Chabaud, V.
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Measurement of the Reactions $\bar{P} P \to \bar{\Lambda} \Lambda$, $\bar{p} p \to \bar{\Lambda} \Sigma^0$ and $\bar{P} P \to \bar{\Lambda}$ (Missing Mass) at 6-{GeV}

The CERN-Munich collaboration Becker, H. ; Blanar, G. ; Blum, W. ; et al.
Nucl.Phys.B 141 (1978) 48-64, 1978.
Inspire Record 130450 DOI 10.17182/hepdata.34946

None

2 data tables match query
Table 1

OVERALL NORMALIZATION ERROR NOT INCLUDED. -TMIN IS 0.015 (0.023) GEV**2 FOR THE LAMBDA (SIGMA0) REACTION.

Table 2

INCLUDING NORMALIZATION UNCERTAINTY IN ERRORS. USING EMPIRICAL FITS TO D(SIG)/DT FOR -T > 1.0 GEV**2.


Measurement of the Baryon Exchange Reactions $K^- p \to \Lambda \eta$, $K^- p \to \Lambda \pi^0$ at 6-{GeV}/$c$ and the Value of the $\eta N N$ Coupling Constant

Becker, H. ; Blanar, G. ; Blum, W. ; et al.
Nucl.Phys.B 167 (1980) 292-306, 1980.
Inspire Record 143463 DOI 10.17182/hepdata.43413

In order to determine the ηNN coupling constant we have measured the two reactions K − p→ Λη and K − p→ Λπ 0 with a magnetic wire chamber spectrometer which contained a gamma counter for the γγ decays of π 0 and η. The Λ polarization and the differential cross sections are given. The latter have quite different u dependences. Their ratio is interpreted, in terms of a nucleon-Regge exchange model, as the effect of a small ηNN coupling constant for which we obtain G η NN 2 = G π NN 2 · (0.26 ± 0.10) as allowed by SU(3). The large value given by Heisenberg's non-linear field theory, G η NN 2 = G π NN 2 · 0.9, is excluded by this measurement if the characteristic u dependence of the Λπ 0 channel is attributed to N α Regge exchange.

4 data tables match query
Table 1

Axis error includes +- 10/10 contribution.

Table 2

No description provided.

Table 3

Axis error includes +- 10/10 contribution.

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Measurement and Analysis of the Reaction $\pi^- p \to \rho^0 n$ on a Polarized Target

The CERN-Munich collaboration Becker, H. ; Blanar, G. ; Blum, W. ; et al.
Nucl.Phys.B 150 (1979) 301-325, 1979.
Inspire Record 132603 DOI 10.17182/hepdata.34819

The reaction π − p→ π + π − n has been measured in a high-statistics experiment on a transversely polarized proton target at 17.2 GeV, and unexpectedly large nucleon polarization effects have been observed. Combining the results of this experiment with a measurement on a hydrogen target allows a model-independent partial-wave analysis in terms of the “nucleon transversity” amplitudes. Unique or at most twofold ambiguous solutions are obtained. In particular we find a high lower limit ( ⪆30% ) of the spin non-flip unnatural exchange amplitudes at low | t |. These amplitudes, interpreted as being due to the exchange of an object with the quantum numbers of the A 1 , have been assumed to be absent in previous analyses. In checking the consequences of this finding on the old results, we test the validity of the rank-two assumotions for the density matrix. We find a small but significant deviation, which shows the need for a new phase-shift analysis including the A 1 exchange contribution.

2 data tables match query
Table 1

MASS DEPENDENCE OF NORMALIZED T-CHANNEL MOMENTS SCALED TO 100 PCT POLARIZED PROTONS.

Table 2

T DEPENDENCE OF NORMALIZED T-CHANNEL MOMENTS IN THE RHO REGION SCALED TO 100 PCT POLARIZED PROTONS.


Forward $K^*$+ (892) Production in $K^+ p \to \pi^+ K^0_S p$ at 12.7-{GeV}/$c$

Sacharidis, E.J. ; Blum, W. ; Dietl, H. ; et al.
Nucl.Phys.B 179 (1981) 9-32, 1981.
Inspire Record 154321 DOI 10.17182/hepdata.34347

We have measured 618 K + p → π + K S 0 p events at 12.7 GeV/ c incident lab momentum, mass range 790 ⩽ m π + K s 0 ⩽ 990 MeV and t range 0.01 ⩽ − t ⩽ 0.60 (GeV/ c ) 2 . The π + K S 0 mass spectrum is dominated by the K ∗+ (892) resonance and a Breit-Wigner fit yields a mass m = 893.5 ± 1.1 MeV and a width Γ = 33.2 ± 4.1 MeV which is much narrower than measured hitherto. The t distribution of K ∗+ (892) events shows a dip in the forward direction and an exponential fall off thereafter, consistent with dominance of helicity flip amplitudes. The spin density matrix is almost saturated by ρ 11 and ρ 1−1 which are very close to their maximum allowed value of 1 2 throughout the measured t range except in the very forward direction where ρ 00 and Re ρ 10 deviate from zero. Natural parity exchanges, therefore, dominate with unnatural parity exchanges being restricted to a small region in the forward direction. A Regge pole analysis of the differential cross sections of the present measurement in conjunction with previously measured total cross sections supports the f-coupled-pomeron hypothesis.

3 data tables match query
Table 1

SUBTRACTED BACKGROUND IS PHASE SPACE.

Table 2

SUBTRACTED BACKGROUND IS AN INCOHERENT S-WAVE WITH EXPONENTIAL T-DEPENDENCE WITH SLOPE OF 6 GEV**-2.

Table 3

Axis error includes +- 15/15 contribution.


Anti-proton-proton elastic scattering at 3.55 gev/c

Baker, W.F. ; Carlson, P.J. ; Chabaud, V. ; et al.
Nucl.Phys.B 12 (1969) 5-8, 1969.
Inspire Record 56106 DOI 10.17182/hepdata.35577

Antiproton-proton elastic scattering has been measured at 3.55 GeV/ c in the c.m. angular range from 20° to 77° and from 109° to 160°. Forward elastic scattering shows a structure near t = −0.5 (GeV/ c ) 2 . In the backward region two events are observed.

1 data table match query

Study of the Charge Exchange Reactions $\pi^- p \to (\pi^0$, $\eta$, $\eta^\prime$) $n$ at 63-{GeV}

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Z.Phys.C 8 (1981) 95, 1981.
Inspire Record 156266 DOI 10.17182/hepdata.49658

None

4 data tables match query
Table 1

INCLUDING SYSTEMATIC ERRORS.

Table 2

STATISTICAL ERRORS ONLY.

Table 3

STATISTICAL ERRORS ONLY.

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A2- Production in the Reaction $\pi^- p \to K^- K^0_S p$ at 9.8-{GeV} and 18.8-{GeV}

The CERN-Munich collaboration Chabaud, V. ; Hyams, B. ; Jones, C. ; et al.
Nucl.Phys.B 145 (1978) 349-366, 1978.
Inspire Record 131631 DOI 10.17182/hepdata.34875

Results of two spark chamber experiments on A 2 − production in the reaction π − p → K − K S 0 (→ π + π − )p at 9.8 and 18.8 GeV are presented. Decay angular distributions and differential cross sections are given, and the energy dependence of the cross section σ [ π − p → A 2 − (→ K − K 0 )p] is compared with results from π − p → A 2 − (→ 3 π )p.

4 data tables match query
Table 1

FITS WITH CONSTANT BACKGROUNDS. A TWO-PARAMETER LINEAR BACKGROUND GIVES MUCH LARGER ERRORS.

Table 2

INTEGRATED OVER M(K AK) = 1.20 TO 1.42 GEV.

Table 3

No description provided.

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Elastic and total $\pi^{+}\pi^{-}$ cross-sections from a high statistics measurement of the reaction $\pi^{-}p \to \pi^{+}\pi^{-}n$ at 63 GeV/c

Weilhammer, P. ; Berglund, A. ; Chabaud, V. ; et al.
2 (1979) 628-635, 1979.
Inspire Record 148986 DOI 10.17182/hepdata.75420

A sample of about 230000 events of the reaction pi /sup -/p to pi /sup +/ pi /sup -/n, measured with a magnetic forward spectrometer set up in an unseparated pi /sup -/ beam with a momentum of 63 GeV/c at the SPS has been analysed in terms of one pion exchange. The elastic pi /sup +/ pi /sup -/ cross section has been determined using an extrapolation to the pion pole in the mass range up to m( pi /sup +/ pi /sup -/)=4 GeV. The total pi /sup +/ pi /sup -/ cross section is obtained via the optical theorem. (7 refs).

4 data tables match query
Table 1

INTEGRATED 2- S-WAVE INTENSITY FOR 1500 TO 1800 MEV, INCLUDING SIGNIFICANT BACKGROUND.

Table 3

No description provided.

Table 4

No description provided.

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Diffractive Production of Strange Mesons at 63-{GeV}

The ACCMOR collaboration Daum, C. ; Hertzberger, L. ; Hoogland, W. ; et al.
Nucl.Phys.B 187 (1981) 1-41, 1981.
Inspire Record 164180 DOI 10.17182/hepdata.34277

Nearly 200 000 examples of the diffractive process K − p → K − π − π + p at 63 GeV have been obtained using a two magnet spectrometer equipped with Čerenkov counters for secondary particle identification. In addition some 2000 examples of the process K − p → ω K − p have been obtained. The K ππ data have been subjected to partial-wave analysis. The dominant J P = 1 + system couples to K ∗ π , in both S and D waves, ϱ K, κπ and ε K. The data confirm the existence of two J P = 1 + Q mesons and their masses, widths and branching ratios are given. The ifωK data show that the couplings of the Q mesons to ω K are approximately equal to the couplings to ϱ 0 K. The two 1 + nonets expected in the quark model are discussed in the light of this and other recent experiments. There is strong evidence for a broad J P = 0 − resonance at about 1.46 GeV. At higher masses, structure in the J P = 2 − partial waves establishes the existence of at least one J P = 2 − L meson.

1 data table match query
Table 1

JP=1+ S-WAVE PARTIAL WAVE INTENSITIES AND TOTAL INTENSITY FOR Q-REGION. THE <K* PI> INTENSITY IS DOMINATED BY QHIGH. THE <K RHO> AND <KAPPA PI> INTENSITIES ARE DOMINATED BY QLOW.


Observation of $D^*$+- and ($\bar{D}$)0 / $D^\pm$ Production in High-energy $\pi^-$ Be Interactions at the {SPS}

The ACCMOR & Amsterdam-Bristol-CERN-Cracow-Munich-Rutherford collaborations Bailey, R. ; Bardsley, D.G. ; Becker, H. ; et al.
Phys.Lett.B 132 (1983) 230-236, 1983.
Inspire Record 190658 DOI 10.17182/hepdata.30633

An experiment has been performed to search for associated hadronic production of charmed mesons, using a large-aperture forward magnetic spectrometer setup in a π − beam at the CERN SPS. A prompt electron trigger was used to select events containing a pair by charmed particles. D mesons have been identified by reconstruction of hadronic decay modes such as Kπ, Kππ. Data have been taken at 120, 175, and 200 GeV, The D D cross section measured at 175 200 GeV is σ( D D ) = (48 ± 15) μ b with a systematic uncertainty of ±50%. The energy dependence of the cross section is measured to be σ( D D ) [120 GeV )/σ( D D [175/200 GeV ] = 0.62 ± 0.34 .

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.