Bonesini, M.
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Comparison of the Reactions K+- p ---> q+- p at Incident Momentum 8.25-GeV/c

The Athens-Brussels-CERN-Democritos-Liverpool-Mons-Vienna collaboration Stergiou, A. ; Apostolakis, A. ; Michaelides, P. ; et al.
Nucl.Phys.B 102 (1976) 1-19, 1976.
Inspire Record 91607 DOI 10.17182/hepdata.36021

In this paper a comparison of the general features of the reactions K ± p→Q ± p (1) at incident momentum 8.25 GeV/ c is presented. The relevant data derive from events yielding four-constraint fits to the reactions K ± p→K ± π + π − p in exposures of the CERN 2m HBC to RF-separated K + and K − beams. The (K ππ ) effective mass distributions, production angular distributions in the Q region (1.2⩽ M (K ππ )⩽1.5 GeV) and corresponding decay angular distributions are exhibited, and background effects due to N ∗ and Δ production are systematically studied. In particular, it is found that the distributions d σ /d t ′ and d σ /d t for reactions (1) are adequately described by exponential functions over the interval 0.05–0.35 GeV 2 , and exhibit a cross-over effect for momentum transfer squared −0.1 GeV 2 . For both reactions a flattening of d σ /d t ′ for t ′ < 0.05 GeV 2 is observed. By studying the Chew-Low plots and the effects of the different cuts it was found that this flattening cannot be attributed to amplitudes with net s -channel helicity flip different from zero, at least at these energies.

2 data tables
Table 1

ABOUT 7 PCT RELATIVE NORMALIZATION UNCERTAINTY FOR K+ AND K- SAMPLES.

Table 2

FITS TO D(SIG)/DT AND D(SIG)/DTP FOR Q+ AND Q- PRODUCTION TO DETERMINE CROSS-OVER POSITIONS. DATA HAVE MASS CUTS TO SELECT K*0 AND REMOVE DEL++ AND DEL0. MIN IS THE MINIMUM VALUE OF -T FOR THE RELEVANT (K PI PI) MASS.


An Amplitude Analysis for the Reaction pi+ p ---> pi+ pi- pi0 Delta++ at 7-GeV/c

Wagner, F. ; Tabak, M. ; Chew, D.M. ;
Phys.Lett.B 58 (1975) 201, 1975.
Inspire Record 91398 DOI 10.17182/hepdata.27792

An amplitude analysis for the reaction π + p → π + π − π 0 Δ ++ at 7 GeV/ c has been performed using the isobar model for the 3 π system. The 3 π -mass covers the range from 0.82 to 1.90 GeV. We observe strong A 2 production. The spin parity of the ω ∗ (1700) is determined to be 3 − . No significant A 1 production can be seen.

2 data tables
Table 1

No description provided.

Table 2

FROM INTEGRATING BREIT-WIGNER FITS TO THE JP=3- AMPLITUDE FOR -T < 0.8 GEV**2.


Inclusive rho0 Production in pi- p Interactions at 205-GeV/c

Winkelmann, F.C. ; Bingham, H.H. ; Chew, D.M. ; et al.
Phys.Lett.B 56 (1975) 101-104, 1975.
Inspire Record 91206 DOI 10.17182/hepdata.27880

The inclusive ϱ ° production cross section has been measured in the reaction π − p → π + π − X at 205 GeV/ c . We find σ ( ϱ ° ) = 13.5 ± 3.4 mb, with most of the production occuring in the central region. Assuming σ ( ϱ + ) ≈ σ ( ϱ − ) ≈ σ ( ϱ ° ), it is concluded that approximately one-third of the pions at this energy come from ϱ -decay.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Production of Nucleon Resonances by Single Diffraction Dissociation at the CERN ISR

Webb, R. ; Trilling, G. ; Telegdi, V. ; et al.
Phys.Lett.B 55 (1975) 331-335, 1975.
Inspire Record 91189 DOI 10.17182/hepdata.27915

The single diffraction dissociation process pp → (p π + π − )p has been studied at the CERN ISR at √ s = 45 GeV and 0.1 < − t < 0.6 GeV 2 . The reaction is dominated by nucleon resonance production: pp → pN (1520) and pp → pN(1688) with cross-sections (0.25 ± 0.08) mb and (0.56 ± 0.19) mb respectively.

2 data tables
Table 1

DIFFERENTIAL CROSS SECTIONS FOR THREE RANGES OF <P PI+ PI-> MASS.

Table 2

FROM BREIT-WIGNER PLUS BACKGROUND FITS. CORRECTIONS FOR OTHER DECAY MODES USE THE PDG 1974 TABLES FOR N(1520) AND N(1688).


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.


Preliminary Result of Frascati (ADONE) on the Nature of a New 3.1-GeV Particle Produced in e+ e- Annihilation

Bacci, C. ; Celio, R.Balbini ; Berna-Rodini, M. ; et al.
Phys.Rev.Lett. 33 (1974) 1408, 1974.
Inspire Record 90991 DOI 10.17182/hepdata.21293

We report on the results at ADONE to study the properties of the newly found 3.1-BeV particle.

1 data table
Table 1

No description provided.


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.


Reaction pi- p ---> x0 n, x0 ---> 2 gamma at Momenta 15-GeV/c and 40-GeV/c

The Serpukhov-CERN collaboration Apel, W.D. ; Bertolucci, Ennio ; Donskov, S V ; et al.
Sov.J.Nucl.Phys. 25 (1977) 300, 1977.
Inspire Record 91260 DOI 10.17182/hepdata.19034

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


K- p Charge Exchange and Hyperon Production Cross-Sections from 860-MeV/c to 1000-MeV/c

Jones, M. ; Levi Setti, R. ; Merrill, D. ; et al.
Nucl.Phys.B 90 (1975) 349-383, 1975.
Inspire Record 91346 DOI 10.17182/hepdata.6742

The K − p reactions leading to charge exchange and hyperon final states have been studied at nine momenta between 862 and 1001 MeV/ c using data from a 600 000 picture exposure of the Lawrence Berkeley Laboratory 25″ liquid hydrogen bubble chamber. Partial cross sections are determined for all final states resolved by kinematic fitting. In addition, differential cross sections are presented for the two-body final states K o n , Λπ o and Σ +- π -+ along with hyperon polarization angular distributions for Λπ o and Σ + π − .

61 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Analysis of the Reaction K- p --> K- pi- pi+ p at 40-GeV/c

The CERN-Serpukhov Boson Spectrometer Group collaboration Antipov, Yu.M. ; Ascoli, G. ; Busnello, R. ; et al.
Nucl.Phys.B 86 (1975) 381-402, 1975.
Inspire Record 90643 DOI 10.17182/hepdata.32087

The reaction K − p → K − π − π + p has been measured at 25 and 40 GeV/ c at the Serpukhov Proton Accelerator. The production cross section at 25 and 40 GeV/ c as a function of momentum transfer and K ππ mass is presented, and results of the partial-wave analysis of the K ππ system yielding information about Q(1300), K ∗ (1400) and L(1770) mesons are discussed.

3 data tables
Table 1

No description provided.

Table 2

K** DEFINED BY 1.30 < M(K PI PI) < 1.54 GEV.

Table 3

L IS DEFINED AS THE 2- STATE WITH 1.6 < M(K PI PI) < 1.9 GEV.