BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Yields of the r-process in neutron star merger ejecta and its sens itivity to nuclear mass model choice DTSTART;VALUE=DATE-TIME:20220713T153000Z DTEND;VALUE=DATE-TIME:20220713T155000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-651@events.sinp.msu.ru DESCRIPTION:Speakers: Vasily Negrebetskiy ()\nThe astrophysical r-process of nucleosynthesis is widely considered to explain the production of major amount of nuclei beyond the iron peak. This nucleosynthesis mechanism pos es great interest to both astrophysics and nuclear physics. Taking place a t temperatures above 1 GK and very high densities\, it is believed to occu r in extreme astrophysical scenarios\, such as neutron star mergers and su pernova blasts. Thus the main approach in r-process study is computer simu lation.\n\nNuclei that take part in r-process reaction chains are exotic d ue to high neutron excess. To get their characteristics required by nucleo synthesis simulations theoretical nuclear models are used. We study the im pact of the nuclear mass model choice on the results of r-process calculat ion. Using three different theoretical mass tables [1\,2\,3] we have creat ed three libraries of astrophysical nuclear reactions based on REACLIB [4] database. We used them to simulate r-process in neutron star merger dynam ical ejecta with the help of the SkyNet [5] library. Obtained results show how our r-process simulation responds to the mass model variation.\n\nFig . 1. Theoretical r-process yields\, calculated with different nuclear mas s models\, compared to experimental nuclei abundances in the Solar System. \n\n\n1. P. Möller et al\, ADNDT 109\, 1 (2016).\n2. S. Goriely\, N. Cha mel\, J.M. Pearson\, Phys. Rev. C 88\, 024308 (2013).\n3. Е.В. Влад имирова и др.\, Изв. РАН. Серия Физическая 4\, 571 (2022).\n4. R.H. Cyburt et al\, ApJ 189\, 240 (2010).\n5. J. Lippu ner\, L.F. Roberts\, ApJS 233\, 18 (2017).\n\nhttps://events.sinp.msu.ru/e vent/8/contributions/651/ LOCATION: Физический ф-т\, 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/651/ END:VEVENT BEGIN:VEVENT SUMMARY:Variants of intensive antineutrino sources on the base of 8Li isot ope DTSTART;VALUE=DATE-TIME:20220714T153000Z DTEND;VALUE=DATE-TIME:20220714T155000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-471@events.sinp.msu.ru DESCRIPTION:Speakers: Vladimir Lyashuk (Institute for Nuclear Research (IN R) of the Russian Academy of Sciences)\nThe winning properties combination of the β--decayed 8Li isotope (short $T {_{1/2}}$= 0.84 s\, hard and kno wn antineutrino spectrum (with maximum at ~13 MeV and average energy = 6.5 MeV) and availability of lithium are the undoubted base to consider 8Li as the very perspective isotope for construction of the antineutrino sourc e as the powerful instrument for different neutrino experiments. In spite of the high antineutrino flux from nuclear reactors the spectrum are chara cterized with significant errors ((4-6)% -precision at energy up to ~6 MeV ) caused by unknown schemes of decays\, time variations\, presence of the spent nuclear fuel\, that put together cause an unsolved puzzles in preci sion and interpretation of neutrino oscillation results [1].\n The const ruction of the intensive antineutrino source is possible in different sche mes basing as on the nuclear reactor (as neutron source for (n\,γ)-activa tion of purified 7Li) as on the tandem scheme of the accelerator with neut ron producing target plus lithium blanket (neutron converter) irradiated b y $^{7}{\\rm Li}(n\,\\gamma)^{8} {\\rm Li}$ activation [2]. In the source realized in transport regime (first variant) an activated 7Li is pumped in the close cycle through the active zone of the reactor\; further (in сyc le) it is delivered close to the neutrino detector. The scheme really allo ws to decrease the total spectrum errors in order of values [3]. Another f eature of this concept is high count rate ensured in the compact (about cu bic meter) neutrino detector – ~10e+4 $(\\bar \\nu{_e} \, p)$-events ($m ^{-3}$$day^{-1}$GW$^{-1}$) [4]. \n In the other perspective realization t he proton beam strike into the heavy-element-target and produces the signi ficant neutron yield for the lithium blanket irradiation. The scheme is co nsidered for energies up to ~600 MeV for different heavy targets (W\, Pb\, Vi\, Ta). The density of 8Li creation is simulated in details that allowe d to propose an effective blanket scheme with central lithium containing v olume enclosed by carbon (acting as an effective neutron reflector) and ou ter thick water layer for diminish the neutron escape. The analysis of 8Li distribution in the blanket allows to propose an alternative approach of tandem schemes based on developed compact accelerators with proton energy about several tens of MeV that opens another important possibility - to co nstruct a small-volume-antineutrino-source (of short dimension ~70 cm) tha t is exclusively important for search of sterile neutrinos in case of $\\D elta m^2 \\ge 1\\: {\\text{эВ}}^2$ [ 5].\n\n1. C. Giunti\, Y.F. Li\, C .A. Ternes\, and Z. Xin. arXiv:2110.06820 (2022).\n2. V.I. Lyashuk & Yu.S. Lutostansky. Bull. Russ. Acad. Sci. Phys. 79\, 431–436 (2015). [https: //doi.org/10.3103/S106287381504022X][1]\n3. V.I. Lyashuk. Results Phys. 7\ , 1212 (2017). [https://doi.org/10.1016/j.rinp.2017.03.025][2].\n4. V.I. L yashuk. JHEP06 (2019)135. [DOI: 10.1007/JHEP06(2019)135][3]\n5. J. Kopp\, M. Maltoni and T. Schwetz\, Phys. Rev. Lett. 107\, 091801 (2011). DOI:[htt ps://doi.org/10.1103/PhysRevLett.107.091801][4]\n\n\n [1]: https://doi.or g/10.3103/S106287381504022X\n [2]: https://doi.org/10.1016/j.rinp.2017.03 .025\n [3]: https://doi.org/10.1007/JHEP06(2019)135\n [4]: https://doi.o rg/10.1103/PhysRevLett.107.091801\n\nhttps://events.sinp.msu.ru/event/8/co ntributions/471/ LOCATION: Физический ф-т\, ауд. 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/471/ END:VEVENT BEGIN:VEVENT SUMMARY:Search of periodical and aperiodical variations of nucleus decay parameters DTSTART;VALUE=DATE-TIME:20220714T151000Z DTEND;VALUE=DATE-TIME:20220714T153000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-460@events.sinp.msu.ru DESCRIPTION:Speakers: Sergey Mayburov (Lebedev Institute of Physics)\nPoss ible temporal variations of nucleus decay parameters were studied extensi vely in the last years\, their observation can be the signal of unknown physical effects. Several experiments reported the annual and daily decay rate oscillations in alpha and beta-decays of some radioactive nuclides at the level of .05 % [1\,2]. Also\, correlation of Mn-54 e-capture deca y rate with electromagnetic solar activity was reported [1]. BSTU - PhIAN collaboration studies decay rate variations in inverse beta-decay (e-cap ture) of Fe-55 isotope. In this process K-shell electron absorbed by nucl ei and electron neutrino emitted\; it accompanied by X-ray with energy 5\, 9 or 6\,4 KeV which in our set-up detected by cooled Si-Pin detectors. Mea surements of decay rate performed in 2016 -2021 \, demonstrate that togeth er with observed Fe-55 decay exponent with life-time 1004 days\, oscillat ion period 29.5 +/- 1.5 days corresponding to moon month is found with am plitude (.22 +/- .04)% \; \npossible model of such decay rate deviations considered in [3\,4].\n Possible influence of electromagnetic so lar activity was studied during 2015 – 2020 for Fe-55 decay rate\, simul taneously with Co-60 beta-decay rate measured by germanium detector in Nov osibirsk INF at the distance 2800 km from Moscow [5]. The deviations of s imilar form and size from exponential decay low at the average level (.5 5 +/-.004)% were detected in both experiments during October- December 201 8. Supposedly\, they can be related to solar activity minimum started in the beginning of 2019. In addition\, six decay rate dips of the order 1 % of decay rate and with duration from 40 to 208 hours were found. It is sh own that their occurrence correlate with x-ray solar flare events with sig nificant reliability\, existence of such correlation can have important pr actical applications [4]. SOLARIS project of our collaboration plans to pe rform simultaneous measurements of Fe-55\, Co-60 decay parameters on Inter national Space Station and Earth lab. \n to study their correlations with X-ray solar activity.\n\n\n 1. E. Fischbach et al. \, Rev. Space Sci . 145\, 285 (2009)\; Astrop. Phys. 59\,47 (2014)\n\n 2. E. Alekseev e t al. \, Phys. Part. Nucl. 47\, 1803 (2016)\; ibid. 49\, 557 (2018) \n\n 3. S. Mayburov Int. J. Theor. Phys. 60\, 630 (2021) \n\n 4. S. May burov Phys. Part. Nucl. 51\, 458 (2020)\n \n 5. S. Bogachev et al . J. Phys.: Conf. Series 1690\, 012028-012035 (2020)\n\nhttps://events.s inp.msu.ru/event/8/contributions/460/ LOCATION: Физический ф-т\, ауд. 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/460/ END:VEVENT BEGIN:VEVENT SUMMARY:NEW RESULTS FOR DOUBLE BETA DECAY OF 106Cd DTSTART;VALUE=DATE-TIME:20220714T145000Z DTEND;VALUE=DATE-TIME:20220714T151000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-341@events.sinp.msu.ru DESCRIPTION:Speakers: NIKOLAY RUKHADZE (JINR)\nSearch for β+β+\, β+EC\, EC/EC decay of 106Cd was performed at the Modane underground laboratory ( LSM\, France\, 4800 m w.e.) using the low-background multi-detector spectr ometer TGV-2 [1] and 106Cd with enrichment of 99.57%. The detector part of the spectrometer is composed of 32 HPGe planar type detectors each with s ensitive volume of 20.4 cm2  0.6 cm. 16 foils of 106Cd with a thickness of 70(10) μm\, and a total mass of ~23.2 g (~1.3 × 1023 atoms of 106Cd) were inserted between the entrance windows of detectors. The distance fro m foils to detectors is about 1.5 mm. The 16 pairs of detectors with cadmi um foils were mounted one over another in a common cryostat tower. The ene rgy resolution of detectors are ranged from 3.0 to 4.0 keV at 1332 keV γ- line of 60Co. The design of the detector part of TGV-2 delivers high detec tion efficiency for useful events (single and multiple coincidence) and st rong suppression of external background. The passive shielding of the TGV- 2 consist of copper (20 cm)\,\, an airtight box against radon\, lead ( 10 cm) and a neutron shielding made of borated polyethylene (16 cm). Ad ditional suppression of background was achieved by using coincidence techn iques and filtering electronic and microphone noise in the low energy regi on (<50 keV) by digitizing the detector response with different shaping ti mes (2 and 8 μs) [1]. Double coincidences between two characteristic KX- rays of Pd detected in neighboring detectors were analyzed to search for 2 νEC/EC decay of 106Cd to the ground 0+ state of 106Pd. From the prelimina ry calculation of experimental data accumulated with TGV-2 spectrometer an d ~23.2 g of 106Cd during 43000 h (phase III of experiment TGV-2)\, new li mit on 2νEC/EC decay of 106Cd to the ground 0+ state of 106Pd - T1/2 > 1. 7 × 1021y (90% C.L) was obtained. Limits on 2νECEC decay of 106Cd to exc ited states of 106Pd and 2νβ+β+\, 2νβ+EC decay of 106Cd to the ground 0+\, and excited states of 106Pd were significantly improved in compariso n with previous phase II of the TGV-2 experiment [2]. They are ranged from 5.0 × 1020 y to 1.2 × 1021 y at 90% C.L. \n\n 1. P. Beneš et al.\ ,Nucl. Instr. Meth. in Phys. Res. A 569\, 737 (2006)\n 2. N. I. Rukha dze et al.\, J. Phys.: Conf. Ser. 375\, 042020 (2012)\n\nhttps://events.si np.msu.ru/event/8/contributions/341/ LOCATION: Физический ф-т\, ауд. 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/341/ END:VEVENT BEGIN:VEVENT SUMMARY:Distribution on electron energy in two-neutrino double beta deca y of 100Mo DTSTART;VALUE=DATE-TIME:20220714T143000Z DTEND;VALUE=DATE-TIME:20220714T145000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-483@events.sinp.msu.ru DESCRIPTION:Speakers: Sergei Semenov (National Research Centre "Kurchatov Institute")\nNowadays a considerable attention is paid to experiments on t wo-neutrino double beta decay of stable isotopes. In large-scale projects a great amount of data on 22-transitions is accumulated\, which give s the possibility to build the intensity distribution on total emitted el ectrons energy.. These information can be used in searching for new physic s\, for example\, aimed at investigation of neutrino statistics [1]\, Lore ntz violation effects [2]\, two-neutrino double beta-decay with sterile ne utrinos [3].\n In measurements\, produced with the help of NEMO-3 detect or\, which is capable to reconstruct the full topology of  processes \, characteristics of more than 600 000 22-decays of 100Mo have bee n recorded [4]. \n In order to provide a way for new physics searches it i s necessary to determine the nuclear mechanism of 22-transition. In the same way as for the ordinary -decay\, it is reasonale to consruct K urie plot for double beta-process [3]. Kurie plot has different form for two kinds of 22-amplitude : when contribution of lowest 1+ -energy level of intermediate nucleus dominates - single state dominance\, SSD\, and for the case of higher-states dominance\, HSD. Kurie plots for 100Mo t wo-neutrino double beta-decay were built for SSD mechanism with a certain addition to amplitude of low-lying excited 1+ - states of intermediate nuc leus 100Tc [5]\, for HSD mechanism\, and for double beta--decay with emiss ion of sterile neutrino\, corersponding to both SSD and HSD nuclear mechan isms.\n\n\n\n1. A.S. Barabash\, A.D. Dolgov\, R. Dvornicky\, F. Šimkovic\ , A.Yu. Smirnov\, Nucl. Phys. 783\, 90 (2007) \n2. O. Nitescu et al\, J. P hys. G 47\, 55112 (2021)\n3. P.B. Bolton\, F.F. Deppisch\, L.Graf\, F Ši mkovic Phys. Rev. D 103\, 055019 (2021)\n4. R. Arnold et al\, (NEMO-3 Co llaboration) Eur. J. Phys. C 79\, 440 (2019)\n5. S.V. Semenov\, Phys. Part . Nucl. 48\, 1018 (2017) \;\n S.V. Semenov. Phys. Part. Nucl.\, 49 \, 698 (2018)\n\nhttps://events.sinp.msu.ru/event/8/contributions/483/ LOCATION: Физический ф-т\, ауд. 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/483/ END:VEVENT BEGIN:VEVENT SUMMARY:IMPLEMENTATION OF GLOBAL BETA-DECAY RATES PREDICTIONS TO ASTROPHYS ICAL MODELS DTSTART;VALUE=DATE-TIME:20220714T141000Z DTEND;VALUE=DATE-TIME:20220714T143000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-439@events.sinp.msu.ru DESCRIPTION:Speakers: Igor Panov (National Research Center “Kurchatov in stitute”)\nIn nucleosynthesis of heavy nuclei\, following neutron star m erger (NSM) [1]\, short-lived not experimentally researched nuclei are inv olved. That is why for their formation modelling the global predictions o f different nuclear parameters are needed. The beta-decay rate is one of t he main important parameter of such short lived nuclei. Heavy nuclei abun dance calculation\, taking into account different nuclear parameters predi ctions\, is in fact theoretical integral experiment\, in which the opportu nities of theoretical models can be compared on the basis of observations and calculations of heavy elements abundances.\nStrong dependence of eleme nt abundances\, produced in NSM scenario on beta-decay rates model [2] hav e shown strong difference in the abundances with different beta-decay ra tes predictions used. In present work we considered the role of beta-decay rates predictions in scenario of low neutron mass explosion\, emerged at the end of close binary evolution of two neutron stars with different mass es [3]. Different beta-decay rates predictions\, such as random phase appr oximation (qRPA) [4]\, proton-neutron relativistic quasiparticle phase app roximation (pn-RQRPA) [5] and finite amplitude method (pnFAM) [5]\, were a pplied to the same nucleosynthesis model [6]\, used earlier for NSM [2]. \ nIt was shown that different global beta-decay rates predictions [4-6]\, a pplied to nucleosynthesis calculations\, leads to formation of realistic s tructure of the abundance curve of chemical elements during weak r-process . And contrary to nucleosynthesis in NSM-scenario\, the formation of heav y elements in the region between first and second peaks weakly depend on b eta-decay model. \nThe work was done under financial support of Russian Na tional Fond (project №. 21-12-00061).\n\n1. J. Cowan\, C. Sneden\, J. E. Lawler\, et al. // Rev. Mod. Phys. 93. id. 015002. (2021).\n2. I.V. Panov // Book of Abstracts. Int. Conf. “NUCLEUS – 2021”. Ed. Kovalenko. P .269.\n3. S. I. Blinnikov\, D. K. Nadyozhin\, N. I. Kramarev\, A. V. Yudin // Astronomy Reports. 65. 385. (2021).\n4. P. Mo¨ller\, J.R. Nix\, and K .-L. Kratz // ADNDT. 66. 131. (1997).\n5. T. Marketin\, L. Huther\, G. Mart´ınez-Pinedo // Phys. Rev. C. 93. Id. 025805. (2016).\n6. E. M. Ne y\, J. Engel\, N. Schunck // Phys. Rev. C. 102. Id. 034326. (2020).\n7. I. V. Panov\, A. V. Yudin // Astronomy Letters. 46. 518. (2020).\n\nhttps:/ /events.sinp.msu.ru/event/8/contributions/439/ LOCATION: Физический ф-т\, ауд. 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/439/ END:VEVENT BEGIN:VEVENT SUMMARY:MEASUREMENT OF RADON DECAYS WITH THE LVD-SETUP FOR NEUTRINO SEARCH ING DTSTART;VALUE=DATE-TIME:20220714T130000Z DTEND;VALUE=DATE-TIME:20220714T132000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-461@events.sinp.msu.ru DESCRIPTION:Speakers: Natalia Agafonova (Institute for Nuclear Research o f RAS)\nThe Large Volume Detector (LVD)\, located at the Gran Sasso Low Ba ckground Laboratory in Italy\, is built to search for neutrinos from stell ar core collapses in our galaxy. [1\, 2]. \nThe peculiarity of the search for rare events requires close attention to the background of the experime nt\, such as the natural radioactivity of the rock and detector materials [3] and particles of the interaction of cosmic ray muons underground [4]. \nThe LVD detector measures gamma quanta from the decay of radon daughter nuclei.\nRadon is the main source of the variable background component in the underground hall\, whose concentration variations are composed of seve ral components. Long-term\, seasonal variations are associated with change s in rock moisture [5]. The daily variations of radon are affected by air mixing due to the opening of the gates in the hall [6]. We convincingly sh ow the connection between the change in the concentration of radon nuclei in the experimental hall and the change in the count rate of background pu lses from gamma rays in the detector.\nWe also point out the existence of another source of radon change\, this is seismic activity. An increase in radon emanation a few days before an earthquake poses the problem of the p ossibility of predicting seismic events. We present some typical LVD time series patterns during major earthquakes in Italy in recent years.\n\n1. G . Bari\, M. Bazile\, G. Bruni et al. Nucl. Instrum. Meth. Phys. Res. A. 26 4\, 5 (1988).\n2. N. Y. Agafonova et al. (LVD Collaboration). Astrophys. J our. 802\, 47 (2015)\n3. C. Bucci et al. Eur. Phys. J. A 41\, 155 (2009).\ n4. R. Persiani\, PhD Thesis\, Bologna: Univ. Bologna\, (2011).\n5. N.Yu. Agafonova et al. Bulletin of the Russian Academy of Sciences: Physics. 83\ , 614 (2019).\n6. N.Yu. Agafonova\, V.A. Alekseev\, E.A. Dobrynina\, et al .\, Preprint of the Inst. Nucl. Res.\, Russ. Acad. Sci.\, Moscow\, no. 107 1/2001 (2001).\n\nhttps://events.sinp.msu.ru/event/8/contributions/461/ LOCATION: Физический ф-т\, 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/461/ END:VEVENT BEGIN:VEVENT SUMMARY:(α\,n) and (α\,nγ) yield calculations with a new version of Neu CBOT for low background experiments DTSTART;VALUE=DATE-TIME:20220714T124000Z DTEND;VALUE=DATE-TIME:20220714T130000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-416@events.sinp.msu.ru DESCRIPTION:Speakers: Maxim Gromov (SINP MSU\, JINR)\nUranium and thorium are distributed in all natural materials surrounding us and\, in particula rly\, in the construction materials of low background detectors. Therefore \, the (α\,n) and (α\,nγ) reactions which occur as a result of α-decay s of U\, Th and their daughters generate intrinsic neutron and gamma backg rounds for the modern ultra-pure neutrino and dark matter detectors. To co nstruct a low background experimental setup\, selection of materials shoul d be done on the basis of assays of the radionuclide relative concentratio ns and calculations of neutrons and gamma yields. The NeuCBOT program (Neu tron Calculator Based On TALYS) can be used for the computation part. We p resent an updated version with new functionality namely use of partial cro ss sections for excited states of the daughter nucleus and calculation of the (α\,nγ) reactions and the respective yields in addition to evaluatio n of the neutron yields in the (α\,n) reactions. Also\, a selection of di fferent databases (TENDL\, JENDL) and a graphical interface were added to the program. We repeated validation comparisons with other (α\,n) data co ming from measurements and calculations. A list of results of the neutron and gamma background estimations for many materials commonly used in low b ackground detector was prepared. Among others the list includes plastics d oped by gadolinium\, structural plastics and construction titanium of vari ous grades.\n\nhttps://events.sinp.msu.ru/event/8/contributions/416/ LOCATION: Физический ф-т\, 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/416/ END:VEVENT BEGIN:VEVENT SUMMARY:SIMULATION OF THE LSD RESPONSE TO THE NEUTRINO BURST FROM SN 1987A DTSTART;VALUE=DATE-TIME:20220714T122000Z DTEND;VALUE=DATE-TIME:20220714T124000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-329@events.sinp.msu.ru DESCRIPTION:Speakers: Andrey Yudin (NIC "Kurchatov Institute")\nUsing the Geant4 code\, we have performed [1] a thorough simulation of the LSD detec tor response to the neutrino burst from SN 1987A. The neutrino flux parame ters were chosen according to one of the models: the standard collapse mod el or the rotational supernova explosion model [2]. We showed that\, depen ding on the chosen parameters\, one can either obtain the required number of pulses in the detector or reproduce their energy spectrum\, but not bot h together. The interaction of neutrino radiation both with LSD itself and with the material of the surrounding soil was taken into account in our s imulation. We also explored the hypothesis [3] that the entire unique LSD signal at 2:52 UT was produced by neutron fluxes from the surrounding gran ite. However\, this hypothesis was not confirmed by our simulation.\n\nhtt ps://events.sinp.msu.ru/event/8/contributions/329/ LOCATION: Физический ф-т\, 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/329/ END:VEVENT BEGIN:VEVENT SUMMARY:Recent results of the KamLAND-Zen experiment DTSTART;VALUE=DATE-TIME:20220714T120000Z DTEND;VALUE=DATE-TIME:20220714T122000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-511@events.sinp.msu.ru DESCRIPTION:Speakers: Alexandre Kozlov (MEPhI)\nThe KamLAND-Zen experiment provided new stringent constraints on the neutrinoless double-beta (0νβ β) decay half-life in Xe-136 using a xenon-loaded liquid scintillator. I mproved search was based on an upgraded detector with almost double the am ount of enriched xenon and an ultra-low radioactivity container\, correspo nding to an exposure of 970 kg yr of Xe-136. This new data provides valuab le insight into backgrounds\, especially from cosmic muon spallation of xe non\, and has required the use of novel background rejection techniques. W e obtained a lower limit for the 0νββ decay half-life of T1/2 > 2.3 × 10^26 yr at 90% C.L.\, corresponding to upper limits on the effective Majo rana neutrino mass of 36 – 156 meV using commonly adopted nuclear matrix element calculations.\n\nhttps://events.sinp.msu.ru/event/8/contributions /511/ LOCATION: Физический ф-т\, 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/511/ END:VEVENT BEGIN:VEVENT SUMMARY:Finite nuclei size effects in elasticity of neutron star inner cru st DTSTART;VALUE=DATE-TIME:20220713T151000Z DTEND;VALUE=DATE-TIME:20220713T153000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-547@events.sinp.msu.ru DESCRIPTION:Speakers: Andrey Chugunov (Ioffe Institute)\nWhen considering elasticity in terrestrial conditions\, one can safely neglect the nuclear size and treat nuclei as point charges\, which create the electrostatic po tential for electrons. However\, it is not the case for the deepest layers of neutron star inner crust\, where the distance between nuclei becomes o f the same order as their sizes (e.g. [1\,2]). In these conditions\, the e lectrostatic potential\, induced by nearby nuclei and electrons\, can affe ct nuclei shape and indeed\, the most energetically favorable shape of nuc lei can substantially differ from spherical one (so-called pasta-phases in the mantle region) [1\,2]. Here we analyze the elasticity of the matter u nder these conditions. In comparison with [3]\, we consider not only the m antle region but also spherical nuclei of the deepest layers of the inner crust. We also take into account neutron skin as well as the fact that nuc leon number density can be affected by deformation. The latter effect decr eases elastic energy.\n\n1. N. Chamel\, P. Haensel\, Living Rev. Relativ. 11\, 10 (2008).\n2. C. J. Pethick\, D. G. Ravenhall\, Annu. Rev. Nucl. Par t. Sci. 45\, 429 (1995).\n3. C. J. Pethick and A. Y. Potekhin\, Physics Le tters B 427\, 7 (1998).\n\nhttps://events.sinp.msu.ru/event/8/contribution s/547/ LOCATION: Физический ф-т\, 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/547/ END:VEVENT BEGIN:VEVENT SUMMARY:On the stability of spherical nuclei in the inner crust of neutron stars DTSTART;VALUE=DATE-TIME:20220713T145000Z DTEND;VALUE=DATE-TIME:20220713T151000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-422@events.sinp.msu.ru DESCRIPTION:Speakers: Nikita Zemlyakov ()\nThe inner crust of neutron star s contains nuclei with large neutron excess. Furthermore\, in the deepest layers they can take a substantially non-spherical shape (this region is t ypically referred to as mantle) [1]. The stability of spherical nuclei in inner crust with respect to fission was considered in [2]. The authors app ly the fission instability criterion for spherical nuclei\, derived by Boh r and Wheeler for terrestrial conditions [3]. It was predicted that spheri cal nuclei should lose stability when the ratio of nucleus volume to Wigne r-Seitz cell volume (filling factor) reaches a value of 0.125 [2]\, as a r esult authors suggest that this instability can be a mechanism of transiti on to the mantle. However\, according to our calculations within compressi ble liquid drop model\, the spherical nuclei remain energetically favorabl e for filling factors up to 0.2 [4]. Obviously\, this contradiction have t wo possible solutions: A) complex nuclear structures (e.g.\, [5])\, which stays beyond scope of [4]\, correspond to the true thermodynamic equilibri um for filling factors 0.125-0.2\; B) the fission instability is suppresse d in the inner crust\, as it was argued qualitatively in [6]. Here we demo nstrate that the proposition B) holds true. Similar result was obtained in [7]\, but\, as we argue here\, it was based on incorrect conditions at Wi gner-Seitz cell boundary. \nIn inner crust of a neutron star\, the nuclei are immersed into degenerate electrons\, which provides background charge density of the same order of magnitude as charge density inside the nucleu s. This background creates an electrostatic potential\, which supports sph erical shape of the nuclei. As a result\, spherical nuclei becomes stable with respect to quadrupole deformations for all values of the filling fact or\, if their number density correspond to the optimal value. However\, if the number of atomic nuclei per unit volume is much lower than the equili brium value\, instability may arise and leading to nuclear fission and inc rease of nuclei number density. This phenomenon may be important in the fo rmation of the crust in the early evolutionary stages of neutron stars.\nW ork is supported by Russian Science Foundation (Grant No. 19-12-00133).\n\ n1. N. Chamel N.\, P. Haensel\, Living Rev. Relativ. 11\, 10 (2008).\n2. C hristopher J. Pethick\, David G. Ravenhall\, Annu. Rev. Nucl. Part. Sci. 4 5\, 429 (1995).\n3. N. Bohr\, John A. Wheeler\, Phys. Rev. 56\, 426 (1939) .\n4. Nikita A. Zemlyakov\, Andrey I. Chugunov\, Nikolay. N. Shchechilin\, J. Phys. Conf. Ser. 2103\, 012004 (2021).\n5. William G. Newton\, Sarah C antu\, Shuxi Wang\, Amber Stinson\, Mark Alexander Kaltenborn\, Jirina Rik ovska Stone\, Phys. Rev. C 105\, 025806 (2022).\n6. G. Watanabe\, Progress of Theoretical Physics Supplement 186\, 45 (2010).\n7. S. Kubis\, W. Wojc ik\, arXiv:2102.06675 (2021).\n\nhttps://events.sinp.msu.ru/event/8/contri butions/422/ LOCATION: Физический ф-т\, 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/422/ END:VEVENT BEGIN:VEVENT SUMMARY:Neutron star properties with density dependent baryonic interactio ns DTSTART;VALUE=DATE-TIME:20220713T143000Z DTEND;VALUE=DATE-TIME:20220713T145000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-279@events.sinp.msu.ru DESCRIPTION:Speakers: Semyon Mikheev (Faculty of Physics. M.V.Lomonosov Mo scow State University)\nNeutron stars (NS) are hydrostatically equilibrium stars\, the matter of which consists mainly of neutrons and has a density of the order of the nuclear one. In NS a wide range of extreme states of matter is realized\, therefore study of NS is important not only for astro physics\, but also for nuclear physics. Renewed interest in NS physics has been inspired by first registration of gravitational signal from the merg er of two NS [1]. In recent years radii and masses of a number of NS were measured and NS with large masses were discovered. \nAlthough in the simpl est version the matter of NS consists of neutrons\, protons\, electrons\, and muons\, it is well known that at densities several times higher than t he saturation density of nuclear matter\, hyperons can arise. When the den sity increases\, Λ-hyperons are supposed to be the first to appear\, and we study NS consisting of nucleons\, leptons\, and Λ-hyperons. In this wo rk we focus on the properties of ΛN-interaction\, known from studies of hypernuclei\, and their influence on the characteristics of NS.\nIn order to calculate the equation of state of NS matter we use the self-consistent Skyrme-Hartree-Fock (SHF) model - generally accepted method for describin g baryonic systems [2\,3]. Within this model there are two alternative way s to describe nonlinear effects: dependence on nucleon density $(\\rho^\\a lpha)$ and three-body ΛNN force. These two options are equivalent in symm etric matter if α = 1 and work equally good for hypernuclei. However they are nonequivalent in NS matter and this choice can play a crucial role in calculation of NS characteristics [4]. The choice of α in the density dependence case also can affect these characteristics significantly.\nIn t he present work we examine a number of sets of parameters of hyperon-nucle on and hyperon-hyperon potentials. We calculate different characteristics of NS such as mass\, radius and tidal deformability and investigate their dependence on the properties of interactions.\n\nhttps://events.sinp.msu.r u/event/8/contributions/279/ LOCATION: Физический ф-т\, 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/279/ END:VEVENT BEGIN:VEVENT SUMMARY:SYNTHESIS OF “LIGHT” HEAVY ELEMENTS UNDER EXPLOSION OF LOW-MAS S NEUTRON STAR DTSTART;VALUE=DATE-TIME:20220713T141000Z DTEND;VALUE=DATE-TIME:20220713T143000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-438@events.sinp.msu.ru DESCRIPTION:Speakers: Igor Panov (National Research Center “Kurchatov in stitute”)\nObservation of lantanides in the spectrum of kilonova after gamma-burst and gravitational waves registration [1] confirmed theoretica l r-process scenario [2]\, connected with the neutron star merger (NSM) at the end of close binary system evolution.\nAfter numerous investigation s of the neutron star merger process and following registration of NSM it became definitely clear\, that such a scenario is the main one for formati on of majority heavy nuclei in the r-process. But Neutron stars evolutio n in close binaries depends strongly on their masses. Merger process is in vestigated rather well\, but when masses of stars in close binary differs strongly\, merger scenario develops in different way [3] and nucleosynthes is of heavy elements as well [4]. \nIn present report we considered the nucleosynthesis during the explosion of low-mass component in close bi nary\, which lost its mass due to transfer of matter to the heaviest compo nent and blowing up when hydrodynamically unstable configuration was reach ed [3]. \nThe matter of the exploded remnant is expanding and explosive n ucleosynthesis of new elements takes place before density decrease strongl y. Nucleosynthesis mainly occurs in the mantle layers with initial electro n-to-baryon ratio Ye~0.3-0.4. Nucleosynthesis in the considered scenario was calculated along evolutionary trajectories of passive particles\, conn ected with different mantle zones. Based on fulfilled numerical calculatio ns it was shown that synthesis of heavy elements formed in the r-process i s possible\, at least the light part of them. \nThe work was done under fi nancial support of Russian Science Foundation (project №. 21-12-00061).\ n\n1. N.R. Tanvir\, A.J. Levan\, C. González-Fernández\, et al. // Astro physical Journal. 848. \n L27 (2017).\n2. J. Cowan\, C. Sneden\, J. E. Law ler\, et al. // Rev. Mod. Phys. 93. id. 015002. (2021).\n3. S. I. Blinnik ov\, D. K. Nadyozhin\, N. I. Kramarev\, A. V. Yudin // Astronomy Reports. 65. 385. (2021).\n4. I.V. Panov\, A.V. Yudin // Astronomy Letters. 46. 51 8. (2020).\n\nhttps://events.sinp.msu.ru/event/8/contributions/438/ LOCATION: Физический ф-т\, 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/438/ END:VEVENT BEGIN:VEVENT SUMMARY:DETERMINATION OF PARAMETERS OF THE MODEL WITH THREE STERILE NEUTRI NOS ON THE BASE OF EXPERIMENT BEST RESULTS DTSTART;VALUE=DATE-TIME:20220713T132000Z DTEND;VALUE=DATE-TIME:20220713T134000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-443@events.sinp.msu.ru DESCRIPTION:Speakers: Viacheslav Khruschov (Kurchatov Institute)\nIt is ca rried out evaluations of parameters values for the model with three active and three sterile neutrinos [1]\, namely\, mixing parameters between acti ve and sterile neutrinos and sterile neutrinos masses. When doing that\, r esults of the BEST experiment (Baksan Experiment on Sterile Transitions) a re used [2]. The BEST experiment intends to verification of the gallium an omaly at short distances\, that is the deficit of electron neutrinos from radioactive sources. Besides it is taken into account experimental results concerning verification of accelerator [3] and reactor [4\, 5] neutrino a nomalies at short distances\, as well some astrophysical data [6\, 7].\n\n 1. V.V. Khruschov and S.V. Fomichev // Universe 8\, 97 (2022). \n2. V.V. Barinov et al. // arXiv: 2201.07364\, PP. 1-25 (2022).\n3. A.A. Aguilar-A revalo et al. // Phys. Rev. D 103\, 052002 (2021). \n4. I. Alekseev et al. // Phys. Lett. B 787\, 56 (2018). \n5. A.P. Serebrov et al. // Phys. Rev. D 104\, 032003 (2021). \n6. A. Schneider // Phys. Rev. D 98\, 063021 (20 18).\n7. A. Boyarsky et al. // Prog. Part. Nucl. Phys. 104\, 1 (2019).\n\n https://events.sinp.msu.ru/event/8/contributions/443/ LOCATION: Физический ф-т\, ауд 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/443/ END:VEVENT BEGIN:VEVENT SUMMARY:A modified quasiparticle model in the expansion of early universe of quark gluon plasma DTSTART;VALUE=DATE-TIME:20220713T130000Z DTEND;VALUE=DATE-TIME:20220713T132000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-466@events.sinp.msu.ru DESCRIPTION:Speakers: Yogesh Kumar (Deshbandhu College\, University of Del hi\, Kalkaji\, New Delhi)\nA modified quasiparticle model approach is used in the expansion of early universe of quark gluon plasma. We also used Fr iedmann equation to determine the precise time evolution of the thermodyna mic parameters in the early universe of quark gluon plasma (QGP). The outp ut for time variation of the energy density and the time evolution of temp erature using finite value of thermal dependent quark mass have plotted. T he results show the time evolution of the early universe which also helps in the calculations of other thermodynamic variables like energy density\, pressure\, entropy etc. This provides deep understanding for the evolutio n of early universe of quark gluon plasma.\n\nhttps://events.sinp.msu.ru/e vent/8/contributions/466/ LOCATION: Физический ф-т\, ауд 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/466/ END:VEVENT BEGIN:VEVENT SUMMARY:ON THE POSSIBILITY OF USING THE QUANTUM-FIELD APPROACH TO MODELING THE INTERACTION OF MATTER WITH NEUTRINOS TO STUDY THEIR ROLE IN ASTROPHYSICAL PROCESSES DTSTART;VALUE=DATE-TIME:20220713T124000Z DTEND;VALUE=DATE-TIME:20220713T130000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-407@events.sinp.msu.ru DESCRIPTION:Speakers: Yury М. Pismak (Department of High Energy and El ementary Particle Physics\, State University of Saint-Petersburg\,)\n**st rong text**\n\nhttps://events.sinp.msu.ru/event/8/contributions/407/ LOCATION: Физический ф-т\, ауд 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/407/ END:VEVENT BEGIN:VEVENT SUMMARY:Baryon-antibaryon Asymmetry in p-p\, p-A collisions and String Jun ction Torus as Baryonium DM DTSTART;VALUE=DATE-TIME:20220713T122000Z DTEND;VALUE=DATE-TIME:20220713T124000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-507@events.sinp.msu.ru DESCRIPTION:Speakers: Olga Piskunova (P.N.Lebedev Physics Institute of RAS )\nThe asymmetry of baryon/antibaryon production has been measured in many proton-proton\, pion-proton and electron-proton experiments. In the frame work of Quark-Gluon String Model (QGSM) the energy dependence of asymmetry tells us about the value of $\\alpha_{SJ}$(0)\, the intercept of String J unction Regge trajectory. In previous QGSM study\, the value of intercept has been estimated as 0.5 < $\\alpha_{SJ}$(0) < 0.9. Here\, SJ behaviors a re accumulated in the model based on topological expansion in order to bui ld a neutral object with zero baryon charge. By the way\, QCD mass falling under the event horizon of Black Hole (BH) should be symmetric\, or in ot her words\, have no charge information. The baryon junctions are easily co mbinable with antibaryon ones in hexagons. Topologically\, hexagon net can coherently cover only the torus surface. The net on the torus has discret e number of baryon/antibaryon junctions. This is only parameter that marks the mass/energy level of this object. It looks like DM particle\, is not it? In high energy collisions at LHC\, such pomeron loops are to be produc ed approximately in 1.2 percent of inelastic events. Furthermore\, the tor us configurations of matter have been revealed in many bright events in sp ace. As an example\, Chandra experiment has detected such dense "doughnut" near the event horizon of Super Massive Black Hole (SMBH)\, which X-ray r adiation is screened on 40 percent's. This topological symmetry model of D M seems rather realistic and can help us to deal with an "arm wrestling" b etween the stiffness of toroid structure of QCD matter and the pressure of gravitational singularity at extremely heavy masses. On the other hand\, the instabilities in structure of matter in SMBHs can cause the bursts of giant relativistic hadron jets with the masses of order the own BH mass.\n \nhttps://events.sinp.msu.ru/event/8/contributions/507/ LOCATION: Физический ф-т\, ауд 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/507/ END:VEVENT BEGIN:VEVENT SUMMARY:Testing of the high-energy $\\pi$ and K meson production by the p rimary cosmic protons and helium nuclei DTSTART;VALUE=DATE-TIME:20220713T120000Z DTEND;VALUE=DATE-TIME:20220713T122000Z DTSTAMP;VALUE=DATE-TIME:20260513T191559Z UID:indico-contribution-36-427@events.sinp.msu.ru DESCRIPTION:Speakers: Anton Lukyashin (MEPhI/MSU)\nThe primary cosmic part icles with very high energies are initiating huge cascades of various seco ndary particles in the atmosphere. The atmospheric muon spectrum at energi es from 100 up to $10^{5}$ GeV is formed in decays of the most energetic $ \\pi$ and K mesons produced by the primary protons and more heavy nuclei w ith energies above the threshold and up to $10^{7}$ GeV. The primary nucle i may be regarded as a flux of nucleons. A sophisticated scheme of simulat ions of the atmospheric vertical muon flux has been elaborated. The partia l differential energy spectra of the atmospheric vertical muons in the air shower cascades initiated by primary cosmic nucleons with different fixed energies had been simulated with the help of the program package CORSIKA with statistics of $10^{6}$. The suggested scheme of simulations provides a reasonable accuracy at high energies. The eight most popular hadronic in teractions models QGSJET-01\, QGSJET-II-03\, QGSJET-II-04\, DPMJET 2.55\, VENUS 4.12\, EPOS LHC\, SIBYLL 2.1 and SIBYLL 2.3 had been used to estimat e these partial spectra. These partial spectra of muons have been convolve d with the energy spectrum of the primary nucleons to estimate the atmosph eric vertical muon flux. The known calculations of the primary cosmic prot on and helium nuclei spectra produced in the supernova remnants had been n ormalized on the AMS-02 data and tested by PAMELA\, ATIC-2\, CREAM\, ARGO- YBJ\, ARGO-YBJ &FWCTA\, KASCADE\, KASCADE-Grande\, Tunka\, Ice Cube and Te lescope Array TALE data. The energy spectrum of the primary nucleons had b een estimated with the help of these spectra. At last\, the simulated spec trum of the atmospheric vertical muons had been compared with the rather a ccurate measurements of the atmospheric vertical muon spectra at energies above 100 GeV (e.g.\, L3+Cosmic\, MACRO\, LVD\, Ice Cube data). This compa rison had demonstrated that all tested models failed to reproduce the atmo spheric vertical muon flux correctly. The calculated muon fluxes happened to be below data by factors of 1.5 $\\div$ 2. Therefore\, all tested model s underestimate the production of the most energetic charged $\\pi$ and K mesons by the primary cosmic nucleons by the same factors at energies from $10^{2}$ up to $10^{7}$ GeV.\n\nhttps://events.sinp.msu.ru/event/8/contri butions/427/ LOCATION: Физический ф-т\, ауд 5-42 URL:https://events.sinp.msu.ru/event/8/contributions/427/ END:VEVENT END:VCALENDAR