Zwicky Transient Facility and Globular Clusters: The Period-Luminosity and Period-Wesenheit Relations for SX Phoenicis Variables in the gri-Band

Abstract

SX Phoenicis (SXP) variables are short period pulsating stars that exhibit a period-luminosity (PL) relation. We derived the gri-band PL and extinction-free period-Wesenheit (PW) relations, as well as the period-color (PC) and reddening-free period-Q-index (PQ) relations for 47 SXP stars in located in 21 globular clusters using the optical light curves taken from Zwicky Transient Facility (ZTF). These empirically relations were derived for the first time in the gri filters except for the g-band PL relation. We used our gi band PL and PW relations to derive a distance modulus to Crater II dwarf spheroidal which hosts one SXP variable. Assuming that the fundamental and first-overtone pulsation mode for the SXP variable in Crater II, we found distance moduli of $20.03\pm 0.23$ mag and $20.37\pm 0.24$ mag, respectively, using the PW relation, where the latter is in excellent agreement with independent RR Lyrae based distance to Crater II dwarf galaxy.

12 pages, 1 Table and 10 Figures; AJ accepted

References in corpus (21)

• Array Programming with NumPy
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• The Zwicky Transient Facility: System Overview, Performance, and First Results
• The Zwicky Transient Facility: Data Processing, Products, and Archive
• The Zwicky Transient Facility: Science Objectives
• Accurate distances to Galactic globular clusters through a combination of Gaia EDR3, HST and literature data
• The Zwicky Transient Facility: Observing System
• Variable stars in the Fornax dSph Galaxy. II. Pulsating stars below the horizontal branch
• The unblinking eye on the sky
• On the Variation of Fourier Parameters for Galactic and LMC Cepheids at Optical, Near-Infrared and Mid-Infrared Wavelengths
• FORS2/VLT survey of Milky Way globular clusters I. Description of the method for derivation of metal abundances in the optical and application to NGC 6528, NGC 6553, M 71, NGC 6558, NGC 6426 and Terzan 8
• A DECam View of the Diffuse Dwarf Galaxy Crater II: Variable Stars
• A new study of the variable star population in the Hercules globular cluster (M13; NGC 6205)
• Revisiting the variable star population in NGC~6229 and the structure of the Horizontal Branch
• Zwicky Transient Facility and Globular Clusters: The Period-Luminosity and Period-Wesenheit Relations for Type II Cepheids
• The globular cluster M10: Reassessment of stellar membership, distance and age using its variable and HB stars
• A new photometric study of M14 (NGC 6402): An interpretation of the Horizontal Branch and beyond
• A segmented period-luminosity relation for nearby extragalactic $\delta$ Scuti stars
• VR CCD photometry of variable stars in globular cluster NGC 4147
• New SX Phe variables in the globular cluster NGC 288
• A new visit to the variable stars in M56 and its colour magnitude diagram structure