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Title: Extra-galactic Distances with Massive Stars: The Role of Stellar Variability in the Case of M33

Abstract

In modern cosmology, determining the Hubble constant (H{sub 0}) using a distance ladder to percent level and comparing with the results from the Planck  satellite can shed light on the nature of dark energy, physics of the neutrino, and curvature of the universe. Thanks to the endeavor of the SH0ES team, the uncertainty of the H{sub 0} has be dramatically reduced, from 10% to 2.4%, and with the promise of even reaching 1% in the near future. In this regard, it is fundamentally important to investigate the systematics. This is best done using other good independent distance indicators. One promising method is the flux-weighted gravity luminosity relation (FGLR) of the blue supergiants (BSGs). As BSGs are the brightest objects in galaxies, they can probe distances up to 10 Mpc with negligible blending effects. While the FGLR method delivered distance is in good agreement with other distance indicators, it has been shown that this method delivers greater distances in the cases of M33 and NGC 55. Here, we investigate whether the M33 distance estimate of FGLR suffers systematics from stellar variability. Using CFHT M33 monitoring data, we found that 9 out of 22 BSGs showed variability during the course of 500 days,more » although with amplitudes as small as 0.05 mag. This suggests that stellar variability plays a negligible role in the FGLR distance determination.« less

Authors:
 [1]
  1. Subaru Telescope, NAOJ, 650 N Aohoku Pl, Hilo, HI 96720 (United States)
Publication Date:
OSTI Identifier:
22663325
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 154; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPARATIVE EVALUATIONS; COSMOLOGY; DISTANCE; GALAXIES; GRAVITATION; INDICATORS; LUMINOSITY; MONITORING; NONLUMINOUS MATTER; PROBES; RED SHIFT; SATELLITES; STAR CLUSTERS; SUPERGIANT STARS; UNIVERSE; VISIBLE RADIATION

Citation Formats

Lee Chien-Hsiu, E-mail: leech@naoj.org. Extra-galactic Distances with Massive Stars: The Role of Stellar Variability in the Case of M33. United States: N. p., 2017. Web. doi:10.3847/1538-3881/AA7FBE.
Lee Chien-Hsiu, E-mail: leech@naoj.org. Extra-galactic Distances with Massive Stars: The Role of Stellar Variability in the Case of M33. United States. doi:10.3847/1538-3881/AA7FBE.
Lee Chien-Hsiu, E-mail: leech@naoj.org. Tue . "Extra-galactic Distances with Massive Stars: The Role of Stellar Variability in the Case of M33". United States. doi:10.3847/1538-3881/AA7FBE.
@article{osti_22663325,
title = {Extra-galactic Distances with Massive Stars: The Role of Stellar Variability in the Case of M33},
author = {Lee Chien-Hsiu, E-mail: leech@naoj.org},
abstractNote = {In modern cosmology, determining the Hubble constant (H{sub 0}) using a distance ladder to percent level and comparing with the results from the Planck  satellite can shed light on the nature of dark energy, physics of the neutrino, and curvature of the universe. Thanks to the endeavor of the SH0ES team, the uncertainty of the H{sub 0} has be dramatically reduced, from 10% to 2.4%, and with the promise of even reaching 1% in the near future. In this regard, it is fundamentally important to investigate the systematics. This is best done using other good independent distance indicators. One promising method is the flux-weighted gravity luminosity relation (FGLR) of the blue supergiants (BSGs). As BSGs are the brightest objects in galaxies, they can probe distances up to 10 Mpc with negligible blending effects. While the FGLR method delivered distance is in good agreement with other distance indicators, it has been shown that this method delivers greater distances in the cases of M33 and NGC 55. Here, we investigate whether the M33 distance estimate of FGLR suffers systematics from stellar variability. Using CFHT M33 monitoring data, we found that 9 out of 22 BSGs showed variability during the course of 500 days, although with amplitudes as small as 0.05 mag. This suggests that stellar variability plays a negligible role in the FGLR distance determination.},
doi = {10.3847/1538-3881/AA7FBE},
journal = {Astronomical Journal (Online)},
number = 2,
volume = 154,
place = {United States},
year = {Tue Aug 01 00:00:00 EDT 2017},
month = {Tue Aug 01 00:00:00 EDT 2017}
}