasma and Ganges Chasma. The estimated area covered by LDs is ∼42,300 km
HIFI spectroscopy of low-level water transitions in M 82
Teyssier, D.; Harris, A. I.; van der Werf, P. P. +23 more
We present observations of the rotational ortho-water ground transition, the two lowest para-water transitions, and the ground transition of ionised ortho-water in the archetypal starburst galaxy M 82, performed with the HIFI instrument on the Herschel Space Observatory. These observations are the first detections of the para-H2O(1…
Negative ions in the Enceladus plume
Lewis, G. R.; Coates, A. J.; Jones, G. H. +6 more
During Cassini's Enceladus encounter on 12th March 2008, the Cassini Electron Spectrometer, part of the CAPS instrument, detected fluxes of negative ions in the plumes from Enceladus. It is thought that these ions include negatively charged water group cluster ions associated with the plume and forming part of the 'plume ionosphere'. In this paper…
Accurate fundamental parameters for A-, F- and G-type Supergiants in the solar neighbourhood
Lambert, David L.; Lyubimkov, Leonid S.; Rostopchin, Sergey I. +2 more
The following parameters are determined for 63 Galactic supergiants in the solar neighbourhood: effective temperature Teff; surface gravity logg iron abundance logɛ(Fe) microturbulent parameter Vt; mass M/Msolar age t and distance d. A significant improvement in the accuracy of the determination of logg, and all pa…
A Geometrical Height Scale for Sunspot Penumbrae
Martínez Pillet, V.; Ruiz Cobo, B.; Puschmann, K. G.
Inversions of spectropolarimetric observations of penumbral filaments deliver the stratification of different physical quantities in an optical depth scale. However, without establishing a geometrical height scale, their three-dimensional geometrical structure cannot be derived. This is crucial in understanding the correct spatial variation of phy…