Publications (33)
CIV and CIII] reverberation mapping of the luminous quasar PG 1247+267
D. Trevese, M. Perna, F. Vagnetti +2
So far the masses of about 50 active galactic nuclei have been measured through the reverberation mapping technique (RM). Most measurements have been performed for objects of moder…
Selecting AGN through variability in SN datasets
K. Boutsia, B. Leibundgut, D. Trevese +1
Variability is a main property of active galactic nuclei (AGN) and it was adopted as a selection criterion using multi epoch surveys conducted for the detection of supernovae (SNe)…
The Ensemble Variability Properties of Faint QSOs
D. Trevese, R. G. Kron, S. R. Majewski +2
A refined sample of 64 variable objects with stellar image structure has been identified in SA 57 to , over a time baseline of 15 years, sampled at 11 distinct epochs.…
A new search for variability-selected active galaxies within the VST SUDARE-VOICE survey: the Chandra Deep Field South and the SERVS-SWIRE area
S. Falocco, D. De Cicco, M. Paolillo +19
This work makes use of the VST observations to select variable sources. We use also the IR photometry, SED fitting and X-ray information where available to confirm the nature of th…
A multi-epoch spectroscopic study of the BAL quasar APM 08279+5255: I. C IV absorption variability
D. Trevese, F. G. Saturni, F. Vagnetti +3
Broad Absorption Lines indicate gas outflows with velocities from thousands km/s to about 0.2 the speed of light, which may be present in all quasars and may play a major role in t…
The XMM Deep Survey in the CDF-S VII. UV catalogue of the Optical Monitor observations
M. Antonucci, A. Talavera, F. Vagnetti +5
The XMM-Newton X-ray observatory has repeatedly observed the CDFS in 33 epochs (2001-2010) through the XMM-CDFS Deep Survey. During the X-ray observations, XMM-OM targeted the cent…
Large Scale Structures at High Redshift in the GOODS Field
M. Castellano, S. Salimbeni, D. Trevese +8
We present a catalogue of overdensities in the GOODS-South field. We find various high density peaks that are embedded in structures diffused on the entire field, up to z ~ 2.5. Th…
Ensemble X-ray variability of Active Galactic Nuclei from serendipitous source catalogues
F. Vagnetti, S. Turriziani, D. Trevese
The X-ray variability of the Active Galactic Nuclei (AGN) has been most often investigated with studies of individual, nearby, sources, and only a few ensemble analyses have been a…
Variability-selected Active Galactic Nuclei in the VST-SUDARE/VOICE Survey of the COSMOS Field
D. De Cicco, M. Paolillo, G. Covone +16
Optical variability has proven to be an effective way of detecting AGNs in imaging surveys, lasting from weeks to years. In the present work we test its use as a tool to identify A…
The Variability of Quasars. II. Frequency Dependence
A. Di Clemente, E. Giallongo, G. Natali +2
The variability of 30 PG quasars has been observed in the red band during three years. A rest-frame structure function analysis shows an increase of variability with the time inter…
SUDARE-VOICE variability-selection of Active Galaxies in the Chandra Deep Field South and the SERVS/SWIRE region
S. Falocco, M. Paolillo, G. Covone +18
One of the most peculiar characteristics of Active Galactic Nuclei (AGN) is their variability over all wavelengths. This property has been used in the past to select AGN samples an…
Color Variability of AGNs
F. Vagnetti, D. Trevese
Optical spectral variability of quasars and BL Lac Objects is compared by means of the spectral variability parameter beta (Trevese & Vagnetti 2002). Both kinds of objects change t…
Variability and the X-ray/UV ratio of Active Galactic Nuclei
F. Vagnetti, S. Turriziani, D. Trevese +1
The observed relation between the X-ray radiation from AGNs, originating in the corona, and the optical/UV radiation from the disk is usually described by the anticorrelation betwe…
M_1 - M* Correlation in Galaxy Clusters
D. Trevese, G. Cirimele, B. Appodia
Photographic F band photometry of a sample of 36 Abell clusters has been used to study the relation between the magnitude of the brightest cluster member and the Schechter fu…
Line and continuum variability of two intermediate-redshift, high-luminosity quasars
D. Trevese, D. Paris, G. M. Stirpe +2
It has been shown that the luminosity of AGNs and the size of their broad line region obey a simple relation of the type R=a L^g, from faint Seyfert nuclei to bright quasars, allow…
An X-ray underluminous cluster of galaxies in the 4Ms CDFS observations
M. Castellano, L. Pentericci, N. Menci +8
[Abridged] We use the large public spectroscopic database available in the GOODS-South field to estimate the dynamical mass and the virialization status of cluster ClG 0332-2747 at…
Optical spectral variability of PG QSOs
D. Trevese, F. Vagnetti
In previous studies we have shown that the optical variability of quasars increases, on average, with redshift. We explained this dependance in terms of a hardening of the spectrum…
A Comprehensive Study of Large Scale Structures in the GOODS-SOUTH Field up to z \sim 2.5
S. Salimbeni, M. Castellano, L. Pentericci +14
The aim of this paper is to identify and study the properties and galactic content of groups and clusters in the GOODS-South field up to z\sim2.5, and to analyse the physical prope…
An X-ray and Optical Study of Matter Distribution in the Galaxy Cluster A 2319
D. Trevese, G. Cirimele, M. De Simone
A new analysis of velocity distribution, optical photometry and X-ray surface brightness from ROSAT PSPC data of the galaxy cluster A 2319 is presented. The temperature profile der…
Variability-selected low luminosity AGNs in the SA57 and in the CDFS
F. Vagnetti, K. Boutsia, D. Trevese
Low Luminosity Active Galactic Nuclei (LLAGNs) are contaminated by the light of their host galaxies, thus they cannot be detected by the usual colour techniques. For this reason th…
A Photometrically Detected Forming Cluster of Galaxies at Redshift 1.6 in the GOODS Field
M. Castellano, S. Salimbeni, D. Trevese +9
We report the discovery of a localized overdensity at z~1.6 in the GOODS-South Field, presumably a poor cluster in the process of formation. The three-dimensional galaxy density ha…
Optical Spectroscopy of Active Galactic Nuclei in SA57
D. Trevese, V. Zitelli, F. Vagnetti +2
The cosmological evolution of X-ray-selected and optically selected Active Galactic Nuclei (AGNs) show different behaviours interpreted in terms of two different populations. The d…
A multi-epoch spectroscopic study of the BAL quasar APM 08279+5255 II. Emission- and absorption-line variability time lags
F. G. Saturni, D. Trevese, F. Vagnetti +2
The study of high-redshift bright quasars is crucial to gather information about the history of galaxy assembly and evolution. Variability analyses can provide useful data on the p…
Variability and the X-ray/UV ratio of active galactic nuclei. II. Analysis of a low-redshift Swift sample
F. Vagnetti, M. Antonucci, D. Trevese
Variability, both in X-ray and optical/UV, affects the well-known anti-correlation between the spectral index and the UV luminosity of active galactic nuclei, contributin…
An X-ray Survey in SA 57 with XMM-Newton
D. Trevese, F. Vagnetti, S. Puccetti +3
The maximum number density of Active Galactic Nuclei (AGNs), as deduced from X-ray studies, occurs at z<~1, with lower luminosity objects peaking at smaller redshifts. Optical stud…
The Gunn-Peterson Effect in the Spectrum of the Z=4.7 QSO 1202-0725: The Intergalactic Medium at Very High Redshift
E. Giallongo, S. D'Odorico, A. Fontana +5
A measure of the average depression between Lyman absorption lines in the spectrum of the faint quasar BR1202-0725 () is presented. The relatively high resolution of…
The luminosity function of cluster galaxies: relations among M_1, M* and the morphological type
D. Trevese, G. Cirimele, B. Appodia
A study of the luminosity function of 36 Abell clusters of galaxies has been carried out using photographic plates obtained with the Palomar 1.2 m Schmidt telescope. The relation b…
Spectroscopic follow-up of variability-selected active galactic nuclei in the Chandra Deep Field South
K. Boutsia, B. Leibundgut, D. Trevese +1
Luminous AGNs are usually selected by their non-stellar colours or their X-ray emission. Colour selection cannot be used to select low-luminosity AGNs, since their emission is domi…
Redshift Dependence of QSO Spectral Variability
F. Vagnetti, D. Trevese
We present a combined analysis of the optical spectral variability for two samples of QSOs, 42 objects at monitored at the Wise Observatory (Giveon et al 1999), plus 59 obj…
The red and blue galaxy populations in the GOODS field: evidence for an excess of red dwarfs
S. Salimbeni, E. Giallongo, N. Menci +8
We study the evolution of the galaxy population up to z\sim3 as a function of its colour properties. In particular, luminosity functions and luminosity densities have been derived…
Quasar Spectral Slope Variability in the Optical Band
D. Trevese, F. Vagnetti
We performed a new analysis of B and R light curves of a sample of PG quasars. We confirm the variability-redshift correlation and its explanation in terms of spectral variability,…
Variability-selected active galactic nuclei from supernova search in the Chandra deep field south
D. Trevese, K. Boutsia, F. Vagnetti +2
Variability is a property shared by virtually all active galactic nuclei (AGNs), and was adopted as a criterion for their selection using data from multi epoch surveys. Low Luminos…
Accretion, ejection and reprocessing in supermassive black holes
A. De Rosa, S. Bianchi, M. Giroletti +35
This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT f…