On the Blazhko Effect in Rr Lyrae Stars

Buchler, J. R.; Kollath, Zoltán

doi:10.1088/0004-637x/731/1/24

Cited by 104 publications

(137 citation statements)

References 23 publications

Supporting

Mentioning

125

Contrasting

Unclassified

Order By: Relevance

“…However, the CCD data, especially when combined with the better seeing conditions at CTIO and the Magellan site, permitted extraction of just the flux from EC 20058−5234 using synthetic aperture techniques. This effect makes it non-trivial to search for amplitude modulation, which, particularly for RR Lyrae stars, is known to be coupled to phase modulation (the Blazhko effect; see, e.g., Buchler & Kolláth 2011). However, if the pulsation amplitudes are intrinsically constant, the ratio of amplitudes from one set to another should be constant.…”

Section: Testing For Stabilitymentioning

confidence: 99%

PERIODIC VARIATIONS IN THEO–CDIAGRAMS OF FIVE PULSATION FREQUENCIES OF THE DB WHITE DWARF EC 20058–5234

Dalessio

Sullivan

Provençal

et al. 2013

ApJ

View full text Add to dashboard Cite

Variations in the pulsation arrival time of five independent pulsation frequencies of the DB white dwarf EC 20058−5234 individually imitate the effects of reflex motion induced by a planet or companion but are inconsistent when considered in unison. The pulsation frequencies vary periodically in a 12.9 year cycle and undergo secular changes that are inconsistent with simple neutrino plus photon-cooling models. The magnitude of the periodic and secular variations increases with the period of the pulsations, possibly hinting that the corresponding physical mechanism is located near the surface of the star. The phase of the periodic variations appears coupled to the sign of the secular variations. The standards for pulsation-timing-based detection of planetary companions around pulsating white dwarfs, and possibly other variables such as subdwarf B stars, should be re-evaluated. The physical mechanism responsible for this surprising result may involve a redistribution of angular momentum or a magnetic cycle. Additionally, variations in a supposed combination frequency are shown to match the sum of the variations of the parent frequencies to remarkable precision, an expected but unprecedented confirmation of theoretical predictions.

show abstract

Section: Testing For Stabilitymentioning

confidence: 99%

PERIODIC VARIATIONS IN THEO–CDIAGRAMS OF FIVE PULSATION FREQUENCIES OF THE DB WHITE DWARF EC 20058–5234

Dalessio

Sullivan

Provençal

et al. 2013

ApJ

View full text Add to dashboard Cite

show abstract

“…The first quantitative tests of this idea found serious inconsistencies between the theory and observations Molnár et al 2012a). Buchler & Kolláth (2011) suggested a model where the modulation caused by a resonance coupling between a low order radial (typically fundamental) mode and a high order radial (the so-called strange) mode. This model is based on the amplitude equation formalism, but it has not been tested yet by hydrodynamic computations.…”

Section: Introductionmentioning

confidence: 99%

LONG-TIMESCALE BEHAVIOR OF THE BLAZHKO EFFECT FROM RECTIFIED KEPLER DATA

Benkő

Plachy

Szabo

et al. 2014

ApJS

163

View full text Add to dashboard Cite

In order to benefit from the four year unprecedented precision of the Kepler data, we extracted light curves from the pixel photometric data of the Kepler space telescope for 15 Blazhko RR Lyrae stars. To collect all the flux from a given target as accurately as possible, we defined tailor-made apertures for each star and quarter. In some cases, the aperture finding process yielded sub-optimal results, because some flux have been lost even if the aperture contains all available pixels around the star. This fact stresses the importance of those methods that rely on the whole light curve instead of focusing on the extrema (O − C diagrams and other amplitude independent methods). We carried out detailed Fourier analysis of the light curves and the amplitude independent O − C diagram. We found 12 (80%) multiperiodically modulated stars in our sample. This ratio is much higher than previously found. Resonant coupling between radial modes, a recent theory for explaining the Blazhko effect, allows single, multiperiodic, or even chaotic modulations. Among the stars with two modulations, we found three stars (V355 Lyr, V366 Lyr, and V450 Lyr) where one of the periods dominates in amplitude modulation, but the other period has a larger frequency modulation amplitude. The ratio between the primary and secondary modulation periods is almost always very close to the ratios of small integer numbers. It may indicate the effect of undiscovered resonances. Furthermore, we detected the excitation of the second radial overtone mode f 2 for three stars where this feature was formerly unknown. Our data set comprises the longest continuous, most precise observations of Blazhko RR Lyrae stars ever published. These data are made publicly available and will be unrivaled for years to come.

show abstract

“…V5 exhibits some deviations from regularity in its B light curve, which could be an indication of some instrumental problems (due perhaps to close stars) or possibly the Blazhko effect (e.g., Buchler & Kolláth 2011), whereas V36 appears to be undergoing multi-periodic non-radial pulsations (see the discussion by Kopacki et al 2003). The only star of the RRab type is V8.…”

mentioning

confidence: 98%

Constraints on the Distance Moduli, Helium, and Metal Abundances, and Ages of Globular Clusters from Their RR Lyrae and Non-variable Horizontal Branch Stars. II. Multiple Stellar Populations in 47 Tuc, M3, and M13

Denissenkov

VandenBerg

Kopacki

et al. 2017

ApJ

View full text Add to dashboard Cite

We present a new set of horizontal-branch (HB) models computed with the MESA stellar evolution code. The models adopt α-enhanced Asplund et al. (2009) 6 Gyr, whereas M 13 has ∆Y 0 ∼ 0.08 and (m − M ) V = 14.42, implying an age of 12.9 Gyr. Mass loss during giant-branch evolution and ∆Y 0 appear to be the primary second parameters for M 3 and M 13. New observations for 7 of the 9 known RR Lyrae in M 13 are also reported. Surprisingly, periods predicted for the c-type variables tend to be too high (by up to ∼ 0.1 d).

show abstract

On the Blazhko Effect in Rr Lyrae Stars

Cited by 104 publications

References 23 publications

PERIODIC VARIATIONS IN THEO–CDIAGRAMS OF FIVE PULSATION FREQUENCIES OF THE DB WHITE DWARF EC 20058–5234

PERIODIC VARIATIONS IN THEO–CDIAGRAMS OF FIVE PULSATION FREQUENCIES OF THE DB WHITE DWARF EC 20058–5234

LONG-TIMESCALE BEHAVIOR OF THE BLAZHKO EFFECT FROM RECTIFIED KEPLER DATA

Constraints on the Distance Moduli, Helium, and Metal Abundances, and Ages of Globular Clusters from Their RR Lyrae and Non-variable Horizontal Branch Stars. II. Multiple Stellar Populations in 47 Tuc, M3, and M13

Contact Info

Product

Resources

About