Qualification Tests of 474 Photomultiplier Tubes for the Inner Detector of the Double Chooz Experiment

The hemispherical 10" photomultiplier tube (PMT) R7081 from Hamamatsu Photonics K.K. (HPK) is used in various experiments in particle and astroparticle physics. We describe the test and calibration of 474 PMTs for the reactor antineutrino experiment Double Chooz. The unique test setup at Max-Planck-Institut f\"ur Kernphysik Heidelberg (MPIK) allows one to calibrate 30 PMTs simultaneously and to characterize the single photo electron response, transit time spread, linear behaviour and saturation effects, photon detection efficiency and high voltage calibration

Qualification Tests of 474 Photomultiplier Tubes for the Inner Detector of the Double Chooz Experiment

The hemispherical 10" photomultiplier tube (PMT) R7081 from Hamamatsu Photonics K.K. (HPK) is used in various experiments in particle and astroparticle physics. We describe the test and calibration of 474 PMTs for the reactor antineutrino experiment Double Chooz. The unique test setup at Max-Planck-Institut f\"ur Kernphysik Heidelberg (MPIK) allows one to calibrate 30 PMTs simultaneously and to characterize the single photo electron response, transit time spread, linear behaviour and saturation effects, photon detection efficiency and high voltage calibration

Qualification Tests of 474 Photomultiplier Tubes for the Inner Detector of the Double Chooz Experiment

The hemispherical 10" photomultiplier tube (PMT) R7081 from Hamamatsu Photonics K.K. (HPK) is used in various experiments in particle and astroparticle physics. We describe the test and calibration of 474 PMTs for the reactor antineutrino experiment Double Chooz. The unique test setup at Max-Planck-Institut f\"ur Kernphysik Heidelberg (MPIK) allows one to calibrate 30 PMTs simultaneously and to characterize the single photo electron response, transit time spread, linear behaviour and saturation effects, photon detection efficiency and high voltage calibration

Bioinspired Asymmetric Total Synthesis of Emeriones A–C

We report an asymmetric bioinspired total synthesis of the fungal metabolites emeriones A–C via stereoselective late-stage epoxidation or endoperoxidation of two bicyclo[4.2.0]octadiene diastereomers. The central bicyclic scaffold is synthesized in an 8pi/6pi electrocyclization cascade of a stereodefined (E,E,Z,Z,E)-pentaene, which contains the fully assembled and unprotected side chains of the natural products. The pentaene is constructed convergently through Stille cross-coupling of two similarly complex polyenes. The anti-aldol side chain of the emeriones is made using a Paterson-aldol approach, and the epoxide of the dioxobicyclo[3.1.0] side chain is synthesized via ring-closure onto an oxidized para-methoxyphenyl acetal. Our total synthesis has enabled the revision of the structure of emerione C and the synthesis of a “missing” family member, which we hereby call emerione D. DFT calculations indicate the two methyl groups that reside on the cyclobutene ring are critical for the stereochemical outcome of 8pi/6pi electrocyclization

Bioinspired Asymmetric Total Synthesis of Emeriones A–C**

We report asymmetric bioinspired total syntheses of the fungal metabolites emeriones A-C via stereoselective oxidations of two bicyclo[4.2.0]octadiene diastereomers. The central bicyclic scaffolds are prepared in an 8π/6π electrocyclization cascade of a stereodefined pentaene, which contains the fully assembled side chains of the emeriones. The anti-aldol side chain is made using a Paterson-aldol addition, and the epoxide of the dioxabicyclo[3.1.0]hexane side chain via ring-closure onto an oxidized acetal. Our work has enabled the structural revision of emerione C, and resulted in the synthesis of a "missing" family member, which we call emerione D. DFT calculations identified two methyl groups that govern torquoselectivity in the 8π/6π cascade