Results 21 to 30 of about 179 (144)

Study of the Blazhko Type RRc stars in the Stripe 82 Region Using SDSS and ZTF

The Astronomical Journal, 2023
RR Lyrae stars (RRLs) are pulsating stars, many of which also show a long-term variation called the Blazhko effect which is a modulation of amplitude and phase of the lightcurve.
Vaidehi Varma, József M. Benkő, Chow-Choong Ngeow   +2 more
doaj   +1 more source

On the RR Lyrae Stars in Globulars. V. The Complete Near-infrared (JHK_s) Census of ω Centauri RR Lyrae Variables* [PDF]

The Astronomical Journal, 2018
Abstract We present a new complete near-infrared (NIR, JHK s ) census of RR Lyrae stars (RRLs) in the globular ω Cen (NGC 5139). We collected 15,472 JHK s images with 4–8 m class telescopes over 15 years (2000–2015 ...
V. F. Braga, P. B. Stetson, G. Bono, M. Dall’Ora, I. Ferraro, G. Fiorentino, G. Iannicola, M. Marconi, M. Marengo, A. J. Monson, J. Neeley, S. E. Persson, R. L. Beaton, R. Buonanno, A. Calamida, M. Castellani, E. Di Carlo, M. Fabrizio, W. L. Freedman, L. Inno, B. F. Madore, D. Magurno, E. Marchetti, S. Marinoni, P. Marrese, N. Matsunaga, D. Minniti, M. Monelli, M. Nonino, A. M. Piersimoni, A. Pietrinferni, P. Prada-Moroni, L. Pulone, R. Stellingwerf, E. Tognelli, A. R. Walker, E. Valenti, M. Zoccali   +37 more
openaire   +6 more sources

The Changing Lightcurve of the Double-mode RR Lyrae Variable Star V338 Boo [PDF]

The Astrophysical Journal Letters, 2021
Abstract We present an analysis of the lightcurve extracted from Transiting Exoplanet Survey Satellite (TESS) Full Frame Images (FFIs) of the double-mode RR Lyrae V338 Boo. We find that the fundamental mode pulsation is changing in amplitude across the 54 days of observations.
Kenneth Carrell, Ronald Wilhelm, Faith Olsen, Andrew Tom, Garath Vetters, Anna McElhannon   +5 more
openaire   +2 more sources

The K2 RR Lyrae Survey

EPJ Web of Conferences, 2017
We have initiated a large survey with K2 to observe thousands of RR Lyrae stars along the Ecliptic. The high photometric precision and the 80-90-day continuous coverage will allow us to investigate the light variation of these galactic structure tracer ...
Szabó Róbert, Kolenberg Katrien, Molnár László, Plachy Emese, Klagyivik Péter, Hanyecz Ottó   +5 more
doaj   +1 more source

THE CHEMICAL COMPOSITIONS OF RR LYRAE TYPE C VARIABLE STARS [PDF]

The Astrophysical Journal, 2014
We present a detailed chemical abundance study of eight RR Lyrae variable stars of subclass c (RRc). The target RRc stars chosen for study exhibit "Blazhko-effect" period and amplitude modulations to their pulsational cycles. Data for this study were gathered with the echelle spectrograph of the 100 inch du Pont telescope at Las Campanas Observatory ...
Govea, Jose, Gomez, Thomas, Preston, George W., Sneden, Christopher   +3 more
openaire   +2 more sources

First direct detection of an RR Lyrae star conclusively associated with an intermediate-age cluster

Astronomy & Astrophysics
Context. RR Lyrae stars have long been considered unequivocal tracers of old (>10 Gyr) and metal-poor ([Fe/H]
Mateu Cecilia, Cuevas-Otahola Bolivia, Downes Juan José   +2 more
doaj   +1 more source

Pulsating stars in ω Centauri. Near-IR properties and period-luminosity relations

EPJ Web of Conferences, 2017
ω Centauri (NGC 5139) contains many variable stars of different types, including the pulsating type II Cepheids, RR Lyrae and SX Phoenicis stars. We carried out a deep, wide-field, near-infrared (IR) variability survey of ω Cen, using the VISTA telescope.
Navarrete Camila, Catelan Márcio, Contreras Ramos Rodrigo, Alonso-García Javier, Gran Felipe, Dékány István, Minniti Dante   +6 more
doaj   +1 more source

Progress report on the K2 RR Lyrae survey

EPJ Web of Conferences, 2017
We have initiated a large survey with K2, to observe thousands of RR Lyrae stars along the ecliptic. The high photometric precision and the 70-90-day continuous coverage will allow us to investigate the light variation of these galactic structure tracer ...
Szabó Róbert
doaj   +1 more source

Period distributions of irregularly variable RR Lyrae stars [PDF]

Publications of the Astronomical Society of the Pacific, 1981
The occurrence of irregularly variable RR Lyrae stars in four globular clusters and the Draco dwarf spheroidal galaxy are examined in order to determine their period distributions. Two of the clusters are of Oosterhoff type I, M3 and M5, and two are of Oosterhoff type II, M15 and omega-Cen.
openaire   +1 more source

RR Lyrae binary systems in the Galactic bulge

EPJ Web of Conferences, 2017
The possibility of a direct mass measurement of RR Lyrae variable stars in binary systems has remained elusive for many years, due to the apparent paucity of such systems.
Hajdu Gergely, Catelan Márcio
doaj   +1 more source