The updated results of the precise measurements of the processes e+e−→ρ→π+π−, e+e−→ω→π+π−π0 and e+e−→φ→K0LK0S performed by the CMD-2 Collaboration are presented. The update appeared necessary due to ...an overestimate of the integrated luminosity in previous analyses.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The results of the experiment on the measurement of the e+e− → π+π− cross section in a cm energy range of 370–520 MeV are presented. The systematic measurement error is equal to 0.7%. In the vector ...dominance model, the pion electromagnetic radius is calculated using all the CMD-2 data on the pion form factor. The cross section for the production of a muon pair is measured in the energy range of the experiment.
Full text
Available for:
DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We present a measurement of the pion form factor based on e+e− annihilation data from the CMD-2 detector in the energy range 0.6<s<1.0 GeV with a systematic uncertainty of 0.8%. A data sample is five ...times larger than that used in our previous measurement.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Harsh radiation conditions, including the ones expected for the operation with High-Luminosity LHC, require detailed and careful quality control of any gas detector from the very beginning stage of ...assembly. The existing probe methods for cathode boards QC are able to find shorts to ground, shorts between pads, and breaks in the readout line at the initial stage of manufacturing. The cosmic test requires fully assembled detectors and reveals pads with absent or low amplitude analog signals associated with resistance in the readout trace line. In the current work, we propose the direct method of such a defect recognition for both bare cathode boards and fully assembled detectors and demonstrate the examples of a successful cure.
This paper presents a first attempt to estimate the volume of water required for the maintenance of freshwater-dependent ecosystems at the global scale. This total environmental water requirement ...consists of ecologically relevant low-flow and high-flow components and depends upon the objective of environmental water management. Both components are related to river flow variability and estimated by conceptual rules from discharge time series simulated by the global hydrology model. A water stress indicator is further defined, which shows what proportion of the utilizable water in world river basins is currently withdrawn for direct human use and where this use is in conflict with environmental water requirements. The paper presents an estimate of environmental water requirements for 128 major river basins and drainage regions of the world. It is shown that approximately 20 to 50 percent of the mean annual river flow in different basins needs to be allocated to freshwater-dependent ecosystems to maintain them in fair conditions. This is unlikely to be possible in many developing countries in Asia and North Africa, in parts of Australia, North America, and Europe, where current total direct water withdrawals (primarily for irrigation) already tap into the estimated environmental water requirements. Over 1.4 billion people currently live in river basins with high environmental water stress. This number will increase as water withdrawals grow and if environmental water allocations remain beyond the common practice in river basin management. This paper suggests that estimates of environmental water requirements should be the integral part of global water assessments and projections of global food production.
Full text
Available for:
BFBNIB, NUK, PILJ, SAZU, UL, UM, UPUK
The cross-section of the process e+e−→π+π− has been measured using about 114000 events collected by the CMD-2 detector at the VEPP-2M e+e− collider in the center-of-mass energy range from 0.61 to ...0.96 GeV. Results of the pion form factor determination with a 0.6% systematic uncertainty are presented. The following values of the ρ- and ω-meson parameters were found: Mρ=(776.09±0.81) MeV, Γρ=(144.46±1.55) MeV, Γ(ρ→e+e−)=(6.86±0.12) keV, Br(ω→π+π−)=(1.33±0.25)%. Implications for the hadronic contribution to the muon anomalous magnetic moment are discussed.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Testing TGC detectors in a high rate environment Smakhtin, Vladimir
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2002, Volume:
494, Issue:
1
Journal Article
Peer reviewed
The TGC detectors are expected to provide the Muon trigger for the ATLAS detector in the forward region of the ATLAS Muon Spectrometer. The TGC detectors are expected to provide a trigger signal ...within
25
ns
of the bunch spacing of the LHC accelerator, with an efficiency exceeding 95%, while exposed to an effective photon and neutron background ranging from 30 to
500
Hz/
cm
2
. In order to qualify the detectors and start its mass production, they have been exposed to a MUON beam, while being irradiated with photons at the GIF facility at CERN. The results of such an exposure and the corresponding behavior of the detectors show that the TGC technique satisfies the requirements for its use in the ATLAS Muon Spectrometer.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The superconducting solenoid is designed to provide 1.5 T magnetic field in the CMD-3 detector. Its dimensions are 0.7 m in diameter and 0.9 m in length. The superconducting coil is made of two ...layers of NbTi/Cu cable 0.87 mm in diameter. The solenoid is protected from quench by shunts, which are uniformly distributed along the coil. The total resistance of the shunts is about 40 . The superconducting coil has a minimal radiation thickness compared with other solenoids (0.085 ). The superconducting coil is indirectly cooled by liquid helium being in nucleate pool boiling state at 4.2 K. High purity aluminum strips were used to keep the solenoid at 4.2 K. The magnet system was tested for liquid helium efficiency. In May 2007, the solenoid, surrounded by a dummy iron yoke, was charged to its design current. The quench behavior of the solenoid is discussed.
Using 3.07 pb
−1 of data collected in the energy range 0.60–0.97 GeV by CMD-2, about 150 events of the process e
+e
−→
π
+
π
−
π
+
π
− have been selected. The energy dependence of the cross section ...agrees with the assumption of the
a
1(1260)
π intermediate state which is dominant above 1 GeV. For the first time
π
+
π
−
π
+
π
− events are observed at the
ρ meson energy. Under the assumption that all these events come from the
ρ meson decay, the value of the cross section at the
ρ meson peak corresponds to the following decay width:
Γ(ρ
0→π
+π
−π
+π
−)=(2.8±1.4±0.5)
keV
or to the branching ratio
B(ρ
0→π
+π
−π
+π
−)=(1.8±0.9±0.3)·10
−5.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
PDF
