Primary beam calibration for commensal telescopes utilizing offset optics

IntroductionAccurate primary beam calibration is essential for precise brightness measurements in radio astronomy. The VLA Low-band Ionosphere and Transient Experiment (VLITE) faces challenges in calibration due to the offset Cassegrain optics used in its commensal observing system. This study aims...

詳細記述

書誌詳細
出版年:Frontiers in Astronomy and Space Sciences
主要な著者: Emil Polisensky, Tracy E. Clarke, Simona Giacintucci, Wendy Peters
フォーマット: 論文
言語:英語
出版事項: Frontiers Media S.A. 2024-12-01
主題:
オンライン・アクセス:https://www.frontiersin.org/articles/10.3389/fspas.2024.1497375/full
その他の書誌記述
要約:IntroductionAccurate primary beam calibration is essential for precise brightness measurements in radio astronomy. The VLA Low-band Ionosphere and Transient Experiment (VLITE) faces challenges in calibration due to the offset Cassegrain optics used in its commensal observing system. This study aims to develop a novel calibration method to improve accuracy with no impact on the Very Large Array (VLA) primary science observations.MethodsWe used the apparent brightness of standard candles identified in VLITE’s commensal data to develop 1D and 2D primary beam response models. These models accounted for operational changes and asymmetries caused by the subreflector and were validated against holographic methods and compact source light curves.ResultsThe models achieved calibration accuracy within 3% across the field of view, significantly improving the precision of brightness measurements. The results were consistent with holography-derived solutions and performed reliably under different operational conditions.DiscussionThis improved calibration technique expands VLITE’s capabilities for studying active galactic nuclei, transients, and pulsars. It offers a cost-effective alternative to traditional holographic methods, facilitating broader use in commensal observing systems.
ISSN:2296-987X