The T2K near detector data acquisition systems
IEEE Transactions on Nuclear Science 58:4 PART 1 (2011) 1800-1806
Abstract:
T2K is a second generation long-baseline experiment in Japan, designed to perform precision studies of neutrino oscillations. A neutrino beam originating at the J-PARC facility is sampled by two near detectors, approximately 280 m distant from the source and directed towards the Kamioka underground facility, 295 km distant, where the Super-Kamiokande water Cerenkov detector is situated. Both the on-axis (INGRID) and off-axis (ND280) near detectors employ the MIDAS framework for their data acquisition systems. Events are selected via a flexible hardware trigger, which allows mixed operating modes incorporating beam spill, cosmic and calibration triggers. Data are acquired from the front-end electronics over optical Gigabit Ethernet links by custom MIDAS front-end applications distributed over a cluster of Linux computers. Event fragments from all sub-detectors are merged and logged on a central backend processor and then copied to remote storage for long-term archival. The system is also designed to allow flexible partitioning of sub-detectors for standalone diagnostics and calibration. We present the design of the DAQ system and report on experience gathered during early operation of the near detectors. © 2006 IEEE.Improved search for muon-neutrino to electron-neutrino oscillations in MINOS
(2011)
Limits on anomalous trilinear gauge couplings in Zγ events from pp̄ collisions at √s=1.96TeV
Physical Review Letters 107:5 (2011)
Abstract:
Using Zγ candidate events collected by the CDF detector at the Tevatron Collider, we search for potential anomalous (non-standard-model) couplings between the Z boson and the photon. Zγ couplings vanish at tree level and are heavily suppressed at higher orders; hence any evidence of couplings indicates new physics. Measurements are performed using data corresponding to an integrated luminosity of 4.9fb-1 in the Z→νν̄ decay channel and 5.1fb-1 in the Z→l +l- (l=μ, e) decay channels. The combination of these measurements provides the most stringent limits to date on Zγ trilinear gauge couplings. Using an energy scale of Λ=1.5TeV to allow for a direct comparison with previous measurements, we find limits on the CP-conserving parameters that describe Zγ couplings to be |h3γ,Z|<0.022 and |h4γ,Z|<0.0009. These results are consistent with standard model predictions. © 2011 American Physical Society.Search for New Dielectron Resonances and Randall-Sundrum Gravitons at the Collider Detector at Fermilab
Physical Review Letters 107:5 (2011)
Abstract:
A search for new dielectron-mass resonances using data recorded by the CDF II detector and corresponding to an integrated luminosity of 5.7fb-1 is presented. No significant excess over the expected standard model prediction is observed. In this data set, an event with the highest dielectron mass ever observed (960GeV/c2) was recorded. The results are interpreted in the Randall-Sundrum (RS) model. Combined with the 5.4fb-1 diphoton analysis, the RS-graviton lower-mass limit for the coupling k/M ̄Pl=0.1 is 1058GeV/c2, making it the strongest limit to date. © 2011 American Physical Society.First search for multijet resonances in √s=1.96TeV pp̄ collisions
Physical Review Letters 107:4 (2011)