Three-dimensional image reconstruction in medical applications (PET or X-ray CT) utilizes sophisticated filter algorithms to linear trajectories of coincident photon pairs or x-rays. The goal is to ...reconstruct an image of an emitter density distribution. In a similar manner, tracks in particle physics originate from vertices that need to be distinguished from background track combinations. In this study it is investigated if vertex reconstruction in high energy proton collisions may benefit from medical imaging methods. A new method of vertex finding, the Medical Imaging Vertexer (MIV), is presented based on a three-dimensional filtered backprojection algorithm. It is compared to the open-source RAVE vertexing package. The performance of the vertex finding algorithms is evaluated as a function of instantaneous luminosity using simulated LHC collisions. Tracks in these collisions are described by a simplified detector model which is inspired by the tracking performance of the LHC experiments. At high luminosities (25 pileup vertices and more), the medical imaging approach finds vertices with a higher efficiency and purity than the RAVE “Adaptive Vertex Reconstructor” algorithm. It is also much faster if more than 25 vertices are to be reconstructed because the amount of CPU time rises linearly with the number of tracks whereas it rises quadratically for the adaptive vertex fitter AVR.
The power supply system of the CLEO III silicon detector von Toerne, E; Burns, J; Duboscq, J ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2002, Letnik:
481, Številka:
1
Journal Article
Recenzirano
The CLEO III detector has recently commenced data taking at the Cornell Electron Storage Ring (CESR). One important component of this detector is a four layer double-sided silicon tracker with 93% ...solid angle coverage. This detector ranges in size and number of readout channels between the LEP and LHC silicon detectors. In order to reach the detector performance goals of signal-to-noise ratios greater than
15
:
1
low noise front-end electronics together with highly regulated low noise power supplies were used. In this paper, we describe the low-noise power supply system and associated monitoring and safety features used by the CLEO III silicon tracker.
The CLEO III silicon vertex detector Kass, R.; Alam, M.S.; Alexander, J.P. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2003, Letnik:
501, Številka:
1
Journal Article
Recenzirano
The design and operation of the CLEO III silicon vertex detector is described in this report. This detector consists of four layers of double-sided silicon wafers covering 93% of the solid angle. ...After initially meeting its signal-to-noise and spatial resolution design goals, the
r−
φ side efficiency of layers 1 and 2 decreased dramatically due to radiation-induced sensor effects.
Status of the CLEO III silicon tracker von Toerne, E.; Alam, M.S.; Alexander, J.P. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2003, Letnik:
511, Številka:
1
Journal Article
Recenzirano
The CLEO-III silicon vertex detector is a 4-layer device with double-sided silicon sensors arranged in a barrel design, covering 93% of the solid angle. After initially meeting its design goals of ...signal-to-noise performance and spatial resolution, the signal efficiency deteriorated on the rφ sensor side in the two innermost layers due to radiation induced sensor effects. Operation of the two outermost layers and the
z-coordinate readout in all layers is stable.
Design and initial performance of the CLEO III silicon tracker von Toerne, E; Alam, M.S; Alexander, J.P ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2001, Letnik:
473, Številka:
1
Journal Article
Recenzirano
CLEO III is the new experimental phase of the CLEO experiment at the CESR accelerator. Both the accelerator and the detector have recently been upgraded. A new charged particle tracking system with ...the addition of a ring imaging Cherenkov particle identification system has been installed. A major part of the tracking system upgrade was the construction of a new four-layer double-sided silicon tracker with 93% solid angle coverage and new readout electronics. The CLEO III upgrade was completed in February 2000 with the installation of the silicon detector. CLEO III has finished the commissioning phase and is now taking data. The design of the detector and first performance results are presented here.
DEPFET, a monolithic active pixel sensor for the ILC Velthuis, J.J.; Kohrs, R.; Mathes, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2007, Letnik:
579, Številka:
2
Journal Article
Recenzirano
In a DEPleted Field Effect Transistor (DEPFET) sensor a MOSFET is integrated on a sidewards depleted p-on-n silicon detector, thereby combining the advantages of a fully depleted silicon sensor with ...in-pixel amplification. A 450
μm thick DEPFET was tested in a testbeam. The
S/
N was found to be larger than 110. The position resolution is better than 5
μm. At a seed cut of 7
σ, the efficiency and purity are both close to 100%. In the readout chip a zero-suppression capability is implemented. The functionality was demonstrated using a radio-active source. The predicted impact parameter resolution of a 50
μm thick DEPFET vertex detector, is much better than required for the International Linear Collider (ILC).
It has been found that Figure 30 shows the 68% and 99% confidence-level contours for the W boson and top quark mass measurements, instead of the 68% and 95% confidence-level contours, as stated in ...the legend.
This paper presents a direct measurement of the decay width of the top quark using
events in the lepton+jets final state. The data sample was collected by the ATLAS detector at the LHC in ...proton-proton collisions at a centre-of-mass energy of 8 TeV and corresponds to an integrated luminosity of 20.2 fb
. The decay width of the top quark is measured using a template fit to distributions of kinematic observables associated with the hadronically and semileptonically decaying top quarks. The result,
for a top-quark mass of 172.5 GeV, is consistent with the prediction of the Standard Model.
A measurement of the mass of the W boson is presented based on proton-proton collision data recorded in 2011 at a centre-of-mass energy of 7 TeV with the ATLAS detector at the LHC, and corresponding ...to Formula omitted of integrated luminosity. The selected data sample consists of Formula omitted candidates in the Formula omitted channel and Formula omitted candidates in the Formula omitted channel. The W-boson mass is obtained from template fits to the reconstructed distributions of the charged lepton transverse momentum and of the W boson transverse mass in the electron and muon decay channels, yielding mW=80370±7(stat.)±11(exp. syst.)±14(mod. syst.)MeV=80370±19MeV,where the first uncertainty is statistical, the second corresponds to the experimental systematic uncertainty, and the third to the physics-modelling systematic uncertainty. A measurement of the mass difference between the Formula omitted and Formula omitted bosons yields Formula omitted MeV.
For the detection of secondary vertices of long lived particles containing bottom and charm quarks at the International Linear Collider (ILC), a DEPFET pixel detector is one of the technologically ...favored options. In a DEPFET sensor a MOSFET pixel detector is integrated on a sidewards depleted silicon bulk sensor, thus combining the advantages of a fully depleted silicon sensor with in-pixel amplification. DEPFET pixel matrices have been characterized in a high energy particle beam. Since the DEPFET is a very high precision device, given its large S/N (> 100) and small pixel size (36 × 22 ¿m 2 ), a DEPFET based pixel telescope consisting of 5 DEPFETs has been developed. The uncertainty on the predicted position for a device under test (DUT) positioned inside the telescope was found to be 1.4 ¿m with the existing device, due to the limited performance of two of the five DEPFET planes. A DEPFET telescope built of 5 modules equivalent to the best plane presented here, would have a track extrapolation error as low as 0.65 ¿m at the DUT plane.