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Seeing measurements for the Guoshoujing Telescope (LAMOST) site with DIMM

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Research in Astronomy and Astrophysics 2010年第10期10卷 1061-1070页

作者： Li-yong Liu yong-qiang yao Yi-Ping Wang Jiang-Long Ma Bo-Liang He Hong-Shuai Wang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We present seeing measurements of the Guoshoujing Telescope （formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope- LAMOST） site at Xinglong station during the period from 2007 March 12 to April 25. The measurements were carried out with the Differential Image Motion Monitor （DIMM）, and a total of 9259 data sets was obtained. The median seeing was measured to be 1.1″, with 25% being better than 0.8″and 75% better than 1.5″. The experiment shows that the DIMM exposure time has significant effects on the results of seeing measurements. An SBIG Polaris seeing monitor, which had been planned to be installed on the LAMOST site for long-term monitoring, was also employed during the DIMM observations. The results show that the SBIG seeing monitor is easily affected by gusty wind, resulting in larger seeing values. Considering the previous seeing measurements at Xinglong station over the last 15 yr, we conclude that an acceptable seeing condition at Xinglong station is around 1″-2″.

关键词： techniques atmospheric turbulence seeing -- instrumentation DIMM -- site testing LAMOST

Site testing campaign for the Large Optical Telescope at the Ali site

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Research in Astronomy and Astrophysics 2020年第6期20卷 141-150页

作者： Li-yong Liu yong-qiang yao Jia Yin Hong-Shuai Wang Jun-Rong Li Yun-He Zhou Xian-Long You Peng Tang Xi-Yue Zhao De-qiang Ma Jian Dong National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The Large Optical/infrared Telescope(LOT)is a ground-based 12 m diameter telescope which is proposed to be built in western *** site selection for LOT in China began in 2016,and Ali was listed as one of the three candidate *** studies and local surveys have been carried out for more than 15 years in western China,and the results show that Ali is a promising site with comprehensive quality in terms of atmospheric and supporting *** overview of the site testing campaign at the Ali site from 2016 to 2019 is *** the two years of data collection,the overall median seeing value is found to be 1.17 arcsec,the observable nights are 81.71%and the good observable nights are 71.76%.The weather conditions as follows,the median night temperature value is-5.18℃,the median night relative humidity value is 41.25%,the median night atmospheric pressure value is 540.92 hPa,the median night wind speed value is 7.41 m s-1 and the mainly wind direction is southwestern(SW).The median night sky background value is 22.07 *** also discuss the wind speed at different locations on-site,the possibility of light pollution and the effect of wind speed on differential image motion monitor(DIMM)seeing measurements.

关键词： large optical telescope site testing Ali site cloudiness seeing

LAMOST MRS-N Observation of the W80 Region

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Research in Astronomy and Astrophysics 2022年第7期22卷 161-175页

作者： yao Li Chao-Jian Wu yong-qiang yao Wei Zhang Jia Yin Juan-Juan Ren Chih-Hao Hsia Rui Zhuang Jian-Jun Chen Yu-Zhong Wu Hui Zhu Bin Li yong-Hui Hou Meng-Yuan yao Hong Wu National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyTaipaMacaoChina University of Science and Technology Beijing Beijing 100083China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008China University of Science and Technology of China Hefei 230026China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China China Academy of Aerospace Electronics Technology Beijing 100094China

The spectral observations and analysis for the W80 region are presented by using the data of Medium-Resolution Spectroscopic Survey of Nebulae(MRS-N) with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST).A total of 2982 high-quality nebular spectra have been obtained in the 20 square degree field of view which covers the W80 complex,and the largest sample of spectral data has been established for the first *** relative intensities,radial velocities(RVs),and full widths at half maximum(FWHMs) are measured with the high spectral resolution of LAMOST MRS-N,for Ha λ6563?,[NⅡ] λλ6548 A,6584 A,and [SⅡ] λλ6716A,6731 A emission *** the field of view of the whole W80 region,the strongest line emissions are found to be consistent with the bright nebulae NGC 7000,IC 5070,and LBN 391,and weak line emissions also exist in the Middle Region,where no bright nebulae are detected by the wide-band optical *** large-scale spectral observations of the W80 region reveal the systematic spatial variations of RVs and FWHMs,and several unique structural features.A "curved feature" to the east of NGC 7000,and a "jet feature" to the west of LBN 391 are detected to be showing larger RVs.A "wider FWHM region" is identified in the eastern part of NGC *** variations of[S Ⅱ]/Ha ratios display a gradient from southwest to northeast in the NGC 7000 region,and manifest a ring shape around the "W80 bubble" ionized by an O-type star in *** spectral and multi-band observations are guaranteed to investigate in detail the structural features.

关键词： surveys (ISM:)HII regions ISM:molecules ISM:bubbles methods:statistical

Probing primordial gravitational waves: Ali CMB Polarization Telescope

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National Science Review 2019年第1期6卷 145-154页

作者： Hong Li Si-Yu Li Yang Liu yong-Ping Li Yifu Cai Mingzhe Li Gong-Bo Zhao Cong-Zhan Liu Zheng-Wei Li He Xu Di Wu yong-Jie Zhang Zu-Hui Fan yong-qiang yao Chao-Lin Kuo Fang-Jun Lu Xinmin Zhang Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Theoretical Physics Division Institute of High Energy PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences CAS Key Laboratory for Researches in Galaxies and Cosmology Department of AstronomyUniversity of Scienceand Technology of China Interdisciplinary Center for Theoretical Study University of Science and Technology of China National Astronomical Observatories Chinese Academy of Sciences Institute of Cosmology& Gravitation University of Portsmouth Key Laboratory of Particle Astrophysics Institute of High EnergyPhysics Chinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics ChineseAcademy of Sciences Department of Astronomy School of Physics Peking University Physics Department Stanford University

In this paper, we will give a general introduction to the Ali CMB Polarization Telescope(Ali CPT) project,which is a Sino–US joint project led by the Institute of High Energy Physics and involves many different institutes in China. It is the first ground-based Cosmic Microwave Background(CMB) polarization experiment in China and an integral part of China’s Gravitational-wave Program. The main scientific goal of the Ali CPT project is to probe the primordial gravitational waves(PGWs) originating from the very early Universe. The AliCPT project includes two stages. The first stage, referred to as AliCPT-1, is to build a telescope in the Ali region of Tibet at an altitude of 5250 meters. Once completed, it will be the highest ground-based CMB observatory in the world and will open a new window for probing PGWs in the northern hemisphere. The AliCPT-1 telescope is designed to have about 7000 transition-edge sensor detectors at 95 GHz and 150 GHz. The second stage is to have a more sensitive telescope(Ali CPT-2) with more than 20 000 detectors. Our simulations show that AliCPT will improve the current constraint on the tensor-to-scalar ratio r by one order of magnitude with three years’ observation. Besides the PGWs, Ali CPT will also enable a precise measurement of the CMB rotation angle and provide a precise test of the CPT symmetry. We show that three years’ observation will improve the current limit by two orders of magnitude.

关键词： primordial gravitational waves cosmic microwave background Ali CMB Polarization Telescope

Site-testing at Muztagh-ata site Ⅰ:ground meteorology and sky brightness

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Research in Astronomy and Astrophysics 2020年第6期20卷 162-174页

作者： Jing Xu Ali Esamdin Jin-Xin Hao Jin-Min Bai Ji Yang Xu Zhou yong-qiang yao Jin-Liang Hou Guang-Xin Pu Guo-Jie Feng Chun-Hai Bai Peng Wei Shu-Guo Ma Abudusaimaitijiang Yisikandee Le-Tian Wang Xuan Zhang Liang Ming Lu Ma Jin-Zhong Liu Zi-Huang Cao yong-Heng Zhao Lu Feng Jian-Rong Shi Hua-Lin Chen Chong Pei Xiao-Jun Jiang Jian-Feng Wang Jian-Feng Tian Yan-Jie Xue Jing-yao Hu Yun-Ying Jiang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Yunnan Observatories Chinese Academy of SciencesKunming 650000China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008 China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210008China

Site-testing is crucial for achieving the goal of scientific research and analysis of meteorological and optical observing conditions,one of the associated basic *** one of three potential sites to host the 12-meter Large Optical/infrared Telescope(LOT),the Muztagh-ata site,which is located on the Pamir Plateau in Xinjiang,in west China,began its site-testing task in the spring of *** this paper,we firstly start with an introduction to the site and then present a statistical analysis of the ground-level meteorological properties such as air temperature,barometric pressure,relative humidity,and wind speed and direction,recorded by an automatic weather station with standard meteorological sensors for a two-year *** also show the monitoring results of sky brightness during this period.

关键词： site testing meteorological condition optical observing

Site testing at Muztagh-ata site Ⅱ:seeing statistics

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Research in Astronomy and Astrophysics 2020年第6期20卷 175-184页

作者： Jing Xu Ali Esamdin Jin-Xin Hao Jin-Min Bai Ji Yang Xu Zhou yong-qiang yao Jin-Liang Hou Guang-Xin Pu Guo-Jie Feng Chun-Hai Bai Peng Wei Shu-Guo Ma Abudusaimaitijiang Yisikandee Le-Tian Wang Xuan Zhang Liang Ming Lu Ma Jin-Zhong Liu Zi-Huang Cao yong-Heng Zhao Lu Feng Jian-Rong Shi Hua-Lin Chen Chong Pei Xiao-Jun Jiang Jian-Feng Wang Jian-Feng Tian Yan-Jie Xue Jing-yao Hu Yun-Ying Jiang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Yun nan Observatories Chin ese Academy of Scie ncesKun ming 650000China Purple Mountain Observatory Chinese Academy of SciencesNanjing 21000&China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210008China

In this article,we present a detailed analysis of the statistical properties of seeing for the Muztaghata site which is a candidate site for hosting the future Chinese Large Optical/infrared Telescope(LOT)*** measurements were obtained with differential image motion monitors(DIMMs)from April2017 to November 2018 at different heights during different *** median seeings at 11 m and6 m are very close but significantly different from that on the *** mainly analyzed the seeing at11 m monthly and hourly,having found that the best season for observing was from late autumn to early winter and seeing tended to improve during the night only in *** analysis of the dependence on temperature inversion,wind speed and direction also was made and the best meteorological conditions for seeing are given.

关键词： site testing seeing

Site testing campaign for the Large Optical/infrared Telescope of China:overview

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Research in Astronomy and Astrophysics 2020年第6期20卷 81-95页

作者： Lu Feng Jin-Xin Hao Zi-Huang Cao Jin-Min Bai Ji Yang Xu Zhou yong-qiang yao Jin-Liang Hou yong-Heng Zhao Yu Liu Teng-Fei Song Li-yong Liu Jia Yin Hua-Lin Chen Chong Pei Ali Esamdin Lu Ma Chun-Hai Bai Peng Wei Jing Xu Guang-Xin Pu Guo-Jie Feng Xuan Zhang Liang Ming Abudusaimaitijiang Yisikandee Jian-Rong Shi Jian Li Yuan Tian Zheng Wang Xia Wang Xiao-Jun Jiang Jian-Feng Wang Jian-Feng Tian Yan-Jie Xue Jian-Sheng Chen Jing-yao Hu Zhi-Xia Shen Yun-Ying Jiang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210033China University of Chinese Academy of Sciences Beijing 100049China

The Large Optical/infrared Telescope(LOT)is a ground-based 12 m diameter optical/infrared telescope which is proposed to be built in the western part of China in the next *** on satellite remote sensing data,along with geographical,logistical and political considerations,three candidate sites were chosen for ground-based astronomical performance *** sites include:Ali in Tibet,Daocheng in Sichuan and Muztagh-ata in *** until now,all three sites have continuously collected data for two *** this paper,we will introduce this site testing campaign,and present its monitoring results obtained during the period between March 2017 and March 2019.

关键词： techniques telescope-site testing

Long-term analysis of clear nights using satellite data considering astronomical sites in western China

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Research in Astronomy and Astrophysics 2020年第6期20卷 96-108页

作者： Zi-Huang Cao Li-yong Liu yong-Heng Zhao Lu Feng Hugh RAJones Huang Shen Jin-Xin Hao Yan-Jie Xue yong-qiang yao Jing Xu Ali Esamdin Zhao-Xiang Qi Jian-Rong Shi Jian Li Yuan Tian Zheng Wang Tai-Sheng Yan Xia Wang Jian-Ping Xiong Si-Cheng Yu Jun-Bo Zhang Zhi-Xia Shen Yun-Ying Jiang Jia Yin Guang-Xin Pu Peng Wei Chun-Hai Bai Guo-Jie Feng Lu Ma Teng-Fei Song Jian-Feng Wang Jian-Feng Tian Xian-Qun Zeng Zhi-Gang Hou Shi-Long Liao Zhi-Song Cao Dong-Wei Fan Yun-Fei Xu Chang-Hua Li Yi-Han Tao National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Centre for Astrophysics University of HertfordshireHatfieldUK School of Journalism.Communication University of China Beijing 100024China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

A large ground-based optical/infrared telescope is being planned for a world-class astronomical site in *** cloud-free night percentage is the primary meteorological consideration for evaluating candidate *** data from GMS and NOAA satellites and the MODIS instrument were utilized in this research,covering the period from 1996 to *** data analysis benefits from overlapping results from different independent teams as well as a uniform analysis of selected sites using GMS+NOAA *** significant ground-based monitoring is needed to validate these findings,we identify three different geographical regions with a high percentage of cloud-free conditions(~83%on average),which is slightly lower than at Mauna Kea and Cerro Armazones(~85%on average)and were chosen for the large international projects TMT and ELT *** study finds evidence that cloud distributions and the seasonal changes affected by the prevailing westerly winds and summer monsoons reduce the cloud cover in areas influenced by the *** is consistent with the expectations from climate change models and is suggestive that most of the identified sites will have reduced cloud cover in the future.

关键词： methods statistical-site testing-atmospheric effects-MODIS

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直驱式自定心中心架的设计与仿真分析

机械设计 2016年第9期33卷 51-55页

作者：赵永强王耀锋侯红玲陕西理工大学机械工程学院陕西汉中723000

自定心中心架用于细长轴类工件(尤其是丝杠、螺杆等工件)机械加工时进行辅助支承,其夹持工件的定心精度直接影响零件本身的加工精度。文中介绍了一种直驱式自定心中心架的设计过程,建立了自定心中心架精确几何模型,给出了片状凸轮的结... 详细信息

自定心中心架用于细长轴类工件(尤其是丝杠、螺杆等工件)机械加工时进行辅助支承,其夹持工件的定心精度直接影响零件本身的加工精度。文中介绍了一种直驱式自定心中心架的设计过程,建立了自定心中心架精确几何模型,给出了片状凸轮的结构及凸轮廓型的精确计算过程,设计了一种自定心中心架定位精度的验算方法,利用三维软件建立了自定心中心架的结构模型,仿真了夹持不同直径工件时定位精度,验证了自定心中心架的设计和凸轮廓型计算的准确性,为高精度自定心中心架的设计提供了理论依据。

关键词：自定心中心架凸轮廓型细长轴加工