Blazhko modulation in the infrared

J. Jurcsik, G. Hajdu, I. Dékány, J. Nuspl, M. Catelan, E. K. Grebel

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

We present first direct evidence of modulation in the K band of Blazhko-type RR Lyrae stars that are identified by their secular modulations in the I-band data of Optical Gravitational Lensing Experiment-IV. Amethod has been developed to decompose theK-band light variation into two parts originating from the temperature and the radius changes using synthetic data of atmosphere-model grids. The amplitudes of the temperature and the radius variations derived from the method for non-Blazhko RRab stars are in very good agreement with the results of the Baade-Wesselink analysis of RRab stars in the M3 globular cluster confirming the applicability and correctness of the method. It has been found that the Blazhko modulation is primarily driven by the change in the temperature variation. The radius variation plays a marginal part, moreover it has an opposite sign as if the Blazhko effect was caused by the radii variations. This result reinforces the previous finding based on the Baade-Wesselink analysis of M3 (NGC 5272) RR Lyrae, that significant modulation of the radius variations can only be detected in radial-velocity measurements, which relies on spectral lines that form in the uppermost atmospheric layers. Our result gives the first insight into the energetics and dynamics of the Blazhko phenomenon, hence it puts strong constraints on its possible physical explanations.

Original languageEnglish
Pages (from-to)4208-4222
Number of pages15
JournalMonthly Notices of the Royal Astronomical Society
Volume475
Issue number3
DOIs
Publication statusPublished - Apr 1 2018

Fingerprint

modulation
radii
temperature
stars
energetics
atmosphere
extremely high frequencies
globular clusters
velocity measurement
radial velocity
line spectra
experiment
grids
atmospheres
analysis
method
effect

Keywords

  • Galaxy: bulge
  • Infrared: stars
  • Stars: horizontal branch
  • Stars: oscillations
  • Stars: variables: RR Lyrae
  • Techniques: photometric

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Blazhko modulation in the infrared. / Jurcsik, J.; Hajdu, G.; Dékány, I.; Nuspl, J.; Catelan, M.; Grebel, E. K.

In: Monthly Notices of the Royal Astronomical Society, Vol. 475, No. 3, 01.04.2018, p. 4208-4222.

Research output: Contribution to journalArticle

Jurcsik, J, Hajdu, G, Dékány, I, Nuspl, J, Catelan, M & Grebel, EK 2018, 'Blazhko modulation in the infrared', Monthly Notices of the Royal Astronomical Society, vol. 475, no. 3, pp. 4208-4222. https://doi.org/10.1093/MNRAS/STY112
Jurcsik, J. ; Hajdu, G. ; Dékány, I. ; Nuspl, J. ; Catelan, M. ; Grebel, E. K. / Blazhko modulation in the infrared. In: Monthly Notices of the Royal Astronomical Society. 2018 ; Vol. 475, No. 3. pp. 4208-4222.
@article{defb8892c2644a939fa07d07d9061b81,
title = "Blazhko modulation in the infrared",
abstract = "We present first direct evidence of modulation in the K band of Blazhko-type RR Lyrae stars that are identified by their secular modulations in the I-band data of Optical Gravitational Lensing Experiment-IV. Amethod has been developed to decompose theK-band light variation into two parts originating from the temperature and the radius changes using synthetic data of atmosphere-model grids. The amplitudes of the temperature and the radius variations derived from the method for non-Blazhko RRab stars are in very good agreement with the results of the Baade-Wesselink analysis of RRab stars in the M3 globular cluster confirming the applicability and correctness of the method. It has been found that the Blazhko modulation is primarily driven by the change in the temperature variation. The radius variation plays a marginal part, moreover it has an opposite sign as if the Blazhko effect was caused by the radii variations. This result reinforces the previous finding based on the Baade-Wesselink analysis of M3 (NGC 5272) RR Lyrae, that significant modulation of the radius variations can only be detected in radial-velocity measurements, which relies on spectral lines that form in the uppermost atmospheric layers. Our result gives the first insight into the energetics and dynamics of the Blazhko phenomenon, hence it puts strong constraints on its possible physical explanations.",
keywords = "Galaxy: bulge, Infrared: stars, Stars: horizontal branch, Stars: oscillations, Stars: variables: RR Lyrae, Techniques: photometric",
author = "J. Jurcsik and G. Hajdu and I. D{\'e}k{\'a}ny and J. Nuspl and M. Catelan and Grebel, {E. K.}",
year = "2018",
month = "4",
day = "1",
doi = "10.1093/MNRAS/STY112",
language = "English",
volume = "475",
pages = "4208--4222",
journal = "Monthly Notices of the Royal Astronomical Society",
issn = "0035-8711",
publisher = "Oxford University Press",
number = "3",

}

TY - JOUR

T1 - Blazhko modulation in the infrared

AU - Jurcsik, J.

AU - Hajdu, G.

AU - Dékány, I.

AU - Nuspl, J.

AU - Catelan, M.

AU - Grebel, E. K.

PY - 2018/4/1

Y1 - 2018/4/1

N2 - We present first direct evidence of modulation in the K band of Blazhko-type RR Lyrae stars that are identified by their secular modulations in the I-band data of Optical Gravitational Lensing Experiment-IV. Amethod has been developed to decompose theK-band light variation into two parts originating from the temperature and the radius changes using synthetic data of atmosphere-model grids. The amplitudes of the temperature and the radius variations derived from the method for non-Blazhko RRab stars are in very good agreement with the results of the Baade-Wesselink analysis of RRab stars in the M3 globular cluster confirming the applicability and correctness of the method. It has been found that the Blazhko modulation is primarily driven by the change in the temperature variation. The radius variation plays a marginal part, moreover it has an opposite sign as if the Blazhko effect was caused by the radii variations. This result reinforces the previous finding based on the Baade-Wesselink analysis of M3 (NGC 5272) RR Lyrae, that significant modulation of the radius variations can only be detected in radial-velocity measurements, which relies on spectral lines that form in the uppermost atmospheric layers. Our result gives the first insight into the energetics and dynamics of the Blazhko phenomenon, hence it puts strong constraints on its possible physical explanations.

AB - We present first direct evidence of modulation in the K band of Blazhko-type RR Lyrae stars that are identified by their secular modulations in the I-band data of Optical Gravitational Lensing Experiment-IV. Amethod has been developed to decompose theK-band light variation into two parts originating from the temperature and the radius changes using synthetic data of atmosphere-model grids. The amplitudes of the temperature and the radius variations derived from the method for non-Blazhko RRab stars are in very good agreement with the results of the Baade-Wesselink analysis of RRab stars in the M3 globular cluster confirming the applicability and correctness of the method. It has been found that the Blazhko modulation is primarily driven by the change in the temperature variation. The radius variation plays a marginal part, moreover it has an opposite sign as if the Blazhko effect was caused by the radii variations. This result reinforces the previous finding based on the Baade-Wesselink analysis of M3 (NGC 5272) RR Lyrae, that significant modulation of the radius variations can only be detected in radial-velocity measurements, which relies on spectral lines that form in the uppermost atmospheric layers. Our result gives the first insight into the energetics and dynamics of the Blazhko phenomenon, hence it puts strong constraints on its possible physical explanations.

KW - Galaxy: bulge

KW - Infrared: stars

KW - Stars: horizontal branch

KW - Stars: oscillations

KW - Stars: variables: RR Lyrae

KW - Techniques: photometric

UR - http://www.scopus.com/inward/record.url?scp=85043593581&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85043593581&partnerID=8YFLogxK

U2 - 10.1093/MNRAS/STY112

DO - 10.1093/MNRAS/STY112

M3 - Article

AN - SCOPUS:85043593581

VL - 475

SP - 4208

EP - 4222

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 3

ER -