Yamamoto, K.
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Measurement of Polarized Target Asymmetry on $\gamma n \to \pi^- p$ Around the Second Resonance Region

Fujii, K. ; Hayashii, H. ; Iwata, S. ; et al.
Nucl.Phys.B 187 (1981) 53-70, 1981.
Inspire Record 156223 DOI 10.17182/hepdata.34260

The polarized target asymmetry for γ n→ π − p was measured over the second resonance region from 0.55 to 0.9 GeV at pion c.m. angles between 60° and 120°. A double-arm spectrometer was used with a deuterated butanol target to detect both the pion and the proton, thus considerably improving the data quality. Including the new data in the amplitude analysis, the radiative decay widths of three resonances were determined more accurately than before. The results are compared with various quark models.

8 data tables
Table 1

PHOTON ENERGY IS IN THE NEUTRON REST FRAME.

Table 2

PHOTON ENERGY IS IN THE NEUTRON REST FRAME.

Table 3

PHOTON ENERGY IS IN THE NEUTRON REST FRAME.

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Diffractive Production of 3 $\pi$ States at 63-{GeV} and 94-{GeV}

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Nucl.Phys.B 182 (1981) 269-336, 1981.
Inspire Record 156369 DOI 10.17182/hepdata.34314

Diffractive production of the 3 π system has been studied at 63 and 94 GeV using a two magnet spectrometer with high, uniform acceptance. The total number of events used in the analysis is ∼600 000. The A 2 meson is shown to be diffractively produced. The existence of a resonant component in both the 1 + and 2 − enhancements is established and resonance parameters for the corresponding A 1 and A 3 mesons are given. There are several indications in the data of states which would correspond to radial excitations in the quark model.

4 data tables
Table 1

SEE C. DAUM ET AL., PL 89B, 276 (1980) (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+486> RED = 486 </a>), AND THE RECORD (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+420> RED = 420 </a>) OF THE GENEVA CONFERENCE PREPRINT, B. ALPER ET AL. (1979).

Table 2

SEE C. DAUM ET AL., PL 89B, 281 (1980) (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+487> RED = 487 </a>), AND THE RECORD (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+419> RED = 419 </a>) OF THE GENEVA CONFERENCE PREPRINT, G. THOMPSON ET AL. (1979).

Table 3

SEE C. DAUM ET AL., PL 89B, 285 (1980) (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+488> RED = 488 </a>), AND THE RECORD (<a href=http://durpdg.dur.ac.uk/scripts/reacsearch.csh/TESTREAC/red+421> RED = 421 </a>) OF THE GENEVA CONFERENCE PREPRINT, B. ALPER ET AL. (1979).

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Study of the Charge Exchange Reactions $\pi^- p \to (\pi^0$, $\eta$, $\eta^\prime$) $n$ at 63-{GeV}

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Z.Phys.C 8 (1981) 95, 1981.
Inspire Record 156266 DOI 10.17182/hepdata.49658

None

4 data tables
Table 1

INCLUDING SYSTEMATIC ERRORS.

Table 2

STATISTICAL ERRORS ONLY.

Table 3

STATISTICAL ERRORS ONLY.

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Measurement of the Polarization in Large Angle $\pi^- P$ Elastic Scattering at 2.93-{GeV}/c and 3.25-{GeV}/c

Auer, I.P. ; Bridges, D. ; Droege, T. ; et al.
Phys.Rev.D 24 (1981) 1771-1784, 1981.
Inspire Record 172691 DOI 10.17182/hepdata.24055

We have measured the polarization for elastic scattering in the reaction π−p→π−p at 2.93 and 3.25 GeV/c using a polarized proton target and multiwire proportional chambers (MWPC's) with emphasis on large-angle scattering. Events were selected by fast scintillation-counter logic. Beam trajectories were measured with four MWPC's and the scattered-particle angles were measured with one or two MWPC's; elastic events were determined by coplanarity and angle-angle correlations. The polarization is in agreement with previous measurements below |t|=2.0 (GeV/c)2, and crosses from negative to positive near the secondary dip in the differential cross section dσdt. In the backward region, an energy dependence appears with the polarization being large and negative at 2.93 GeV/c and consistent with zero at 3.25 GeV/c.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Study of Particle Ratios in Single and Double Pion Production in $P P$ Interactions at 405-{GeV}/c

Suzuki, A. ; Fukawa, M. ; Kichimi, H. ; et al.
Phys.Rev.D 24 (1981) 605-611, 1981.
Inspire Record 171446 DOI 10.17182/hepdata.4382

We present results on inclusive study of particle production ratios in 405-GeV/c pp interactions from a Fermilab experiment using the 30-in. hydrogen bubble chamber. Single- and double-pion ratios π+π−, π+π−π−π−, and π+π−π+π+ as a function of the Feynman variable x are presented. From these analyses, it is shown that the quark-recombination picture seems to work well for particle production in the fragmentation region. The data on π+π− ratios in association with a leading π± or Λ are compared with each other and also with the π+π−π−π− ratio. These results further support a prediction of the quark-recombination model.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Lepton Pair Production and Search for a New Heavy Lepton in $e^+ e^-$ Annihilation

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 99 (1981) 489-494, 1981.
Inspire Record 164302 DOI 10.17182/hepdata.27110

We have measured the reaction ee → μμ and ee → ττ at center of mass energies from 9.4 to 31.6 GeV. The production cross sections are in agreement with the predictions of quantum electrodynamics, resulting in cutoff parameter limits of 70–100 GeV at 95% c.l. The branching ratio for τ → μν ν has been determined as [1.78 ± 2.0 (statist.) ± 1.8(syst.)]% The existence of a new sequential heavy lepton with a mass <14.5 GeV is excluded at 95% c.l.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


RECOIL PROTON POLARIZATION OF PROTON COMPTON SCATTERING IN THE RESONANCE REGION

Wada, Y. ; Kato, S. ; Miyachi, T. ; et al.
Nuovo Cim.A 63 (1981) 57-70, 1981.
Inspire Record 170488 DOI 10.17182/hepdata.37543

The recoil proton polarization of proton Compton scattering (γp→γp) was measured in the photon energy range from 500 MeV to 1000 MeV atθ∗=100° and from 400MeV to 800 MeV atθ∗=130°. A recoil proton and a scattered photon were detected in coincidence with a magnetic spectrometer and a photon detector. The recoil proton polarization was measured with a carbon polarimeter. The results are compared with a phenomenological analysis based on an isobar model and a dynamical analysis based on the dispersion relation.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Measurement of the Real to Imaginary Ratio of the $\bar{P} P$ Forward Amplitude at Beam Momenta Between 400-{GeV}/c and 730-{MeV}/c

Iwasaki, H. ; Aihara, H. ; Chiba, J. ; et al.
Phys.Lett.B 103 (1981) 247-250, 1981.
Inspire Record 170359 DOI 10.17182/hepdata.31184

Differential cross sections of p p forward elastic scattering were measured between 400 and 730 MeV/ c , and the real-to-imaginary ratio, ϱ, of the forward amplitude was deduced. We found that ρ increases from ∼ 0.1 to ∼ 0.4 in this momentum range. A dispersion-relation analysis shows the existence of a pole-like structure in the real part of the p p amplitude near threshold.

1 data table
Table 1

REAL/IMAG RATIO OF FORWARD AMPLITUDE DETERMINED FROM FIT TO COULOMB-NUCLEARINTERFERENCE.


Observation of a $K \bar{K}$ Enhancement at 1.85-{GeV} in the Reaction $K^- P \to K \bar{K} \Lambda$ at 8.25-{GeV}/c

The BIRMINGHAM-CERN-GLASGOW-MICHIGAN STATE-PARIS collaboration Al- Harran, S. ; Amirzadeh, J. ; Baubillier, M. ; et al.
Phys.Lett.B 101 (1981) 357-360, 1981.
Inspire Record 170589 DOI 10.17182/hepdata.31206

In a high statistics ( ∼150 eV μb ) bubble chamber experiment on K − p interactions at 8.25 GeV c , the study of the reaction K − p → KK Λ provides evidence for an enhancement in the KK system with a mass of (1850 ± 10) MeV and a width of (80 −30 +40 ) MeV. Its possible identification with the missing isosinglet of the 3 − nonet is discussed. A K ∗ K decay mode is also observed.

1 data table
Table 1

No description provided.


PRODUCTION OF F-prime (1520) IN 8.25-GEV/C K- P INTERACTIONS

The BIRMINGHAM-CERN-GLASGOW-MICHIGAN STATE-PARIS collaboration Al- Harran, S. ; Baubillier, M. ; Bloodworth, I.J. ; et al.
Nucl.Phys.B 191 (1981) 26-38, 1981.
Inspire Record 172450 DOI 10.17182/hepdata.34233

We present results for the hypercharge exchange reaction K − p→f' λ from a high statistics experiment at 8.25 GeV/ c using the CERN 2m HBC. The total and differential cross sections have been measured; the polarisation of the Λ hyperon and the f' density matrix elements have been calculated as functions of momentum transfer. We also present detailed information on the relative strength of the natural and unnatural parity exchange contributions to the production mechanism.

5 data tables
Table 1

D-WAVE RELATIVISTIC BREIT-WIGNER RESONANCE PLUS POLYNOMIAL BACKGROUND FIT.

Table 2

FITTED FOR INDIVIDUAL TP BINS.

Table 3

No description provided.

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