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Magnetic Form Factor of the Deuteron

Auffret, S. ; Cavedon, J.M. ; Clemens, J.C. ; et al.

Phys.Rev.Lett. 54 (1985) 649-652, 1985.

Inspire Record 214266 DOI 10.17182/hepdata.20337

We have measured the deuteron magnetic form factor B(q2) for values of the momentum transfer squared between 7 and 28 fm−2. The data are compared with relativistic and nonrelativistic predictions including meson-exchange-current contributions. Significant disagreement is found for large momentum transfers.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Intermediate Mass Dimuon Events at the {CERN} $p \bar{p}$ Collider at $\sqrt{s}=540$-{GeV}

The UA1 collaboration Arnison, G. ; Allkofer, O.C. ; Astbury, A. ; et al.

Phys.Lett.B 155 (1985) 442-456, 1985.

Inspire Record 213203 DOI 10.17182/hepdata.49630

We report the observation of 21 dimuon events at the CERN p p Collider with the UA1 detector. The events range in invariant dimuon mass from 2 to 22 GeV / c 2 . The properties of these events are given. The bulk of the events are consistent with heavy-flavour production (mainly b b ) with a few candidates for Drell-Yan production. There remain a few events which are difficult to interpret in terms of these processes, in particular two events with isolated, like-sign muons.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

CHARGED PARTICLE MULTIPLICITIES IN PI-, K- AND ANTI-P INTERACTIONS WITH NUCLEI AT 40-GEV/C

The RISK collaboration Boos, E.G. ; Mosienko, A.M. ; Pokrovsky, N.A. ; et al.

Z.Phys.C 26 (1984) 43-52, 1984.

Inspire Record 214970 DOI 10.17182/hepdata.22350

Interactions of 40 GeV/c πp-,K− and$\bar p$ on Li, C, S, Cu, CsI and Pb were studied with the RISK-streamer chamber spectrometer. We present multiplicities of negatively charged particles, as well as of protons, and the correlations between them. The normalized mean multiplicity of negative particles,R−, depends on$\bar v$, the average number of inelastic collisions as$R^ -= (0.73 \pm 0.04) + (0.34 \pm 0.02)\bar v$. The dependence of the normalized dispersion of negative particles,D−/<N−>, on the number of protons favours independent collision models and contradicts the coherent tube picture. The excess of fast positive particles behaves asA0.4 and shows, for the heavier nuclei, a clear correlation with identified protons.

2 data tables

Table 1

AVERAGE MULTIPLICITIES OF ALL CHARGED PARTICLES.

Table 2

AVERAGE MULTIPLICITIES OF ALL NEGATIVELY CHARGED PARTICLES.

New Results on the Reaction $e^+ e^- \to \mu^+ \mu^-$ at $\sqrt{s}=29$-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.

Phys.Rev.D 31 (1985) 2352, 1985.

Inspire Record 212767 DOI 10.17182/hepdata.3935

We have measured the process e+e−→μ+μ− at √s =29 GeV using the High Resolution Spectrometer at SLAC PEP. The forward-backward charge asymmetry is Aμμ=-(4.9±1.5±0.5)% based on 5057 events. A subsample of 3488 μ+μ− events in the angular range ‖cosθ‖<0.55 gives a cross-section ratio of Rμμ=0.990±0.017±0.030. The resulting couplings of the weak neutral current are gaegaμ=0.208±0.064± 0.021 and gvegvμ=0.027 ±0.051±0.089. The QED cutoff parameters are Λ+>170 GeV and Λ−>146 GeV at 95% C.L.

4 data tables

Table 1

Corrected for acceptance and O(alpha**3) QED radiation. Numerical values taken from SUGANO-ANL-HEP-CP-84-90.

Table 2

Forward-backward asymmetry based on fit to angular distribution. Result is given combined with earlier data from BENDER et al.

Table 3

No description provided.

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Search for narrow structure in proton‐antiproton annihilation cross sections from 1900 to 1960 MeV

Lowenstein, D.I. ; Pealsee, D.C. ; Miller, R.J. ; et al.

Phys.Lett.B 158 (1985) 505-510, 1985.

Inspire Record 221435 DOI 10.17182/hepdata.30389

The p̄p annihilation cross section has been measured with good resolution (∼2 MeV rms) in the mass range 1900–1960 MeV. No narrow structures are seen, the 90% confidence level upper limit being 8–12 mb‐MeV for the integrated area of a resonance in this mass range. However, we do not rule out a very narrow bump‐dip structure seen in an earlier experiment in the 1935–1941 MeV mass interval. The data also do not support the existence of a broad structure previously reported at 1937 MeV.

1 data table

Table 1

Fit of form A + B/D gives A = 8.5 +- 2.5mb and B = 40.7 +- 1.3mb in the mass range 1900 to 1960 MeV.

FRAGMENTATION INTO STRANGE PARTICLES IN HIGH-ENERGY NEUTRINO P, neutrino N, ANTI-NEUTRINO P AND ANTI-NEUTRINO N INTERACTIONS

The AMSTERDAM-BERGEN-BOLOGNA-PADUA-PISA-SACLAY-TURIN collaboration Allasia, D. ; Angelini, C. ; Baldini, A. ; et al.

Phys.Lett.B 154 (1985) 231-235, 1985.

Inspire Record 218756 DOI 10.17182/hepdata.30415

The fragmentation of the hadronic system into Λ, Σ(1385), K ) and K ∗ (892) in deep-inelastic charged-current interactions of high energy neutrinos and antineutrinos with proton and neutron is analyzed. The results obtained for the production of these particles from the various initial states are compared with each other and with the predictions of the Lund fragmentation model. This comparison shows that a spectator diquark does not fragment as a whole in a fraction of the interactions. The role of the sea quarks in the baryon formation process is underlined. Strange vector and pseudoscalar mesons are likely to be produced at similar rates.

3 data tables

Table 1

No description provided.

Table 2

SIG(C=LAMBDA) denotes the inclusive LAMBDA production in the same reaction.

Table 3

SIG(C=KS) denotes the inclusive KS production in the same reaction.

Measurements of Interaction Cross-Sections and Radii of He Isotopes

Tanihata, I. ; Hamagaki, H. ; Hashimoto, O. ; et al.

Phys.Lett.B 160 (1985) 380-384, 1985.

Inspire Record 212823 DOI 10.17182/hepdata.30351

Secondary beams of 3 He, 4 He, 6 He, and 8 He were produced through the projectile fragmentation of an 800 MeV/nucleon 11 B primary beam. Interaction cross sections ( σ I ) of all He isotopes of 790 MeV/nucleon on Be, C, and Al targets were measured by a transmission-type experiment. The interaction nuclear radii of He isotopes R I ( He ) = ( σ I π ) 1 2 − R I ( T ) where R I ( T ) is the radius of the target nucleus, have been deduced to be R I ( 3 He ) = 1.59 ± 0.06 fm , R I ( 4 He ) = 1.40 ± 0.05 fm , R I ( 6 He ) = 2.21 ± 0.06 fm , and R I ( 8 He ) = 2.52 ± 0.06 fm .

1 data table

Table 1

No description provided.

ANALYSIS OF THE REACTION PI- P ---> PI0 ETA N AT 40-GEV/C BEAM MOMENTUM.

The SERPUKHOV-CERN collaboration Apel, W.D. ; Augenstein, K.H. ; Bertolucci, E. ; et al.

Yad.Fiz. 41 (1985) 126-136, 1985.

Inspire Record 218766 DOI 10.17182/hepdata.2594

None

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the Reaction $e^+ e^- \to \tau^+ \tau^-$ at $\sqrt{s}=29$-{GeV}

Gan, K.K. ; Beltrami, I. ; Bylsma, B.G. ; et al.

Phys.Lett.B 153 (1985) 116-120, 1985.

Inspire Record 212773 DOI 10.17182/hepdata.6571

The reaction e + e − → τ + τ − has been measured using the high resolution spectrometer at PEP. The angular distribution shows a forward-backward asymmetry of −(6.1±2.3±0.5)%, corresponding to an axial-vector coupling if g a τ g a e = 0.28 ±0.11± 0.03, in good agreement with the standard model of electroweak interactions. The measured cross section yields ifR ττ = 1.10± 0.03±0.04, consistent with QED and giving QED cutoff parameters of Λ + >92 GeV and Λ − >246 GeV at 95% C.L.

4 data tables

Table 1

Comparison of total tau pair cross section with O(alpha**3) QED prediction.

Table 2

Corrected for acceptance backgraound, and O(alpha**3) radiative effects.

Table 3

Forward-backward asymmetry based on fit to angular distributions.

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