Scheffler, P.E.
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Production of $\Lambda(c$) With Large X(f) at the {ISR}

The R608 collaboration Chauvat, P. ; Cousins, R. ; Hayes, K. ; et al.
Phys.Lett.B 199 (1987) 304, 1987.
Inspire Record 250761 DOI 10.17182/hepdata.30058

We report results of an inclusive measurement of the charmed baryon, Λ c , in the forward direction of proton-proton interactions with s =63 GeV . The signal, seen in the final state Λ s π + π + π − , has 6.0 σ significance with about 620 events on a large background and corresponds to a cross section times branching ratio of 2.84±0.50±0.72 μ b for Feynman- x F > 0.5 in both hemispheres. Asymmetries are observed in the decay angular distributions which are characteristic of weak decays and have a combined 3.0 σ significance.

1 data table
Table 1

BR. RATIO WAS TAKEN TO BE 0.028+-0.007+-0.011.


$\Lambda^0$ Polarization in Proton Proton Interactions From $sqrt{s} = 31$-{GeV} to 62-{GeV}

The R608 collaboration Smith, A.M. ; Bonino, R. ; Castellina, A. ; et al.
Phys.Lett.B 185 (1987) 209, 1987.
Inspire Record 235588 DOI 10.17182/hepdata.30196

We report Λ 0 -hyperon polarization measurements at the CERN intersecting storage rings from √ s of 31 to 62 GeV. P Λ 0 changes insignificantly, +(0.8±1.7)%, over this range of √ s . However, P Λ 0 is observed to grow with Feynman- x F and with transverse momentum. At an average p t of 1.1 GeV/ c , P Λ 0 depends linearly on x F and approaches −40% at x F =0.8.

1 data table
Table 1

No description provided.


Observation of Correlations Between Forward Protons and 90-degree Trigger Protons at S**1/2 = 62-{GeV}

The R608 collaboration Smith, A.M. ; Meritet, L. ; Reyrolle, M. ; et al.
Phys.Lett.B 184 (1987) 293-298, 1987.
Inspire Record 234498 DOI 10.17182/hepdata.30213

We study the production of π + 's and protons at 90° with p t>1.15 GeV and their correlations with forward protons. Fewer forward protons are observed for a 90° proton trigger than for a π + trigger. This is in qualitative agreement with the idea of an effective diquark scattering mechanism. Additionally, we observe that a K + produced at 90° is correlated with an enhanced forward production of λ O .

1 data table
Table 1

No description provided.


An Experimental Study of the a-Dependence of $J/\psi$ Photoproduction

The Fermilab Tagged Photon Spectrometer collaboration Sokoloff, M.D. ; dos Anjos, J.C.C. ; Appel, J.A. ; et al.
Phys.Rev.Lett. 57 (1986) 3003, 1986.
Inspire Record 235061 DOI 10.17182/hepdata.20205

We have studied the photoproduction of Jψ mesons on H, Be, Fe, and Pb targets using real photons at a mean energy of 120 GeV. The pT2 spectra were used to separate the coherent diffractive signals from the incoherent signals. Parametrizing the per-nucleus cross sections in terms of power-law dependences, Aα, we find that αcoh=1.40±0.06±0.04 for the coherent diffractive signals and αincoh=0.94±0.02±0.03 for the incoherent signals.

1 data table
Table 1

CROSS-SECTIONS ARE RELATIVE TO THAT FOR INCOHERENT J/PSI PRODUCTION OFF BERYLLIUM.


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
Table 1

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

Table 2

No description provided.


Evidence for Pomeron Single Quark Interactions in Proton Diffraction at the {ISR}

The R608 collaboration Smith, A.M. ; Meritet, L. ; Reyrolle, M. ; et al.
Phys.Lett.B 163 (1985) 267-272, 1985.
Inspire Record 216801 DOI 10.17182/hepdata.30332

Measurements are presented of two exclusive diffractive reactions, pp → (Λ 0 φ 0 K + ) p and pp → (Λ 0 Λ 0 p)p , at √ s = 63 GeV . Pronounced correlations with the beam direction are observed (in the rest frame of the forward-going bracketed system) for those outgoing particles which contain the beam valence quarks. In each case there is a forward-Λ 0 in correlation with a backward K + or p, respectively. No such behavior is seen for the particles which do not contain beam valence quarks (φ 0 and Λ 0 , respectively) . Interpreted as examples of pomeron-proton scattering, these results constitute evidence that, for these final states, the pomeron interacts with a single valence quark and apparently back-scatters it. The subsequent hadronization leads to a longitudinal event structure.

3 data tables
Table 1

Cross sections for forward LAMBDA signal counting both arms of the p p interaction.

Table 2

Cross sections for forward LAMBDA signal counting both arms of the p p interaction.

Table 3

No description provided.


Test of {CP} Invariance in $\Lambda^0$ Decay

The R608 collaboration Chauvat, P. ; Erhan, S. ; Hayes, K. ; et al.
Phys.Lett.B 163 (1985) 273-276, 1985.
Inspire Record 216802 DOI 10.17182/hepdata.49640

In an experiment at the CERN intersecting storage rings with √ s = 31 GeV, we have measured αP , the product of asymmetry parameter and polarization, for Λ 0 's and Λ 0 's produced in p p and pp interactions, respectively. The ratio, (αP) Λ /(αP Λ = −1.04±0.29 , is consistent with the value −1, and constitutes the first test of CP invariance in Λ decay.

1 data table
Table 1

The ratio CONST/CONST is obtained under assumption of POL(LAMBDA) = POL(LAMBDABAR).


MEASUREMENT OF THE ASYMMETRY OF ELASTIC PION - PROTON SCATTERING AT 1.4-GeV/c TO 2.1-GeV/c MOMENTA

Budkovsky, P.E. ; Dobrov, V.M. ; Zhurkin, V.V. ; et al.
90-97, 1985.
Inspire Record 214097 DOI 10.17182/hepdata.40129

None

1 data table
Table 1

No description provided.


Large Transverse Momentum $\pi^0$ Production in $\alpha \alpha d d$ and $p p$ Collisions at the {CERN} {ISR}

The BCMOR collaboration Angelis, A.L.S. ; Basini, G. ; Besch, H.J. ; et al.
Phys.Lett.B 185 (1987) 213-217, 1987.
Inspire Record 222768 DOI 10.17182/hepdata.30194

None

1 data table
Table 1

No description provided.


Comparison of $\bar{p} p$ and $p p$ Elastic Scattering With $0.6-{\rm GeV}^ < t < 2.1-{\rm GeV}^2$ at the {CERN} {ISR}

Erhan, S. ; Smith, A.M. ; Meritet, L. ; et al.
Phys.Lett.B 152 (1985) 131-134, 1985.
Inspire Record 206289 DOI 10.17182/hepdata.30431

p p and pp elastic scattering differential cross sections are presented for momentum transfer 0.6< t <2.1 GeV 2 and √ s = 53 GeV. Measurements were made in the same apparatus at the CERN Intersecting Storage Rings. The p p and pp results are in statistical agreement with one another over the entire t range, although the point at t =1.32 GeV 2 is 1.5 σ above the pp data. The p p points appear to have the same shape as the predictions of Donnachie and Landshoff but are significantly lower in magnitude for 0.9< t <1.5 GeV 2 .

1 data table
Table 1

No description provided.