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XMM-Newton Observations ofNarrow-Line Seyfert 1 Galaxies
Luigi GalloMax-Planck-Institut für extraterrestrisch Physik
Many thanks to my advisors and collaborators: Y. Tanaka, Th. Boller, A. Fabian,
N. Brandt, S. Vaughan, G. Miniutti
Ringberg, 11 Apr. 2005 Luigi Gallo 2
Outline:
1. What are NLS1?2. XMM-Newton discovery of
sharp high-energy spectral drops 3. IZw1: lines and hard X-ray flares4. Flare model for NLS15. Other extreme observations
Ringberg, 11 Apr. 2005 Luigi Gallo 3
Narrow-line Seyfert 1s: What are they?
�FWHM(Hβ) < 2000km/s
�[OIII]λ5007/Hβ < 3
�strong FeII emission
� ~ 15% of optically selected samples (e.g. Williams et al. 2002)� upto 50% of soft X-ray selected samples (e.g Grupe 1996)
Ringberg, 11 Apr. 2005 Luigi Gallo 4
Extreme X-ray behaviourIRAS13224-3809
IRAS13349+2438
PHL 1092
RE J1034+393
Ringberg, 11 Apr. 2005 Luigi Gallo 5
NLS1 are extreme, but not unique!
Gallo, Boller, Voges et al. (2004)Grupe (2004)
Brandt & Boller 1998
NLS1 and BLS1 form a continuous sequence in parameter space.
Ringberg, 11 Apr. 2005 Luigi Gallo 6
XMM-Newton discovery of sharp spectral drops at E > 7 keV
IRAS 13224-3809 1H 0707-495
8.1 keV 7.5 keV
7 keV
Boller et al. (2003) Gallo et al. (2004)
� width is < 160 � 300 eV� no detection of accompanying Fe emission� drop energy changes with time
probably not due to photoionisation
Ringberg, 11 Apr. 2005 Luigi Gallo 7
Several discoveries...IRAS 13349+2438 (Longinotti et al. 2003) NGC4051 (Pounds et al. 04; Uttley et al. 04)
PG1402+261 (Reeves et al. 2004)PG1211+143 (Pounds et al. 2003)
see also Foschini et al. (2004); Grupe et al. (2004)...
Ringberg, 11 Apr. 2005 Luigi Gallo 8
Reflection and Light BendingFabian et al. (2004)
1H0707-495
Reflection dominatedspectrum
Continuumdominatedspectrum
Ringberg, 11 Apr. 2005 Luigi Gallo 9
Partial Covering (eg. Holt et al. 80, Tennant 89, Abrassart & Czerny 00, Tanaka et al. 04)
1H0707-495
Gallo et al. (2004)
IRAS 13224-3809
Boller et al. (2003)
„lumpy accretion“„patchy absorber“
and other formshard
soft
Ringberg, 11 Apr. 2005 Luigi Gallo 10
Partial covering or reflection?1H0707-495
2000
2002
Both models appear to work.Further observations can reveal the correct model!!!!
Ringberg, 11 Apr. 2005 Luigi Gallo 11
XMM-Newton observation of the prototype NLS1 I Zw 1
ratio
ASCA observation of IZw1Very broad, strong, highly ionised iron line present in the ASCA data (Leighly 1999; Reeves & Turner 2000)
Gallo et al. (2004)
XMM-Newton data allow for the existence of multiple narrow iron lines.
Ringberg, 11 Apr. 2005 Luigi Gallo 12
XMM-Newton detection of hard X-ray flaresI Zw 1 NAB 0205+024
Gallo et al. (2004)
Flare model (Galeev, Rosner, Vaiana 1979) seems particularly applicable to NLS1
Thanks to Rene Goosmann for figure
Ringberg, 11 Apr. 2005 Luigi Gallo 13
Hot-spot emission lines?NAB 0205+024
Neutral disc line froman annular emission region?
Gallo et al. (2004)Also in II Zw 177?
Gallo et al. submitted
Reflected component arising from a hard X-ray flare.
Ringberg, 11 Apr. 2005 Luigi Gallo 14
XMM-Newton discovery of other extreme behaviourShort-term variability in IRAS13224-3809
Gallo, Boller, Tanaka et al. (2004)
Hard band lags soft by 450 +/- 175 s
Possibly alternating lags:sometimes hard leads
Flux changes lead spectralvariability (hardness ratio)by 2000 +/- 1500 s
Ringberg, 11 Apr. 2005 Luigi Gallo 15
XMM-Newton discovery of other extreme behaviourShort-term variability in PHL 1092
Gallo, Boller, Brandt et al. (2004)
Impressive X-ray variability.Simultaneous UV variability? Short-term spectral variability
L0.4-10 = 10 erg/s !!!!! 45
Ringberg, 11 Apr. 2005 Luigi Gallo 16
Conclusions
Thank you!
� NLS1 are Seyfert 1 galaxies which show extreme behaviour
� XMM-Newton discovery of sharp spectraldrops at E > 7 keV � partial covering or reflection?
� flare model appears applicable to NLS1
XMM-Newton observations of NLS1 challenge our understanding of AGN, but at the same timeoffer a powerful laboratory for addressing these issues.