구상성단 M30의 20'.5×20'.5 영역에 대한 CCD UBVI 측광 관측을 수행하여 색-등급도로부터 주계열 전향점과 색지수 VTO=18.63±0.05, (B-V)TO=0.44±0.05, (V-I)TO=0.63±0.05를 얻었으며, 색-색도로부터 E(B-V)=0.05±0.01과 중원소 함량의 지표인 UV 색 초과량 δ(U-B)=0.27±0.01을 얻었다. 측광학적인 방법과 분광 관측 자료를 이용하여 중원소 함량 [Fe/H]=-2.05±0.09를 구하였다. 관측된 M30의 광도 함수는 이론적 모델에 비하여 전향점 부근에 비하여 적색 거성열의 초과 현상을 보였다. Hipparcos 위성에서 측정된 삼각 시차로부터 거리가 알려진 준왜성을 이용하여 주계열 맞추기를 하여 거리 지수 (m-M)o=14.75±0.12를 구하였다. 헬륨 함량을 구하기 위하여 R과 R' 방법을 사용하여 Y(R)=0.23±0.02, Y(R')=0.29±0.02를 얻었다. 성단의 나이는 적용하는 방법과 모델에 따라서 10.7 Gyr에서 17 Gyr까지 분산을 보인다.
A large scatter of the chemical abundances among globular cluster red giants has been observed. Especially the chemical elements C, N, O, Na, Mg, and Al vary form star to star within globular clusters. Except for ω Cen and M22, most globular clusters could be considered to be monometallic of their iron peak elements within error ranges. The variations in light elements among globuar cluster giants appear much more pronounced than in field halo giants of comparable Fe-peak metallicity. It has been found that in general the nitrogen abundance is anticorrelated with both carbon and oxygen, while it is correlated with Na and AI. These intracluster abundance inhomogeneities can be interpreted either by mixing of nucleosythesized material from the deep stellar interior during the red giant branch phase of evolution or by inhomogeneities of primordially processed material, from which the stars were formed. The simple way of distingushing between two senarios is to obtain the element abundances of main-sequence stars in globular clusters, which are too faint for high resolution spectroscopic studies until now. Both 'evolutionary' and 'primodial' origins are accepted for explanations of abundance variations among red giants and CN-CH anticorrelations among main-sequence stars in globular clusters. This paper reviews chemical abundances of light elements among globular cluster giants, with brief reviews of cannonical stellar evolution of low mass stars after main-sequence and deep mixing for abundance variations of cluster giants, and a possible connection between deep mixing and second parameter.
We review the early historical developement of astronomical spectrographs, properties of emission line spectra of HII regions in spiral galaxies, and absorption line features of galactic globular clusters. Emission line spectra of HII regions within three spiral galaxies NGC 300, NGC 1365, and NGC 7793, which were observed from AAT/IPCS, had been analysed, and we discuss the abundances of elements in HII regions and the radial abundace gradients through the galaxies. The radial UBV color variations of two globular clusters, NGC 1851 and NGC 2808, were examined for correlations with radial variations of several absorption lines in the integrated spectra, which were obtained from SAAO 74 inch telescope and image tube spectrograph. Nine giant star's spectra in NGC 3201 were also obtained and analysed for the radial abundance gradients in the globular cluster. The results show that the presence of a radial color gradient in a globular cluster is correlated with the presence of abundance gradients. Finally, we suggest some scientific programs for the new high dispersion spectrograph, which will be installed to the BOAO 1.8m telescope.