Christer Watson edited Analysis.tex  over 9 years ago

Commit id: 4a2fa362198c76ed98e178d1605181c066852c7f

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\begin{equation}  B_{mod} =B_0 \frac{h^2\nu^{3+\beta}}{c^3}\frac{1}{e^{\frac{h\nu}{kT}}-1}  \end{equation}  where $\beta$ is assumed to be 2. B$_0$ and T were taken as free parameters and a Levenberg–Marquardt algorithm was used to find the best-fit.  The total column density is then: calculated using:  \begin{equation}  N_{tot} = \frac{I}{B_\nu \mu m_H \kappa R_d}\\  B_\nu = \frac{2 h \nu^3}{c^2 (e^\frac{h \nu}{kT}-1)}\\  I = 1.085\times 10^{-18} 10^4  B_{mod}(860 GHz)\left(\frac{18.6"}{\theta}\right)^2\\ \kappa = \kappa_{1.3mm} \left(\frac{\lambda}{1.3mm}\right)^{-\beta}\\  \end{equation}  where we have made the following assumptions: $\kappa_{1.3mm}$ = 0.11 $\frac{m^2}{kg}$, appropriate for ice-covered dust grains from OH94, $\theta$=15.0", the beamsize of the GBT at 49 GHz, the mean molecular weight $\mu$ = 2.3 and mass to dust ratio $R_d$ = 100.