The Australia Telescope Compact Array ( ATCA ) has been used to image class I methanol masers at 9.9 , 25 ( a series from J=2 to J=9 ) , 84 , 95 and 104 GHz located in the vicinity of IRAS 16547-4247 ( G343.12-0.06 ) , a luminous young stellar object known to harbour a radio jet .
The detected maser emission consists of a cluster of 6 spots spread over an area of 30″ .
Five spots were detected in only the 84- and 95-GHz transitions ( for two spots the 84-GHz detection is marginal ) , while the sixth spot shows activity in all 12 observed transitions .
We report the first interferometric observations of the rare 9.9- and 104-GHz masers .
It is shown that the spectra contain a very narrow spike ( < 0.03 km s ^ { -1 } ) and the brightness temperature in these two transitions exceeds 5.3 \times 10 ^ { 7 } and 2.0 \times 10 ^ { 4 } K , respectively .
The three most southern maser spots show a clear association with the shocked gas traced by the H _ { 2 } 2.12 \mu m emission associated with the radio jet and their velocities are close to that of the molecular core within which the jet is embedded .
This fact supports the idea that the class I masers reside in the interface regions of outflows .
Comparison with OH masers and infrared data reveals a potential discrepancy in the expected evolutionary state .
The presence of the OH masers usually means that the source is evolved , but the infrared data suggest otherwise .
The lack of any class II methanol maser emission at 6.7 GHz in the source raises an additional question , is this source too young or too old to have a 6.7 GHz maser ?
We argue that both cases are possible and suggest that the evolutionary stage where the class I masers are active , may last longer and start earlier than when the class II masers are active .
However , it is currently not possible to reveal the exact evolutionary status of IRAS 16547-4247 .