English

Closure invariants for polarised radio interferometric observations: a graph theoretical approach

Instrumentation and Methods for Astrophysics 2024-07-02 v1

Abstract

Aperture synthesis observations with full polarisation have long been used to study the magnetic fields of synchrotron emitting sources. Recently proposed closure invariants give us a powerful method for extracting information from measured visibilities which are corrupted by antenna and polarisation dependent gains. In this paper, a formalism developed earlier for complete graphs (where all visibilities are available) is extended to incomplete graphs. The formalism provides a complete and independent set of closure invariants from the measured visibilities in a general situation where not all visibilities are available. We then show in a simulated, quasi-realistic case that the invariants developed here contain usable information even in the presence of noise.

Keywords

Cite

@article{arxiv.2407.00583,
  title  = {Closure invariants for polarised radio interferometric observations: a graph theoretical approach},
  author = {Vinay Kumar and Rajaram Nityananda and Joseph Samuel},
  journal= {arXiv preprint arXiv:2407.00583},
  year   = {2024}
}

Comments

4 pages, 4 figures