We present the first interferometric study of the molecular gas in the metal–poor dwarf starburst galaxy NGC 4214 .
Our map of the ^ { 12 } CO ( 1–0 ) emission , obtained at the OVRO millimeter array , reveals an unexpected structural wealth .
We detected three regions of molecular emission in the north–west ( NW ) , south–east ( SE ) and centre of NGC 4214 which are in very different and distinct evolutionary stages ( total molecular mass : \sim 5.1 \times 10 ^ { 6 } M _ { \odot } ) .
These differences are apparent most dramatically when the CO morphologies are compared to optical ground based and HST imaging : massive star formation has not started yet in the NW region ; the well–known starburst in the centre is the most evolved and star formation in the SE complex started more recently .
We derive a star formation efficiency of \sim 8 \% for the SE complex .
Using high–resolution VLA observations of neutral hydrogen ( H i ) and our CO data we generated a total gas column density map for NGC 4214 ( H i + H _ { 2 } ) .
No clear correlation is seen between the peaks of H i , CO and the sites of ongoing star formation .
This emphasizes the irregular nature of dwarf galaxies .
The H i and CO velocities agree well , so do the H \alpha velocities .
In total , we cataloged 14 molecular clumps in NGC 4214 .
Our results from a virial mass analysis are compatible with a Galactic CO-to-H _ { 2 } conversion factor for NGC 4214 ( lower than what is usually found in metal–poor dwarf galaxies ) .