Armstrong, T.
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Production of $\pi^0$ and Eta0 at 11-degrees in $p p$ Collisions at $\sqrt{s}=63$-{GeV}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Z.Phys.C 18 (1983) 5, 1983.
Inspire Record 188928 DOI 10.17182/hepdata.16326

The inclusive π0 production cross-section and the η/π0 ratio have been measured inpp collisions at\(\sqrt s= 63 GeV\) at the CERN Intersecting Storage Rings in the rapidity range 2.00<y<2.75. The π0 cross-section exhibits a strongy-dependence and falls more steeply as a function ofpT, compared with the cross-section measured aty∼0. We find a value of 0.46±0.07 for the η/π0 ratio with no significantpT dependence over the range 2.0<pT<4.0 GeV/c.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Experimental Investigation of the Deuteron Photodisintegration in the $\Delta$ Resonance Region

Arends, J. ; Gassen, H.J. ; Hegerath, A. ; et al.
Nucl.Phys.A 412 (1984) 509-522, 1984.
Inspire Record 190187 DOI 10.17182/hepdata.50236

Differential cross sections for the deuteron photodisintegration process were measured for photon energies between 200 and 440 MeV using the tagged photon beam facility of the Bonn 500 MeV synchrotron. At eight angles between 18° and 145° charged particles were detected simultaneously in time-of-flight spectrometers consisting of scintillation counters. Above the resonance region the measured cross sections agree fairly well with earlier results, whereas there are larger discrepancies at low photon energies.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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INCLUSIVE K0(S) LAMBDA AND anti-LAMBDA PRODUCTION IN anti-p p INTERACTIONS AT 22.4-GeV/c

The Alma Ata-Dubna-Helsinki-Moscow-Prague-Tbilisi collaboration Batyunya, B.V. ; Boguslavsky, I.V. ; Gramenitsky, I.M. ; et al.
Z.Phys.C 25 (1984) 213, 1984.
Inspire Record 194651 DOI 10.17182/hepdata.2004

InclusiveKs0, Λ and\(\bar \Lambda\)-production has been investigated in\(\bar p\)p-interactions at 22.4 GeV/c. Total and topological cross sections and multiplicity characteristics of neutral strange particles have been determined. DifferentialKs0 and Λ-cross sections and also characteristics of annihilation processes with neutral kaon production have been studied. It is shown that the difference of the shapes of the invariantx-distributions forK-mesons in the fragmentation region for annihilation and non-annihilation processes can be described in the framework of the “dual” valon model, but not by considering the current (undressed) quark recombination mechanisms only. The polarization of Λ and\(\bar \Lambda\)-hyperons has been measured.

4 data tables
Table 1

No description provided.

Table 2

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Table 3

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D*+- Production by e+ e- Annihilation Near 34.4-GeV Center-Of-Mass Energy

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 126 (1983) 493-498, 1983.
Inspire Record 196842 DOI 10.17182/hepdata.30721

D ∗± production via e + e − →D ∗± X has been measured at an average CM energy of 34.4 GeV. The D ∗± energy spectrum is hard, with a maximum near χ = 0.6. The size of the D ∗ cross section, R D ∗ = σ( e + e − → D ∗ X ) σ μμ = 2.50 ± 0.64 ± 0.88 (assuming R D ∗0 = R D ∗+ ) indicates that a large fraction of charm quark production yields D ∗ mesons. The D ∗± angular distribution exhibits a forward—backward asymmetry, A = −0.28 ± 0.13. This is consistent with that expected in the standard theory for weak neutral currents and leads to | g A c | = 0.89 ± 0.44 for the axial vector coupling of the charm quark.

3 data tables
Table 1

ASSUMES EQUAL RATES FOR CHARGED AND NEUTRAL D*'S. ONLY CHARGED ARE DETECTED.

Table 2

DATA PEAKS AT X=0.6 TO 0.8.

Table 3

ASYMMETRY MEASUREMENT. THETA IS THE ANGLE BETWEEN THE E- AND THE D*.


The Ratio of the Nucleon Structure Functions f2 (n) for Iron and Deuterium

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 123 (1983) 275-278, 1983.
Inspire Record 188925 DOI 10.17182/hepdata.30745

Using the data on deep inelastic muon scattering on iron and deuterium the ratio of the nucleon structure functions F 2 N ( Fe )/ F 2 N ( D ) is presented. The observed x -dependence of this ratio is in disagreement with existing theoretical predictions.

1 data table
Table 1

RANGE OF Q*2 VARIES WITH X. E.G. AT X=0.05 , 9<Q2<27. AT X=0.65 , 36<Q2<170 GEV**2.


Observation of a Narrow State at 2.46-GeV/c**2: A Candidate for the Charmed Strange Baryon a+

Biagi, S.F. ; Bourquin, M. ; Britten, A.J. ; et al.
Phys.Lett.B 122 (1983) 455, 1983.
Inspire Record 188802 DOI 10.17182/hepdata.30747

A narrow state has been observed in the reaction Σ − + Be → ( Λ K − π + π + ) + X in an experiment at the CERN SPS hyperon beam. At 2.46 GeV/ c 2 the effective ( Λ K − π + π + ) mass distribution shows an excess of 82 events above a background estimated to be 147, corresponding to a statistical significance of more than 6 standard deviations. The positive charge of the observed final state, which has strangeness −2, suggests the interpretation as a Cabibbo favoured decay of the charmed strange baryon, A + [quark content (csu)]. The cross section times branching ratio is measured to be σ · B = (5.3 ± 2.0) μ b/ (Be nucleus) for x > 0.6. The invariant production cross section is described by E d 3 σ /d p 3 ∞ (1 - x ) (1.7±0.7) exp[−(1.1 −0.4 +0.7 ) p T 2 ].

1 data table
Table 1

No description provided.


Observation of Jets in High Transverse Energy Events at the CERN Proton - anti-Proton Collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 123 (1983) 115-122, 1983.
Inspire Record 188735 DOI 10.17182/hepdata.30754

With a segmented total absorption calorimeter of large acceptance, we have measured the total transverse energy spectrum for pp̄ collisions at s 1 2 = 540 GeV up to ΣE T = 130 GeV in the pseudo-rapidity range | η |< 1.5. Using two different algorithms, we have looked for localized depositions of transverse energy (jets). For ΣE T > 40 GeV , the fraction of events with two jets increases with Σ E T ; this event structure is dominant for ΣE T > 100 GeV. We measure the inclusive jet cross section up to E T (jet) = 60 GeV and the two-jets mass distribution to 120 GeV/ c 2 . The measured cross sections are compatible with the predictions of hard scattering models based on QCD.

2 data tables
Table 1

DATA TAKEN IN 1981 WITH GLOBAL TRANSVERSE ENERGY TRIGGER.

Table 2

DATA TAKEN IN 1982 WITH LOCAL TRANSVERSE ENERGY TRIGGER.


Inclusive Charged Particle Production at the CERN anti-p p Collider

The UA2 collaboration Banner, M. ; Bloch, P. ; Bonaudi, F. ; et al.
Phys.Lett.B 122 (1983) 322-328, 1983.
Inspire Record 190969 DOI 10.17182/hepdata.30782

Transverse momentum distributions of pions, kaons and protons have been measured around 90° in the UA2 detector at the SPS p p collider, at a CM energy of 540 GeV. All the cross sections have increased by more than a factor of 2 over those measured at ISR energies and exhibit a flatter behaviour with respect to transverse momentum.

1 data table
Table 1

No description provided.


MEASUREMENT OF THE DEUTERON STRUCTURE FUNCTION F2 AND A COMPARISON OF PROTON AND NEUTRON STRUCTURE

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 123 (1983) 123-126, 1983.
Inspire Record 188737 DOI 10.17182/hepdata.30753

The deuteron structure function F 2 d has been measured in 280 GeV μ + d interactions. Existing measurements of F 2 p , made with the same apparatus, are used to calculate F 2 p − F 2 n and F 2 n F 2 p . The ratio F 2 n F 2 p has a similar x dependence to that of earlier measurements at lower Q 2 .

10 data tables
Table 1

No description provided.

Table 2

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Table 3

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Measurement of differential cross sections for processes $\gamma d\to p n$, $\pi^0 d$, and $p X$ in the energy range of dibaryon resonances

Baba, K. ; Endo, I. ; Fukuma, H. ; et al.
Phys.Rev.C 28 (1983) 286-293, 1983.
Inspire Record 195610 DOI 10.17182/hepdata.26333

The differential cross section for the reactions γd→pn, γd→π0d, and γd→pX has been measured by using a tagged photon beam in the energy range of dibaryon resonances. The most characteristic feature of the data for γd→pn is a forward nonpeaking angular distribution. This behavior is in complete disagreement with the existing predictions which take into account the dibaryon resonances. A phenomenological analysis is made by slightly modifying the model of the Tokyo group, but no satisfactory result is obtained. The data for γd→π0d at large angles show that the differential cross section decreases exponentially as a function of pion angle. A comparison is made with a Glauber model calculation. The result seems to be rather in favor of the existence of dibaryon resonances, but a clear conclusion is not possible because of a lack of more accurate data. In the process γd→pX, a broad peak due to quasifree pion production is observed, but the limitation of experimental sensitivity does not allow us to have a definite conclusion for the dibaryon resonance of mass 2.23 GeV conjectured by the Saclay group.

6 data tables
Table 1

No description provided.

Table 2

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Table 3

FOR ANGLES >16 DEG THE OVERALL UNCERTAINTY IN ABSOLUTE NORMALIZATION IS ABOUT 10%.

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