Radial Pulsations in Polaris: A Secondary Science Application of Cherenkov Telescopes via Intensity Interferometry

TL;DR

This paper explores using Cherenkov telescopes during moonlit nights for intensity interferometry to measure stellar parameters of pulsating stars like Polaris, enhancing optical astronomy capabilities.

Contribution

It demonstrates the feasibility of employing existing Cherenkov telescopes for high-resolution stellar measurements through simulations of intensity interferometry.

Findings

Simulations show potential for stellar parameter estimation using Cherenkov telescopes.

Single-telescope configurations can generate multiple baselines for better coverage.

Cherenkov telescopes can be used for optical astronomy during moonlit nights.

Abstract

Ground-based Cherenkov telescopes, although typically inoperative during moonlit nights for gamma-ray observations, offer a valuable opportunity for secondary scientific applications through Intensity Interferometry (II). Recent developments and observations suggest that implementing II instrumentation on existing Imaging Atmospheric Cherenkov Telescopes (IACTs) or the Cherenkov Telescope Array (CTA) can significantly advance optical stellar measurements. Motivated by the resurgence of II efforts over the past two decades, this work presents simulations demonstrating the estimation of stellar parameters for a radially pulsating star, such as Polaris, using either a single telescope or multiple telescopes. For single-telescope simulations, we assume that the photon pixels in the camera are mapped onto four distinct regions of the aperture, generating multiple baselines and enabling enhanced observational plane coverage. These results highlight the potential of Cherenkov telescopes in India for high-resolution optical astronomy during otherwise inoperative periods and offer promising insights into the characterization of bright stellar objects with unprecedented precision.