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Related papers: Do Miras show the long secondary periods?

200 papers

We have used systematic, sustained visual observations from the AAVSO International Database, and the AAVSO time-series analysis package VSTAR to study the unexplained "long secondary periods" (LSPs) in 27 pulsating red giants. In our…

Solar and Stellar Astrophysics · Physics 2016-07-25 John R. Percy , Emily Deibert

We present a study of OGLE light curves of red giant stars exhibiting long secondary periods (LSPs) - an enigmatic phenomenon commonly observed in stars on the upper red giant branch and asymptotic giant branch. We show that the light…

Solar and Stellar Astrophysics · Physics 2015-06-19 I. Soszynski , A. Udalski

The origin of long secondary periods (LSPs) in red giant variables is unknown. We investigate whether stellar pulsations in red giants can explain the properties of the LSP variability. VIJHKs light curves obtained by OGLE and the…

Solar and Stellar Astrophysics · Physics 2020-01-08 Masaki Takayama , Yoshifusa Ita

Mira variables share essential characteristics: High visual amplitude, periods of hundreds of days, red colors (spectral types M, S, and C), and the presence of emission lines at some phases. They are fundamental mode pulsators, with…

Solar and Stellar Astrophysics · Physics 2012-07-18 Lee Anne Willson , Massimo Marengo

We comprehensively study the variability of Miras in the Large Magellanic Cloud (LMC) by simultaneous analysing light curves in 14 bands in the range of 0.5$-$24 microns. We model over 20-years-long, high cadence $I$-band light curves…

We have analysed publicly available MACHO observations of 6833 variable stars in the Large Magellanic Cloud, classified as eclipsing binaries. After finding that a significant fraction of the sample was misclassified, we redetermined…

Astrophysics · Physics 2009-11-11 A. Derekas , L. L. Kiss , T. R. Bedding

We analyze the distribution of semiregular variables and Mira stars in the period-luminosity plane. Our sample consists of 6169 oxygen-rich long-period variables in the Large Magellanic Cloud included in the OGLE-III Catalog of Variable…

Solar and Stellar Astrophysics · Physics 2015-06-12 I. Soszynski , P. R. Wood

We present Period-Luminosity and Period-Luminosity-Color relations at maximum-light for Mira variables in the Magellanic Clouds using time-series data from the Optical Gravitational Lensing Experiment (OGLE-III) and {\it Gaia} data release…

We study the near-infrared properties of 690 Mira candidates in the central region of the Large Magellanic Cloud, based on time-series observations at JHKs. We use densely-sampled I-band observations from the OGLE project to generate…

Solar and Stellar Astrophysics · Physics 2017-09-27 Wenlong Yuan , Lucas M. Macri , Shiyuan He , Jianhua Z. Huang , Shashi M. Kanbur , Chow-Choong Ngeow

[abbreviated] Long Secondary Periods (LSPs) are observed in about one third of pulsating red giants yet remain unexplained. Four key observational constraints anchor the discussion: (i) a roughly 30 percent occurrence rate in semi-regular…

Solar and Stellar Astrophysics · Physics 2025-11-26 Leen Decin , Owen Vermeulen , Mats Esseldeurs , Florian Driessen , Camille Landri , Davide Dionese , Lionel Siess , Dorota M. Skowron

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…

Solar and Stellar Astrophysics · Physics 2015-06-05 K. T. Wraight , D. Bewsher , Glenn J. White , W. Nowotny , A. J. Norton , C. Paladini

The origin of the long secondary periods (LSPs) in red variables remains a mystery up to now, although there exist many models. The light curves of some LSPs stars mimic an eclipsing binary with a pulsating red giant component. To test this…

Solar and Stellar Astrophysics · Physics 2015-05-18 J. D. Nie , X. B. Zhang , B. W. Jiang

This article presents the study of the light-curves extracted from the MACHO database of a sample of stars observed by the ISO in the SMC. These stars belong to the ISO-Mini-Survey catalogue of the Magellanic Clouds (ISO-MCMS, Loup et al.…

Motivated by the detection of a recent outburst of the massive luminous blue variable LMC-R71, which reached an absolute magnitude M_V = -9.3 mag, we undertook a systematic study of the optical variability of 1268 massive stars in the Large…

Solar and Stellar Astrophysics · Physics 2015-03-13 D. M. Szczygiel , K. Z. Stanek , A. Z. Bonanos , G. Pojmanski , B. Pilecki , J. L. Prieto

Some Miras -- long-period variables in late evolutionary stages -- have meandering pulsation periods and light curve asymmetries, the causes of which are still unclear. We aim to understand better the origin of these phenomena by…

Solar and Stellar Astrophysics · Physics 2023-04-19 P. Merchan-Benitez , S. Uttenthaler , M. Jurado-Vargas

Long secondary periods (LSPs), observed in a third of pulsating red giant and supergiant stars, are the only unexplained type of large-amplitude stellar variability known at this time. Numerous authors have explored various scenarios for…

Solar and Stellar Astrophysics · Physics 2022-04-07 I. Soszyński

At least a third of red giants show a long secondary period (LSP), 5 to 10 times longer than the pulsation period. There is strong evidence that the LSP is caused by eclipses of the red giant by a dust-enshrouded low-mass companion. We have…

Solar and Stellar Astrophysics · Physics 2025-03-05 John Percy , Melanie Szpigiel

Context. The EROS-2 survey has produced a database of millions of time series from stars monitored for more than six years, allowing to classify some of their sources into different variable star types. Among these, Long Period Variables…

Solar and Stellar Astrophysics · Physics 2015-05-30 M. Spano , N. Mowlavi , L. Eyer , G. Burki , J. -B. Marquette , I. Lecoeur-Taïbi , P. Tisserand

We have used AAVSO visual and photoelectric V data, and the AAVSO time-series package VSTAR and the Lomb-Scargle time-series algorithm to determine improved pulsation periods, "long secondary periods" (LSPs). and their amplitudes in 51…

Solar and Stellar Astrophysics · Physics 2016-11-11 John R. Percy , Henry Leung

The third part of the OGLE-III Catalog of Variable Stars comprises 24906 RR Lyr stars in the Large Magellanic Cloud (LMC). This sample consists of 17693 fundamental-mode (RRab), 4958 first-overtone (RRc), 986 double-mode (RRd) and 1269…

Solar and Stellar Astrophysics · Physics 2009-04-03 I. Soszynski , A. Udalski , M. K. Szymanski , M. Kubiak , G. Pietrzynski , L. Wyrzykowski , O. Szewczyk , K. Ulaczyk , R. Poleski