Abstract The paper presents study the 11-year dynamics of solar activity on the basis of new observational material on coronal holes (CHs) and sunspots in the period from May 13, 2010 to May 13, 2021. We used the Heliophysics Event Knowledgebase (HEK) to obtain information on CHs areas. For 11 years of observations, we processed about 18000 CHs. Slightly more than 8000 are polar, the rest are nonpolar CHs. The statistical volume of the presented material is quite extensive and gives grounds for the study of the dynamics of different types of CHs during the cycle. Our research has shown: in the 24th solar activity cycle, the South led for polar CHs and the North led for nonpolar ones. We established a relationship between the number and area of CHs and the phase of the solar cycle. The number and daily total area of polar CHs increases at the minima of solar activity and decreases at the maximum of the cycle. This is consistent with the general concept of polar CHs as the main source of the solar dipole magnetic field. An asymmetry in both the number and areas of polar coronal holes in the northern and southern hemispheres is observed. It is shown that the areas of nonpolar CHs change quasi-synchronously with sunspot activity, which suggests a physical connection between these two phenomena.
{"title":"11-year dynamics of coronal hole and sunspot areas","authors":"O. Andreeva, V. Abramenko, V. Malashchuk","doi":"10.1515/astro-2022-0005","DOIUrl":"https://doi.org/10.1515/astro-2022-0005","url":null,"abstract":"Abstract The paper presents study the 11-year dynamics of solar activity on the basis of new observational material on coronal holes (CHs) and sunspots in the period from May 13, 2010 to May 13, 2021. We used the Heliophysics Event Knowledgebase (HEK) to obtain information on CHs areas. For 11 years of observations, we processed about 18000 CHs. Slightly more than 8000 are polar, the rest are nonpolar CHs. The statistical volume of the presented material is quite extensive and gives grounds for the study of the dynamics of different types of CHs during the cycle. Our research has shown: in the 24th solar activity cycle, the South led for polar CHs and the North led for nonpolar ones. We established a relationship between the number and area of CHs and the phase of the solar cycle. The number and daily total area of polar CHs increases at the minima of solar activity and decreases at the maximum of the cycle. This is consistent with the general concept of polar CHs as the main source of the solar dipole magnetic field. An asymmetry in both the number and areas of polar coronal holes in the northern and southern hemispheres is observed. It is shown that the areas of nonpolar CHs change quasi-synchronously with sunspot activity, which suggests a physical connection between these two phenomena.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"22 - 26"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44767995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kanrong Liu, Yajie Wang, Baohui Zhang, Hu Liu, Xu Wang, Bin Wei
Abstract This study presented a mathematical description of an arbitrary shape area, and after analyzing the characteristics of the near-polar orbital co-ground trajectory constellation that satisfies the revisit interval constraint, an optimization model of the orbital parameters design of reference satellites in regional coverage constellations was constructed. Then based on the designed area covering the constellation of common ground trajectories, a simple and effective two-pulse maneuvering scheme was adopted for the needs of sudden tasks, and an existing satellite scheduling optimization model using the golden section method to constrain the boundary of substellar point coverage was constructed. Finally, the optimal design of regional coverage constellations and existing satellite dispatches was carried out for the sea areas with the most frequent tropical cyclone activities in the northwest Pacific Ocean, and the simulation results verified the effectiveness of the proposed optimization model and have certain practical use value.
{"title":"Optimization of satellite resource scheduling under regional target coverage conditions","authors":"Kanrong Liu, Yajie Wang, Baohui Zhang, Hu Liu, Xu Wang, Bin Wei","doi":"10.1515/astro-2022-0036","DOIUrl":"https://doi.org/10.1515/astro-2022-0036","url":null,"abstract":"Abstract This study presented a mathematical description of an arbitrary shape area, and after analyzing the characteristics of the near-polar orbital co-ground trajectory constellation that satisfies the revisit interval constraint, an optimization model of the orbital parameters design of reference satellites in regional coverage constellations was constructed. Then based on the designed area covering the constellation of common ground trajectories, a simple and effective two-pulse maneuvering scheme was adopted for the needs of sudden tasks, and an existing satellite scheduling optimization model using the golden section method to constrain the boundary of substellar point coverage was constructed. Finally, the optimal design of regional coverage constellations and existing satellite dispatches was carried out for the sea areas with the most frequent tropical cyclone activities in the northwest Pacific Ocean, and the simulation results verified the effectiveness of the proposed optimization model and have certain practical use value.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"318 - 326"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46570596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract BeiDou navigation satellite system (BDS) receivers on-board cannot give real-time positioning precision in tracking missile and carrier rocket. In this article, the dynamic filtered optimal estimation theory is applied to the highly dynamic on-board BDS ballistic parameter solution, an optimally constrained geometric dilution precision (GDOP) constellation selection strategy is proposed, a mathematical model based on dynamic filtered estimation for the ballistic determination and precision estimation of the on-board BDS is established, and an analysis of the on-board BDS positioning precision is carried out using the observed data. The calculation results show that the dynamic filter positioning algorithm is simple, practical, and reliable, which can effectively suppress and reduce the random errors of ballistic parameters and significantly improve the positioning precision, fully satisfying the needs of high dynamic and high precision navigation and positioning users, and has good application prospects.
{"title":"On-board BDS dynamic filtering ballistic determination and precision evaluation","authors":"Shuyang Zhao, Jia-Yu Chang","doi":"10.1515/astro-2022-0193","DOIUrl":"https://doi.org/10.1515/astro-2022-0193","url":null,"abstract":"Abstract BeiDou navigation satellite system (BDS) receivers on-board cannot give real-time positioning precision in tracking missile and carrier rocket. In this article, the dynamic filtered optimal estimation theory is applied to the highly dynamic on-board BDS ballistic parameter solution, an optimally constrained geometric dilution precision (GDOP) constellation selection strategy is proposed, a mathematical model based on dynamic filtered estimation for the ballistic determination and precision estimation of the on-board BDS is established, and an analysis of the on-board BDS positioning precision is carried out using the observed data. The calculation results show that the dynamic filter positioning algorithm is simple, practical, and reliable, which can effectively suppress and reduce the random errors of ballistic parameters and significantly improve the positioning precision, fully satisfying the needs of high dynamic and high precision navigation and positioning users, and has good application prospects.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"340 - 347"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48048856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The results of observations of selected stars orbiting the central body of our Galaxy, which, according to the latest data, has a mass of about 4 million of solar mass, are considered. Using the methods of observation and processing of binary stars used at the Pulkovo Observatory and the published exact relative positions of the star-central body obtained with the Keck and VLT telescopes, we checked the possibility of determining the preliminary orbits of the above objects in some cases from observations covering sufficient short arc in relation to the turnover period. Examples are the stars S02 and S102 with published positions and the graphical data for S27 and S4711. We attempted to calculate the assumed relativistic effects in accordance with the orbital elements obtained by Pulkovo methods. In this case, the estimates of the O–C errors for these orbits turned out to be comparable with the O–C errors for the orbits published by the Keck and VLT observers, in some cases about several milliarcseconds. The theoretical relativistic parameters also turned out to be of the same order of value with the results of these authors.
{"title":"Checking the possibility of determining the relative orbits of stars rotating around the center body of the Galaxy","authors":"N. A. Shakht, I. Izmailov, D. Gorshanov","doi":"10.1515/astro-2022-0016","DOIUrl":"https://doi.org/10.1515/astro-2022-0016","url":null,"abstract":"Abstract The results of observations of selected stars orbiting the central body of our Galaxy, which, according to the latest data, has a mass of about 4 million of solar mass, are considered. Using the methods of observation and processing of binary stars used at the Pulkovo Observatory and the published exact relative positions of the star-central body obtained with the Keck and VLT telescopes, we checked the possibility of determining the preliminary orbits of the above objects in some cases from observations covering sufficient short arc in relation to the turnover period. Examples are the stars S02 and S102 with published positions and the graphical data for S27 and S4711. We attempted to calculate the assumed relativistic effects in accordance with the orbital elements obtained by Pulkovo methods. In this case, the estimates of the O–C errors for these orbits turned out to be comparable with the O–C errors for the orbits published by the Keck and VLT observers, in some cases about several milliarcseconds. The theoretical relativistic parameters also turned out to be of the same order of value with the results of these authors.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"136 - 142"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48860738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In this work, cosmological solutions based on the time-dependent cosmological ( Λ Lambda ) and Newtonian ( G G ) running “constants” in the Bianchi type-I spacetime are investigated vis-à-vis known cosmological data. The observationally known values of Ω m , Ω r {Omega }_{{rm{m}}},{Omega }_{{rm{r}}} and Ω Λ {Omega }_{Lambda } have been used to solve the Einstein field equations for the model and the resulting behaviours of the physical and dynamical quantities, with particular emphasis on late-time cosmology, are discussed. Our analysis indicates that certain choices of the defining model parameters give results consistent with the observed behaviour of the universe, such as accelerated expansion and an early anisotropy that vanishes at late times.
{"title":"The evolution of time-dependent Λ and G in multi-fluid Bianchi type-I cosmological models","authors":"A. H. Alfedeel, Amare Abebe","doi":"10.1515/astro-2022-0027","DOIUrl":"https://doi.org/10.1515/astro-2022-0027","url":null,"abstract":"Abstract In this work, cosmological solutions based on the time-dependent cosmological ( Λ Lambda ) and Newtonian ( G G ) running “constants” in the Bianchi type-I spacetime are investigated vis-à-vis known cosmological data. The observationally known values of Ω m , Ω r {Omega }_{{rm{m}}},{Omega }_{{rm{r}}} and Ω Λ {Omega }_{Lambda } have been used to solve the Einstein field equations for the model and the resulting behaviours of the physical and dynamical quantities, with particular emphasis on late-time cosmology, are discussed. Our analysis indicates that certain choices of the defining model parameters give results consistent with the observed behaviour of the universe, such as accelerated expansion and an early anisotropy that vanishes at late times.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"198 - 204"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48322079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This article is devoted to the discovery of comets at the Vilnius Observatory together with the orbital analysis of dynamically interesting comets, namely 322P. We studied the orbital evolution of comet 322P with and without non-gravitational effects. It turned out that many of the comet’s orbital clones go into and out of retrograde orbits, sometimes repeatedly. The reason for such dramatic changes in the inclination of the orbit is the origin of comet 322P close to mean motion resonance 3:1 with Jupiter, ejecting them from there and, consequently, bringing the clones closer to the terrestrial group of planets. In this way, the clones of comet 322P enter retrograde orbits and reside there several ky to several My.
{"title":"Observational data and orbits of the comets discovered at the Vilnius Observatory in 1980–2006 and the case of the comet 322P","authors":"I. Wlodarczyk, K. Černis","doi":"10.1515/astro-2022-0023","DOIUrl":"https://doi.org/10.1515/astro-2022-0023","url":null,"abstract":"Abstract This article is devoted to the discovery of comets at the Vilnius Observatory together with the orbital analysis of dynamically interesting comets, namely 322P. We studied the orbital evolution of comet 322P with and without non-gravitational effects. It turned out that many of the comet’s orbital clones go into and out of retrograde orbits, sometimes repeatedly. The reason for such dramatic changes in the inclination of the orbit is the origin of comet 322P close to mean motion resonance 3:1 with Jupiter, ejecting them from there and, consequently, bringing the clones closer to the terrestrial group of planets. In this way, the clones of comet 322P enter retrograde orbits and reside there several ky to several My.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"244 - 255"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44606441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract With the development of human space technology, more and more astronauts fly into space. With the rapid development of commercial aerospace, more ordinary people will go to space for sightseeing. However, it should not be ignored that microgravity, space radiation, relative geometry, and orbit of space stations have various effects on the health of astronauts. In recent years, scholars in various countries have made considerable research progress in this field. This article analyzes the research history and current situation of this field, including the individual effects of space radiation, microgravity, orbit, and relative geometry, as well as their comprehensive effects. In addition, various nursing measures have been investigated.
{"title":"Research progress on the effects of microgravity and space radiation on astronauts’ health and nursing measures","authors":"Xinhua Cao","doi":"10.1515/astro-2022-0038","DOIUrl":"https://doi.org/10.1515/astro-2022-0038","url":null,"abstract":"Abstract With the development of human space technology, more and more astronauts fly into space. With the rapid development of commercial aerospace, more ordinary people will go to space for sightseeing. However, it should not be ignored that microgravity, space radiation, relative geometry, and orbit of space stations have various effects on the health of astronauts. In recent years, scholars in various countries have made considerable research progress in this field. This article analyzes the research history and current situation of this field, including the individual effects of space radiation, microgravity, orbit, and relative geometry, as well as their comprehensive effects. In addition, various nursing measures have been investigated.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"300 - 309"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47947993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract An integrated ranging and differential one-way range (DOR) signal design is implemented. The design utilizes the regenerative pseudo-noise ranging scheme and one pair of dedicated DOR tones for the deep space United X Band system. To demonstrate its effectiveness, it was applied to China’s Tianwen-1 orbiter and compared with the classic and normal designs. Using the link budget and error analysis methods, the measurement accuracy and communication ability were assessed. Results show that the novel design achieves better performance compared with that of the classic and normal designs. In the applied case, the power efficiency improved by > 30 % gt 30 % , two-way ranging precision improved from 0.50 to 0.09 m, and the two-way Doppler precision improved by 20% compared with those of the classic one. In addition, the spacecraft thermal noise during Delta-DOR measurements was slightly reduced. Owing to the higher downlink residual carrier, the supported telemetry data rate increased by 50%. Compared with the normal one, a higher downlink residual carrier (by 0.35 dB) was achieved by the novel design and resulted in slightly better ranging and Doppler accuracies. The novel design has a good technical foundation and is expected to be adopted in China’s future lunar and deep space explorations.
{"title":"Integrated design of ranging and DOR signal for China's deep space navigation","authors":"De-Zhen Xu, Lei Huang, Shaowu Chen","doi":"10.1515/astro-2022-0200","DOIUrl":"https://doi.org/10.1515/astro-2022-0200","url":null,"abstract":"Abstract An integrated ranging and differential one-way range (DOR) signal design is implemented. The design utilizes the regenerative pseudo-noise ranging scheme and one pair of dedicated DOR tones for the deep space United X Band system. To demonstrate its effectiveness, it was applied to China’s Tianwen-1 orbiter and compared with the classic and normal designs. Using the link budget and error analysis methods, the measurement accuracy and communication ability were assessed. Results show that the novel design achieves better performance compared with that of the classic and normal designs. In the applied case, the power efficiency improved by > 30 % gt 30 % , two-way ranging precision improved from 0.50 to 0.09 m, and the two-way Doppler precision improved by 20% compared with those of the classic one. In addition, the spacecraft thermal noise during Delta-DOR measurements was slightly reduced. Owing to the higher downlink residual carrier, the supported telemetry data rate increased by 50%. Compared with the normal one, a higher downlink residual carrier (by 0.35 dB) was achieved by the novel design and resulted in slightly better ranging and Doppler accuracies. The novel design has a good technical foundation and is expected to be adopted in China’s future lunar and deep space explorations.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"358 - 365"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45460810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Extraplanar structures of ionized gas are detected in numerous edge-on galaxies. Whether HII regions or supernovae (SNe) responsible for its ionization is still debated. Here, we consider the H α {rm{H}}alpha emissivity from shells of superbubbles driven by SNe explosions in a stellar cluster located either in the midplane or above the midplane of the disc. We found that these shells form filamentary structures emitting brightly in H α {rm{H}}alpha line at height of ∼ 0.6 sim 0.6 – 1.6 kpc 1.6hspace{0.33em}{rm{kpc}} above the disc depending on cluster location and gas metallicity. The H α {rm{H}}alpha surface brightness ranges within ∼ 1 0 − 17 sim 1{0}^{-17} – 1 0 − 16 erg s − 1 cm − 2 arcsec − 2 1{0}^{-16}hspace{0.33em}{rm{erg}}hspace{0.33em}{{rm{s}}}^{-1}hspace{0.33em}{{rm{cm}}}^{-2}hspace{0.33em}{{rm{arcsec}}}^{-2} are close to the values observed in edge-on galaxies. We conclude that the H α {rm{H}}alpha emission of extraplanar structures can be explained by recombination in collisionally ionized gas of unstable shells driven by multiple SNe.
{"title":"Hα emission from gaseous structures above galactic discs","authors":"E. Vasiliev, S. A. Drozdov, Y. Shchekinov","doi":"10.1515/astro-2022-0012","DOIUrl":"https://doi.org/10.1515/astro-2022-0012","url":null,"abstract":"Abstract Extraplanar structures of ionized gas are detected in numerous edge-on galaxies. Whether HII regions or supernovae (SNe) responsible for its ionization is still debated. Here, we consider the H α {rm{H}}alpha emissivity from shells of superbubbles driven by SNe explosions in a stellar cluster located either in the midplane or above the midplane of the disc. We found that these shells form filamentary structures emitting brightly in H α {rm{H}}alpha line at height of ∼ 0.6 sim 0.6 – 1.6 kpc 1.6hspace{0.33em}{rm{kpc}} above the disc depending on cluster location and gas metallicity. The H α {rm{H}}alpha surface brightness ranges within ∼ 1 0 − 17 sim 1{0}^{-17} – 1 0 − 16 erg s − 1 cm − 2 arcsec − 2 1{0}^{-16}hspace{0.33em}{rm{erg}}hspace{0.33em}{{rm{s}}}^{-1}hspace{0.33em}{{rm{cm}}}^{-2}hspace{0.33em}{{rm{arcsec}}}^{-2} are close to the values observed in edge-on galaxies. We conclude that the H α {rm{H}}alpha emission of extraplanar structures can be explained by recombination in collisionally ionized gas of unstable shells driven by multiple SNe.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"99 - 105"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45433581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.51194/vak2021.2022.1.1.054
B. Losovsky
Abstract A characteristic property of pulsars is pulsed periodic radio emission, which has a high stability of periods. Despite the high stability of the emission periods of pulsars, monitoring the time of arrival of pulses (timing) shows the presence of different types of irregularities: variations of residual deviations, changes in the shape of the pulse, switching on and off of radio emission, and rotation discontinuities. Numerous observations of the radio emission of pulsars indicate that they are caused mainly by processes occurring in the pulsar’s magnetosphere. The special interest causes the observations of a pulsar in the Crab Nebula, performed, in particular, at Jodrell Bank and Pushchino Radio Astronomy Observatory of Lebedev Physical Institute. The connection between the scattering of radio pulses and the measure of the pulsar dispersion, which was established earlier in Pushchino together with Jodrell Bank, has been confirmed. The observed variations in the scattering of radio pulses and their partial correlation with the dispersion measure are explained by the eclipse of the pulsar by plasma clouds with electron density fluctuations significantly exceeding the corresponding fluctuations in the interstellar medium. The question of a possible connection between glitches, dispersion measure variations, radio pulses scattering, and gamma-ray flares is discussed.
{"title":"The specifics of pulsar radio emission","authors":"B. Losovsky","doi":"10.51194/vak2021.2022.1.1.054","DOIUrl":"https://doi.org/10.51194/vak2021.2022.1.1.054","url":null,"abstract":"Abstract A characteristic property of pulsars is pulsed periodic radio emission, which has a high stability of periods. Despite the high stability of the emission periods of pulsars, monitoring the time of arrival of pulses (timing) shows the presence of different types of irregularities: variations of residual deviations, changes in the shape of the pulse, switching on and off of radio emission, and rotation discontinuities. Numerous observations of the radio emission of pulsars indicate that they are caused mainly by processes occurring in the pulsar’s magnetosphere. The special interest causes the observations of a pulsar in the Crab Nebula, performed, in particular, at Jodrell Bank and Pushchino Radio Astronomy Observatory of Lebedev Physical Institute. The connection between the scattering of radio pulses and the measure of the pulsar dispersion, which was established earlier in Pushchino together with Jodrell Bank, has been confirmed. The observed variations in the scattering of radio pulses and their partial correlation with the dispersion measure are explained by the eclipse of the pulsar by plasma clouds with electron density fluctuations significantly exceeding the corresponding fluctuations in the interstellar medium. The question of a possible connection between glitches, dispersion measure variations, radio pulses scattering, and gamma-ray flares is discussed.","PeriodicalId":19514,"journal":{"name":"Open Astronomy","volume":"31 1","pages":"189 - 197"},"PeriodicalIF":0.7,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42945439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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