Hadron shower decomposition in the highly granular CALICE analogue hadron calorimeter

The spatial development of hadronic showers in the CALICE scintillator-steel analogue hadron calorimeter is studied using test beam data collected at CERN and FNAL for single positive pions and protons with initial momenta in the range from 10 to 80 GeV/c. Both longitudinal and radial development of hadron showers are parametrised with two-component functions. The parametrisation is fit to test beam data and simulations using the QGSP_BERT and FTFP_BERT physics lists from Geant4 version 9.6. The parameters extracted from data and simulated samples are compared for the two types of hadrons. The response to pions and the ratio of the non-electromagnetic to the electromagnetic calorimeter response, h/e, are estimated using the extrapolation and decomposition of the longitudinal profiles.Comment: 38 pages, 19 figures, 5 tables; author list changed; submitted to JINS

Shower development of particles with momenta from 15 GeV to 150 GeV in the CALICE scintillator-tungsten hadronic calorimeter

We present a study of showers initiated by electrons, pions, kaons, and protons with momenta from 15 GeV to 150 GeV in the highly granular CALICE scintillator-tungsten analogue hadronic calorimeter. The data were recorded at the CERN Super Proton Synchrotron in 2011. The analysis includes measurements of the calorimeter response to each particle type as well as measurements of the energy resolution and studies of the longitudinal and radial shower development for selected particles. The results are compared to Geant4 simulations (version 9.6.p02). In the study of the energy resolution we include previously published data with beam momenta from 1 GeV to 10 GeV recorded at the CERN Proton Synchrotron in 2010.Comment: 35 pages, 21 figures, 8 table

XPS studies of the energy band structure of three Y3+-based fluoride

X-ray photoelectron spectroscopy was applied to the study of the energy band structure of three Y3+-containing insulating crystals: YF3, LiYF4 and KYF4. No features were found in the photoelectron spectra of YF3 and LiYF4 which may be related to the difference in behavior of the scintillation properties of these crystals doped with rare earth ions. Comparison of the photoelectron and luminescence spectra for a KYF4 crystal, which possesses so-called crossluminescence, gave some indication for the existence of lattice relaxation in the vicinity of the long-lived K+ 3p hole

Low-temperature high-resolution VUV spectroscopy of Ce3+ doped LiYF4, LiLuF4 and LuF3 crystals

RadiochFor LiYF4:Ce3+, LiLuF4:Ce3+ and LuF3:Ce3+ crystals UV/visible emission and time-resolved VUV/UV excitation spectra were recorded at liquid helium temperature with spectral resolution of 0.1 nm for excitation spectra and better than 0.3 nm for emission spectra. Well resolved fine structures due to zero-phonon lines were clearly observed in both excitation and emission spectra for LiYF4:Ce3+ and LiLuF4:Ce3+. For LuF3:Ce3+ crystal no fine structure was detected in the spectra even at the highest spectral resolution. Under the host excitation, the fine structure for high-energy emission band of Ce3+ (5d-F-2(5/2)) in LiLuF4:Ce3+ becomes well pronounced because of weaker reabsorption effect, as compared to Ce3+ 4f-5d absorption, due to small penetration depth for exciting radiation. As a result the crystal-field splitting for F-2(7/2) and F-2(5/2) levels of Ce3+ in LiLuF4 crystal was measured. First observation of zero-phonon lines at similar to81,550 and similar to82,900 cm(-1) as well as vibronic side bands due to interconfigurational 4f(14)-4f(13)5d transitions in Lu3+ is reported for excitation spectrum of LiLuF4:Ce3+