The LArIAT liquid argon time projection chamber, placed in a tertiary beam of charged particles at the Fermilab Test Beam Facility, has collected large samples of pions, muons, electrons, protons, and kaons in the momentum range ∼ 300-1400 MeV/c. This paper describes the main aspects of the detector and beamline, and also reports on calibrations performed for the detector and beamline components.

Chiral nanocrystalline cellulose (NCC) free-standing films were prepared through slow evaporation of aqueous suspensions of cellulose nanocrystals in a nematic chiral liquid crystal phase. Mueller matrix (MM) spectroscopic ellipsometry is used to study the polarization and depolarization properties of the chiral films. In the reflection mode, the MM is similar to the matrices reported for the cuticle of some beetles reflecting near circular left-handed polarized light in the visible range. The polarization properties of light transmitted at normal incidence for different polarization states of incident light are discussed. By using a differential decomposition of the MM, the structural circular birefringence and dichroism of a NCC chiral film are evaluated.

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A flexible organic random laser based on poly(9,9-dioctylfluorene) deposited on a surface corrugated polyphthalate-carbonate substrate Appl. Phys. Lett. 98, 253304 (2011) We demonstrate random lasing action in flexible bacterial cellulose (BC) membrane containing a laser-dye and either dielectric or metallic nanoparticles (NPs). The novel random laser system consists of BC nanofibers attached with Rhodamine 6G molecules and having incorporated either silica or silver NPs. The laser action was obtained by excitation of the samples with a 6 ns pulsed laser at 532 nm. Minimum laser threshold of %0.7 mJ/pulse was measured for the samples with silica NPs, whereas a laser threshold of 2.5 mJ/pulse for a system based on silver NPs was obtained. In both cases a linewidth narrowing from %50 to %4 nm was observed. Potential applications in biophotonics and life sciences are discussed for this proof-of-concept device. V C 2014 AIP Publishing LLC. [http://dx

a b s t r a c tNew binuclear lanthanide (III) complexes of general formula [Ln 2 (hcin) 6 (phen) 2 ] (where Ln = Eu 1; Gd 2; Tb 3; hcin = hydrocinnamate anion; phen = 1,10-phenanthroline) were synthesized and fully characterized by elemental analysis, vibrational spectroscopy (infrared and Raman), thermal analysis (TGA/ DTA), CP/MAS 13 C NMR and powder X-ray diffraction. The crystal description based on powder X-ray diffraction data reveals that all compounds are isostructural and that each lanthanide ion is nine coordinated by oxygen and nitrogen atoms to form distorted tricapped trigonal-prismatic coordination polyhedron. The photoluminescence behavior was studied based on the excitation and emission spectra and luminescence decay curves. The emission spectra of Eu(III) and Tb(III) complexes are composed of intense and typical red and green emissions, respectively. Phosphorescence data of Gd(III) complex showed that the triplet states (T 1 ) of ligands have higher energy than the main emitting states of Eu(III) and Tb(III) indicating the possibility of intramolecular energy transfer for these metal ions. To elucidate the energy transfer process in the Eu(III) complex, spectroscopic properties as X k intensity parameters (k = 2 and 4), radiative (A rad ) and nonradiative (A nrad ) decay rates and quantum efficiency (g) of [Eu 2 (hcin) 6 (phen) 2 ] were determined. Such spectroscopic properties were compared with [Eu 2 (hcin) 6 (bpy) 2 ] complex properties recently reported. The high emission quantum efficiency (g = 72%) for Eu(III) complex 1 showed that it is a potential candidate as emitter in photonic systems.