We have observed the host galaxy of the low redshift , low luminosity GRB 080517 at 105.8 GHz using the IRAM Plateau de Bure interferometer .
We detect an emission line with integrated flux S \Delta \nu = 0.39 \pm 0.05 Jy km s ^ { -1 } – consistent both spatially and in velocity with identification as the J=1-0 rotational transition of carbon monoxide ( CO ) at the host galaxy redshift .
This represents only the third long GRB host galaxy with molecular gas detected in emission .
The inferred molecular gas mass , M _ { \mathrm { H _ { 2 } } } \sim 6.3 \times 10 ^ { 8 } M _ { \odot } , implies a gas consumption timescale of \sim 40 Myr if star formation continues at its current rate .
Similar short timescales appear characteristic of the long GRB population with CO observations to date , suggesting that the gamma-ray burst in these sources occurs towards the end of their star formation episode .