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A (short) review of the talks and posters presented

A (short) review of the talks and posters presented. Randall Smith JHU & NASA/GSFC. Spectroscopy puts most of the “physics” into X-ray astrophysics. – Claude Canizares. 1895 ApJ, 1, 1:. A. A. Michelson on how to measure spectral lines emitted in solar prominences.

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A (short) review of the talks and posters presented

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  1. A (short) review of the talks and posters presented Randall Smith JHU & NASA/GSFC

  2. Spectroscopy puts most of the “physics”into X-ray astrophysics – Claude Canizares

  3. 1895 ApJ, 1, 1: A. A. Michelson on how to measure spectral lines emitted in solar prominences

  4. “Synthesize, don’t Summarize” • Methods & Models • Accretion (WA, Fe K) • Stars – flares & FIPs, O (-type) my! • Expect the Unexpected • Future of X-ray Spectroscopy

  5. What didn’t we talk about? (much) • SNRs (except Dewey) – and we clearly need to re-observe Cas A in 6-7 years • Clusters (except Peterson, Behar) – although absence of cooling flows a blockbuster; also found vturb<30 km/s with a 300 km/s spectrometer!

  6. What didn’t we talk about? (much) • SNRs (except Dewey) – and we clearly need to re-observe Cas A in 6-7 years • Clusters (except Peterson, Behar) – although absence of cooling flows a blockbuster; also found vturb<30 km/s with a 300 km/s spectrometer! We need non-dispersive X-ray spectra!

  7. Methods & Models Some things are easy. [Thank goodness!] • Identifying ion parent of (most) lines • Fe L shell lines easy to id; strengths harder • RRC features mostly easy to id as well. • Doppler shifts (if  known well; need lab data!) • But getting v to 3.7 km/s in EX Hya impressive • Diagnostic line ratios of (strong) lines • But watch out for LOS differences in models!

  8. Methods & Models Others are hard • Fitting high-resolution broad band spectra • Measuring a faint continuum • Determining an Emission or Absorption Measure Distribution (EMD, AMD) • Creating a model simple enough to calculate but powerful enough to encapsulate data

  9. Methods & Models Are we ready for a satellite which produces nothing but high-resolution X-ray spectra?

  10. Methods & Models: Analyzing high-resolution spectra • RGS, HETG, and LETG spectra all have more resolution elements than this projector! • Methods: Which converge? to the right value? • “Photon Clean,” including bootstrap • Line-Based Analysis • absline • Gaussian fits after continuum determination • Adding components until 2 stops dropping • Continuum finding: find line-free regions, assumed power-law, spline fit, other method? • What constitutes a “good” fit?

  11. Methods & Models: Analyzing high-resolution spectra • RGS, HETG, and LETG spectra all have more resolution elements than this projector! • Methods: Which converge? to the right value? • “Photon Clean,” including bootstrap • Line-Based Analysis • absline • Gaussian fits after continuum determination • Adding components until 2 stops dropping • Continuum finding: find line-free regions, assumed power-law, spline fit, other method? What is a “good” fit?

  12. Methods & Models: Analyzing high-resolution spectra Is the biggest problem: • atomic data? (20-30% correlated errors) • calibration? (3-15% correlated errors) • insufficient counts (what metric?) • methodology? (unknown...)

  13. Methods & Models • Accessing data getting easier: • BiRD for XMM RGS data http://xmm.esac.esa.int/BiRD/ • XATLAS for HETG stellar data http://cxc.harvard.edu/XATLAS • Profit for GUI spectral viewing • with ATOMDB or XSTAR line ids! http://heasarc.gsfc.nasa.gov/software/profit (+ CIELO for RGS/Sy1.5+, HotGAS for HETGS)

  14. Accretion: Introduction • Ubiquitous process • SMBH • Galactic BH • X-ray (NS) binaries • WD (CVs: baby Seyferts that become SSS when the corona collapses...) • Dynamic! (Winds, WA, etc) • M, Macc, Mwind, Router, Rinner, Spin • Inclination, Magnetic geometry . .

  15. Accretion: Questions, Asked or Answered • RRCs prove photoionization is the dominant process in some parts of accretion flows. • Broad Fe K lines in some AGN are real • But can we really measure the BH spin? • Soft X-ray excess coincides with optical NLR • WA: Clumpy or a continuous distribution? • Can we tell? Are models holding us back, or calibration, or the data? • Some X-ray components match UV ones (e.g NGC 7469), and they respond to changes in the source flux.

  16. Accretion: Questions, Asked or Answered • Hot Absorbers at High Velocities • Do they exist? Are we missing a giant component of mass outflow? • Regardless, X-ray observations show this component dominates UV flows ( > 90%) for nearby AGN. • NELG spectra not so flat ( ~ 1.7-1.8, not 1.4), no disk reflection seen (NGC 2110, 3C445)

  17. Stars: Flares & FIPs O (-type) My! • Static loop models have DEM  T1.0-1.5 • Observations show DEM  T4.0 • Which agrees with dynamic loop models • Flares in X-ray may be in optical or not • Abundances can change during flare. • CTTS seem to show accretion as well • Weak Fe K seen in HR 9024 flare; reflection model agrees with loop geometry.

  18. Stars: Flares & FIPs • (I)FIP is • Solved • Mysterious • Unexplained

  19. Stars: Flares & FIPs • (I)FIP is • Solved • Mysterious • Unexplained • Confusing all those not working in stars...

  20. Hot Stars: Controversy in the offing? O star lines are broad & symmetric(ish) • Resonant scattering? • Opacity? • Or from shocked protons & CX, while the electrons remain cold

  21. Expect the Unexpected • Measuring dust or molecular composition • Ferrous vs ferric iron? With X-rays from the Crab nebula? Yes! • Main limitation in seeing XAFS is data, both observational & experimental. • Did Alpha Cen A disappear? Nope, just got cooler–side benefit of the LETGS • X-rays can catch SS433’s jet hitting a bump • The hot gas seen at z~0 is really in the Galactic halo.

  22. Future of X-ray Spectroscopy • Velocity broadened lines detected with suggestion of both cold and collisional plasmas in the LLAGN M81; needresolution, EA! • Detect redshifted iron lines from surface of NS, determine EOS; need ... • Track material falling into AGN via Fe K; need...

  23. Future of X-ray Spectroscopy • Velocity broadened lines detected with suggestion of both cold and collisional plasmas in the LLAGN M81; needresolution, EA! • Detect redshifted iron lines from surface of NS, determine EOS; need ... • Track material falling into AGN via Fe K; need... • Con-X (and CAT) can give resolution, EA

  24. The Unified AGN Spectrum: NGC 3783!

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