Inclusive jet, dijet and trijet differential cross sections are measured in neutral current deep-inelastic scattering for exchanged boson virtualities
150
<
Q
2
<
15
000
GeV
2
using the H1 detector ...at HERA. The data were taken in the years 2003 to 2007 and correspond to an integrated luminosity of
351
pb
-
1
. Double differential Jet cross sections are obtained using a regularised unfolding procedure. They are presented as a function of
Q
2
and the transverse momentum of the jet,
P
T
jet
, and as a function of
Q
2
and the proton’s longitudinal momentum fraction,
ξ
, carried by the parton participating in the hard interaction. In addition normalised double differential jet cross sections are measured as the ratio of the jet cross sections to the inclusive neutral current cross sections in the respective
Q
2
bins of the jet measurements. Compared to earlier work, the measurements benefit from an improved reconstruction and calibration of the hadronic final state. The cross sections are compared to perturbative QCD calculations in next-to-leading order and are used to determine the running coupling and the value of the strong coupling constant as
α
s
(
M
Z
)
=
0.1165
(
8
)
exp
(
38
)
pdf
,
theo
.
Full text
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Readout chip for Column Parallel CCD, CPR2A Havranek, M.; Murray, P.; Stefanov, K. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2009, Volume:
607, Issue:
3
Journal Article
Peer reviewed
The LCFI Collaboration is developing the sensors, readout electronics and mechanical support structures for the vertex detector (VXD) of the International Linear Collider (ILC), as well as studying ...the physics performance that the VXD will achieve. Since the VXD must provide excellent spatial resolution, the sensors must have very low mass and their power consumption must be small to ensure that the sensors themselves cause as little multiple scattering as possible and that gas cooling can be used to operate them at temperatures of about −40
C. High-speed readout is also needed to ensure that the occupancy due to the pair production background at the ILC is kept below the 1% level. In order to satisfy these strict requirements, Column Parallel CCDs (CPCCDs) and Column Parallel Readout chips (CPRs) have been developed. The readout chips must be able to operate synchronously with the CPCCDs and ensure fast signal processing with low noise and data compression. The design and performance of the latest version of the readout chip, the CPR2A, are described here.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This work will report on the characterisation of a new active pixel sensor, Vanilla. The Vanilla comprises of 512×512 (25μm
2) pixels. The sensor has a 12
bit digital output for full-frame mode, ...although it can also be readout in analogue mode, whereby it can also be read in a fully programmable region-of-interest (ROI) mode. In full frame, the sensor can operate at a readout rate of more than 100
frames per second (fps), while in ROI mode, the speed depends on the size, shape and number of ROIs. For example, an ROI of 6×6 pixels can be read at 20,000
fps in analogue mode.
Using photon transfer curve (PTC) measurements allowed for the calculation of the read noise, shot noise, full-well capacity and camera gain constant of the sensor. Spectral response measurements detailed the quantum efficiency (QE) of the detector through the UV and visible region. Analysis of the ROI readout mode was also performed. Such measurements suggest that the Vanilla APS (active pixel sensor) will be suitable for a wide range of applications including particle physics and medical imaging.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
39.
Planar transformers for column parallel CCD clock drive Hawes, B.; Cussans, D.; Damerell, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2009, Volume:
609, Issue:
2
Journal Article
Peer reviewed
The LCFI Collaboration is developing the sensors, readout electronics and mechanical support structures for the Vertex Detector (VXD) of the International Linear Collider (ILC). High-speed readout is ...needed to ensure that the occupancy due to the pair production background at the ILC is kept below 1% level. In order to satisfy this requirement, Column Parallel CCDs (CPCCDs) and Column Parallel Readout chips (CPRs) have been developed. The CPCCD has to operate at a clock frequency of 50
MHz, which represents a difficult technical challenge due to the relatively large sensor capacitance. The design and performance of planar transformers, which can be used to provide the required 20
A clock current, are described.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The H1 detector at the electron proton collider HERA at DESY in Hamburg is designed to study the products of collisions of 27.5 GeV electrons with 820 GeV protons. One of the features of the detector ...is the Forward Tracker, designed to accurately measure the tracks of charged particles close to the proton remnant direction. The association of the correct sub-sets of measured coordinates to the tracks becomes complicated by the high density of charged particles passing through this region. This article presents the application of a combination of an elastic net and a Hopfield net to solve a part of this track finding problem. The results are compared with those obtained using the H1 standard software package.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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