628 research outputs found

    Analysis of a model with a common source of CP violation

    Full text link
    We work in a model where all CP violating phenomena have a common source. CP is spontaneously broken at a large scale VV through the phase of a complex singlet scalar. An additional SU(2)LSU(2)_L singlet vector-like down-type quark relates this high scale CP violation to low energy. We quantitatively analyze this model in the quark sector. We obtain the numerical values of the parameters of the Lagrangian in the quark sector for a specific ansatz of the 4×44\times4 down-type quark mass matrix where the weak phase is generated minimally. ZbˉbZ \bar b b vertex will modify in presence of the extra vector-like down-type quark. From the experimental lower bound of the partial decay width ZbˉbZ\to \bar b b we find out the lower bound of the additional down-type quark mass. Tree level flavor changing neutral current appears in this model due to the presence of the extra vector-like down-type quark. We give the range of values of the mass splitting ΔmBq\Delta m_{B_q} in Bq0Bˉq0B^0_q-{\bar B}^0_q system using SM box, ZZ mediating tree level and ZZ mediating one loop diagrams together for both q=d,sq=d, s. We find out the analytical expression for Γ12q\Gamma_{12}^q in this model from standard box, ZZ and Higgs mediated penguin diagrams for Bq0Bˉq0B^0_q-{\bar B}^0_q system, q=d,sq=d,s. From this we numerically evaluate the decay width difference ΔΓBq/ΓBq|\Delta\Gamma_{B_q}/\Gamma_{B_q}|. We also find out the numerical values of the CP asymmetry parameters aJa_J and aπa_\pi for the decays Bd0J/ψKsB^0_d\to J/\psi K_s and Bd0π+πB^0_d\to \pi^+ \pi^- respectively. We get the lower bound of the scale VV through the upper bound of the strong CP phase.Comment: 20 pages, no figures New materials and references have been added. Text has been modified. To be appear in J.Phys.

    Investigation and implications of spatial and temporal patterns in sex ratio data from West Greenland minke whale catches.

    Get PDF
    The sub-group based its deliberations on the computations set out below, which were carried out by Givens following input from sub-group members

    Evidence and patterns of tuna spawning inside a large no-take marine protected area

    Get PDF
    © The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Hernandez, C. M., Witting, J., Willis, C., Thorrold, S. R., Llopiz, J. K., & Rotjan, R. D. Evidence and patterns of tuna spawning inside a large no-take marine protected area. Scientific Reports, 9(1), (2019): 10772, doi:10.1038/s41598-019-47161-0.The Phoenix Islands Protected Area (PIPA), one of the world’s largest marine protected areas, represents 11% of the exclusive economic zone of the Republic of Kiribati, which earns much of its GDP by selling tuna fishing licenses to foreign nations. We have determined that PIPA is a spawning area for skipjack (Katsuwonus pelamis), bigeye (Thunnus obesus), and yellowfin (Thunnus albacares) tunas. Our approach included sampling larvae on cruises in 2015–2017 and using a biological-physical model to estimate spawning locations for collected larvae. Temperature and chlorophyll conditions varied markedly due to observed ENSO states: El Niño (2015) and neutral (2016–2017). However, larval tuna distributions were similar amongst years. Generally, skipjack larvae were patchy and more abundant near PIPA’s northeast corner, while Thunnus larvae exhibited lower and more even abundances. Genetic barcoding confirmed the presence of bigeye (Thunnus obesus) and yellowfin (Thunnus albacares) tuna larvae. Model simulations indicated that most of the larvae collected inside PIPA in 2015 were spawned inside, while stronger currents in 2016 moved more larvae across PIPA’s boundaries. Larval distributions and relative spawning output simulations indicated that both focal taxa spawned inside PIPA in all 3 study years, demonstrating that PIPA is protecting viable tuna spawning habitat.Funding and support was provided by the PIPA Trust, Waitt and Oceans5 Foundations, Sea Education Association, the Prince Albert of Monaco Foundation II, New England Aquarium, and Boston University to R.R. and J.W. C.H. was additionally supported by a National Science Foundation Graduate Research Fellowship. J.L. was additionally supported by NOAA through the Cooperative Institute for the North Atlantic Region (CINAR) under Cooperative Agreement NA14OAR4320158 in the form a CINAR Fellow Award, as well as by the WHOI Academic Programs Office. We thank A. Breef-Pilz for onboard sampling assistance, as well as S. Glancy, J. Pringle, E. Martin, J. Fisher, H. Goss, J. Jaskiel, S. Sheehan, and C. Moller for lab assistance. We thank the PIPA Trust and the PIPA Implementation Office for their support, as well as on-ship Kiribati Observers for their support and assistance: Tekeua Auatabu, Iannang Teaioro, Toaea Beiateuea, Taremon Korere, Kareati Waysang, and Moamoa Kabuati. We thank Q. Hanich for reading sections of this paper in advance. This research was conducted under Kiribati and PIPA permits PRP #s 3/17, 1/16, and 2/15 to JW

    Physical Acoustics

    Get PDF
    Contains reports on four research projects.U. S. Navy (Office of Naval Research) under Contract Nonr- 1841(42

    Ocular, bulbar, limb, and cardiopulmonary involvement in oculopharyngeal muscular dystrophy

    Get PDF
    OBJECTIVES: To assess skeletal muscle weakness and progression as well as the cardiopulmonary involvement in oculopharyngeal muscular dystrophy (OPMD). MATERIALS AND METHODS: Cross-sectional study including symptomatic patients with genetically confirmed OPMD. Patients were assessed by medical history, ptosis, ophthalmoplegia, facial and limb strength, and swallowing capability. Cardiopulmonary function was evaluated using forced expiratory capacity in 1 s (FEV1), electrocardiogram (ECG), Holter monitoring, and echocardiography. RESULTS: We included 13 symptomatic patients (six males, mean age; 64 years (41-80) from 8 families. Ptosis was the first symptom in 8/13 patients followed by limb weakness in the remaining 5 patients Dysphagia was never the presenting symptom. At the time of examination, all affected patients had ptosis or had previously been operated for ptosis, while ophthalmoplegia was found in 9 patients. Dysphagia, tested by cold-water swallowing test, was abnormal in 9 patients (17-116 s, ref <8 s). Six patients could not climb stairs of whom two were wheelchair bound and one used a rollator. Six patients had reduced FEV1 (range 23%-59%). No cardiac involvement was identified. CONCLUSIONS: Limiting limb weakness is common in OPMD and can even be the presenting symptom of the disease. In contrast, dysphagia was not the initial symptom in any of our patients, although it was obligatory for diagnosing OPMD before genetic testing became available. Mild respiratory dysfunction, but no cardiac involvement, was detected

    Generation and characterization of isolated attosecond pulses at 100  kHz repetition rate

    Get PDF
    The generation of coherent light pulses in the extreme ultraviolet (XUV) spectral region with attosecond pulse durations constitutes the foundation of the field of attosecond science. Twenty years after the first demonstration of isolated attosecond pulses, they continue to be a unique tool enabling the observation and control of electron dynamics in atoms, molecules, and solids. It has long been identified that an increase in the repetition rate of attosecond light sources is necessary for many applications in atomic and molecular physics, surface science, and imaging. Although high harmonic generation (HHG) at repetition rates exceeding 100 kHz, showing a continuum in the cutoff region of the XUV spectrum, was already demonstrated in 2013, the number of photons per pulse was insufficient to perform pulse characterization via attosecond streaking, let alone to perform a pump-probe experiment. Here we report on the generation and full characterization of XUV attosecond pulses via HHG driven by near-single-cycle pulses at a repetition rate of 100 kHz. The high number of 106 XUV photons per pulse on target enables attosecond electron streaking experiments through which the XUV pulses are determined to consist of a dominant single attosecond pulse. These results open the door for attosecond pump-probe spectroscopy studies at a repetition rate 1 or 2 orders of magnitude above current implementations

    Liturgijski vid naputka Ad resurgendum cum Christo

    Get PDF
    This study was funded by the Greenland Bureau of Minerals and Petroleum, the Danish Cooperation of the Environment in the Arctic (DANCEA, Danish Ministry of the Environment) and the Greenland Institute of Natural Resources.Decisions about sustainable exploitation levels of marine resources are often based on inadequate data, but are nevertheless required for practical purposes. We describe one exception where abundance estimates spanning 30 years and catch data spanning more than 40 years were used in a Bayesian assessment model of belugas Delphinapterus leucas off West Greenland. The model was updated with data from a visual aerial survey on the wintering ground in 2012. Methods that take account of stochastic animal availability by using independent estimates of forward and perpendicular sighting distances were used to estimate beluga abundance. A model that appears to be robust to the presence of a few large groups yielded an estimate of 7456 belugas (cv = 0.44), similar to a conventional distance-sampling estimate. A mark–recapture distance analysis that corrects for perception and availability bias estimated the abundance to be 9072 whales (cv = 0.32). Increasing distance of beluga sightings from shore was correlated with decreasing sea ice cover, suggesting that belugas expand their distribution offshore (i.e. westward in this context) with the reduction of coastal sea ice. A model with high (0.98) adult survival estimated a decline from 18 600 (90% CI: 13 400, 26 000) whales in 1970 to 8000 (90% CI: 5830, 11 200) in 2004. The decline was probably a result of a period with exceptionally large catches. Following the introduction of catch limits in 2004, the model projects an increase to 11 600 (90% CI: 6760, 17 600) individuals in 2020 (assuming annual removals of 294 belugas after 2014). If the annual removal level is fixed at 300 individuals, a low-survival (0.97) model predicts a 75% probability of an increasing population during 2015–2020. Reduced removal rates due to catch limits and the more offshore, less accessible distribution of the whales are believed to be responsible for the initial signs of population recovery.Publisher PDFPeer reviewe

    Plasma Electronics

    Get PDF
    Contains reports on twelve research projectsU. S. NavyU.S. Navy (Office of Naval Research) under Contract Nonr-1841(78)U. S. Air Force under Air Force Contract AF 19(604)-7400U. S. ArmyNational Science Foundation (Grant G-24073)Lincoln Laboratory, Purchase Order DDL B-0036
    corecore