Test of the first BIL tracking chamber for the ATLAS muon spectrometer Avolio, G.; Bagnaia, P.; Baroncelli, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
05/2004, Letnik:
523, Številka:
3
Journal Article
Recenzirano
The first Barrel Inner Large chamber of the Monitored Drift Tube (MDT) tracking detector for the muon spectrometer of the ATLAS experiment has been tested with a high-energy muon beam. After a ...description of the MDT characteristics, we present the test beam experimental set-up, the data analysis techniques and discuss the results. The chamber was operated with a Ar(93%)–CO
2(7%) gas mixture at 3-bar pressure. The performance studies include the chamber calibration, the single-tube resolution, efficiency and electronic noise, and their behaviour as a function of the high-voltage setting and discriminator threshold.
A set of seven musical instruments and two instruments cares from the ‘Fondo Antico della Biblioteca del Sacro Convento’ in Assisi, Italy, were investigated through neutron and X-ray imaging ...techniques. Historical and scientific interests around ancient musical instruments motivate an intense research effort for their characterization using non-destructive and non-invasive techniques. X-ray and neutron tomography/radiography were applied to the study of composite material samples containing wood, hide and metals. The study was carried out at the NEUTRA beamline, PSI (Paul Scherrer Institute, Switzerland). Results of the measurements provided new information on the composite and multi-scale structure, such as: the internal structure of the samples, position of added materials like metals, wood fiber displays, deformations, presence of adhesives and their spatial distribution and novel insight about construction methods to guide the instruments’ restoration process.
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.
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.
Vascular dementia (VaD) is defined as a loss of cognitive function resulting from ischemic, hypoperfusive, or hemorrhagic brain lesions due to cerebrovascular disease or cardiovascular pathology. The ...main types of VaD are: Small Vessel Disease Dementia (sVAD), Large vessel disease dementia, hypoperfusive-ischemic dementia and hemorragic dementia. The sVAD is divided into two main categories: subcortical ischemic vascular dementia (SIVD) and cortical dementia. Currently, no drugs are approved for the treatment of VaD. This study aimed to determine whether rivastigmine, a second generation cholinesterase inhibitor with selectivity for the CNS, with capacity to inhibit both acetylcholinesterase (AChE) and butyryl-cholinesterase (BuChE), slows the rate of cognitive decline associated with VaD.
Study subjects were 27 male and 43 female outpatients aged 80.03±6.53 years, with Mini-Mental State Examination (MMSE) score ranging batween 22 and 12, affected by VaD. They were included in the study if they were undergoing pharmacological treatment with acetylsalicylic acid 100 mg for at least six months. Patients were divided into two groups: one group was treated with ASA 100 mg and rivastigmine patch 9.5 mg (Rivastigmine group), the other just with ASA 100 mg (ASA group). All patients were followed for 6 months, with a first evaluation (T0) and a second examination after six mounths of treatment (T1).
Statistically data proved as the Rivastigmine group showed constant values at MMSE, compared with patients of the ASA group who experienced decline of their cognitive performances. The same result was found in CDR, ADL, GDS and NPI scales. It is remarkable to underline as Rivastigmine-treated patients had a mean improvement in GDS scales, in comparison with patients of the ASA group who showed a worsening of mood.
Rivastigmine-therapy improves cognitive performance in elderly with SIVD.
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.
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.
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