Recent QCD results from the NA48/2 experiment Anzivino, Giuseppina; Anzivino, G.; Arcidiacono, R. ...
Nuclear and particle physics proceedings,
07/2018, Volume:
300-302
Journal Article
Peer reviewed
The NA48/2 experiment collected data in 2003 and 2004 with the main purpose to study direct CP violation in charged kaons decaying in three pions. Thanks to the huge statistics collected, other ...studies are also possible. In this paper two recent results, in the framework of QCD studies, are reported: the measurement of the K± → π0e±ν Form Factors and the first observation of the rare decay K± → π±π0e+e−.
A sample of 1.69×107 fully reconstructed π0→γe+e− decay candidates collected by the NA48/2 experiment at CERN in 2003–2004 is analyzed to search for the dark photon (A′) production in the π0→γA′ ...decay followed by the prompt A′→e+e− decay. No signal is observed, and an exclusion region in the plane of the dark photon mass mA′ and mixing parameter ε2 is established. The obtained upper limits on ε2 are more stringent than the previous limits in the mass range 9 MeV/c2<mA′<70 MeV/c2. The NA48/2 sensitivity to the dark photon production in the K±→π±A′ decay is also evaluated.
The NA48/2 experiment at CERN collected two data samples with minimum bias trigger conditions in 2003 and 2004. A measurement of the rate and dynamic properties of the rare decay K plus or minus ...arrow right pi plus or minus gamma gamma K plus or minus arrow right pi plus or minus gamma gamma from these data sets based on 149 decay candidates with an estimated background of 15.5 plus or minus 0.715.5 plus or minus 0.7 events is reported. The model-independent branching ratio in the kinematic range z=(m gamma gamma /mK)2>0.2z=(m gamma gamma /mK)2>0.2 is measured to be BMI(z>0.2)=(0.877 plus or minus 0.089)10-6BMI(z>0.2)=(0.877 plus or minus 0.089)10-6, and the branching ratio in the full kinematic range assuming a particular Chiral Perturbation Theory description to be B(K pi gamma gamma )=(0.910 plus or minus 0.075)10-6B(K pi gamma gamma )=(0.910 plus or minus 0.075)10-6.
APE computers—past, present and future Bodin, F.; Boucaud, Ph; Cabibbo, N. ...
Computer physics communications,
08/2002, Volume:
147, Issue:
1
Journal Article, Conference Proceeding
Peer reviewed
Open access
APE is a family of supercomputers architecturally optimized for the numerical simulation of quantum field theories. Current generation APE systems (APEmille) have been commissioned at several ...European sites. When all planned systems are installed, later this year, a total peak processing power of about 2 TFlops will be available. A new generation system, apeNEXT, is under development. It adds several new features to the established APE architecture. Performance will be boosted towards the 10 Tflops range.
NA48/2 results contributing to ChPT testing are presented. A sample of 1663 events of the rare decay $ K^ \pm \to \mu ^ \pm ve^ + e^ - $ has been selected with a minimum
e
+
e
−
effective mass of 140 ...MeV. The measured model independent decay rate is in agreement with ChPT predictions. The branching ratio of the $ K^ \pm \to \mu ^ \pm ve^ + e^ - $ decay, never observed so far, has been obtained from a sample of about 5000 candidates with less than 6% background, also in agreement with ChPT predictions. In addition, a most precise measurement of the charged kaon semileptonic formfactors has been obtained from 4.4 million
K
e3
and 2.3 million
K
µ3
events collected in 2004.
The NA48/2 experiment at CERN collected two data samples with minimum bias trigger conditions in 2003 and 2004. A measurement of the rate and dynamic properties of the rare decay K±→π±γγ from these ...data sets based on 149 decay candidates with an estimated background of 15.5±0.7 events is reported. The model-independent branching ratio in the kinematic range z=(mγγ/mK)2>0.2 is measured to be BMI(z>0.2)=(0.877±0.089)×10−6, and the branching ratio in the full kinematic range assuming a particular Chiral Perturbation Theory description to be B(Kπγγ)=(0.910±0.075)×10−6.
Effects of new physics in flavor could be found both in Flavor Changing Neutral Current (FCNC) processes and in Lepton Flavor Violation (LFV) modes. The former offer the possibility to deeply test ...the standard model in a clean environment, while the latter are sensitive to contribution from several models beyond the standard model. In the Kaon sector both FCNC and LFV will be investigated in the NA62 experiment. In addition the kaons sector is an ideal place where to look for new particles and tiny effects, in the region of hundreds of MeV/c2. In this paper prospects for exotic searches in NA62 will be presented, together with recent results from NA48/2 and NA62-RK on LFV kaon decays modes.
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