Science Impacts of High Resolution X-Ray Spectroscopy

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Science Impacts of High Resolution X-Ray
Spectroscopy

• Chairs David P. Huenemoerder M. Nowak

Endorsers D. Dewey, N. S. Schulz, H. L.
Marshall C. R. Canizares (MIT)
N. Brickhouse J. Lee, J. Nichols (CfA)
T. Ayres (CASA)
M. Corcoran, S. Drake (GSFC)
T. Yakoob (Johns Hopkins)
A. Pollock (ESA)
The High-Energy Transmission Gratings on Chandra
and the Reflection Grating Spectrometers on
XMM-Newton have brought high spectral resolution
with high signal-to-noise to X-ray studies in a
wide variety of astrophysical fields. Such fields
include coronae of cool stars winds of hot
stars white dwarf and neutron star atmospheres
winds from active galaxies supernova remnants
and plasma in interstellar, intracluster and
intergalactic media. The goal of the session is
to introduce the science being performed with the
unique capabilities of high-resolution X-ray
spectroscopy satellites to a broad range of
astrophysicists. We will describe the scientific
advances made possible by high resolution X-ray
spectroscopy, and how these studies fit within
the context of both low-resolution, broad band
X-ray studies (i.e., Chandra and XMM CCD
spectroscopy, Suzaku, SWIFT, RXTE, and INTEGRAL)
and high-resolution spectroscopy at other
wavelengths (e.g., IR with Spitzer, and UV with
HST). Time will be available for discussion of
how these current missions are laying the
groundwork for future scientific work with
Constellation-X, which will be a high-resolution
X-ray spectroscopic mission. Ample time will be
devoted to discussion of science issues. In
addition, participants will receive a summary
of resources including at-meeting contacts for
off-line demonstrations and in-depth
discussions.
Cambridge, CfA, CUC Meeting Apr. 09 2008
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Science Impacts of High Resolution X-Ray
Spectroscopy
Talks X-Ray Spectroscopy of Photoionized
Plasmas T.
Kallman (GSFC)
Shocked Plasmas at high Dispersion
M. Gagne (W. Chester)
Posters (as presented)
Comparison of Spectral Capabilities of Current
X-ray Satellites (M. Nowak et al.)
A Catalog of Chandra Grating Spectra
(D. Huenemoerder et al.)
The HotGAS AGN HETG Data Facility and
Highlights Unique to X-ray Gratings (Yakoob et
al.) Probing AGN
Unific. with High-Res. Spectroscopic and Imaging
Obs. of NGC 2110 (Evans et al.)
Chandra Gratings Observations of the
Focused Wind in Cygnus X-1/HDE 226868 (Wilms et
al) Modelling The
X-Ray Spectra of the SS 433 Jets (Marshall et
al.) Chandra HETG
Large Program on the Magnetic CV EX Hya (Luna et
al.) Chandra HETG
Spectra Of SN 1987A At 20 Years (Dewey et al.)
Coronal Structures in the
Active Binary System CC Eri (Osten et al.)
The HETG Orion Legacy Project
(Schulz et al.) Status
of Coll. Ioniz. Equil. Calcs and a New Approach
to EM Determinations (Bryans et al)
Speeding Up Calculations of The
Non-equilibrium Ionization Model (Ji et al.)
Improved Wavelength
Accuracy for Reprocessed Grating Data (Nichols
et al.)
Cambridge, CfA, CUC Meeting Apr. 09 2008
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T. Kallman (NASA/GSFC)

• X-ray Spectroscopy of Photoionized Plasmas

A Picture is worth a thousand words
(Bonaparte?)
..but a spectrum is worth a thousand pictures..
(Ferland)
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What is high resolution spectroscopy?
I shall not today attempt further to define the
kinds of material I understand to be embraced . .
. but I know it when I see it .. Justice
Potter Stewart 1964
Con-x
RXTE
epic
RGS
HETG
gt Rgt500 allows discrimination of He-like
triplets, measurements of widths lt 600 km/s
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Why study spectra at high resolution?

• Puts the physics in astrophysics
• High resolution spectra ltgt line and edge
  features due to atomic transitions
• Spectroscopy allows study of sources on small
  spatial scales
• Chance to get detailed quantitative results on
• Abundances
• temperature
• kinematics
• But what we really want to study are the Exotic
  effects
• Relativity
• magnetic processes (Blandford-Znajek, Poynting
  flux)
• Whats really going on close to compact objects,
  (eg. M/R for neutron star, a/m for black hole).
• We have to understand the atomic spectra first in
  order to get to these

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topics

• AGN warm absorbers
• Warm absorbers close to home
• High Mass X-ray binaries
• ISM/IGM
• CVs
• Apologies to the many topics not discussed

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(Kaspi et al 2002)
Chandra HETG Spectrum NGC 3783

• 900 ksec observation
• gt100 absorption features
• blueshifted, v600 km/s
• broadened, by300 km/s
• fit to 2 photoionization model components

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The reality of spectroscopy it requires long
observations

• Typical fluxes (eg. For an AGN) 0.02
  photons/cm2/s Fmcrab
• Grating effective area 10-100 cm2
• Need 103 energy channels
• 10 photons/channel
• --gt tobs 5 105 s Fmcrab-1 A10-1

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CONCLUDING REMARKS

• Spectroscopy is where the physics is.
• Grating spectroscopy has boosted X-Ray Astronomy
  to level with other branches of astronomy and
  contributed to all fields of astrophysics
• AGN outflows clues to the global mass budget
• Measuring column densities in emission gt
  unifying Seyfert 1 absorber with Seyfert 2
  emitter
• Abundance studies detecting trace iron-peak
  elements from compact binaries
• Kinematics Discerning binary and non-thermal
  motion in binary systems, detecting outflows
• Detecting cold material and reflection geometry
  near compact objects
• Searching for our galactic halo and intergalactic
  gas
• This is challenging, and time consuming, but the
  insights are unique
• We need to continue to obtain grating
  observations, and to improve models to aid in
  their interpretation.

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Shocked Plasmas at High Dispersion

• Marc GagnéWest Chester University
• David CohenSwarthmore College
• Stan Owocki, Rich Townsend, Asif ud
  DoulaUniversity of Delaware
• Leisa Townsley, Pat Broos, Eric FeigelsonPenn
  State University

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Stellar X-ray shocks summary

1. X-ray line diagnostics
2. Rf/i He-like forbidden-to-intercombination line
   ratios
3. Line broadening, shifts, asymmetries
4. Accretion shocks on T Tauri stars TW Hya (K8
   Ve)
5. Wind shocks around massive stars
6. Line driving, shocks early-O supergiants ? Pup
   (O4 If)
7. Magnetically channeled wind shocks ?1 Ori C
   (O5.5 V)
8. Colliding-wind binaries WR 140 (WC7 O4)
9. New t Sco (B0 V), ß Cru (B0.5 IV), ?2 Ori A
   (O9.5 V), CEN 1A and 1B (O4 visual binary in
   M17)
10. Continuum diagnostics, non-equilibrium effects

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H-like/He-like ratio is temperature
sensitive He-like ratio Rf/i is a
density/dilution diagnostic
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Stellar X-ray shocks Conclusions

1. X-ray shocks in most O-type supergiants appear to
   form in clumpy winds.
2. Magnetically channeled wind shocks tend to occur
   in mid-O to early-B stars in very young clusters.
3. Colliding wind shocks require very high mass-loss
   rates the CEN 1 stars in M17 may be the youngest
   known CWS binaries.
4. TW Hya and other T Tauri stars appear to have
   accretion-driven X-ray shocks.
5. So far, we see no clear evidence of temperature
   non-equilibration or non-ionization equilibrium
   in the post-shock, X-ray emitting plasmas of hot
   stars.