Tapper, R.J.
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CROSS-SECTIONS AND SCALING VARIABLE DISTRIBUTIONS OF NEUTRAL AND CHARGED CURRENT NEUTRINO NUCLEON INTERACTIONS FROM A LOW-ENERGY NARROW BAND BEAM

Baltay, C. ; French, H. ; Hibbs, M. ; et al.
Phys.Rev.Lett. 44 (1980) 916-919, 1980.
Inspire Record 157494 DOI 10.17182/hepdata.20725

This Letter compares neutral-current and charged-current scaling-variable distributions in neutrino-nucleon interactions induced by a narrow-band beam at Brookhaven National Laboratory; the x distribution of neutral-current events has been reported previously. The first measurement of flux-normalized neutrino cross sections from a narrow-band beam in the energy range Eν=3−9 GeV is also presented.

1 data table
Table 1

Measured charged current total cross section.


An Experimental Test of Exchange Degeneracy in the Reactions $\pi^+ p \to K^+ \Sigma^+$, $\pi^+ p \to K^+ \Sigma^+$ (1385) and Their Line Reversed Partners

Berglund, A. ; Buran, T. ; Carlson, P.J. ; et al.
Nucl.Phys.B 166 (1980) 25-61, 1980.
Inspire Record 143535 DOI 10.17182/hepdata.34526

A description is given of an experimental study of exchange degeneracy (EXD) in hypercharge-exchange reactions using the line-reversed partners π + p→K + Σ + (K − p→ π − Σ + ) and π + p→ K + Σ + (1385) (K − p→ π − Σ + (1385)) at incident momenta of 7.0 and 10.1 GeV/ c . Both pairs of reaction were measured in the same apparatus, with particular care being taken to minimize relative normalization errors. For the Σ production reactions we present high statistics measurements of the differential cross sections and polarizations from t ′=0 to large t . The general trends of the data agree with naive expectations from weak EXD. The cross-section difference in the extreme forward direction at the higher momentum is consistent with zero and there is a general reduction in the cross-section differences going from the lower to the higher momentum. The polarizations are approximately equal in magnitude and of opposite sign between the two reactions. On the other hand, the data do not agree with the detailed predictions of EXD. The slope for the positive reaction is systematically steeper in the forward region than for the negative reaction and there is a complex s and t dependence for the cross-section differences including a cross-over at t ⋍ −0.8( GeV /c) 2 . For the Σ(1385) production reactions, we present differential cross-section measurements in the forward region (| t |<0.3(GeV/ c ) 2 ). The cross-section differences are substantial and essentially constant over the s and t ranges studied.

2 data tables
Table 1

THESE RESULTS WERE BRIEFLY REPORTED IN A. BERGLUND ET AL., PL 73B, 369 (1978), THE RECORD OF WHICH INCLUDES THE TABULATED DATA.

Table 2

THE RESULTS AT 10.1 GEV WERE FIRST PUBLISHED IN A. BERGLUND ET AL., PL 60B, 117 (1975), THE RECORD OF WHICH INCLUDES THE TABULATED DATA.


Evidence for Direct $\gamma$ Production at Large $x$ in $\psi$ (3100) Decay

Ronan, M.T. ; Trippe, T.G. ; Barbaro-Galtieri, A. ; et al.
Phys.Rev.Lett. 44 (1980) 367, 1980.
Inspire Record 142946 DOI 10.17182/hepdata.20700

The inclusive γ and π0 momentum spectra from ψ(3100) decay have been measured in e+e− annihilation at SPEAR. When the γ spectrum is compared with that expected from π0 decay, an excess of high-momentum γ's is observed. This excess is compared with that predicted by quantum chromodynamics for the decay of the ψ into a γ and two gluons.

4 data tables
Table 1

THE STATISTICAL AND SYSTEMATIC ERRORS ARE GIVEN SEPARATELY AS WELL AS COMBINED IN QUADRATURE FOR THE QUOTED TOTAL ERROR.

Table 2

THE STATISTICAL AND SYSTEMATIC ERRORS ARE GIVEN SEPARATELY AS WELL AS COMBINED IN QUADRATURE FOR THE QUOTED TOTAL ERROR. SYSTEMATIC ERROR IS 17 PCT.

Table 3

QUOTED ERRORS ARE STATISTICAL. SYSTEMATIC ERROR IS 20 PCT. ONLY HALF THE SUM OF THE PI+ AND PI- CROSS SECTIONS IS PLOTTED IN THE FIGURE IN THE JOURNAL.

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Measurement of the Parameters of the $\psi^{\prime\prime}$(3770) Resonance

Abrams, G.S. ; Alam, M.S. ; Blocker, C.A. ; et al.
Phys.Rev.D 21 (1980) 2716, 1980.
Inspire Record 142644 DOI 10.17182/hepdata.24185

We present a measurement of the cross section for hadron production by e+e− annihilation in the vicinity of the previously observed resonance near 3.77 GeV. The data are used to determine the parameters of the ψ(3770) resonance. The values found are: mass, 3764±5 MeV/c2, total width, 23.5±5 MeV, and partial width to electron pairs, 276±50 eV.

3 data tables
Table 1

THESE RESULTS ARE ALSO IN THE THESIS OF R. H. SCHINDLER, SLAC-219 (1979), THE RECORD OF WHICH CONTAINS THE TABULATED CROSS SECTIONS.

Table 2

BREIT-WIGNER RESONANCE PLUS BACKGROUND FIT TO RADIATIVELY CORRECTED DATA YIELDS RESONANCE MASS OF 3764 +- 5 MEV, TOTAL WIDTH OF 23.5 +- 5 MEV AND PARTIAL WIDTH TO ELECTRON PAIRS OF 276 +- 50 EV.

Table 3

PEAK CROSS SECTION FOR D MESON PAIR PRODUCTION AT PSI(3770) RESONANCE. J/PSI, PSI(3684) AND CONTINUUM BACKGROUND (R=2.5) SUBTRACTED.


Proton Spectra From 800-{MeV} Protons on Selected Nuclides

Chrien, R.E. ; Krieger, T.J. ; Sutter, R.J. ; et al.
Phys.Rev.C 21 (1980) 1014, 1980.
Inspire Record 143625 DOI 10.17182/hepdata.5224

The emission of protons from targets of Li6, Li, C12, Al27, Ca40, V51, Zr90, and Pb under bombardment from 800 MeV protons has been studied using a high resolution proton spectrometer. Spectra were measured at laboratory scattering angles of 5°, 7°, 9°, 11°, 13°, 15°, 20°, 25°, and 30° with special emphasis on the quasifree region. Outgoing momenta corresponding to the region of pion production were examined at 11° and 15°. Absolute cross sections have been derived by reference to known (p,p) scattering data at 800 MeV. The quasifree scattering has been compared to a distorted-wave impulse approximation analysis by summing over the unobserved (struck) nucleon. The systematics of proton production and the applicability of the distorted-wave impulse approximation analyses are discussed. NUCLEAR REACTIONS (p,p′) on Li6, Li, C12, Al27, Ca40, V51, Zr90, Pb; Ep=800 MeV, θL=5° to 30°; quasielastic scattering, DWIA analysis.

50 data tables
Table 1

APPROXIMATE SYSTEMATIC CROSS SECTION ERROR IS EQUAL TO +-6.5%.

Table 2

APPROXIMATE SYSTEMATIC CROSS SECTION ERROR IS EQUAL TO +-6.5%.

Table 3

APPROXIMATE SYSTEMATIC CROSS SECTION ERROR IS EQUAL TO +-6.2%.

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Observation of Charmed Baryon Production in e+ e- Annihilation

Abrams, G.S. ; Alam, M.S. ; Blocker, C.A. ; et al.
Phys.Rev.Lett. 44 (1980) 10, 1980.
Inspire Record 142743 DOI 10.17182/hepdata.20754

A peak in the pK−π+ and p¯K+π− invariant-mass spectra at 2.285±0.006 GeV/c2 is observed, which is associated with the lowest-lying charmed baryon (Λc). A cross section times branching ratio of 0.037±0.012 nb at Ec.m.=5.2 GeV is measured with a substantial fraction of the events produced with an equal recoiling mass. New measurements of inclusive p and Λ cross sections are also presented, allowing an estimate of the branching ratio B(Λc→pK−π+)=0.022±0.010.

3 data tables
Table 1

THE TOTAL INCLUSIVE CHARMED LAMBDA CROSS SECTION IS DERIVED FROM THE OBSERVED PRODUCTION RATE VIA THE <P K- PI+> CHANNEL USING THE STEP IN INCLUSIVE PROTON PRODUCTION AT THE CHARMED-BARYON THRESHOLD AND REASONABLE ASSUMPTIONS. THE BRANCHING RATIO (LAMBDA/C+ --> P K- PI+) IS THEN 2.2 +- 1.0 PCT.

Table 2

ACTUALLY TWICE THE INCLUSIVE ANTI-PROTON CROSS SECTION (EACH BARYON PAIR IS COUNTED TWICE).

Table 3

EACH BARYON PAIR PRODUCED IS OF COURSE COUNTED TWICE IN THIS CROSS SECTION.


Inclusive Production of $D$ and $K$ Mesons in $e^+ e^-$ Annihilation

Piccolo, M. ; Peruzzi, I. ; Rapidis, P.A. ; et al.
Phys.Lett.B 86 (1979) 220-224, 1979.
Inspire Record 141018 DOI 10.17182/hepdata.27301

We present measurements of the cross section for inclusive D and K meson production in e + e − annihilation in the center of mass energy range 3.6 to 5.8 GeV. D production accounts for most of the increase in the total cross section for hadron production in e + e − annihilation at energies above 4 GeV.

3 data tables
Table 1

No description provided.

Table 2

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Table 3

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POLARIZED CROSS-SECTION MEASUREMENTS FOR THE REACTION PI- P ---> ETA N FROM 1171-MEV/C TO 2267-MEV/C AND A PARTIAL WAVE ANALYSIS OF THIS REACTION IN THE RESONANCE REGION

Baker, R.D. ; Brown, Robert M. ; Clark, A.G. ; et al.
Nucl.Phys.B 156 (1979) 93-110, 1979.
Inspire Record 146768 DOI 10.17182/hepdata.34678

Polarized cross sections for the reaction π − p → η n have been measured at 12 incident momenta between 1171 and 2267 MeV/ c . The data show that the polarization is small in the forward direction and there is a general trend for it to be large and positive near cos θ ∗ = 0.2 . These are the first published results on polarization effects in this channel in the resonance region. An energy-dependent partial-wave analysis has been performed and the couplings and branching fractions for decays of nucleon resonances to this channel are presented.

12 data tables
Table 1

No description provided.

Table 2

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Table 3

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DIFFERENTIAL CROSS-SECTIONS FOR THE REACTION PI- P ---> ETA N BETWEEN 724-MEV/C AND 2723-MEV/C

Brown, Robert M. ; Clark, A.G. ; Duke, P.J. ; et al.
Nucl.Phys.B 153 (1979) 89-111, 1979.
Inspire Record 146579 DOI 10.17182/hepdata.34682

Differential cross sections for the reaction π − p→ η n at 20 incident pion momenta between 724 and 2723 MeV/ c are presented. The results are compared with previous measurements. The data show clear evidence of non-zero couplings of this channel to known I = 1 2 , S = 0 baryon resonances with masses up to 2000 MeV/ c 2 .

22 data tables
Table 1

No description provided.

Table 2

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Table 3

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$K^- p$ and $\bar{p} p$ Elastic Scattering at 10.1-{GeV}/$c$

Berglund, A. ; Buran, T. ; Carlson, P.J. ; et al.
Nucl.Phys.B 176 (1980) 346-354, 1980.
Inspire Record 133174 DOI 10.17182/hepdata.34457

The differential cross sections for K − p and p p elastic scattering have been measured over the range of four-momentum transfer squared 0.18<− t <3.3 (GeV/ c ) 2 . The K − p data decrease smoothly as a function of − t , whereas, the p p data shows a break at − t = 0.6 (GeV/ c ) 2 followed by a fast drop to − t ≅ 1.6 (GeV/ c ) 2 where the differential cross section levels off and stays constant out to − t = 3 (GeV/ c ) 2 .

2 data tables
Table 1

No description provided.

Table 2

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