28 research outputs found

    Updated MiniBooNE Neutrino Oscillation Results with Increased Data and New Background Studies

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    The MiniBooNE experiment at Fermilab reports a total excess of 638.0±132.8638.0 \pm 132.8 electron-like events (4.8σ4.8 \sigma) from a data sample corresponding to 18.75×102018.75 \times 10^{20} protons-on-target in neutrino mode, which is a 46% increase in the data sample with respect to previously published results, and 11.27×102011.27 \times 10^{20} protons-on-target in antineutrino mode. The additional statistics allow several studies to address questions on the source of the excess. First, we provide two-dimensional plots in visible energy and cosine of the angle of the outgoing lepton, which can provide valuable input to models for the event excess. Second, we test whether the excess may arise from photons that enter the detector from external events or photons exiting the detector from π0\pi^0 decays in two model independent ways. Beam timing information shows that almost all of the excess is in time with neutrinos that interact in the detector. The radius distribution shows that the excess is distributed throughout the volume, while tighter cuts on the fiducal volume increase the significance of the excess. We conclude that models of the event excess based on entering and exiting photons are disfavored.Comment: 22 pages, 18 figure

    NEXT-CRAB-0: A High Pressure Gaseous Xenon Time Projection Chamber with a Direct VUV Camera Based Readout

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    The search for neutrinoless double beta decay (0νββ0\nu\beta\beta) remains one of the most compelling experimental avenues for the discovery in the neutrino sector. Electroluminescent gas-phase time projection chambers are well suited to 0νββ0\nu\beta\beta searches due to their intrinsically precise energy resolution and topological event identification capabilities. Scalability to ton- and multi-ton masses requires readout of large-area electroluminescent regions with fine spatial resolution, low radiogenic backgrounds, and a scalable data acquisition system. This paper presents a detector prototype that records event topology in an electroluminescent xenon gas TPC via VUV image-intensified cameras. This enables an extendable readout of large tracking planes with commercial devices that reside almost entirely outside of the active medium.Following further development in intermediate scale demonstrators, this technique may represent a novel and enlargeable method for topological event imaging in 0νββ0\nu\beta\beta.Comment: 32 Pages, 22 figure

    Measurement of the (π\pi^-, Ar) total hadronic cross section at the LArIAT experiment

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    We present the first measurement of the negative pion total hadronic cross section on argon, which we performed at the Liquid Argon In A Testbeam (LArIAT) experiment. All hadronic reaction channels, as well as hadronic elastic interactions with scattering angle greater than 5~degrees are included. The pions have a kinetic energies in the range 100-700~MeV and are produced by a beam of charged particles impinging on a solid target at the Fermilab Test Beam Facility. LArIAT employs a 0.24~ton active mass Liquid Argon Time Projection Chamber (LArTPC) to measure the pion hadronic interactions. For this measurement, LArIAT has developed the ``thin slice method", a new technique to measure cross sections with LArTPCs. While generally higher than the prediction, our measurement of the (π\pi^-,Ar) total hadronic cross section is in agreement with the prediction of the Geant4 model when considering a model uncertainty of \sim5.1\%.Comment: 15 pages, 15 figures, 3 tables, accepted by PR

    The Liquid Argon In A Testbeam (LArIAT) Experiment

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    The LArIAT liquid argon time projection chamber, placed in a tertiary beam of charged particles at the Fermilab Test Beam Facility, has collected large samples of pions, muons, electrons, protons, and kaons in the momentum range 300-1400 MeV/c. This paper describes the main aspects of the detector and beamline, and also reports on calibrations performed for the detector and beamline components

    A Compact Dication Source for Ba2+^{2+} Tagging and Heavy Metal Ion Sensor Development

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    We present a tunable metal ion beam that delivers controllable ion currents in the picoamp range for testing of dry-phase ion sensors. Ion beams are formed by sequential atomic evaporation and single or multiple electron impact ionization, followed by acceleration into a sensing region. Controllability of the ionic charge state is achieved through tuning of electrode potentials that influence the retention time in the ionization region. Barium, lead, and cobalt samples have been used to test the system, with ion currents identified and quantified using a quadrupole mass analyzer. Realization of a clean Ba2+\mathrm{Ba^{2+}} ion beam within a bench-top system represents an important technical advance toward the development and characterization of barium tagging systems for neutrinoless double beta decay searches in xenon gas. This system also provides a testbed for investigation of novel ion sensing methodologies for environmental assay applications, with dication beams of Pb2+^{2+} and Cd2+^{2+} also demonstrated for this purpose

    In vitro micropropagation from immature embryos of the endemic and endangered Muscari muscarimi Medik

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    An efficient in vitro bulblet production procedure from immature zygotic embryos of endemic and endangered Muscari muscarimi Medik. was described in the current study. Zygotic embryos were first isolated from immature seeds and cultured on different nutrient media compositions supplemented with various combinations of ?-naphthalene acetic acid (NAA), picloram, dicamba, 6-benzylaminopurine (BAP), and thidiazuron (TDZ). The best bulblet regeneration (59 bulblets per explant) was achieved in Murashige and Skoog (MS) medium containing 4 mg/L BAP and 0.5 mg/L NAA after 1 year of culture initiation. Regenerated bulblets were then transferred into MS medium without plant growth regulators for rooting. Bulblets produced well-developed root systems and increased their size on this medium after 2 months. All rooted bulblets were successfully transplanted into a potting mixture and acclimatized to ambient conditions. © TÜBİTAK

    Y-chromosome polymorphisms in 12 native, Karagül, Karacabey merino breeds from Turkey and Anatolian mouflon (Ovis gmelinii anatolica) [Türkiye’den 12 yerli, karagül, karacabey merinosu ve anadolu yaban koyununda (Ovis gmelinii anatolica) Y-Kromozom polimorfizmleri]

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    In this study, 182 male animals from 12 native sheep breeds, as well as Karacabey Merino and Karagül breeds of Anatolia, wild sheep Anatolian Mouflon (Ovis gmelinii anatolica) were used as the study material. Based on SRY and SRYM18 regions on the Y-chromosome, haplotypes of the populations were analyzed using DNA sequence analyses. The SRY region, A-oY1 allele was observed in all of the individuals studied. On the other hand, four different alleles corresponding to four Y-chromosome haplotypes were detected at the SRYM18 microsatellite region. Among native Anatolian breeds (n=143), H6 haplotype (80.41%), H4 haplotype (9.09%), H8 haplotype (8.40%) and H12 haplotype (2.1%) were identified. H6 haplotype was observed in all 16 individuals of Ovis gmelinii anatolica. Pairwise FST values based on haplotype frequencies were calculated for domestic sheep, and the highest FST value was observed between Karagül and Kıvırcık along with Karagül and Ovis gmelinii anatolica with pairwise FST value of 0.43202 (P<0.01). Y chromosome polymorphism of sheep from Turkey were examined comparatively with the accumulated data in the literature. Out of seven haplotypes (H4, H5, H6, H7, H8, H12, H19) observed in Europe and Asia, 4 haplotypes (H4, H6, H8 and H12) were observed in Anatolia. H12 was a private haplotype of Sakız, H6 seems to be the predominant haplotype of domestic sheep (79.51%) as well as being the only haplotype observed in Ovis gmelini anatolica. H4 haplotype seemed to be associated with fat tailed sheep migrating to Turkey, entering from south east of Turkey, which may be related with the arrival of nomadic Turks. © 2018, Veteriner Fakultesi Dergisi. All rights reserved.BAP-01-08-2012-014 1176 BAP-01-08-2012-014[1] The present study was supported by both Harran University [project number: 1176] and Middle East Technical University [project number: BAP-01-08-2012-014] -- The present study was supported by both Harran University Scientific Research Committee with the project number 1176 and Middle East Technical University project number BAP-01-08-2012-014. -

    Adventitious shoot regeneration and micropropagation of Plantago lanceolata L.

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    Shoot regeneration from hypocotyl and cotyledon explants of Plantago lanceolata treated with various concentrations of Benzylaminopurine (BAP) and Indole 3 butyric acid in MS medium was significantly influenced by the amounts of BAP and IBA in concentration and explantdependent manner: Micropropagation was accomplished using various concentrations of BAP + IBA, kinetin + IBA and TDZ + IBA. Micropropagated shoots were rooted on the MS medium containing 2.69 mu M NAA. Plants were acclimatized and transferred to greenhouse, where they flowered and set seed
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