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Experimental Proof of the Existence of the A1 Meson

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.

Phys.Lett.B 89 (1980) 281-284, 1980.

Inspire Record 143044 DOI 10.17182/hepdata.27272

In partial wave analyses of the ( π − π − π + ) system, substantial shape changes of the 1 + S ( ϱπ ) intensity as a function of t , and relative phase changes of ≈ 90°, provide compelling evidence for a resonant A 1 of mass ≈ 1280 MeV and width ≈ 300 MeV.

1 data table

Table 1

No description provided.

3 $\pi$ Resonances in 2- Partial Waves

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.

Phys.Lett.B 89 (1980) 285-289, 1980.

Inspire Record 143045 DOI 10.17182/hepdata.27275

The J PC = 2 −+ partial wave intensities and their large phase changes prove the resonant nature of the A 3 meson (mass ≈ 1670 MeV, width ≈ 210 MeV). The decay modes are f 0 π , ϱ 0 π , and ϵ 0 π . Evidence is found for a further 2 − enhancement.

1 data table

Table 1

No description provided.

HIGH STATISTICS INCLUSIVE phi MESON PRODUCTION AT SPS ENERGIES

The ACCMOR collaboration Dijkstra, H. ; Bailey, R. ; Belau, E. ; et al.

Z.Phys.C 31 (1986) 375-389, 1986.

Inspire Record 18260 DOI 10.17182/hepdata.15894

Inclusive ϕ meson production has been measured for 100 GeV/c and 200 GeV/c incident π−,$\bar p$ andK−, and for 120 GeV/c and 200 GeV/c incident π+,p andK+, using a Be target. A total of 630,000 ϕ mesons has been recorded in the kinematic range 0<xF<0.4. Presented are the differential cross sectionsdσ/dxF anddσ/dpT2. The longitudinal momentum distributions show that the strange valence quarks of the incidentK mesons play an important role in ϕ meson production, even at smallxF. The decay angular distribution of the ϕ meson is evaluated in the Gottfried-Jackson frame and is expressed in the elements of the density matrix. There is a small but significant cos2θGJ dependence for smallpT, which decreases for increasingpT.

34 data tables

Table 1

Note that the data is plotted in fig. 5 a factor 5 too large. The numbers here are correct.

Table 2

Note that the data is plotted in fig 5 a factor of 5 too large. The numbers here are correct.

Table 3

Note that the data is plotted in fig. 5 a factor of 5 too large. CT = The numbers here are correct.

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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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RESULTS ON LAMBDA(c)+, D(s)+, D0 AND D+ PRODUCTION PROPERTIES IN 230-GeV/c pi- Cu INTERACTIONS FROM THE NA32 EXPERIMENT

The ACCMOR collaboration Barlag, S. ; Becker, H. ; Bohringer, T. ; et al.

CERN-EP/88-104, 1988.

Inspire Record 264995 DOI 10.17182/hepdata.12879

None

33 data tables

Table 1

AUTHORS FIT D2(SIG)/D(XL)/D(PT**2) BY (1-XL)**POWER*EXP(-SLOPE*PT**2).

Table 2

AUTHORS FIT D2(SIG)/D(XL)/D(PT**2) BY (1-XL)**POWER*EXP(-SLOPE*PT**2).

Table 3

AUTHORS FIT D2(SIG)/D(XL)/D(PT**2) BY (1-XL)**POWER*EXP(-SLOPE*PT**2).

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A Study of the Reaction $\pi^- p \to \phi \phi n$ at 16-{GeV}/$c$

The Aachen-Bari-Bonn-CERN-Glasgow-Liverpool-Milan collaboration Armstrong, T.A. ; Baccari, B. ; Booth, P.S.L. ; et al.

Nucl.Phys.B 196 (1982) 176-188, 1982.

Inspire Record 165251 DOI 10.17182/hepdata.34217

The reaction π − p → φφ n has been isolated at 16 GeV/ c and its cross section determined to be 40 ± 10 nb. The φφ mass spectrum shows a threshold enhancement between 2.1 and 2.5 GeV. A successful description of the angular content of the φφ system requires two interferingss J P = 2 + states.

2 data tables

Table 1

No description provided.

Table 2

SLOPE OF DIFFERENTIAL TP(P=3,P=2) DISTRIBUTION.

Interference between (p,f0 ...) and (rho0,b0,...) exchanges in pion diffraction dissociation at 16 gev/c

The Aachen-Berlin-Bonn-CERN-Heidelberg collaboration Beaupre, J.V. ; Deutschmann, M. ; Graessler, H. ; et al.

Phys.Lett.B 41 (1972) 393-396, 1972.

Inspire Record 75614 DOI 10.17182/hepdata.28235

It is found in the reactions π ± p →( π ± π + π − )p, believed to be dominated by diffraction dissociation, that the d σ d t′ distributions show a “cross-over” effect at t ′ ≈ 0.15, similar to the effect observed in elastic scattering. This gives evidence for the interference of ( ϱ 0 , B 0 ,…)-exchanges with ( P , f 0 , …) -exchanges in pion diffraction dissociation reactions. No such evidence is found for baryon dissociation, π ± p → π ± (p π + π − ), at the same energy.

8 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Backward Production of a Spin Parity 1+ $K \rho$ Resonance at 1.28-{GeV}

The Amsterdam-CERN-Nijmegen-Oxford collaboration Gavillet, P. ; Diaz, J. ; Dionisi, C. ; et al.

Phys.Lett.B 76 (1978) 517-522, 1978.

Inspire Record 130237 DOI 10.17182/hepdata.27442

A ( K π π ) + mass enhancement is observed in the reactions K − p → Ξ −K o + π + π o − when events with a small (K − → Ξ − ) four momentum transfer squared are selected. The signal is also visible in the reaction K − p → Ξ − π + + neutrals. The enhancement, centered at 1.28 GeV, is seen to decay preferentially into Kϱ with spin-parity J P = 1 + . The cross section for K − p→ Ξ − C + (1.28) with C + → K ϱ at 4.15 GeV/c incident K − momentum is (6.2 ± 0.6) μ b.

1 data table

Table 1

ASSUMING ISOSPIN HALF FOR C(1280)+ AND C(1400)+. FOR C(1280)+, D(SIG)/DU HAS SLOPE OF 1.60 +- 0.30 GEV**-2. THESE AXIAL VECTOR RESONANCES ARE HERE ENCODED AS QLOW(1240)+ AND QHIGH(1340)+.

Backward Production of the $B$ Meson in $K^- p$ Interactions at 4.2-{GeV}/$c$

The Amsterdam-CERN-Nijmegen-Oxford collaboration Gavillet, P. ; Dionisi, C. ; Gurtu, A. ; et al.

Phys.Lett.B 78 (1978) 158-161, 1978.

Inspire Record 131673 DOI 10.17182/hepdata.27430

The backward production of the B(1235) meson is studied in the reaction K − p → Σ − π + ω . This reaction is observed in the final state Σ − π + π + π − π 0 . A π + ω mass enhancement is visible in the region of the B meson for events with small | u |K − → Σ − ) squared four-momentum transfer. The properties of the enhancement agree with those of the B meson. The cross section for K − p → Σ − B + at 4.15 GeV c incident K − momentum is (3.2 ± 0.5) μb . The backward production of the B meson is compared with similar baryon exchange productions of the A 1 and C(Q 1 ) axial vector mesons observed in the same experiment.

2 data tables

Table 1

No description provided.

Table 2

No description provided.