The AE Aqr Multi-wavelength Campaigns Zach Ioannou (SQU) BELISSIMA Conference 18-21 September 2012.
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The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
Patterson (1979): Oblique Rotator
WKH (1997): Diamagnetic Blobs Terada et al. (2008): Cosmic Ray Accelerator
E&H (1996), WHG (1998), Meintjes et al. (2000): Magnetic propeller
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
The 2012 Campaign
★:CBA &AAVSO
KVA
Vidojevica
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
2005 Campaign 2012 Campaign
1. C.W. Mauche (LLNL, USA) 1. C.W. Mauche (LLNL, USA)
2. M. Abada-Simon (Obs. Paris, France) 2. Rubén López-Coto (IFAE, Spain)
3. J.-F. Desmus (OAN, Spain) 3. Z. Ioannou (SQU, Oman)
4. Z. Ioannou (Crete, Greece) 4. M. Bogoslavljevic (AOB, Serbia)
5. M.J. Dulude (SDSU, USA) 5. E. Lindfors (Tuorla, Finland)
6. W.F. Welsh (SDSU, USA) 6. A. Henden (AAVSO)
7. J.D. Neil (Caltech, USA)
8. N. Sidro (IFAE, Spain)
9. A. Price (AAVSO)
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
Sep 2Sep 1Aug 31Aug 30Aug 292005 UT
Chandra
GALEX
SWIFT
VLA
HESS
MAGIC
SALT
Skinakas
WHT
Laguna
The 2005 Campaign
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
The 2012 Campaign
Observations consist of just a 30 min window per day
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
Z. IoannouW. F. WelshM. J. Dulude
M. Abada-SimonJ.-F. Desmurs
CBAAAVSOA. Price
1530 Å
2270 Å
C. W. Mauche
C. W. MaucheJ. D. Neill
Correlated flaresand the 33 s white dwarf spin pulseare observed in theoptical through X-ray wavebands
The radio light curveis uncorrelated withthe other wavebands,implying that the radio flux is due to indepen-dent processes
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
Spin phase offset variations correspond toa pulse time delay of a sini = 2.17±0.48 s*
Phase offset relative to the de Jager et al.spin ephemeris of 0.237 ± 0.010 cycles
X-ray source follows the motion of the whitedwarf around the binary center of mass
White dwarf is spinning down at a rate thatis slightly less than that predicted by the
de Jager et al. (1994) quadratic ephemeris
*de Jager (1995) derived a sini = 2.04±0.13 s
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
Spectrum is reasonably well fit by a Gaussian emission measure distribution with a peak at log T(K) = 7.16, a width σ = 0.48, Fe/Fe = 0.44, other metals Z/Z = 0.76, EM = 8x1053 cm-3, and Lx = 1x1031 (d/100 pc)2 erg s-1
Mauche (2009, ApJ, 706, 130)
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
Radial velocities don’t appear to vary on thewhite dwarf orbit phase!
Radial velocities vary on the white dwarf 33 sspin phase, with two oscillations per cycle
(b) composite line profile technique(c) cross-correlation technique(d) boot-strapped cross-correlation technique
(a) composite line profile technique
X-ray plasma is trapped on, and rotates with, the white dwarf’s dipolar magnetic field
This is an unexpected result, but differs from the predicted radial velocity of the white dwarf (gray shading) by only 2.3σ
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
• AE Aqr was observed with the 17 m MAGIC telescope on 4 consecutive nights in 2005 August 29−September 1, and for 24 nights in 2012 at zenith angles of 300−500, for a total of >30 hr.
Analysis of each of the nights: no steady excess emission.
Analysis of the sum of the nights: no steady excess emission.
Periodic analysis of each night, using (a) the Rayleigh test on frequencies around the pulse frequency ν0 and 2ν0 and (b) phase-folding on frequencies near ν0 and 2ν0: no excess emission.
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
Suggesting the possibility that, contrary to previous claimsand common belief, AE Aqr is not a TeV gamma-ray source
*Lang et al. (1998, Astroparticle Physics, 9, #3, 203)
No detections on the sum of the 4 nights from 2005:
*
F(E
>E
0)
[10-1
1 c
m-2s-1
]
Whipple*
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
• The (pulsating component of the) source of X-rays in AE Aqr follows the motion of the white dwarf around the binary center of mass.
• Contrary to the conclusions of Itoh et al. (2006), the majority of the plasmain AE Aqr has a density ne>1011 cm-3, hence its spatial extent is orders of magnitude less than their estimate of 5x1010 cm.
• The radial velocity of the X-ray emission lines varies on the white dwarf 33 s spin phase, with two oscillations cycle and an amplitude K ≈ 160 km s-1, broadly consistent with plasma tapped, and rotating with, the white dwarf’s dipolar magnetic field.
• These results are inconsistent with recent models* of an extended, low-density source of X-rays in AE Aqr, but instead support earlier models in which the dominant source of X-rays is of high density and/or in close proximity to the white dwarf.
• AE Aqr is not a TeV gamma-ray source.
*Meintjes (2000); Itoh et al. (2006); Ikshanov (2006); Venter & Meintjes (2007)
The AE Aqr Multi-wavelength Campaigns
Belgrade, 20th September 2012
• 2005 Campaign:
(18) Optical Telescopes
(2) γ-ray
(1) Radio
(3) Satellites
• 2012 Campaign:
(7) Optical Telescopes
(1) γ-ray
(1) Satellite
★:CBA &AAVSO
★:CBA &AAVSO
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