All Tables

Table 1: Basic properties of M 83 and M 51. $D_{25}\times d_{25}$ is the optical diameter from the RC3 catalogue. $L_{\rm FIR}$ is the surface integrated far-infrared luminosity between 42.5 and 122.5 $~\mu$ m using the listed distance. F₆₀/F₁₀₀ is the IRAS color ratio of the surface integrated flux densities at $60~\mu$ m and $100~\mu$ m, corrected for extinction.
Table 2: Overview of the [C I], CO, and ¹³CO data of M 83 and M 51. $\theta _{\rm b}$ is the telescope half power beamwidth. All spectra are scaled to main beam brightness temperatures, $T_{\rm mb}=T_{\rm A}^*/\eta _{\rm {mb}}$ .
Table 3: FIR continuum and line intensities in units of 10^-6 erg s^-1 cm^-2 sr^-1. The absolute calibration error is assumed to be 15% (Gry et al. 2003).
Table 4: Integrated intensities in K km s^-1 (all columns but Cols. 1, 2 and 4) at the resolutions used for the spectra in Figs. 1, 2. Column 2 gives galacto-centric distances $R_{\rm gal}$ in kpc. The calibration error is estimated to be $\sim$ $15\%$ . (The observed [C I] intensities at the center positions agree within 20% with previous data presented in Gerin & Phillips 2000; and Petitpas & Wilson 1998.) Column 4 lists [C I] luminosities in K km s^-1 kpc² in brackets, i.e. the intensities integrated over the 10'' JCMT beam.
Table 5: Line ratios of integrated intensities in K km s^-1. The $1\sigma$ errors are $\sim$ $21\%$ . The CO 3-2/1-0 ratio was added to allow an easier comparison with the literature. To compare all data at a common resolution of 80'', we scaled the [C I] and ¹³CO data, for which maps are not available, using the beam filling factors $\Phi _{\rm B}^{80/10}$ and $\Phi _{\rm B}^{80/21}$ . The factor $\Phi _{\rm B}^{80/10}$ for [C I] and ¹³CO 2-1 data was derived from the ratio of ¹²CO 2-1 integrated intensities at 80'' and at 10'' resolution. Likeweise, the factor $\Phi _{\rm B}^{80/21}$ for ¹³CO 1-0 data was derived from CO 1-0.
Table 6: Results of the escape probability analysis using the four observed line ratios ¹²CO 3-2/2-1, ¹²CO 2-1/1-0, ¹²CO/¹³CO 1-0, and 2-1. N(CO) is the total CO column density per 80'' beam. M is the total mass integrated over the beam and assuming an abundance ratio of [CO]/[H₂] = $8.5\times 10^{-5}$ (Frerking et al. 1982). $n_{\rm av}$ is the average density assuming that emission stems from a sphere with beam diameter.
Table 7: Physical parameters at the observed positions M 83 and M 51, derived from fitting the observed intensity ratios to PDR models of Kaufman et al. (1999). Column (2) gives the galacto-centric distance. Columns (3) and (4) list the fitted local densities and FUV fields together with the corresponding surface temperature (Col. (5)) and the minimum chi squared (Col. (6)). The filling factor $\phi _{\rm UV}=G_{0,\rm obs}/G_0$ reflects the ratio of TIR $_{\rm c}$ to the best fitting FUV field G₀. $\phi _{\rm A}^{\rm CI}$ is the area filling factor of the [C I] emitting regions, i.e. the ratio of observed [C I] intensity vs. that of the best fit model, corrected for beam and velocity filling (see text).
Table 8: FIR line ratios after correcting the observed [C II] intensities for emission from the ionized medium. We study two cases: the emission of [C II] from the ionized medium originates entirely a) from the diffuse medium, and b), that the emission arises entirely from dense H II regions. Also shown is the intensity ratio $\epsilon$ of the two major cooling lines of PDRs ([O I](63)+[C II] $_{\rm PDR}$ ) vs. the observed TIR continuum.