Spectrum-X Gamma vs. Other X-ray Observatories
A comparison of the energy resolution
of the high resolution spectrometers on the X-ray telescopes
CHANDRA, XMM-NEWTON, and SODART is shown below. For XMM, curves are shown
for the RGS2 only, the better one of the two grating sets.
To avoid confusion, the CHANDRA-LEG curves are shown in the
low-energy region only (<0.4 keV), although they can be used
in the whole energy region (<10 keV). The dotted parts of the
SODART curves indicate energy regions, where the Bragg
spectrometer can still work, but its efficiency drops down
due to a very large or very small Bragg angle.
(From Wiebicke, H. 2000, Proc. SPIE, in preparation)
It should be noted that these curves apply to point sources. Although
the SODART Bragg Spectrometer maintains its full energy resolution and
resolving power for extended sources, the performance of the Chandra
LEG
and
HEG
and XMM-Newton
RGS spectrometers is significantly degraded for extended sources.
![[Comparison of X-ray Observatories' Energy Resolution]](./images/enres.gif)
Click here to
retrieve a full-size
postscript plot (external viewer required).
A comparison of the resolving power
of the high resolution spectrometers on the X-ray telescopes
CHANDRA, XMM-NEWTON, and SODART is shown below. For XMM, curves are shown
for the RGS2 only, the better one of the two grating sets.
To avoid confusion, the CHANDRA-LEG curves are shown in the
low-energy region only (<0.4 keV), although they can be used
in the whole energy region (<10 keV). The dotted parts of the
SODART curves indicate energy regions, where the Bragg
spectrometer can still work, but its efficiency drops down
due to a very large or very small Bragg angle.
(From Wiebicke, H. 2000, Proc. SPIE, in preparation)
It should be noted that these curves apply to point sources. Although
the SODART Bragg Spectrometer maintains its full energy resolution and
resolving power for extended sources, the performance of the Chandra
LEG
and
HEG
and XMM-Newton
RGS spectrometers is significantly degraded for extended sources.
![[Comparison of X-ray Observatories' Energy Resolution]](./images/respow.gif)
Click here to
retrieve a full-size
postscript plot (external viewer required).
A plot of the effective areas of some SXG telescope/instrument
combinations compared to those of other X-ray observatories is shown
below.
![[Comparison of X-ray Observatories' Effective Areas]](./images/mission_comparisons_sxg.gif)
The plot labels are
SXG LEPC - SXG SODART Telescope (one of two MM's) plus LEPC detector
SXG HEPC - SXG SODART Telescope (one of two MM's) plus HEPC detector
ACIS back - AXAF-I Telescope with back-illuminated ACIS CCD
ACIS front - AXAF-I Telescope with front-illuminated ACIS CCD
PSPC - ROSAT PSPC
IPC - Einstein IPC
Click here to
retrieve a full-size
postscript plot (external viewer required).
Comments? Send mail to:
sxg@cfa.harvard.edu
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Last Updated 14-Apr-2000