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X-ray emission properties from Circinus X-1 Circinus X-1的x射线发射特性
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790601156709
V. V. Fidelis
{"title":"X-ray emission properties from Circinus X-1","authors":"V. V. Fidelis","doi":"10.1080/10556790601156709","DOIUrl":"https://doi.org/10.1080/10556790601156709","url":null,"abstract":"The X-ray activity of Circinus X-1, a periodically flaring source, was studied using observational data from the all-sky monitor onboard the Rossi X-ray Timing Explorer orbital observatory in the 2–12 keV energy band. The cross-correlation analysis of the 1 day averaged data set obtained in 2001 has confirmed the fundamental 16.6 day orbital period. The variability pattern of source emission in September–November 2005 has a complicated structure that may be explained by X-ray emission pressure on the accretion disc and periodically ejected matter. The spectral analysis of X-ray emission has revealed the source behaviour in high- and low-activity states that may be caused by differential absorption of emission by the dynamically changed environment in a close binary system.","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"88 1","pages":"235-239"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86485902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Escaping and trapped orbits in a “bare” Seyfert 1 nucleus dynamical model 在“裸”塞弗特1核动力学模型中逃逸和捕获轨道
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790701524442
N. Papadopoulos, N. Caranicolas
{"title":"Escaping and trapped orbits in a “bare” Seyfert 1 nucleus dynamical model","authors":"N. Papadopoulos, N. Caranicolas","doi":"10.1080/10556790701524442","DOIUrl":"https://doi.org/10.1080/10556790701524442","url":null,"abstract":"The nature and behaviour of the orbits in a “bare” Seyfert 1 dynamical model is studied. This model is subject to external perturbation caused by nearby galaxies. Numerical calculations suggest that, when the external perturbation is high the nature of the majority of orbits change from regular to chaotic. For higher external perturbations the zero velocity curves open and a number of orbits goes to infinity. In addition to those orbits, there are orbits that do not escape at all. Theoretical evidence shows that these orbits have an additional quasi-integral of motion which is a generalization of the angular momentum of the test particle.","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"2004 1","pages":"301-309"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83031188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
The broad emission lines in the active galactic nucleus Fairall 9 在活动星系核Fairall 9的宽发射线
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790701685615
L. S. Nazarova, N. Bochkarev, P. O'Brien
{"title":"The broad emission lines in the active galactic nucleus Fairall 9","authors":"L. S. Nazarova, N. Bochkarev, P. O'Brien","doi":"10.1080/10556790701685615","DOIUrl":"https://doi.org/10.1080/10556790701685615","url":null,"abstract":"This paper reports on a study of UV and optical spectra of the active galaxy Fairall 9 taken as a part of the International AGN Watch database. CIV/Lyα, Lyα/Hs and Hα/Hs ratios have been measured at different radial velocities, which are varied across the line profiles. The ratio Lyα/Hs is low in the low-velocity centre of the lines, but increases a little in the high-velocity wings. The CIV/Lα and Hα/Hs line intensities ratios, however, are high at the line centre but become low in the wings. Modelling with the photoionization code CLOUDY shows that the observed line ratios can be described by two systems of clouds. One corresponds to the high-ionization line zone (HIL) with an electron density, ne∼ 108−10 cm−3. It is presumably located above the accretion disk or in the jets. The other system corresponds to the low-ionization line zone (LIL), which is probably a part of the accretion disk and which has a higher electron density, ne∼ 1012−13 cm−3. The possible geometry of the BLR in Fairall 9 is discussed.","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"22 1","pages":"401-408"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85624075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
0836+710. High quality ground and VSOP images 0836 + 710。高质量的地面和VSOP图像
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790701592167
A. Chuprikov
{"title":"0836+710. High quality ground and VSOP images","authors":"A. Chuprikov","doi":"10.1080/10556790701592167","DOIUrl":"https://doi.org/10.1080/10556790701592167","url":null,"abstract":"Some results from the processing of data of two Very Long Baseline Interferometry (VLBI) observations of well-known quasar 0836+710 are presented. This source demonstrates a big parsec-scale jet with reach structure in S (2300 MHz), C (4980 MHz), and X (8400 MHz) frequency bands and has been included into the Japanese mission titled VSOP (VLBI Space Orbital Program) as well as into the future Russian mission titled ‘RADIOASTRON’ source listing. The radio images presented here illustrate some interesting properties of radio structure of 0836+710. The processing of data has been carried out with the software ‘Astro Space Locator’ (ASL for Windows).","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"113 1","pages":"371-378"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73704135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Anomalies of an external and internal gravitational field of upper Earth layers in square law approximation 地球上层内外引力场的平方定律近似异常
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790701592134
L. P. Nasonova, N. A. Chujkova
{"title":"Anomalies of an external and internal gravitational field of upper Earth layers in square law approximation","authors":"L. P. Nasonova, N. A. Chujkova","doi":"10.1080/10556790701592134","DOIUrl":"https://doi.org/10.1080/10556790701592134","url":null,"abstract":"The explicit form for the quadratic contribution to the gravitational field from the dipole distributed anomalous masses is found. The anomalous masses are represented in the form of layers of variable height, arranged relative to the reference ellipsoid. The solution is reduced to the mathematical problem of finding an expression for the coefficients of expansion in terms of spherical harmonics of the square of any function that can be presented as a finite series of spherical harmonics, in terms of the coefficients of this initial series. The formulas have been calculated using mathematical modelling of symbol computation using computer algebra packages. The results obtained are illustrated using the example of the contribution from relief masses and density jumps on the Mohorovicic (Moho) discontinuity.","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"26 1","pages":"361-369"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81223714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Charging of dust particles in molecular clouds 分子云中尘埃粒子的带电
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790601156667
Y. Shchekinov
{"title":"Charging of dust particles in molecular clouds","authors":"Y. Shchekinov","doi":"10.1080/10556790601156667","DOIUrl":"https://doi.org/10.1080/10556790601156667","url":null,"abstract":"Abstract In molecular clouds the dust charge can be determined by non-thermal electrons from cosmic-ray ionization. If the energy of the non-thermal electrons is E≥2 keV and their fraction is only 10−3–10−4 of the thermal electrons in a molecular gas, the grain charge can be as high as | z | ≈ 10 in the range of gas densities n≈ 105–106 cm−3. In the high-density range n>106 cm−3, the grain charge approaches the thermal limit | z | ≈ 0.3.","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"110 1","pages":"227-234"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87698025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
On the date when Christianity became the state religion of Georgia 这一天，基督教成为格鲁吉亚的国教
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790601135398
M. Gigolashvili, R. Kiladze, V. Kukhianidze, G. Ramishvili
{"title":"On the date when Christianity became the state religion of Georgia","authors":"M. Gigolashvili, R. Kiladze, V. Kukhianidze, G. Ramishvili","doi":"10.1080/10556790601135398","DOIUrl":"https://doi.org/10.1080/10556790601135398","url":null,"abstract":"In the Georgian chronicles it is specified that the acceptance of Christianity in Georgia is connected with the fact that, during a hunt, King Mirian suddenly became aware that it was dark and that the Sun had disappeared from the sky. Accordingly, it is considered that Christianity in Georgia was announced to be the state religion after this event in the fourth century. In the 1930s the well-known Georgian historian Ivane Javakhishvili asked astronomers to answer the question of whether there was a solar eclipse in Georgia in the fourth century or not. Now we have found that a total solar eclipse occurred in Georgia on 6 May 319 AD.","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"5 1","pages":"199-201"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77162372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
An investigation of the tidally driven period changes in detached binary systems through O-C time series analysis: the case of RT And and WY Cnc † 用O-C时间序列分析分离双星系统潮汐驱动周期变化的研究:以RT和WY Cnc为例
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790701300587
N. Nanouris, A. Kalimeris, E. Antonopoulou
{"title":"An investigation of the tidally driven period changes in detached binary systems through O-C time series analysis: the case of RT And and WY Cnc †","authors":"N. Nanouris, A. Kalimeris, E. Antonopoulou","doi":"10.1080/10556790701300587","DOIUrl":"https://doi.org/10.1080/10556790701300587","url":null,"abstract":"Detached binary systems are subjected to a variety of physical mechanisms which are able to change their period in a continuous way and in a broad band of timescales. Assuming that these changes should be detectable in O–C diagrams in a way specified by the physical theory of the underlying mechanisms, we carry out a preliminary study in a properly selected sample of detached binaries, where no mass transfer is expected. We are primarily interested in finding traces of tidal moments in observed orbital period changes (possibly coupled with stellar wind angular momentum losses). We focus our attempts on two short-period chromospherically active binaries (RT And and WY Cnc), whose expected period changes rates are found to be close to those derived by means of time series analysis. Emphasis is also given to systems which show a remarkably constant orbital period, in disagreement with the values expected by theory. †This paper was originally due to be published in the Special Issue: Close Binary Stars in Mod...","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"75 1","pages":"245-250"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86179241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The low-frequency radio recombination lines formed in the extremely extended C II regions 低频无线电复合线形成于极延伸的C II区
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790601135406
N. I. Rovens'kaya
{"title":"The low-frequency radio recombination lines formed in the extremely extended C II regions","authors":"N. I. Rovens'kaya","doi":"10.1080/10556790601135406","DOIUrl":"https://doi.org/10.1080/10556790601135406","url":null,"abstract":"Abstract Currently, nearly ten radio recombination lines are observed in the extremely extended C II regions towards Cassiopeia A, G00-00, G05-00 and G10-00. The centimetre linewidths are formed owing to the Doppler effect. The decametre linewidths are the result of combinations of the Doppler broadening, radiation interaction and electron collision transition rate. The electron collision width is determined in the impact approximation, which can be employed for highly excited atom states with the principal quantum and line numbers n in the case when 1.6×105 K/n 2 T e≪1, n>500. The decametre linewidth components are tabulated together with the calculated electron densities. The dimensions of the C II regions are directly determined by using the steep dependence of the optical depth of a centimetre recombination line on the electron temperature. Solving the optical depth problem and having accounted for the spontaneous and collision transition rates in the balance equations, the highly excited atom non-equ...","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"238 1","pages":"203-209"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77013578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Influence of additional dimensions on the dynamics of the expansion of the Universe 附加维度对宇宙膨胀动力学的影响
Astronomical and Astrophysical Transactions Pub Date : 2007-10-01 DOI: 10.1080/10556790701594973
A. Pakhomov
{"title":"Influence of additional dimensions on the dynamics of the expansion of the Universe","authors":"A. Pakhomov","doi":"10.1080/10556790701594973","DOIUrl":"https://doi.org/10.1080/10556790701594973","url":null,"abstract":"Abstract We consider the possibility of the influences of additional dimensions on the dynamics of the expansion of our Universe. It is shown that this influence is expressed only through the anisotropy parameter of additional dimensions. In the isotropic (in relation to additional dimensions) case the dynamics of our world remains constant. All calculations were carried out for a single-component ideal fluid with power diagonal metrics. The dynamic characteristics of the scale factor have allowed us to draw a conclusion about the physical nature of the initial substance.","PeriodicalId":52135,"journal":{"name":"Astronomical and Astrophysical Transactions","volume":"84 1","pages":"379-389"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83867598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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