We report Atacama Large Millimeter/submillimeter Array ( ALMA ) Band 6 continuum observations of 2000 AU resolution toward four massive molecular clouds in the Central Molecular Zone of the Galaxy .
To study gas fragmentation , we use the dendrogram method to identify cores as traced by the dust continuum emission .
The four clouds exhibit different fragmentation states at the observed resolution despite having similar masses at the cloud scale ( \sim 1–5 pc ) .
Assuming a constant dust temperature of 20 K , we construct core mass functions of the clouds and find a slightly top-heavy shape as compared to the canonical initial mass function , but we note several significant uncertainties that may affect this result .
The characteristic spatial separation between the cores as identified by the minimum spanning tree method , \sim 10 ^ { 4 } AU , and the characteristic core mass , 1–7 M _ { \odot } , are consistent with predictions of thermal Jeans fragmentation .
The three clouds showing fragmentation may be forming OB associations ( stellar mass \sim 10 ^ { 3 } M _ { \odot } ) .
None of the four clouds under investigation seem to be currently able to form massive star clusters like the Arches and the Quintuplet ( \gtrsim 10 ^ { 4 } M _ { \odot } ) , but they may form such clusters by further gas accretion onto the cores .