Kavli Affiliate: Wendy L. Freedman
| First 5 Authors: Mahdi Abdollahi, Mahdi Abdollahi, , ,
| Summary:
The Period-Luminosity (PL) relation is usually derived using time-averaged
magnitudes, which require multiple-epoch observations to determine periods and
adequately sample the light curves. Although single-epoch observations are more
practical and require significantly less observational effort, they inherently
introduce greater photometric scatter, leading to an increased dispersion in
the derived Period-Luminosity relations. In this paper, we explore, in detail,
a method that transforms single random-phase data to their mean-light values,
using information obtained in other bands for the same Cepheid. This approach
enables the accurate re-construction of mean-light PL relations for wavelengths
observed with space-based facilities, for instance, where the number of epochs
per star makes simple averaging or template fitting less than optimal, with the
latter requiring very high-precision periods for predictive phasing. While
applying this technique across multiple bands, from optical to mid-IR, we focus
particularly on widely separated bands covering the mid-IR to the optical. We
showcase this method using the J band (as being observed by JWST) as the
random-phase component. Our results show that this correction reduces the
scatter of the PL relation in the J band by a factor of approximately
$0.7times$, equivalent to increasing the number of random-phase observations
by a factor of 10, needed to obtain the same increase in precision as delivered
here.
| Search Query: ArXiv Query: search_query=au:”Wendy L. Freedman”&id_list=&start=0&max_results=3