Chang, C.Y.
Muon production
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A STUDY OF THE STRONG INTERACTION FORM-FACTORS FOR K0(L) ---> pi mu neutrino AND K0(L) ---> pi electron neutrino

Dally, E. ; Innocenti, P. ; Seppi, E. ; et al.
Phys.Lett.B 41 (1972) 647-651, 1972.
Inspire Record 74541 DOI 10.17182/hepdata.28214

We have extracted the strong interaction form factors from K o e3 and K o μ3 data of our previously reported K o L experiment in a manner which does not assume an explicit q 2 = ( p K − p π ) 2 dependence. We present the unparameterized form factors ƒ + (q 2 ) from the K o L → πeν and K o L → πμν modes and ƒ o (q 2 ) and ξ ( q 2 ) from the K o L → πμν data. A comparison of these unparameterized results is made with the results of the Dalitz plot analyses.

1 data table
Table 1

The conventional form factor f+ is studied.


A Search for Longlived Neutral Heavy Leptons in 400 GeV/c Proton Interactions

Bechis, D.J. ; Chang, C.Y. ; Dombeck, T.W. ; et al.
Phys.Rev.Lett. 40 (1978) 602-604, 1978.
Inspire Record 6478 DOI 10.17182/hepdata.37888

We report a null search for neutral heavy leptons produced unaccompanied by muons in 400-GeV/c proton-nucleon collisions in a magnetized beam dump and decaying in vacuum downstream. The upper limit on σB for L0's with Feynman x≳0.2 and θlab≲10 mrad with branching ratio B into two charged particles is σB≲2.8×10−35 cm2/nucleon at the 90% confidence level for masses below 1.0 GeV/c2 and lifetimes between 10−10 and 10−8 sec.

1 data table
Table 1

No description provided.


Measurement of the Relative Total Hadronic Cross-section R at {PETRA}

The Aachen-DESY-Annecy(LAPP)-MIT-NIKHEF-Beijing collaboration Barber, D. ; Becker, U. ; Boehm, A. ; et al.
Phys.Rev.Lett. 42 (1979) 1113, 1979.
Inspire Record 140059 DOI 10.17182/hepdata.3235

We report the first measurement of the ratio R=(σe+e−→hadrons)(σe+e−→μ+μ−) (with negligible τ-lepton contribution) at a center-of-mass energy s=13 GeV and s=17 GeV, from the just finished electron-positron colliding-beam facility PETRA. The detector, MARK-J, has an approximately 4π solid angle and measures γ, e, μ, and charged and neutral hadrons simultaneously. Our results yield R(s=17 GeV)=4.9±0.6 (statistical) ±0.7 (systematic error), and R(s=13 GeV)=4.6±0.5 (statistical) ±0.7 (systematic error). The ratio R(s=17 GeV)R(s=13 GeV) is 1.08±0.18.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


INCLUSIVE PRODUCTION OF K*+- (890) AND SIGMA+- (1385) RESONANCES IN ANTI-P P INTERACTIONS AT 14.75-GEV/C

Canter, J. ; Chang, C.C ; Dao, F.T. ; et al.
Phys.Rev.D 20 (1979) 1029-1036, 1979.
Inspire Record 144992 DOI 10.17182/hepdata.24210

The inclusive and semi-inclusive cross sections for K*±(890) and Σ±(1385) resonances are determined in p¯p interactions at 14.75 GeV/c. They account for a large fraction of the KS0 and Λ0 produced. The K*-resonance production also affects the low-pT2 distribution of inclusive KS0. The x distributions of the resonance production are studied in terms of a simple quark-recombination model.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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A Test of Universality of Charged Leptons

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 43 (1979) 1915, 1979.
Inspire Record 142012 DOI 10.17182/hepdata.20759

Measurements of the reactions e++e−→e++e−, μ++μ−, and τ++τ− at PETRA energies (s12=13,17,27.4,30 and 31.6 GeV) are reported. The results show that these reactions agree well with the predictions of quantum electrodynamics thus determining that all the known charged leptons are pointlike particles to a distance < × 10−16 cm.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


EXPERIMENTAL STUDY OF HEAVY CHARGED LEPTONS AT PETRA

Barber, D.P. ; Becker, U. ; Bei, G.D. ; et al.
Phys.Rev.Lett. 45 (1980) 1904-1907, 1980.
Inspire Record 158858 DOI 10.17182/hepdata.20675

Data from the MARK-J detector on the reactions e+e−→μ+μ−, τ+τ− in the center-of-mass energy range from 12 to 36.7 GeV are presented. The μ, τ radii are shown to be <10−16 cm. A search has been made for the production of a new heavy lepton and for the production of spin-0 supersymmetric partners of the muon. 95%-confidence-level lower limits of 16 GeV for the mass of a new charged heavy lepton and 15 GeV for the mass of the scalar partners of the muon are obtained.

1 data table
Table 1

No description provided.


INCLUSIVE MUON PRODUCTION AT PETRA ENERGIES

The Pluto collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Rev.Lett. 45 (1980) 1533-1537, 1980.
Inspire Record 153812 DOI 10.17182/hepdata.20692

In this Letter, a measurement of inclusive muon production (pμ>2 GeV/c) in e+e− annihilation into hadrons at center-of-mass energies from s=12 to 31.6 GeV is reported. The results agree with the expected semileptonic decays from charmed and bottom mesons.

2 data tables
Table 1

MUONS PER HADRONIC EVENT.

Table 2

INVARIANT CROSS SECTION, ASSUMING HADRONIC CROSS SECTION HAS R VALUE OF 3.9 +- 0.5.


Unique Solution for the Weak Neutral Current Coupling Constants in Purely Leptonic Interactions

The Mark-J collaboration Barber, D.P. ; Becker, U. ; Berghogff, G. ; et al.
Phys.Lett.B 95 (1980) 149-153, 1980.
Inspire Record 154136 DOI 10.17182/hepdata.6235

By combining results from the MARK-J at PETRA on Bhabha scattering, μ + μ - and τ + τ - production with recent world data from neutrino-electron scattering experiments, we determine unique values for the leptonic weak neutral current coupling constants g V and g A in the framework of electroweak models containing a single Z 0 . In contrast to previous analyses, we only use data from purely leptonic interactions, and therefore avoid the inherent uncertainties resulting from the use of hadronic targets. From the MARK-J data alone in the context of the standard SU(2) ⊗ U (1) model of Glashow, Weinberg and Salam, we find sin 2 θ W =0.24±0.11.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Experimental Test of Electroweak Effects at {PETRA} Energies

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Z.Phys.C 7 (1981) 289, 1981.
Inspire Record 156660 DOI 10.17182/hepdata.13818

The differential cross sections for Bhabha scattering and μ pair production, and the total τ pair cross section as measured by the PLUTO detector at PETRA, have been analyzed to extract information on the weak interaction of leptons. The data are compared with unified gauge theories. Since the observed electroweak effects are still consistent with zero (within errors) we can set experimental limits on neutral current parameters atQ2 values of 950 GeV2. In the framework of the standard SU(2)×U(1) model we find sin2Θw<0.52(95% c.l.). In the context of general singleZo models we can excludeZo masses of less than 40 GeV.

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.