首页     开始     To Survive in the Universe    
Inhabited Sky
    News@Sky     天文图片     收集     论坛     Blog New!     常见问题     新闻     登录  

HD 33110


目录

图像

上传图像

DSS Images   Other Images


相关文章

Herbig Ae/Be Stars in nearby OB Associations
We have carried out a study of the early-type stars in nearby OBassociations spanning an age range of ~3-16 Myr, with the aim ofdetermining the fraction of stars that belong to the Herbig Ae/Be class.We studied the B, A, and F stars in the nearby (<=500 pc) OBassociations Upper Scorpius, Perseus OB2, Lacerta OB1, and Orion OB1,with membership determined from Hipparcos data. We also included in ourstudy the early-type stars in the Trumpler 37 cluster, part of the CepOB2 association. We obtained spectra for 440 Hipparcos stars in theseassociations, from which we determined accurate spectral types, visualextinctions, effective temperatures, luminosities and masses, usingHipparcos photometry. Using colors corrected for reddening, we find thatthe Herbig Ae/Be stars and the classical Be (CBe) stars occupy clearlydifferent regions in the JHK diagram. Thus, we use the location on theJHK diagram, as well as the presence of emission lines and of strong 12μm flux relative to the visual, to identify the Herbig Ae/Be stars inthe associations. We find that the Herbig Ae/Be stars constitute a smallfraction of the early-type stellar population even in the youngerassociations. Comparing the data from associations with different agesand assuming that the near-infrared excess in the Herbig Ae/Be starsarises from optically thick dusty inner disks, we determined theevolution of the inner disk frequency with age. We find that the innerdisk frequency in the age range 3-10 Myr in intermediate-mass stars islower than that in the low-mass stars (<1 Msolar) inparticular, it is a factor of ~10 lower at ~3 Myr. This indicates thatthe timescales for disk evolution are much shorter in theintermediate-mass stars, which could be a consequence of more efficientmechanisms of inner disk dispersal (viscous evolution, dust growth, andsettling toward the midplane).

提交文章


相关链接

  • - 没有找到链接 -
提交链接


下列团体成员


观测天体数据

星座:獵戶座
右阿森松:05h08m06.38s
赤纬:+03°44'54.9"
视星:7.243
距离:143.885 天文距离
右阿森松适当运动:-2.5
赤纬适当运动:-2.1
B-T magnitude:7.338
V-T magnitude:7.251

目录:
适当名称   (Edit)
HD 1989HD 33110
TYCHO-2 2000TYC 103-590-1
USNO-A2.0USNO-A2 0900-01378797
HIPHIP 23899

→ 要求更多目录从vizier