Armstrong, T.A.
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Study of the A-dependence of Inclusive $p$, $\bar{p}$, $\Lambda$ and $\bar{\Lambda}$ Production in $\pi^\pm$ Nucleus Interactions at 30-{GeV}/$c$

The CERN-Lisbon-Neuchatel-Paris-Warsaw collaboration Abreu, M.G. ; Armstrong, T. ; Baubillier, M. ; et al.
Z.Phys.C 25 (1984) 115, 1984.
Inspire Record 200776 DOI 10.17182/hepdata.16301

We present the first results on the production of fast (p>10 GeV/c)p,\(\bar p\), Λ and\(\bar \Lambda \) from π± hydrogen and nucleus interactions at 30 GeV/c using the CERN Ω′ spectrometer. We have used five nuclear targets (C, Al, Cu, Sn, Pb) to study theA-dependence of the inclusive particle distributions in the region 0.3<xF<0.6. The high statistical level of our experiment allows us to demonstrate the differentA-behaviour of baryon and antibaryon inclusive reactions. We relate this difference to the final state interaction inside a nucleus using the formation-zone model.

1 data table
Table 1

No description provided.


Observation of Two Nonleading Strangeness 1 Vector Mesons

Aston, D. ; Carnegie, R.K. ; Dunwoodie, W.M. ; et al.
Phys.Lett.B 149 (1984) 258-262, 1984.
Inspire Record 201412 DOI 10.17182/hepdata.33871

We present evidence for the existence of two strange J P = 1 − mesons; one at 1410 MeV/c 2 coupling principally to K ∗ (892)π , and the other at 1790 MeV/c 2 couplingto K π , K ∗ π and ϱ K. The data derive from a partial wave analysis of the K 0 π + π − system produced in the reaction K − p → K 0 π + π − n at 11 GeV /c . The production mechanism and quark model assignment of each state are discussed. The state at 1410 MeV/c 2 most naturally understood as the first radial excitation of the K ∗ (892), and the 1790 MeV/c 2 object can be interpreted as the triplet D wave partner to the 3 − K ∗ (1780).

1 data table
Table 1

No description provided.


MOMENTUM AND ANGULAR DISTRIBUTIONS OF CHARGED SECONDARIES IN 40-GeV/c pi- A INTERACTIONS WITH SINGLE PARTICLE HIGH P(T) TRIGGER

The Berlin-Budapest-Dubna-Prague-Sofiya-Tbilisi-Warsaw collaboration Adam, G. ; Bannikov, A.V. ; Bohm, J. ; et al.
JINR-E1-84-442, 1984.
Inspire Record 203314 DOI 10.17182/hepdata.9861

None

6 data tables
Table 1

No description provided.

Table 2

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Table 3

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CHARGED PARTICLE MULTIPLICITIES IN PI-, K- AND ANTI-P INTERACTIONS WITH NUCLEI AT 40-GEV/C

The RISK collaboration Boos, E.G. ; Mosienko, A.M. ; Pokrovsky, N.A. ; et al.
Z.Phys.C 26 (1984) 43-52, 1984.
Inspire Record 214970 DOI 10.17182/hepdata.22350

Interactions of 40 GeV/c πp-,K− and\(\bar p\) on Li, C, S, Cu, CsI and Pb were studied with the RISK-streamer chamber spectrometer. We present multiplicities of negatively charged particles, as well as of protons, and the correlations between them. The normalized mean multiplicity of negative particles,R−, depends on\(\bar v\), the average number of inelastic collisions as\(R^ -= (0.73 \pm 0.04) + (0.34 \pm 0.02)\bar v\). The dependence of the normalized dispersion of negative particles,D−/<N−>, on the number of protons favours independent collision models and contradicts the coherent tube picture. The excess of fast positive particles behaves asA0.4 and shows, for the heavier nuclei, a clear correlation with identified protons.

2 data tables
Table 1

AVERAGE MULTIPLICITIES OF ALL CHARGED PARTICLES.

Table 2

AVERAGE MULTIPLICITIES OF ALL NEGATIVELY CHARGED PARTICLES.


Real to Imaginary Ratio of the $\bar{p} p$ Forward Elastic Scattering Amplitude in the Momentum Range Between 180-{MeV}/$c$ and 590-{MeV}/$c$

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.
Phys.Lett.B 158 (1985) 180-185, 1985.
Inspire Record 213992 DOI 10.17182/hepdata.30392

The real-to-imaginary ratio of the p p forward elastic scattering amplitude has been measured at the LEAR facility of CERN by the Coulomb-nuclear interference method at seven beam momenta between 181 and 590 MeV/ c . The ratio is positive at 590 MeV/ c , becomes negative below 500 MeV/ c , reaches a minimum at 260 MeV/ c and then crosses zero again at about 230 MeV/ c .

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Inclusive Production of Multistrange Hyperons From 11-{GeV}/$c K^- p$ Interactions

Aston, D. ; Carnegie, R.K. ; Dunwoodie, W.M. ; et al.
Phys.Rev.D 32 (1985) 2270, 1985.
Inspire Record 214256 DOI 10.17182/hepdata.70875

Large samples of inclusively produced Ξ−, Ω−, and Ξ0(1530) events are presented from a 1427 events/μb exposure of the large-aperture superconducting-solenoid spectrometer to an 11-GeV/c K− beam. Production characteristics of these states are compared with other data and shown to be consistent with hyperon exchange. Polarization of Ξ− shows an increase in magnitude with both Feynman x and transverse momentum. The Ξ− decay parameters are measured to be αΞ=-0.40±0.03 and ΦΞ=(5±10)° . Results of searches for higher-mass hyperons are presented. The Ξ−(1820)→Ξ0(1530)π− decay is observed, while we fail to confirm the existence of the Σ+(3170).

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Anti-proton - Proton Elastic Cross-sections in the Momentum Range Between 180-{MeV}/$c$ and 600-{MeV}/$c$

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.
Phys.Lett.B 166 (1986) 113-118, 1986.
Inspire Record 217928 DOI 10.17182/hepdata.30308

Differential cross sections for p̄p elastic scattering have been measured in the full angular range for the p̄ momenta between 180 and 600 MeV/ c . It is found that s- and p-wave scattering is dominant below 300 MeV/ c . The s-wave component in the total cross section is 40–60% below 300 MeV/ c , in contrast to the NN scattering where it is about 90%. The s-, p- and d-wave scattering amplitudes are derived.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Evidence for Structure in the 1.7-{GeV} Mass Region of the $K^+ K^-$ Final State Centrally Produced in the Reactions $\pi^+ p \to \pi^+ (K^+ K^-$) $p$ and $p p \to p (K^+ K^-$) $p$ at 85-{GeV}/$c$

The Athens-Bari-Birmingham-CERN collaboration Armstrong, T.A. ; Bloodworth, I.J. ; Carney, J.N. ; et al.
Phys.Lett.B 167 (1986) 133-137, 1986.
Inspire Record 219229 DOI 10.17182/hepdata.30285

The reactions π + p → π + (K + K − )p and pp → p(K + K − )p where the K + K − system is centrally produced have been studied at 85 GeV/ c . The K + K − spectrum contains several structures in the regions of S ∗ ø , f A 2 and f′. Structure is observed in the 1.7 GeV mass region which cannot be attributed to the g meson. The most likely interpretation of the data is that we observe the θ with a mass of 1.742 GeV and a new resonance at a mass of 1.629±0.010 GeV with a width of 0.082±0.030 GeV.

1 data table
Table 1

No description provided.


Measurement of the $\bar{p} p \to \bar{n} n$ Cross-section at Low $\bar{p}$ Momenta

Bruckner, W. ; Dobbeling, H. ; Guttner, F. ; et al.
Phys.Lett.B 169 (1986) 302-308, 1986.
Inspire Record 219986 DOI 10.17182/hepdata.30264

First measurements of the differential cross section are presented for p ̄ p → n ̄ n at LEAR in the momentum range between 180 and 600 MeV/ c . The differential cross sections show a forward peaking followed by a smooth drop-off. No indication of the “bump-dip” structure reported at higher momenta has been observed. The angle-integrated charge-exchange cross sections are determined down to E n ̄ n cm = 6.6 MeV .

2 data tables
Table 1

No description provided.

Table 2

No description provided.


INCLUSIVE SPECTRA OF He, Li, Be, B FRAGMENTS PRODUCED ON NUCLEI BY ELECTRONS WITH ENERGIES OF 2-GeV AND 4.5-GeV AT ANGLE 0

Aivazian, G.M. ; Arutunian, V.N. ; Akhverdian, E.A. ; et al.
EFI-859-10-86-YEREVAN, 1985.
Inspire Record 223426 DOI 10.17182/hepdata.18428

None

2 data tables
Table 1

FIT IN THE RANGE OF KINETIC ENERGY OF FRAGMENTS FROM 4 TO 8 MEV/NUCLEON.

Table 2

FIT IN THE RANGE OF KINETIC ENERGY OF FRAGMENTS FROM 4 TO 8 MEV/NUCLEON.