Flux density measurements of GPS candidate pulsars at 610 MHz using interferometric imaging technique

We conducted radio interferometric observations of six pulsars at 610 MHz using the Giant Metrewave Radio Telescope (GMRT). All these objects were claimed or suspected to be the gigahertz-peaked spectra (GPS) pulsars. For a half of the sources in our sample the interferometric imaging provides the only means to estimate their flux at 610 MHz due to a strong pulse scatter-broadening. In our case, these pulsars have very high dispersion measure values and we present their spectra containing for the first time low-frequency measurements. The remaining three pulsars were observed at low frequencies using the conventional pulsar flux measurement method. The interferometric imaging technique allowed us to re-examine their fluxes at 610 MHz. We were able to confirm the GPS feature in the PSR B1823$-$13 spectrum and select a GPS candidate pulsar. These results clearly demonstrate that the interferometric imaging technique can be successfully applied to estimate flux density of pulsars even in the presence of strong scattering.Comment: 7 pages, 3 tables, 5 figures, accepted for publication in MNRA

Gigahertz-peaked spectra pulsars and thermal absorption model

We present the results of our radio interferometric observations of pulsars at 325 MHz and 610 MHz using the Giant Metrewave Radio Telescope (GMRT). We used the imaging method to estimate the flux densities of several pulsars at these radio frequencies. The analysis of the shapes of the pulsar spectra allowed us to identify five new gigahertz-peaked spectra (GPS) pulsars. Using the hypothesis that the spectral turnovers are caused by thermal free-free absorption in the interstellar medium, we modeled the spectra of all known objects of this kind. Using the model, we were able to put some observational constrains on the physical parameters of the absorbing matter, which allows us to distinguish between the possible sources of absorption. We also discuss the possible effects of the existence of GPS pulsars on future search surveys, showing that the optimal frequency range for finding such objects would be from a few GHz (for regular GPS sources) to possibly 10 GHz for pulsars and radio-magnetars exhibiting very strong absorption.Comment: Accepted for publication in ApJ, 28 pages, 8 figure

Flux-density spectral analysis for several pulsars and two newly-identified gigahertz-peaked spectra

In this paper we present results from flux density measurements for 21 pulsars over a wide frequency range, using the Giant Metrewave Radio Telescope (GMRT) and the Effelsberg telescope. Our sample was a set of mostly newly discovered pulsars from the selection of candidates for gigahertz-peaked spectra (GPS) pulsars. Using the results of our observations along with previously published data, we identify two new GPS pulsars. One of them, PSR J1740+1000, with dispersion measure of 24 pc cm$^{-3}$, is the first GPS pulsar with such a low DM value.We also selected several strong candidates for objects with high frequency turnover in their spectra which require further investigation.We also revisit our source selection criteria for future searches for GPS pulsars.Comment: 10 pages, 2 tables, 9 figures, accepted for publication in MNRA

Modelling of the radio spectrum evolution in the binary pulsar B1259−-63

In this paper we give the first attempt to model the evolution of the spectrum of PSR B1259$-$63 radio emission while the pulsar orbits the companion Be star. As suggested by Kijak et al. (Mon. Not. R. Astron. Soc. 418:L114, 2011a) this binary system can be useful in understanding the origin of the gigahertz-peaked spectrum of pulsars. The model explains, at least qualitatively, the observed alterations of the spectral shape depending on the orbital phases of this pulsar. Thus, our results support the hypothesis that the external factors have a significant impact on the observed radio emission of a pulsar. The model can also contribute to our understanding of the origin of some non-typical spectral shapes(e.g. flat or broken spectra).Comment: 9 pages, 2 tables, 3 figure

О нормотворческой функции языка СМИ (на примере названий женщин по профессии, должности и званию)

The author considers process to increase the quantity of vocational feminine forms in contemporary Russian language, especially in Russian press. This paper presents Russian vocational feminine forms with feminine suffixes (e.g., -ка, -ша, -иха)

Stereotyp kobiety w skrzydlatych słowach języka rosyjskiego

В настоящей статье даётся короткий анализ крылатых слов как одного из источников языковых стереотипов, касающихся женщины в русском языке. Исходной точкой анализа является само понятие языкового стереотипа и крылатого выражения. Стереотип женщины обсуждается здесь на основе избранных (наиболее известных носителям языка) крылатых выражений русского языка, которые могут давать так положительную, как и отрицательную характеристику женщины. Языковые проблемы указаны на фоне общественной ситуации в современной России, особенно - на фоне проблемы дискриминации женщин

Spectroscopic Characterization of i-motif Forming c-myc Derived Sequences Double-Labeled with Pyrene

In current studies we use the oligonucleotides based on c-myc sequence: CCC CAC CCT CCC CAC CCT CCC C (cmyc22) and CCC CAC CCT CCC CAC CCT CCC CA (cmyc22A) functionalized by pyrene moieties at both termini. Results of the circular dichroism (CD), UV absorption melting experiments, and steady-state fluorescence measurements of pyrene-modified i-motifs as well as their unlabeled precursors are presented and discussed here. The pyrene labels have a remarkable influence on i-motif stability which was deduced from CD spectra and confirmed by UV melting experiments. Both probes emit fluorescence band of pyrene monomer with intensity decreasing upon pH lowering. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s10895-013-1184-z) contains supplementary material, which is available to authorized users

O nieporozumieniach komunikacyjnych na przykładzie nazw zawodowych kobiet (na materiale języka polskiego i rosyjskiego)

The author considers process to increase the quantity of vocational feminine forms in contemporary Russian and Polish languages, especially in press and Internet, because for a few years reactivation these forms in both languages is observed. This paper refers problem of disagreements in communication, which are caused by using vocational feminine names in masculine or feminine gender (e.g., masculine forms in general meanings: Так я ведь женат на бизнесмене; Машинист Степанов женился на начальнике станции; Dyrekcja szkoły podstawowej w Gardnie zatrudni na stanowisko nauczycieli, polonistę i muzyka, najchętniej małżeństwo). This problem in case of feminine gender is observed too and in this article the author gives examples this phenomenon.Настоящая статья является попыткой представить проблему коммуникационных недоразумений на примере названий женщин по профессии в польском и русском языках. Выбор языков не случаен, поскольку именно в исследуемых двух языках наблюдается рост названий женщин по профессии в грамматическом женском роде, что ведёт как к разъяснению коммуникации, так и к её затемнению. Следовательно, главной проблемой, затрагиваемой в настоящей статье является влияние грамматической категории рода на ясность высказывания