Star-forming regions of the Aquila rift cloud complex. I. NH3 tracers of
  dense molecular cores
  (Abridged) Aims. In the present part of our survey we search for ammonia
emitters in the Aquila rift complex which trace the densest regions of
molecular clouds. Methods. From a CO survey carried out with the Delingha 14-m
telescope we selected ~150 targets for observations in other molecular lines.
Here we describe the mapping observations in the NH3(1,1) and (2,2) inversion
lines of the first 49 sources performed with the Effelsberg 100-m telescope.
Results. The NH3(1,1) and (2,2) emission lines are detected in 12 and 7
sources, respectively. Among the newly discovered NH3 sources, our sample
includes the following well-known clouds: the starless core L694-2, the Serpens
cloud Cluster B, the Serpens dark cloud L572, the filamentary dark cloud L673,
the isolated protostellar source B335, and the complex star-forming region
Serpens South. Angular sizes between 40" and 80" (~0.04-0.08 pc) are observed
for compact starless cores but as large as 9' (~0.5 pc) for filamentary dark
clouds. The measured kinetic temperatures of the clouds lie between 9K and 18K.
From NH3 excitation temperatures of 3-8K we determine H2 densities with typical
values of ~(0.4-4) 10^4 cm^-3. The masses of the mapped cores range between
~0.05 and ~0.5M_solar. The relative ammonia abundance, X= [NH3]/[H2], varies
from 10^-7 to 5 10^-7 with the mean <X> = (2.7+/-0.6) 10^-7 (estimated from
spatially resolved cores assuming the filling factor eta = 1). In two clouds,
we observe kinematically split NH3 profiles separated by ~1 km/s. The splitting
is most likely due to bipolar molecular outflows for one of which we determine
an acceleration of <~ 0.03 km/s/yr. A starless core with significant rotational
energy is found to have a higher kinetic temperature than the other ones which
is probably caused by magnetic energy dissipation.
