afea 1

1
The 2-10 keV variability properties of AGN in
the Lockman Hole
I. E. Papadakis, E. Chatzopoulos (University of
Crete) D. Athanasiadis, I. Georgantopoulos
(NOA) A. Markowitz (GSFC)
2

• X-ray variability properties of z0 AGN have
  been studied in detail the last 15 years.
• Variability amplitude decreases with increasing
  luminosity (Barr Mushotzky 1985, Lawrence
  Papadakis 1993, Green et al 1993, Nandra et al
  1997).
• The amplitude vs Lx anticorrelation is a
  byproduct of a more fundamental amplitude vs BH
  mass anticorrelation.

3

• s2?PSD(?)d?
• If
• ?break ?BHmass-1
• and
• PSDampconstant,

log(PSD)
?v-1
?v-2
log(?)
Then
4
O'Neill et al (2005)
Papadakis (2004)
5

... if one assumes that ltmgt0.1
6

• We considered the 10 XMM-Newton Lockman Hole
  observations (15/10 06/12 2002) of the 74 AGN
  with known z (Mateos et al, 2005).
• 66 of them have rest frame, 2-10 keV lightcurves
  with gt 5 points in them (Trf22.7 days).
• 53 sources showed significant variations (?2
  test).
• As a measure of the variability amplitude we
  used the s2nxs

7
s2nxs?Lx-0.80.1
s2nxs does not correlate with z
s2nxs?G31.2
8
zgt0.5 AGN are more variable than nearby AGN with
the same Lx
9
.
?break ?m/BHmass-1 (McHardy et al 2006)
The log(Lx)43-45, zgt0.5 AGN are more variable,
because they are less massive and m0.25-0.4
.
.
Interestingly, the s2 vs BHmass/m and the s2 vs
G relations imply a G vs ??mass/m relation.
.
10

• We plan to study the 2-10 keV variability
  properties of distant AGN using data from all
  possible surveys.
• We hope we will be able to estimate the average
  BHmass and m as a function of z.

.