This study analyzes total electron content(TEC)variations during two solar eclipse events that occurred on October 25,2022,and October 14,2023.The solar eclipse of October 25,2022,was a partial solar eclipse,while the...This study analyzes total electron content(TEC)variations during two solar eclipse events that occurred on October 25,2022,and October 14,2023.The solar eclipse of October 25,2022,was a partial solar eclipse,while the eclipse of October 14,2023,was an annular solar eclipse.For this study,the data of eight International GNSS Service(IGS)stations from different eclipse coverage zones are used to analyze TEC variations.It is found that the stations located in the maximum eclipse cover zone exhibited notable decreases in TEC values.The minimum variation of about 11.76%in TEC values is observed at the station situating in about 20 percent eclipse cover zone,while it varies from 22%to 38%at the stations falling in about 60 percent eclipse cover zone.The highest variation in TEC values of about 44%is found at the stations in about 80 percent eclipse cover zone.The time of occurrence of maximum depletion in TEC values at each station is in line with their longitudinal sequence.Atmospheric gravity waves(AGWs)are also observed by performing wavelet analysis on TEC data.The global TEC maps visualize and confirm observed TEC variations,providing spatial and temporal insights into the ionospheric response.This analysis highlights the influence of station location and eclipse coverage on the magnitude and spatial distribution of TEC variations.展开更多
A group of Chinese astronomers detected a weird pulsar that keeps emitting radio beams in long,regular pauses.After years of follow-up observations and careful data analyses,they finally revealed this exotic pulsar in...A group of Chinese astronomers detected a weird pulsar that keeps emitting radio beams in long,regular pauses.After years of follow-up observations and careful data analyses,they finally revealed this exotic pulsar in Science on May 23 as a rare case:it turns out to be eclipsed by a companion,very likely a helium star,with a mass similar to the Sun and in an orbit smaller than the solar radius.展开更多
During the total solar eclipse of 2013 November 3, a fiber-based spectrometer captured the flash spectrum within the wavelength range of 5162–5325Å, with the field-of-view positioned approximately 0.04 R⊙above ...During the total solar eclipse of 2013 November 3, a fiber-based spectrometer captured the flash spectrum within the wavelength range of 5162–5325Å, with the field-of-view positioned approximately 0.04 R⊙above the east limb, near the second-contact point. This placement near the innermost corona, together with the nearby Baily's beads, enabled the detection of emission lines from the photosphere, lower chromosphere, and corona in the same spectral frame. The higher field-of-view made the coronal line Fe XIV 5303Åmore visible, while the reduced intensity of photospheric and lower chromospheric light, caused by terrestrial scattering, also influenced the observed spectrum. Meanwhile, we selected 18 flash emission lines to measure the ratio of the relative line height of the flash emission line to the relative line depth of the corresponding solar absorption line. This ratio serves as a diagnostic of the source function, minimizing opacity effects. Comparison of disk and flash spectra shows that this ratio increases for spectral lines at greater formation heights, being strongest for chromospheric lines(particularly Fe II), moderate for photospheric low-FIP lines, and weakest for photospheric neutral lines. This trend suggests a rising source function with formation height, potentially linked to increasing electron temperatures or influenced by factors observed in flash spectra near active regions as reported in earlier studies.展开更多
We present a comprehensive analysis of BI CVn,an eclipsing overcontact binary system.New BVR photometric observations,combined with available spectroscopic data,were analyzed simultaneously using the Wilson–Devinney ...We present a comprehensive analysis of BI CVn,an eclipsing overcontact binary system.New BVR photometric observations,combined with available spectroscopic data,were analyzed simultaneously using the Wilson–Devinney method to derive the orbital and physical parameters of the system.The resulting stellar parameters are M1=0.58±0.01M⊙,M2=1.42±0.02M⊙,R1=0.88±0.01R⊙,R2=1.31±0.01R⊙,with an orbital separation of a=2.80±0.01R⊙.Based on all available CCD times of minimum light,including both ground-based and T ESS observations,the(O-C)diagram of BI CVn was analyzed.T he orbital period exhibits a long-term decrease at a rate of-2.3239(±0.0001)×10-8 day yr-1,likely due to mass transfer from the more massive to the less massive component.Superimposed on this trend is a cyclic variation with a period of 56.84±0.08 yr,indicative of a light-travel time effect caused by a third body,whose estimated mass is 0.63±0.02M⊙.Using these derived parameters,we modeled the binary’s evolution through non-conservative processes with the Binary Star Evolution code.The evolutionary tracks of the components were examined in multiple parameter planes,leading to an estimated merger timescale of approximately 2.70 Gyr.展开更多
We conducted the first light curve study of the binary star EL Tuc within the Binary Systems of South and North project's framework.The photometric observations were made using standard multiband BVR_cI_c filters ...We conducted the first light curve study of the binary star EL Tuc within the Binary Systems of South and North project's framework.The photometric observations were made using standard multiband BVR_cI_c filters at an observatory in Argentina.We presented a new ephemeris for EL Tuc and a linear fit to the O–C diagram,utilizing our extracted times of minima and additional literature.We employed the PHysics Of Eclipsing BinariEs Python code and the Markov chain Monte Carlo approach for the system's light curve analysis.The target system's light curve solution required a cold starspot on the hotter component.We conclude that EL Tuc is a total contact binary system with a low mass ratio of q=0.172±0.002,an orbital inclination of i=83°.74±0°.40,and a fillout factor of f=53.7%±1.6%.We used the P-a relationship and the Gaia Data Release 3 parallax method to determine the absolute parameters of EL Tuc to compare the precision of our results.This system was classified as W-type based on the mass and effective temperature of the companion stars.The positions of the systems were depicted on the M-L,M-R,T-M,and q-Lratiodiagrams.The relationship between the spectroscopic and photometric mass ratios of binaries was discussed.展开更多
In this paper,new light curves(LCs) of contact eclipsing binary(CEB) systems LX Lyn and V0853 Aur are presented and analyzed by using the 2015 version of the Wilson-Devinney(W-D) code.In order to explain their asymmet...In this paper,new light curves(LCs) of contact eclipsing binary(CEB) systems LX Lyn and V0853 Aur are presented and analyzed by using the 2015 version of the Wilson-Devinney(W-D) code.In order to explain their asymmetric LCs,cool starspots on the components were employed.It is suggested that their fill-out degrees are f=12.0%(LX Lyn) and f=26.3%(V0853 Aur).At the same time,we found that LX Lyn is a W-type eclipsing binary(EB) with an orbital inclination of i=84°.88 and a mass ratio of q=2.31.V0853 Aur is also a W-type CEB with a mass ratio of q=2.77 and an orbital inclination of i= 79°.26.Based on all available times of light minimum,their orbital period changes are studied by using the O-C method.The O-C diagram of LX Lyn reveals a cyclic oscillation with a period of about 14.84 yr and an amplitude of 0.0019 days,which can be explained by the light-travel time effect(LTTE) due to the presence of a third body with a minimum mass of0.06M_⊙.For V0853 Aur,it is discovered that the O-C diagram of the system also shows a cyclic oscillation with a period of 9.64 yr and an amplitude of 0.03365 days.The cyclic oscillation of V0853 Aur can be attributed to the LTTE by means of a third body with a mass no less than 3.77M_⊙.The third body may play an important role in the formation and evolution of these systems.展开更多
目的实现Eclipse 11.0计划系统中计划靶区和辅助轮廓的自动生成。方法使用Auto Hotkey热键脚本语言,编写适用于Eclipse11.0计划系统的轮廓自动生成软件Contour Auto Margin(CAM),该软件由轮廓操作函数、脚本生成可视化和脚本文件操作模...目的实现Eclipse 11.0计划系统中计划靶区和辅助轮廓的自动生成。方法使用Auto Hotkey热键脚本语言,编写适用于Eclipse11.0计划系统的轮廓自动生成软件Contour Auto Margin(CAM),该软件由轮廓操作函数、脚本生成可视化和脚本文件操作模块构成。结果在临床上选取不同病种各10例,调用由CAM创建的模版脚本在计划系统下运行,模版脚本能完成轮廓自动产生及后处理,各病种自动与手动生成轮廓无差别。结论该软件界面友好,功能强大,能快速实现Eclipse11.0计划系统下计划优化前所需轮廓的自动生成,大大节约计划准备时间,提高放射治疗物理师工作效率。展开更多
基金the Global GNSS-TEC data processing has been supported by JSPS KAKENHI Grant Number 16H06286。
文摘This study analyzes total electron content(TEC)variations during two solar eclipse events that occurred on October 25,2022,and October 14,2023.The solar eclipse of October 25,2022,was a partial solar eclipse,while the eclipse of October 14,2023,was an annular solar eclipse.For this study,the data of eight International GNSS Service(IGS)stations from different eclipse coverage zones are used to analyze TEC variations.It is found that the stations located in the maximum eclipse cover zone exhibited notable decreases in TEC values.The minimum variation of about 11.76%in TEC values is observed at the station situating in about 20 percent eclipse cover zone,while it varies from 22%to 38%at the stations falling in about 60 percent eclipse cover zone.The highest variation in TEC values of about 44%is found at the stations in about 80 percent eclipse cover zone.The time of occurrence of maximum depletion in TEC values at each station is in line with their longitudinal sequence.Atmospheric gravity waves(AGWs)are also observed by performing wavelet analysis on TEC data.The global TEC maps visualize and confirm observed TEC variations,providing spatial and temporal insights into the ionospheric response.This analysis highlights the influence of station location and eclipse coverage on the magnitude and spatial distribution of TEC variations.
文摘A group of Chinese astronomers detected a weird pulsar that keeps emitting radio beams in long,regular pauses.After years of follow-up observations and careful data analyses,they finally revealed this exotic pulsar in Science on May 23 as a rare case:it turns out to be eclipsed by a companion,very likely a helium star,with a mass similar to the Sun and in an orbit smaller than the solar radius.
基金supported by the National Natural Science Foundation of China(NSFC)under grant Nos.12473054 and 12127901the Strategic Priority Research Program of the Chinese Academy of Sciences under grant No.XDB0560000+1 种基金Yunnan Key Laboratory of Solar Physics and Space Science under No.202205AG070009Yunnan Fundamental Research Projects under No.202105AC160085.
文摘During the total solar eclipse of 2013 November 3, a fiber-based spectrometer captured the flash spectrum within the wavelength range of 5162–5325Å, with the field-of-view positioned approximately 0.04 R⊙above the east limb, near the second-contact point. This placement near the innermost corona, together with the nearby Baily's beads, enabled the detection of emission lines from the photosphere, lower chromosphere, and corona in the same spectral frame. The higher field-of-view made the coronal line Fe XIV 5303Åmore visible, while the reduced intensity of photospheric and lower chromospheric light, caused by terrestrial scattering, also influenced the observed spectrum. Meanwhile, we selected 18 flash emission lines to measure the ratio of the relative line height of the flash emission line to the relative line depth of the corresponding solar absorption line. This ratio serves as a diagnostic of the source function, minimizing opacity effects. Comparison of disk and flash spectra shows that this ratio increases for spectral lines at greater formation heights, being strongest for chromospheric lines(particularly Fe II), moderate for photospheric low-FIP lines, and weakest for photospheric neutral lines. This trend suggests a rising source function with formation height, potentially linked to increasing electron temperatures or influenced by factors observed in flash spectra near active regions as reported in earlier studies.
基金a project supported by the Scientific and Technological Research Council of Türkiye (TüB?TAK) under grant No.114F166
文摘We present a comprehensive analysis of BI CVn,an eclipsing overcontact binary system.New BVR photometric observations,combined with available spectroscopic data,were analyzed simultaneously using the Wilson–Devinney method to derive the orbital and physical parameters of the system.The resulting stellar parameters are M1=0.58±0.01M⊙,M2=1.42±0.02M⊙,R1=0.88±0.01R⊙,R2=1.31±0.01R⊙,with an orbital separation of a=2.80±0.01R⊙.Based on all available CCD times of minimum light,including both ground-based and T ESS observations,the(O-C)diagram of BI CVn was analyzed.T he orbital period exhibits a long-term decrease at a rate of-2.3239(±0.0001)×10-8 day yr-1,likely due to mass transfer from the more massive to the less massive component.Superimposed on this trend is a cyclic variation with a period of 56.84±0.08 yr,indicative of a light-travel time effect caused by a third body,whose estimated mass is 0.63±0.02M⊙.Using these derived parameters,we modeled the binary’s evolution through non-conservative processes with the Binary Star Evolution code.The evolutionary tracks of the components were examined in multiple parameter planes,leading to an estimated merger timescale of approximately 2.70 Gyr.
文摘We conducted the first light curve study of the binary star EL Tuc within the Binary Systems of South and North project's framework.The photometric observations were made using standard multiband BVR_cI_c filters at an observatory in Argentina.We presented a new ephemeris for EL Tuc and a linear fit to the O–C diagram,utilizing our extracted times of minima and additional literature.We employed the PHysics Of Eclipsing BinariEs Python code and the Markov chain Monte Carlo approach for the system's light curve analysis.The target system's light curve solution required a cold starspot on the hotter component.We conclude that EL Tuc is a total contact binary system with a low mass ratio of q=0.172±0.002,an orbital inclination of i=83°.74±0°.40,and a fillout factor of f=53.7%±1.6%.We used the P-a relationship and the Gaia Data Release 3 parallax method to determine the absolute parameters of EL Tuc to compare the precision of our results.This system was classified as W-type based on the mass and effective temperature of the companion stars.The positions of the systems were depicted on the M-L,M-R,T-M,and q-Lratiodiagrams.The relationship between the spectroscopic and photometric mass ratios of binaries was discussed.
基金partly supported by the Joint Research Fund in Astronomy (grant Nos. U1931101, 42364001) under cooperative agreement between the National Natural Science Foundation of China (NSFC) and Chinese Academy of Sciences (CAS)the National Natural Science Foundation of China (NSFC, Grant No. 11933008)+3 种基金the Guizhou Provincial Science and Technology Foundation (grant Nos.[2020]1Y017, ZK[2022]322)the Foundation of Education Bureau of Guizhou Province,China (grant No. KY (2020) 003)partially supported by the Open Project Program of the CAS Key Laboratory of Optical Astronomy,National Astronomical Observatories,Chinese Academy of Sciencesthe TESS team for its support。
文摘In this paper,new light curves(LCs) of contact eclipsing binary(CEB) systems LX Lyn and V0853 Aur are presented and analyzed by using the 2015 version of the Wilson-Devinney(W-D) code.In order to explain their asymmetric LCs,cool starspots on the components were employed.It is suggested that their fill-out degrees are f=12.0%(LX Lyn) and f=26.3%(V0853 Aur).At the same time,we found that LX Lyn is a W-type eclipsing binary(EB) with an orbital inclination of i=84°.88 and a mass ratio of q=2.31.V0853 Aur is also a W-type CEB with a mass ratio of q=2.77 and an orbital inclination of i= 79°.26.Based on all available times of light minimum,their orbital period changes are studied by using the O-C method.The O-C diagram of LX Lyn reveals a cyclic oscillation with a period of about 14.84 yr and an amplitude of 0.0019 days,which can be explained by the light-travel time effect(LTTE) due to the presence of a third body with a minimum mass of0.06M_⊙.For V0853 Aur,it is discovered that the O-C diagram of the system also shows a cyclic oscillation with a period of 9.64 yr and an amplitude of 0.03365 days.The cyclic oscillation of V0853 Aur can be attributed to the LTTE by means of a third body with a mass no less than 3.77M_⊙.The third body may play an important role in the formation and evolution of these systems.
文摘目的实现Eclipse 11.0计划系统中计划靶区和辅助轮廓的自动生成。方法使用Auto Hotkey热键脚本语言,编写适用于Eclipse11.0计划系统的轮廓自动生成软件Contour Auto Margin(CAM),该软件由轮廓操作函数、脚本生成可视化和脚本文件操作模块构成。结果在临床上选取不同病种各10例,调用由CAM创建的模版脚本在计划系统下运行,模版脚本能完成轮廓自动产生及后处理,各病种自动与手动生成轮廓无差别。结论该软件界面友好,功能强大,能快速实现Eclipse11.0计划系统下计划优化前所需轮廓的自动生成,大大节约计划准备时间,提高放射治疗物理师工作效率。