P-band

P-band (230-470 MHz) is available for shared-risk proposals in 2013b.

The new EVLA Lowband receiver system consists of two bands, P: (230-470 MHz) and 4: (54-86 MHz).  Lowband is in the final stages of construction and commissioning has begun. The 4-band part of the system is not ready for open observing yet but P-band is ready for simple, shared-risk continuum projects.  We expect at least 20 antennas to be working at P-band during 2013b. The Lowband system is mounted near the prime focus and, unlike the rest of the VLA bands, uses linear polarization. The wide-band system is significantly more sensitive than the old VLA P-band, due to a lower system temperature and the use of the WIDAR correlator.  We are not yet ready to provide polarization calibration but the system works adequately for simple continuum observations of unpolarized sources. For now the default path for calibration uses AIPS; however, for most projects, the imaging is best done in CASA using its wideband clean algorithm with nterms=2. Calibrated uv data can be ported from AIPS to CASA.