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Information × Registration Number 0226U000134, (0125U002903) , R & D reports Title Probing of diffuse interstellar gas in decameter range using different types of radio emission popup.stage_title Проведення спостережень обраних пульсарів на радіотелескопі УРАН-2. Обробка отриманих даних і обробка архівних даних із радіотелескопу УТР-2. Визначення характеристик середовища за даними затримки імпульсів у міжзоряній плазмі. Head Vasylkivskyi Yevhen V., Кандидат фізико-математичних наук Registration Date 05-01-2026 Organization Radio Astronomical Institute of the National Academy of Sciences of Ukraine popup.description1 The aim of this project is the observational testing of new methods for interstellar gas diagnosing by simultaneously observiation of several types of radio emission and by analyzing the same data set. Highly sensitive studies of interstellar medium in direction towards a given sample of pulsars will be performed. The characteristics of diffuse interstellar gas such as dispersion measures, emission measures, electron densities, electron temperatures will be obtained by processing the obtained data sets. A cross-correlation analysis of characteristics of the same medium, which manifest themselves differently in different types of radio emission, will allow us to clarify the physical parameters of this medium, to estimate the contribution of cold plasma to the total electron density on the line of sight. A method for clarifying the physical parameters of galactic HII regions lying on the line of sight in direction of pulsars, using the dispersion measure delays inside the HII regions, will also be proposed and investigated. popup.description2 During the first stage of the project, a sample of pulsars was compiled based on several parameters – dispersion measures, distances, and galactic coordinates. Corresponding weekly observation sessions have been carried out at the URAN-2 radio telescope. The radio emissions from a number of pulsars have been detected – both those within the galactic plane and those at high latitudes, with different dispersion measures and periods. From the observed dispersion measures, the electron density values on the line of sight in the directions of these pulsars were obtained. The electron densities obtained from the pulse characteristics reflect the integrated concentration of electrons over the entire distance from the observer to the pulsar in both main phase states of the interstellar medium – in relatively cold diffuse clouds and in hotter intercloud plasma. The second component of this stage of project was experimental studies of pulsars whose line sight crosses the HII regions. During the reporting period, both positional and transit observations of pulsars lying in the line of sight in direction towards three known HII regions – “California”, “Rosetta”, “Snowflake”, were carried out (the culmination time of these HII regions corresponded to the period of the minimum daily level of interference). During the data processing, the above-mentioned HII regions were detected in absorption against the Galactic background, but the pulsars emission has not yet been detected. In the next stage, it is planned to significantly increase the integration time for each pulsar through appropriate observations. This, among other things, will allow us to search the individual pulses in observational data. Product Description popup.authors Ihor P. Kravtsov Yevhen V. Vasylkivskyi popup.nrat_date 2026-01-05 Close