Phase co-existence in bidimensional passive and active dumbbell systems
  We demonstrate that there is macroscopic co-existence between regions with hexatic order and regions in the liquid/gas phase over a finite interval of packing fractions in active dumbbell systems with repulsive power-law interactions in two dimensions. In the passive limit this interval remains finite, similarly to what has been found in bidimensional systems of hard and soft disks. We did not find discontinuous behaviour upon increasing activity from the passive limit. 
Leticia F. Cugliandolo, Pasquale Digregorio, Giuseppe Gonnella, and   Antonio Suma
cond-mat.stat-mech cond-mat.soft