Lynch, H.L.
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On $K_L$ - $K_S$ Regeneration in Copper

Bohm, A. ; Darriulat, P. ; Grosso, C. ; et al.
Phys.Lett.B 27 (1968) 594-598, 1968.
Inspire Record 1374884 DOI 10.17182/hepdata.69210

The transmission regeneration amplitude after a thick copper block has been measured. The quantity {∣ƒ(0)- overlineƒ(0)∣ }/{k} varies from 20.0 $\pm$ 1.4 mb at 2.75 GeV/c to 13.6 $\pm$ 1.2 mb at 7.25 GeV/c. Results are in agreement with optical model calculations in which real and imaginary parts of the amplitudes for single nucleon scattering are determined from forward dispersion relations and total cross-sections.

1 data table
Table 1

Regeneration amplitude.


Pion production and elastic scattering in anti-proton-proton collisions at 6.94 bev/c

Ferbel, T. ; Johnson, J.A. ; Kraybill, H.L. ; et al.
Phys.Rev. 173 (1968) 1307-1314, 1968.
Inspire Record 55957 DOI 10.17182/hepdata.26499

We have studied nonstrange p¯−p interactions observed in 7000 pictures of the 80-in. Brookhaven National Laboratory hydrogen bubble chamber exposed to an antiproton beam with a momentum of 6.94 BeVc. The total cross section was measured to be 58.7±2.8 mb, and the elastic interaction cross section 14.2±1.2 mb. The elastic differential cross section for four-momentum transfers (−t)≤0.3 (BeVc)2 is well described by the exponential form dσeldt=(dσdt)t=0ebt, where b=13.1±1.1 (BeVc)−2. The single-pion production cross section is 4.0±0.9 mb. This channel proceeds 70% through resonance formation. N*(1238) isobar and anti-isobar formation dominates pion production in four- and six-pronged events; the double-isobar formation cross section in the final state pπ+p¯π− is 1.35±0.2 mb. Isobar production was observed to be consistent with the predictions of a dominant one-particle-exchange process. The pion-annihilation process, which has a cross section of 25±5 mb, shows substantial pion resonance formation.

1 data table
Table 1

'1'. '2'.


Cross sections for p p ---> d rho+ from 4.0 to 12.3 gev/c and a search for the delta+

Anderson, H.L. ; Dixit, M. ; Evans, H.J. ; et al.
Phys.Rev.Lett. 26 (1971) 108-112, 1971.
Inspire Record 69063 DOI 10.17182/hepdata.21629

Forward differential cross sections for isospin-1 bosons produced in p+p→d+x+ were measured using a deuteron missing-mass spectrometer at a small angle between 4.0- and 12.3−GeVc incident momentum. Differential cross sections for π+ and ρ+ were extracted from the spectra using phase-space backgrounds. They range from 10.4 to 0.4 μb/sr for π+ and from 1.4 to 0.3 μb/sr for ρ+. A bump near 6 GeVc appears in both dπ and dρ channels. No clear evidence is seen for higher-mass bosons. The possible δ+ cross sections average less than 0.01 μb/sr.

3 data tables
Table 1

TECHNIQUE USED...ELECTRONIC. TABLE 1.

Table 2

TECHNIQUE USED...MISSING MASS. BREIT WIGNER USED WITH FIXED WIDTH (150 MEV) AND VARIABLE MASS (LATTER VARIED WITH MOMENTA FROM 715 TO 765 MEV). 6 PERCENT NORMALIZATION ERROR; 20 PERCENT FROM BREIT WIGNER FIT. TABLE 1.

Table 3

TECHNIQUE USED...MISSING MASS. CROSS-SECTIONS CORRESPOND TO VERY NARROW DELTA (962).


Production of high transverse momentum particles in p p collisions in the central region at the CERN ISR

The British-Scandinavian ISR collaboration Alper, B. ; Boggild, H. ; Jarlskog, G. ; et al.
Phys.Lett.B 44 (1973) 521-526, 1973.
Inspire Record 85256 DOI 10.17182/hepdata.28095

The inclusive production al all charged particles of transverse momentum p T between 1.5 and 4.4 GeV/ c at centre of mass angles 90° and 59.4° from p-p-collisions with √ s = 44 and 53 GeV has been measured. No strong energy dependence is observed for these transverse momenta.

6 data tables
Table 1

Errors are statistical only.

Table 2

Errors are statistical only.

Table 3

Errors are statistical only.

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Measurements of the differential cross-section of the reaction p p ---> d pi+ from 3.0 to 5.0 gev/c

Anderson, H.L. ; Larson, D.A. ; Myrianthopoulos, L.C. ; et al.
Phys.Rev.D 9 (1974) 580-596, 1974.
Inspire Record 93111 DOI 10.17182/hepdata.21941

A measurement of the complete differential cross section for the reaction pp→dπ+ at 3.00, 3.20, 3.43, 3.65, 3.83, 4.00, 4.20, and 5.05 GeVc incident proton momentum has been made in an attempt to establish the role of the Δ (1950) in this region. The data show that the previously observed enhancement in the forward cross section between 3 and 4 GeVc due to this isobar is an effect which damps out quickly as the production angle departs from zero degrees, in contrast with the well-known enhancement at 1.35 GeVc, which is evident at all angles. In particular, the one-pion-exchange model is in poor agreement with the extended set of data. A detailed description is given of a novel proportional-wire-chamber system which facilitated the selection of this rather rare reaction from a very high competing background.

3 data tables
Table 1

Axis error includes +- 6/6 contribution.

Table 2

Axis error includes +- 6/6 contribution.

Table 3

No description provided.


The Discovery of a Second Narrow Resonance in e+ e- Annihilation

Abrams, G.S. ; Briggs, D. ; Chinowsky, William ; et al.
Phys.Rev.Lett. 33 (1974) 1453-1455, 1976.
Inspire Record 91611 DOI 10.17182/hepdata.21287

We have observed a second sharp peak in the cross section for e+e−→hadrons at a center-of-mass energy of 3.695±0.004 GeV. The upper limit of the full width at half-maximum is 2.7 MeV.

1 data table
Table 1

No description provided.


Study of K+ pi- Scattering in the Reaction K+ p ---> K+ pi- Delta++ at 12-GeV/c

Matison, M.J. ; Barbaro-Galtieri, A. ; Alston-Garnjost, M. ; et al.
Phys.Rev.D 9 (1974) 1872, 1974.
Inspire Record 94524 DOI 10.17182/hepdata.21979

We have studied K+π− elastic scattering in the reaction K+p→K+π−Δ++ at 12 GeVc and in the Kπ mass interval 800 to 1000 MeV. We have performed a partial-wave analysis in this Kπ mass region, dominated by the p-wave resonance K*(890), in order to obtain information about the s-wave amplitude. We have extrapolated the K+π− moments, the total cross section, and p-wave cross section to the pion pole. The p-wave cross section is close to the unitarity limit and can be described by a Breit-Wigner resonance form, with parameters M=896±2 MeV and Γ=47±3 MeV. We then perform an energy-independent phase-shift analysis of the extrapolated moments and total cross section using this Breit-Wigner form for the p wave and a previously determined small negative phase shift for the I=32s wave. For the I=12s-wave phase shift we find the so called "down" solution, which has a phase shift that rises slowly from 20° at M(Kπ)=800 MeV to 60° at M(Kπ)=1000 MeV. The energy dependence of this phase shift is well described by an effective range form, with a scattering length a01=−0.33±0.05 F. The so-called "up" solution is eliminated or has large χ2 everywhere except for two overlapping mass intervals at M(Kπ)=890 and 900 MeV. However, due to limited statistics, we expect two solutions for the s wave very near the mass where the p wave is resonant. We then perform an energy-dependent partial-wave analysis and find again no evidence for an s-wave resonance although, due to limited statistics, we could not exclude one at 890 MeV with Γ<7 MeV.

2 data tables
Table 1

Extrapolation.

Table 2

Extrapolation. Initial K+ PI- system in P-wave state.


Spin Parity Analysis of the B Meson

Chung, S.U. ; Protopopescu, S.D. ; Lynch, G.R. ; et al.
Phys.Rev.D 11 (1975) 2426, 1975.
Inspire Record 91530 DOI 10.17182/hepdata.24885

We have done a JP analysis of the low-mass π+ω system, using the reaction π+p→π+ωp at 7.1 GeV/c. We find that the B resonance cannot be JP=0− and must belong to the unnatural-parity series (1+, 2−, 3+,...), regardless of the amount of interference between the B and the background. If we assume that the B does not interfere with the background, we find that all JP states for the resonance are rejected except for 1+. Even if interference effects are allowed in the analysis, a good fit with reasonable parameters is obtained only with the 1+ hypothesis for the B meson. In an appendix, we give relevant theoretical formulas appropriate for a πω system with any number of spin-parity states and arbitrary degrees of interference among them.

1 data table
Table 1

TAKING INTO ACCOUNT 0- AND 1+ SMOOTH BACKGROUND UNDER THE B MESON. EVENTS WITH 1.08 < M(PI+ OMEGA) < 1.38 GEV.


Measurement of e+ e- ---> e+ e- and e+ e- ---> mu+ mu- at SPEAR

Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 34 (1975) 233, 1975.
Inspire Record 91755 DOI 10.17182/hepdata.21210

The reactions e+e−→e+e− and e+e−→μ+μ− have been measured at center-of-mass energies 3.0, 3.8, and 4.8 GeV and production angles of 50°<θ<130° over all azimuthal angles. Agreement with quantum electrodynamics is excellent. New limits for cutoff parameters in quantum-electrodynamic-breakdown models are given.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Discovery of a Narrow Resonance in $e^+ e^-$ Annihilation

The SLAC-SP-017 collaboration Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 33 (1974) 1406-1408, 1974.
Inspire Record 91761 DOI 10.17182/hepdata.21247

We have observed a very sharp peak in the cross section for e+e−→hadrons, e+e−, and possibly μ+μ− at a center-of-mass energy of 3.105±0.003 GeV. The upper limit to the full width at half-maximum is 1.3 MeV.

1 data table
Table 1

No description provided.