We report ^ { 12 } CO ( J = 3–2 ) observations of 15 nearby elliptical galaxies carried out with the ASTE telescope .
Thirteen were selected without regard to the presence of other tracers of cold interstellar matter .
CO emission was detected from three of the galaxies , two of which are undetected by IRAS at 100 microns , suggesting that cold ISM may be present in more ellipticals than previously thought .
The molecular gas masses range from 2.2 \times 10 ^ { 6 } to 4.3 \times 10 ^ { 8 } M _ { \odot } .
The ratio of the CO ( 3–2 ) and ( 1–0 ) lines , R _ { 31 } , has a lower value for elliptical galaxies than for spiral galaxies except for NGC 855 , for which the value is close to the mean for spirals .
The molecular gas in NGC 855 has a mean density in the range 300 – 1000 cm ^ { -3 } adopting a temperature range of 15 – 100 K .