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2 Observations and data reduction

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.


  
Table 3: Journal of observations

\begin{tabular}
{\vert\vert l\vert l\vert c\vert c\vert c\vert c\vert\vert} \hli...
 ...4.6~~0.14 & 44.1~~0.12 & 46.4~~0.093 &
46.3~~0.12 \\  \hline \hline\end{tabular}
The countrates have been integrated within a radius of 500'' in the [0.7-10] keV band for the GIS images and within a radius of 250'' in the [0.4-10] keV band for the SIS.

The ROSAT images of A 1300 and A 1732, filtered by a wavelet multi-resolution algorithm with a rigorous treatment of photon noise (Starck & Pierre 1998), are shown in Lémonon et al. (1997) and Pierre et al. (1996) respectively. At the ASCA angular resolution, A 1732 does not show significant structure as already inferred from the 30 ks HRI pointing which revealed a very regular morphology and a moderate cooling flow of $\sim 200$  $M_{\odot}$/year. A 1300, on the other hand, is clearly elongated, in good agreement with the PSPC observation that was used to infer the post-merger state of the cluster; no HRI image is available for this cluster.

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 $N_{\rm H}$. 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.


  
Table 4: Results from the spectral analysis; errors are given for a 90% confidence interval. Rest frame absorption corrected luminosities have been calculated from the GIS countrate using the temperatures and metallicities obtained by ASCA (this table) and $N_{\rm H}$ values listed in Table 2

\begin{tabular}
{\vert\vert l\vert l\vert l\vert l\vert l\vert c\vert\vert} \hli...
 ... & $0.2 
9_{-0.07}^{+0.09}$\space & 0.97 & \\ [0.5mm] \hline \hline\end{tabular}
* Indicates that the GIS spectra were extracted using a background from blank-sky observations, otherwise the background has been routinely estimated from our images using regions free of sources.

  
\begin{figure}
\psfig {file=aas1622f1.eps,width=9cm}\end{figure} 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 $\sigma $ 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

  
\begin{figure}
\psfig {file=aas1622f2.eps,width=9cm}\end{figure} Figure 2: SIS image of A 1732; otherwise as for Fig. 1

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