Model: Mike Truss Visualisation: Richard West
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Transcript of Model: Mike Truss Visualisation: Richard West
Model: Mike Truss Visualisation: Richard West
Accretion in non-magnetic cataclysmic variables
Peter Wheatley
University of Warwick
Still et al 2010V344 Lyr
Kepler GO highlight
RXTE ASMRemillard et al 2009
X-ray transients
Ricketts, King & Raine 1979SS Cyg with Ariel V
Wheatley, Mauche & Mattei 2003
outburstquiescence
Patterson & Raymond 1985
Mukai et al., 2003Chandra HETG spectra
Mukai et al., 1997HT Cas eclipse with ASCA
Z Cha with XMM-Newton
Hickman, Wheatley et al. 2010
Optical: B band
0.2-12 keV
WD eclipse
Z Cha optical eclipse Hickman, Wheatley et al. 2010
B band
1.2-10 keV
0.2-1.2 keV
Hickman, Wheatley et al., 2010Z Cha X-ray eclipse
X-ray spectra
quiescence outburst
Patterson & Raymond 1985
Confirmed
SU UMa Collins & Wheatley 2009
4x1015g/s
Hamuery et al
Collins & Wheatley 2009
X-ray spectra
quiescence outburst
Patterson & Raymond 1985
Confirmed
Naylor et al. 1988OY Car in outburst with EXOSAT LE
7-250 Å
Chandra EUV spectra of dwarf novae in outburstMauche 2004
WZ Sgehigh inclination
SS Cyglow inclination
Lbl~1034 erg s-1 NH~3x1019 cm-2 V~2500 km s-1
X-ray spectra
quiescence outburst
Patterson & Raymond 1985
Confirmed Confirmed
NH~3x1019 cm-2
QPOs in dwarf nova outburstsMauche 2004
Belloni et al 2002
Mauche 2004
Warner & Woudt 2002
X-ray spectra
quiescence outburst
Patterson & Raymond 1985
Confirmed Confirmed
NH~3x1019 cm-2
?
Z Cha in outburst with XMM-Newton
outburst
quiescence
XMM-Newton spectra of Z Cha
outburst
quiescence
Outburst spectrum
Origin of outburst X-rays?
Lx <= 10-3 LBol
MRI-driven accretion disc corona? Shocks in outflows/jets?
Knigge et al 1997Z Cam with HUT
Koerding et al 2008
Okada et al 2008SS Cyg in outburst and quiescence
MAXI
Revnivtsev et al 2006
Sazonov et al 2006X-ray luminosities of SDSS-selected CVsReis, Wheatley et al 2010
Swift
Galactic ridge X-ray emission
Revnivtsev et al 2009
Byckling et al 2010
Summary
• Disc instability model:– under predicts quiescent accretion rate by >100x
– fails to explain outbursts in SS Cyg
• Origin of outburst X-ray emission unknown– MRI-driven corona?
– Shocks in outflows/jets?
• Jets, outflows and QPOs all detected in CVs– models for BHs/NSs must also work for white dwarfs
• Galactic ridge X-ray emission:– contribution of non-magnetic CVs previously underestimated