Light at the end of the tunnel? Femtosecond pulses excite short-wavelength lasers
Optics and Photonics News 8:4 (1997) 21-25
Abstract:
Hooker explores current work in the XUV and soft x-ray spectral region aimed at achieving "table-top" short-wavelength lasers.The ZEUS leading proton spectrometer and its use in the measurement of elastic ρ0 photoproduction at HERA
Zeitschrift fur Physik C-Particles and Fields 73:2 (1997) 253-268
Abstract:
The differential cross section dσ/dt for elastic ρ0 photoproduction, γp → ρ0ρ (ρ0 → π+π-), has been measured in ep interactions at HERA. The squared four-momentum exchanged at the proton vertex, t, has been determined directly by measuring the momentum of the scattered proton using the ZEUS Leading Proton Spectrometer (LPS), a large scale system of silicon micro-strip detectors operating close to the HERA proton beam. The LPS allows the measurement of the momentum of high energy protons scattered at small angles with accuracies of 0.4% for the longitudinal momentum and 5 MeV for the transverse momentum. Photoproduction of ρ0 mesons has been investigated in the interval 0.073 < |t| < 0.40 GeV2, for photon virtualities Q2 < 1 GeV2 and photon-proton centre-of-mass energies W between 50 and 100 GeV. In the measured range, the t distribution exhibits an exponential shape with a slope parameter b = 9.8 ± 0.8 (stat.) ± 1.1 (syst.) GeV-2. The use of the LPS eliminates the contamination from events with diffractive dissociation of the proton into low mass states. © Springler-Verlag 1997.Vacuum ultraviolet gain measurements in optically pumped LiYF4 :Nd3+
Applied Physics B: Lasers and Optics 64:3 (1997) 293-300
Abstract:
We present measurements of the net-induced gain on the 5d-4f transition at 186 nm in LiYF4:Nd3+ optically pumped by radiation from a molecular fluorine laser. It is found that for LiYF4: Nd3+ one of a series of potential continuously tunable VUV lasers, relatively strong excited-state absorption results in net-induced loss. The prospects for VUV laser operation being realised in other rare-earth-doped fluorides is discussed.Comparison of ZEUS data with standard model predictions for e(+)p->e(+)X scattering at high x and Q(2)
ZEITSCHRIFT FUR PHYSIK C-PARTICLES AND FIELDS 74:2 (1997) 207-220
D* production in deep inelastic scattering at HERA
PHYSICS LETTERS B 407:3-4 (1997) 402-418