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X-ray polarimetry is a unique way to probe geometrical configuration of highly-magnetized accreting neutron stars (X-ray pulsars). GRO J1008−57 is the first transient X-ray pulsar observed at two different flux levels by the Imaging X-ray Polarimetry Explorer (IXPE) during its outburst in November 2022. The polarization properties were found to be independent of the source luminosity, with the polarization degree varying between non-detection to about 15% over the pulse phase. Fitting the phase-resolved spectro-polarimetric data with the rotating vector model allowed us to estimate the pulsar inclination (130 • , which is in good agreement with the orbital inclination), the position angle (75 • ) of the pulsar spin axis, and the magnetic obliquity (∼ 74 • ). This makes GRO J1008−57 the first confidently identified X-ray pulsar as a nearly orthogonal rotator. The results are discussed in the context of the neutron star atmosphere models and theories of pulsars' axis alignment.

In the modern conditions of the post-COVID world, the transformation of the world economy in the framework of the transition to the post-industrial paradigm, and the economy of “knowledge”, the national innovation system (NIS) plays a leading role in the formation of competitive sectors of any given country. Within this setting, the performance of the Russian innovation system significantly lags behind other countries and calls for modernisation based on the modern regulatory tools, policies, and world’s leading trends. The direct import of institutions of foreign innovation systems demonstrates its limited effectiveness due to the incompleteness of institutions and mechanisms for regulating the institutional environment of the Russian economy. One of the generally recognised, leading, and the most “universal” instruments for implementing innovation policy by government institutions is the public procurement of innovation. The analysis of international experience shows that the implementation of the innovation policy via innovative public procurement has a highly heterogeneous landscape even in such a “cohesive” jurisdiction as those represented by the European Union (EU) as far as different types of policy dominate in different countries of the world. There is no clear trend towards the only one mainstream regulatory approach. In this context, the Russian experience demonstrates de facto the absence of any centralised, transparent, and effective policy expressed in such pseudo-innovative procurement as refuelling cartridges or car repairs. This paper identifies the existing institutional failures of the Russian NIS on the example of the regulation of innovative domestic procurement. It proposes ways to modernise the current policy based on the institutional and narrative approaches in order to foster its leading position in the international competition. This article shows the gaps in the literature in institutional governance of innovations and innovation procurement in Russia and points at directions for future research based on narrative economics. Outlining the present knowledge as a foundation for future research in institutional governance of innovations, this article holds implications for both academics and practitioners in the field of the innovation policies and public procurement.

PurposeThe paper aims to present the results of a study aimed at constructing economic and mathematical models used in decision-making in the management of budget procurement of a region, contributing to the efficient use of budget funds. One of the key problems in this area is the assessment of the quality of procurementDesign/methodology/approachOne of the key problems in this area is the assessment of the quality of procurement, the solution of which requires the application of economic and mathematical methods, models, tools and algorithms built into information systems for supporting decision-making. The introduction of these systems brings to a qualitatively new level the system of relations between subjects of budget procurement. The paper analyzes modern publications on the implementation of public procurement and related issues of efficiency (savings) of budgetary funds.FindingsThe indicators on the basis of which the evaluation of the quality of regional procurement is determined are proposed. The architecture of the information system for decision support in the evaluation of procurement quality has been developed. The system has the property of adapting to changes in the state of the environment through the constant accumulation of statistical data characterizing the procurement and adjustment of the parameters of the mathematical model in accordance with them. A mathematical model is built into the control loop that allows ranking the indicators of budget purchases by the degree of their influence on the effective attribute. The role of a functional feature is the quality of budget procurement. The mathematical model is based on the application of the mathematical apparatus of correlation and regression analysis. The impact of each of the factor attributes on the functional attribute has been assessed.Originality/valueThe mathematical model is based on the application of the mathematical apparatus of correlation and regression analysis. The impact of each of the factor attributes on the functional attribute has been assessed. Real statistics are given that characterize budget procurements carried out in retrospect. The coefficients of the linear regression model are determined based on the use of the STATISTICA application software package. The proposed decision support information system with a regression model built into it allows one to make scientifically and quantitatively sound decisions when assessing the quality of budget purchases of a region.

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We report on Imaging X-ray polarimetry explorer (IXPE) observations of the Be-transient X-ray pulsar LS V +44 17/RX J0440.9+4431 made at two luminosity levels during the giant outburst in January–February 2023. Considering the observed spectral variability and changes in the pulse profiles, the source was likely caught in supercritical and subcritical states with significantly different emission-region geometry, associated with the presence of accretion columns and hot spots, respectively. We focus here on the pulse-phase-resolved polarimetric analysis and find that the observed dependencies of the polarization degree and polarization angle (PA) on the pulse phase are indeed drastically different for the two observations. The observed differences, if interpreted within the framework of the rotating vector model (RVM), imply dramatic variations in the spin axis inclination, the position angle, and the magnetic colatitude by tens of degrees within the space of just a few days. We suggest that the apparent changes in the observed PA phase dependence are predominantly related to the presence of an unpulsed polarized component in addition to the polarized radiation associated with the pulsar itself. We then show that the observed PA phase dependence in both observations can be explained with a single set of RVM parameters defining the pulsar’s geometry. We also suggest that the additional polarized component is likely produced by scattering of the pulsar radiation in the equatorial disk wind.

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