2001ApJ...548..253O

We present a coarsely sampled map of the region |l|≤2°, |b|≤0°.1 in the 492 GHz (³P₁⟶³P₀) fine-structure transition of neutral carbon, observed with the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO). The distribution of [C I] emission is similar on the large scale to that of CO J=1⟶0. On average, the ratio of the integrated intensities, I_[CI]_/I¹²CO_, is higher in the Galactic disk than in the Galactic center region. This result is accounted for by the absorption of ¹²CO within the clouds located in the outer Galactic disk. The ratio I_[CI]_/I¹²CO_ is surprisingly uniform over the variety of environments near the Galactic center. On average, [C I] is optically thin [or as optically thin as ¹³CO (J=1⟶0)], even in the dense molecular clouds of the Galactic center region.