Results 91 to 100 of about 577 (218)

OGLE-IV Period–Luminosity Relation of the LMC: An Analysis Using Mean and Median Magnitudes

The Astronomical Journal
The Period–Luminosity (PL) relation for Cepheid variable stars in the LMC is crucial for distance measurements in astronomy. This study analyzes the impact of using the median rather than the mean of the PL relation’s slope and zero-point.
Jaime Muñoz, Alejandro García-Varela, Santiago Henao-Castellanos, Beatriz Sabogal, Luis Felipe Giraldo, Jorge Martínez   +5 more
doaj   +1 more source

A package for the automated classification of periodic variable stars

, 2016
We present a machine learning package for the classification of periodic variable stars. Our package is intended to be general: it can classify any single band optical light curve comprising at least a few tens of observations covering durations from ...
Dae-Won Kim, Coryn A. L. Bailer-Jones
core   +1 more source

Converging on the Cepheid Metallicity Dependence: Implications of Nonstandard Gaia Parallax Recalibration on Distance Measures

The Astrophysical Journal
By comparing Cepheid brightnesses with geometric distance measures including Gaia EDR3 parallaxes, most recent analyses conclude metal-rich Cepheids are brighter, quantified as γ ∼ −0.2 mag dex ^−1 .
Louise Breuval, Gagandeep S. Anand, Richard I. Anderson, Rachael Beaton, Anupam Bhardwaj, Stefano Casertano, Gisella Clementini, Mauricio Cruz Reyes, Giulia De Somma, Martin A. T. Groenewegen, Caroline D. Huang, Pierre Kervella, Saniya Khan, Lucas M. Macri, Marcella Marconi, Javier H. Minniti, Adam G. Riess, Vincenzo Ripepi, Martino Romaniello, Daniel Scolnic, Erasmo Trentin, Piotr Wielgórski, Wenlong Yuan   +22 more
doaj   +1 more source

The OGLE Collection of Variable Stars. Classical Cepheids in the Magellanic System

, 2016
16 pages, 5 ...
Soszynski, I., Udalski, A., Szymanski, M. K., Skowron, D., Pietrzynski, G., Poleski, R., Pietrukowicz, P., Skowron, J., Mroz, P., Kozlowski, S., Wyrzykowski, L., Ulaczyk, K., Pawlak, M.   +12 more
openaire   +2 more sources

Stars Classified as Constant in the General Catalogue of Variable Stars, II

, 1996
Photometric observations have been made of 36 stars classified as CST or CST: in the General Catalogue of Variable Stars. Six of these stars are found to vary and three others were deemed possible variables.
Schmidt, Edward G.
core  

The Cepheid Distance Scale: A Novel Method for Obtaining Mean Magnitudes from Single-epoch Observations

The Astronomical Journal
We present a novel technique for mapping single-phase observations of Cepheids in any given band into their time-averaged values, using strong priors on the known interrelations of the multiwavelength widths of Cepheid period–luminosity (PL) relations ...
Barry F. Madore, Wendy L. Freedman, Kayla Owens   +2 more
doaj   +1 more source

Stellar Variability and Distance Indicators in the Near-infrared in Nearby Galaxies. II. Pulsating Stars in the Carina Dwarf Spheroidal

The Astronomical Journal
We present homogeneous, near-infrared ( JHK _s bands) time-series observations of the classical Carina dwarf spheroidal (dSph) galaxy to determine accurate and precise distances using the pulsating stars as standard candles.
Chow-Choong Ngeow, Anupam Bhardwaj, Prashant Nishad, Susmita Das   +3 more
doaj   +1 more source

Type II Cepheids: period-luminosity-metallicity relations for the Population II distance scale

Frontiers in Astronomy and Space Sciences
Type II Cepheids are a class of pulsating variable stars that play a critical role in our understanding of stellar evolution, distance measurement and tracing the structure and kinematics of old stars in nearby galaxies.
Susmita Das, Susmita Das, Susmita Das, Anupam Bhardwaj, Marcella Marconi   +4 more
doaj   +1 more source

IS POLARIS LEAVING THE CEPHEID INSTABILITY STRIP?

Odessa Astronomical Publications, 2017
Although Polaris is generally regarded as an overtone pulsator that may soon switch to pulsation in the fundamental mode, it is argued that the variable is actually crossing the instability strip for the first time and is in the process of leaving the ...
D. G. Turner
doaj   +1 more source

The nature of the Cepheid T Antliae

, 2003
The variable star T Antliae, sometimes suspected to be a type II pulsator, is demonstrated to be a classical Cepheid in the third crossing of the instability strip.
D. G. Turner, L. N. Berdnikov
core   +1 more source