Search Publications
The HeII Fowler lines and the OIII and NIII Bowen fluorescence lines in the symbiotic nova RR Telescopii
Danziger, J.; Bonifacio, P.; Selvelli, P.
Aims:A detailed study of the O III and N III Bowen lines in the spectrum of RR Tel.
Methods: Absolute intensities for the He II, O III, and N III emission lines have been obtained from STIS, UVES, FEROS and IUE data, after re-calibration of UVES and FEROS on the STIS scale.
Results: A new measure of reddening (E(B-V) 0.00) has b…
GQ Lup B Visible and Near-Infrared Photometric Analysis
Macintosh, Bruce; Barman, Travis; Marois, Christian
We have reanalyzed archival HST and Subaru data of the recently discovered planetary mass companion (PMC) GQ Lup B. With these we produce the first R- and I-band photometry of the companion and fit a radius and effective temperature using detailed model atmospheres. We find an effective temperature of 2335+/-100 K, a radius of 0.38+/-0.05 Rso…
On the origin of perennial water ice at the south pole of Mars: A precession-controlled mechanism?
Bibring, J. -P.; Langevin, Y.; Clancy, R. T. +3 more
The poles of Mars are known to have recorded recent (<107 years) climatic changes. While the south polar region appears to have preserved its million-year-old environment from major resurfacing events, except for the small portion containing the CO2 residual cap, the discovery of residual water ice units in areas adjacent …
Photospheric magnetic evolution of super active regions
Romano, P.; Zuccarello, F.
Context: Solar flares are one of the most interesting phenomena of solar activity. Although many authors agree that their energy release is related to magnetic reconnection, the phases preceding the magnetic reconnection process are still unclear in several respects.
Aims: We studied the magnetic flux evolution in 26 super active regions obser…
The Merger in Abell 576: A Line-of-Sight Bullet Cluster?
Bregman, Joel N.; Dupke, Renato A.; Mirabal, Nestor +1 more
Using a combination of Chandra and XMM-Newton observations, we confirmed the presence of a significant velocity gradient along the northeast-southwest direction in the intracluster gas of the cluster Abell 576. The results are consistent with a previous ASCA SIS analysis of this cluster. The error-weighted average over the ACIS-S3 and EPIC MOS1 an…
Initial Observations of Sunspot Oscillations Excited by Solar Flare
Kosovichev, A. G.; Sekii, T.
Observations of a large solar flare on 2006 December 13 using Solar Optical Telescope (SOT) on board the Hinode spacecraft revealed high-frequency oscillations excited by the flare in the sunspot chromosphere. These oscillations are observed in the region of strong magnetic field of the sunspot umbra and may provide a new diagnostic tool for probi…
A study of the Sunyaev-Zel'dovich increment using archival SCUBA data
Halpern, Mark; Scott, Douglas; Zemcov, Michael +2 more
In a search for evidence of the short wavelength increment in the Sunyaev-Zel'dovich (SZ) effect, we have analysed archival galaxy cluster data from the Submillimetre Common User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope, resulting in the most complete pointed survey of clusters at 850µm to date. SCUBA's 850-µm passb…
On the distance of PG 1553+11 . A lineless BL Lacertae object active in the TeV band
Falomo, R.; Uslenghi, M.; Treves, A.
Context: The redshift of
Aims: We intend to provide a lower limit for the distance of the object.
Methods: We used a χ2 procedure to constrain…
Fundamental parameters of He-weak and He-strong stars
Frémat, Y.; Zorec, J.; Arias, M. L. +3 more
Context: He-weak and He-strong stars are chemically peculiar AB objects whose He lines are anomalously weak or strong for their MK spectral type. The determination of fundamental parameters for these stars is often more complex than for normal stars due to their abundance anomalies.
Aims: We discuss the determination of fundamental parameters:…
Chorus source properties that produce time shifts and frequency range differences observed on different Cluster spacecraft
Gurnett, D. A.; Pickett, J. S.; SantolíK, O. +3 more
We present an explanation of frequency range differences and time shifts between corresponding chorus elements of whistler mode chorus which have been recently observed on multiple Cluster spacecraft. We show that a nonmoving or quasi-static source that emits waves in a relatively narrow interval of wave normal angles and that varies both the wave…