Abstract Details

Name: Anupam Bhardwaj
Affiliation: Kavli Institute for Astronomy and Astrophysics, China
Conference ID: ASI2020_214
Title : Extragalactic distance scale with pulsating stars
Authors and Co-Authors : Shashi Kanbur (SUNY Oswego, USA), Lucas Macri (Texas A&M, USA), Marina Rejkuba (ESO, Germany), H.P. Singh (Delhi University)
Abstract Type : Oral
Abstract Category : Extragalactic Astronomy
Abstract : Pulsating stars such as Cepheid, RR Lyrae, and Miras are a sensitive probe of both stellar astrophysics and the cosmic distance scale. Cepheid variables, the primary standard candles, have been extensively used to estimate the Hubble constant which parametrizes the expansion rate of the Universe. I will briefly review the current tension in the Hubble constant measurements between the late and early Universe. I will summarize results on Cepheid variables from our near-infrared survey of the Large Magellanic Cloud and the ongoing RR Lyrae observations in the globular clusters at CFHT. Our Cepheid results provided a ten-fold increase in the precision of their Period-Luminosity relations, which resulted in a significant improvement in the calibration of the first-rung of the extragalactic distance ladder. I will also present the maximum light properties of Mira variables and their potential for the distance scale in the LSST era.