The second-brightest star formation complex in the Large Magellanic Cloud , N 11 , was surveyed extensively in the J =1–0 transition of { { } ^ { 12 } CO } .
In this paper we present maps and a catalogue containing the parameters of 29 individual molecular clouds in the complex , although more may be present .
The distribution of molecular gas in the N 11 complex is highly structured .
In the southwestern part of N 11 , molecular clouds occur in a ring or shell surrounding the major OB star association LH 9 .
In the northeastern part , a chain of molecular clouds delineates the rim of one of the so-called supergiant shells in the LMC .
There appears to be very little diffuse molecular gas in between the individual well-defined clouds , especially in the southwestern ring .
Most of the clouds have dimensions only little larger than those of the survey beam , i.e diameters of 25 pc or less .
A subset of the clouds mapped in J = 1 - 0 { { } ^ { 12 } CO } transition was also observed in the J = 2 - 1 { { } ^ { 12 } CO } transition , and in the corresponding transitions of { { } ^ { 13 } CO } .
Clouds mapped in J = 2 - 1 { { } ^ { 12 } CO } with a twice higher angular resolution show further , clear substructure .
The elements of this substructure , however , have dimensions once again comparable to those of the mapping beam .
For a few clouds , sufficient information was available to warrant an attempt at modelling their physical parameters .
They contain fairly warm ( T _ { kin } = 60 - 150 K ) and moderately dense ( n _ { { H _ { 2 } } } = 3000 { cm ^ { -3 } } ) gas .
The northeastern chain of CO clouds , although lacking in diffuse intercloud emission , is characteristic of the more quiescent regions of the LMC , and appears to have been subject to relatively little photo-processing .
The clouds forming part of the southwestern shell or ring , however , are almost devoid of diffuse intercloud emission , and also exhibit other characteristics of an extreme photon-dominated region ( PDR ) .