1 / 13

The Nature of the Doppler Lines in the Ultra-compact Binary

The Nature of the Doppler Lines in the Ultra-compact Binary 4U1626-67. Doppler Lines and Fe Fluorescence in the Ultra-compact Binary 4U1626-67. Previous HETG GTO observations:

amcnatt
Download Presentation

The Nature of the Doppler Lines in the Ultra-compact Binary

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Nature of the Doppler Lines in the Ultra-compact Binary 4U1626-67

  2. Doppler Lines and Fe Fluorescence in the Ultra-compact Binary 4U1626-67 Previous HETG GTO observations: - Schulz et al. 2001: Double Peaked X-ray Lines from the O/Ne-rich Accretion Disk in 4U 1626-67: OBSIDs 104, 39 ksec - Krauss et al. 2007: High Resolution X-ray Spectroscopy of the Ultra-compact LMXB Pulsar 4U 1626-67: OBSIDs 104, 39 ksec 3504, 97 ksec

  3. Doppler Lines and Fe Fluorescence in the Ultra-compact Binary 4U1626-67 • New HETG GTO observations: • Chakrabarty & Schulz 2009 Cycle 11 GO time: OBSIDs 11058, 80 ksec, Jan 14. 2010

  4. Doppler Lines and Fe Fluorescence in the Ultra-compact Binary 4U1626-67 • Tbnew (Powerlaw + Bbodyrad): • NH = 1.2x1021 cm-1 • AG = 0.0084 ph cm-2 s-1 • = 0.80 • Abb = 593 (R2km / D2kpc) • kTbb = 0.20 keV • Tbnew (Powerlaw + Bbodyrad): • NH = 1.2x1021 cm-1 • AG = 0.0384 ph cm-2 s-1 • = 1.19 • Abb = 83 (R2km / D2kpc) • kTbb = 0.48 keV

  5. Flares and Dips in the New Light Curve of 4U1626-67 Obsid 11058: Obsid 3504:

  6. Doppler Lines in the Ultra-compact Binary 4U1626-67

  7. Doppler Lines in the Ultra-compact Binary 4U1626-67

  8. Ionization Model Fits to the X-ray Spectrum of 4U1626-67 Photo-ionized modeling: Collisional-ionized modeling:

  9. Collisional Ionization Model Fits to the X-ray Spectrum of 4U1626-67 Aped_density = 13:

  10. Doppler Lines and Fe Fluorescence in the Ultra-compact Binary 4U1626-67 Pure C/O/Ne disk?: Cannot maintain C I/Ne I/O I : log x > 2 @ r~109 cm Pure C/O disk model predicts T = 28000 K @ 20000 km (Werner et al. 2006)

  11. Magnetospheric Accretion Shocks in the Ultra-compact Binary 4U1626-67 Emission Volumes:

  12. Doppler Lines in the Ultra-compact Binary 4U1626-67 In conclusion we propose the following: Rco = 8.5x108 cm Rco = Rmag Vshift ~ 2000 km/s ~ Vco Vco ~ Vshock Tjump < 60 MK CO plasma < 20 deg impact Vshift = Vion Tshock < 10 K Magnetospheric Accretion Shocks

  13. Doppler Lines in the Ultra-compact Binary 4U1626-67 In conclusion we propose the following: • The light curve before torque reversal is featureless. The light curve after torque reversal shows enhance variability which includes type II flaring, intensity dips, and periods of quiescence. • The X-ray flux at the time of the observation in 2009 is at about the same level as it was in 1994. • The X-ray continuum after torque reversal is fit by the same spectrum as before, however with a higher blackbody temperature and a smaller emission radius . • The spectrum shows a narrow Fe K fluorescence line, which was not observed before torque reversal. • A photo-ionized plasma cannot fit the Ne and O Doppler line emissions. • The large ratio between the Ne X Lα line and the upper limit to the Ne X Lβ line rules out significant contributions due to resonance scattering . • A collisions ionized plasma fits both Ne and O line ratios very well with enhanced plasma densities and plasma temperature between 1 MK and 10 MK. Magnetospheric Accretion Shocks

More Related