The high precision measurement of the hyperfine splitting of the muonic-hydrogen atom ground state with pulsed and intense muon beam requires careful technological choices both in the construction of a gas target and of the detectors. In June 2014, the pressurized gas target of the FAMU experiment was exposed to the low energy pulsed muon beam at the RIKEN RAL muon facility. The objectives of the test were the characterization of the target, the hodoscope and the X-ray detectors.The apparatus consisted of a beam hodoscope and X-rays detectors made with high purity Germanium and Lanthanum Bromide crystals. In this paper the experimental setup is described and the results of the detector characterization are presented. * Andrea.Vacchi@ts.infn.it

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This paper continues the debate concerning the availability of Universal Grammar (UG) to adult L2 acquirers. Specifically, an analysis of native (prodrop) Romance speakers' acquisition of negative placement in L2 German is provided. Contrary to Clahsen (1987; 1988a) and Clahsen and Muysken (1988), we argue that a UG-based analysis for the three stages of NEGplacement is not only possible but in fact provides independent support for UG-based analyses of the developmental sequence found in L1 Romance, L2 German Verb placement (duPlessis et al, 1987; Schwartz and Tomaselli, 1988). In particular, by combining (1) aspects of the L 1 grammar with (2) the independently needed changes in parameter values (characterizing principal differences between the L1 and L2 grammars), we arrive at a non- ad hoc account. We also show how the resolution of additional problems concerning the data of this same set of L2 acquirers naturally follows from the analysis argued for. Finally, some discussion comparing the two UG-based analyses of the verb-placement data (duPlessis et al.'s and Schwartz and Tomaselli's) is included.

We show that the large effective optical nonlinearity, which is produced by cascaded second-order processes, allows us to accomplish the frequency conversion of a signal pulse with a pump pulse of moderate intensity. In a 1 cm long β-barium borate crystal, the cascaded effect enhances by 5 orders of magnitude the efficiency of the frequency mixing process. The enhancement is larger than 104 even in non-phase-matched condition for the intermediate second-harmonic field, when the imaginary part of the induced nonlinear susceptibility is negligible.

We report on a high-energy solid-state laser based on a master-oscillator power-amplifier system seeded by a 5-GHz repetition-rate mode-locked oscillator, aimed at the excitation of the dynamic Casimir effect by optically modulating a microwave resonator. Solid-state amplifiers provide up to 250 mJ at 1064 nm in a 500-ns (macro-)pulse envelope containing 12-ps (micro-)pulses, with a macro/micropulse format and energy resembling that of near-infrared free-electron lasers. Efficient second-harmonic conversion allowed synchronous pumping of an optical parametric oscillator, obtaining up to 40 mJ in the range 750-850 nm.