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Related papers: Long-Period Variability in o Ceti

200 papers

Long term monitoring observations with the Hitachi 32-m radio telescope of the 6.7 GHz methanol masers associated with the high mass star-forming region G5.900-0.430 is presented. A period of flux variability at approximately 1260 days, is…

Solar and Stellar Astrophysics · Physics 2023-02-08 Yoshihiro Tanabe , Yoshinori Yonekura , MacLeod C. Gordon

Beta Cephei-type variables are early B-type stars that are characterized by oscillations observable in their optical light curves. At least one Beta Cep-variable also shows periodic variability in X-rays. Here we study the X-ray light…

Solar and Stellar Astrophysics · Physics 2015-04-29 L. M. Oskinova , H. Todt , D. P. Huenemoerder , S. Hubrig , R. Ignace , W. -R. Hamann , L. Balona

The period-luminosity relation of Miras and semiregular variables in the Large Magellanic Cloud and in the Galaxy is used to locate their instability domain in the Hertzsprung-Russell diagram. We take advantage of the considerable width in…

Astrophysics · Physics 2007-05-23 Alfred Gautschy

Massive stars play a significant role in the chemical and dynamical evolution of galaxies. However, much of their variability, particularly during their evolved supergiant stage, is poorly understood. To understand the variability of…

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

The results of 8-year R-band photopolarimetric data of blazar Mrk 421 collected from February 2008 to May 2016 are presented, along with extensive multiwavelength observations covering from radio to TeV $\gamma$-rays around the flares…

The light curve of a blue variable in the MACHO LMC database (FTS ID 78.5979.72) appeared nearly unvarying for ~4 years (quasi-flat segment) but then rapidly changed to become periodic with noisy minima for the remaining 4 years (periodic…

We search a sample of 9,361,613 isolated sources with 13<g<14.5 mag for slowly varying sources. We select sources with brightness changes larger than ~ 0.03 mag/year over 10 years, removing false positives due to, for example, nearby bright…

Solar and Stellar Astrophysics · Physics 2025-01-27 Sydney Petz , Christopher S. Kochanek

In the first spectroscopic campaign for a PG 1716 variable (or long-period pulsating subdwarf B star), we succeeded in detecting velocity variations due to g-mode pulsations at a level of 1.0-1.5 km/s.The observations were obtained during…

We report results of VI time series photometry for the bright globular cluster M5 taken between 2007-2011 using the 0.5-m telescope at Bowling Green State Univ. and the PROMPT #4 telescope at Cerro Tololo. We used DAOPHOT to obtain…

Solar and Stellar Astrophysics · Physics 2013-10-03 Michael Wehrung , Andrew Layden

We present K-band commissioning observations of the Mira star prototype o Cet obtained at the ESO Very Large Telescope Interferometer (VLTI) with the VINCI instrument and two siderostats. The observations were carried out between 2001…

Three fields covering the central part of the globular cluster Omega Cen were surveyed in a search for variable stars. We present V-band light curves for 22 periodic variables: 9 SX~Phe stars, 7 contact binaries, 5 detached or semi-detached…

Astrophysics · Physics 2007-05-23 J. Kaluzny , M. Kubiak , M. Szymanski , A. Udalski , W. Krzeminski , M. Mateo

A search has been carried out for the pulsar J0311+1402, which has a period of $P = 40.9$ s, in the data archive of the Large Phased Array (LPA) radio telescope. When searching using fast folding algorithm (FFA), periodic pulsar radiation…

High Energy Astrophysical Phenomena · Physics 2025-08-12 S. A. Tyul'bashev , G. E. Tyul'basheva , S. A. Andrianov , M. A. Kitaeva

In a photometric variability survey of 131 stars with B < 14 mag, we have found four new Delta Scuti stars. We were sensitive to oscillation amplitudes as low as a few mmag. The detection rate of short-period (P < 0.1 d) pulsating variable…

Astrophysics · Physics 2009-11-07 J. L. Sokoloski , Lars Bildsten , R. Chornock , Alexei V. Filippenko

Spectroscopic measurements of Mira variable stars, as a function of phase, probe the stellar atmospheres and underlying pulsation mechanisms. For example, measuring variations in TiO, VO, and ZrO with phase can be used to help determine…

The goal of this paper is to characterise the light variation properties of Mira variables in the Small Magellanic Cloud. We have investigated a combined optical and near infrared multi-epoch dataset of Mira variables based on our…

In this paper we present results of a short-term optical monitoring of 13 blazars. The objects were monitored mostly in the R-band for a total of ~ 160 hours between 2006 and 2011. We study the nature of the short-term variations and show…

High Energy Astrophysical Phenomena · Physics 2013-11-21 R. Bachev , E. Semkov , A. Strigachev , Alok C. Gupta , Haritma Gaur , B. Mihov , S. Boeva , L. Slavcheva-Mihova

Period-luminosity (PL) sequences of long period variables (LPVs) are commonly interpreted as different pulsation modes, but there is disagreement on the modal assignment. Here, we re-examine the observed PL sequences in the Large Magellanic…

Solar and Stellar Astrophysics · Physics 2017-10-11 Michele Trabucchi , Peter R. Wood , Josefina Montalbán , Paola Marigo , Giada Pastorelli , Léo Girardi

This paper presents light curves and the first systematic characterization of variability of the 106 objects in the Fermi Large Area Telescope (LAT) Bright AGN Sample (LBAS). Weekly light curves obtained during the first 11 months of survey…

High Energy Astrophysical Phenomena · Physics 2015-05-18 A. A. Abdo

Stellar photometric variability offers a novel probe of the interior structure and evolutionary state of stars. Here we present a census of stellar variability on day to decade timescales across the color-magnitude diagram for 73,000 stars…