21 research outputs found

    The Case for a Muon Collider Higgs Factory

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    We propose the construction of a compact Muon Collider Higgs Factory. Such a machine can produce up to \sim 14,000 at 8\times 10^{31} cm^-2 sec^-1 clean Higgs events per year, enabling the most precise possible measurement of the mass, width and Higgs-Yukawa coupling constants.Comment: Supporting letter for the document: "Muon Collider Higgs Factory for Smowmass 2013", A White Paper submitted to the 2013 U.S. Community Summer Study of the Division of Particles and Fields of the American Physical Society, Y. Alexahin, et. al, FERMILAB-CONF-13-245-T (July, 2013

    An ancient bison from the mouth of the Rauchua River (Chukotka, Russia)

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    An incomplete carcass of an extinct bison, Bison ex gr. priscus, was discovered in 2012 in the mouth of the Rauchua River (69°30'N, 166°49'E), Chukotka. The carcass included the rump with two hind limbs, ribs, and large flap of hide from the abdomen and sides, several vertebrae, bones of the forelimbs and anterior autopodia, stomach with its contents, and wool. The limb bones are relatively gracile, which is unusual in bison, and a SEM study of the hair microstructure suggests higher insulating capacity than in extant members of the genus. Additionally, mitochondrial DNA analyses indicate that the Rauchua bison belonged to a distinct and previously unidentified lineage of steppe bison. Two radiocarbon dates suggest a Holocene age for the bison: a traditional 14C date provided an estimate of 8030±70 14C yr BP (SPb-743) and an AMS radiocarbon date provided an age of 9497±92 14C yr BP (AA101271). These dates make this the youngest known bison from Chukotka. Analysis of stomach contents revealed a diet of herbaceous plants (meadow grasses and sedges) and shrubs, suggesting that the early Holocene vegetation near the mouth of the Rauchua River was similar to that of the present day: tundra-associated vegetation with undersized plants

    CCIM Technology for Treatment of LILW and HLW -10209

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    ABSTRACT Cold Crucible Inductive Melting (CCIM) technology is developed and applied at SIA Radon for vitrification of low-and intermediate-level radioactive wastes (LILW). During last eight years SIA Radon researchers were dealing with application of CCIM for vitrification of high level wastes (HLW). HLW surrogates of Savannah River Site (SRS), USA, and Production Association (PA) "Mayak", Russia, were vitrified and products were examined in details. CCIM operational conditions and process variables (feed rate, melt rate, melting ratio, etc.) were determined. Feasibility of vitrification of HLW with high aluminum and iron contents has been proven. Various types of pumps to feed slurries into the crucible were tested. Maximum waste loading in glass keeping its high chemical durability was determined. The heat balance in the system "high frequency generator -crucible" was summarized and effective power spent for batch melting and melt homogenization was measured. Since 2007 design and construction works on cold crucible for HLW treatment were carried out. Previous experience in cold crucible design and operation experience during vitrification of actual LILW and HLW surrogates were applied. Principles of operation and control of the inductive melter were formulated. Automated control system has been designed and a set of the equipment required has been completed. The new cold crucible with the automated control system and auxiliary equipment is recommended for implementation at PA "Mayak" for study of HLW vitrification process of both spent nuclear fuel (SNF) reprocessing and old ("historical") tanks with variable chemical composition

    X-ray Excited Optical Luminescence of Eu in Diamond Crystals Synthesized at High Pressure High Temperature

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    Powder diamonds with integrated europium atoms were synthesized at high pressure (7.7 GPa) and temperature (1800 °C) from a mixture of pentaerythritol with pyrolyzate of diphthalocyanine (C64H32N16Eu) being a special precursor. In diamonds prepared by X-ray fluorescence spectroscopy, we have found a concentration of Eu atoms of 51 ± 5 ppm that is by two orders of magnitude greater than that in natural and synthetic diamonds. X-ray diffraction, SEM, X-ray exited optical luminescence, and Raman and IR spectroscopy have confirmed the formation of high-quality diamond monocrystals containing Eu and a substantial amount of nitrogen (~500 ppm). Numerical simulation has allowed us to determine the energy cost of 5.8 eV needed for the incorporation of a single Eu atom with adjacent vacancy into growing diamond crystal (528 carbons)

    Exploring time like tranistions in pp, πp and AA reactions with HADES

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    Radiative transition of an excited baryon to a nucleon with emission of a virtual massive photon converting to dielectron pair (Dalitz decays) provides important information about baryon-photon coupling at low q2 in timelike region. A prominent enhancement in the respective electromagnetic transition Form Factors (etFF) at q2 near vector mesons ρ/ω poles has been predicted by various calculations reflecting strong baryon-vector meson couplings. The understanding of these couplings is also of primary importance for the interpretation of the emissivity of QCD matter studied in heavy ion collisions via dilepton emission. Dedicated measurements of baryon Dalitz decays in proton-proton and pion-proton scattering with HADES detector at GSI/FAIR are presented and discussed. The relevance of these studies for the interpretation of results obtained from heavy ion reactions is elucidated on the example of the HADES results

    Resonance production in p+p, p+A and A+A collisions measured with HADES

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    The knowledge of baryonic resonance properties and production cross sections plays an important role for the extraction and understanding of medium modifications of mesons in hot and/or dense nuclear matter. We present and discuss systematics on dielectron and strangeness production obtained with HADES on p+p, p+A and A+A collisions in the few GeV energy regime with respect to these resonances
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