인문학
사회과학
자연과학
공학
의약학
농수해양학
예술체육학
복합학
DBpia AI
AI 에이전트
AI 아이디어
AI 리더
AI 뷰어
Citeasy
크롬 서지관리 다운로드
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
Aims. Our aim is to provide an observational view of the old disc structure of the Milky Way galaxy using the distribution of red clump (RC) stars. The spiral arms, warp structure, and other asymmetries present in the disc are revisited using a systematic study of RC star counts over the disc of the Galaxy. Methods. We developed a method for systematically extracting the RC stars from a 2MASS ( J − K s , J ) colour-magnitude diagram of 1° ×1° bins in ℓ × b , covering the range 40° ≤ ℓ ≤ 320° and −10° ≤ b ≤ 10°. 2MASS data continue to be important because we are able to identify and trace the RC stars to much farther distances than in any optical survey of the Galactic disc. The foreground star contamination in the selected sample was removed using the accurate astrometric data from Gaia EDR3. We analysed the spiral arms and asymmetry in the Galaxy above and below the Galactic plane in galactocentric coordinates. Results. We have generated a face-on-view ( XY -plane) of the Galaxy depicting the density distribution and count ratio above and below the Galactic plane. The resulting over-density of RC stars traces the continuous morphology of the Outer arm from the second to the third Galactic quadrant. This is the first study to map the Outer arms across the disc using RC stars. Through this study, we are able to trace the Outer arm well into the third Galactic quadrant for the first time. In addition to the spiral structures, we also see a wave-like asymmetry above and below the Galactic plane with respect to longitudes, indicating the warp structure. The warp structure is studied systematically by tracing the ratio of RC stars above and below the Galactic plane. We provide the first direct observational evidence of the asymmetry in the outer spiral arms, confirming that the spiral arms traced by the older population are also warped, similar to the disc.
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.
최근 본 자료 전체보기
