Matteo Guainazzi

ESA  XMM-Newton & Science Archives and VO Team


Since my Ph.D (Rome, October 1996), I have been mainly interested
in studying the high-energy emission of Active Galactic Nuclei
(AGN) in the local universe.

Recently, this research stream has led me to study the interaction
and feedback between the AGN and the circumnuclear gas on scales
from the parsec to the kilo-parsec, and their implication on AGN
structure models. Projects currently ongoing in this area are:

* the study of the X-ray properties of a radio-selected complete
  sample of Compact Symmetric Objects radio galaxies (mainly
  Giga-Hertz Peaked sources) aiming at establishing the effect of
  their dense gaseous environment on the evolution of small-scale
  radio jets. This project is carried on in cooperation with
  institutes in Cambridge (U.S.A) and Bologna (Italy)

* a systematic study of high-resolution observations (in the
  spatial and frequency domain) of obscured AGN. This study,
  carried out in cooperation with S.Bianchi during his two-year
  post-doc fellowship at ESAC, brought us to the following
  conclusions:
  - extended soft X-ray emission on scales 0.1-1 kpc is almost
    ubiquitous in nearby obscured AGN
  - this soft X-ray extended emission is primarily due to AGN
    photoionization, with an important contribution by resonant
    scattering
  - simple photoionization models impose a constant ionization
    parameter across the whole extension of the soft X-ray
    emission. This in turns implies a density radial dependence as
    the inverse square of the distance from the AGN, in agreement
    with AGN structure models, which foresee the presence of
    high-velocity, high-ionization disk outflows

It is foreseen that these projects will be continued in the future
with a growing involvement of Virtual Observatory tools and
technique, as dictated by my functional role as ESA-VO Scientist.
The most promising approach with I plan to follow in this direction
are:

* a systematic comparison of UV-to-X-ray spectral Energy
  Distributions of obscured AGN with models of star formation
  implemented as Theoretical Simple Access Protocol. This project
  is being conducted in cooperation with M.Cerviņo of the Istituto
  de Astrofisica de Andalucia

* a study of the radio.to-X-ray properties of the largest sample of
  GPS galaxies ever constructed, recently compiled by C.Vollmer
  (CDS, Strasbourg)

Recently, I have started a new XSA-based project: the statistical
study of the spectra of more than 100 unobscured AGN, aiming at:

- determining the fraction of AGN which exhibit signatures of X-ray
  illuminated relativistic disks. This number is crucial to
  establish if and in which measure the standard paradigm
  explaining the AGN energy output needs to be revised

* measuring the average properties of the accretion disk, on which
  relativistically broadened profiles depend: inclination, disk
  emissivity, black hole spin

A list of my most recent publications on refereed journals is
available at this link: <A
HREF="http://adsabs.harvard.edu/cgi-bin/nph-abs_connect?db_key=AST&qform=AST\u223c_query=YES&ned_query=YES&aut_logic=OR&obj_logic=OR&author=Guainazzi%2C+M.&object=&start_mon=10&start_year=2003&end_mon=12&end_year=2007&ttl_logic=OR&title=&txt_logic=OR&text=&nr_to_return=100&start_nr=1&jou_pick=NO&ref_stems=&data_and=ALL&group_and=ALL&start_entry_day=&start_entry_mon=&start_entry_year=&end_entry_day=&end_entry_mon=&end_entry_year=&min_score=&sort=SCORE&data_type=SHORT&aut_syn=YES&ttl_syn=YES&txt_syn=YES&aut_wt=1.0&obj_wt=1.0&ttl_wt=0.3&txt_wt=3.0&aut_wgt=YES&obj_wgt=YES&ttl_wgt=YES&txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1">link</A>.

There is plenty of room for colleagues, fellows and students to
cooperate in any of the above areas.