A (short) review of the talks and posters presented.ppt

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1、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,“Synthesize, dont Summarize”,Methods & Mod

2、els Accretion (WA, Fe K) Stars flares & FIPs, O (-type) my! Expect the Unexpected Future of X-ray Spectroscopy,What didnt 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;

3、also found vturb30 km/s with a 300 km/s spectrometer!,What didnt 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 vturb30 km/s with a 300 km/s spectrometer! We

4、need non-dispersive X-ray spectra!,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 im

5、pressive Diagnostic line ratios of (strong) lines But watch out for LOS differences in models!,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

6、to calculate but powerful enough to encapsulate data,Methods & Models,Are we ready for a satellite which produces nothing but high-resolution X-ray spectra?,Methods & Models: Analyzing high-resolution spectra,RGS, HETG, and LETG spectra all have more resolution elements than this projector! Methods:

7、 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”

8、fit?,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

9、components until 2 stops dropping Continuum finding: find line-free regions, assumed power-law, spline fit, other method?,What is a “good” fit?,Methods & Models: Analyzing high-resolution spectra,Is the biggest problem: atomic data? (20-30% correlated errors) calibration? (3-15% correlated errors) i

10、nsufficient counts (what metric?) methodology? (unknown.),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.nas

11、a.gov/software/profit (+ CIELO for RGS/Sy1.5+, HotGAS for HETGS),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 geo

12、metry,.,.,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? Ca

13、n 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.,Accretion: Questions, Asked or Answered,Hot Absorbers at High Velocities Do they exist? Are we missing a giant component of mass out

14、flow? 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),Stars: Flares & FIPs O (-type) My!,Static loop models have DEM T1.0-1.5 Observations show DEM T4.0 Which agrees w

15、ith 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.,Stars: Flares & FIPs,(I)FIP is Solved Mysterious Unexplained,Stars: Flares & FIPs,(I)F

16、IP is Solved Mysterious Unexplained Confusing all those not working in stars.,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,Expect the Unexpected,Measuring dust or molecular co

17、mposition 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 coolerside benefit of the LETGS X-rays can catch SS433s jet hitting a bump The hot gas seen at z0 is really in

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

19、 of X-ray Spectroscopy,Velocity broadened lines detected with suggestion of both cold and collisional plasmas in the LLAGN M81; need resolution, 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,The Unified AGN Spectrum:,NGC 3783!,