Publications (42)
UVBLUE: a new high-resolution theoretical library of ultraviolet stellar spectra
L. H. Rodriguez-Merino, M. Chavez, E. Bertone +1
We present an extended ultraviolet-blue (850-4700 AA) library of theoretical stellar spectral energy distributions (SEDs) computed at high resolution, R= 50,000. The UVBLUE grid, a…
ATLAS vs. NextGen model atmospheres: a combined analysis of synthetic spectral energy distributions
E. Bertone, A. Buzzoni, M. Chavez +1
We carried out a critical appraisal of the two theoretical models, Kurucz' ATLAS9 and PHOENIX/NextGen, for stellar atmosphere synthesis. Our tests relied on the theoretical fit of…
HST/ACS color-magnitude diagrams of candidate intermediate-age M 31 globular clusters. The role of blue horizontal branches
S. Perina, S. Galleti, F. Fusi Pecci +3
We present deep (V ~ 28.0) BV photometry obtained with the wide field channel of the Advanced Camera for Surveys on board HST for four M31 globular clusters that were identified as…
The horizontal branch morphology of M31 Globular Clusters
M. Bellazzini, A. Buzzoni, C. Cacciari +4
We present the results of a first global analysis of the Horizontal Branch morphology of Globular Clusters in the nearby spiral M31, based on their Color Magnitude Diagrams.
Open Clusters in the log Age vs. M_V plane
M. Bellazzini, S. Perina, S. Galleti +3
In the log Age vs. integrated absolute magnitude (M_V) plane, the open clusters of the Milky Way form a well-defined band parallel to theoretical sequences decribing the passive ev…
New insights on the accuracy of photometric redshift measurements
M. Massarotti, A. Iovino, A. Buzzoni +1
We use the deepest and most complete redshift catalog currently available (the Hubble Deep Field (HDF) North supplemented by new HDF South redshift data) to minimize residuals betw…
LBT/MODS spectroscopy of globular clusters in the irregular galaxy NGC 4449
F. Annibali, E. Morandi, L. L. Watkins +11
We present intermediate-resolution (R1000) spectra in the 3500-10,000 A range of 14 globular clusters in the magellanic irregular galaxy NGC 4449 acquired with the Mult…
An updated survey of globular clusters in M31. II Newly discovered bright and remote clusters
S. Galleti, M. Bellazzini, L. Federici +2
We present the first results of a large spectroscopic survey of candidate globular clusters located in the extreme outskirts of the nearby M31 galaxy. We obtained low resolution sp…
A critical appraisal of the SED fitting method to estimate photometric redshifts
M. Massarotti, A. Iovino, A. Buzzoni
We discuss the stability of the photometric redshift estimate obtained with the SED fitting method with respect to the choice of the galaxy templates. Within the observational unce…
New insights in high-resolution spectroscopy: a wide theoretical library of R=500000 stellar spectra
E. Bertone, A. Buzzoni, L. H. Rodriguez-Merino +1
We present an extended theoretical library of over 800 synthetic stellar spectra, covering energy distribution in the optical range (lambda = 3500-7000 angstrom), at inverse resolu…
The Vertical Structure of the Halo Rotation
T. D. Kinman, C. Cacciari, A. Bragaglia +2
New GSC-II proper motions of RR Lyrae and Blue Horizontal Branch (BHB) stars near the North Galactic Pole are used to show that the Galactic Halo 5 kpc above the Plane has a signif…
IR Colors and Sizes of Faint Galaxies
P. Saracco, S. D'Odorico, A. Moorwood +3
We present J and Ks band galaxy counts down to J=24 and Ks=22.5 obtained with the new infrared imager/spectrometer, SOFI, at the ESO New Technology Telescope. The co-addition of sh…
An updated survey of globular clusters in M 31. I. Classification and radial velocity for 76 candidate clusters
S. Galleti, L. Federici, M. Bellazzini +2
Aims - We present the first results of a large spectroscopic survey of globular clusters and candidate globular clusters in the nearby M~31 galaxy. The survey is aimed at the class…
A critical appraisal of ATLAS9 and NextGen 5 model atmospheres
E. Bertone, A. Buzzoni, M. Chavez +1
The fitting atmosphere parameters (Teff, g, and [Fe/H]) for over 300 stars in the Gunn & Striker and Jacoby et al. catalogs have been obtained relying on the Kurucz (1992) ATLAS9 a…
Massive young clusters in the disc of M31
F. Fusi Pecci, M. Bellazzini, A. Buzzoni +3
We have studied the properties of a sample of 67 very blue and likely young massive clusters in M31 extracted from the Bologna Revised Catalog of globular clusters, selected accord…
Spectral classification of stars using synthetic model atmospheres
E. Bertone, A. Buzzoni
We devised a straightforward procedure to derive the atmosphere fundamental parameters of stars across the different MK spectral types by comparing mid-resolution spectroscopic obs…
The Very Red Halo of the cD Galaxy in A3284
E. Molinari, A. Buzzoni, G. Chincarini
We present deep CCD surface photometry in the Gunn g, r, i system and spectroscopy of the cD galaxy at the centre of the cluster A3284 at z = 0.15. The brightness profile of the ga…
Spectral Indices of Stars at Super-solar Regime
A. Buzzoni, M. Chavez, M. L. Malagnini +1
We derived Lick narrow-band indices for 139 candidate super metal-rich stars of different luminosity class previously studied in Malagnini et al. (2000). Indices include Iron Fe50,…
An updated survey of globular clusters in M 31. III. A spectroscopic metallicity scale for the Revised Bologna Catalog
S. Galleti, M. Bellazzini, A. Buzzoni +2
We present a new homogeneous set of metallicity estimates based on Lick indices for 245 old globular clusters of the M31 galaxy comprised in the Revised Bologna Catalog. The metall…
The impact of encounters on the members of Local Group Analogs. A view from GALEX
L. M. Buson, D. Bettoni, L. Bianchi +3
The bright galaxy population of the Local Group Analog (LGA) LGG 225 has been imaged with the Galaxy Evolution Explorer (GALEX) through its Far- and Near-UV wavebands. A significan…
Bolometric correction and spectral energy distribution of cool stars in Galactic clusters
A. Buzzoni, L. Patelli, M. Bellazzini +2
We have investigated the relevant trend of the bolometric correction (BC) at the cool-temperature regime of red giant stars and its possible dependence on stellar metallicity. Our…
The horizontal branch morphology of M31 globular clusters. Extreme second parameter effect in outer halo clusters
S. Perina, M. Bellazzini, A. Buzzoni +4
We use deep, high quality colour magnitude diagrams obtained with the Hubble Space Telescope to compute a simplified version of the Mironov index [SMI; B/(B+R)] to parametrize the…
Synthetic Mid-UV Spectroscopic Indices of Stars
M. Chavez, E. Bertone, A. Buzzoni +4
Using the UVBLUE library of synthetic stellar spectra we have computed a set of mid-UV line and continuum spectroscopic indices. We explore their behavior in terms of the leading s…
The extended structure of the remote cluster B514 in M31. Detection of extra-tidal stars
L. Federici, M. Bellazzini, S. Galleti +3
We present a study of the density profile of the remote M31 globular cluster B514, obtained from HST/ACS observations. Coupling the analysis of the distribution of the integrated l…
ACS photometry of the globular cluster B514
S. Galleti, L. Federici, M. Bellazzini +2
We present deep F606W, F814W ACS photometry of the recently discovered globular cluster B514, the outermost known globular in the M31 galaxy. The cluster appears quite extended and…
PNe and H II regions in the starburst irregular galaxy NGC 4449 from LBT MODS data
F. Annibali, M. Tosi, D. Romano +7
We present deep 350010000 spectra of H II regions and planetary nebulae (PNe) in the starburst irregular galaxy NGC 4449, acquired with the Multi Object Double Spectrograph…
Planetary nebulae as tracers of galaxy stellar populations
A. Buzzoni, M. Arnaboldi, R. L. M. Corradi
We address the general problem of the luminosity-specific planetary nebula (PN) number, defined as alpha = N(PN)/L(gal), and its relationship with age and metallicity of the parent…
Evolutionary properties of the low-luminosity galaxy population in the NGC5044 Group
A. Buzzoni, S. A. Cellone, P. Saracco +1
With this third paper of a series we present Johnson-Gunn B,g,V,r,i,z multicolour photometry for 79 objects, including a significant fraction of the faintest galaxies around NGC504…
UV excess and AGB evolution in elliptical-galaxy stellar populations
Rosa A. Gonzalez-Lopezlira, A. Buzzoni
The puzzling origin of the ``UV-upturn'' phenomenon, observed in some elliptical galaxies, has recently been settled by identifying hot HB stars as main contributors to galaxy ultr…
GAUDI: a preparatory archive for the COROT mission
E. Solano, C. Catala, R. Garrido +34
The GAUDI database (Ground-based Asteroseismology Uniform Database Interface, http://sdc.laeff.esa.es/gaudi/) is a preparatory archive for the COROT (COnvection, ROtation and plane…
Lick Spectral Indices for Super Metal-rich Stars
A. Buzzoni, M. Chavez, M. L. Malagnini +1
The Lick Fe5015, Fe5270, Fe5335, Mgb and Mg2 indices are presented for 139 candidate SMR stars of different luminosity class studied in Malagnini et al. (2000). Evidence is found f…
Population synthesis at short wavelengths and spectrophotometric diagnostic tools for galaxy evolution
A. Buzzoni, E. Bertone, M. Chavez +1
Taking advantage of recent important advances in the calculation of high-resolution spectral grids of stellar atmospheres at short wavelengths, and their implementation for populat…
UB CCD photometry of the old, metal rich, open clusters NGC 6791, NGC 6819 and NGC 7142
G. Carraro, A. Buzzoni, E. Bertone +1
We report on a UV-oriented imaging survey in the fields of the old, metal-rich open clusters, NGC 6791, NGC 6819 and NGC 7142. These three clusters represent both very near and ide…
Synthetic and Observed Photometric Indices for Globular Clusters in the Galaxy and M31
S. Covino, L. E. Pasinetti Fracassini, M. L. Malagnini +1
Buzzoni's (1989) grid of synthetic spectral energy distributions, representative of old stellar populations, was used to derive colours in different photometric systems, and to com…
A Case Study of the May 30th, 2017 Italian Fireball
A. Carbognani, D. Barghini, D. Gardiol +25
On May 30th, 2017 at about 21h 09m 17s UTC a green bright fireball crossed the sky of north-eastern Italy. The fireball path was observed from some all-sky cameras starting from a…
Kinematic Structure in the Galactic Halo at the North Galactic Pole: RR Lyrae and BHB Stars show different kinematics
T. D. Kinman, C. Cacciari, A. Bragaglia +2
Space motions are given for 38 RR Lyrae (RRL) stars and 79 blue horizontal branch (BHB) stars in a ~200 deg2 area around the North Galactic Pole (NGP) using a homogeneous distance…
High-resolution spectroscopy of RGB stars in the Sagittarius Streams. I. Radial velocities and chemical abundances
L. Monaco, M. Bellazzini, P. Bonifacio +5
Context. The Sagittarius (Sgr) dwarf spheroidal galaxy is currently being disrupted under the strain of the Milky Way. A reliable reconstruction of Sgr star formation history can o…
New Model Atmospheres: Testing the Solar Spectrum in the UV
L. H. Rodriguez-Merino, O. Cardona, E. Bertone +2
We present preliminary results on the calculation of synthetic spectra obtained with the stellar model atmospheres developed by Cardona, Crivellari, and Simonneau. These new models…
Dust Absorption and the Cosmic UV Flux Density
M. Massarotti, A. Iovino, A. Buzzoni
We study the evolution of the galaxy UV luminosity density as a function of redshift in the Hubble Deep Field North (HDF-N). We estimate the amount of energy absorbed by dust and h…
The young stellar population at the center of NGC 205
L. Monaco, I. Saviane, S. Perina +5
Context. NGC 205 is a peculiar dwarf elliptical galaxy hosting in its center a population of young blue stars. Their origin is still matter of debate, the central fresh star format…
New Candidate EHB Stars in the Open Cluster NGC 6791: Looking Locally into the UV-upturn Phenomenon
L. M. Buson, E. Bertone, A. Buzzoni +1
Relying on U,B imagery at the Italian Telescopio Nazionale Galileo (TNG), we report here the discovery of a sample of 13 new UV-bright post-HB candidate stars in the field of the g…
Structure of the Galactic Halo towards the North Galactic Pole
T. D. Kinman, A. Bragaglia, C. Cacciari +2
We have used RR Lyrae and Blue HB stars as tracers of the old Galactic halo, in order to study the halo structure and the galactic rotation as a function of height above the plane.…