Search Publications
A double stellar generation in the globular cluster NGC 6656 (M 22). Two stellar groups with different iron and s-process element abundances
Milone, A. P.; Marino, A. F.; Bedin, L. R. +4 more
We present a chemical abundance analysis based on high resolution UVES spectra of seventeen bright giant stars in the Globular Cluster (GC) M 22. We obtained an average iron abundance of [Fe/H] = -1.76±0.02 (internal errors only) and an α enhancement of 0.36±0.04 (internal errors only). Na and O, and Al and O follow the well known anticorrelations…
PROSAC: a submillimeter array survey of low-mass protostars. II. The mass evolution of envelopes, disks, and stars from the Class 0 through I stages
Wilner, D. J.; van Dishoeck, E. F.; Lommen, D. +5 more
Context: The key question about early protostellar evolution is how matter is accreted from the large-scale molecular cloud, through the circumstellar disk onto the central star.
Aims: We constrain the masses of the envelopes, disks, and central stars of a sample of low-mass protostars and compare the results to theoretical models for the evol…
The great observatories origins deep survey. VLT/VIMOS spectroscopy in the GOODS-south field
Daddi, E.; Popesso, P.; Cesarsky, C. +10 more
Aims: We present the first results from the VIsible Multiobject Spectrograph (VIMOS) ESO/GOODS program of spectroscopy for faint galaxies in the Chandra Deep Field South (CDF-S). This program complements the FORS2 ESO/GOODS campaign.
Methods: All 3312 spectra were obtained in service mode with VIMOS at the ESO/VLT UT3. The VIMOS LR-Blue and MR…
CAIXA: a catalogue of AGN in the XMM-Newton archive. I. Spectral analysis
Bianchi, S.; Ponti, G.; Guainazzi, M. +2 more
Aims: We present CAIXA, a Catalogue of AGN In the XMM-Newton Archive. It consists of all the radio-quiet X-ray unobscured (N_H<2×1022 cm-2) active galactic nuclei (AGN) observed by XMM-Newton in targeted observations, whose data are public as of March 2007. With its 156 sources, this is the largest catalogue of high signal…
Evidence of a long-term trend in total solar irradiance
Fröhlich, C.
Aims: During the solar minimum of 2008, the value of total solar irradiance at 1 AU (TSI) was more than 0.2 Wm-2 lower than during the last minimum in 1996, indicating for the first time a directly observed long-term change. On the other hand, chromospheric indices and hence solar UV irradiance do not exhibit a similar change.
Metho…
An X-ray view of 82 LINERs with Chandra and XMM-Newton data
Guainazzi, M.; Jiménez-Bailón, E.; González-Martín, O. +2 more
We present the results of a homogeneous X-ray analysis for 82 nearby low-ionisation, narrow emission-line regions (LINERs) selected from the catalogue of Carrillo et al. (1999, Rev. Mex. Astron. Astrofis., 35, 187). All sources have available Chandra (68 sources) and/or XMM-Newton (55 sources) observations. This is the largest sample of LINERs wit…
Binary planetary nebulae nuclei towards the Galactic bulge. II. A penchant for bipolarity and low-ionisation structures
Miszalski, B.; Moffat, A. F. J.; Parker, Q. A. +1 more
Considerable effort has been applied towards understanding the precise shaping mechanisms responsible for the diverse range of morphologies exhibited by planetary nebulae (PNe).
At least 10-20% of PNe have central stars (CSPN) with a close binary companion thought responsible for heavily shaping the ejected PN during common-envelope (CE) evol…Characteristics of solar-like oscillations in red giants observed in the CoRoT exoplanet field
Baudin, F.; Hatzes, A. P.; Baglin, A. +6 more
Context: Observations during the first long run (~150 days) in the exo-planet field of CoRoT increase the number of G-K giant stars for which solar-like oscillations are observed by a factor of 100. This opens the possibility to study the characteristics of their oscillations in a statistical sense.
Aims: We aim to understand the statistical d…
High-precision density measurements in the solar corona. I. Analysis methods and results for Fe XII and Fe XIII
Young, P. R.; Mariska, J. T.; Hara, H. +1 more
Aims: The EUV Imaging Spectrometer (EIS) instrument on board the Hinode satellite has access to some of the best coronal density diagnostics, and the high sensitivity of the instrument now allows electron number density, N_e, measurements to an unprecedented precision of up to ±5% in active regions. This paper gives a thorough overview of data ana…
The bolometric luminosity of type 2 AGN from extinction-corrected [OIII]. No evidence of Eddington-limited sources
Perola, G. C.; Bianchi, S.; Barcons, X. +3 more
Context: There have been recent claims that a significant fraction of type 2 AGN accrete close to or even above the Eddington limit. In type 2 AGN, the bolometric luminosity (L_b) is generally inferred from the [OIII] emission line luminosity (L_OIII). The key issue in estimating the bolometric luminosity in these AGN, is therefore to know the bol…