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1. Transient and asymmetric dust structures in the TeV-bright nova RS Oph revealed by spectropolarimetry

Author

Nikolov, Y., Luna, G. J. M., Stoyanov, K. A., Borisov, G., Mukai, K., Sokoloski, J. L., and Avramova-Boncheva, A.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract

A long-standing question related to nova eruptions is how these eruptions can lead to the formation of dust despite the ostensibly inhospitable environment for dust within the hot, irradiated ejecta. Novae in systems such as the symbiotic binary RS Oph offers a articularly clear view of some nova shocks and any associated dust production. Here we use spectropolarimetric monitoring of the RS Oph starting two days after its eruption in 2021 Aug. to show that: dust was present in the RS Oph system as early as two days into the 2021 eruption; the spatial distribution of this early dust was asymmetric, with components both aligned with and perpendicular to the orbital plane of the binary; between two and nine days after the start of the eruption, this early dust was gradually destroyed; and dust was again created, aligned roughly with the orbital plane of the binary, more than 80 days after the start of the outburst, most likely as a result of shocks that arose as the ejecta interacted with circumbinary material concentrated in the orbital plane. Modelling of X-rays and very-high energy GeV and TeV emission from RS Oph days to months into the 2021 eruption suggests that collisions between the ejecta and the circumbinary material may have led to shock formation in two regions: the polar - perpendicular to the orbital plane where collimated outflows have been observed after prior eruptions, and a circumbinary torus in the orbital plane. The observations described here indicate that dust formed in approximately the same two regions, supporting the connection between shocks and dust in novae and revealing a very early onset of asymmetry. The spectropolarimetric signatures of RS Oph in the first week into the 2021 outburst indicate: polarized flux across the H{\alpha} emission line and position angle orientation relative to the radio axis are similar to the spectropolarimetric signatures of AGNs., Comment: 9 pages, 10 figures, 1 table, resubmitted to the Astronomy & Astrophysics after the first reviewer's report

Published
2023
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3. (121514) 1999 UJ7: A primitive, slow-rotating Martian Trojan

Author

Borisov, G., Christou, A. A., Colas, F., Bagnulo, S., Cellino, A., and Dell'Oro, A.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Aims. The goal of this investigation is to determine the origin and surface composition of the asteroid (121514) 1999 UJ7, the only currently known L4 Martian Trojan asteroid. Methods. We have obtained visible reflectance spectra and photometry of 1999 UJ7 and compared the spectroscopic results with the spectra of a number of taxonomic classes and subclasses. A light curve was obtained and analysed to determine the asteroid spin state. Results. The visible spectrum of 1999 UJ7 exhibits a negative slope in the blue region and the presence of a wide and deep absorption feature centred around ~0.65 microns. The overall morphology of the spectrum seems to suggest a C-complex taxonomy. The photometric behaviour is fairly complex. The light curve shows a primary period of 1.936 d, but this is derived using only a subset of the photometric data. The asteroid may be in a non-principal axis rotational state, but our observational coverage is insufficient to draw definitive conclusions. Conclusions. Although the observed spectral absorption is wider and deeper, this finding may be compatible with the 0.7 microns spectral feature exhibited by some Ch-type asteroids and could possibly be interpreted as diagnostic of the presence of hydrated minerals. The inferred composition of 1999 UJ7 as a primitive object can be consistent with a volatile-rich object originally accreted beyond the snow line of the solar system and subsequently evolved to reach the inner regions of the solar system., Comment: 8 pages, 5 figures

Published
2018
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4. Rotational variation of the linear polarisation of the asteroid (3200) Phaethon as evidence for inhomogeneity in its surface properties

Author

Borisov, G., Devogèle, M., Cellino, A., Bagnulo, S., Christou, A., Bendjoya, Ph., Rivet, J. -P., Abe, L., Vernet, D., Donchev, Z., Krugly, Yu., Belskaya, I., Bonev, T., Steeghs, D., Galloway, D., Dhillon, V., O'Brien, P., Pollacco, D., Poshyachinda, S., Ramsay, G., Thrane, E., Ackley, K., Rol, E., Ulaczyk, K., Cutter, R., and Dyer, M.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Asteroid (3200) Phaethon is a Near-Earth Apollo asteroid with an unusual orbit that brings it closer to the Sun than any other known asteroid. Its last close approach to the Earth was in mid-December 2017 and the next one will be on October 2026. Previous rotationally time-resolved spectroscopy of Phaethon showed that its spectral slope is slightly bluish, in agreement with its B/F taxonomic classification, but at some rotational phases, it changes to slightly reddish. Motivated by this result we performed time-resolved imaging polarimetry of Phaethon during its recent close approach to the Earth. Phaethon has a spin period of 3.604 hours and we found a variation of the linear polarisation with rotation. This seems to be a rare case in which such variation is unambiguously found, also a consequence of its fairly large amplitude. Combining this new information with the brightness and colour variation, as well as previously reported results from Arecibo radar observations, we conclude that there is no variation of the mineralogy across the surface of Phaeton. However, the observed change in the linear polarisation may be related to differences in the thickness of the surface regolith in different areas or local topographic features., Comment: 5 pages, 2 figures, MNRAS Letters

Published
2018
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5. The phase-polarization curve of asteroid (3200) Phaethon

Author

Devogèle, M., Cellino, A., Borisov, G., Bendjoya, Ph., Rive, J. -P., Abe, L., Bagnulo, S., Christou, A., Vernet, D., Donchev, Z., Belskaya, I., Bonev, T., and Krugly, Yu. N.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

A multi-colour phase-polarization curve of asteroid (3200)~Phaethon has been obtained during the December 2017 apparition by merging measurements taken at the observing station of Calern (France) and at the Rhozen observatory (Bulgaria). All the observations were obtained in the positive polarization branch, the phase angle ranging from 36$^\circ$ to 116$^\circ$. The measured values of linear polarization are among the highest ever observed for a Solar system body. The covered interval of phase angle was not sufficiently extended to derive a firm determination of the $P_{\rm max}$ parameter, but this appears to occur at a phase angle around 130$^\circ$ and reaches more than 45\% of linear polarization. Phaethon is the parent body of the Geminid meteor shower, and the real physical nature of this object (asteroid or comet) has been a long-debated subject. Our polarimetric measurements seem to support the asteroid hypothesis with a phase-polarization curve similar to the asteroid (2)~Pallas, but further observations at smaller phase angles are needed to draw definitive conclusions., Comment: 12 pages, 7 figures

Published
2018
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6. New polarimetric and spectroscopic evidence of anomalous enrichment in spinel-bearing Calcium-Aluminium-rich Inclusions among L-type asteroids

Author

Devogèle, M., Tanga, P., Cellino, A., Bendjoya, Ph., Rivet, J. -P., Surdej, J., Vernet, D., Sunshine, J. M., Bus, S. J., Abe, L., Bagnulo, S., Borisov, G., Campins, H., Carry, B., Licandro, J., McLean, W., and Pinilla-Alonso, N.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Asteroids can be classified into several groups based on their spectral reflectance. Among these groups, the one belonging to the L-class in the taxonomic classification based on visible and near-infrared spectra exhibit several peculiar properties. First, their near-infrared spectrum is characterized by a strong absorption band interpreted as the diagnostic of a high content of the FeO bearing spinel mineral. This mineral is one of the main constituents of Calcium-Aluminum-rich Inclusions (CAI) the oldest mineral compounds found in the solar system. In polarimetry, they possess an uncommonly large value of the inversion angle incompatible with all known asteroid belonging to other taxonomical classes. Asteroids found to possess such a high inversion angle are commonly called Barbarians based on the first asteroid on which this property was first identified, (234)~Barbara. In this paper we present the results of an extensive campaign of polarimetric and spectroscopic observations of L-class objects. We have derived phase-polarization curves for a sample of 7 Barbarians, finding a variety of inversion angles ranging between 25 and 30$^{\circ}$. Spectral reflectance data exhibit variations in terms of spectral slope and absorption features in the near-infrared. We analyzed these data using a Hapke model to obtain some inferences about the relative abundance of CAI and other mineral compounds. By combining spectroscopic and polarimetric results, we find evidence that the polarimetric inversion angle is directly correlated with the presence of CAI, and the peculiar polarimetric properties of Barbarians are primarily a consequence of their anomalous composition., Comment: 31 pages, 21 figures, 5 tables

Published
2018
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7. The 67P/Churyumov-Gerasimenko observation campaign in support of the Rosetta mission

Author

Snodgrass, C., A'Hearn, M. F., Aceituno, F., Afanasiev, V., Bagnulo, S., Bauer, J., Bergond, G., Besse, S., Biver, N., Bodewits, D., Boehnhardt, H., Bonev, B. P., Borisov, G., Carry, B., Casanova, V., Cochran, A., Conn, B. C., Davidsson, B., Davies, J. K., de León, J., de Mooij, E., de Val-Borro, M., Delacruz, M., DiSanti, M. A., Drew, J. E., Duffard, R., Edberg, N. J. T., Faggi, S., Feaga, L., Fitzsimmons, A., Fujiwara, H., Gibb, E. L., Gillon, M., Green, S. F., Guijarro, A., Guilbert-Lepoutre, A., Gutiérrez, P. J., Hadamcik, E., Hainaut, O., Haque, S., Hedrosa, R., Hines, D., Hopp, U., Hoyo, F., Hutsemékers, D., Hyland, M., Ivanova, O., Jehin, E., Jones, G. H., Keane, J. V., Kelley, M. S. P., Kiselev, N., Kleyna, J., Kluge, M., Knight, M. M., Kokotanekova, R., Koschny, D., Kramer, E., López-Moreno, J. J., Lacerda, P., Lara, L. M., Lasue, J., Lehto, H. J., Levasseur-Regourd, A. C., Licandro, J., Lin, Z. Y., Lister, T., Lowry, S. C., Mainzer, A., Manfroid, J., Marchant, J., McKay, A. J., McNeill, A., Meech, K. J., Micheli, M., Mohammed, I., Monguió, M., Moreno, F., Muñoz, O., Mumma, M. J., Nikolov, P., Opitom, C., Ortiz, J. L., Paganini, L., Pajuelo, M., Pozuelos, F. J., Protopapa, S., Pursimo, T., Rajkumar, B., Ramanjooloo, Y., Ramos, E., Ries, C., Riffeser, A., Rosenbush, V., Rousselot, P., Ryan, E. L., Santos-Sanz, P., Schleicher, D. G., Schmidt, M., Schulz, R., Sen, A. K., Somero, A., Sota, A., Stinson, A., Sunshine, J., Thompson, A., Tozzi, G. P., Tubiana, C., Villanueva, G. L., Wang, X., Wooden, D. H., Yagi, M., Yang, B., Zaprudin, B., and Zegmott, T. J.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We present a summary of the campaign of remote observations that supported the European Space Agency's Rosetta mission. Telescopes across the globe (and in space) followed comet 67P/Churyumov-Gerasimenko from before Rosetta's arrival until nearly the end of mission in September 2016. These provided essential data for mission planning, large-scale context information for the coma and tails beyond the spacecraft, and a way to directly compare 67P with other comets. The observations revealed 67P to be a relatively `well behaved' comet, typical of Jupiter family comets and with activity patterns that repeat from orbit-to-orbit. Comparison between this large collection of telescopic observations and the in situ results from Rosetta will allow us to better understand comet coma chemistry and structure. This work is just beginning as the mission ends -- in this paper we present a summary of the ground-based observations and early results, and point to many questions that will be addressed in future studies., Comment: Author prepared version; final published version available at journal. 22 pages

Published
2017
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8. The olivine-dominated composition of the Eureka family of Mars Trojan asteroids

Author

Borisov, G., Christou, A., Bagnulo, S., Cellino, A., Kwiatkowski, T., and Dell'Oro, A.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We have used the XSHOOTER echelle spectrograph on the European Southern Obseratory (ESO) Very Large Telescope (VLT) to obtain UVB-VIS-NIR (ultraviolet-blue (UVB), visible (VIS) and near-infrared (NIR)) reflectance spectra of two members of the Eureka family of L5 Mars Trojans, in order to test a genetic relationship to Eureka. In addition to obtaining spectra, we also carried out VRI photometry of one of the VLT targets using the 2-m telescope at the Bulgarian National Astronomical Observatory - Rozhen and the two-channel focal reducer. We found that these asteroids belong to the olivine-dominated A, or Sa, taxonomic class. As Eureka itself is also an olivine-dominated asteroid, it is likely that all family asteroids share a common origin and composition. We discuss the significance of these results in terms of the origin of the martian Trojan population., Comment: 7 pages, 6 figures, 3 tables

Published
2017
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11. Exceptional outburst of the blazar CTA 102 in 2012: The GASP-WEBT campaign and its extension

Author

Larionov, V. M., Villata, M., Raiteri, C. M., Jorstad, S. G., Marscher, A. P., Agudo, I., Smith, P. S., Acosta-Pulido, J. A., Arévalo, M. J., Arkharov, A. A., Bachev, R., Blinov, D. A., Borisov, G., Borman, G. A., Bozhilov, V., Bueno, A., Carnerero, M. I., Carosati, D., Casadio, C., Chen, W. P., Clemens, D. P., Di Paola, A., Ehgamberdiev, Sh. A., Gómez, J. L., González-Morales, P. A, Griñón-Marín, A., Grishina, T. S., Hagen-Thorn, V. A., Ibryamov, S., Itoh, R., Kopatskaya, E. N., Koptelova, E., Lázaro, C., Larionova, E. G., Larionova, L. V., Manilla-Robles, A., Metodieva, Y., Milanova, Yu. V., Mirzaqulov, D. O., Molina, S. N., Morozova, D. A., Nazarov, S. V., Ovcharov, E., Peneva, S., Ros, J. A., Sadun, A. C., Savchenko, S. S., Semkov, E., Sergeev, S. G., Strigachev, A., Troitskaya, Yu. V., and Troitsky, I. S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

After several years of quiescence, the blazar CTA 102 underwent an exceptional outburst in 2012 September-October. The flare was tracked from gamma-ray to near-infrared frequencies, including Fermi and Swift data as well as photometric and polarimetric data from several observatories. An intensive GASP-WEBT collaboration campaign in optical and NIR bands, with an addition of previously unpublished archival data and extension through fall 2015, allows comparison of this outburst with the previous activity period of this blazar in 2004-2005. We find remarkable similarity between the optical and gamma-ray behaviour of CTA 102 during the outburst, with a time lag between the two light curves of ~1 hour, indicative of co-spatiality of the optical and gamma-ray emission regions. The relation between the gamma-ray and optical fluxes is consistent with the SSC mechanism, with a quadratic dependence of the SSC gamma-ray flux on the synchrotron optical flux evident in the post-outburst stage. However, the gamma-ray/optical relationship is linear during the outburst; we attribute this to changes in the Doppler factor. A strong harder-when-brighter spectral dependence is seen both the in gamma-ray and optical non-thermal emission. This hardening can be explained by convexity of the UV-NIR spectrum that moves to higher frequencies owing to an increased Doppler shift as the viewing angle decreases during the outburst stage. The overall pattern of Stokes parameter variations agrees with a model of a radiating blob or shock wave that moves along a helical path down the jet., Comment: 11 pages, 14 figures, accepted in MNRAS

Published
2016
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12. Broadband Linear Polarization of Jupiter Trojans

Author

Bagnulo, S., Belskaya, I. N., Stinson, A., Christou, A., and Borisov, G. B.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

Trojan asteroids orbit in the Lagrange points of the system Sun-planet-asteroid. Their dynamical stability make their physical properties important proxies for the early evolution of our solar system. To study their origin, we want to characterize the surfaces of Jupiter Trojan asteroids and check possible similarities with objects of the main belt and of the Kuiper Belt. We have obtained high-accuracy broad-band linear polarization measurements of six Jupiter Trojans of the L4 population and tried to estimate the main features of their polarimetric behaviour. We have compared the polarimetric properties of our targets among themselves, and with those of other atmosphere-less bodies of our solar system. Our sample show approximately homogeneous polarimetric behaviour, although some distinct features are found between them. In general, the polarimetric properties of Trojan asteroids are similar to those of D- and P-type main-belt asteroids. No sign of coma activity is detected in any of the observed objects. An extended polarimetric survey may help to further investigate the origin and the surface evolution of Jupiter Trojans., Comment: Accepted for publication on A&A

Published
2015
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13. The physical and dynamical characteristics of the asteroid 4940 Polenov

Author

Vchkova-Bebekovska E., Todorović N., Kostov A., Donchev Z., Borisov G., and Apostolovska G.

Subjects
minor planets, asteroids: individual: 4940 polenov, techniques: photometric, Astronomy, QB1-991
Abstract

The asteroid (1986 QY4) 4940 Polenov is the first Solar system object whose 3D shape is determined using the observations from the newly built Astronomical Station Vidojevica (ASV). Here we present the results of photometric observations for Polenov, gathered from the ASV, and from the Bulgarian National Astronomical Observatory (BNAO) Rozhen, during 2014, 2019 and 2020 apparitions. Polenov is a 17.8km object located in the outer part of the main belt and belongs to the asteroid family Themis. We have determined the lightcurves, the synodic period of 4.161±0.001 h, as well as the solution for the shape and spin axis. Using the lightcurve inversion method, the combination of our lightcurves and the sparse data from ATLAS{HKO and ATLAS-MLO, we also found the sidereal period, indicating a retrograde rotation of the asteroid, with two possible mirrored pole solutions. The ratio of the largest to smallest reecting surface is about 1.4. In addition, we studied the dynamical properties of the asteroid and obtained a long stability time that exceeds 0.4 Gyrs.

Published
2021
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16. Photometric observations and preliminary modeling of type IIb supernova 2011dh

Author

Tsvetkov, D. Yu., Volkov, I. M., Sorokina, E. I., Blinnikov, S. I., Pavlyuk, N. N., and Borisov, G. V.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

CCD UBVRI photometry is presented for type IIb SN 2011dh for about 300 days. The main photometric parameters are derived and the comparison with SNe of similar types is reported. The light curves are similar to those for SN IIb 2008ax, but the initial flash is stronger and very short, and there are humps on the light curves in U and B at the onset of linear decline. Preliminary modeling is carried out, and the results are compared to the quasi-bolometric light curve and to the light curves in UBVRI bands., Comment: 14 pages, 9 figures, submitted to Variable Stars (Peremennye Zvezdy)

Published
2012

17. Rotation-stimulated structures in the CN and C3 comae of comet 103P/Hartley 2 around the EPOXI encounter

Author

Waniak, W., Borisov, G., Drahus, M., and Bonev, T.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

In late 2010 a Jupiter Family comet 103P/Hartley 2 was a subject of an intensive world-wide investigation. On UT October 20.7 the comet approached the Earth within only 0.12 AU, and on UT November 4.6 it was visited by NASA's EPOXI spacecraft. We joined this international effort and organized an observing campaign. The images of the comet were obtained through narrowband filters using the 2-m telescope of the Rozhen National Astronomical Observatory. They were taken during 4 nights around the moment of the EPOXI encounter. Image processing methods and periodicity analysis techniques were used to reveal transient coma structures and investigate their repeatability and kinematics. We observe shells, arc-, jet- and spiral-like patterns, very similar for the CN and C3 comae. The CN features expanded outwards with the sky-plane projected velocities between 0.1 to 0.3 km/s. A corkscrew structure, observed on November 6, evolved with a much higher velocity of 0.66 km/s. Photometry of the inner coma of CN shows variability with a period of 18.32+/-0.30 h (valid for the middle moment of our run, UT 2010 Nov. 5.0835), which we attribute to the nucleus rotation. This result is fully consistent with independent determinations around the same time by other teams. The pattern of repeatability is, however, not perfect, which is understendable given the suggested excitation of the rotation state, and the variability detected in CN correlates well with the cyclic changes in HCN, but only in the active phases. The revealed coma structures, along with the snapshot of the nucleus orientation obtained by EPOXI, let us estimate the spin axis orientation. We obtained RA=122 deg, Dec=+16 deg (epoch J2000.0), neglecting at this point the rotational excitation., Comment: 9 pages, 10 figures, submitted to Astron. Astrophys

Published
2012
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20. Optical Observations of Gamma-Ray Bursts, the Discovery of Supernovae 2005bv, 2005ee, and 2006ak, and Searches for Transients Using the 'MASTER' Robotic Telescope

Author

Lipunov, V. M., Kornilov, V. G., Krylov, A. V., Tyurina, N. V., Belinski, A. A., Gorbovskoy, E. S., Kuvshinov, D. A., Gritsyk, P. A., Antipov, G. A., Borisov, G. V., Sankovich, A. V., Vladimirov, V. V., Vybornov, V. I., and Kuznetsov, A. S.

Subjects
Astrophysics
Abstract

We present the results of observations obtained using the MASTER robotic telescope in 2005 - 2006, including the earliest observations of the optical emission of the gamma-ray bursts GRB 050824 and GRB 060926. Together with later observations, these data yield the brightness-variation law t^{-0.55+-0.05} for GRB 050824. An optical flare was detected in GRB 060926 - a brightness enhancement that repeated the behavior observed in the X-ray variations. The spectrum of GRB 060926 is found to be F_E ~ E^-\beta, where \beta = 1.0+-0.2. Limits on the optical brightnesses of 26 gamma-ray bursts have been derived, 9 of these for the first time. Data for more than 90% of the accessible sky down to $19^m$ were taken and reduced in real time during the survey. A database has been composed based on these data. Limits have been placed on the rate of optical flares that are not associated with detected gamma-ray bursts, and on the opening angle for the beams of gamma-ray bursts. Three new supernovae have been discovered: SN 2005bv (type Ia) - the first to be discovered on Russian territory, SN 2005ee - one of the most powerful type II supernovae known, and SN 2006ak (type Ia). We have obtained an image of SN 2006X during the growth stage and a light curve that fully describes the brightness maximum and exponential decay. A new method for searching for optical transients of gamma-ray bursts detected using triangulation from various spacecraft is proposed and tested., Comment: 30 pages, 18 figures, 9 tables

Published
2007
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21. Asteroid clusters similar to asteroid pairs

Author

Pravec, P., Fatka, P., Vokrouhlický, D., Scheeres, D.J., Kušnirák, P., Hornoch, K., Galád, A., Vraštil, J., Pray, D.P., Krugly, Yu.N., Gaftonyuk, N.M., Inasaridze, R.Ya., Ayvazian, V.R., Kvaratskhelia, O.I., Zhuzhunadze, V.T., Husárik, M., Cooney, W.R., Gross, J., Terrell, D., Világi, J., Kornoš, L., Gajdoš, Š., Burkhonov, O., Ehgamberdiev, Sh.A., Donchev, Z., Borisov, G., Bonev, T., Rumyantsev, V.V., and Molotov, I.E.

Published
2018
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22. MASTER: The Mobile Astronomical System of Telescope-Robots

Author

Lipunov, V. M., Krylov, A. V., Kornilov, V. G., Borisov, G. V., Kuvshinov, D. A., Belinsky, A. A., Kuznetsov, M. V., Potanin, S. A., Antipov, G. A., Tyurina, N. V., Gorbovskoy, E. S., and Chilingaryan, I.

Subjects
Astrophysics
Abstract

We present the first russian robot-telescope designed to make prompt observations of gamma-ray bursts (http://observ.pereplet.ru). The telescopes are near Moscow. The system of telescopes with prompt pointing rates connects to the internet. The main parameters are the following: Richter-Slefogt system telescope (355 mm, f/d=2.4); Richter-Slefogt system telescope (200mm, f/d=2.4); Flugge system telescope (280mm, f/d=2.5); TV-camera with 20x40 degree objective; Two CCD cameras (Pictor 416); One CCD Apogee Camera AP16E. The type of mount is German with 8 grad/sec slew rate. MASTER images stars down to 19 magnitude in a 1 min exposure covering 6 square degrees., Comment: 3 pages, 2 figures

Published
2004
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24. Precise measurement of Higgs decay rate into WW* at future e^+e^- Linear Colliders

Author

Borisov, G. and Richard, F.

Subjects
High Energy Physics - Phenomenology
Abstract

Assuming a SM or MSSM scenario, one expects a light Higgs boson which could be studied in great detail with a LC operating at \sqrt s>m_h+m_Z. In the TESLA scenario, with 500 fb^-1 accumulated at \sqrt s = 350 GeV, about 10^5 hZ events could be produced through the Higgstrahlung process. At a future LC with a \sim 1 cm beam-pipe radius and a thin Si detector there will be excellent separation between the various flavours. With the high statistics available it will thus become possible to measure the various branching ratios with a few % error. Typically one expects 8 % precision on BR(h\to\bar cc), 6 % on BR(h\to gg) and \sim 1 % on \sigma(hZ) x BR(h\to\bar bb) access to BR(h\to WW^*) and, as explained in section 3, this measurement can give access to the Higgs total decay width and therefore to all partial widths. In particular one can precisely measure \Gamma(h\to\bar bb) and \Gamma(h\to\tau^+\tau^-) which have a high sensitivity to MSSM effects\cite{gunion} and therefore allow an essential test of the Higgs sector. If m_A < 1 TeV, it becomes possible to measure a significant deviation and, within MSSM, to give an indirect estimate of m_A thus extending the effective sensitivity above the discovery domain of LHC. In the following section we describe a detailed analysis on the measurement of BR(h\to WW^*)., Comment: 12 pages

Published
1999

25. Study of eta pi- production by pions in the Coulomb field

Author

VES collaboration, Amelin, D. V., Berdnikov, E. B., Bityukov, S. I., Borisov, G. V., Dzhelyadin, R. I., Dorofeev, V. A., Ekimov, A. V., Gouz, Yu. P., Konoplyannikov, A. K., Karyukhin, A. N., Kachaev, I. A., Khokhlov, Yu. A., Likhoded, S. A., Matveyev, V. D., Ostankov, A. P., Ryabchikov, D. I., Solovianov, O. V., Solodkov, A. A., Starchenko, E. A., Vishnevsky, N. K., Vlassov, E. V., Zaitsev, A. M., Sekhniaidze, G. G., and Tskhadadze, E. G.

Subjects
High Energy Physics - Experiment
Abstract

The production of eta pi - system at low mass by the pi- beam in the Coulomb field of Be nuclei was studied. The cross section of the reaction pi- Be --> eta pi- Be was compared to the experimental data on the decay eta --> pi+ pi- gamma and to the theoretical predictions., Comment: 11 pages, 5 figures, gzipped tar file

Published
1998

31. Photometry and shape modeling of Mars crosser asteroid (1011) Laodamia

Author

Apostolovska G., Donchev Z., Kostov A., Ivanova V., Borisov G., and Bilkina B.

Subjects
minor planets, asteroids: individual: 1011 Laodamia, techniques: photometric, Astronomy, QB1-991
Abstract

An analysis of photometric observations of Mars crosser asteroid 1011 Laodamia conducted at Bulgarian National Astronomical Observatory Rozhen over a twelve year interval (2002, 2003, 2004, 2006, 2007, 2008, 2011, 2012 and 2013) is made. Based on the obtained lightcurves the spin vector, sense of rotation, and preliminary shape model of (1011) Laodamia have been determined using the lightcurve inversion method. The aim of this investigation is to increase the set of asteroids with known spin and shape parameters and to contribute in improving the model in combination with other techniques and sparse data produced by photometric asteroid surveys such as Pan-STARRS or GAIA.

Published
2014
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38. Personal mobility as an occupational health predictor in late age: research results and their use in the development of training programmes

Author

Sergeeva, T. B., Glukhanyuk, N. S., Pecherkina, A. A., and Borisov, G. I.

Subjects
PSYCHOLOGICAL PREDICTORS, PERSONAL MOBILITY, TRAINING PROGRAMMES, OCCUPATIONAL HEALTH, PSYCHOLOGICAL WELL-BEING, LATE AGE
Abstract

Introduction. Pedagogical and psychological science and practice emphasize the importance of various modes of study for maintaining the health and psychological well-being of people in late age. Determining occupational health predictors makes it possible to predict adequate methods for including older people in the educational environment and develop effective learning technologies. The research purpose is to detail the relationship between occupational health in late age and personal mobility as its integral predictor. Materials and methods. The empirical study involved 355 residents of Yekaterinburg and the Sverdlovsk region (Russian Federation) aged 50 to 80. Three comparison groups were identified: non-working pensioners, working pensioners, a comparison group – working people of pre-retirement age. A complex of 15 psychodiagnostic methods was implemented, describing as follows: 1) personal mobility as an individual property, life strategy, readiness for mobile behavior; 2) the emotional, reflective, value-motivational, activity components of occupational health; 3) psychological well-being. The methods of descriptive and comparative statistics, the correlation, cluster, factorial, regression, dispersion analysis were used for data processing. Results. A three-component structure of occupational health at a late age and an eight-component structure of personal mobility are described (the share of explained dispersion of factor models is 0.42 and 0.51, respectively). The initial theoretical model of contingency between the occupational health of older people and personal mobility as its predictor was empirically verified and clarified: a list of mobility characteristics was determined that affects each of the three components of occupational health – the activity, emotional-reflexive components and psychological well-being (the coefficient of determination of regression models is 0.42, 0.29 and 0.28 respectively). Discussion and conclusions. The research results made it possible to recommend the principles for developing technologies for teaching to preserve occupational health: complexity and universality, reliance on the free choice of the content and modes of study by an older person. Methods that meet these principles were defined: the formation of personal mobility as an integral occupational health predictor, work with life experience, dynamic learning, the use of reflection as a development mechanism in late age. © 2022 LLC Ecological Help. All rights reserved.

Published
2022

39. Физическое и психологическое здоровье как ресурс психологического благополучия педагогов позднего возраста

Author

Borisov, G. I.

Subjects
ПСИХОЛОГИЧЕСКОЕ ЗДОРОВЬЕ, TEACHERS, ПОЗДНИЙ ВОЗРАСТ, ПСИХОЛОГИЧЕСКОЕ БЛАГОПОЛУЧИЕ, PSYCHOLOGICAL HEALTH, ФИЗИЧЕСКОЕ ЗДОРОВЬЕ, PSYCHOLOGICAL WELL-BEING, LATE AGE, PHYSICAL HEALTH, ПЕДАГОГИ
Abstract

В работе рассматривается физическое и психологическое здоровье как ресурс психологического благополучия педагогов позднего возраста. Проведено эмпирическое исследование. В нем приняли участие 309 преподавателей. Методиками исследования выступили шкала психологического благополучия К. Рифф (в адаптации Т. Д. Шевеленковой, Т. П. Фесенко) и опросник оценки качества жизни SF-36. Данные обрабатывались при помощи критерия корреляции Спирмена. В результате было установлено позитивное влияние физического и психологического здоровья на психологическое благополучие и его характеристики у педагогов позднего возраста. The paper considers physical and psychological health as a resource for psychological well-being of older teachers. An empirical study of the direction to determine the influence of physical and psychological health on the psychological well-being of older teachers was carried out. The study involved 309 older teachers. The research methods were the scale of psychological well-being by С. Riff (adapted by T. D. Shevelenkova, T. P. Fesenko) and the questionnaire for assessing the quality of life SF‑36. The data were processed using Spearman’s correlation test. As a result, a positive influence of physical and psychological health on psychological well-being and its characteristics in older teachers was established. Исследование выполнено при финансовой поддержке РФФИ в рамках научного проекта № 20‑013‑00790 «Преодоление кризиса утраты профессиональной деятельности у педагогов в период поздней зрелости».

Published
2022

40. RESOURCES FOR THE PSYCHOLOGICAL WELL-BEING OF PEOPLE OF LATE ADULTHOOD

Author

Borisov, G. I.

Subjects
RESOURCES, GERONTOGENESIS, РЕСУРСЫ, ПОЗДНЯЯ ЗРЕЛОСТЬ, ПСИХОЛОГИЧЕСКОЕ БЛАГОПОЛУЧИЕ, ГЕРОНТОГЕНЕЗ, PSYCHOLOGICAL WELL-BEING, LATE MATURITY
Abstract

Psychological well-being in late adulthood determines the success of the gerontogenesis process. This determines the relevance of the search for resources that provide psychological well-being in late adulthood. Based on the diversity of psychological changes in late adulthood, we have identified four blocks of resources for the psychological well-being of people of late maturity: psychophysiological, emotional-volitional, reflexive-regulatory, value-motivational. The article describes the design of an empirical study of the impact of these resources on the psychological well-being of people of late maturity. Психологическое благополучие в поздней зрелости детерминирует успешность процесса геронтогенеза. Это обуславливает актуальность поиска ресурсов, обеспечивающих психологическое благополучие в поздней зрелости. Исходя из разнообразия психологических изменений в поздней зрелости, мы выделили четыре блока ресурсов психологического благополучия людей поздней зрелости: психофизиологический, эмоционально-волевой, рефлексивно-регуляционный, ценностно-мотивационный. В статье описан дизайн эмпирического исследования влияния данных ресурсов на психологическое благополучие людей поздней зрелости. При поддержке Программы стратегического академического лидерства «Приоритет 2030» Министерства науки и высшего образования Российской Федерации.

Published
2022

41. Psychological Well-Being in the Elderly People

Author

Borisov, G. I., Dorogina, O. I., Zinnatova, M. V., and Lavrova, M. A.

Subjects
СТРАТЕГИИ ДОСТИЖЕНИЯ БЛАГОПОЛУЧИЯ, МАРКЕРЫ ПСИХОЛОГИЧЕСКОГО БЛАГОПОЛУЧИЯ, MARKERS OF PSYCHOLOGICAL WELL-BEING, ЗДОРОВЬЕ, WELL-BEING, PSYCHOLOGICAL WELL-BEING, ELDERLY PEOPLE, ПОЖИЛЫЕ, ПСИХОЛОГИЧЕСКАЯ ПОДДЕРЖКА, STRATEGIES OF WELL-BEING, ПСИХОЛОГИЧЕСКОЕ БЛАГОПОЛУЧИЕ, HEALTH, БЛАГОПОЛУЧИЕ, PSYCHOLOGICAL SUPPORT
Abstract

Оригинал статьи получен 01 июня 2022. Исправленная статья принята 02 июня 2022. Первая публикация онлайн July 20, 2022. В статье представлены материалы круглого стола, прошедшего в Уральском федеральном университете имени первого Президента России Б. Н. Ельцина (г. Екатеринбург) 2 апреля 2022 г. На заседании обсуждались вопросы психологического благополучия лиц пожилого возраста: методологические основания исследования, стратегии достижения, связь с физиологическим и психологическим здоровьем, психологическая поддержка и др. On April 2, 2022, Ural Federal University (Yekaterinburg) hosted a round-table conference, devoted to discussing issues of elderly people’ psychological well-being: methodological foundations of research of psychological well-being, strategies for achieving psychological well-being, the relationship of psychological well-being with physiological and psychological health, features of psychological support for the elderly.

Published
2022

42. Features of the profession loss crisis in older teachers

Author

Symanyuk, E. E., Borisov, G. I., Pecherkina, A. A., and Saveliev, V. V.

Subjects
EXPERIENCING A CRISIS, TEACHERS, ПОЗДНИЙ ВОЗРАСТ, КРИЗИС УТРАТЫ ПРОФЕССИИ, CRISIS OF PROFESSIONAL DEVELOPMENT, PROFESSION LOSS CRISIS, КРИЗИС ПРОФЕССИОНАЛЬНОГО РАЗВИТИЯ, ПЕРЕЖИВАНИЕ КРИЗИСА, LATE AGE, ПЕДАГОГИ
Abstract

Introduction. The relevance of the current research in the features of the profession loss crisis among older teachers is due to the need to develop the methods of psychological support for their professional development in the conditions of growing demands on the educational process. The aim of the study is to identify the features of the profession loss crisis among older teachers. In the course of the study, the authors put forward the following hypotheses. The features of the profession loss crisis include two scenarios, which are reflected in the psychological state of teachers and their attitude towards their own profession. The positive scenario is characterized by physical and psychological health, hardiness and psychological well-being, while the negative scenario is characterised by deterioration in physical and mental health, reduced hardiness and psychological well-being. Methodology and research methods. The methodological basis for the study was the concept of professional development by E. F. Zeer and E. E. Symaniuk, as well as the approaches to examining the psychological characteristics of the crisis of late age; psycho-aging changes at a later age; stages of professional development; features of experiencing crises. The study involved 956 teachers working in educational organisations of the Sverdlovsk region (58 men and 898 women). The average age of the respondents was 57.9 years. The features of the profession loss crisis were determined using the biographical method, which allowed the authors to consider the dynamic process of professional development and highlight the psychological characteristics of the crisis based on content analysis. The biographical questionnaire contained questions aimed at identifying general social and professional information, determining the characteristics of options, professional activities, retirement and plans for future life, as well as determining the success of a professional biography. The following methods were used: test of hardiness in the adaptation of E. N. Osin and E. I. Rasskazova; method of quality-of-life SF-36; T. V. Kornilova’s new questionnaire of tolerance to uncertainty; scale of psychological well-being by K. Riff as adapted by T. D. Shevelenkova, P. P. Fesenko; questionnaire by K. Zamfir “Motivation of professional activity” in the modification of A. A. Rean. Data processing was carried out in the RStudio program. To highlight the options for the course of the crisis, cluster analysis was used. Welch’s t-test was applied to compare the groups with each other. The one-sample Student’s t-test was used to compare groups with standard indicators. Results. It was revealed that the profession loss crisis can proceed according to two scenarios, each of which has its own characteristics. In a positive scenario (about 3/4 of cases), the indicators of physical and psychological health, vitality and psychological well-being do not differ from the normative values. At the same time, teachers generally have a good attitude towards their profession and have plans to continue working in profession and learning something new. In the negative scenario of the crisis, the indicators of resilience and psychological well-being are at the lower limit of the norm, and the indicators of physical and mental health are significantly lower than the norm. Teachers are much more likely to note disappointment in the profession and, in general, have a more negative attitude towards it than the representatives of the positive group. Among them, there are significantly more of those who plan to leave the profession and fewer of those who plan to stay in the profession and learn something new. Scientific novelty consists in the enrichment of psychological science with knowledge about the features of the profession loss crisis among older teachers working at different levels of education in the context of the professional development of the individual. Practical significance. The presented results can be employed in educational organisations to develop programmes for the prevention of the profession loss crisis among teachers and recommendations for teachers of late maturity to maintain their active professional longevity. Введение. Актуальность исследования особенностей кризиса утраты профессии у педагогов позднего возраста обусловлена необходимостью разработки методов психологического сопровождения их профессионального развития в условиях нарастающих требований к образовательному процессу. Цель исследования заключается в выявлении особенностей кризиса утраты профессии у педагогов позднего возраста. В рамках исследования были поставлены следующие гипотезы. К особенностям кризиса утраты профессии относятся два сценария его протекания, которые отражаются на психологическом состоянии педагогов и их отношении к собственной профессии. Позитивный сценарий характеризуется физическим и психологическим здоровьем, жизнестойкостью и психологическим благополучием, негативный – ухудшением физического и психического здоровья, снижением жизнестойкости и психологического благополучия. Методология, методы и методики. Методологическими основаниями исследования выступила концепция профессионального развития Э. Ф. Зеера и Э. Э. Сыманюк, а также подходы к рассмотрению психологических характеристик кризиса позднего возраста, психовозрастных изменений в позднем возрасте, стадий профессионального развития, особенностей переживания кризисов. В исследовании участвовало 956 педагогов, работающих в организациях системы образования Свердловской области (58 мужчин и 898 женщин). Средний возраст респондентов составил 57,9 года. Особенности протекания кризиса утраты профессии определялись при помощи биографического метода, который позволяет рассмотреть динамический процесс профессионального развития и выделить на основе контент-анализа психологические особенности кризиса. Биографическая анкета содержала вопросы, направленные на выявление общей социально-профессиональной информации, определение особенностей оптации, профессиональной деятельности, ухода на пенсию и планов дальнейшей жизни, а также на установление успешности профессиональной биографии. Также использовались стандартизированные психологические методики: тест жизнестойкости в адаптации Е. Н. Осина, Е. И. Рассказовой; методика качества жизни SF-36; новый опросник толерантности к неопределенности Т. В. Корниловой; шкала психологического благополучия К. Рифф в адаптации Т. Д. Шевеленковой, П. П. Фесенко; опросник К. Замфир «Мотивация профессиональной деятельности» в модификации А. А. Реана. Обработка данных осуществлялась в программе RStudio. Для выявления особенностей кризиса утраты профессии был использован кластерный анализ. Для сравнения групп между собой был использован t-критерий Уэлча. Для сравнения групп с нормативными показателями был использован одновыборочный t-критерий Стьюдента. Результаты. Выявлено, что кризис утраты профессии может протекать по двум сценариям, каждый из которых обладает своими особенностями. При позитивном сценарии (около 3/4 случаев) показатели физического и психологического здоровья, жизнестойкости и психологического благополучия не отличаются от нормативных значений. При этом педагоги в целом хорошо относятся к своей профессии и имеют в планах продолжение работы по ней и обучение чему-то новому. При негативном сценарии протекания кризиса показатели жизнестойкости и психологического благополучия находятся на нижней границе нормы, а показатели физического и психического здоровья значимо ниже нормативных. Педагоги намного чаще отмечают разочарование в профессии и в целом относятся к ней более негативно, чем представители позитивной группы. Среди них значимо больше тех, кто планирует уход из профессии, и меньше тех, кто планирует остаться в профессии и учиться чему-то новому. Научная новизна состоит в обогащении психологической науки знаниями об особенностях кризиса утраты профессии у педагогов позднего возраста в контексте профессионального развития личности. Практическая значимость. Представленные результаты могут быть использованы в образовательных организациях для разработки программ профилактики кризиса утраты профессии у педагогов и рекомендаций для педагогов позднего возраста по сохранению своего активного профессионального долголетия.

Published
2022

48. Strategies for Coping the Loss of Profession of Late Age Teachers

Author

Symanyuk, E. E., Borisov, G. I., Pecherkina, A. A., and Saveliev, V. V.

Subjects
TEACHERS, ДЕСТРУКТИВНАЯ СТРАТЕГИЯ, PEDAGOGICAL ACTIVITY, ПОЗДНИЙ ВОЗРАСТ, ПЕДАГОГИЧЕСКАЯ ПСИХОЛОГИЯ, PEDAGOGICAL PSYCHOLOGY, DESTRUCTIVE STRATEGY, ПЕДАГОГИ, STRATEGIES FOR OVERCOMING THE CRISIS, ПСИХОЛОГИЯ, CONSTRUCTIVE STRATEGY, КРИЗИС УТРАТЫ ПРОФЕССИИ, КОНСТРУКТИВНАЯ СТРАТЕГИЯ, ПРОФЕССИОНАЛЬНОЕ РАЗВИТИЕ, СТРАТЕГИИ ПРЕОДОЛЕНИЯ КРИЗИСА, LATE AGE, ПЕДАГОГИЧЕСКАЯ ДЕЯТЕЛЬНОСТЬ, ПЕДАГОГИЧЕСКАЯ ПСИХОЛОГИЯ ВЗРОСЛЫХ, LOSS OF PROFESSION CRISIS
Abstract

Приводятся результаты исследования, посвященные определению стратегий преодоления кризиса утраты профессии у педагогов позднего возраста. В исследовании приняли участие 387 педагогов, работающих в школах г. Екатеринбурга, средний возраст - 57,8 лет. The article presents the results of a study devoted to the definition of strategies for overcoming the crisis of loss of profession among older teachers. The study involved 387 teachers working in schools in Ekaterinburg, the average age is 57,8 years.

Published
2021

49. Personal Mobility and Life Strategies in Later Age: Research Result

Author

Sergeeva, T. B., Glukhaniuk, N. S., and Borisov, G. I.

Subjects
ТИПЫ ЖИЗНЕННЫХ СТРАТЕГИЙ, TYPES OF LIFE STRATEGIES, PERSONAL MOBILITY, ЛИЧНОСТНАЯ МОБИЛЬНОСТЬ, ПОЗДНИЙ ВОЗРАСТ, READINESS FOR MOBILE BEHAVIOR, ГОТОВНОСТЬ К МОБИЛЬНОМУ ПОВЕДЕНИЮ, LATER AGE
Abstract

Статья поступила в редакцию 07.12.2020 г. Статья посвящена проблеме построения жизненной стратегии в позднем возрасте. Описаны три типа жизненных стратегий в зависимости от уровня личностной мобильности субъекта. В эмпирическом исследовании сопоставлены характеристики людей с низко-, средне- и высокомобильной стратегиями. Сделан вывод, что предпосылками выбора высокомобильной жизненной стратегии являются развитые когнитивные ресурсы и обучаемость, выраженная мотивация к освоению внешних и внутренних изменений, высокий уровень биографической рефлексии. The article is devoted to the problem of building a life strategy in later age. Three types of life strategy are described, depending on the level of personal mobility of the subject. The empirical study compares the characteristics of people with low-, medium- and high-mobility strategies. It is concluded that the prerequisites for choosing a highly mobile life strategy are developed cognitive resources and learning ability, a strong motivation to master external and internal changes, and a high level of biographical reflection. Исследование выполнено при финансовой поддержке РФФИ в рамках научного проекта № 19-013-00431 «Личностная мобильность как предиктор сохранения профессионального здоровья в пожилом возрасте».

Published
2021

50. Психологическое благополучие людей в период поздней зрелости

Author

Elvira E. Symaniuk, E. E., Borisov, G. I., Sergeeva, T. B., Pecherkina, A. A., and Obvintseva, O. V.

Subjects
ПОЗДНЯЯ ВЗРОСЛОСТЬ, СУБЪЕКТНОСТЬ, SUCCESSFUL AGING, AGENCY, УСПЕШНОЕ СТАРЕНИЕ, СТРАТЕГИИ АДАПТАЦИИ, ПСИХОЛОГИЧЕСКОЕ БЛАГОПОЛУЧИЕ, PSYCHOLOGICAL WELL-BEING, LATE ADULTHOOD, ADAPTATION STRATEGIES
Abstract

Original manuscript received March 20, 2021. Revised manuscript accepted August 16, 2021. First published online October 25, 2021. There is a need to find resources for successful aging. So one of the significant personal and psychological characteristics reflecting the process of successful aging is psychological well-being. The purpose of study is to determine the personal factors of the psychological well-being of late adulthood people. The study involved 100 people at the age from 56 to 75 years: 31 men, 69 women. The following methods were used: the scale of psychological well-being by C. Ryff, the Big Five Personality Test by R. McCrae, the Coping Strategy Indicator by D. Amirkchan, The Personal Views Survey III-R by S. Muddi, the method of diagnosing the type of behavioral activity by L. I. Wasserman and N. V. Gumenyuk, the Life Orientation Test by C. Carver and M. Scheier, questionnaire on the socio-professional qualities definition of the subjects. The study identified the factors for achieving psychological well-being by elderly people such as Agency, Attitude to the world, Strategy for adaptation to old age, Meaning of life, Value. Существует потребность в поиске ресурсов, обеспечивающих успешное старение. Так, одной из значимых личностно-психологических характеристик, отражающих процесс успешного старения, является психологическое благополучие. Цель исследования заключалась в определении факторов достижения психологического благополучия людьми позднего возраста. В исследовании приняли участие 100 человек в возрасте от 56 до 75 лет: 31 мужчина, 69 женщин. Использовались следующие методики: шкала психологического благополучия К. Рифф, пятифакторный личностный опросник Р. Мак-Крае и П. Коста, опросник копинг-стратегий Д. Амирхана, тест жизнестойкости С. Мадди, методика диагностики типа поведенческой активности Л. И. Вассермана и Н. В. Гуменюка, тест диспозиционного оптимизма Ч. Карвера и М. Шейера, анкета по определению социально-профессиональных качеств испытуемых. В исследовании выявлены факторы достижения психологического благополучия людьми пожилого возраста, такие как субъектность, отношение к миру, стратегия адаптации к старости, смысл жизни, ценность. The study was carried out with the financial support of the Russian Foundation for Basic Research in the framework of the scientific project No. 19–013–00431 “Personal Mobility as a Means of Predicting and Maintaining Professional Health in Old Age.”

Published
2021

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