The VVV survey: Long-period variable stars
نویسندگان
چکیده
Context. Long-period variable stars (LPVs) are pulsating red giants, primarily in the asymptotic giant branch phase, and they include both Miras semi-regular variables (SRVs). Their period-age period-luminosity relations enable us to trace different stellar populations, as intrinsically very bright cover a wide range distances ages. Aims. The purpose of this study is establish census LPV region close Galactic center, using six-year database Vista Variables Vía Láctea (VVV) ESO Public Survey, well describe methodology that was employed search for characterize LPVs VVV data. Near-IR surveys such provide unique opportunity probe high-extinction innermost regions Milky Way. detection analysis could with an excellent properties Way far behind its bulge. Methods. We used point-spread function photometry all available K s -band images ten tiles, covering 16.4 deg 2 total, overlapping fields observed course Optical Gravitational Lensing Experiment (OGLE)-III survey. designed method select candidates, we known from OGLE-III other literature test our approach. reduced χ statistic, along flux-independent index (fi) , were analysis. Lomb-Scargle period method, Fourier analysis, template fitting, visual inspection then performed refine sample included catalog. Results. A final 130 Mira which 129 new discoveries, thus obtained, periods between about 80 1400 days. Moreover, 1013 candidates also presented, whose however not sufficiently constrained by fraction latter may eventually turn out be SRVs. Ages measured these based on reassessment literature. catalog 18 satisfying requirements serve reliable distance indicators saturated images. accordingly derived discussed. number objects seemingly placed Way’s bulge detected.
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ژورنال
عنوان ژورنال: Astronomy and Astrophysics
سال: 2022
ISSN: ['0004-6361', '1432-0746']
DOI: https://doi.org/10.1051/0004-6361/202141805