English  |  正體中文  |  简体中文  |  全文筆數/總筆數 : 80990/80990 (100%)
造訪人次 : 41145166      線上人數 : 659
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
搜尋範圍 查詢小技巧:
  • 您可在西文檢索詞彙前後加上"雙引號",以獲取較精準的檢索結果
  • 若欲以作者姓名搜尋,建議至進階搜尋限定作者欄位,可獲得較完整資料
  • 進階搜尋


    請使用永久網址來引用或連結此文件: http://ir.lib.ncu.edu.tw/handle/987654321/50844


    題名: A multiwavelength polarimetric study towards the open cluster NGC 1893
    作者: Eswaraiah,C;Pandey,AK;Maheswar,G;Medhi,BJ;Pandey,JC;Ojha,DK;Chen,WP
    貢獻者: 天文研究所
    關鍵詞: OPTICAL POLARIZATION OBSERVATIONS;MAIN-SEQUENCE STARS;WAVELENGTH DEPENDENCE;INTERSTELLAR GRAINS;MAXIMUM POLARIZATION;OB ASSOCIATIONS;REGION;EXTINCTION;PHOTOMETRY;NGC-1893
    日期: 2011
    上傳時間: 2012-03-27 18:11:18 (UTC+8)
    出版者: 國立中央大學
    摘要: We present multiwavelength linear polarimetric observations for 44 stars of the NGC 1893 young open cluster region along with V-band polarimetric observations of stars of four other open clusters located between l similar to 160 degrees and 175 degrees. We found evidence for the presence of two dust layers located at a distance of similar to 170 and similar to 360 pc. The dust layers produce a polarization P(V) similar to 2.2 per cent. It is evident from the clusters studied in this work that, in the Galactic longitude range from l similar to 160 degrees to 175 degrees and within the Galactic plane (vertical bar b vertical bar < 2 degrees), the polarization angles remain almost constant, with a mean of similar to 163 degrees and a dispersion of 6 degrees. The small dispersion in polarization angle could be due to the presence of a uniform dust layer beyond 1 kpc. Present observations reveal that in the case of NGC 1893, the foreground two dust layers, in addition to the intracluster medium, seem to be responsible for the polarization effects. It is also found that towards the direction of NGC 1893, the dust layer that exists between 2 and 3 kpc has a negligible contribution towards the total observed polarization. The weighted mean for percentage of polarization (P(max)) and the wavelength at maximum polarization (lambda(max)) are found to be 2.59 +/- 0.02 per cent and 0.55 +/- 0.01 mu m, respectively. The estimated mean value of lambda(max) indicates that the average size of the dust grains within the cluster is similar to that in the general interstellar medium. The spatial variation of the polarization is found to decrease towards the outer region of the cluster. In this work, we support the notion, as has already been shown in previous studies, that polarimetry, in combination with the (U - B)-(B - V) colour-colour diagram, is a useful tool for identifying non-members in a cluster.
    關聯: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
    顯示於類別:[天文研究所] 期刊論文

    文件中的檔案:

    檔案 描述 大小格式瀏覽次數
    index.html0KbHTML588檢視/開啟


    在NCUIR中所有的資料項目都受到原著作權保護.

    社群 sharing

    ::: Copyright National Central University. | 國立中央大學圖書館版權所有 | 收藏本站 | 設為首頁 | 最佳瀏覽畫面: 1024*768 | 建站日期:8-24-2009 :::
    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - 隱私權政策聲明