We present an analysis of the K ππ system produced in 10 GeV/ c K + p interactions. We show that the low-mass enchancement between 1.2 and 1.4 GeV/ c 2 on the K ππ mass spectrum is predominantly 1 + throughout, give the relative amplitudes for the decay of this system into K ∗ (890) π and K ρ , and offer new evidence for the presence of two 1 + resonances in this mass region.
No description provided.
DIFFERENTIAL CROSS SECTION FOR THREE MASS BANDS IN Q-REGION. NORMALIZATION UNCERTAIN - NO UNITS FOR D(SIG)/DT GIVEN ON FIGURE. NUMERICAL VALUES TAKEN FROM THE COMPILATION LST7V2 FOX 72B. ERRORS ADDED AS 1/SQRT(EVENTS).
We present the results of a study of 1173 uniquely identified events of the K 0 π + p final state produced in 10 GeV/ c K + p interactions. This final state is dominated by the quasi two-body processes K + p → K 0 N ∗+ (890 p and K + p → K ∗+ (1420) p . The background is very low and there is little overlapping of resonance bands. We present cross sections, t -distributions and decay angular distributions for the contributing reaction channels. Dips are observed near t = 0 in the differential cross sections for all three processes.
BREIT-WIGNER FIT.
NUMERICAL VALUES TAKEN FROM THE COMPILATION LST7V2 FOX 72B.
No description provided.
We have studied the proper time distribution of coherent π + π − decays from a 3 – 10 GeV/ c K L o beam incident on a one meter liquid hydrogen target using a wire spark chamber spectrometer in the 3 0 neutral beam at SLAC. We find ∣(ƒ(0) − ƒ (0))/k∣ = 0.43 ± 0.11 mb , φ(ƒ(0) − ƒ (0)) = -101 0 ± 42 0 .
No description provided.
We observe a K−π+ state at 1786 ± 8 MeV with a width 95 ± 31 MeV in the reaction K−p→K−π+n at 6 GeV/c, from an experiment carried out at the Brookhaven National Laboratory multiparticle spectrometer.
ERROR INCLUDES SYSTEMATIC NORMALIZATION UNCERTAINTY.
The pp total cross section difference between pure transverse spin states was measured in the laboratory momentum range 1–3 GeV/ c . Significant differences were found and these differences show striking energy dependence. This structure is in disagreement with the predictions of simple exchange models.
No description provided.
REVISED DATA (J. D. LESIKAR, PRIV COMM, 19 JUN 1981). NOW CORRECTED FOR COULOMB-NUCLEAR INTERFERENCE. IN ADDITION, THE LOWEST MOMENTUM DATA POINT IS NOW KNOWN TO BE IN ERROR.
We find an increase in ∑ ± production between E cm = 4 and 7 GeV which is consistent with charmed baryon production models. A search for the decay ∧ c − → ∑ ± π ± π − yields no significant peaks.
43 +- 16 ANTI-SIGMAS DETECTED ALTOGETHER.
The production of antineutrons and charged Σ's in e+e− annihilations has been measured at s=4 and 7 GeV and at the ψ(3.1) resonance. Two packages containing spark chambers, steel plates, and scintillation counters were added to each side of the Mark I detector at SPEAR. Antineutrons were identified by annihilations which produced large-angle charged prongs characteristic of a high-Q reaction. The resulting antineutron cross sections and momentum distributions are consistent with previous antiproton results. Charged Σ's were detected by forming mass combinations with the n's and charged tracks in the Mark I. A clear signal is seen in the 7-GeV and ψ data, with little or no signal at s=4 GeV. The increase in Σ± production between 4 and 7 GeV is consistent with simple expectations for charmed-baryon production. A search for the decays Λc−→Σ±π∓π− and Σc*Σc→Λc−π± yields no significant peaks. An upper limit, at the 90% confidence level, of σΛcB(Λc→Σ±π∓π−)<56 pb is set.
No description provided.
THE ANTI-SIGMA PRODUCTION CROSS SECTIONS WERE REPORTED IN T. FERGUSON ET AL., PL 79B, 161 (1978).
NOTE THAT TWICE THE ANTI-NEUTRON CROSS SECTIONS ARE PLOTTED IN THE FIGURES. NUMERICAL VALUES OF DATA ON FIGURES SUPPLIED BY T. FERGUSON.
We have performed a partial-wave analysis of the reaction K−p→KS0π+π−n at 6 GeV/c. We present the results of the analysis of about 4500 events in the low-t region (|t′|<0.2 GeV2) for the dominant waves in the 1200-to-2000-MeV mass range. We observe the 2+ K*(1430) and clear signals for the 1+ Q2(1400) and the 3− K*(1800). We find a new 1− resonance at about 1500 MeV and have some evidence for another 1− resonance at 1800 MeV. We also present the results of a partial-wave analysis as a function of t in the 1430-MeV mass region.
TP DEPENDENCE OF PARTIAL WAVES ALSO STUDIED.
We have measured the asymmetry parameter A and the spin correlation parameter A nn in pp elastic scattering, using the Argonne ZGS polarized proton beam and a polarized proton target. Angular distributions of A and A nn for | t | ≳ 0.2 (GeV/ c ) 2 were obtained at eight momenta between 1.10 and 2 if 2.75 GeV/ c . We find significant structure in both the energy and t -dependence of A nn at these energies. At p lab ≈ 1.34 GeV/ c A nn reaches a very large value of about 0.8–0.9 near θ cm = 90°.
No description provided.
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We report a measurement of the reaction γγ→K+K−π+π− in both tagged and untagged events at PEP. The cross section rises with invariant γγ mass to about 15 nb at 2 GeV and falls slowly at higher masses. We find clear evidence for the processes γγ→φπ+π− and γγ→K*0(892)Kπ. Upper limits (95% C.L.) of 1.5 and 5.7 nb in the mass range from 1.7 to 3.7 GeV are obtained for φρ0 and K*0K¯*0 production, respectively.
No description provided.
No description provided.
Untagged sample, (non-resonant).
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