• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The Astrophysical journal >GEOMETRY OF THE LARGE MAGELLANIC CLOUD DISK: RESULTS FROM MACHO AND THE TWO MICRON ALL SKY SURVEY
【24h】

GEOMETRY OF THE LARGE MAGELLANIC CLOUD DISK: RESULTS FROM MACHO AND THE TWO MICRON ALL SKY SURVEY

机译：大型麦哲伦云盘的几何形状：来自Macho和两个MICRON ALL SKY调查的结果

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We present a detailed study of the viewing angles and geometry of the inner LMC (ρ approx< 4°) based on a sample of more than 2000 MACHO Cepheids with complete {VR}_(KC) light cunves and single-phase Two Micron All Sky Survey (2MASS) JHK_s observations. The sample is considerably larger than any previously studied subset of LMC Cepheids and has an improved areal coverage. Single-epoch random-phase 2MASS photometry is corrected using MACHO V light curves to derive mean JHK_s magnitudes. We analyze the resulting period-luminosity relations in VRJHK_s to recover statistical reddening and distance to each individual Cepheid, with respect to the mean distance modulus and reddening of the LMC. By fitting a plane solution to the derived individual distance moduli, the values of LMC viewing angles are obtained: position angle θ= 151°.0+-2°.4, inclination i = 30°.7 +- 1°1. In the so-called ring analysis, we find a strong dependence of the derived viewing angles on the adopted center of the LMC, which we interpret as being due to deviations from planar geometry. Analysis of residuals from the plane fit indicates the presence of a symmetric warp in the LMC disk and the bar elevated above the disk plane. Nonplanar geometry of the inner LMC explains a broad range for values of i and θ in the literature and suggests caution when deriving viewing angles from inner LMC data.
机译：我们基于2000多个MACHO造父变星的样本，其中包括完整的{VR} _（KC）光楔和单相“两微米微米”，对内部LMC的视角和几何形状（ρ约<4°）进行了详细研究。 JHK的天空观测（2MASS）观测。该样本比以前研究的LMC造父变星的子集大得多，并且具有改善的面积覆盖率。使用MACHO V光曲线对单周期随机相位2MASS光度进行校正，以得出平均JHK_s幅度。我们分析了VRJHK_s中产生的周期-光度关系，以恢复相对于LMC的平均距离模量和变红的统计变红和到每个造父变星的距离。通过将平面解拟合到导出的各个距离模量，可以得到LMC视角的值：位置角θ= 151°.0 + -2°.4，倾角i = 30°.7 + 1°1。在所谓的环分析中，我们发现派生的视角对LMC采用的中心有很大的依赖性，我们认为这是由于与平面几何形状的偏差。平面拟合的残差分析表明，LMC磁盘中存在对称的翘曲，并且在磁盘平面上方升高的钢筋。内部LMC的非平面几何形状在文献中解释了i和θ值的广泛范围，并建议从内部LMC数据得出视角时要谨慎。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号