The tracking detector of the KLOE experiment Adinolfi, M; Ambrosino, F; Andryakov, A ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2002, Letnik:
488, Številka:
1
Journal Article
Recenzirano
The design and construction of the large Drift Chamber for the KLOE experiment at the Frascati φ-factory, DAΦNE, are described. The relevant aspects of the various elements of the detector are ...reviewed together with a description of the track reconstruction program and of the calibration procedures. The performance of the detector based on measurements with cosmic rays and with e
+e
− colliding beams during DAΦNE commissioning is presented.
The trigger system of the KLOE experiment Adinolfi, M; Ambrosino, F; Antonelli, M ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2002, Letnik:
492, Številka:
1
Journal Article
Recenzirano
We present the design of the trigger system for the KLOE experiment at the Frascati
φ-factory DAΦNE. The detector consists of a large-volume drift chamber and a calorimeter both immersed in a
0.52
T
...solenoidal field. The trigger, structured with a first- and a second-decision level, is based on the multiplicity of energy deposits in the calorimeter and of hits in the drift chamber. The selection criteria are described and the efficiency for detecting
φ decays is evaluated using data.
We have measured the cross section σ(e+e−→π+π−γ) at an energy W=mϕ=1.02 GeV with the KLOE detector at the electron–positron collider DAΦNE. From the dependence of the cross section on the invariant ...mass of the two-pion system, we extract σ(e+e−→π+π−) for the mass range 0.35<s<0.95 GeV2. From this result, we calculate the pion form factor and the hadronic contribution to the muon anomaly, aμ.
The QCAL tile calorimeter of KLOE Adinolfi, M; Ambrosino, F; Antonelli, M ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2002, Letnik:
483, Številka:
3
Journal Article
Recenzirano
The quadrupole tile calorimeters of KLOE (QCAL) are two compact detectors placed close to the interaction point and surrounding the focusing quadrupoles. Their purpose is to increase the hermeticity ...of KLOE calorimetry. Each QCAL consists of a sampling structure of lead plates and scintillator tiles with wavelength shifter (WLS) fibers and mesh photomultiplier readout arranged in 16 azimuthal sectors. The arrangement of WLS fibers allows the measurement of the longitudinal position of the showers from time of flight. In this paper we describe the QCAL design and assembly and present preliminary results obtained with both cosmic rays and photons from K
L decays. The time and energy calibration procedures are also discussed in detail.
We have measured the ratio Rϕ=BR(ϕ→η′γ)/BR(ϕ→ηγ) by looking for the radiative decays ϕ→η′γ and ϕ→ηγ into the final states π+π−7γ and 7γ, respectively, in a sample of ∼1.4×109ϕ mesons produced at the ...Frascati ϕ factory. We obtain Rϕ=(4.77±0.09stat±0.19syst)×10−3, from which we derive BR(ϕ→η′γ)=(6.20±0.11stat±0.25syst)×10−5. Assuming the η′ has zero gluonium content, we extract the pseudoscalar mixing angle in the quark-flavor basis, φP=(41.4±0.3stat±0.7syst±0.6th)°. Combining the value of Rϕ with other constraints, we estimate the fractional gluonium content of the η′ to be Z2=0.14±0.04 and the mixing angle to be φP=(39.7±0.7)°.
We have designed and built the facilities to assemble the inner layer of the precision tracking chambers (Monitored Drift Tubes, MDT) for the Muon Spectrometer of the ATLAS Experiment at LHC. This ...article describes in detail the tooling, the procedures and the quality control equipment used in the chambers assembly. Data are presented from the X-ray tomograph at CERN showing that the required chamber mechanical precision has been achieved.
Among some 400 million KSKL pairs produced in e+e− annihilations at DAΦNE, ∼6500 each of KS→π+e−ν¯ and KS→π−e+ν decays have been observed with the KLOE detector. From these, the ratio ...Γ(KS→πeν)/Γ(KS→π+π−)=(10.19±0.13)×10−4 is obtained, improving the accuracy on BR(KS→πeν) by a factor of four and providing the most precise test of the ΔS=ΔQ rule. From the partial width Γ(KS→πeν), a value for f+K0(0)×Vus is obtained that is in agreement with unitarity of the quark-mixing matrix. The lepton charge asymmetry AS=(1.5±9.6stat±2.9syst)×10−3 is compatible with the requirements of CPT invariance. The form-factor slope agrees with recent results from semileptonic KL and K+ decays. These are the first measurements of the charge asymmetry and form-factor slope for semileptonic KS decays.
The KLOE electromagnetic calorimeter Adinolfi, M; Ambrosino, F; Antonelli, A ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2002, Letnik:
482, Številka:
1-2
Journal Article
Recenzirano
The KLOE detector was designed primarily for the study of CP violation in neutral kaon decays at DAΦNE, the Frascati φ-factory. The detector consists of a tracker and an electromagnetic calorimeter. ...A lead-scintillating-fiber sampling calorimeter satisfies best the requirements of the experiment, providing adequate energy resolution and superior timing accuracy. We describe in the following the construction of the calorimeter, its calibration and how the calorimeter information is used to obtain energy, point of entry and time of the arrival of photons, electrons and charged particles. With e+e− collision data at DAΦNE for an integrated luminosity of some 2pb−1 we find for electromagnetic showers, an energy resolution of 5.7%/E(GeV) and a time resolution of 54/E(GeV) ps. We also present a measurement of efficiency for low energy photons.
We present a measurement of the K–π vector current form-factor parameters for the decay KL→π±e∓ν. We use 328 pb−1 of data collected in 2001 and 2002, corresponding to ∼2 million Ke3 events. ...Measurements of semileptonic form factors provide information about the dynamics of the strong interaction and are necessary for evaluation of the phase-space integral IKe needed to measure the CKM matrix element |Vus| for KL→π±e∓ν decays. Our result is λ+=(28.6±0.5±0.4)×10−3 for a linear fit, and λ+′=(25.5±1.5±1.0)×10−3, λ+″=(1.4±0.7±0.4)×10−3 for a quadratic fit.
We measured, with the KLOE detector, the spectrum of π+π− invariant mass in a sample of 6.7×105e+e−→π+π−γ events with the photon at large polar angle (θγ>45°) at a centre of mass energy s around the ...ϕ mass. We observe in this spectrum a clear contribution from the intermediate process ϕ→ f0(980)γ. A sizeable effect is also observed in the distribution of the pion forward–backward asymmetry. We use different theoretical models to fit the spectrum and we determine the f0 mass and coupling constants to the ϕ, to π+π− and to KK¯.
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