Seminars and Colloquia

Enhancing Binary Star Resolution with Hanbury Brown and Twiss InterferometryAstrophysics Seminar

by Km Nitu Rai (IISER, Thiruvananthapuram)

Asia/Kolkata
Auditorium

Auditorium

Description

The process of star formation and evolution continues to fascinate astronomers while remaining a complex puzzle. Resolving binary star systems is crucial for advancing our understanding of them, which allows for precise mass measurements. While radio wavelengths have achieved remarkable resolutions, optical wavelengths pose significant challenges due to the need for longer baselines and sensitive apertures. Traditional amplitude interferometry, effective in the visible spectrum, needs help to maintain wavelength coherency over the observational setup. In the 1950s, Robert Hanbury Brown and Richard Q. Twiss observed correlation phenomena in intensity fluctuations, leading to the discovery of the Hanbury-Brown and Twiss (HBT) effect. Intensity Interferometry (II) and Speckle Interferometry, based on the HBT effect, overcome the limitations of amplitude interferometry by measuring the correlation of photon flux rather than wavelength. This approach makes Speckle interferometry less susceptible to issues like atmospheric turbulence. However, II also has fewer issues with mirror optical quality and longer baselines. Imaging Atmospheric Cherenkov Telescopes (IACTs) such as HESS, MAGIC, and VERITAS show promise for implementing II, particularly during moonlit periods. This presentation will explain the HBT effect using a lab experiment and share results from II simulations applied to binary star systems. These simulations accurately estimate key parameters, including star’s radii, limb-darkening coefficients, and orbital characteristics for both close and wide binary systems. This talk aims to provide an engaging understanding of how II resolves binary star systems and enhances our understanding of the stars.

Organized by

Colloquium Committee