A new measurement of direct CP violation in two pion decays of the neutral kaon

The NA48 experiment at CERN has performed a new measurement of direct CP violation, based on data taken in 1997 by simultaneously collecting K_L and K_S decays into pi0pi0 and pi+pi-. The result for the CP violating parameter Re(epsilon'/epsilon) is (18.5 +/- 4.5(stat)} +/- 5.8 (syst))x10^{-4}.Comment: 18 pages, 6 figure

Direct search for light gluinos

We present the results for a direct search for light gluinos through the appearance of $\eta\rightarrow 3\pi^{0}$ with high transverse momentum in the vacuum tank of the NA48 experiment at CERN. We find one event within a lifetime range of $10^{-9}-10^{-3}$s and another one between $10^{-10}-10^{-9}$s. Both events are consistent with the expected background from neutrons in the beam, produced by 450 GeV protons impinging on the Be targets, which interact with the residual air in the tank. From these data we give limits on the production of the hypothetical $g\widetilde{g}$ bound state, the $R^0$ hadron, and its $R^0\rightarrow\eta\widetilde{\gamma}$ decay in the $R^0$ mass range between 1 and 5~GeV

A new measurement of direct CP violation in two pion decays of the neutral kaon

The NA48 experiment at CERN has performed a new measurement of direct CP violation, based on data taken in 1997 by simultaneously collecting KL and KS decays into pi0 pi0 and pi+ pi-. The result for the CP violating parameter Re(epsilon'/epsilon) is (18.5 +- 4.5(stat.) +- 5.8(syst.)) x 10^-4

CPMG measurements and ultrafast imaging in human lungs with hyperpolarized helium-3 at low field (0.1 T).

International audienceThis work reports the use of single-shot spin echo sequences to achieve in vivo diffusion gas measurements and ultrafast imaging of human lungs, in vivo, with hyperpolarized He-3 at 0.1 T. The observed transverse relaxation time of He-3 lasted up to 10 s, which made it possible to use long Carr-Purcelf-Meiboom-Gill echo trains. Preliminary NMR studies showed that the resolution of lung images acquired with hyperpolarized He-3 and single-shot sequences is limited to about 6 mm because of the diffusion of the gas in applied field gradients. Ultrafast images of human lungs in normal subjects, achieved in less than 0.4 s with the equivalent of only 130 mu mol of fully polarized He-3, are presented. Comparison with other studies shows that there is no SNR penalty by using low fields in the hyperpolarized case. Advantage was taken of the self diffusion-weighting of the rapid acquisition with relaxation enhancement (RARE) sequence to acquire apparent diffusion coefficient (ADC) images of the lungs. Time scales of seconds could be explored for the first time because there is no hindrance from T-2(star) as with the usual approaches. At 0.1 T, 180 degrees RF pulses can be repeated every 10 ms without exceeding specific absorption rate limits, which would not be the case for higher fields. Moreover, at low field, susceptibility-induced phenomena are expected to be milder. This supports the idea that low-field imagers can be used for hyperpolarized noble gas MRI of lungs and may be preferred for ADC measurements. Magn Reson Med 47:75-81, 2002. (C) 2002 Wiley-Liss, Inc

Measurement of the decay rate and form factor parameter alpha(K*) in the decay KL -> e+ e- gamma

The decay rate of the neutral K meson KL -> e+ e- gamma has been measured with the NA48 detector at the CERN SPS. A total of 6864 events has been observed with an estimated background of 10 events. The branching ratio is Gamma(KL->e+e-gamma)/Gamma(KL->all) = (1.06 +- 0.02(stat) +- 0.02(sys) +- 0.04(calc))x 10^-5. The parameter alpha(K*) describing the relative strength of the two contributing amplitudes to this decay through intermediate pseudoscalar or vector mesons was measured to be alpha(K*) = 0.36 +- 0.06(stat) +- 0.02(sys)

Measurement of the decay rate and form factor parameter αK∗\alpha_{K^{*}} in the decay KL→e+e−γK_{L} \rightarrow e^{+}e^{-}\gamma

The decay rate of the neutral K meson $\mathrm{K_{L} \rightarrow e^{+}e^{-}\gamma}$ has been measured with the NA48 detector at the CERN SPS. A total of 6864 events has been observed with an estimated background of 10 events. The branching ratio is $\mathrm{\Gamma(K_{L} \rightarrow e^{+}e^{-}\gamma)/\Gamma(K_{L} rightarrow all) = (1.06 \pm 0.02_{stat.} \pm 0.02_{sys.} \pm 0.04_{calc.})\times 10^{-5}}$. The parameter describing the relative strength of the two contributing amplitudes to this decay through $\mathrm{\alpha_{K^{*}}}$ intermediate seudoscalar or vector mesons, was measured to be $\mathrm{\alpha_{K^{*}} = -0.36 \pm 0.06_{stat.} \pm 0.02_{sys.}}

Direct search for light gluinos RID A-4071-2012

We present the results for a direct search for light gluinos through the appearance of eta --> 3 pi(0) with high transverse momentum in the vacuum tank of the NA48 experiment at CERN. We find one event within a lifetime range of 10(-9)-10(-3) s and another one between 10(-10)-10(-9) s. Both events are consistent with the expected background from neutrons in the beam, produced by 450 GeV protons impinging on the Be targets, which interact with the residual air in the tank. From these data we give limits on the production of the hypothetical g (g) over tilde bound state, the R-0 hadron, and its R-0 --> eta decay in the R-0 mass range between 1 and 5 GeV. (C) 1999 Elsevier Science B.V. All rights reserved

Measurement of the decay rate and form factor parameter alpha(K*) in the decay K-L -> e(+)e(-)gamma

The decay rate of the neutral K meson K-L --> e(+)e(-)gamma has been measured with the NA48 detector at the CERN SPS. A total of 6864 events has been observed with an estimated background of 10 events. The branching ratio is Gamma(K-L --> e(+)e(-)gamma)/Gamma(K-L --> all) = (1.06 +/- 0.02(stat) +/- 0.02(sys) +/- 0.04(calc)) X 10(-5). The parameter alpha(K*) describing the relative strength of the two contributing amplitudes to this decay through intermediate pseudoscalar or vector mesons was measured to be alpha(K*) = -0.36 +/- 0.06(stat) +/- 0.02(sys). (C) 1999 Published by Elsevier Science B.V. All rights reserved