Date

$D$ Meson Production From 400 GeV/$c p p$ Interactions

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Allison, W.W.M. ; Bailly, J.L. ; et al.
Phys.Lett.B 189 (1987) 476, 1987.
Inspire Record 245101 DOI 10.17182/hepdata.12913

We have measured the inclusive production properties of D and D messons produced from pp interactions at s =27.4 GeV . The differential production cross section is well represented by the empirical form d 2 σ d x F d P 2 T = 1 2 [σ ( D / D )(n+1)b](1−|x F |) n exp (−bp 2 T ) with n=4.9 ± 0.5, b=(1.0±0.1)( GeV /c) −2 , and the inclusive D / D cross section σ ( D / D ) is (30.2±3.3) ωb. The QCD fusion model predicts D / D production which is in good agreement with our data except for the magnitude of the cross section which depends sensitively on the assumed mass of the charm quark.

11 data tables

No description provided.

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BACKWARD SCATTERING IN pi- p ---> p pi-, anti-p p ---> pi+ pi-, K- p ---> p K- AND anti-p p ---> p anti-p AT 8-GeV/c AND 12-GeV/c

The CERN-Lisbon-Moscow-Neuchatel-College de France-Paris collaboration Armstrong, T.A. ; Baubillier, M. ; Brient, J.C. ; et al.
Nucl.Phys.B 284 (1987) 643, 1987.
Inspire Record 230626 DOI 10.17182/hepdata.33525

Data on the reactions π − p → p π − , p p → π + π − , K − p → pK and p p → p p at 8 and 12 GeV/ c are presented. Our results agree with line reversal symmetry (between π − p → p π − and p p → π + π − ), Regge pole behaviour for non-exotic reactions ( π − p → p π − , p p → π + π − ), and universal behaviour for exotic reactions ( p p → p p , K − p → pK − ) with d σ /d u | u =0 ∼ s −10 excluding the existence of a “glory” mechanism in p p elastic backward scattering in our energy range.

4 data tables

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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

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

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

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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Evidence for Narrow States Decaying Into ($\Lambda \bar{p}$ Pions) at 3.1-{GeV}/$c^2$ With Charges +1, 0 and -1

The Bristol-Geneva-Heidelberg-Lausanne-Rutherford collaboration Bourquin, M. ; Brown, Robert M. ; Burckhart, H.J. ; et al.
Phys.Lett.B 172 (1986) 113, 1986.
Inspire Record 228256 DOI 10.17182/hepdata.47311

Evidence for narrow states produced by Σ − interactions in beryllium, and decaying into ( Λ p + pions ), has been obtained in an experiment at the CERN SPS hyperon beam. At 3.1 GeV/ c 2 , the ( Λ p π + π + ), ( Λ p π + π + π − ) and ( Λ p π + π − ) effective mass distributions show an excess of 45, 19 and 62 events above a background of 50, 28 and 187, respectively. The possibility that these three signals are statistical fluctuations is remote. The observed widths of the signals are compatible with the mass resolution of the apparatus, 24 MeV/ c 2 FWHM. We have not been able to find an interpretation of the quantum numbers of the final states, which are baryon number 0, strangeness −1 and charge +1, 0 and −1.

1 data table

The cross section times branching fraction. The differential cross section is fitted by the equation : D3(SIG)/D3(P) = (1-XL)**POWER*EXP(-SLOPE*PT**2).


STUDY OF anti-p p ELASTIC SCATTERING AT 22.4-GeV/c

The Dubna-Alma Ata-Kosice-Moscow-Prague-Sofiya-Helsinki collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Bruncko, D. ; et al.
Sov.J.Nucl.Phys. 44 (1986) 969, 1986.
Inspire Record 222984 DOI 10.17182/hepdata.39005

None

3 data tables

INTEGRATED D(SIG)/D(T).

OBTAINED FROM FIT D(SIG)/D(T)=A*EXP(B*T+C*T**2) IN 0.05 < -T < 0.3.


Study of $\eta \pi^+ \pi^-$ States in the $\rho^\prime$ (1600) Mass Region Photoproduced in the Reaction $\gamma p \to \eta \pi^+ \pi^- p$ at Photon Energies of 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 30 (1986) 531, 1986.
Inspire Record 218611 DOI 10.17182/hepdata.15991

In diffractive photoproduction ofηπ+π−, the two-body substatesηρ0 andA2π are found to contribute significantly to the cross-section forηπ+π− masses below 2.4 GeV. From a spin-parity analysis the branching ratio, ρ′(1600)→ηρ/ρ′(1600)→, is determined to be <0.02 at the 68.3% confidence level. TheA2π component shows an enhancement around 1.7 GeV. The spin-parity analysis indicates a probable contribution to this signal from exclusive photoproduction of theg(1690).

6 data tables

No description provided.

Not corrected for 35% background under the eta --> gamma gamma peak.

Not corrected for 35% background under the ETA --> GAMMA GAMMA peak.

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Observation of Longitudinal Event Structure in Proton Diffractive Dissociation at the {ISR}

The R608 collaboration Smith, A.M. ; Meritet, L. ; Reyrolle, M. ; et al.
Phys.Lett.B 167 (1986) 248-254, 1986.
Inspire Record 219984 DOI 10.17182/hepdata.30272

We study the internal structure of a forward-going pπ + π − π + π − system, with invariant mass in the range 2.5-4 GeV, produced through diffractive dissociation of a beam proton at the ISR. The shape of the system, as seen in its center-of-mass, deviates strongly from isotropic phase space and possesses, rather, a longitudinal structure with a major axis along the incoming proton direction. The final state proton momentum is aligned in the direction of the incoming proton, an effect which becomes more pronounced with increasing diffractive mass.

2 data tables

Acceptance corrected distribution of momentum transfer to the diffractive (p-4pi) system. Data requested from authors.

No description provided.


EXCLUSIVE rho0 PRODUCTION IN DEEP INELASTIC MUON PROTON SCATTERING

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 161 (1985) 203, 1985.
Inspire Record 214930 DOI 10.17182/hepdata.30353

Exclusive ϱ 0 production has been measured in 120, 200 and 280 GeV muon-proton interactions at high Q 2 (1 GeV 2 < Q 2 < 25 GeV 2 ) and W (6 GeV < W < 19 GeV). The photoproduction cross section decreases as 1/ Q 4 . A shallow t distribution, typical of a hard scattering process is observed and the ϱ 0 is found to be dominantly in the helicity zero spin state. The ϱ 0 s are mainly produced by transverse photons and s -channel helicity conservation seems to be invalid. The data cannot be described by the vector meson dominance model. These data show that at high Q 2 even exclusive ϱ 0 muoproduction is a hard scattering process and that the soft hadron-like properties of the photon have disappeared.

8 data tables

No description provided.

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SYSTEMATIC ERROR ON SLOPE IN 0.8.

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Measurement of Small Angle anti-Proton - Proton and Proton Proton Elastic Scattering at the CERN Intersecting Storage Rings

Amos, Norman A. ; Block, M.M. ; Bobbink, G.J. ; et al.
Nucl.Phys.B 262 (1985) 689-714, 1985.
Inspire Record 214689 DOI 10.17182/hepdata.33711

Antiproton-proton and proton-proton small-angle elastic scattering was measured for centre-of-mass energies s =30.6, 52.8 and 62.3 GeV at the CERN Intersectung Storage Rings. In addition, proton-proton elastic scattering was measured at s =23.5 GeV . Using the optical theorem, total cross sections are obtained with an accuracy of about 0.5% for proton-proton scattering and about 1% for antiproton-proton scattering. The measurement of the interference of the Coulomb scattering and the hadronic scattering permits a determination of the ratio of the real-to-imaginary part of the forward hadronic scattering amplitude. Also presented are measurements of the hadronic slope parameter.

13 data tables

No description provided.

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STUDY OF THE REACTION anti-D P ---> anti-P P anti-N AT 12-GeV/c AND anti-N P ELASTIC SCATTERING AT 6-GeV/c

The Dubna-Bucharest-Helsinki-Kosice-Moscow-Prague-Sofiya-Tbilisi-Yerevan collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Bruncko, D. ; et al.
Yad.Fiz. 42 (1985) 903-912, 1985.
Inspire Record 209931 DOI 10.17182/hepdata.39518

None

2 data tables

No description provided.

DATA WERE EXTRACTED FROM ADEUT-BREAKUP EVENTS,SEE R=PR D10, 3573 FOR EXAMPLE.