인문학
사회과학
자연과학
공학
의약학
농수해양학
예술체육학
복합학
DBpia AI
AI 에이전트
AI 아이디어
AI 리더
AI 뷰어
Citeasy
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지원사업
학술연구/단체지원/교육 등 연구자 활동을 지속하도록 DBpia가 지원하고 있어요.
커뮤니티
연구자들이 자신의 연구와 전문성을 널리 알리고, 새로운 협력의 기회를 만들 수 있는 네트워킹 공간이에요.
초록·키워드
Context . Deuterium fractionation is a well-established evolutionary tracer in low-mass star formation, but its applicability to the high-mass regime remains an open question. In this context, the abundances and ratios of different deuterated species have often been proposed as reliable evolutionary indicators for different stages of the high-mass star formation process. Aims . In this study, we investigate the role of N 2 H+ and key deuterated molecules (o-H 2 D + and N 2 D + ) as tracers of the different stages of the high-mass star formation process. We assess whether their abundance ratios can serve as reliable evolutionary indicators. Methods . We conducted APEX observations of o-H 2 D + (1 10 –1 11 ), N 2 H + (4−3), and N 2 D + (3−2) in a sample of 40 high-mass clumps at different evolutionary stages, selected from the ATLASGAL survey. Molecular column densities and abundances relative to H 2 , X , were derived through spectral line modelling, both under local thermodynamic equilibrium (LTE) and non-LTE conditions. Results . The o-H 2 D + column densities show the smallest deviation from LTE conditions when derived under non-LTE assumptions. In contrast, N 2 H + shows the largest discrepancy between the column densities derived from LTE and non-LTE. In all the cases discussed, we found that X (o-H 2 D + ) decreases more significantly with each respective evolutionary stage than in the case of X (N 2 D + ); whereas X (N 2 H + ) increases slightly. Therefore, the validity of the X (o-H 2 D + )/ X (N 2 D + ) ratio as a reliable evolutionary indicator, recently proposed as a promising tracer of the different evolutionary stages, was not observed for this sample. While the deuteration fraction derived from N 2 D + and N 2 H + clearly decreases with clump evolution, the interpretation of this trend is complex, given the different distribution of the two tracers. Conclusions . Our results suggest that a careful consideration of the observational biases and beam-dilution effects are crucial for an accurate interpretation of the evolution of the deuteration process during the high-mass star formation process.
인공지능 문자 인식 모델을 통해 추출된 텍스트로, 일부 오타나 오류가 포함될 수 있으나 지속적으로 개선 중입니다.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.
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