Low Frequency Observing (L, S, C)

Current->Revised OSS Guidelines

• Sensitivity
  • L band: 420 (RMS confusion level: 89)
  • S band: 370 (RMS confusion level: 14)
  • C band: 310 (RMS confusion level: 2.3)

• EVLA Frequency Bands and Tunability
  • No special notes

• Calibration and Flux Density Scale
  • LOOK AT THE NVSS
  • Accurate flux densities can be obtained by observing one of 3C286, 3C147, 3C48 or 3C138 during the observing run. Not all of these are suitable for every observing band and configuration – consult the VLA Calibrator Manual for advice. Over the last several years, we have implemented accurate source models directly in AIPS and CASA for much improved calibration of the amplitude scales. Models are available for 3C48, 3C138, 3C147, and 3C286 for L, C, X, Ku, K, and Q bands. At Ka band either of the K or Q band models works reasonably well.

Note: Must update OSS Flux densities of Standard Calibrators; need S band fluxes.

• General Guidelines for Gain Calibration
  • If your target object has sufficient flux density to permit phase self-calibration, there is no need to calibrate more than once hourly at low frequencies (L/S/C bands) or 15 minutes at high frequencies (K/Ka/Q bands) in order to track pointing or other effects that might influence the amplitude scale.

Detailed Guidelines

Observing Preparation Recommendations

Scheduling

Calibration Strategy

Known RFI

Calibrator Catalog and Selection

Monitoring Observations

Post-processing Guidelines