A Cluster of Compact Radio Sources in W40
  We present deep 3.6 cm radio continuum observations of the HII region W40
obtained using the Very Large Array in its A and B configurations. We detect a
total of 20 compact radio sources in a region of 4 x 4 arcmin, with 11 of them
concentrated in a band with 30 arcsec of extent. We also present JHK photometry
of the W40 cluster taken with the QUIRC instrument on the University of Hawaii
2.2 meter telescope. These data reveal that 15 of the 20 VLA sources have
infrared counterparts, and 10 show radio variability with periods less than 20
days. Based on these combined radio and IR data, we propose that 8 of the radio
sources are candidate ultracompact HII regions, 7 are likely to be young
stellar objects, and 2 may be shocked interstellar gas.
