2221. Measurement of the proton-air cross section with Telescope Array's Black Rock Mesa and Long Ridge fluorescence detectors, and surface array in hybrid modeR. U. Abbasi, Mitsuhiro Abe, T. Abu-Zayyad, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, Douglas R. Bergman, S. A. Blake, Jon Paul Lundquist, 2020, original scientific article Abstract: Ultra high energy cosmic rays provide the highest known energy source in the universe to measure proton cross sections. Though conditions for collecting such data are less controlled than an
accelerator environment, current generation cosmic ray observatories have large enough exposures to collect significant statistics for a reliable measurement for energies above what can be attained in the lab. Cosmic ray measurements of cross section use atmospheric calorimetry to measure depth of air shower maximum (Xmax), which is related to the primary particle’s energy and mass. The tail of the Xmax distribution is assumed to be dominated by showers generated by protons, allowing measurement of the inelastic proton-air cross section. In this work the proton-air inelastic
cross section measurement, σ_inel_p−air, using data observed by Telescope Array’s Black Rock Mesa and Long Ridge fluorescence detectors and surface detector array in hybrid mode is presented. σ_inel_p−air is observed to be 520.1 ± 35.8 [Stat.] +25.0 −40 [Sys.] mb at √s = 73 TeV. The total proton-proton cross section is subsequently inferred from Glauber formalism and is found to be σ_tot_pp = 139.4 +23.4−21.3[Stat.] +15.0−24.0[Sys.] mb.
Keywords: cosmic rays, astroparticles, proton-air cross section
Published in RUNG: 04.02.2021; Views: 2421; Downloads: 0
This document has many files! More... |
2222. Observations of the origin of downward terrestrial gamma-ray flashesJ. W. Belz, P. R. Krehbiel, J. Remington, M. A. Stanley, R. U. Abbasi, R. LeVon, W. Rison, D. Rodeheffer, T. Abu-Zayyad, Jon Paul Lundquist, 2020, original scientific article Abstract: In this paper we report the first close, high‐resolution observations of downward‐directed terrestrial gamma‐ray flashes (TGFs) detected by the large‐area Telescope Array cosmic ray observatory, obtained in conjunction with broadband VHF interferometer and fast electric field change measurements of the parent discharge. The results show that the TGFs occur during strong initial breakdown pulses (IBPs) in the first few milliseconds of negative cloud‐to‐ground and low‐altitude intracloud flashes and that the IBPs are produced by a newly identified streamer‐based discharge process called fast negative breakdown. The observations indicate the relativistic runaway electron avalanches (RREAs) responsible for producing the TGFs are initiated by embedded spark‐like transient conducting events (TCEs) within the fast streamer system and potentially also by individual fast streamers themselves. The TCEs are inferred to be the cause of impulsive sub‐pulses that are characteristic features of classic IBP sferics. Additional development of the avalanches would be facilitated by the enhanced electric field ahead of the advancing front of the fast negative breakdown. In addition to showing the nature of IBPs and their enigmatic sub‐pulses, the observations also provide a possible explanation for the unsolved question of how the streamer to leader transition occurs during the initial negative breakdown, namely, as a result of strong currents flowing in the final stage of successive IBPs, extending backward through both the IBP itself and the negative streamer breakdown preceding the IBP.
Keywords: terrestrial gamma-ray flashes, lightning, fast breakdown, initial breakdown pulse, atmospheric electricity, transient conducting events
Published in RUNG: 04.02.2021; Views: 2530; Downloads: 21
 Link to full text
This document has many files! More... |
2223. |
2224. Post-Covid recovery of the Cultural and Creative Industries in the Adriatic-Ionian RegionPeter Purg, Dora Ruždjak Podolski, NIhad Kreševljaković, Sehad Čekić, Goran Tomka, Marija Katalinić, unpublished conference contribution Keywords: recovery, art, innovation, culture, creative
Published in RUNG: 03.02.2021; Views: 2294; Downloads: 0
This document has many files! More... |
2225. Photodegradation mechanisms of reactive blue 19 dye under UV and simulated solar light irradiationZeinab Ebrahimpour, Olena Pliekhova, Humberto Cabrera, Mahmoud Abdelhamid, Dorota Korte, Komlan Segbéya Gadedjisso-Tossou, Joseph J. Niemela, Urška Lavrenčič Štangar, Mladen Franko, 2021, original scientific article Keywords: reactive blue 19, photocatalytic, photosensitization, thermal lens, UV-Vis
Published in RUNG: 02.02.2021; Views: 2581; Downloads: 0
This document has many files! More... |
2226. |
2227. Stoichiometry and disorder influence over electronic structure in nanostructured VO[sub]x filmsAlessandro D'Elia, S. J. Rezvani, Nicola Zema, F. Zuccaro, Mattia Fanetti, Blaž Belec, B. W. Li, C. W. Zou, Carlo Spezzani, Maurizio Sacchi, Augusto Marcelli, Marcello Coreno, 2021, original scientific article Keywords: nanoparticles, VOx films, electronic structure, nanostructured films
Published in RUNG: 31.01.2021; Views: 2448; Downloads: 0
This document has many files! More... |
2228. Ezikov transfer v oblastta na pragmatikata : predavanje na Inštitutu za bolgarski jezik, Sofija, Bolgarija, 28. 1. 2021Penka Stateva, 2021, invited lecture at foreign university Abstract: n this talk I will present work in progress that aims to explore a previously uncharted area of multilingual language acquisition, which concerns negative linguistic transfer in the domain of pragmatics. The research is part of a larger program in experimental pragmatics which aims to identify points of cross-linguistic diversion that affect meaning. We investigate the impact of language variation on bilingual acquisition of grammatical number in pairs of languages like Lebanese Arabic and French, and Slovenian-Italian, in which the interpretation of plural morphology within each pair is different depending on whether the number paradigm also includes dual number or not.
Keywords: negative transfer, plural interpretation, anti-duality, pragmatic enrichment
Published in RUNG: 29.01.2021; Views: 2569; Downloads: 0
This document has many files! More... |
2229. Why kl~kolj, br~ber, v~ved, but never kl~br or kolj~ber? : restrictions on the phonological shape of root allomorphs in SlovenianPetra Mišmaš, Marko Simonović, 2021, published scientific conference contribution abstract Keywords: Slovenian, phonology, morphology, verbs, root allomorphy, theme vowels
Published in RUNG: 29.01.2021; Views: 2381; Downloads: 69
Link to full text
This document has many files! More... |
2230. In-situ XAS study of catalytic N[sub]2O decomposition over CuO/CeO[sub]2 catalystsMaxim Zabilsky, Iztok Arčon, Petar Djinović, Elena Tchernychova, Albin Pintar, 2021, original scientific article Abstract: We performed in‐situ XAS study of N 2 O decomposition over CuO/CeO 2 catalysts. The Cu K‐edge and Ce L 3 ‐edge XANES and EXAFS analyses revealed the dynamic and crucial role of Cu 2+ /Cu + and Ce 4+ /Ce 3+ ionic pairs during the catalytic reaction. We observed the initial formation of reduced Cu + and Ce 3+ species during activation in helium atmosphere at 400 °C, while concentration of these species decreased significantly during steady‐state nitrous oxide degradation reaction (2500 ppm N 2 O in He at 400 °C). In‐situ EXAFS analysis further revealed a crucial role of copper‐ceria interface in this catalytic reaction. We observed dynamic changes in average number of Cu‐Ce scatters under reaction conditions, indicating an enlarging the interface between both copper and ceria phases, where electron and oxygen transfer occurs.
Keywords: in-situ XAS, Cu EXAFS, CuO/CeO2 nanorod catalys, N2O decomposition
Published in RUNG: 29.01.2021; Views: 3027; Downloads: 0
This document has many files! More... |
