Almeida, S.P.
[2.0, 5.0]
Max results
Sort by Reverse order

Showing 9 of 79 results

Electroproduction of Neutral Pions at Energies Above the Resonance Region

Brasse, F.W. ; Fehrenbach, W. ; Flauger, W. ; et al.
Phys.Lett.B 58 (1975) 467, 1975.
Inspire Record 99604 DOI 10.17182/hepdata.27793

The reaction e p→e'p π 0 has been measured at W =2.55 GeV a fixed electron scattering angle of 10.3°. Two magnetic spectrometers and a lead glass hodoscope were used to detect all four final state particles. Electroproduction cross sections in the t range −0.15 to −1.4 (GeV/ c ) 2 at q 2 = −0.22, −0.55 and −0.85 (GeV/ c ) 2 are presented. Above | t |=0.6 (GeV/ c ) 2 the cross sections are considerably smaller than those for photoproduction.

1 data table
Table 1

NUMERICAL VALUES MEASURED FROM GRAPH IN PREPRINT BY TDBW.


Production and decay of sigma(1660)

Apsell, S.P. ; Ford, P. ; Gourevitch, S. ; et al.
Phys.Rev.D 10 (1974) 1419-1429, 1974.
Inspire Record 95499 DOI 10.17182/hepdata.25064

An investigation has been performed of some properties of Σ(1660) produced in the reaction K−p→Σ+(1660)π− at 2.87 GeV/c incident K− momentum. The decay modes observed for this state include Λ(1405)π and Σπ. The spin and parity are measured to be JP=32−. The differential cross section of the Λ(1405)π decay mode is sharply peaked in the forward direction, falling exponentially with a slope of 5.6 ± 0.7 (GeV/c)−2, while the slope for the Σ0π+ decay mode is 2.1 ± 0.4 (GeV/c)−2. The difference in the ratio of backward to total events for the two decay modes also suggests that two Σ(1660)'s exist.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Study of 4pi system in the rho-prime(1710) meson mass region in the reaction pi- p ---> p pi+ pi- pi- pi0 at 4.5 gev/c momentum.

Kliger, G.K. ; Beketov, G.V. ; Grechko, V.E. ; et al.
Yad.Fiz. 19 (1974) 839-848, 1974.
Inspire Record 95146 DOI 10.17182/hepdata.19145

None

2 data tables
Table 1

No description provided.

Table 2

ALLOWING FOR 65 PCT BACKGROUND.


On helicity conservation in the reaction pi- p ---> a1 p at 4.45 gev/c

Beketov, G.V. ; Zombkovsky, S.M. ; Kaidalov, A.B. ; et al.
Nucl.Phys.B 59 (1973) 265-272, 1973.
Inspire Record 83967 DOI 10.17182/hepdata.32538

Helicity conservation in the reaction π − p → pA 1 at 4.45 GeV/ c has been studied using 50 cm and 55 cm liquid hydrogen bubble chambers. In the Jackson and the helicity frames the dependence of the ϱ matrix elements on the four-momentum transfer squared to the proton ( t ) for A 1 maximum decay has been calculated. The obtained data are in a good agreement with t -channel helicity conservation. The t -channel dependence of the ϱ matrix elements in the mentioned frames is in good agreement with that calculated using the Regge π-pole exchange model (it is suggested that the A 1 maximum nature is explained by a kinematical effect of the Deck type).

1 data table
Table 1

No description provided.


Differences in Total Cross-Section for Momenta Up to 65-GeV/c

Denisov, S.P. ; Donskov, S.V. ; Gorin, Yu.P. ; et al.
Nucl.Phys.B 65 (1973) 1-28, 1973.
Inspire Record 73611 DOI 10.17182/hepdata.32391

Total cross sections for π − , K − and p on protons and deutrons have been measured in the momentum range 15 to 60 GeV/ c . Total cross sections for particle interactions with neutrons have been determined with an energy dependent Glauber correction. Using the positive particle data obtained earlier with the same experimental apparatus, the differences of total cross sections for particles and antiparticles as well as for particles belonging to the same isospin multiplet have been calculated.

16 data tables
Table 1

THESE DATA WERE PREVIOUSLY PUBLISHED IN YU. P. GORIN ET AL., SJNP 15, 530 (1972) OR YF 15, 953 (1972).

Table 2

No description provided.

Table 3

No description provided.

More…

Experimental comparison of anti-d p and anti-p d total cross-sections

Denisov, S.P. ; Donskov, S.V. ; Gorin, Yu.P. ; et al.
Phys.Lett.B 34 (1971) 167-169, 1971.
Inspire Record 69336 DOI 10.17182/hepdata.5847

d ̄ p and p ̄ d total cross-sections have been measured at 13.3 and 6.65 GeV/ c respectively to check CPT-invariance. The standard transmission technique was used. The difference of d ̄ p and p ̄ d total cross-sections appeared to be equal 0.2 ± 2.6 mb. In addition d ̄ d and p ̄ p total cross-sections have been obtained. The experimental data allowed us to derive the total cross-section of antineutrons on protons, neutrons and deutrons.

7 data tables
Table 1

'1'. '2'. '3'. 'GLAUB'.

Table 2

No description provided.

Table 3

No description provided.

More…

Experimental comparison of anti-d p and anti-p d total cross sections

Gorin, Yu.P. ; Denisov, S.P. ; Donskov, S.V. ; et al.
Yad.Fiz. 14 (1971) 134-136, 1971.
Inspire Record 69450 DOI 10.17182/hepdata.19261

None

2 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (GLAUBER).

Table 2

Axis error includes +- 0.0/0.0 contribution (GLAUBER).


Study of a2 and a3 meson production in pi p collisions at 4.45 gev/c

Beketov, G.V. ; Zombkovskii, S.M. ; Konovalov, B.S. ; et al.
Yad.Fiz. 13 (1971) 765-771, 1971.
Inspire Record 69508 DOI 10.17182/hepdata.19293

None

1 data table
Table 1

CROSS SECTIONS VERY SENSITIVE TO BACKGROUND SUBTRACTION.


P-P Interactions at 10 GEV/C

Almeida, S.P. ; Rushbrooke, John G. ; Scharenguivel, J.H. ; et al.
Phys.Rev. 174 (1968) 1638-1661, 1968.
Inspire Record 55886 DOI 10.17182/hepdata.5529

About 3700 two-prong and 5600 four-prong events of 10-GeV/c pp interactions in the Saclay 81-cm hydrogen bubble chamber have been measured and analyzed. The reliability of the identification of the different final states has been checked using Monte Carlo-generated events. For the channels accessible to analysis, cross sections and invariant-mass distributions are given. The c.m. angular distributions and the mean values of the transverse momentum for all final-state particles are shown and discussed. Production of Δ++(1236) accounts for about 30% of the cross section σ(pp→pnπ+)=4.1±0.4 mb. About 50% of the cross section σ(pp→ppπ+π−)=2.4±0.2 mb can be accounted for by Δ++ production. Production of nucleon isobars at 1450, 1520, and 1730 MeV and their subsequent decay into pπ+π− are investigated. Their cross sections, t dependences, and branching ratios are determined, using a one-pion-exchange model (OPEM) for calculating the background distributions. The production of resonances decaying into pπ− at 1236, 1500, and 1690 MeV is seen, and cross sections are given. Resonance production in the ppπ+π−π0 and pnπ+π+π− reactions is studied using background curves calculated with a model based on simple parametrizations of the c.m. momentum distributions. The production of nucleon isobars accounts for nearly 100% of these reactions. For the reactions pp→ppω, ppη, and ppf0, the cross sections found are 0.16±0.03, 0.16±0.07, and 0.10±0.04 mb, respectively, corrected for unobserved decay modes. It is shown that most of the gross features of the pion-production reactions can be explained by the OPEM with the form factors of Ferrari and Selleri.

2 data tables
Table 1

No description provided.

Table 2

No description provided.