한국지구과학회지 (Journal of the Korean earth science society)

  • 제37권7호
  • /
  • Pages.389-397
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  • 2016
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  • 1225-6692(pISSN)
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  • 2287-4518(eISSN)
한국지구과학회 (The Korean Earth Science Society)
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δ Scuti형 변광성 BO Lyn의 근적외선 광도곡선 분석

An Analysis of Near-infrared Light Curves of δ Scuti Variable BO Lyn

  • 임지혜 (한국교원대학교 지구과학교육과) ;
  • 손정주 (한국교원대학교 지구과학교육과)
  • Lim, Ji-Hye (Department of Earth Science Education, Korea National University of Education) ;
  • Sohn, Jungjoo (Department of Earth Science Education, Korea National University of Education)
  • 투고 : 2016.08.12
  • 심사 : 2016.11.29
  • 발행 : 2016.12.31
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초록

${\delta}$ Scuti형 변광성 BO Lyn의 파장에 따른 광도곡선 차이를 알아보기 위해서 보현산천문대의 1.8m 반사망원경과 적외선 검출기 KASINICS를 이용한 측광 관측을 수행하였다. 2011년 3월 26일부터 4월 1일까지 총 7일간의 관측 자료로 J, H, Ks필터 광도곡선을 얻어 기존에 보고된 V필터에서의 광도곡선과 비교하여 주기, 극대점, 진폭, 형태에 대한 차이를 알아보았다. 적외선 광도곡선의 주기 분석 결과 단일 주파수해 $f_1=10.712cycle/day$, 주기$P=0.09335{\pm}0.00002days$의 값을 얻었으며, 파장에 따른 주기의 차이는 나타나지 않았다. 적외선에서는 $2f_1$에 해당하는 주파수가 검출되었는데, 이는 고진폭 ${\delta}$ Scuti형 변광성의 특징인 비대칭적인 광도곡선의 형태를 잘 설명해준다. 극대점의 위치를 비교한 결과 계산된 V필터의 예상 극대점보다 관측된 적외선 극대점이 전체 주기의 약 0.3에 해당하는 만큼 더 늦게 나타났다. 진폭은 ${\Delta}J/{\Delta}V=0.328$, ${\Delta}H/{\Delta}V=0.216$, ${\Delta}Ks/{\Delta}V=0.211$로 파장이 길어질수록 변광의 폭이 더 작게 나타났다. 파장에 따른 극대점의 지연과 변광폭의 차이는 맥동변광성의 밝기 변화가 주로 온도변화에 기인하기 때문인 것으로 여겨진다.

In order to investigate the light curve difference in visual and infrared wavelength of ${\delta}$ Scuti variable Bo Lyn, observations were performed using BOAO 1.8m reflecting telescope and an infrared detector, KASINICS, with J, H, and Ks filters. Infrared light curves of total 7 nights were obtained between March and April in 2011, and those were compared to the V-filter light curve to examine the differences in period, time of maximum light, amplitude, and shape. From the periodic analysis of infrared light curve, a single frequency of $f_1=10.712cycle/day$, $P=0.09335{\pm}0.00002days$ was obtained, and there was no difference in the period along different wavelengths. In the infrared light curve, a frequency of $2f_1$ was detected. This frequency well explains the asymmetric shape of light curve, one of the characteristics of high-amplitude ${\delta}$ Scuti variables. We compared the locations of the measured infrared maxima and the predicted maxima of V-filter, finding that the times of maxima were delayed about 0.3 phase at infrared wavelengths. Amplitude ratios were adopted to be ${\Delta}J/{\Delta}V=0.328$, ${\Delta}H/{\Delta}V=0.216$, and ${\Delta}Ks/{\Delta}V=0.211$, with the range of variation being smaller at longer wavelengths. It seems that the differences in the times of maxima and amplitude occurred because the changes in brightness of a pulsating variable star are mainly caused by the change in temperature.

키워드

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