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STAR-HD电成像极板国产化改进及应用
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作者 闫明琦 刘李春 +3 位作者 党益伟 王辉 王康 杜康 《国外测井技术》 2024年第6期38-44,共7页
本文着重探讨STAR-HD电成像极板国产化的改进过程。通过对国内外电成像技术的对比分析,突显国产化改进的紧迫性和重要性。本文详细介绍了实验材料与设备的选择,对极板材料进行了深入分析,并对极板电路进行了改造与优化设计。在极板结构... 本文着重探讨STAR-HD电成像极板国产化的改进过程。通过对国内外电成像技术的对比分析,突显国产化改进的紧迫性和重要性。本文详细介绍了实验材料与设备的选择,对极板材料进行了深入分析,并对极板电路进行了改造与优化设计。在极板结构改进上,详述了极板改进的承压实验详细数据,以及数据采集与处理的科学方法。通过严谨的实验过程,本研究得到了极板性能的测试结果,并对比分析了改进前后的差异,凸显了国产化改进的有效性。文章最后总结了实验结果,指出了国产极板在技术上的提升,以及在电成像领域应用的前景与价值。 展开更多
关键词 star-hd 电成像极板 极板电路优化 承压结构 信号线
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基于改进的HD距离的星图识别算法 被引量:1
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作者 陈艳平 王广君 《天文研究与技术》 CSCD 北大核心 2007年第2期159-162,共4页
在基于星敏感器的航天飞行器的自主天文导航中,星图识别是关键技术之一。将改进的HD距离算法用于星图识别,避免了由于个别星体出现较大噪声,以及流星等干扰星出现时发生误匹配的问题。在匹配时利用了星图的全部空间结构信息,具有强的抗... 在基于星敏感器的航天飞行器的自主天文导航中,星图识别是关键技术之一。将改进的HD距离算法用于星图识别,避免了由于个别星体出现较大噪声,以及流星等干扰星出现时发生误匹配的问题。在匹配时利用了星图的全部空间结构信息,具有强的抗星敏感器畸变、噪声和旋转能力,同时也不需要复杂的特征提取算法。仿真实验显示它具有较高的实用价值。 展开更多
关键词 天文导航 星敏感器 星图识别 HD距离
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A likely candidate of type Ia supernova progenitors: the X-ray pulsating companion of the hot subdwarf HD 49798
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作者 Bo Wang Zhan-Wen Han 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2010年第7期681-688,共8页
HD 49798 is a hydrogen depleted subdwarf 06 star and has an X-ray pulsating companion (RX J0648.0-4418). The X-ray pulsating companion is a massive white dwarf. Employing Eggleton's stellar evolution code with the ... HD 49798 is a hydrogen depleted subdwarf 06 star and has an X-ray pulsating companion (RX J0648.0-4418). The X-ray pulsating companion is a massive white dwarf. Employing Eggleton's stellar evolution code with the optically thick wind assumption, we find that the hot subdwarf HD 49798 and its X-ray pulsating companion could produce a type Ia supernova (SN Ia) in future evolution. This implies that the binary system is a likely candidate of an SN Ia progenitor. We also discuss the possibilities of some other WD + He star systems (e.g. V445 Pup and KPD 1930+2752) for producing SNe Ia. 展开更多
关键词 binaries close -- stars individual (HD 49798) -- stars evolution -- supernovae general -- white dwarfs
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Variability of emission lines in the optical spectra of the Herbig Be binary system HD 200775
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作者 Anastasia P.Bisyarina ANDrey M.Sobolev +1 位作者 Stanislav Yu.Gorda Anatoly S.Miroshnichenko 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第3期31-34,共4页
In our previous papers we have improved the value of the orbital period of the binary Herbig Be star HD 200775 and showed that the [O I] and Si II 6347 and 6371 ?A emission lines displayed variations which correlate w... In our previous papers we have improved the value of the orbital period of the binary Herbig Be star HD 200775 and showed that the [O I] and Si II 6347 and 6371 ?A emission lines displayed variations which correlate with the orbital period. In this paper we provide evidences that other broad emission lines of metals in the spectra of HD 200775 also exhibit variability, which is probably related to the orbital cycle of the binary. Analysis was performed based on the high-resolution spectral data collected over a time span of 6 years at the Kourovka Astronomical Observatory of the Ural Federal University(Russia) and the Three College Observatory of the University of North Carolina at Greensboro(USA) as well as archival spectral data compiled since 1994. We report new data points in the radial velocity curve of the He I 5876 ?A line near the extremal values of the radial velocity. 展开更多
关键词 techniques spectroscopic-stars variables T Tauri Herbig Ae/Be-stars individual HD 200775
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Three-dimensional orbit and physical parameters of HD 6840
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作者 Xiao-Li Wang Shu-Lin Ren Yan-Ning Fu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第2期113-118,共6页
HD 6840 is a double-lined visual binary with an orbital period of N7.5 years. By fitting the speckle interferometric measurements made by the 6 m BTA telescope and 3.5 m WIYN telescope, Balega et al. gave a preliminar... HD 6840 is a double-lined visual binary with an orbital period of N7.5 years. By fitting the speckle interferometric measurements made by the 6 m BTA telescope and 3.5 m WIYN telescope, Balega et al. gave a preliminary astrometric orbital solution of the system in 2006. Recently, Griffin derived a precise spectroscopic orbital solution from radial velocities observed with OPH and Cambridge Coravel. However, due to the low precision of the determined orbital inclination, the derived component masses are not satisfying. By adding the newly collected astrometric data in the Fourth Catalog of Interferometric Measurements of Binary Stars, we give a three-dimensional orbit solution with high precision and derive the preliminary physical parameters of HD 6840 via a simultaneous fit including both astrometric and radial velocity measurements. 展开更多
关键词 BINARIES spectroscopic -- astrometry -- stars fundamental parameters -- stars individual (HD 6840)
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Hα profile variations in the spectrum of the supergiant HD14134
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作者 Yanosh Mahmud Maharramov Gunel Osman Jahangirova 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第4期67-80,共14页
Variations of the Ha line in the spectra of the star HD14134 are investigated using ob- servations carried out in 2013-2014 and in 2016 with the 2-m telescope at Shamakhy Astrophysical Observatory. In the spectra of t... Variations of the Ha line in the spectra of the star HD14134 are investigated using ob- servations carried out in 2013-2014 and in 2016 with the 2-m telescope at Shamakhy Astrophysical Observatory. In the spectra of this star, the absorption and emission components of Hα are found to disappear and an inverse P Cyg profile of Ha is seen on some observational epochs. Our observations showed that when the Ha line disappeared or an inversion of the P-Cyg-type profile is observed in the spectra, the Hβ line is redshifted. When these events appeared, no synchronous variabilities were ob- served in the spectral parameters of other spectral lines formed in deeper atmospheric layers. In addition, the structures of Ha, CII (6578.05A, 6582.88A), Sill (6347.1 A, 6371.36A) and Hβ lines are variable on a timescale of hours, but we did not detect significant variations in the other photospheric lines, as well as in the HeI (5875.72A) line. It is suggested that observational evidence for the non-stationary atmosphere of HD 14134 can be associated in part with non-spherical stellar wind. 展开更多
关键词 star: HD 14134 -- supergiant -- wind -- outflow
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A possible substellar companion to the intermediate-mass giant HD 175679
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作者 Liang Wang Bun'ei Sato +12 位作者 Gang Zhao Yu-Juan Liu Kunio Noguchi Hirovasu Ando Hideyuki Izumiura Eiji Kambe Masashi Omiya Hiroki Harakawa Fan Liu Xiao-Shu Wu Yoichi Takeda Michitoshi Yoshida Eiichiro Kokubo 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第1期84-92,共9页
We report the discovery of a substellar companion around the intermediate- mass giant HD 175679. Precise radial velocity data of the star from the Xinglong Station and the Okayama Astrophysical Observatory revealed a ... We report the discovery of a substellar companion around the intermediate- mass giant HD 175679. Precise radial velocity data of the star from the Xinglong Station and the Okayama Astrophysical Observatory revealed a Keplerian velocity variation with an orbital period of 1366.8±5.7 d, a semiamplitude of 380.2±3.2 m s-1 and an eccentricity of 0.378± 0.008. Adopting a stellar mass of 2.7± 0.3 M, we obtain that the minimum mass of the HD 175679 b is 37.3± 2.8 M and the semimajor axis is 3.36±0.12 AU. This discovery is the second brown dwarf companion candidate from a joint planet-search program between China and Japan. 展开更多
关键词 stars: individual (HD 175679) -- stars: brown dwarfs -- techniques:radial velocities
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Exploring the sources of p-mode frequency shifts in the CoRoT target HD 49933
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作者 Zhi-E Liu Shao-Lan Bi +5 位作者 Wu-Ming Yang Tan-Da Li Kang Liu Zhi-Jia Tian Zhi-Shuai Ge Jie Yu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第6期683-692,共10页
Oscillations of the solar-like star HD 49933 have been thoroughly observed by CoRot. Two dozen frequency shifts, which are closely related to the change in magnetic activity, have been measured. To explore the effects... Oscillations of the solar-like star HD 49933 have been thoroughly observed by CoRot. Two dozen frequency shifts, which are closely related to the change in magnetic activity, have been measured. To explore the effects of magnetic activity on frequency shifts, we calculate frequency shifts for the radial and l=1 p-modes of HD 49933 with the general variational method, which evaluates the shifts using a spa- tial integral of the product of a kernel and some sources. The theoretical frequency shifts reproduce the observation well. The magnitudes and positions of the sources are determined according to a χ2 criterion. We predict the source that contributes to both the l = 0 and l= 1 modes is located 0.48 - 0.62 Mm below the surface of the star. In addition, based on the assumption that A0 is proportional to the change in the MglI activity index △iMgⅡ, we obtain that the change in MgⅡ index between the minimum and maximum of the cycle during the period of HD 49933 is about 0.665. The magnitude of the frequency shifts compared to the Sun already demonstrates that HD 49933 is much more active than the Sun, which is further confirmed in this pa- per. Furthermore, our calculation of the frequency shifts for l = 1 modes indicates the variation of turbulent velocity in the stellar convective zone may be an important source for the l = 1 shifts. 展开更多
关键词 stars: individual (HD 49933) -- stars: evolution -- stars: oscillation --stars: modeling
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The ROSAT bright source 1RXS J201607.0+251645:an active Algol-type binary
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作者 Hua-Li Li Yuan-Gui Yang +2 位作者 Wei Su Hui-Juan Wang Jian-Yan Wei 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2009年第9期1035-1048,共14页
1RXS J201607.0+251645 is identified as an eclipsing binary. We present preliminary observations in the V band with the 0.6-m telescope for three years and extensive observations in the V and R bands with the 0.8-m te... 1RXS J201607.0+251645 is identified as an eclipsing binary. We present preliminary observations in the V band with the 0.6-m telescope for three years and extensive observations in the V and R bands with the 0.8-m telescope for six nights, respectively. The light curve of the system is E13 type. Five light minimum times were obtained and the orbital period of 0.388058^d(±0.00044d) is determined. The photometric solution given by the 2003-version of the Wilson-Devinney program suggests that the binary is a semidetached system with photometric mass ratio 0.895(±0.006), which is probably comprised of a G5 primary and an oversized K5 secondary. The tess massive component has completely filled its Roche lobe, while the other one almost fills its Roche lobe with a filling factor of 93.4%. The system shows a varying O'Connell effect in its phase folded diagrams from 2005 to 2007, and is X-ray luminous with log Lx/Lbol - -3.27. Possible mechanisms to account for these two phenomena are discussed. Finally, we infer that the binary may be in thermal oscillation or may evolve into a contact binary. 展开更多
关键词 stars: binaries: close -- stars: binaries: eclipsing -- stars: individual: 1RXSJ201607.0+251645 HD 339946
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Photometric observations of three high mass X-ray binaries and a search for variations induced by orbital motion
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作者 Gordon E. Sarty Bogumil Pilecki +8 位作者 Daniel E. Reichart Kevin M. Ivarsen Joshua B. Haislip Melissa C. Nysewander Aaron P. LaCluyze Helen M. Johnston Robert R. Shobbrook Lászl L. Kiss Kinwah Wu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第8期947-964,共18页
We searched for long period variation in V-band, It-band and RXTE X-ray light curves of the High Mass X-ray Binaries (HMXBs) LS 1698 / RX J1037.5-5647, HD 110432 / 1H 1249-637 and HD 161103 / RX J1744.7-2713 in an a... We searched for long period variation in V-band, It-band and RXTE X-ray light curves of the High Mass X-ray Binaries (HMXBs) LS 1698 / RX J1037.5-5647, HD 110432 / 1H 1249-637 and HD 161103 / RX J1744.7-2713 in an attempt to discover orbitally induced variation. Data were obtained primarily from the ASAS database and were supplemented by shorter term observations made with the 24- and 40-inch ANU telescopes and one of the robotic PROMPT telescopes. Fourier periodograms suggested the existence of long period variation in the V-band light curves of all three HMXBs, however folding the data at those periods did not reveal convincing periodic variation. At this point we cannot rule out the existence of long term V-band variation for these three sources and hints of longer term variation may be seen in the higher precision PROMPT data. Long term V-band observations, on the order of several years, taken at a frequency of at least once per week and with a precision of 0.01 mag, therefore still have a chance of revealing long term variation in these three HMXBs. 展开更多
关键词 accretion -- stars: Be stars -- stars: neutron stars -- stars: individual LS 1698 HD 110432 HD 161103 -- X-rays: binaries
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Time-dependent Behaviour of the Low Amplitudeδ Scuti Star HD 52788
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作者 Ai-YingZhou 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2004年第4期335-342,共8页
Wavelet transform is applied to reanalyze the low amplitude δ Scuti star HD 52788, which exhibits complex light variations with uncertain frequency solutions. We gain an insight into the strong instability of pulsati... Wavelet transform is applied to reanalyze the low amplitude δ Scuti star HD 52788, which exhibits complex light variations with uncertain frequency solutions. We gain an insight into the strong instability of pulsation present in the star. Based on an estimate of the star's physical parameters, its evolutionary status is determined. An attempt of asteroseismic modelling failed to predict the observed dense frequencies. Because of its varying pulsation spectrum, HD 52788 is a distinctive and very interesting object among δ Sct stars for testing current models of stellar evolution and pulsation. 展开更多
关键词 methods: data analysis - stars: oscillations - δScuti - stars:individual (HD 52788)
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海康威视智能建筑安防综合解决方案解析
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作者 张沛 《智能建筑》 2014年第10期64-66,80,共4页
根据智能建筑行业和安防技术发展的新趋势,海康威视前瞻性地提出了智能建筑安防综合解决方案,并提出大集成"七星"价值体验。同时,该解决方案通过与各类建筑体的业态和场景特征巧妙结合,分别衍生出住宅、综合体、酒店、写字楼... 根据智能建筑行业和安防技术发展的新趋势,海康威视前瞻性地提出了智能建筑安防综合解决方案,并提出大集成"七星"价值体验。同时,该解决方案通过与各类建筑体的业态和场景特征巧妙结合,分别衍生出住宅、综合体、酒店、写字楼、工地五大业态化安防建设应用方案。 展开更多
关键词 安防综合解决方案 大集成与综合管理 “七星”价值体验 高清监控 业态化
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