The momentum distribution of electrons from semileptonic decays of charm and bottom quarks for midrapidity |y|<0.35 in p+p collisions at {radical}s = 200 GeV is measured by the PHENIX experiment at ...the Relativistic Heavy Ion Collider over the transverse momentum range 2 < p{sub T} < 7 GeV/c. The ratio of the yield of electrons from bottom to that from charm is presented. The ratio is determined using partial D/{bar D} {yields} e{sup {+-}} k{sup {-+}} (K unidentified) reconstruction. It is found that the yield of electrons from bottom becomes significant above 4 GeV/c in p{sub T}. A fixed-order-plus-next-to-leading-log perturbative quantum chromodynamics calculation agrees with the data within the theoretical and experimental uncertainties. The extracted total bottom production cross section at this energy is {sigma} b{bar b} = 3.2{sub -1.1}{sup +1.2}(stat){sub -1.3}{sup +1.4}(syst){micro}b.
New experimental results on ratio
R
dp
of the quasielastic charge-exchange yield at the outgoing proton angle
θ
p
,lab
= 0° for the
nd
→
p
(
nn
) reaction to the elastic
np
→
pn
charge-exchange ...yield, are presented. The measurements were carried out at the Nuclotron of the Veksler and Baldin Laboratory of High Energies of the JINR (Dubna) at the neutron-beam kinetic energies of 0.55, 0.8, 1.0, 1.2, 1.4, 1.8, and 2.0 GeV. The intense neutron beam with small momentum spread was produced by breakup of deuterons which were accelerated and extracted to the experimental hall. In both reactions mentioned above the outgoing protons with the momenta
p
p
approximately equal to the neutron-beam momentum
p
n
,beam
were detected in the directions close to the direction of incident neutrons, i.e., in the vicinity of the scattering angle
θ
p
,lab
= 0°. Measured in the same data-taking runs, the angular distributions of the charge-exchange-reaction products were corrected for the well-known instrumental effects and averaged in the vicinity of the incident-neutron-beam direction. These corrected angular distributions for every of
nd
→
p
(
nn
) and
np
→
pn
charge-exchange processes were proportional to the differential cross sections of the corresponding reactions. The data were accumulated by Delta-Sigma setup magnetic spectrometer with two sets of multiwire proportional chambers located upstream and downstream of the momentum analyzing magnet. Inelastic processes were considerably reduced by the additional detectors surrounding the hydrogen and deuterium targets. The time-of-flight system was applied to identify the detected particles. The accumulated data treatment and analysis, as well as possible sources of the systematic errors are discussed.
. In the Doha Round, trade facilitation is the negotiating issue in which the ‘implementation issue’ is most prominent. At the WTO (the Doha Development Agenda) the international community has ...approached the implementation problem as a challenge to restore mercantilist balance rather than as a need to build good economics into future agreements. The international community has taken on aggressively the development dimensions of trade facioitation through the development banks, bilateral aid agencies and other specialized institutions. Considerable funding has been provided. Though little progress has been made through WTO negotiations, the content of these development programs is supportive of development.
The SPHERE-2 balloon-borne detector designed for extensive air shower (EAS) observations using EAS optical Vavilov-Cherenkov radiation (``Cherenkov light''), reflected from the snow-covered surface ...of Lake Baikal is described. We briefly discuss the concept behind the reflected Cherenkov light method, characterize the conditions at the experimental site and overview the construction of the tethered balloon used to lift the SPHERE-2 telescope above the surface. This paper is mainly dedicated to a detailed technical description of the detector, including its optical system, sensitive elements, electronics, and data acquisition system (DAQ). The results of some laboratory and field tests of the optical system are presented.
The analysing power of the reaction \({\rm n} {\rm p} \rightarrow {\rm p} {\rm p} \pi^{-}\) for neutron energies between threshold and 570 MeV has been determined using a transversely polarised ...neutron beam at PSI. The reaction has been studied in a kinematically complete measurement using a time-of-flight spectrometer with large acceptance. Analysing powers have been determined as a function of the c.m. pion angle in different regions of the proton-proton invariant mass. They are compared to other data from the reactions \({\rm n} {\rm p} \rightarrow {\rm p} {\rm p} \pi^{-}\) and \({{\rm p} {\rm p} \rightarrow {\rm p} {\rm p} \pi^{0}}\). The np elastic scattering analysing power was determined as a by-product of the measurements.
This article addresses the transformation of the role played by environmental nongovernmental organizations in global politics. Such a change is placed into a larger framework of growing ecological ...concerns, the evolving political means to address them, and the overall mutation of the global state system. The relationship among environmental organizations, states, and intergovernmental institutions is framed as being an increasingly strategic one, where states seek to instrumentalize environmental organizations in order to prevail, while environmental organizations seek to take over functions previously held by states.
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