Table 3 summarizes the ASCA observations. The GIS data were obtained with the normal PH mode, and the SIS data using the BRIGHT2 1 CCD mode. The targets were centered at the nominal position of the 1 CCD mode, which causes a slight position offset on the GIS images. All the subsequent analysis has been carried out with the XSPEC_8.5 and FTOOLS_3.5 packages using the screened data provided by the ASCA Standard Analysis from NASA/GSFC.
An elliptical region has been selected for extracting the SIS/GIS spectra of A 1300 and an circular region for A 1732; this is shown in Fig. 1 and Fig. 2. For both objects, the background area was selected in the vicinity of the source but excluding the cluster outskirts (beyond 8' from the source center). In an attempt to improve signal-to-noise, we have also used background spectra from blank-sky fields, since both clusters are in the direction of moderate . This did not lead to a significant improvement in the spectral fit accuracy (see Table 4). Note, also, that blank-sky observations are presently available only for the GIS detector and not for the SIS in the BRIGHT2 1 CCD mode.
In addition, we made use of our 8.6 ks ROSAT PSPC observation of A 1300 to complement the spectral analysis.
|Figure 1: SIS image of A 1300 in the [0.4-10] keV band. The pixel size is 6.3'' and the image has been filtered by a Gaussian having a of 1.5 pixel. Contours levels are 1.0, 2.0, 3.0... counts/pixel. The region extracted for the spectrum is indicated by an ellipse|
|Figure 2: SIS image of A 1732; otherwise as for Fig. 1|
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