BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Mathematical aspects of the nuclear glory phenomenon: from backwar d focusing to Chebyshev polynomials DTSTART;VALUE=DATE-TIME:20161014T101500Z DTEND;VALUE=DATE-TIME:20161014T103500Z DTSTAMP;VALUE=DATE-TIME:20260814T163101Z UID:indico-contribution-108-749@cern.ch DESCRIPTION:Speakers: Vladimir Kopeliovich (Institute for nuclear research of RAS)\nThe angular dependence of the cumulative particles production of f nuclei near the kinematical boundary for multistep process is defined by characteristic polynomials in angular variables\, describing spatial mome nta of the particles in intermediate states [1\, 2]. Physical argumentatio n\, exploring the small phase space method\, leads to the appearance of eq uations for these polynomials in $cos (\\theta/N)$\, where $\\theta$ is th e polar angle defining the momentum of final (cumulative) particle\, \nthe integer $N$ being the multiplicity of the process (the number of interact ions).\nIt is shown explicitly how these equations aappear\, the recurrent relations between polynomials with different $N$ are obtained. Factorizat ion properties of characteristic polynomials found in our previous work [3 ] are extended\, and their connection with known in mathematics Chebyshev polynomials of 2-d kind [4\, 5] is established. \nAs a result\, differenti al cross section of the cumulative particle production has characteristic behaviour $d\\sigma \\sim 1/ \\sqrt {\\pi - \\theta}$ near the strictly ba ckward direction ($\\theta = \\pi$\, the backward focusing effect). Such b ehaviour takes place for any multiplicity of the interaction\, beginning w ith $n=3$\, elastic or inelastic (with resonance excitations in intermedia te states) and can be called \nthe nuclear glory phenomenon\, or 'Buddha's light' of cumulative particles.\n\n1. V.B. Kopeliovich. Sov.J.Nucl.Phys. 26 (1977) 87 [Yad.Fiz. 26 (1977) 168] \n\n2. V.B. Kopeliovich. Phys. Rep t. 139 (1986) 51\n\n3. V.B.Kopeliovich\, G.K.Matushko and I.K.Potashnikov a J.Phys. G41 (2014) 125107\; \nVladimir Kopeliovich and Galina Matushko. 'Buddha's light' of cumulative particles. Nuclear Glory Phenomenon. Schola rs Press\, Saarbruecken\, Germany. 2015. \nISBN 978-3-639-76496-3. \n\n4. Chebyshev polynomials. https://en.wikipedia.org/wiki/Chebyshevpolynomials\ n5. Mnogochleny Chebysheva. https://ru.wikipedia.org/wiki/Mnogochleny-Cheb ysheva\n\nhttps://indico.particle.mephi.ru/event/4/contributions/749/ LOCATION:Milan Hotel Verdi URL:https://indico.particle.mephi.ru/event/4/contributions/749/ END:VEVENT BEGIN:VEVENT SUMMARY:Analysis of some modes of multibody decays of low excited actinide nuclei. DTSTART;VALUE=DATE-TIME:20161014T115500Z DTEND;VALUE=DATE-TIME:20161014T121500Z DTSTAMP;VALUE=DATE-TIME:20260814T163101Z UID:indico-contribution-108-748@cern.ch DESCRIPTION:Speakers: Yuri Pyatkov (MEPhI)\nIn our previous pablications d evoted to the collinear cluster tri-parttition (CCT) of the low excited nu clei [1-3] we have paid attention to specific linear structures in two-dim ensional mass distributions of fission fragments (FFs). Just such structur es always linked with magic clusters and located in the region of an essen tial missing mass are treated as the manifestations of multibody decay. A lot of different CCT modes (structures) were observed so far [3]. Physical scenario standing behind each mode is a subject of much current interest. We present the results of analysis of the most pronounced CCT modes. Very nontrivial prescission configurations likely give rise to some of the mod es observed. \nReferences\n1. Yu. V. Pyatkov et al.\, Eur. Phys. J. A 4 5 (2010) 29\n2. Yu. V. Pyatkov et al.\, Eur. Phys. J. A 48 (2012) 94\n3 . D.V. Kamanin\, Yu. V. Pyatkov\, "Clusters in Nuclei - Vol.3" ed. by C. Beck\,\n Lecture Notes in Physics 875\, pp. 183-246 (2013)\n\n https://indico.particle.mephi.ru/event/4/contributions/748/ LOCATION:Milan Hotel Verdi URL:https://indico.particle.mephi.ru/event/4/contributions/748/ END:VEVENT BEGIN:VEVENT SUMMARY:Charged particle formation in the reaction of stopped pion absorpt ion by light nuclei DTSTART;VALUE=DATE-TIME:20161014T103500Z DTEND;VALUE=DATE-TIME:20161014T105500Z DTSTAMP;VALUE=DATE-TIME:20260814T163101Z UID:indico-contribution-108-669@cern.ch DESCRIPTION:Speakers: Roman Pritula (MEPhI)\nThe results of the investigat ion on spectra and yields of hydrogenium and helium isotopes formed in the reaction of the stopped pion absorption by atomic nuclei are presented. T he study is based on the unique data on charged particle formation followi ng pion absorption on 17 target nuclei in the mass range 6 \n\nhttps://ind ico.particle.mephi.ru/event/4/contributions/669/ LOCATION:Milan Hotel Verdi URL:https://indico.particle.mephi.ru/event/4/contributions/669/ END:VEVENT BEGIN:VEVENT SUMMARY:TEST OF NUCLEAR FRAGMENTATION MODELS WITH CARBON FRAGMENTATION AT 0.3 GeV/n DTSTART;VALUE=DATE-TIME:20161014T111500Z DTEND;VALUE=DATE-TIME:20161014T113500Z DTSTAMP;VALUE=DATE-TIME:20260814T163101Z UID:indico-contribution-108-622@cern.ch DESCRIPTION:Speakers: Viacheslav Kulikov (SSC RF ITEP of NRC Kurchatov In stitute)\nCarbon fragmentation at 0.3 GeV per nucleon on Be\, Al\, Cu and Ta targets has been studied in the FRAGM experiment at ITEP TWA heavy ion accelerator. Momentum spectra of all long lived nuclear fragments from hyd rogen isotopes to isotopes of the projectile carbon nuclei were measured with the beamline spectrometer placed at an angle of 3.5 degrees to the be am direction. The fragment momentum spectra span the regions of the fragme ntation peaks as well as the cumulative region. The differential cross sec tions cover up to five orders of magnitude. The obtained data were used f or high precision test of a target independence of fragmentation processes in fragmentation peak regions predicted by statistical models. The data w ere also compared with predictions of few Monte Carlo models of ion-ion in teractions: Binary Cascade\, INCL++\, LAQGSM and QMD. Successes and drawba cks of above mentioned models are discussed.\n\nhttps://indico.particle.me phi.ru/event/4/contributions/622/ LOCATION:Milan Hotel Verdi URL:https://indico.particle.mephi.ru/event/4/contributions/622/ END:VEVENT BEGIN:VEVENT SUMMARY:Formation of $\\\,^{3\,4}$He in the reaction of stopped pions abso rption DTSTART;VALUE=DATE-TIME:20161014T105500Z DTEND;VALUE=DATE-TIME:20161014T111500Z DTSTAMP;VALUE=DATE-TIME:20260814T163101Z UID:indico-contribution-108-568@cern.ch DESCRIPTION:Speakers: Tatiana Leonova (NRNU MEPhI)\nThe results of the inv estigation on spectra and yields of helium isotopes $\\\,^{3\,4}$He formed in the reaction of stopped pion absorption by atomic nuclei are presented .. The work is based on the unique set of data on the charged particles fo rmation on the seventeen target nuclei in the range of mass numbers $6 30$ MeV. Analysis of other secondary processes which can lead to the formatio n of slow $\\\,^{3\,4}$He has been made.\n\nThe reported study was funded by RFBR according to the research project No. 16-32-00734\n\nhttps://indic o.particle.mephi.ru/event/4/contributions/568/ LOCATION:Milan Hotel Verdi URL:https://indico.particle.mephi.ru/event/4/contributions/568/ END:VEVENT BEGIN:VEVENT SUMMARY:STUDY OF n-n CORRELATIONS IN d+2H→p+p+n+n REACTION DTSTART;VALUE=DATE-TIME:20161014T113500Z DTEND;VALUE=DATE-TIME:20161014T115500Z DTSTAMP;VALUE=DATE-TIME:20260814T163101Z UID:indico-contribution-108-500@cern.ch DESCRIPTION:Speakers: Evgeny Konobeevski (Institute for Nuclear research)\ nThe goal of this work is an experimental study of neutron-neutron interac tion and\, in particular\, of mechanisms of *nn*-correlations in few-nucle on systems. According to [1] strong discrepancies of experimental data and theory observed in nd- and pd-breakup reactions [2\, 3] can be explained by a significant strengthening of nn- and pp-correlations of attractive ch aracter in the third nucleon field in 3H (pnn) and 3He (ppn) systems.\n\nI n this work the *d* + 2H → *p + p + n +n* reaction is studied at 15 MeV deuteron beam of U-120 cyclotron of Skobel’tsyn Institute of Nuclear Phy sics\, Moscow State University. In this reaction\, the correlated nn- and pp- singlet pairs can be formed dynamically in the intermediate state. Thu s\, the measured nn- and pp-correlations\, in particular\, energies of *nn * (*pp*) singlet quasi-bound states can appear different than those inhere nt for a free nn- and pp-systems.\n\nFor the first time\, in a kinematical ly complete experiment the energy of quasi-bound state of 2n-system is det ermined. The energy of the nn 1S0 state is determined by comparing experim ental time-of-flight spectrum of the neutron from the breakup of 2n-system with simulation spectra depending on this energy. The obtained value Enn = 76 $\\pm$ 6 keV is significantly lower than energies (120 – 160 keV) r ecalculated from the experimental values of 1S0 nn-scattering length [3-5] \, that perhaps indicates an effective enhancement of nn-interaction in th e intermediate state of studied reaction. This work was partly supported b y RFBR under grant N16-32-00743.\n\n1. Konobeevski E.S.\, Kukulin V.I.\ , Zuyev S.V. et al. Bull. Russ. Acad. Sci. 78\, 341 (2014).\n2. Witala H. and Glöckle W. Phys. Rev. C 83\, 034004 (2011).\n3. Ruan X.S. et al . Phys. Rev. C 75\, 057001 (2007).\n4. Huhn V. et al. Phys. Rev. C 63\ , 014003 (2000).\n5. Gonzales Trotter D. E. et al. Phys. Rev. C 73\, 03 4001 (2006).\n\nhttps://indico.particle.mephi.ru/event/4/contributions/500 / LOCATION:Milan Hotel Verdi URL:https://indico.particle.mephi.ru/event/4/contributions/500/ END:VEVENT END:VCALENDAR