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201. Magnetic field effect on the oxidation of organic substances by molecular oxygen.

Author

Pliss, Evgeny M., Grobov, Aleksey M., Kuzaev, Anton K., and Buchachenko, Anatoly L.

Subjects
*MAGNETIC field effects, *REACTIVE oxygen species, *OXIDATION, *ALKYL radicals, *OXYGEN
Abstract

Magnetic field effect (ME) on certain steps of chain oxidation of organic compounds of different series by molecular oxygen in liquid phase (initiation, chain propagation, and termination) is presented as a function of [O2] in two regimes. At low concentration of oxygen (<1.5 mM), magnetic field accelerates oxidation by 10% to 100%, but at high concentration no magnetic effect is detected. The dominating contribution into the magnetic effect (ME) is provided by reaction of alkyl radicals to oxygen: R• + O2 → RO2•. This reaction is stimulated by the Zeeman interaction which transforms in the encounter pair (R• O2) producing transformation of quartet spin state, which is spin forbidden to react, into the doublet spin state, which is spin allowed. At high concentration of oxygen, this reaction is not a limiting step and provides no magnetic effect on the total rate of oxidation. The dominating contribution into the magnetic effect (ME) is provided by reaction of alkyl radicals to oxygen: R• + O2 ‐> RO2•. This reaction is stimulated by the Zeeman interaction that transforms in the encounter pair (R• O2) producing transformation of quartet spin state, which is spin forbidden to react, into the doublet spin state, which is spin allowed. At high concentration of oxygen, this reaction is not a limiting step and provides no magnetic effect on the total rate of oxidation. [ABSTRACT FROM AUTHOR]

Published
2019
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202. ON THE QUESTION OF THE VECTORS OF CRIMEAN HEMORRHAGIC FEVER

Author

ARMY BIOLOGICAL LABS FREDERICK MD, Grobov, A. G., ARMY BIOLOGICAL LABS FREDERICK MD, and Grobov, A. G.

Abstract

Of the rodents of the Crimea the only one on which we discovered larvae and nymphs of the tick H. marginatum was the hare L. europaeus transsylvanious. When ticks nymphs which had fed on these hares were examined in the laboratory, it was found that the ultravirus of Crimean hemorrhagic fever could be extracted from them. In the autumn season, the hares prefer to lie up and feed on hard fallow ground and by haystacks. It is in these spots that the greatest density of H. marginatum ticks is observed in summer months. These spots also constitute the most dangerous foci for the infection of humans with Crimean hemorrhagic fever. Study of birds in the districts where cases of the fever are reported is of very great significance, both from the point of view of the possibility of their acting as vectors of Crimean hemorrhagic fever and likewise from the point of view of the dissemination of the infected immature stages of H. marginatum ticks., Trans. of Meditsinskaya Parazitologiya i Parazitarnye Bolezni (USSR) v15 n6 p59-63 1946.

Published
1951

203. Study on cosmogenic activation above ground for the DarkSide-20k project

Author

Aaron, E., Agnes, P., Ahmad, I., Albergo, S., Albuquerque, I. F. M., Alexander, T., Alton, A. K., Amaudruz, P., Atzori Corona, M., Ave, M., Avetisov, I. Ch, Azzolini, O., Back, H. O., Balmforth, Z., Barrado-Olmedo, A., Barrillon, P., Basco, A., Batignani, G., Bocci, V., Bonivento, W. M., Bottino, B., Boulay, M. G., Busto, J., Cadeddu, M., Caminata, A., Canci, N., Capra, A., Caprioli, S., Caravati, M., Nicola Cargioli, Carlini, M., Castello, P., Cavalcante, P., Cavuoti, S., Cebrian, S., Ruiz, J. M. Cela, Chashin, S., Chepurnov, A., Chyhyrynets, E., Cifarelli, L., Cintas, D., Citterio, M., Cleveland, B., Cocco, V., Vilda, E. Conde, Consiglio, L., Copello, S., Covone, G., Czubak, M., D Aniello, M., D Auria, S., Da Rocha Rolo, M. D., Davini, S., Cecco, S., Gruttola, D., Pasquale, S., Rosa, G., Dellacasa, G., Derbin, A. V., Devoto, A., Di Capua, F., Di Noto, L., Di Stefano, P., Dolganov, G., Dordei, F., Ellingwood, E., Erjavec, T., Diaz, M. Fernandez, Fiorillo, G., Franchini, P., Franco, D., Funicello, N., Gabriele, F., Gahan, D., Galbiati, C., Gallina, G., Gallus, G., Garbini, M., Abia, P. Garcia, Gendotti, A., Ghiano, C., Giganti, C., Giovanetti, G. K., Casanueva, V. Goicoechea, Gola, A., Grauso, G., Di Cortona, G. Grilli, Grobov, A., Gromov, M., Guan, M., Guerzoni, M., Gulino, M., Guo, C., Hackett, B. R., Hallin, A. L., Hamer, A., Haranczyk, M., Hessel, T., Hill, S., Horikawa, S., Hubaut, F., Hucker, J., Hugues, T., Ianni, An, Ippolito, V., Jillings, C., Jois, S., Kachru, P., Kemp, A. A., Kendziora, C. L., Kimura, M., Kochanek, I., Kondo, K., Korga, G., Koulosousas, S., Kubankin, A., Kuss, M., Kuzniak, M., La Commara, M., Lai, M., Le Guirriec, E., Leason, E., Leoni, A., Lidey, L., Lissia, M., Luzzi, L., Lychagina, O., Macfadyen, O., Machulin, I. N., Manecki, S., Manthos, I., Mapelli, L., Margotti, A., Mari, S. M., Mariani, C., Maricic, J., Marini, A., Martínez, M., Martoff, C. J., Matteucci, G., Mavrokoridis, K., Mcdonald, A. B., Messina, A., Milincic, R., Mitra, A., Moharana, A., Monroe, J., Moretti, E., Morrocchi, M., Mróz, T., Muratova, V. N., Muscas, C., Musico, P., Nania, R., Nessi, M., Nikolopoulos, K., Nowak, J., Olchansky, K., Oleinik, A., Oleynikov, V., Organtini, P., Solórzano, A. Ortiz, Pagani, L., Pallavicini, M., Pandola, L., Pantic, E., Paoloni, E., Paternoster, G., Pegoraro, P. A., Pelczar, K., Pellegrino, C., Pesudo, V., Piacentini, S., Pietrofaccia, L., Pino, N., Pocar, A., Poehlmann, D. M., Pordes, S., Pralavorio, P., Price, D., Ragusa, F., Ramachers, Y., Razeti, M., Renshaw, A. L., Rescigno, M., Retiere, F., Rignanese, L. P., Ripoli, C., Rivetti, A., Roberts, A., Roberts, C., Rode, J., Rogers, G., Romero, L., Rossi, M., Rubbia, A., Sabia, M. A., Salomone, P., Sandford, E., Sanfilippo, S., Santone, D., Santorelli, R., Savarese, C., Scapparone, E., Schillaci, G., Schuckman, Ii F. G., Scioli, G., Simeone, M., Skensved, P., Skorokhvatov, M. D., Smirnov, O., Smirnova, T., Smith, B., Spadoni, F., Spangenberg, M., Stefanizzi, R., Steri, A., Stornelli, V., Stracka, S., Stringer, M., Sulis, S., Sung, A., Suvorov, Y., Szelc, A. M., Tartaglia, R., Taylor, A., Taylor, J., Tedesco, S., Testera, G., Thieme, K., Thorpe, T. N., Tonazzo, A., Tricomi, A., Unzhakov, E. V., John, T. Vallivilayil, Uffelen, M., Viant, T., Viel, S., Vogelaar, R. B., Vossebeld, J., Wada, M., Walczak, M. B., Wang, H., Wang, Y., Westerdale, S., Williams, L., Wingerter-Seez, I., Wojaczynski, R., Wojcik, Ma M., Wright, T., Xie, Y., Yang, C., Zabihi, A., Zakhary, P., Zani, A., Zichichi, A., Zuzel, G., Zykova, M. P., Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and DarkSide-20k

Subjects
Physics - Instrumentation and Detectors, long-lived, FOS: Physical sciences, instrumentation and detectors, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), iron, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], surface, High Energy Physics, titanium, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], time projection chamber, liquid argon, Instrumentation and Methods for Astrophysics (astro-ph.IM), galaxy, dark matter, astro-ph.IM, experiment, physics, background, Instrumentation and Detectors (physics.ins-det), cosmic radiation, copper, argon, direct detection, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The activation of materials due to exposure to cosmic rays may become an important background source for experiments investigating rare event phenomena. DarkSide-20k, currently under construction at the Laboratori Nazionali del Gran Sasso, is a direct detection experiment for galactic dark matter particles, using a two-phase liquid-argon Time Projection Chamber (TPC) filled with 49.7 tonnes (active mass) of Underground Argon (UAr) depleted in 39Ar. Despite the outstanding capability of discriminating gamma/beta background in argon TPCs, this background must be considered because of induced dead time or accidental coincidences mimicking dark-matter signals and it is relevant for low-threshold electron-counting measurements. Here, the cosmogenic activity of relevant long-lived radioisotopes induced in the experiment has been estimated to set requirements and procedures during preparation of the experiment and to check that it is not dominant over primordial radioactivity; particular attention has been paid to the activation of the 120 t of UAr used in DarkSide-20k. Expected exposures above ground and production rates, either measured or calculated, have been considered in detail. From the simulated counting rates in the detector due to cosmogenic isotopes, it is concluded that activation in copper and stainless steel is not problematic. The activity of 39Ar induced during extraction, purification and transport on surface is evaluated to be 2.8% of the activity measured in UAr by DarkSide-50 experiment, which used the same underground source, and thus considered acceptable. Other isotopes in the UAr such as 37Ar and 3H are shown not to be relevant due to short half-life and assumed purification methods., Comment: As accepted for publication at Astroparticle Physics

204. The Large Enriched Germanium Experiment for Neutrinoless $\beta\beta$ Decay

Author

Abgrall, N., Abt, I., Agostini, M., Alexander, A., Andreoiu, C., Araujo, G. R., Avignone, F. T., Bae, W., Bakalyarov, A., Balata, M., Bantel, M., Barabanov, I., Barabash, A. S., Barbeau, P. S., Barton, C. J., Barton, P. J., Laura Baudis, Bauer, C., Bernieri, E., Bezrukov, L., Bhimani, K. H., Biancacci, V., Blalock, E., Bolozdynya, A., Borden, S., Bos, B., Bossio, E., Boston, A., Bothe, V., Bouabid, R., Boyd, S., Brugnera, R., Burlac, N., Busch, M., Caldwell, A., Caldwell, T. S., Carney, R., Cattadori, C., Chan, Y. -D, Chernogorov, A., Christofferson, C. D., Chu, P. -H, Clark, M., Cohen, T., Combs, D., Comellato, T., Cooper, R. J., Costa, I. A., D Andrea, V., Detwiler, J. A., Di Giacinto, A., Di Marco, N., Dobson, J., Drobizhev, A., Durand, M. R., Edzards, F., Efremenko, Yu, Elliott, S. R., Engelhardt, A., Fajt, L., Faud, N., Febbraro, M. T., Ferella, F., Fields, D. E., Fischer, F., Fomina, M., Fox, H., Franchi, J., Gala, R., Galindo-Uribarri, A., Gangapshev, A., Garfagnini, A., Geraci, A., Gilbert, C., Gold, M., Gooch, C., Gradwohl, K. P., Green, M. P., Grinyer, G. F., Grobov, A., Gruszko, J., Guinn, I., Guiseppe, V. E., Gurentsov, V., Gurov, Y., Gusev, K., Hacket, B., Hagemann, F., Hakenmüeller, J., Haranczyk, M., Hauertmann, L., Haufe, C. R., Hayward, C., Heffron, B., Henkes, F., Henning, R., Aguilar, D. Hervas, Hinton, J., Hodak, R., Hoffmann, H., Hofmann, W., Hostiuc, A., Huang, J., Hult, M., Mirza, M. Ibrahim, Jochum, J., Jones, R., Judson, D., Junker, M., Kaizer, J., Kazalov, V., Kermaïdic, Y., Khushbakht, H., Kidd, M., Kihm, T., Kilgus, K., Kim, I., Klimenko, A., Knöpfle, K. T., Kochetov, O., Konovalov, S. I., Kontul, I., Kool, K., Kormos, L. L., Kornoukhov, V. N., Korosec, M., Krause, P., Kuzminov, V. V., López-Castaño, J. M., Lang, K., Laubenstein, M., León, E., Lehnert, B., Leonhardt, A., Li, A., Lindner, M., Lippi, I., Liu, X., Liu, J., Loomba, D., Lubashevskiy, A., Lubsandorzhiev, B., Lusardi, N., Müller, Y., Macko, M., Macolino, C., Majorovits, B., Mamedov, F., Maneschg, W., Manzanillas, L., Marshall, G., Martin, R. D., Martin, E. L., Massarczyk, R., Mei, D., Meijer, S. J., Mertens, S., Misiaszek, M., Mondragon, E., Morella, M., Morgan, B., Mroz, T., Muenstermann, D., Nave, C. J., Nemchenok, I., Neuberger, M., Oli, T. K., Gann, G. Orebi, Othman, G., Palušova, V., Panth, R., Papp, L., Paudel, L. S., Pelczar, K., Perez, J. Perez, Pertoldi, L., Pettus, W., Piseri, P., Poon, A. W. P., Povinec, P., Pullia, A., Radford, D. C., Ramachers, Y. A., Ransom, C., Rauscher, L., Redchuk, M., Reine, A. L., Riboldi, S., Rielage, K., Rozov, S., Rukhadze, E., Rumyantseva, N., Runge, J., Ruof, N. W., Saakyan, R., Sailer, S., Salamanna, G., Salamida, F., Salvat, D. J., Sandukovsky, V., Schönert, S., Schültz, A., Schütt, M., Schaper, D. C., Schreiner, J., Schulz, O., Schuster, M., Schwarz, M., Schwingenheuer, B., Selivanenko, O., Shaflee, M., Shevchik, E., Shirchenko, M., Shitov, Y., Simgen, H., Simkovic, F., Skorokhvatov, M., Slavickova, M., Smolek, K., Smolnikov, A., Solomon, J. A., Song, G., Starosta, K., Stekl, I., Stommel, M., Stukov, D., Sumathi, R. R., Sweigart, D. A., Szczepaniec, K., Taffarello, L., Tagnani, D., Tayloe, R., Tedeschi, D., Turqueti, M., Varner, R. L., Vasilyev, S., Veresnikova, A., Vetter, K., Vignoli, C., Vogl, C., Sturm, K., Waters, D., Waters, J. C., Wei, W., Wiesinger, C., Wilkerson, J. F., Willers, M., Wiseman, C., Wojcik, M., Wu, V. H. -S, Xu, W., Yakushev, E., Ye, T., Yu, C. -H, Yumatov, V., Zaretski, N., Zeman, J., Zhitnikov, I., Zinatulina, D., Zschocke, A. -K, Zsigmond, A. J., Zuber, K., and Zuzel, G.

205. The DEAP-3600 Experiment

Author

Stringer, M., Adhikari, P., Ajaj, R., Alpízar-Venegas, M., Auty, D. J., Benmansour, H., Bina, C. E., Bonivento, W., Boulay, M. G., Matteo Cadeddu, Cai, B., Cárdenas-Montes, M., Cavuoti, S., Chen, Y., Cleveland, B. T., Corning, J. M., Daugherty, S., Delgobbo, P., Di Stefano, P., Doria, L., Dunford, M., Ellingwood, E., Erlandson, A., Farahani, S. S., Fatemighomi, N., Fiorillo, G., Gallacher, D., García Abia, P., Garg, S., Giampa, P., Goeldi, D., Gorel, P., Graham, K., Grobov, A., Hallin, A. L., Hamstra, M., Hugues, T., Ilyasov, A., Joy, A., Jigmeddorj, B., Jillings, C. J., Kamaev, O., Kaur, G., Kemp, A., Kochanek, I., Kuźniak, M., Lai, M., Langrock, S., Lehnert, B., Leonhardt, A., Levashko, N., Li, X., Lissia, M., Litvinov, O., Lock, J., Longo, G., Machulin, I., Mcdonald, A. B., Mcelroy, T., Mclaughlin, J. B., Mielnichuk, C., Mirasola, L., Monroe, J., Oliviéro, G., Pal, S., Peeters, S. J. M., Perry, M., Pesudo, V., Picciau, E., Piro, M. -C, Pollmann, T. R., Rand, E. T., Rethmeier, C., Retière, F., Rodríguez-García, I., Roszkowski, L., Ruhland, J. B., Sanchez García, E., Sánchez-Pastor, T., Santorelli, R., Seth, S., Sinclair, D., Skensved, P., Smith, B., Smith, N. J. T., Sonley, T., Stainforth, R., Sur, B., Vázquez-Jáuregui, E., Viel, S., Walding, J., Waqar, M., Ward, M., Westerdale, S., Willis, J., and Zuñiga-Reyes, A.

206. Inhomogeneous compact extra dimensions

Author

Bronnikov K.A., Budaev R.I., Grobov A.V., Dmitriev A.E., Rubin S.G., Bronnikov K.A., Budaev R.I., Grobov A.V., Dmitriev A.E., and Rubin S.G.

Abstract

We show that an inhomogeneous compact extra space possesses two necessary features - their existence does not contradict the observable value of the cosmological constant Lambda(4) in pure f(R) theory, and the extra dimensions are stable relative to the "radion mode" of perturbations, the only mode considered. For a two-dimensional extra space, both analytical and numerical solutions for the metric are found, able to provide a zero or arbitrarily small Lambda(4). A no-go theorem has also been proved, that maximally symmetric compact extra spaces are inconsistent with 4D Minkowski space in the framework of pure f(R) gravity.

207. Local heating of the universe by the Higgs field

Author

Belotsky K., Grobov A., Rubin S., Belotsky K., Grobov A., and Rubin S.

Abstract

© 2018 World Scientific Publishing Company It is shown that the creation of primordial massive black holes is accompanied by a local heating of the matter. The developed mechanism is based on the interaction of the Higgs field and a scalar field responsible for black hole formation. We also consider dynamical behavior of parameters such as a scale and chemical composition of such heating regions.

208. Local heating of the universe by the Higgs field

Author

Belotsky K., Grobov A., Rubin S., Belotsky K., Grobov A., and Rubin S.

Abstract

© 2018 World Scientific Publishing Company It is shown that the creation of primordial massive black holes is accompanied by a local heating of the matter. The developed mechanism is based on the interaction of the Higgs field and a scalar field responsible for black hole formation. We also consider dynamical behavior of parameters such as a scale and chemical composition of such heating regions.

216. Catalytic inhibition of olefin oxidation with Mn and Cu compounds.

Author

Pliss, E. M., Machtin, V. A., Tikhonov, I. V., Sirik, A. V., Grobov, A. M., and Yasinsky, O. A.

Subjects
*TRANSITION metal compounds, *HYDROXYL group, *OXIDATION
Abstract

The rate constants and kinetic coefficients of inhibition (fkin) for olefins oxidized with the transition metal compounds (Mn) were measured by highly sensitive microvolumometry at 323 K in combination with kinetic modeling. The cyclic mechanism of the reactions of hydroxyl radicals with Mn leading to the multiple chain termination was confirmed as indicated by the observed effect of long-term inhibition of the oxidation of the substrates with Mn and obtained values of fkin > 102. [ABSTRACT FROM AUTHOR]

Published
2021
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217. Search for Dark Matter Particle Interactions with Electron Final States with DarkSide-50.

Author

Agnes P, Albuquerque IFM, Alexander T, Alton AK, Ave M, Back HO, Batignani G, Biery K, Bocci V, Bonivento WM, Bottino B, Bussino S, Cadeddu M, Cadoni M, Calaprice F, Caminata A, Campos MD, Canci N, Caravati M, Cargioli N, Cariello M, Carlini M, Cataudella V, Cavalcante P, Cavuoti S, Chashin S, Chepurnov A, Cicalò C, Covone G, D'Angelo D, Davini S, De Candia A, De Cecco S, De Filippis G, De Rosa G, Derbin AV, Devoto A, D'Incecco M, Dionisi C, Dordei F, Downing M, D'Urso D, Fiorillo G, Franco D, Gabriele F, Galbiati C, Ghiano C, Giganti C, Giovanetti GK, Goretti AM, Grilli di Cortona G, Grobov A, Gromov M, Guan M, Gulino M, Hackett BR, Herner K, Hessel T, Hosseini B, Hubaut F, Hungerford EV, Ianni A, Ippolito V, Keeter K, Kendziora CL, Kimura M, Kochanek I, Korablev D, Korga G, Kubankin A, Kuss M, La Commara M, Lai M, Li X, Lissia M, Longo G, Lychagina O, Machulin IN, Mapelli LP, Mari SM, Maricic J, Messina A, Milincic R, Monroe J, Morrocchi M, Mougeot X, Muratova VN, Musico P, Nozdrina AO, Oleinik A, Ortica F, Pagani L, Pallavicini M, Pandola L, Pantic E, Paoloni E, Pelczar K, Pelliccia N, Piacentini S, Pocar A, Poehlmann DM, Pordes S, Poudel SS, Pralavorio P, Price DD, Ragusa F, Razeti M, Razeto A, Renshaw AL, Rescigno M, Rode J, Romani A, Sablone D, Samoylov O, Sands W, Sanfilippo S, Sandford E, Savarese C, Schlitzer B, Semenov DA, Shchagin A, Sheshukov A, Skorokhvatov MD, Smirnov O, Sotnikov A, Stracka S, Suvorov Y, Tartaglia R, Testera G, Tonazzo A, Unzhakov EV, Vishneva A, Vogelaar RB, Wada M, Wang H, Wang Y, Westerdale S, Wojcik MM, Xiao X, Yang C, and Zuzel G

Abstract

We present a search for dark matter particles with sub-GeV/c^{2} masses whose interactions have final state electrons using the DarkSide-50 experiment's (12 306±184)  kg d low-radioactivity liquid argon exposure. By analyzing the ionization signals, we exclude new parameter space for the dark matter-electron cross section σ[over ¯]&#95;{e}, the axioelectric coupling constant g&#95;{Ae}, and the dark photon kinetic mixing parameter κ. We also set the first dark matter direct-detection constraints on the mixing angle |U&#95;{e4}|^{2} for keV/c^{2} sterile neutrinos.

Published
2023
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218. Search for Dark-Matter-Nucleon Interactions via Migdal Effect with DarkSide-50.

Author

Agnes P, Albuquerque IFM, Alexander T, Alton AK, Ave M, Back HO, Batignani G, Biery K, Bocci V, Bonivento WM, Bottino B, Bussino S, Cadeddu M, Cadoni M, Calaprice F, Caminata A, Campos MD, Canci N, Caravati M, Cargioli N, Cariello M, Carlini M, Cataudella V, Cavalcante P, Cavuoti S, Chashin S, Chepurnov A, Cicalò C, Covone G, D'Angelo D, Davini S, De Candia A, De Cecco S, De Filippis G, De Rosa G, Derbin AV, Devoto A, D'Incecco M, Dionisi C, Dordei F, Downing M, D'Urso D, Fairbairn M, Fiorillo G, Franco D, Gabriele F, Galbiati C, Ghiano C, Giganti C, Giovanetti GK, Goretti AM, Grilli di Cortona G, Grobov A, Gromov M, Guan M, Gulino M, Hackett BR, Herner K, Hessel T, Hosseini B, Hubaut F, Hungerford EV, Ianni A, Ippolito V, Keeter K, Kendziora CL, Kimura M, Kochanek I, Korablev D, Korga G, Kubankin A, Kuss M, La Commara M, Lai M, Li X, Lissia M, Longo G, Lychagina O, Machulin IN, Mapelli LP, Mari SM, Maricic J, Messina A, Milincic R, Monroe J, Morrocchi M, Mougeot X, Muratova VN, Musico P, Nozdrina AO, Oleinik A, Ortica F, Pagani L, Pallavicini M, Pandola L, Pantic E, Paoloni E, Pelczar K, Pelliccia N, Piacentini S, Pocar A, Poehlmann DM, Pordes S, Poudel SS, Pralavorio P, Price DD, Ragusa F, Razeti M, Razeto A, Renshaw AL, Rescigno M, Rode J, Romani A, Sablone D, Samoylov O, Sandford E, Sands W, Sanfilippo S, Savarese C, Schlitzer B, Semenov DA, Shchagin A, Sheshukov A, Skorokhvatov MD, Smirnov O, Sotnikov A, Stracka S, Suvorov Y, Tartaglia R, Testera G, Tonazzo A, Unzhakov EV, Vishneva A, Vogelaar RB, Wada M, Wang H, Wang Y, Westerdale S, Wojcik MM, Xiao X, Yang C, and Zuzel G

Abstract

Dark matter elastic scattering off nuclei can result in the excitation and ionization of the recoiling atom through the so-called Migdal effect. The energy deposition from the ionization electron adds to the energy deposited by the recoiling nuclear system and allows for the detection of interactions of sub-GeV/c^{2} mass dark matter. We present new constraints for sub-GeV/c^{2} dark matter using the dual-phase liquid argon time projection chamber of the DarkSide-50 experiment with an exposure of (12 306±184)  kg d. The analysis is based on the ionization signal alone and significantly enhances the sensitivity of DarkSide-50, enabling sensitivity to dark matter with masses down to 40  MeV/c^{2}. Furthermore, it sets the most stringent upper limit on the spin independent dark matter nucleon cross section for masses below 3.6  GeV/c^{2}.

Published
2023
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219. First Direct Detection Constraints on Planck-Scale Mass Dark Matter with Multiple-Scatter Signatures Using the DEAP-3600 Detector.

Author

Adhikari P, Ajaj R, Alpízar-Venegas M, Auty DJ, Benmansour H, Bina CE, Bonivento W, Boulay MG, Cadeddu M, Cai B, Cárdenas-Montes M, Cavuoti S, Chen Y, Cleveland BT, Corning JM, Daugherty S, DelGobbo P, Di Stefano P, Doria L, Dunford M, Ellingwood E, Erlandson A, Farahani SS, Fatemighomi N, Fiorillo G, Gallacher D, García Abia P, Garg S, Giampa P, Goeldi D, Gorel P, Graham K, Grobov A, Hallin AL, Hamstra M, Hugues T, Ilyasov A, Joy A, Jigmeddorj B, Jillings CJ, Kamaev O, Kaur G, Kemp A, Kochanek I, Kuźniak M, Lai M, Langrock S, Lehnert B, Leonhardt A, Levashko N, Li X, Lissia M, Litvinov O, Lock J, Longo G, Machulin I, McDonald AB, McElroy T, McLaughlin JB, Mielnichuk C, Mirasola L, Monroe J, Oliviéro G, Pal S, Peeters SJM, Perry M, Pesudo V, Picciau E, Piro MC, Pollmann TR, Raj N, Rand ET, Rethmeier C, Retière F, Rodríguez-García I, Roszkowski L, Ruhland JB, Sanchez García E, Sánchez-Pastor T, Santorelli R, Seth S, Sinclair D, Skensved P, Smith B, Smith NJT, Sonley T, Stainforth R, Stringer M, Sur B, Vázquez-Jáuregui E, Viel S, Walding J, Waqar M, Ward M, Westerdale S, Willis J, and Zuñiga-Reyes A

Abstract

Dark matter with Planck-scale mass (≃10^{19}  GeV/c^{2}) arises in well-motivated theories and could be produced by several cosmological mechanisms. A search for multiscatter signals from supermassive dark matter was performed with a blind analysis of data collected over a 813 d live time with DEAP-3600, a 3.3 t single-phase liquid argon-based detector at SNOLAB. No candidate signals were observed, leading to the first direct detection constraints on Planck-scale mass dark matter. Leading limits constrain dark matter masses between 8.3×10^{6} and 1.2×10^{19}  GeV/c^{2}, and ^{40}Ar-scattering cross sections between 1.0×10^{-23} and 2.4×10^{-18}  cm^{2}. These results are interpreted as constraints on composite dark matter models with two different nucleon-to-nuclear cross section scalings.

Published
2022
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220. Pulse-shape discrimination against low-energy Ar-39 beta decays in liquid argon with 4.5 tonne-years of DEAP-3600 data.

Author

Adhikari P, Ajaj R, Alpízar-Venegas M, Amaudruz PA, Auty DJ, Batygov M, Beltran B, Benmansour H, Bina CE, Bonatt J, Bonivento W, Boulay MG, Broerman B, Bueno JF, Burghardt PM, Butcher A, Cadeddu M, Cai B, Cárdenas-Montes M, Cavuoti S, Chen M, Chen Y, Cleveland BT, Corning JM, Cranshaw D, Daugherty S, DelGobbo P, Dering K, DiGioseffo J, Di Stefano P, Doria L, Duncan FA, Dunford M, Ellingwood E, Erlandson A, Farahani SS, Fatemighomi N, Fiorillo G, Florian S, Flower T, Ford RJ, Gagnon R, Gallacher D, García Abia P, Garg S, Giampa P, Goeldi D, Golovko V, Gorel P, Graham K, Grant DR, Grobov A, Hallin AL, Hamstra M, Harvey PJ, Hearns C, Hugues T, Ilyasov A, Joy A, Jigmeddorj B, Jillings CJ, Kamaev O, Kaur G, Kemp A, Kochanek I, Kuźniak M, Lai M, Langrock S, Lehnert B, Leonhardt A, Levashko N, Li X, Lidgard J, Lindner T, Lissia M, Lock J, Longo G, Machulin I, McDonald AB, McElroy T, McGinn T, McLaughlin JB, Mehdiyev R, Mielnichuk C, Monroe J, Nadeau P, Nantais C, Ng C, Noble AJ, O'Dwyer E, Oliviéro G, Ouellet C, Pal S, Pasuthip P, Peeters SJM, Perry M, Pesudo V, Picciau E, Piro MC, Pollmann TR, Rand ET, Rethmeier C, Retière F, Rodríguez-García I, Roszkowski L, Ruhland JB, Sánchez-García E, Santorelli R, Sinclair D, Skensved P, Smith B, Smith NJT, Sonley T, Soukup J, Stainforth R, Stone C, Strickland V, Stringer M, Sur B, Tang J, Vázquez-Jáuregui E, Viel S, Walding J, Waqar M, Ward M, Westerdale S, Willis J, and Zuñiga-Reyes A

Abstract

The DEAP-3600 detector searches for the scintillation signal from dark matter particles scattering on a 3.3 tonne liquid argon target. The largest background comes from 39 Ar beta decays and is suppressed using pulse-shape discrimination (PSD). We use two types of PSD estimator: the prompt-fraction, which considers the fraction of the scintillation signal in a narrow and a wide time window around the event peak, and the log-likelihood-ratio, which compares the observed photon arrival times to a signal and a background model. We furthermore use two algorithms to determine the number of photons detected at a given time: (1) simply dividing the charge of each PMT pulse by the mean single-photoelectron charge, and (2) a likelihood analysis that considers the probability to detect a certain number of photons at a given time, based on a model for the scintillation pulse shape and for afterpulsing in the light detectors. The prompt-fraction performs approximately as well as the log-likelihood-ratio PSD algorithm if the photon detection times are not biased by detector effects. We explain this result using a model for the information carried by scintillation photons as a function of the time when they are detected., (© The Author(s) 2021.)

Published
2021
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221. [An intranasal meningoencephalocele in a 64-year-old woman].

Author

Bykova VP, Grobov AO, Kuznetsova IL, and Serbina VI

Subjects
Diagnosis, Differential, Encephalocele surgery, Female, Humans, Meningocele surgery, Middle Aged, Nasal Cavity, Nasal Polyps pathology, Nasal Polyps surgery, Encephalocele pathology, Meningocele pathology
Abstract

The paper reports a rare case of intranasal meningoencephalocele in a 64-year-old female, simulating clinically a nasal polyp. A histological investigation of the removed polyp showed that it was composed mainly of malformed brain tissue with meninx vasculosa. The authors suggest a congenital nature of this formation.

Published
1993

222. [A case of secondary syphilis simulating plasmocytoma].

Author

Bykova VP, Abramova EI, and Grobov AO

Subjects
Adult, Diagnosis, Differential, Humans, Immunoglobulins analysis, Male, Mouth Mucosa immunology, Mouth Mucosa pathology, Mouth Neoplasms immunology, Plasma Cells immunology, Plasma Cells pathology, Plasmacytoma immunology, Recurrence, Stomatitis immunology, Stomatitis pathology, Syphilis immunology, Syphilis Serodiagnosis, Syphilis, Cutaneous immunology, Syphilis, Cutaneous pathology, Mouth Neoplasms pathology, Plasmacytoma pathology, Syphilis pathology
Abstract

A clinically unclear case is described of stomatitis with a long duration in a male of 28. Exfoliations in the region of the mouth angle were observed resembling pemphigus vegetans. Biopsy examination revealed a thick plasma cell infiltration which was considered to be an extramedullary plasmacytoma. However, a polyclonal composition of plasmacytes was found immunomorphologically producing immunoglobulins A, M and G with predominant production of IgG. This allowed rejection of neoplastic nature of the infiltrate, confirming its inflammatory origin and specific character. Serological tests (Wassermann, immunofluorescence test, in vitro immobilization test) confirmed the diagnosis of secondary recurring syphilis. Differential diagnosis of plasma-cell syphilid of skin and mucosal extramedullary plasmacytoma is under discussion.

Published
1991

223. [A case of tubercular laryngopharyngitis diagnosed by biopsy].

Author

Bykova VP, Antonova NA, and Grobov AO

Subjects
Biopsy, Humans, Hypopharynx pathology, Male, Middle Aged, Necrosis, Pharyngitis microbiology, Tuberculosis, Laryngeal diagnosis, Pharyngitis pathology, Tuberculosis, Laryngeal pathology
Abstract

A 47-year-old man had ulcero-necrotic pharyngitis examined and treated without effect in various Moscow hospitals for 3 months. The diagnosis was established after histologic and bacteriologic examination of the biopsy.

Published
1991

224. [Characteristics of immunity in children with lymphoid hyperplastic diathesis].

Author

Sannikova NE, Bykova VP, and Grobov AO

Subjects
Castleman Disease complications, Child, Preschool, Humans, Hypertrophy, Immunologic Deficiency Syndromes diagnosis, Infant, Leukocyte Count, Thymus Hyperplasia complications, Castleman Disease immunology, Immunoglobulins analysis, Immunologic Deficiency Syndromes etiology, Palatine Tonsil pathology, T-Lymphocytes immunology, Thymus Hyperplasia immunology
Abstract

As many as 100 children aged 3 months to 4 years with lymphaticohypoplastic diathesis (LHD) were examined for clinico-immunologic++ interrelations. The children suffering from manifest LHD demonstrated the reduction of the amount of circulating T lymphocytes and IgA, IgM and IgG subpopulations. At the same time the changes in local immunity correlating with enlargement of the thymus and lymphoid formations in the nasopharynx were identified. The immunity unbalance in LHD was supported by morphologic and immunologic studies of the tissue of the removed hypertrophied tonsils. The specification of the deranged mechanisms of immunity in LHD requires early diagnosis of the illness, screening of the methods for immunocorrection and closer follow-up of the sick children.

Published
1989

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