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$\bar{p} p$ Annihilation Into $\pi^+ \pi^-$ and $K^+ K^-$ From Atomic $p$ States

The ASTERIX collaboration Doser, M. ; Botlo, M. ; Ahmad, S. ; et al.
Nucl.Phys.A 486 (1988) 493-511, 1988.
Inspire Record 261310 DOI 10.17182/hepdata.37012

We have obtained the branching ratios for p p annihilation at rest into π + π − and K + K − in a pure p p initial angular momentum state L = 1. A gaseous hydrogen target at normal pressure and temperature was used and events associated with transitions of the antiprotonic atom to the 2p level were selected by detecting the Balmer X-ray series. The branching ratios for p p annihilation into π + π − and K + K − from the 2p state are (4.81 ± 0.49) × 10 −3 and (2.87 ± 0.51) × 10 −4 , respect The pion yield is slightly larger than in liquid hydrogen, where L = 0 annihilation dominates, while the kaon yield is suppressed by a factor of four. Using these and previous data, we derive the branching ratios for pp annihilation into all ππ and K K modes from S and P states. A measurement in gaseous hydrogen, without X-ray requirement, yields the branching ratios (4.30 ± 0.14) × 10 −3 and (6.92 ± 0.41) × 10 −4 . With the known branching ratios of (3.33 ± 0.17) × 10 −3 and (1.01 ± 0.05) × 10 −3 in liquid hydrogen, we find that (50.3 ± 6.4)% of all annihilations in gas at NTP occur in the initial angular momentum state L = 1.

2 data tables
Table 1

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

Table 2

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


A Luminosity Independent Measurement of the $\bar{p} p$ Total Cross-section at $\sqrt{s}=1$.8-tev

The E-710 collaboration Amos, Norman A. ; Avila, C. ; Baker, W.F. ; et al.
Phys.Lett.B 243 (1990) 158-164, 1990.
Inspire Record 27474 DOI 10.17182/hepdata.29696

We report a measurement of the p p total cross section at √ s =1.8 TeV using a luminosity-independent method. Our result is σ T =72.1±3.3 mb ; we also derive the total elastic cross section σ el =16.6±1.6 mb. A value is obtained for the total single diffraction cross section of 11.7±2.3 mb.

4 data tables
Table 1

No description provided.

Table 2

Assuming RHO = 0.145.

Table 3

No description provided.

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A Measurement of the proton-antiproton total cross-section at s**(1/2) = 1.8-TeV

The E811 collaboration Avila, C. ; Baker, W.F. ; DeSalvo, R. ; et al.
Phys.Lett.B 445 (1999) 419-422, 1999.
Inspire Record 478392 DOI 10.17182/hepdata.28126

We report a measurement of the p p ̄ total cross section at s =1.8 TeV at the Fermilab Tevatron Collider, using the luminosity independent method. Our result is σ T =71.71±2.02 mb. We also obtained values of the total elastic and total inelastic cross sections.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


ANTI-P P TOTAL CROSS-SECTIONS BELOW 420-MEV/C

Bugg, D.V. ; Hall, J. ; Clough, A.S. ; et al.
Phys.Lett.B 194 (1987) 563-567, 1987.
Inspire Record 253124 DOI 10.17182/hepdata.30120

p̄p total cross sections have been measured from 220 to 413 MeV/ c in small (⩽ 10 MeV/ c ) steps of momentum with statistics of ± 0.5 %. There is no evidence for structure in the cross section, and a limit of 8 mb MeV/ c 2 is set with 90% confidence on the strength of any narrow resonance down to 250 MeV/ c .

2 data tables
Table 1

Data taken with long target.

Table 2

Data taken with short target.


Analysis of the Highest Transverse Energy Events Seen in the UA1 Detector at the S $p \bar{p}$ S Collider

The UA1 collaboration Albajar, C. ; Albrow, M.G. ; Allkofer, O.C. ; et al.
Z.Phys.C 36 (1987) 33, 1987.
Inspire Record 248074 DOI 10.17182/hepdata.15751

This is the first full solid angle analysis of large transverse energy events in\(p\bar p\) collisions at the CERN collider. Events with transverse energies in excess of 200 GeV at\(\sqrt s= 630 GeV\) are studied for any non-standard physics and quantitatively compared with expectations from perturbative QCD Monte Carlo models. A corrected differential cross section is presented. A detailed examination is made of jet profiles, event jet multiplicities and the fraction of the transverse energy carried by the two jets with the highest transverse jet energies. There is good agreement with standard theory for events with transverse energies up to the largest observed values\(( \approx \sqrt {s/2} )\) and the analysis shows no evidence for any non-QCD mechanism to account for the event characteristics.

1 data table
Table 1

No description provided.


Anti-p p elastic and charge exchange scattering at 230 mev

Kohno, H. ; Kaneko, S. ; Murata, Y. ; et al.
Nucl.Phys.B 41 (1972) 485-492, 1972.
Inspire Record 75157 DOI 10.17182/hepdata.6879

Reactions p p → p p and p p → n n were studied at the kinetic energy 230 MeV of incident p by using bubble chamber films. Total cross sections for both of the reactions were found to be 51.2 ± 1.6 mb and 9.1 ± 0.6 mb, respectively. Differential cross sections are well explained by the phenomenological theory given by Bryan and Phillips.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Anti-proton - proton elastic scattering at s**(1/2) = 1020-GeV

The E710 collaboration Amos, Norman A. ; Avila, C. ; Baker, W.F. ; et al.
Nuovo Cim.A 106 (1993) 123-132, 1993.
Inspire Record 338043 DOI 10.17182/hepdata.42674

The antiproton-proton small-angle elastic-scattering distribution was measured at\(\sqrt s \) GeV at the Fermilab Tevatron Collider. A fit to the nuclear-scattering distribution in the range 0.065≤|t|≤0.21 (GeV/c)2 givesb=(16.2±0.5±0.5) (GeV/c)−2 for the logarithmic slope parameter. Using the optical theorem and the luminosity from Collider parameters, we obtain σtoto(1+ρ2)1/2 =(61.7±3.7±4.4)mb.

3 data tables
Table 1

No description provided.

Table 2

Cross sections derived assuming RE(AMP)/IM(AMP) = 0.140, see Phys. Lett. B188, 143 (1987).

Table 3

Slope was derived in the t range -0.065 < t < -0.21 (GeV/c)**2.


Antiproton-Proton and Proton-Proton Total Cross Sections from 4 to 20 Bev/c

Lindenbaum, S.J. ; Love, W.A. ; Niederer, J.A. ; et al.
Phys.Rev.Lett. 7 (1961) 185-188, 1961.
Inspire Record 944907 DOI 10.17182/hepdata.191

None

2 data tables
Table 1

'1'. '2'. '3'. '4'.

Table 2

No description provided.


Antiproton-proton elastic scattering at 4 GeV/c and derivation of diffraction slope at infinite energy

Czyzewski, O. ; Escoubes, B. ; Goldscmidt-Clermont, Y. ; et al.
Phys.Lett. 15 (1965) 188-191, 1965.
Inspire Record 1392865 DOI 10.17182/hepdata.837

None

4 data tables
Table 1

'1'. '2'.

Table 3

No description provided.

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Charged Particle Multiplicity Distributions in Proton Anti-proton Collisions at 540-{GeV} Center-of-mass Energy

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 123 (1983) 108-114, 1983.
Inspire Record 182553 DOI 10.17182/hepdata.30779

Results on charged particle production in pp̄ collision at s 1 2 = 540 GeV are presented. The data were obtained at the CERN pp̄ collider using the UA1 detector, operated without magnetic field. The central particle density is 3.3 + - 0.2 per unit o pseudo-rapidity for non-diffractive events. KNO scaling of the multiplicity distributions withresults from ISR energies is observed.

6 data tables
Table 1

Pseudorapidity density distribution for all charged multiplicities corrected for acceptance and backgrounds by excluding NSD events. Data have been read from the plot.

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