强质子耀斑活动区的形态和旋转特征

本研究结果表明，同一黑子群在日面期间的顺或反时针方向的旋转运动会先后并存。质子耀斑前１～２天，黑子群的旋转角速度达到极大，耀斑后，磁绳的松弛，黑子群可能会反向转转，强的剪切过程和质子耀斑可能会再度出现，强质子耀斑活动区的共同特征是：（１）形态为单个团状结构δ型黑子，即众多异极性本影核紧锁在同一黑子半影中，（２）黑子面积〉１０００×１０＾－６半球面积，日面跨度〉１０°；（３）黑子群有快速的旋转活动     

22周强质子耀斑活动区的特征

本文研究了22周中的9个强质子耀斑活动区的共同特征,研究结果表明:单个团状结构黑子,即众多异极性黑子本影核紧锁在同一半影结构中的δ型黑子是强质子耀斑活动区的典型形态特征。黑子群的旋转是质子耀斑活动区的又一重要特征,黑子群的旋转方向与日面南、北半球无关。强质子耀斑的爆发总是在黑子群旋转角度达到正或负相极大之后出现。质子耀斑后,磁绳的松弛,黑子群可能会出现反向旋转,强的剪切过程和质子耀斑可能会再度出现。     

质子活动与太阳黑子群

本文对太阳活动第２１周、２２周（１９７６年—１９９２年间）９７个质子活动区进行统计分析，包括活动区的面积、型别、磁结构、半影纤维等，结果表明：７５％的质子耀斑产生于面积为５００≤Ｓｐ≤３０００单位的黑子群中；耀斑爆发前一天及后一天活动区面积有显著减少；质子活动区含δ复杂磁结构的占７０％；具有半影旋涡形态的质子活动区中，约７７％的耀斑发生在旋涡黑子出现以后。     

质子活动与太阳黑子群

本文对太阳活动第２１周、２２周（１９７６年－１９９２年间）９７个质子活动区进行统计分析，包括活动区的面积、型别、磁结构、半影纤维等，结果表明：７５％的质子耀斑产生于面积为５００≤Ｓｐ≤３０００单位的黑子群中；耀斑爆发前一天及后一天活动区面积有显著减少，质子活动区含δ复杂磁结构的占７０％；具有半影旋涡形态的质子活动区中，约７７％的耀斑发生在旋涡黑子出现以后。     

AR5395活动区的光学和射电辐射特征

黑子群快速的旋转(先反时针转,后顺时针转,质子耀斑前1—2天内旋转角度最大)、活动区强的SVC辐射、以及SVC和爆发峰值流量频谱的极大始终在8800MHz附近等与质子耀斑密切相关。同极性磁形中浮现或消失具有反极性的新磁流区域、磁场     

AR5060——具有复杂结构的大黑子但没有大耀斑发生的太阳活动区(英文)

AR5060是No.Ⅳ联测期中的第二个目标活动区。它从1988年6月25日东边缘初现到7月8日转出西边缘消失的14天中,黑子群一直保持最复杂的FKC、EKC型和最复杂的BGD磁型。6月29日黑子群面积发展到3000面积单位,是第22周以来第一群最大的黑子(更大的是1989年3月的AR5395,面积达3600单位)。该活动区的黑子群发生过强烈的运动和磁性重联。似乎具备发生强烈大耀斑的位形特征和动力学条件,可是在这期间,全球耀斑监测所观测到的120多个耀斑(据SGD)中,亚耀斑占81％,1级耀斑占15％,2级耀斑只有3个占4％,而且这3个2级耀斑的X射线级别只达到M6.5,M9.2,M3.9,没有一个达到X级。 在AR5060活动区耀斑活动高峰期的6月28日,29日,30日和7月1日这四天中,云南天文台26CM太阳望远镜观测到其中一个2B/M6.5耀斑(1988年6月29日0737UT)、几个1级耀斑和其它许多亚耀斑。从黑子群和色球单色照片上作耀斑发生点同黑子相对位置的比较,结果是出乎意料的,在结构复杂、运动剧烈的黑子群内部发生的都是小耀斑,而3个2B/M级耀斑都发生在黑子群以外只有卫星黑子浮现和消失的时期和地点。     

YR80—575号活动区的大黑子群

在国际太阳活动峰年期间,云南天文台观测到80—575号活动区,日面坐标S12L97,过中经日期11月11.7日,从11月5日到17日连续观测13天。 该活动区在日面通过期间,频繁地爆发耀斑,其中有一部分耀斑有强烈的x-线和短波突然中断事件相伴生。11月6日0542UT.,发生的一个X9/3B级耀斑伴生的X级x-线事件,强烈程度仅次于1978年7月11日的那次。 该活动区的形态特征之一是它的黑子群为第21太阳活动周以来面积最大的一群。它是云台80—529老活动的回归黑子群,许多新黑子在老黑子的周围浮现,从而变成一个非常复杂的FKC型黑子群,面积大,磁场梯度大,具有δ-结构。全群的平均磁场强度约为2000高斯,在几个主黑子中测量到最大磁场为3300高斯。 这个复杂的黑子群中,观测到了强烈的运动、旋转,分离,合并和黑子间的相互作用。老黑子中发现一个反常光桥,它是在两个本影合并起来时形成,而不象通常在黑子将分裂时出现。     

AR5060黑子的形态分析(英文)

紫台观测编号为1988年第115号黑子群(Boulder编号为5060)是1988年6月26日由日面东边缘转出来,于7月9日转到日面西边缘背后,在7月18日过日面中心经圈,历时共13天。这个黑子群的日面坐标是S20和L5。 该黑子群比较大而复杂。在它通过日面期间,最大时的较正面积达2834(以半球面积的百万分之一为单位),这是从第20周至88年以来所观测到的面积最大的黑子群。此黑子群的型别(按麦氏分类)属最复杂的类型,基本上一直保持为FKC型。在6月26日从日面东边缘转出来时,黑子群呈现为一种异常排列,即其前导黑子位于高纬度,后随黑子处于低纬度,而且呈现明显的旋转运动,其转动方向是反时针的。它在过日面期间还不断的有自身的分裂和移动等特性。另外,该黑子群的磁性结构也异常复杂,在经过日面期间始终为δ结构。基于以上这些形态特征,促使这黑子群在通过日面这段时间内,先后产生了一系列的耀斑活动(其中有44个C级和13个M级的X射线耀斑),并大都伴随着显著的射电爆发,而且引起了多次相应的电离层突然骚动(SID)(有60个耀斑伴随着相应的电离层突然骚扰)。     

第22周中最强烈的太阳活动区

本文根据观测资料，选取五个指标：活动区中黑子群面积，Ｘ级Ｘ射线耀斑指数，１０．７ｃｍ射电爆发峰值流量，太阳总辐射流量短期大跌落以及质子事件流量，从第２２周的３９６６个活动区中综合评估筛选出ＡＲ５３９５，ＡＲ６５５５和ＡＲ６６５９等１３个最强烈的活动区，供太阳物理和日地物理研究人员进一步研究。本文还简要分析了这１３个活动区的时空分布的不均匀性和相对集中性等特点。     

AR5395的黑子群特征

5395黑子群是1989年3月6日由日面东边缘转出来,于3月19日转到日面西边缘。3月12.8日过日面中心经圈。它的日面坐标是N34,L257。 该黑子群是第20太阳活动周以来面积最大的黑子群,且出现在30°以上的高纬度区域,更为罕见。它在通过日面期间,频繁地产生耀斑活动(共194个Hα耀斑),其     

Equation of state and anisotropy of pressure of magnetars

Magnetars are the neutron stars with the highest magnetic fields up to 10¹⁵–10¹⁶ G. It has been proposed that they are also responsible for a variety of extra-galactic phenomena, ranging from giant flares in nearby galaxies to fast radio bursts. Utilizing a relativistic mean field model and a variable magnetic field configuration, we investigate the effects of strong magnetic fields on the equation of state and anisotropy of pressure of magnetars. It is found that the mass and radius of low-mass magnetars are weakly enhanced under the action of the strong magnetic field, and the anisotropy of pressure can be ignored. Unlike other previous investigations, the magnetic field is unable to violate the mass limit of the neutron stars.     

A survey of orbits of co-orbitals of Mars

Many asteroids with a semimajor axis close to that of Mars have been discovered in the last several years. Potentially some of these could be in 1:1 resonance with Mars, much as are the classic Trojan asteroids with Jupiter, and its lesser-known horseshoe companions with Earth. In the 1990s, two Trojan companions of Mars, 5261 Eureka and 1998 VF₃₁, were discovered, librating about the L₅ Lagrange point, 60° behind Mars in its orbit. Although several other potential Mars Trojans have been identified, our orbital calculations show only one other known asteroid, 1999 UJ₇, to be a Trojan, associated with the L₄ Lagrange point, 60° ahead of Mars in its orbit. We further find that asteroid 36017 (1999 ND₄₃) is a horseshoe librator, alternating with periods of Trojan motion. This asteroid makes repeated close approaches to Earth and has a chaotic orbit whose behavior can be confidently predicted for less than 3000 years. We identify two objects, 2001 HW₁₅ and 2000 TG₂, within the resonant region capable of undergoing what we designate “circulation transition”, in which objects can pass between circulation outside the orbit of Mars and circulation inside it, or vice versa. The eccentricity of the orbit of Mars appears to play an important role in circulation transition and in horseshoe motion. Based on the orbits and on spectroscopic data, the Trojan asteroids of Mars may be primordial bodies, while some co-orbital bodies may be in a temporary state of motion.     

Estimation of the Time Scale of Merging of the Components of Contact Binaries of the W UMa Type

Time scales of the transition from contact binary systems of the W UMa type to single stars of the blue straggler type are estimated. A model of one-way mass transfer from the primary component to the companion inside a common envelope (Eggen et al.) and a model of a contact binary lying on the zero-age main sequence with a companion that is losing mass (F. van't Veer) are used to calculate these scales. The merging times of components were calculated for 304 contact systems of the W UMa type from the Catalog of Approximate Photometric and Absolute Elements of Eclipsing Variable Stars on a scale of loss of mass and orbital angular momentum due to magnetic braking, under the assumption of synchronization of the axial rotation and orbital revolution. On the basis of the resulting statistics, the characteristic merging scales are 0.4-0.6 and 0.5-0.7 Gyr, respectively, for the above two models. The results of a comparison with the work of other authors are discussed.     

Modeling of lightcurves of binary asteroids

We present a numerical method for inverting long-period components of lightcurves of asynchronous binary asteroids. Data of five near-Earth binary asteroids, (175706) 1996 FG₃, (65803) Didymos, (66391) 1999 KW₄, (185851) 2000 DP₁₀₇ and (66063) 1998 RO₁, for two of them from more than one apparition, were inverted. Their mutual orbits' poles and Keplerian elements, size ratios, and ellipsoidal shape axial ratios were estimated via this inversion. The pole solutions and size ratios for 1999 KW₄ and 2000 DP₁₀₇ are in a good agreement with independent estimates from radar measurements. We show that uncertainties of estimates of bulk densities of binary systems can be large, especially when observed on short arcs.     

Influence of Neutron Star Parameters on Evolutions of Different Types of Pulsar

Influences of the mass, moment of inertia, rotation, absence of stability in the atmosphere and some other parameters of neutron stars on the evolution of pulsars are examined. It is shown that the locations and evolutions of soft gamma repeaters, anomalous X-ray pulsars and other types of pulsar on the period versus period derivative diagram can be explained adopting values of B < 10¹⁴ G for these objects if they have smaller mass (e.g. about 0.5 Solar mass) compared to the conventionally adopted values of mass. This approach gives the possibility to explain many properties of different types of pulsar.     

Investigation of Times of Minima of Selected Early-Type Eclipsing Binaries

New precise times of minimum light for several early-type eclipsing binaries were obtained at three observatories. The changes of period of the following measured binaries are discussed: V1182 Aql, LY Aur, SZ Cam, FZ CMa, QZ Car, LZ Cen, V606 Cen, AH Cep and TU~Mus.     

Flattening of galaxies of different morphological types in subclusters of Coma

This paper deals with the observed variation in the flattening of galaxies with the density of galaxies in the subclusters of Coma surrounding NGC 4889, NGC 4874, and NGC 4839 based on data from the Abastumani Combined Catalog of Galaxies. The mean values of the observed ratios of the diameters of the galaxies, as well as histograms of their distributions, indicate that in the central, dense regions of the subclusters within a volume of 0.5h ₇₅ ⁻¹ Mpc³, E and S0 type galaxies are close to spheroidal. A significant reduction in the mean values of the diameters of the galaxies in the subclusters is noted, regardless of their morphology relative to the galaxies in the halo of the Coma cluster. In the subclusters, spiral galaxies are found with a hydrogen deficit that is more than 5 times the hydrogen deficit in spirals within the halo of the cluster. According to their 3-D coordinates, most of the galaxies with a hydrogen deficit are located closer to the south-east edge of the subcluster surrounding NGC 4874 near an extended gas filament in the x-ray region. This may indicate that the subcluster is moving toward a central condensation of faint galaxies in the Coma cluster and a possible merger with it. __________ Translated from Astrofizika, Vol. 50, No. 3, pp. 355–368 (August 2007).     

淮河洪水的可公度性分析

分析了上两个世纪发生在淮河的洪水事件的可公度性，根据其可公度值及其黄金分割点指出1991年与2003年淮河洪水的不可避免，最后讨论了可公度性的局限及淮河洪水可公度值的可能机制。     

基于STK的寿命末期GEO卫星轨道演化分析

地球同步轨道上的GEO卫星接近寿命末期时,星上的有效载荷和电子元器件等仍能正常应用,此时如果只做东西方向的位置保持,可以大幅度延长卫星的在轨工作寿命。简要介绍了引起GEO卫星轨道变化的主要摄动力,利用STK软件分析寿命末期GEO卫星的运动规律,并给出这类GEO卫星轨道演化的仿真分析流程,用以指导寿命末期GEO卫星的开发应用工作。     

On the application of optimization methods to the determination of members of families of periodic solutions

The techniques used for the numerical computation of families of periodic orbits of dynamical systems rely on predictor-corrector algorithms. These algorithms usually depend on the solution of systems of approximate equations constructed from the periodicity conditions of these orbits. In this contribution we transform the root finding procedure to an optimization one which is applied on an objective function based on the exact periodicity conditions. Thus, the determination of periodic solutions and families of such orbits can be accomplished through unconstrained optimization. In this paper we apply and compare some well-known minimization methods for the solution of this problem. The obtained results are promising. This revised version was published online in July 2006 with corrections to the Cover Date.