相关论文: AGB Variables and the Mira Period-Luminosity Relat…
Stellar evolution theory predicts that asymptotic giant branch stars undergo a series of short thermal pulses that significantly change their luminosity and mass on timescales of hundreds to thousands of years. Secular changes in these…
The Galactic bulge at latitude $4<|b|$(deg.)$<10$ was claimed to show an X-shape, which means that stellar density distributions along the line of sight have a double peak. However, this double peak is only observed with the red-clump…
We use theoretical models to establish a tight relationship for the absolute magnitudes of RR Lyrae stars as a function of their periods and Stroemgren pseudo-color c_0 = (u-v)_0 - (v-b)_0. Applying this to RR Lyr, and comparing the result…
Empirical and theoretical studies have demonstrated that the periods of Mira variable stars are related to their ages. This, together with their brightness in the infrared, makes them powerful probes of the formation and evolution of…
We present period-luminosity relations for more than 23,000 red giants in the Large Magellanic Cloud observed by the OGLE-II microlensing project. The OGLE period values were combined with the 2MASS single-epoch JHK photometric data. For…
We measure the zero point of the Stanek (1996) extinction map by comparing the observed (V-K) colors of 20 RR Lyrae stars (type ab) found in the MACHO survey with their intrinsic (V-K)_0 colors as a function of period as determined from…
Period-luminosity relations (PLRs) of type II Cepheids (T2Cs) in the Small Magellanic Cloud are derived based on OGLE-III, IRSF/SIRIUS and other data, and these are compared with results for the Large Magellanic Cloud and Galactic globular…
RR Lyrae stars are one of the primary distance indicators for old stellar populations such as globular clusters, dwarf galaxies and galaxies. Typically, fundamental-mode RR Lyr stars are used for distance measurements, and their accuracy is…
Context: Miras are long-period variables thought to be in the asymptotic giant branch (AGB) phase of evolution. In about one percent of known Miras, the pulsation period is changing. It has been speculated that this changing period is the…
Classical variables like RR Lyrae, classical and Type-II Cepheids and Mira variables all follow period-luminosity relations that make them interesting as distance indicators. Especially the RR Lyrae and delta Cepheids are crucial in…
Observations from the Heliospheric Imagers (HI-1) on both the STEREO spacecraft have been analysed to search for very long period large amplitude stellar variability, finding 6 new candidates. A total of 85 objects, mostly previously known…
Based on 14 Miras located in 7 globular clusters, we derived the first gr-band period-luminosity (PL) at maximum light for the large-amplitude Mira variables using the multi-year light-curve data collected from the Zwicky Transient Facility…
Recently obtained kinematic data has shown that the Large Magellanic Cloud (LMC) possesses an old stellar halo. In order to further characterize the properties of this halo, parametric King models are fit to the surface density of RR Lyrae…
The average of 14 recent measurements of the distance to the Large Magellanic Cloud (LMC) implies a true modulus of 18.50 +- 0.02 mag, and demonstrates a trend in the past 2 years of convergence toward a standard value. The distance…
Using time-resolved, mid-infrared data from WISE and geometric parallaxes from HST for four Galactic RR Lyrae variables, we derive the following Population II Period-Luminosity (PL) relations for the WISE [W1], [W2] and [W3] bands at 3.4,…
We have examined the period-luminosity (P-L) relation for delta Scuti stars using Gaia DR2 parallaxes. We included 228 stars from the catalogue of Rodriguez et al. (2000), as well as 1124 stars observed in the four-year Kepler mission. For…
We present time-series observations of Population \rom{2} Cepheids in the Large Magellanic Cloud at near-infrared ($JHK_s$) wavelengths. Our sample consists of 81 variables with accurate periods and optical ($VI$) magnitudes from the OGLE…
We present the catalog of RR Lyrae stars discovered in a 4.5 square degrees area in the central parts of the Large Magellanic Cloud (LMC). Presented sample contains 7612 objects, including 5455 fundamental mode pulsators (RRab), 1655…
We present a systematic analysis to determine and improve the pulsation periods of 1637 known long-period Mira variables in M33 using $gri$-band light curves spanning $\sim18$~years from several surveys, including M33 variability survey,…
In this paper, we analyze period color and amplitude color relations at minimum, mean and maximum $V$ band light for 6391 RRab stars in the Large Magellanic Cloud obtained by the MACHO project. Specifically, we find that color and amplitude…