共查询到20条相似文献，搜索用时 937 毫秒
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Based on published data, we have collected information about Galactic maser sources with measured distances. In particular, 44 Galactic maser sources located in star-forming regions have trigonometric parallaxes, proper motions, and radial velocities. In addition, ten more radio sources with incomplete information are known, but their parallaxes have been measured with a high accuracy. For all 54 sources, we have calculated the corrections for the well-known Lutz-Kelker bias. Based on a sample of 44 sources, we have refined the parameters of the Galactic rotation curve. Thus, at R 0 = 8kpc, the peculiar velocity components for the Sun are (U ⊙, V ⊙, W ⊙) = (7.5, 17.6, 8.4) ± (1.2, 1.2, 1.2) km s?1 and the angular velocity components are ω 0 = ?28.7 ± 0.5 km s?1 kpc?1, ω 0′ = +4.17 ± 0.10 km s?1 kpc?2, and ω0″ = ?0.87 ± 0.06 km s?1 kpc?3. The corresponding Oort constants are A = 16.7 ± 0.6 km s?1 kpc?1 and B = ?12.0 ± 1.0 km s?1 kpc?1; the circular rotation velocity of the solar neighborhood around the Galactic center is V 0 = 230 ± 16 km s?1. We have found that the corrections for the Lutz-Kelker bias affect the determination of the angular velocity ω 0 most strongly; their effect on the remaining parameters is statistically insignificant. Within themodel of a two-armed spiral pattern, we have determined the pattern pitch angle $i = - 6_.^ \circ 5$ and the phase of the Sun in the spiral wave χ 0 = 150°. 相似文献
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Three new approximate forms for theH-function for isotropic scattering have been developed. Each of the forms involve three unknown functions of albedo . 相似文献
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Scanning Sky Monitor (SSM) on ASTROSAT is an X-ray sky monitor which has a large Field of View (FOV) and scans the sky to detect and locate X-ray transient sources in the energy range 2 to 10 keV. Experiments are carried out to calibrate SSM detectors for position response and to verify the calibration constants derived. In this paper we discuss the methodology of position calibration of proportional counters for SSM and results from various experiments. 相似文献
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I. M. Nesterin K. M. Pichhadze V. K. Sysoev V. S. Finchenko S. O. Firsyuk A. D. Yudin 《Solar System Research》2018,52(7):606-612
The article discusses proposals for creating a standard unit based on CubeSat technology, an independent autonomous aerobraking device based on inflatable balloons or a solar sail cone section. The proposed devices have a simple start-up system and are an additional component in the CubeSat assembly for deorbiting from low-Earth orbits. 相似文献
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The polarimetric Littrow Spectrograph POLIS is designed for vector polarimetry at high angular and spectral resolution. It measures the magnetic field simultaneously in the photosphere and the chromosphere of the sun. Both branches of the polarimetry unit are dual beam systems with a single rotating modulator for both wavelengths and polarizing beam splitters in front of each CCD camera. POLIS has been installed at the VTT on Tenerife and has seen First Light on 17 May 2002. A modified version of POLIS will be developed for the balloon mission Sunrise . That version will have UV capabilities down to 200 nm. 相似文献
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《中国天文和天体物理学报》2011,(7)
Research in Astronomy and Astrophysics publishes original research papers and reviews on all branches of astronomy and astrophysics.Reviews are by invitation only.Important new results that require rapid publication can be submitted as a Letter(Letters must be restricted in length to 6 printed pages). 相似文献
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《天文和天体物理学研究(英文版)》2013,(7):885
Research in Astronomy and Astrophysics publishes original research papers and reviews on all branches of astronomy and astrophysics. Reviews are by invitation only. Important new results that require rapid publication can be submitted as a Letter (Letters must be restricted in length to 6 printed pages). 相似文献
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《天文和天体物理学研究(英文版)》2013,(6):757
Research in Astronomy and Astrophysics publishes original research papers and reviews on all branches of astronomy and astrophysics. Reviews are by invitation only. Important new results that require rapid publication can be submitted as a Letter (Letters must be restricted in length to 6 printed pages). 相似文献
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《中国天文和天体物理学报》2013,(10):F0003-F0003
Research in branches of that require to 6 printed Astronomy and Astrophysics publishes original research papers and reviews on all astronomy and astrophysics. Reviews are by invitation only. Important new results rapid publication can be submitted as a Letter （Letters must be restricted in length pages）. 相似文献
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《天文和天体物理学研究(英文版)》2017,(12)
<正>Research in Astronomy and Astrophysics publishes original research papers and reviews on all branches of astronomy and astrophysics.Reviews are by invitation only.Important new results that require rapid publication can be submitted as a Letter(Letters must be restricted in length to 6 printed pages). 相似文献
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《天文和天体物理学研究(英文版)》2017,(3)
<正>Research in Astronomy and Astrophysics publishes original research papers and reviews on all branches of astronomy and astrophysics.Reviews are by invitation only.Important new results that require rapid publication can be submitted as a Letter(Letters must be restricted in length to 6 printed pages). 相似文献
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《天文和天体物理学研究(英文版)》2015,(6)
<正>Research in Astronomy and Astrophysics publishes original research papers and reviews on all branches of astronomy and astrophysics.Reviews are by invitation only.Important new results that require rapid publication can be submitted as a Letter(Letters must be restricted in length to 6 printed pages).Authors who submit a paper are expected to be able to certify that the paper is original work.has not been published before and is not being considered for publication elsewhere.By submitting 相似文献
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《天文和天体物理学研究(英文版)》2017,(11)
<正>Research in Astronomy and Astrophysics publishes original research papers and reviews on all branches of astronomy and astrophysics.Reviews are by invitation only.Important new results that require rapid publication can be submitted as a Letter(Letters must be restrictced in length to 6 printed pages). 相似文献
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《天文和天体物理学研究(英文版)》2015,(10)
<正>Research in Astronomy and Astrophysics publishes original research papers and reviews on all branches of astronomy and astrophysics.Reviews are by invitation only.Important new results that require rapid publication can be submitted as a Letter(Letters must be restricted in length to 6 printed pages).Authors who submit a paper are expected to be able to certify that the paper is original work,has not been published before and is not being considered for publication elsewhere.By submitting 相似文献
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