Low energy effects of neutrino masses

While all models of Majorana neutrino masses lead to the same dimension five effective operator, which does not conserve lepton number, the dimension six operators induced at low energies conserve lepton number and differ depending on the high energy model of new physics. We derive the low-energy dimension six operators which are characteristic of generic Seesaw models, in which neutrino masses result from the exchange of heavy fields which may be either fermionic singlets, fermionic triplets or scalar triplets. The resulting operators may lead to effects observable in the near future, if the coefficients of the dimension five and six operators are decoupled along a certain pattern, which turns out to be common to all models. The phenomenological consequences are explored as well, including their contributions to $\mu \to e \gamma$ and new bounds on the Yukawa couplings for each model.Comment: modifications: couplings in appendix B, formulas (121)-(122) on rare leptons decays (to match with published version) and consequently bounds in table

LEADER 3—Lipase and Amylase Activity in Subjects With Type 2 Diabetes: Baseline Data From Over 9000 Subjects in the LEADER Trial

Objectives: This report from the LEADER (Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results) trial describes baseline lipase and amylase activity in type 2 diabetic subjects without acute pancreatitis symptoms before randomization to the glucagonlike peptide analog liraglutide or placebo. Methods: The LEADER is an international randomized placebo-controlled trial evaluating the cardiovascular safety of liraglutide in 9340 type 2 diabetic patients at high cardiovascular risk. Fasting lipase and amylase activity was assessed at baseline, before receiving liraglutide or placebo, using a commercial assay (Roche) with upper limit of normal values of 63 U/L for lipase and 100 U/L for amylase. Results: Either or both enzymes were above the upper limit of normal in 22.7% of subjects; 16.6% (n = 1540) had an elevated lipase level (including 1.2% >3-fold elevated), and 11.8% (n = 1094) had an elevated amylase level (including 0.2% >3-fold elevated). In multivariable regression models, severely reduced kidney function was associated with the largest effect on increasing activity of both. However, even among subjects with normal kidney function, 12.2% and 7.7% had elevated lipase and amylase levels. Conclusions: In this large study of type 2 diabetic patients, nearly 25% had elevated lipase or amylase levels without symptoms of acute pancreatitis. The clinician must take these data into account when evaluating abdominal symptoms in type 2 diabetic patients

LEADER 3: Lipase and amylase activity in subjects with type 2 diabetes

Objectives: This report from the LEADER (Liraglutide Effect and Action in Diabetes: Evaluation of Cardiovascular Outcome Results) trial describes baseline lipase and amylase activity in type 2 diabetic subjects without acute pancreatitis symptoms before randomization to the glucagonlike peptide analog liraglutide or placebo. Methods: The LEADER is an international randomized placebo-controlled trial evaluating the cardiovascular safety of liraglutide in 9340 type 2 diabetic patients at high cardiovascular risk. Fasting lipase and amylase activity was assessed at baseline, before receiving liraglutide or placebo, using a commercial assay (Roche) with upper limit of normal values of 63 U/L for lipase and 100 U/L for amylase. Results: Either or both enzymes were above the upper limit of normal in 22.7% of subjects; 16.6% (n = 1540) had an elevated lipase level (including 1.2% \u3e3-fold elevated), and 11.8% (n = 1094) had an elevated amylase level (including 0.2% \u3e3-fold elevated). In multivariable regression models, severely reduced kidney function was associated with the largest effect on increasing activity of both. However, even among subjects with normal kidney function, 12.2% and 7.7% had elevated lipase and amylase levels. Conclusions: In this large study of type 2 diabetic patients, nearly 25% had elevated lipase or amylase levels without symptoms of acute pancreatitis. The clinician must take these data into account when evaluating abdominal symptoms in type 2 diabetic patients

Group space scan of flavor symmetries for nearly tribimaximal lepton mixing

We present a systematic group space scan of discrete Abelian flavor symmetries for lepton mass models that produce nearly tribimaximal lepton mixing. In our models, small neutrino masses are generated by the type-I seesaw mechanism. The lepton mass matrices emerge from higher-dimension operators via the Froggatt-Nielsen mechanism and are predicted as powers of a single expansion parameter \epsilon that is of the order of the Cabibbo angle \theta_C\simeq 0.2. We focus on solutions that can give close to tribimaximal lepton mixing with a very small reactor angle \theta_{13}\approx 0 and find several thousand explicit such models that provide an excellent fit to current neutrino data. The models are rather general in the sense that large leptonic mixings can come from the charged leptons and/or neutrinos. Moreover, in the neutrino sector, both left- and right-handed neutrinos can mix maximally. We also find a new relation \theta_{13}\lesssim\epsilon^3 for the reactor angle and a new sum rule \theta_{23}\approx\pi/4+\epsilon/\sqrt{2} for the atmospheric angle, allowing the models to be tested in future neutrino oscillation experiments.Comment: 18 pages, 2 tables, 2 figures, references added, final version to appear in JHE

Quark helicity distributions from longitudinal spin asymmetries in muon-proton and muon-deuteron scattering

Double-spin asymmetries for production of charged pions and kaons in semi-inclusive deep-inelastic muon scattering have been measured by the COMPASS experiment at CERN. The data, obtained by scattering a 160 GeV muon beam off a longitudinally polarised NH_3 target, cover a range of the Bjorken variable x between 0.004 and 0.7. A leading order evaluation of the helicity distributions for the three lightest quarks and antiquark flavours derived from these asymmetries and from our previous deuteron data is presented. The resulting values of the sea quark distributions are small and do not show any sizable dependence on x in the range of the measurements. No significant difference is observed between the strange and antistrange helicity distributions, both compatible with zero. The integrated value of the flavour asymmetry of the helicity distribution of the light-quark sea, \Delta u-bar - \Delta d-bar, is found to be slightly positive, about 1.5 standard deviations away from zero.Comment: 13 pages, 5 figure

Leading order determination of the gluon polarisation from DIS events with high-p_T hadron pairs

We present a determination of the gluon polarisation Delta g/g in the nucleon, based on the longitudinal double-spin asymmetry of DIS events with a pair of large transverse-momentum hadrons in the final state. The data were obtained by the COMPASS experiment at CERN using a 160 GeV/c polarised muon beam scattering off a polarised ^6LiD target. The gluon polarisation is evaluated by a Neural Network approach for three intervals of the gluon momentum fraction x_g covering the range 0.04 < x_g < 0.27. The values obtained at leading order in QCD do not show any significant dependence on x_g. Their average is Delta g/g = 0.125 +/- 0.060 (stat.) +/- 0.063 (syst.) at x_g=0.09 and a scale of mu^2 = 3 (GeV/c)^2.Comment: 13 pages, 6 figures and 3 table

Measurement of the Longitudinal Spin Transfer to Lambda and Anti-Lambda Hyperons in Polarised Muon DIS

The longitudinal polarisation transfer from muons to lambda and anti-lambda hyperons, D_LL, has been studied in deep inelastic scattering off an unpolarised isoscalar target at the COMPASS experiment at CERN. The spin transfers to lambda and anti-lambda produced in the current fragmentation region exhibit different behaviours as a function of x and xF . The measured x and xF dependences of D^lambda_LL are compatible with zero, while D^anti-lambda_LL tends to increase with xF, reaching values of 0.4 - 0.5. The resulting average values are D^lambda_LL = -0.012 +- 0.047 +- 0.024 and D^anti-lambda_LL = 0.249 +- 0.056 +- 0.049. These results are discussed in the frame of recent model calculations.Comment: 13 pages, 7 figure

Implementation of the type III seesaw model in FeynRules/MadGraph and prospects for discovery with early LHC data

We discuss the implementation of the "minimal" type III seesaw model, i.e. with one fermionic triplet, in FeynRules/MadGraph. This is the first step in order to realize a real study of LHC data recorded in the LHC detectors. With this goal in mind, we comment on the possibility of discovering this kind of new physics at the LHC running at 7 TeV with a luminosity of few fb^-1.Comment: 28 pages, 7 figures, Tables with cross sections are updated, a channel was missing. Version to appear on Eur. Phys. J.