The CDF Run IIa silicon detector and its upgrade Run IIb Issever, C.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
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The CDF RunIIa silicon detector has now made the transition from commissioning to data taking. The current state of the CDF RunIIa silicon detector's online and of fline tracking algorithms, the ...performance of Layer 00, and the status of the Run IIb silicon upgrade project are presented in this article.
An improved weighting algorithm applied to hadron showers has been developed for a fine grained LAr calorimeter. In contrast to standard weighting procedures, the new algorithm allows to reconstruct ...the total energy as well as the spatial energy deposition on the level of individual calorimeter cells. The linearity and the energy resolution of the pion signal in the momentum interval
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studied in this analysis are considerably improved in comparison to the standard weighting algorithm as practiced presently by the H1 collaboration. Moreover the energy spectra reconstructed with the new method follow in a broad interval a Gaussian distribution and have less pronounced tails.
We present the report of the hadronic working group of the BOOST2010 workshop held at the University of Oxford in June 2010. The first part contains a review of the potential of hadronic decays of ...highly boosted particles as an aid for discovery at the LHC and a discussion of the status of tools developed to meet the challenge of reconstructing and isolating these topologies. In the second part, we present new results comparing the performance of jet grooming techniques and top tagging algorithms on a common set of benchmark channels. We also study the sensitivity of jet substructure observables to the uncertainties in Monte Carlo predictions.
The DECAL sensor is a depleted monolithic active pixel sensor (DMAPS) being developed to explore technological solutions for digital electromagnetic calorimeters. For this application, the number of ...pixels above threshold is used to estimate the shower energy and therefore the pixel size is required to be sufficiently small to avoid hit saturation. The DECAL and DECAL Fully Depleted (FD) sensors have been designed and fabricated in the TowerJazz 180 nm CMOS standard and modified imaging processes, respectively. The latter uses modifications to the implant configuration that improve charge collection and radiation hardness, including to the levels required for barrel ECAL regions of FCC-hh (few 1015 neq/cm2). Both DECAL variants feature a matrix of 64 × 64 pixels with a pitch of 55μm, read out every 25 ns. For DECAL FD, the logic has been modified to extend the in-pixel comparator threshold trim range from five to six bits, with the sixth bit used to de-activate the comparator. Characterisation results for the DECAL FD, including the pixel equalisation matrix, threshold scans testing under monochromatic X-rays and 90Sr source, are presented.
We study the radiation hardness of the Vertical Cavity Surface Emitting Laser diodes (VCSELs) and the epitaxial silicon PIN diodes that will be used for the Atlas SemiConductor Tracker at the CERN ...Large Hadron Collider. The tests were conducted with 200
MeV protons to a fluence of
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. The radiation damage of the VCSELs and PINs and the annealing characteristics are presented.
The Collider Detector at Fermilab (CDF) pursues a broad physics program at Fermilab's Tevatron collider. Between Run II commissioning in early 2001 and the end of operations in September 2011, the ...Tevatron delivered 12fb−1 of integrated luminosity of pp¯ collisions at s=1.96TeV. The physics at CDF includes precise measurements of the masses of the top quark and W boson, measurement of CP violation and Bs mixing, and searches for Higgs bosons and new physics signatures, all of which require heavy flavor tagging with large charged particle tracking acceptance. To realize these goals, in 2001 CDF installed eight layers of silicon microstrip detectors around its interaction region. These detectors were designed for 2–5 years of operation, radiation doses up to 2Mrad (0.02Gy), and were expected to be replaced in 2004. The sensors were not replaced, and the Tevatron run was extended for several years beyond its design, exposing the sensors and electronics to much higher radiation doses than anticipated. In this paper we describe the operational challenges encountered over the past 10 years of running the CDF silicon detectors, the preventive measures undertaken, and the improvements made along the way to ensure their optimal performance for collecting high quality physics data. In addition, we describe the quantities and methods used to monitor radiation damage in the sensors for optimal performance and summarize the detector performance quantities important to CDF's physics program, including vertex resolution, heavy flavor tagging, and silicon vertex trigger performance.
•We have operated the CDF II silicon detector system well beyond its design lifetime.•We describe design of each component, its performance parameters and resource needs.•A history of operational experience and mitigation of encountered problems is given.•Novel methods were found to mitigate wirebond resonance and cooling system corrosion.•Radiation aging effects on silicon sensors from a decade long exposure are presented.