Investigation of variable star candidates in the globular cluster NGC 5024 (M53)

D. M. Bramich, A. Arellano Ferro, R. Figuera Jaimes, Sunetra Giridhar

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

We have performed a careful investigation of the 74 candidate variable stars presented by Safonova & Stalin. For this purpose we used our data base of imaging and light curves from Arellano Ferro et al. We find that two candidates are known variable stars, eight candidates were discovered first by Arellano Ferro et al., but would not have been known to Safonova & Stalin at the time of their paper submission, while four candidates are new variables. Three of the new variables are SX Phe type and one is a semiregular (SR) type red giant variable. We also tentatively confirm the presence of true variability in two other candidates, and we are unable to investigate another four candidates because they are not in our data base. However, we find that the remaining 54 candidate variable stars are spurious detections where systematic trends in the light curves have been mistaken for true variability. We believe that the erroneous detections are caused by the adoption of a very low detection threshold used to identify these candidates.

Original languageEnglish
Pages (from-to)2722-2732
Number of pages11
JournalMonthly Notices of the Royal Astronomical Society
Volume424
Issue number4
DOIs
Publication statusPublished - 21 Aug 2012
Externally publishedYes

Fingerprint

variable stars
globular clusters
data bases
light curve
trends
thresholds
curves
detection
data base

Keywords

  • Globular clusters: individual: NGC 5024
  • Stars: variables: general

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Investigation of variable star candidates in the globular cluster NGC 5024 (M53). / Bramich, D. M.; Arellano Ferro, A.; Jaimes, R. Figuera; Giridhar, Sunetra.

In: Monthly Notices of the Royal Astronomical Society, Vol. 424, No. 4, 21.08.2012, p. 2722-2732.

Research output: Contribution to journalArticle

Bramich, D. M. ; Arellano Ferro, A. ; Jaimes, R. Figuera ; Giridhar, Sunetra. / Investigation of variable star candidates in the globular cluster NGC 5024 (M53). In: Monthly Notices of the Royal Astronomical Society. 2012 ; Vol. 424, No. 4. pp. 2722-2732.
@article{5bf85bf013c3408ea9bcd00004c421ea,
title = "Investigation of variable star candidates in the globular cluster NGC 5024 (M53)",
abstract = "We have performed a careful investigation of the 74 candidate variable stars presented by Safonova & Stalin. For this purpose we used our data base of imaging and light curves from Arellano Ferro et al. We find that two candidates are known variable stars, eight candidates were discovered first by Arellano Ferro et al., but would not have been known to Safonova & Stalin at the time of their paper submission, while four candidates are new variables. Three of the new variables are SX Phe type and one is a semiregular (SR) type red giant variable. We also tentatively confirm the presence of true variability in two other candidates, and we are unable to investigate another four candidates because they are not in our data base. However, we find that the remaining 54 candidate variable stars are spurious detections where systematic trends in the light curves have been mistaken for true variability. We believe that the erroneous detections are caused by the adoption of a very low detection threshold used to identify these candidates.",
keywords = "Globular clusters: individual: NGC 5024, Stars: variables: general",
author = "Bramich, {D. M.} and {Arellano Ferro}, A. and Jaimes, {R. Figuera} and Sunetra Giridhar",
year = "2012",
month = "8",
day = "21",
doi = "10.1111/j.1365-2966.2012.21360.x",
language = "English",
volume = "424",
pages = "2722--2732",
journal = "Monthly Notices of the Royal Astronomical Society",
issn = "0035-8711",
publisher = "Oxford University Press",
number = "4",

}

TY - JOUR

T1 - Investigation of variable star candidates in the globular cluster NGC 5024 (M53)

AU - Bramich, D. M.

AU - Arellano Ferro, A.

AU - Jaimes, R. Figuera

AU - Giridhar, Sunetra

PY - 2012/8/21

Y1 - 2012/8/21

N2 - We have performed a careful investigation of the 74 candidate variable stars presented by Safonova & Stalin. For this purpose we used our data base of imaging and light curves from Arellano Ferro et al. We find that two candidates are known variable stars, eight candidates were discovered first by Arellano Ferro et al., but would not have been known to Safonova & Stalin at the time of their paper submission, while four candidates are new variables. Three of the new variables are SX Phe type and one is a semiregular (SR) type red giant variable. We also tentatively confirm the presence of true variability in two other candidates, and we are unable to investigate another four candidates because they are not in our data base. However, we find that the remaining 54 candidate variable stars are spurious detections where systematic trends in the light curves have been mistaken for true variability. We believe that the erroneous detections are caused by the adoption of a very low detection threshold used to identify these candidates.

AB - We have performed a careful investigation of the 74 candidate variable stars presented by Safonova & Stalin. For this purpose we used our data base of imaging and light curves from Arellano Ferro et al. We find that two candidates are known variable stars, eight candidates were discovered first by Arellano Ferro et al., but would not have been known to Safonova & Stalin at the time of their paper submission, while four candidates are new variables. Three of the new variables are SX Phe type and one is a semiregular (SR) type red giant variable. We also tentatively confirm the presence of true variability in two other candidates, and we are unable to investigate another four candidates because they are not in our data base. However, we find that the remaining 54 candidate variable stars are spurious detections where systematic trends in the light curves have been mistaken for true variability. We believe that the erroneous detections are caused by the adoption of a very low detection threshold used to identify these candidates.

KW - Globular clusters: individual: NGC 5024

KW - Stars: variables: general

UR - http://www.scopus.com/inward/record.url?scp=84864958756&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84864958756&partnerID=8YFLogxK

U2 - 10.1111/j.1365-2966.2012.21360.x

DO - 10.1111/j.1365-2966.2012.21360.x

M3 - Article

VL - 424

SP - 2722

EP - 2732

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 4

ER -