恒星形成區(qū)的云核和星團
發(fā)布時間：2018-07-16 07:48
【摘要】：利用青海站13.7 m毫米波望遠鏡對17個與星團成協(xié)的恒星形成區(qū)進行了~(12)CO(J=1-0)、~(13)CO(J=1-0)和C~(18)O(J=1-0)的同時成圖觀測.除了IRAS04547+4753,這些源均探測到較強的C~(18)O(J=1-0)的譜線發(fā)射.由于分子云的大小不同,有13個源觀測到~(13)CO(J=1-0)譜線積分強度極大值的一半處,其他源因分子云延展范圍較大,沒有進行大面積的成圖觀測.基于觀測數(shù)據(jù),計算了各云核的譜線線寬、亮溫度、尺度、密度和質(zhì)量等,~(13)CO和C~(13)O云核的維里質(zhì)量與局部熱動平衡(LTE)質(zhì)量之比分別為0.66和0.74,它們接近于維里平衡狀態(tài).為了從形態(tài)方面比較云核與星團,將譜線的積分強度圖與2MASS的K波段圖像疊加.同時,計算了與云核成協(xié)的星團的大小和質(zhì)量,數(shù)據(jù)采用了2MASS的近紅外點源測光結(jié)果.基于云核與星團的質(zhì)量結(jié)果,計算了分子云的恒星形成效率,大致在10%～30%的范圍.
[Abstract]:Using the 13.7 m millimeter wave telescope of Qinghai station, the simultaneous mapping of ~ (12) CO (J _ (1-0) ~ (13) CO (J _ (1) O) and C ~ (18) O (J _ (1 ~ 0) has been carried out in 17 star forming regions associated with star clusters. With the exception of IRAS04547 4753, these sources have detected strong emission lines of C18O (JO1-0). Due to the difference of molecular cloud size, 13 sources have observed half of the maximum intensity of 13CO (JN1-0) spectral line, and the other sources have not made a large area mapping observation because of the extended range of molecular cloud. Based on the observed data, the ratios of the virial mass of 13CO and C13O cloud nuclei to the local thermodynamic equilibrium (LTE) mass are calculated to be 0.66 and 0.74 respectively, which are close to the state of the virial equilibrium, and the spectral line width, bright temperature, scale, density and mass of the cloud nuclei are calculated as 0.66 and 0.74 respectively. In order to compare cloud nuclei with star clusters in morphology, the integral intensity map of the spectral line is superposed with the K-band image of 2MASS. At the same time, the size and mass of star clusters associated with cloud nuclei are calculated. The data are measured by using 2MASS near infrared point source photometry. Based on the mass results of cloud nuclei and clusters, the star formation efficiency of molecular clouds is calculated in the range of 10 ~ 30%.
【作者單位】： 中國科學院紫金山天文臺;中國科學院研究生院;
【基金】：國家自然科學基金項目(10873037)資助
【分類號】：P152
，
本文編號：2125727
[Abstract]:Using the 13.7 m millimeter wave telescope of Qinghai station, the simultaneous mapping of ~ (12) CO (J _ (1-0) ~ (13) CO (J _ (1) O) and C ~ (18) O (J _ (1 ~ 0) has been carried out in 17 star forming regions associated with star clusters. With the exception of IRAS04547 4753, these sources have detected strong emission lines of C18O (JO1-0). Due to the difference of molecular cloud size, 13 sources have observed half of the maximum intensity of 13CO (JN1-0) spectral line, and the other sources have not made a large area mapping observation because of the extended range of molecular cloud. Based on the observed data, the ratios of the virial mass of 13CO and C13O cloud nuclei to the local thermodynamic equilibrium (LTE) mass are calculated to be 0.66 and 0.74 respectively, which are close to the state of the virial equilibrium, and the spectral line width, bright temperature, scale, density and mass of the cloud nuclei are calculated as 0.66 and 0.74 respectively. In order to compare cloud nuclei with star clusters in morphology, the integral intensity map of the spectral line is superposed with the K-band image of 2MASS. At the same time, the size and mass of star clusters associated with cloud nuclei are calculated. The data are measured by using 2MASS near infrared point source photometry. Based on the mass results of cloud nuclei and clusters, the star formation efficiency of molecular clouds is calculated in the range of 10 ~ 30%.
【作者單位】： 中國科學院紫金山天文臺;中國科學院研究生院;
【基金】：國家自然科學基金項目(10873037)資助
【分類號】：P152
，
本文編號：2125727
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