0000000000759117
AUTHOR
Federico Mescia
Axion search with BabyIAXO in view of IAXO
Axions are a natural consequence of the Peccei-Quinn mechanism, the most compelling solution to the strong-CP problem. Similar axion-like particles (ALPs) also appear in a number of possible extensions of the Standard Model, notably in string theories. Both axions and ALPs are very well motivated candidates for Dark Matter, and in addition, they would be copiously produced at the sun's core. A relevant effort during the last decade has been the CAST experiment at CERN, the most sensitive axion helioscope to-date. The International Axion Observatory (IAXO) is a large-scale 4th generation helioscope. As its primary physics goal, IAXO will look for solar axions or ALPs with a signal to backgro…
Non-perturbatively renormalised light quark masses from a lattice simulation with Nf=2
Abstract We present results for the light quark masses obtained from a lattice QCD simulation with N f = 2 degenerate Wilson dynamical quark flavours. The sea quark masses of our lattice, of spacing a ≃ 0.06 fm , are relatively heavy, i.e., they cover the range corresponding to 0.60 ≲ M P / M V ≲ 0.75 . After implementing the non-perturbative RI-MOM method to renormalise quark masses, we obtain m ud MS ¯ ( 2 GeV ) = 4.3 ± 0.4 −0 +1.1 MeV , and m s MS ¯ ( 2 GeV ) = 101 ± 8 −0 +25 MeV , which are about 15% larger than they would be if renormalised perturbatively. In addition, we show that the above results are compatible with those obtained in a quenched simulation with a similar lattice.
Flavor physics in the quark sector
218 páginas, 106 figuras, 89 tablas.-- arXiv:0907.5386v2.-- Report of the CKM workshop, Rome 9-13th Sep. 2008.-- et al.
BK-parameter fromNf=2twisted mass lattice QCD
We present an unquenched Nf=2 lattice computation of the B K parameter which controls K0-K0 oscillations. A partially quenched setup is employed with two maximally twisted dynamical (sea) light Wi ...
Non-perturbatively renormalised light quark masses from a lattice simulation with N(f) = 2
We present results for the light quark masses obtained from a lattice QCD simulation with N-f = 2 degenerate Wilson dynamical quark flavours. The sea quark masses of our lattice, of spacing a similar or equal to 0.06 fm, are relatively heavy, i.e., they cover the range corresponding to 0.60 less than or similar to M-p/M-V less than or similar to 0.75. After implementing the non-perturbative RI-MOM method to renormalise quark masses, we obtain m(ud)((MS) over bar)(2 GeV)= 4.3 +/- 0.4(-0)(+1.1) MeV, and m(s)((MS) over bar)(2 GeV) = 101 +/- 8(-0)(+25) MeV, which are about 15% larger than they would be if renormalised perturbatively. In addition, we show that the above results are compatible wi…
Physics with the KLOE-2 experiment at the upgraded DAFNE
Investigation at a $\phi$--factory can shed light on several debated issues in particle physics. We discuss: i) recent theoretical development and experimental progress in kaon physics relevant for the Standard Model tests in the flavor sector, ii) the sensitivity we can reach in probing CPT and Quantum Mechanics from time evolution of entangled kaon states, iii) the interest for improving on the present measurements of non-leptonic and radiative decays of kaons and eta/eta$^\prime$ mesons, iv) the contribution to understand the nature of light scalar mesons, and v) the opportunity to search for narrow di-lepton resonances suggested by recent models proposing a hidden dark-matter sector. We…
Kaon mixing beyond the SM from N-f=2 tmQCD and model independent constraints from the UTA
We present the first unquenched, continuum limit, lattice QCD results for the matrix elements of the operators describing neutral kaon oscillations in extensions of the Standard Model. Owing to the accuracy of our calculation on Delta S = 2 weak Hamiltonian matrix elements, we are able to provide a refined Unitarity Triangle analysis improving the bounds coming from model independent constraints on New Physics. In our non-perturbative computation we use a combination of N-f = 2 maximally twisted sea quarks and Osterwalder-Seiler valence quarks in order to achieve both O(a)-improvement and continuum-like renormalization properties for the relevant four-fermion operators. The calculation of t…
Light hadron spectrum, renormalization constants and light quark masses with two dynamical fermions
The results of a preliminary partially quenched (N_f=2) study of the light hadron spectrum, renormalization constants and light quark masses are presented. Numerical simulations are carried out with the LL-SSOR preconditioned Hybrid Monte Carlo with two degenerate dynamical fermions, using the plaquette gauge action and the Wilson quark action at beta = 5.8. Finite volume effects have been investigated employing two lattice volumes: 16^3 x 48 and 24^3 x 48. Configurations have been generated at four values of the sea quark mass corresponding to M_{PS}/M_V ~ 0.6 - 0.8.
Operator product expansion and quark condensate from Lattice QCD in coordinate space
We present a lattice QCD determination of the chiral quark condensate based on a new method. We extract the quark condensate from the operator product expansion of the quark propagator at short euclidean distances, where it represents the leading contribution in the chiral limit. From this study we obtain MS( 2 GeV) = -( 265 +/- 5 +/- 22MeV)(3), in good agreement with determinations of this quantity based on different approaches. The simulation is performed by using the O( a)- improved Wilson action at beta = 6.45 on a volume 32(3) x 70 in the quenched approximation.
Flavor physics at large tanβwith a binolike lightest supersymmetric particle
12 pages, 7 figures.-- PACS nrs.: 12.60.Jv; 13.25.Hw; 13.35.-r; 95.35.+d.-- ISI Article Identifier: 000247625300053.-- ArXiv pre-print available at: http://arxiv.org/abs/hep-ph/0703035