All Figures

Figure 1: Overlay of the J=1-0 13CO integrated line intensity, shown as thick contours, starting at 4 K km s-1, in steps of 2 K km s-1 to 18 K km s-1 (from Wilson et al. 1993) on 450 m sub-mm dust emission image, shown as thin contours (from Dunne et al. 2003). The B1950.0 coordinates are taken from Wilson et al. (1993). See Fig. 2 for a map of a larger region in the CO J=2-1 line. We have numbered the sub-mm dust emission maxima 1 to 6. The 13CO clouds are labeled with capital letters A to H. Shaded circles show the FWHP and location of 13CO  clouds (from Wilson et al. 1993). The sub-mm dust peaks under E and F do not have higher contours for clarity. The thick dotted lines mark the boundaries where we have divided the sub-mm dust emission between peaks 2, 3, 4, and 5. We used these as the boundaries of integrations to determine the masses of individual regions.

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In the text

Figure 2: Adapted from Liszt & Lucas 1999; the coordinates are B1950.0. The gray scale is the J=2-1 CO emission toward Cas A, summed from V=-30 to -50 km s-1. The wedge on the right side of the image, with numbers from 1 to 33, is the scale for integrated intensity in units of K km s-1. The white crosses indicate where spectra were taken with longer integrations by Liszt & Lucas (1999). The range of radial velocity is basically the same as that used to form the 13CO image, shown as thick contours in Fig. 1. The angular resolution of the CO data is 28 . The black contours are the 140 GHz continuum from the SNR Cas A measured by Liszt & Lucas 1999, with angular resolution 44 . This is dominated by synchrotron emission. We have superposed the sub-mm dust emission contours from Fig. 4 of Dunne et al. (2003) as white contours. This image shows that most of the CO is located south of Cas A, as is the sub-mm dust emission. The 13CO  extent (Fig. 1) is smaller than that of the CO because of lower optical depth.

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In the text

Figure 3: Adapted from Troland et al. 1985 (resolution 2.5'). The three panels show the radial velocities which contribute to the CO emission. In the upper three sketches, the coverage of the CO emission over the face of Cas A is shown. As in Fig. 2, most of the CO emission is to the south of the center of Cas A. In each lower panel the thin circle at offset (0,0) marks the edge of the continuum emission from Cas A. The FWHP beam is shown in the upper right of the V=-47 km s-1 panel. The contour units are peak line intensity in K. The thick square box in this panel shows 1.2 times the boundaries of the 450 m sub-mm dust continuum map of Dunne et al. 2003. These data show that the clouds covering the southern part of Cas A are the edges of larger molecular clouds.

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In the text