共查询到20条相似文献,搜索用时 46 毫秒
1.
S. Lichtman J.M. Bishop N.N. Biswas N.M. Cason E.A. Harrington V.P. Kenney W.D. Shephard P.H. Stuntebeck 《Nuclear Physics B》1976,105(2):229-240
Studies have been made of the rare reactions and , and of and , with cross sections of 18.5 ± 5.5, 10.7 ± 3.0, 12.0 ± 5.0, and 19.7 ± 4.8 μb, respectively. Production characteristics of these reactions are examined and effective-mass spectra are presented. There is no significant evidence in the data for production of Ψ(3095) in the baryon-antibaryon system, or for any other high-mass resonances. 相似文献
2.
M.A. Jabiol D. Denegri C. Louedec F. Grard C. Poiret R. Windmolders M.I. Bogoljubsky A.M. Moiseev E.H. Starchenko E. De Wolf M. Barth M. Van Immerseel K.G. Zaitsev E.S. Lukin A.S. Proskurjakov L.N. Smirnova 《Nuclear Physics B》1981,183(3):330-348
The cross sections of several exclusive reactions in interactions are given. In the channels which dominate the interactions, the single and double diffractive dissociations are analysed and compared to the results obtained with K±p interactions at the same energy, pp and interactions at other energies. The test of factorization at the p → pπ+π? vertex is well verified. The process is studied and the cross sections of production are also given. 相似文献
3.
A.A. Carter M. Coupland E. Eisenhandler C. Franklyn W.R. Gibson C. Hojvat D.R. Jeremiah P.I.P. Kalmus T.W. Pritchard M. Atkinson P.J. Duke D.T. Williams J.N. Woulds G.T.J. Arnison A. Astbury D. Hill D.P. Jones 《Nuclear Physics B》1977,127(2):202-241
The polarization parameter P for the reactions and has been measured over essentially the full angular range at ll laboratory momenta between 1.0 and 2.2. GeV/c, using a proton target polarized perpendicular to the scattering plane. The angles and momenta of both final state particles were determined from wire spark chambers, using the deflection caused by the polarized target magnet. Between 1000 and 5300 π?π+ events, and 140 and 1300 K?K+ events, were measured at each momentum. Differential cross sections for were obtained. These are in excellent agreement with previous results. The polarization parameter for both channels is very close to +1 over much of the angular range. Legendre polynomial fits to the data are presented. 相似文献
4.
C. Bruneton J. Bystricky G. Cozzika J. Deregel A. Derevschikov Y. Ducros A. Gaidot M.Yu. Kazarinov V.P. Kanavets F. Khantine-Langlois B. Khatchaturov F. Lehar A. De Lesquen Yu. Matulenko J.P. Merlo A.P. Meschanin S. Miyashita J. Movchet J. Strachota 《Nuclear Physics B》1977,124(4):391-408
The differential cross sections for elastic scattering at 39 and 44.5 GeV/c, respectively, have been measured in the interval of momentum transfer squared 0.15 ≤ ovbt| ≤ 2 (GeV/c)2. 相似文献
5.
Y. Eisenberg A. Engler B. Haber U. Karshon G. Mikenberg S. Pitluck E.E. Ronat A. Shapira G. Yekutieli 《Physics letters. [Part B]》1974,52(2):239-242
Rare decay modes of the f meson are studied in the final states Δ++π+π?π+π?, Δ++π+π?MM and Δ++π+π?π+π?MM. The ratio is 0.23 ± 0.09 and Γ(f → 4 π) saturates the f inelasticity. A 2 s.d. upper limit of 0.09 is found for the branching ratio . 相似文献
6.
Results are reported on the reaction at six lab momenta spanning the region from 0.686 to 1.098 GeV/c. The cross section for this process drops from 5.2 ± 0.4 mb at 0.686 GeV/c to 2.9 ± 0.2 mb at 1.098 GeV/c. Resonance production is determined by means of a model which includes Bose symmetrization and Breit-Wigner amplitudes. The likelihood fit to the resonance channels yields a few per cent ?ππ, approximately 10% in each of the channels fππ, ??, and A2π, and about 40% ?f production, with errors on the order of 5%. Excellent fits to the mass distributions are obtained. Essentially all production and decay angular distributions are found to be uniform, with only a few small deviations from isotropy reported. The angular correlations between like and unlike charged pion pairs are also found to be fit extremely well by the simple model of resonance production with Bose symmetrization. 相似文献
7.
R. Barloutaud A. Borg F. Brun D. Denegri C. Louedec F. Pierre M. Spiro B. Drevillon B. Chaurand G. Labrosse R. Lestienne D. Linglin R.A. Salmeron T.P. Shah K. Paler R.J. Miller J.J. Phelan 《Nuclear Physics B》1973,59(2):374-411
We have studied the system in the 14.3 GeV/c reactions K?p → K?π+π?p, . The data have been obtained from a 500 000 picture exposure of the CERN 2m HBC. The first two final states are dominated by Q-production in the Kππ system; there is also an L-signal at M (Kππ) ~ 1.75 GeV. The reaction cross sections are compared to K?p data at other energies. We discuss the Kππ mass dependence of the diffractive production slope. Evidence is presented for a Q?p versus Q+p differential cross section cross-over around |t| = 0.17 GeV2. A t-channel isospin analysis for the channels in the Q-region shows that the I = 1 exchange amplitude is of the dominant I = 0 exchange amplitude. The Kππ decay distributions indicate a predominant JP = 1+ state in the Q-region, and an important JP = 2? contribution in the L-region. We find neither s-channel nor t-channel helicity conservation at the meson vertex in the Q- or L-regions. The Kπ angular correlation moments within the Kππ diffractive system are characteristic of Kπ elastic scattering, suggesting a π-exchange Deck-type production mechanism. There is evidence for a Kf0 and κπ contribution (where κ is the JP(Kπ) = 0+ state) to the diffractive Kππ system. A fit to the Dalitz-plot distributions for the Q-re gion indicates that the ratio of decay amplitudes decreases with increasing Kππ mass. 相似文献
8.
An empirical investigation of data provides evidence for a dynamical variable connected with the boundary of the physical region. Absence of a fixed u = ?0.2 dip in recent high-energy data disagrees with nucleon-exchange (N) line-reversal expectations from π+p→pπ+ backward scattering. We notice however that the π+p→pπ+ dip is not located at fixed u but remains with a surprising accuracy at a fixed distance u' = u ? umin from the physical boundary. Conjecturing that dips associated with particle exchanges occur at fixed u', we predict that the N-exchange dip in will be considerably displaced at non-asymptotic energies. Our conjecture places the fixed u' = ?0.2 dip near for momenta around 2 GeV/c. Folded distributions exhibit a dip structure at this location. These observations suggest that the failure of line reversal at low energies is due to direct-channel effects, since fixed u' dips occur naturally in geometrical and direct-channel models. 相似文献
9.
E. Eisenhandler W.R. Gibson C. Hojvat P.I.P. Kalmus L.C.Y. Lee Chi Kwong T.W. Pritchard E.C. Usher D.T. Williams M. Harrison W.H. Range M.A.R. Kemp A.D. Rush J.N. Woulds G.T.J. Arnison A. Astbury D.P. Jones A.S.L. Parsons 《Physics letters. [Part B]》1974,49(2):201-204
We present Legendre coefficients from fits to the differential cross-sections for in the momentum range 0.8 to 2.4 GeV/c. The s-dependence of the cross-sections at small angles is examined for evidence of Reggeized baryon exchange, and a fit made to this channel and backward K+p elastic scattering. Comparisons are made with . 相似文献
10.
Y. Pons D. Denegri J.M. Laffaille M. Spiro B. Chaurand G. Labrosse R. Lestienne K. Paler C. Comber S. Tovey 《Nuclear Physics B》1977,123(3):349-360
We discuss the structure of the momentum transfer distributions for the diffractive dissociation processes p → nπ+, p → Δ++π? and . In the near-threshold mass region a clear break of slope is found around t′KK ~ 0.25 GeV2 for the two baryonic channels, whereas no comparable structure is seen for the mesonic system. The differential cross section exhibits a nearly exponential behaviour up to t′pp ~ 0.6 GeV2, falling over three orders of magnitude. The slope variations and breaks are strongly correlated both to the mass region considered and to the decay angle of the fragmentation system. 相似文献
11.
P. Johnson P. Mason H. Muirhead P. Michaelides Ch. Michaelidou G.D. Patel G.W. van Apeldoorn D. Harting D.J. Holthuizen J.M. de Leeuw B.J. Pijlgroms M.M.H.M. Rijssenbeck V. Karimaki M. Korkea-Aho R. Kinnunen J. Tuominiemi G. Ekspong T. Moa S. Nilsson 《Nuclear Physics B》1980,173(1):77-92
Simple inclusive cross sections for interactions at 12 GeV/c are given. The data cover prong cross sections, V0 production and resonances. Separation has been made into annihilation and non-annihilation modes. Some implications of the data are discussed. It is pointed out that the ratios of cross sections for production are independent of incident antiproton momentum in annihilation processes, and that data at the highest available pp energies (ISR) tend to the same value. 相似文献
12.
A. Berglund T. Buran P.J. Carlson C.J.S. Damerell I. Endo A.R. Gillman V. Gracco R.J. Homer M.J. Hotchkiss A. Lundby M. Macri B.N. Ratcliff A. Santroni T. Tso F. Wickens J.A. Wilson 《Nuclear Physics B》1978,137(3):276-282
The reaction has been studied at 10.1 GeV/c in the ?t interval from 0.15 to 1.5 (GeV/c)2. A line-reversal comparison with backward elastic scattering π+p → pπ+ shows good agreement for ?t > 0.3 (GeV/c)2. 相似文献
13.
14.
D.B. Bastien M.F. Hodous R.I. Hulsizer A. Napier I.A. Pless J.P. Silverman J. Wolfson P.L. Bastien L.D. Kirkpatrick H.J. Lubatti 《Physics letters. [Part B]》1974,50(2):290-294
We have investigated the interaction at 5.1 GeV/c using the prism plot method. In addition to the final state, we isolate the three particle diffractive dissociation of the proton and antiproton into (pπ+π?) and respectively. We estimate this process accounts for 30% of the final state. 相似文献
15.
G. Dehm G. Göbel W. Wittek G. Wolf G. De-Jong S. Tavernier P. Cornet P. Dufour F. Grard V.P. Henri R. Windmolders G. Charrière W. Dunwoodie A. Grant Y. Goldschmidt-Clermont F. Muller J. Quinquard 《Nuclear Physics B》1974,75(1):47-58
The decay branching ratios of K10 (1420) into K+π?, K0π+π? and K1+(892) π? are measured in the charge exchange reaction using data from a K+d bubble chamber experiment at 4.6 GeV/c incident momentum. For the branching ratio is obtained. The results are compared with previous measurements. 相似文献
16.
T. Fujii T. Kondo F. Takasaki S. Yamada S. Homma K. Huke S. Kato H. Okuno I. Endo H. Fujii 《Nuclear Physics B》1977,120(3):395-422
The differential cross sections for γp→π+n from hydrogen and the ratios from deuterium were measured at nine c.m. angles between 30° and 150° for laboratory photon energies between 260 and 800 MeV. A magnetic spectrometer with three layers of scintillation hodoscope was used to detect charged π mesons. The cross section for γn→π?p was obtained as a product of and the ratio. The overall features in the cross sections of the two reactions, γp→π+n and γn→π?p, and in the ratios, , agree with predictions by Moorhouse, Oberlack and Rosenfeld, and Metcalf and Walker. An investigation of the possible existence of an isotensor current was made and a negative result was found. In detailed balance comparison with the new results on the inverse reaction π?p→γn, no apparent violation of time-reversal invariance was observed. 相似文献
17.
R. Davis R. Ammar W. Kropac H. Yarger B. Werner Y. Cho D. Johnson B. Musgrave T. Wangler 《Nuclear Physics B》1975,96(3):426-434
A search has been made for exotic states produced in K?d interactions at 5.5 GeV/c. The reactions investigated were: K?d→X??pp, and K?d→ M??Σ+p. Upper limits are set for the production cross sections. 相似文献
18.
C.P. Bust J.R. Carter W.W. Neale J.G. Rushbrooke D.R. Ward R.E. Ansorge B.Y. Oh M. Pratap G. Sionakides G.A. Smith J. Whitmore R. Raja L. Voyvodic 《Nuclear Physics B》1978,140(3):409-422
We have investigated the reactions . The final state is dominated by diffractive production of a system which shows a strong tendency to form . The process is also observed in this reaction, indicating an energy dependence of s?1.5±0.1. The channel shows less single diffraction, and has a doubly diffractive component consistent with pomeron factorization. Strong Δ++(Δ++) production is agoain seen, but in contrast to the channel we also observe considerable ?0 production. 相似文献
19.
J. Boucrot B. Bouquet B. DAlmage A. Ferrer A. Jacholkowski A. Lahellec P. Petroff P. Roudeau J. Six F. Navach P. Sonderegger D. Treille P. Rivet A. Volte P. Benkheiri G. de Rosny A. Rouge R. Salmeron H. Yoshida 《Nuclear Physics B》1977,121(2):251-269
Negative results on backward production, via baryon exchange, of exotic non-strange mesons are presented. The reactions π?p→pforwardX?and π?n→ pforwardX?? have been studied with a 12 GeV/cπ? beam in the Omega spectrometer at CERN. No resonant peak in has been seen. The upper limits obtained on cross sections for exotic meson production are lower than the ?? backward production cross section in the π?p→p?? reaction; this result seems to contradict the predictions of the two-component duality model. Compared to already published experiments in the search for exotics produced via baryon exchange, the sensitivity of this experiment is increased by an order of magnitude. 相似文献
20.
We perform a simultaneous analysis of data in the 1–2GeV/c laboratory momentum range. We consider all Barrelet-related π?π+ amplitudes and find the π0π0 data provide a severe constraint, essentially determining all the partial wave amplitudes aside from a residual PF wave ambiguity. We study the resonant character of the partial waves and compare these with the result of Carter's simplified analysis of just the π?π+ data. 相似文献