Visibility sampling, smearing and calibration
Research context
research method · conditional · As of 2026-10-10
An interferometer measures a finite set of Fourier samples, leaving unmeasured sky modes.
Key knowledge
An interferometer measures a finite set of Fourier samples, leaving unmeasured sky modes. Frequency/time averaging smears off-centre sources; non-coplanar baselines need a w-term. Bandpass, complex gains, polarization leakage and position angle require separate calibration.
Conditions and scope
- A deconvolved image depends on weighting and reconstruction assumptions; missing short baselines can remove extended flux.
- Use channel/integration intervals appropriate to field and baseline; old instrument tables are not current observing recommendations.
Sources · 3
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
VLA field-of-view limitations: Bandwidth/time averaging, primary beam and non-coplanar baselines; only stable physical principles used (selected source body inspected). Instrumental polarization calibration: Section 4.4.5: polarization leakage, relative gain and absolute angle; stable physical requirements only (selected source body inspected). Wide-field imaging: Non-coplanar baselines and the w-term (selected source body inspected).
2026-10-10 · Bounded source check of the recorded statement and conditions. This does not certify a unique physical model, reproduce the cited study or replace independent branch review.
Entry details
Permanent link to this entry ↗- Record identity
- research-earth-radio-sampling
- Revision
- research.1
- Structured reference record
- Postgraduate & research reference