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arXiv · 2112.04597

H-band light curves of Milky Way Cepheids via Difference Imaging

Tarini Konchady·Ryan J. Oelkers·David O. Jones·Wenlong Yuan·Lucas M. Macri·Erik R. Peterson·Adam G. Riess
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Abstract

We present H-band light curves of Milky Way Classical Cepheids observed as part of the DEHVILS survey with the Wide-Field Infrared Camera on the United Kingdom InfraRed Telescope. Due to the crowded nature of these fields caused by defocusing the Camera, we performed difference-imaging photometry by modifying a pipeline originally developed to analyze images from the Transiting Exoplanet Survey Satellite. We achieved a photometric precision in line with expectations from photon statistics, reaching 0.01 mag for 8 <= H <= 11 mag. We used the resulting Cepheid light curves to derive corrections to "mean light" for random-phase Hubble Space Telescope observations in F160W. We find good agreement with previous phase corrections based on VI light curves from the literature, with a mean difference of -1 +/- 6 millimag.

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Tarini Konchady, Ryan J. Oelkers, David O. Jones, Wenlong Yuan, Lucas M. Macri, Erik R. Peterson, Adam G. Riess. 2021-12-08. H-band light curves of Milky Way Cepheids via Difference Imaging. https://doi.org/10.3847/1538-4365/ac41d3

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