First observations of the water masers with the Urumqi 25m radio telescope

来源 :中国科学A辑 | 被引量 : 0次 | 上传用户:cai2001m
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
A new radio spectral receiving system has been installed on the 25 m radio telescope of the Urumqi Astronomical Observatory. The back end is a surface acoustic wave chirp transform spectrometer (SAW CZT), used for the first time in radio astronomy. The calibration of the line observations has carefully been investigated for the new-type spectrometer. In order to test the feasibility of the prototype spectrometer, we observed water maser emission from a number of known Galactic sources. We describe the observed spectra of W49N, W3(OH), 2248+600 and 1909+090. We found that W49N spectrum showed high-velocity features ranging from -330 to 146 km s-1. In comparison with the spectra observed by Medicina, the feature at the LSR velocity -52 km s-1 in the W3(OH) presented the rapid variation in flux density.
其他文献
Down-core variation in planktonic foraminifera (PF) at Site 1143 (ODP 184) has dis closed the evolution of upper water-column structure over the last 12 Ma in t
High-resolution δ13C records are presented for the Miocene benthic foraminifers Cibici doides wuellerstorfi and C. kullenbergi (24-5 Ma) and the planktonic for
目的:了解学龄前儿童视力异常状况,对视力异常儿童提出干预措施.方法:采用美国伟伦公司"Suresight"视力筛选仪,对1326名入园体检的学龄前儿童进行视力筛查.结果:各年龄组散光
A great number of calcareous nannofossils have been found in the deep-sea sediments of 2.32 Ma at ODP Site 1143 located in the Nansha area, the southern South C
The high-resolution quantitative analysis of the planktonic foraminifera and the δ18O records of the section between 96.49-137.6 mcd at ODP Site 1144 on the co
Based on the stable isotopic analysis of more than 1000 samples of planktonic and benthic foraminifers from ODP Site 1148 in the northern South China Sea (SCS),
铁属于机体必需的营养元素之一,起着重要的生物学功能.铁过多也会给细胞和组织带来危害.而近年来关于铁与糖尿病的关系日益受到学者们的关注,成为一个研究的热点.本文就此方
分支机构财务监管有效与否对企业发展至关重要,但只要明确了监管要素的"四化",即组织架构明晰化、权责界定清晰化、规章制度系统化、考核奖罚明确化,并能够有效推行实施,就可