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An analog hadron calorimeter (AHCAL) prototype of 5.3 nuclear interaction lengths thickness has been constructed by members of the CALICE Collaboration. The AHCAL prototype consists of a 38-layer sandwich structure of steel plates and highly-segmented scintillator tiles that are read out by wavelength-shifting fibers coupled to SiPMs. The signal is amplified and shaped with a custom-designed ASIC. A calibration/monitoring system based on LED light was developed to monitor the SiPM gain and to measure the full SiPM response curve in order to correct for non-linearity. Ultimately, the physics goals are the study of hadron shower shapes and testing the concept of particle flow. The technical goal consists of measuring the performance and reliability of 7608 SiPMs. The AHCAL was commissioned in test beams at DESY and CERN. The entire prototype was completed in 2007 and recorded hadron showers, electron showers and muons at different energies and incident angles in test beams at CERN and Fermilab.

The CALICE collaboration is studying the design of high performance electromagnetic and hadronic calorimeters for future International Linear Collider detectors. For the hadronic calorimeter, one option is a highly granular sampling calorimeter with steel as absorber and scintillator layers as active material. High granularity is obtained by segmenting the scintillator into small tiles individually read out via silicon photo-multipliers (SiPM). A prototype has been built, consisting of thirty-eight sensitive layers, segmented into about eight thousand channels. In 2007 the prototype was exposed to positrons and hadrons using the CERN SPS beam, covering a wide range of beam energies and angles of incidence. The challenge of cell equalization and calibration of such a large number of channels is best validated using electromagnetic processes. The response of the prototype steel-scintillator calorimeter, including linearity and uniformity, to electrons is investigated and described.

A highly granular electromagnetic calorimeter with scintillator strip readout is being developed for future linear collider experiments. A prototype of 21.5 X 0 depth and 180 × 180 mm 2 transverse dimensions was constructed, consisting of 2160 individually read out 10 ×45 × 3 mm 3 scintillator strips. This prototype was tested using electrons of 2 -32 GeV at the Fermilab Test Beam Facility in 2009. Deviations from linear energy response were less than 1.1%, and the intrinsic energy resolution was determined to be (12.5 ± 0.1(stat.) ± 0.4(syst.))%/ E[ GeV] ⊕ (1.2 ± 0.1(stat.) +0.6 −0.7 (syst.))%, where the uncertainties correspond to statistical and systematic sources, respectively.

The present study quantitatively measured, via UV absorption spectroscopy, the molecular orientation of the drug chlorpromazine (CPZ) after spontaneous penetration into the gel phase of a phospholipid membrane. An L-R-dipalmitoylphosphatidylcholine (DPPC) Langmuir (L) film (a monolayer on an aqueous solution) was doped with CPZ and transferred onto a quartz substrate to form a Langmuir-Blodgett (LB) film. The transmission spectrum of the LB film was measured using a normal incident, nonpolarized UV beam. To calculate the theoretical absorbances, the extinction coefficients of oriented CPZ molecules in the DPPC LB film were deduced from the molar extinction coefficients of nonoriented, dispersed CPZ molecules in an aqueous solution. The anisotropic extinction coefficient of CPZ was determined with the uniaxial refractive index ellipsoid model as a function of orientation angle, using the extinction coefficient of CPZ in the bulk state. By comparing the theoretical absorbances with observed absorbances, the orientation angles from the surface normal of the LB film of transition moments along the molecular short and long axes were determined to be 17°and 85°, respectively. The results of the present study indicate that CPZ molecules penetrate deep into the DPPC membranes and that the molecular orientation of CPZ is determined by the surrounding DPPC molecules.