Peculiar objects in the birthplaces of radio pulsars -- stellar-mass black hole candidates

We perform a search for stellar-mass black hole candidates in the spatial regions with increased probability of their occurrence, isolated based on the evolutionary scenarios for compact objects originating in disrupted binaries. We analyze the sources located in these regions with available spectral or photometric data, as well as measured proper motions and distances. Nine objects that exhibit characteristics corresponding to theoretical predictions for isolated black holes are marked for further study as black hole candidates

Турецкая республика как объект изучения научно-политического сообщества США: концептуализация проблемы и обзор методологии исследований

The article presents the main approaches developed within US scientific and political community concerning the Republic of Turkey and the Middle East region as a whole. These theoretical developments are a long-term conceptual framework of US foreign policy in the Middle East; moreover, the fact of American participation in the processes of political and military transformation of the region, as well as the desire to model the dynamics of these processes, is recognized in modern American historiography. In this context, research of the situation in the region, should be analyzed not through the prism of the theoretical understanding, but be perceived as political technologies designed to ensure the implementation of US foreign policy goals. Therefore the study of American historiography, analysis of new research approaches and methods are of scientific interest, but it must be noted that most research of well-known representatives of American scientific and political community are free from theorizing and methodological analysis, which creates certain difficulties in the study of its methodological framework.В статье представлены основные подходы, разрабатываемые научно-политическим сообществом США касательно Турецкой Республики и ближневосточного региона в целом. Теоретические разработки американских специалистов представляют собой концептуальную основу долгосрочной внешней политики США на Ближнем Востоке; более того, подтверждают факт американского участия в процессах политической и военной трансформации региона, а также стремление моделировать динамику развития этих процессов. В этой связи исследования, посвященные анализу ситуации в регионе, целесообразно рассматривать не столько через призму теоретического осмысления, сколько воспринимать в качестве политических технологий, призванных обеспечить реализацию внешнеполитических целей США. В этом контексте изучение американской историографии, анализ новых исследовательских подходов и методов исследований представляет несомненный научный интерес, однако приходится констатировать, что большинство работ известных представителей американского научно-политического сообщества отличаются публицистичностью и не содержат серьезного теоретического и методологического анализа, что создает сложности в процессе исследования их методологической базы

ОСМАНСКОЕ НАСЛЕДИЕ ТУРЦИИ В СОВРЕМЕННОЙ АМЕРИКАНСКОЙ ИСТОРИОГРАФИИ

The article presents the main approaches developed within US scientific and political community concerning the most challenging issues of the Ottoman history reflected in the policies of modern Turkey, and still having impact on the role and place of Turkish Republic in the system of international relations in general.В статье освещены основные подходы, представленные научно-политическим сообществом США касательно наиболее актуальных проблем османской истории, отраженных в политике современной Турции и продолжающих оказывать влияние на роль и место Республики в системе современных международных отношений в целом

EAEU — Cuba: Institutionalization of Interaction and the Potential of Modern Cooperation

The research is aimed at studying the process of establishment and development of Eurasian-Cuban partnership under new geopolitical conditions and its role in the emerging global economy and geopolitics. The author reviews the methodical work of Eurasian Economic Commission as well as the system-forming role of Russia in building a mutually beneficial partnership with the Republic of Cuba, the priorities of interaction and the factors of influence are defined.Aim. To appraise significance and potential of the Cuban direction in the Eurasian Economic Union strategy in the context of the emerging multipolarity.Tasks. To study the process of institutionalization of the Eurasian-Cuban partnership, main areas of cooperation, current trends and factors of influence, determining the prospects for interaction.Methods. A combination of general scientific theoretical and special methods is used. The method of comparative analysis and the logical method are of prime importance. When working with regulatory and legislative sources, the normative method is used.Results. The potential of EAEU — Cuba relations has not been implemented yet; there are clear disproportions between the member countries; and the growing role of Chinese factor in the context of Eurasian-Cuban relations requires due consideration.Conclusion. Effective coordination within EAEU — Cuba — China can provide joint implementation of global challenges targeted at states’ sustainable development under the formation of a multipolar world order

Украинский кризис в исследованиях "фабрик мысли" США

The paper is a brief analysis of the main approaches developed within American “think-tanks” concerning the events taking place in Ukraine. According to most researchers, the Ukrainian crisis requires US strong engagement to confirm the key geopolitical role of the White House as the sole guarantor of the stability of the current Euro-Atlantic and the Middle Eastern security environment.В статье проводится анализ основных подходов, разрабатываемых американскими экспертами на «фабриках мысли» США в контексте событий, происходящих на Украине. По мнению большинства исследователей, украинский кризис требует активного вмешательства США для подтверждения ключевой геополитической роли Белого Дома в обеспечении стабильности сложившейся системы евроатлантической и ближневосточной безопасности

Роль Турции в восточном Средиземноморье в оценке американских исследователей

The article analyzes the main approaches developed by American analysts in research centers - the “think tanks” and universities of the United States, concerning the role of Turkey in the eastern Mediterranean in the context of the events taking place in the region at the moment. Despite the fact that there is no consensus on the future role of Turkey as an ally of the United States and NATO in the region among American experts, the need for the direct involvement of the White House in the resolution of regional conflicts is not in doubt and is determined by strategic interests of the USA in the Eastern Mediterranean and the Middle East.В статье проводится анализ основных подходов, разрабатываемых американскими аналитиками в рамках исследовательских центров - «фабрик мысли» и университетов США и касающихся роли Турции в Восточном Средиземноморье в контексте событий, происходящих в регионе в настоящее время. Несмотря на то что среди американских экспертов нет консенсуса о дальнейшей роли Турции в качестве союзника США и НАТО в регионе, необходимость непосредственного вовлечения Белого дома в разрешение региональных конфликтов не вызывает сомнений и определяется геостратегическими интересами США в Восточном Средиземноморье и на Ближнем Востоке

Searching for isolated stellar-mass black hole candidates by analyzing the kinematics of their former companions in disrupted binary systems

We performed a search for isolated stellar-mass black hole candidates based on the fact that more than 50% of radio pulsars have originated in binary systems, now disrupted, where the other component could have evolved into a black hole prior to the second supernova event in the system which caused its disruption. To this end, several relatively young isolated pulsars with known parallaxes fitting the selection criteria were traced back to their presumed birth locations. These areas were then analyzed for possible black hole candidates based on the astrometric, photometric, and spectral data available. We present the results for the first 4 pulsars in our sample, J0139+5814, J0922+0638, J0358+5413, and J1395+1616. Several possible candidates were selected for further analysis

Evidence of longterm cyclic evolution of radio pulsar periods

The measurements of pulsar frequency second derivatives have shown that they are 1e2...1e6 times larger than expected for standard pulsar spin-down law. Moreover, the second derivatives as well as braking indices are even negative for about half the pulsars. We explain these paradoxical results on the basis of the statistical analysis of the rotational parameters f0, f1 and f2 of the subset of 295 pulsars taken mostly from the ATNF database. We have found a strong correlation between f2 and f1 for both f2 > 0 (correlation coefficient r ~ 0.9) and f2 < 0 (r ~ 0.85), as well as between f0 and f1 (r ~ 0.6...0.7). We interpret these dependencies as evolutionary ones due to f1 being nearly proportional to the pulsars' age. The derived statistical relations as well as "anomalous" values of f2 are well described by assuming the existence of long-time variations of the spin-down rate. The pulsar frequency evolution, therefore, consists of secular change of f0_{ev}(t), f1_{ev}(t) and f2_{ev}(t) according to the power law with n ~ 5, the irregularities, observed within the timespan as timing noise, and the non-monotonous variations on the timescale of several tens of years, which is larger than that of the timespan. It is possible that the nature of long-term variations is similar to that of short-term ones. The idea of non-constant secular pulsars' braking index n is also analysed.Comment: 8 pages, 8 figures. To appear in Advances in Space Research in the proceedings of the 36th COSPAR Scientific Assembly, Beijing, July 200

Neutron stars from young nearby associations the origin of RXJ1605.3+3249

Many neutron stars (NSs) and runaway stars apparently come from the same regions on the sky. This suggests that they share the same birth places, namely associations and clusters of young massive stars. To identify NS birth places, we attempt to and NS-runaway pairs that could be former companions that were disrupted in a supernova (SN). The remains of recent (<few Myr) nearby (< 150 pc) SNe should still be identifiable by observing the emission of rare radioisotopes such as 26Al and 60Fe that can also be used as additional indicators to confirm a possible SN event. We investigated the origin of the isolated NS RXJ1605.3+3249 and found that it was probably born ~100 pc far from Earth 0.45 Myr ago in the extended Corona-Australis or Octans associations, or in Sco OB4 ~1 kpc 3.5 Myr ago. A SN in Octans is supported by the identification of one to two possible former companions the runaway stars HIP 68228 and HIP 89394, as well as the appearance of a feature in the gamma ray emission from 26Al decay at the predicted SN place. Both, the progenitor masses estimated by comparison with theoretical 26Al yields as well as derived from the life time of the progenitor star, are found to be ~11MSun.Comment: accepted for publication in PASA, special volume Astronomy with Radioactivities; 10 pages, 4 figures, 5 table

Search for Pairs of Isolated Radio Pulsars - Components in Disrupted Binary Systems

We have developed a method for analyzing the kinematic association of isolated relativistic objects - possible remnants of disrupted close binary systems. We investigate pairs of fairly young radio pulsars with known proper motions and estimated distances (dispersion measures) that are spaced no more than 2-3 kpc apart. Using a specified radial velocity distribution for these objects, we have constructed 100-300 thousand trajectories of their possible motion in the Galactic gravitational field on a time scale of several million years. The probabilities of their close encounters at epochs consistent with the age of the younger pulsar in the pair are analyzed. When these probabilities exceed considerably their reference values obtained by assuming a purely random encounter between the pulsars under consideration, we conclude that the objects may have been gravitationally bound in the past. As a result, we have detected six pulsar pairs (J0543+2329/J0528+2200, J1453-6413/J1430-6623, J2354+6155/J2321+6024, J1915+1009/J1909+1102, J1832-0827/J1836-1008, and J1917+1353/J1926+1648) that are companions in disrupted binary systems with a high probability. Estimates of their kinematic ages and velocities at binary disruption and at the present epoch are provided