Application Specific Integrated Circuits, ASICs, similar to those envisaged for the readout electronics of the central calorimeters of detectors for a future lepton collider have been exposed to ...high-energy electromagnetic showers. A salient feature of these calorimeters is that the readout electronics will be embedded into the calorimeter layers. In this article it is shown that interactions of shower particles in the volume of the readout electronics do not alter the noise pattern of the ASICs. No signal at or above the MIP level has been observed during the exposure. The upper limit at the 95% confidence level on the frequency of fake signals is smaller than
1
×
10
−
5
for a noise threshold of about 60% of a MIP. For ASICs with similar design to those which were tested, it can thus be largely excluded that the embedding of the electronics into the calorimeter layers compromises the performance of the calorimeters.
A first measurement is reported of the longitudinal proton structure function FL(X, Q(2)) at the ep collider HERA. It is based on inclusive deep inelastic e(+)p scattering cross section measurements ...with a positron beam energy of 27.5 GeV and proton beam energies of 920, 575 and 460 GeV. Employing the energy dependence of the cross section, FL is measured in a range of squared four-momentum transfers 12 <= Q2 <=, 90 GeV2 and low Bjorken x 0.00024 <= x <= 0.0036. The F-L values agree with higher order QCD calculations based on parton densities obtained using cross section data previously measured at HERA. (C) 2008 Elsevier B.V. All rights reserved.
A highly granular electromagnetic calorimeter with scintillator strip readout is being developed for future linear collider experiments. A prototype of 21.5 X0 depth and 180×180mm2 transverse ...dimensions was constructed, consisting of 2160 individually read out 10×45×3mm3 scintillator strips. This prototype was tested using electrons of 2–32 GeV at the Fermilab Test Beam Facility in 2009. Deviations from linear energy response were less than 1.1%, and the intrinsic energy resolution was determined to be (12.5±0.1(stat.)±0.4(syst.))%∕EGeV⊕(1.2±0.1(stat.)−0.7+0.6(syst.))%, where the uncertainties correspond to statistical and systematic sources, respectively.
A first prototype of a scintillator strip-based electromagnetic calorimeter was built, consisting of 26 layers of tungsten absorber plates interleaved with planes of 45×10×3mm3 plastic scintillator ...strips. Data were collected using a positron test beam at DESY with momenta between 1 and 6GeV/c. The prototype׳s performance is presented in terms of the linearity and resolution of the energy measurement. These results represent an important milestone in the development of highly granular calorimeters using scintillator strip technology. A number of possible design improvements were identified, which should be implemented in a future detector of this type. This technology is being developed for a future linear collider experiment, aiming at the precise measurement of jet energies using particle flow techniques.
A prototype silicon–tungsten electromagnetic calorimeter (ECAL) for an international linear collider (ILC) detector was installed and tested during summer and autumn 2006 at CERN. The detector had ...6480 silicon pads of dimension
1
×
1
cm
2
. Data were collected with electron beams in the energy range 6–45
GeV. The analysis described in this paper focuses on electromagnetic shower reconstruction and characterises the ECAL response to electrons in terms of energy resolution and linearity. The detector is linear to within approximately the 1% level and has a relative energy resolution of
(
16.53
±
0.14
(
stat
)
±
0.4
(
syst
)
)
/
E
(
GeV
)
⊕
(
1.07
±
0.07
(
stat
)
±
0.1
(
syst
)
)
(
%
)
. The spatial uniformity and the time stability of the ECAL are also addressed.