CCD PHOTOMETRY OF THE GLOBULAR CLUSTER M30

구상 성단 M30의 측광학적 연구

  • 임홍서 (연세대학교 천문대기과학과) ;
  • 천문석 (연세대학교 천문대기과학과) ;
  • 이영욱 (연세대학교 천문대기과학과)
  • Published : 1996.06.01

Abstract

We present UBV CCD photomety of the metal-poor globular cluster M30. The data were obtained using the 40 inch telescope at Mt. Stromlo and Siding Spring Observatory (MSSSO). We used DAOPHOT CCD reduction package in order to obtain Color-Magnitude Diagram (CMD). We have derived some fundametal parameters of the globular cluster such as metal abundance ([Fe/H]), helium abundance (Y), and distance modulus (m-M) from the CMD. The derived parameters were [Fe/H]=-2.50, Y=0.28, and (m-M)=14.64. From the latter, the distance of 8.3kpc is obtained. Despite the photometric uncertainty near the main-sequence turnoff, we estimate the age of M30 to be 1.6${\pm}$3 Gyrs from the Revised Yale Isocyrones. If [O/Fe]=+0.4, this age will be reduced to 14.2${\pm}$3 Gyrs.

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