Charged current data of a spark chamber neutrino experiment at the 70 GeV Serpukhov accelerator (10 200 events in the v beam and 3600 events in the v beam with energies up to 30 GeV) have been analyzed. Total neutrino and antineutrino cross sections and v -distributions are obtained.
Measured charged current total cross section.
Measured charged current total cross section.
In this paper a comparison of the general features of the reactions K ± p→Q ± p (1) at incident momentum 8.25 GeV/ c is presented. The relevant data derive from events yielding four-constraint fits to the reactions K ± p→K ± π + π − p in exposures of the CERN 2m HBC to RF-separated K + and K − beams. The (K ππ ) effective mass distributions, production angular distributions in the Q region (1.2⩽ M (K ππ )⩽1.5 GeV) and corresponding decay angular distributions are exhibited, and background effects due to N ∗ and Δ production are systematically studied. In particular, it is found that the distributions d σ /d t ′ and d σ /d t for reactions (1) are adequately described by exponential functions over the interval 0.05–0.35 GeV 2 , and exhibit a cross-over effect for momentum transfer squared −0.1 GeV 2 . For both reactions a flattening of d σ /d t ′ for t ′ < 0.05 GeV 2 is observed. By studying the Chew-Low plots and the effects of the different cuts it was found that this flattening cannot be attributed to amplitudes with net s -channel helicity flip different from zero, at least at these energies.
ABOUT 7 PCT RELATIVE NORMALIZATION UNCERTAINTY FOR K+ AND K- SAMPLES.
FITS TO D(SIG)/DT AND D(SIG)/DTP FOR Q+ AND Q- PRODUCTION TO DETERMINE CROSS-OVER POSITIONS. DATA HAVE MASS CUTS TO SELECT K*0 AND REMOVE DEL++ AND DEL0. MIN IS THE MINIMUM VALUE OF -T FOR THE RELEVANT (K PI PI) MASS.
We study the processes e+e- --> K+ K- pi+pi-gamma, K+ K- pi0pi0gamma, and K+ K- K+ K-gamma, where the photon is radiated from the initial state. About 84000, 8000, and 4200 fully reconstructed events, respectively, are selected from 454 fb-1 of BaBar data. The invariant mass of the hadronic final state defines the \epem center-of-mass energy, so that the K+ K- pi+pi- data can be compared with direct measurements of the e+e- --> K+ K- pi+pi- reaction. No direct measurements exist for the e+e- --> K+ K-pi0pi0 or e+e- --> K+ K-K+ K- reactions, and we present an update of our previous result with doubled statistics. Studying the structure of these events, we find contributions from a number of intermediate states, and extract their cross sections. In particular, we perform a more detailed study of the e+e- --> phi(1020)pipigamma reaction, and confirm the presence of the Y(2175) resonance in the phi(1020) f0(980) and K+K-f0(980) modes. In the charmonium region, we observe the J/psi in all three final states and in several intermediate states, as well as the psi(2S) in some modes, and measure the corresponding product of branching fraction and electron width.
The cross section for the reaction E+ E- --> K+ K- PI+ PI- measured with ISR data. Statistical errors only.
Cross section measurements for the reaction E+ E- --> K*(892)0 K- PI+. Statistical errors only.
Cross section measurements for the reaction E+ E- --> PHI PI+ PI-. Statistical errors only.
We study the processes $e^+ e^-\to K_S^0 K_L^0 \gamma$, $K_S^0 K_L^0 \pi^+\pi^-\gamma$, $K_S^0 K_S^0 \pi^+\pi^-\gamma$, and $K_S^0 K_S^0 K^+K^-\gamma$, where the photon is radiated from the initial state, providing cross section measurements for the hadronic states over a continuum of center-of-mass energies. The results are based on 469 fb$^{-1}$ of data collected with the BaBar detector at SLAC. We observe the $\phi(1020)$ resonance in the $K_S^0 K_L^0$ final state and measure the product of its electronic width and branching fraction with about 3% uncertainty. We present a measurement of the $e^+ e^-\to K_S^0 K_L^0 $ cross section in the energy range from 1.06 to 2.2 GeV and observe the production of a resonance at 1.67 GeV. We present the first measurements of the $e^+ e^-\to K_S^0 K_L^0 \pi^+\pi^-$, $K_S^0 K_S^0 \pi^+\pi^-$, and $K_S^0 K_S^0 K^+K^-$ cross sections, and study the intermediate resonance structures. We obtain the first observations of \jpsi decay to the $K_S^0 K_L^0 \pi^+\pi^-$, $K_S^0 K_S^0 \pi^+\pi^-$, and $K_S^0 K_S^0 K^+K^-$ final states.
Cross section measurement for PHI(1020).
Mass measurement for PHI(1020).
Measurement of the PHI(1020) width.
None
Axis error includes +- 0.0/0.0 contribution (?////NOT GIVEN).
Axis error includes +- 0.0/0.0 contribution (?////NOT GIVEN).
No description provided.
Joint decay distributions have been studied in the reaction K + p → K ∗o (1420)Δ ++ at 5.0 GeV/ c in the transversity spin reference frame. Two alternative spin-parity assignments 2 + and 3 − for the K ∗ resonance have been considered and a comparison with the quark-model predictions has been made. The predictions of the quark model are equally well satisfied by the experimental results for both the 2 + and 3 − spin-parity assignments.
No description provided.
None
USING METHOD (A), SEE THE ARTICLE.
USING METHOD (B), SEE THE ARTICLE.
The results of the study of the π + p→K + ∑ + (1) and π + p→K + ∑ + (1385) (2) reactions at 12 GeV/ c are presented. The differential cross sections d σ /d t in| t min |<| t |<0.8 (GeV/ c ) 2 momentum transfer range are measured. The ∑ + polarisation for | t |<0.5 (GeV/ c ) 2 for reaction (1) is defined. Binary reactions (1) and (2) were selected by analyzing the missing mass spectra for the forward emitted fast K + meson. The total cross sections in the studied momentum transfer range are 20.2±2.4 μ b and 7.3±1.1 μ b for the reactions (1) and (2) respectively. The experimental results are compared with the predictions of the Regge models which take into account rescattering and secondary singularities.
SYSTEMATIC ERRORS INCLUDED.
No description provided.
No description provided.
None
No description provided.
No description provided.
We present a measurement of the cross section of the process $e^+e^-\to\pi^+pi^-\psi(2S)$ from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at the PEP-II $e^+e^-$ storage rings. The study is based on 298 fb$^{-1}$ of data recorded with the BaBar detector. A structure is observed in the cross-section not far above threshold, near 4.32 GeV. We also investigate the compatibility of this structure with the Y(4260) previously reported by this experiment.
The measured c.m. energy dependence of the cross section with statistical errors only.. Bins with no recorded data are shown as a 'dash'.
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