402 citations · 5k across the 120 of their papers we have counts for
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A new activity phase of the blazar 3C 454.3. Multifrequency observations by the WEBT and XMM-Newton in 2007-2008
C. M. Raiteri, M. Villata, V. M. Larionov +2
We present and analyse the WEBT multifrequency observations of 3C 454.3 in the 2007-2008 observing season, including XMM-Newton observations and near-IR spectroscopic monitoring, a…
Photometric/spectroscopic analyses and magnetic activity in young late-type stars
K. Biazzo, A. Frasca, E. Marilli +3
We present the work in progress of a study based on photometric and spectroscopic observations of young Weak-line T Tauri and Post T Tauri stars just attiving on the Zero Age Main…
New triple systems in the RasTyc sample of stellar X-ray sources
A. Klutsch, A. Frasca, P. Guillout +4
During the study of a large set of late-type stellar X-ray sources, we discovered a large fraction of multiple systems. In this paper we investigate the orbital elements and kinema…
Magnetic activity in the young star SAO 51891
K. Biazzo, A. Frasca, E. Marilli +3
We present preliminary results on a study based on contemporaneous photometric and spectroscopic observations of the young K0-1V star SAO 51891. We find that SAO 51891, a possible…
The star formation in the L1615/L1616 cometary cloud
Davide Gandolfi, Juan M. Alcalá, Silvio Leccia +6
The present work aims at performing a comprehensive census and characterisation of the pre-main sequence (PMS) population in the cometary cloud L1615/L1616, in order to assess the…
The young population of the Chamaeleon II dark cloud
Loredana Spezzi, Juan M. Alcala', Elvira Covino +9
We discuss the results of the optical spectroscopic follow-up of pre-main sequence (PMS) objects and candidates selected in the Chamaeleon II dark cloud based on data from the Spit…
Multifrequency monitoring of the blazar 0716+714 during the GASP-WEBT-AGILE campaign of 2007
M. Villata, C. M. Raiteri, V. M. Larionov +5
Since the CGRO operation in 1991-2000, one of the primary unresolved questions about the blazar gamma-ray emission has been its possible correlation with the low-energy (in particu…
Chromospheric features of LQ Hydrae from H-alpha line profiles
A. Frasca, Zs. Kovari, K. G. Strassmeier +1
We analyze the H-alpha spectral variability of the rapidly-rotating K1-dwarf LQ Hya using high-resolution H-alpha spectra recorded during April-May 2000. Chromospheric parameters w…
Spots, plages, and flares on lambda Andromedae and II Pegasi
A. Frasca, K. Biazzo, G. Tas +2
We present the results of a contemporaneous photometric and spectroscopic monitoring of lambda And and II Peg aimed at investigating the behavior of surface inhomogeneities in the…
A Spectroscopic Study of the Algol-type Binaries S Equulei and KO Aquilae: Absolute Parameters and Mass Transfer
F. Soydugan, A. Frasca, E. Soydugan +3
We present and analyze high-resolution optical spectra of the Algol binaries S Equ and KO Aql. New accurate radial velocities for the hotter primary components are obtained. Thanks…
Effective temperature vs line-depth ratio for ELODIE spectra. Gravity and rotational velocity effects
K. Biazzo, A. Frasca, S. Catalano +1
The dependence on the temperature of photospheric line-depth ratios (LDRs) in the spectral range 6190-6280 A is investigated by using a sample of 174 ELODIE Archive stellar spectra…
A WFI survey in the Chamaeleon II dark cloud
L. Spezzi, J. M. Alcalá, A. Frasca +2
We present the results of an optical multi-band survey for low-mass Pre-Main Sequence (PMS) stars and young Brown Dwarfs (BDs) in the Chamaeleon II (Cha II) dark cloud. This survey…
Abundant crystalline silicates in the disk of a very low mass star
B. Merin, J. -C. Augereau, E. F. van Dishoeck +16
We announce the discovery of SST-Lup3-1, a very low mass star close to the brown dwarf boundary in Lupus III with a circum(sub)stellar disk, discovered by the `Cores to Disks' Spit…
Newly discovered active binaries in the RasTyc sample of stellar X-ray sources
A. Frasca, P. Guillout, E. Marilli +2
We present preliminary results of follow-up optical observations, both photometric and spectroscopic, of stellar X-ray sources, selected from the cross-correlation of ROSAT All-Sky…
Photometric and spectroscopic follow-up of optical counterparts of X-ray sources in the RasTyc sample
Antonio Frasca, Patrick Guillout, Rubens Freire-Ferrero +2
The cross-correlation between the ROSAT all-sky survey (~150000 sources) and the Tycho mission (~1000000 stars) catalogs has selected about 14000 stellar X-ray sources (RasTyc samp…
A multisite photometric campaign on the Pre-Main-Sequence delta Scuti pulsator IP Per
V. Ripepi, S. Bernabei, M. Marconi +18
We present the results of a photometric multisite campaign on the Scuti Pre-Main-Sequence star IP Per. Nine telescopes have been involved in the observations, with a total of a…
Coordinated Multiwavelength Observations of BL Lacertae in 2000
M. Boettcher
BL Lacertae was the target of an extensive multiwavelength monitoring campaign in the second half of 2000. Simultaneous or quasi-simultaneous observations were taken at radio (UMRA…