Evaluating and Enhancing Candidate Clocking Systems for CHIME/FRB VLBI Outriggers

TL;DR

This paper discusses methods to evaluate and improve candidate clock systems for CHIME/FRB Outriggers, enabling precise VLBI localization of fast radio bursts even without access to highly stable maser standards.

Contribution

It introduces calibration techniques for less stable clocks, ensuring milliarcsecond localization precision in VLBI without requiring maser standards.

Findings

Calibration algorithms improve clock stability for VLBI

Methods enable precise FRB localization without masers

Techniques maintain milliarcsecond accuracy

Abstract

As the Canadian Hydrogen Intensity Mapping Experiment (CHIME) has become the leading instrument for detecting Fast Radio Bursts (FRBs), CHIME/FRB Outriggers will use very-long-baseline interferometry (VLBI) to localize FRBs with milliarcsecond precision. The CHIME site uses a passive hydrogen maser frequency standard in order to minimize localization errors due to clock delay. However, not all outrigger stations will have access to a maser. This report presents techniques used to evaluate clocks for use at outrigger sites without a maser. More importantly, the resulting algorithm provides calibration methods for clocks that do not initially meet the stability requirements for VLBI, thus allowing CHIME/FRB Outriggers to remain true to the goal of having milliarcsecond precision.