PBAR P --> NBAR N
Max results
Sort by Reverse order

Showing 10 of 23 results

Studies of $\bar{p} p \to \bar{n} n$ and $\bar{n} p$ Annihilation at Incident Momenta of 700-{MeV}/$c$ and 760-{MeV}/$c$

The Bombay-Chandigarh-Jammu-Tokyo collaboration Banerjee, S. ; Ganguli, S.N. ; Gurtu, A. ; et al.
Z.Phys.C 28 (1985) 163, 1985.
Inspire Record 217418 DOI 10.17182/hepdata.1974

Results are presented on the charge exchange reaction\(\bar pp \to \bar nn\) and\(\bar np\) annihilations from bubble chamber exposures to antiproton beam of momenta 700 and 760 MeV/c. The differential cross section of\(\bar pp \to \bar nn\) shows a forward spike followed by a clear dip bump structure. Total annihilation cross section of\(\bar np\) for average\(\bar n\) momentum of 700 MeV/c has been evaluated to be 55.4±2.2 mb. The multiplicity, Feynmanx andpT2 distributions for inclusive charged pions in\(\bar pp\) and\(\bar np\) annihilations are found to be similar. The emission of charged pions from\(\bar np\) annihilations are found to be consistent with thermodynamic models with temperature ∼110 MeV.

11 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

First measurement of the spin transfer parameter K(n00n) in the anti-p p ---> anti-n n reaction at 875-MeV/c

Ahmidouch, A. ; Bertini, R. ; Birsa, R. ; et al.
Phys.Lett.B 380 (1996) 235-240, 1996.
Inspire Record 429760 DOI 10.17182/hepdata.5745

The spin-transfer parameter K n 00 n of the p p↑ → n ↑n charge exchange reaction has been measured for the first time at the CERN Low Energy Antiproton Ring (LEAR), at 875 MeV/ c p momentum, in the centre-of-mass scattering-angle range from 45° to 78°. To measure the transverse polarisation of the n 's, a thick scintillator counter hodoscope was used as live target, and the elastic n p scattering on the hydrogen of the scintillator was used as analysing reaction of the n transverse polarisation. Its so far unmeasured analysing power is taken as linear in momentum transfer, A n p = α·q , and results are given for α · K n 00 n . The values one obtains for K n 00 n , estimating α from N N potential models, are less than 0.25, in agreement with the predictions.

2 data tables
Table 1

Polarized beam. CONST is overall normalization unknown factor.

Table 2

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.

More…

Measurement of the analyzing power and the differential cross-section of the anti-p p charge exchange reaction at LEAR

Birsa, R. ; Bradamante, F. ; Dalla Torre-Colautti, S. ; et al.
Phys.Lett.B 246 (1990) 267-272, 1990.
Inspire Record 296501 DOI 10.17182/hepdata.29676

As part of a programme to study the spin structure of the p p→ n n channel, we have measured the analysing power A 0 n and the differential cross section at an incident antiproton beam momentum of 704 MeV/ c . The analysing power exhibits a remarkable angular dependence, which is poorly reproduced by the existing potential models.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


The total and differential cross-sections for the reaction anti-p + p ---> anti-n + n at 1.13 gev/c

Colebourne, A. ; Donald, R.A. ; Edwards, D.N. ; et al.
Nucl.Phys.B 70 (1974) 205-214, 1974.
Inspire Record 94753 DOI 10.17182/hepdata.32347

The reaction p ̄ p → n ̄ n has been studied at an incident antiproton laboratory momentum of 1.13 GeV/ c . The antineutron was identified through a subsequent annihilation on a proton. In all, 2601 identified events were obtained. Total and differential cross sections are presented. Comparison is made with the predictions of the Bryan and Phillips model which, in this energy range, is succesful in describing the related reaction p ̄ p → p ̄ p . Here, the agreement is less good.

1 data table
Table 1

No description provided.


Anti-proton charge exchange on protons at 25 and 35 gev/c

Bolotov, V.N. ; Isakov, V.V. ; Kakauridze, D.B. ; et al.
Nucl.Phys.B 73 (1974) 401-409, 1974.
Inspire Record 94654 DOI 10.17182/hepdata.32275

Cross sections for p ̄ p → n ̄ n at 25 and 35 GeV/ c have been measured. The cross sections decrease with increasing momentum as 1/ P 2 . A narrow peak is observed in the momentum transfer interval 0 ⩽ − t ≲ 0.02 (GeV/ c 2 in the differential cross sections. Neither ϱ nor A 2 exchange contribute to the process in the investigated energy range.

3 data tables
Table 1

K- CEX MEASURED BY STARS FROM KL AS A CHECK.

Table 2

No description provided.

Table 3

No description provided.


Measurement of the anti-p p Charge Exchange Cross-Section Below 1-GeV/c

Alston-Garnjost, M. ; Kenney, R. ; Pollard, D. ; et al.
Phys.Rev.Lett. 35 (1975) 1685, 1975.
Inspire Record 99503 DOI 10.17182/hepdata.21220

No definite evidence for structure is found in the p¯p→n¯n cross section between 276 and 963 MeV/c. From these results limits are deduced on properties of the narrow enhancement reported in the p¯p total cross section at 475 MeV/c.

1 data table
Table 1

No description provided.


High precision measurement of the $\overline{p}p \to \overline{n}n$ charge exchange differential cross-section

Birsa, R. ; Bradamante, F. ; Bressan, A. ; et al.
Phys.Lett.B 339 (1994) 325-331, 1997.
Inspire Record 382031 DOI 10.17182/hepdata.27114

The differential p p → n n charge-exchange cross section has been measured at the CERN Low Energy Antiproton Ring (LEAR), at two incident p momenta, 601 and 1202 MeV/c. features of the differential cross-section near the forward direction, i.e. a sharp peak at 0° scattering angle followed by an energy dependent dip-bump structure, are confirmed and measured with good precision and high statistical accuracy. The data show very clearly that the shape of the cross-section is a manifestation of the pion-exchange amplitude, and a simple extrapolation to the pion pole already indicates that the pion-nucleon coupling constant f c 2 can be determined with good precision.

2 data tables
Table 1

No description provided.

Table 2

Corrected with data from PL B405,389.


Charge exchange anti-p p ---> anti-n n differential cross-sections between 546-MeV/c and 1287-MeV/c

Ahmidouch, A. ; Heer, E. ; Hess, R. ; et al.
Phys.Lett.B 364 (1995) 116-120, 1995.
Inspire Record 407478 DOI 10.17182/hepdata.28461

The differential cross section of the charge-exchange reaction p p → n n has been measured at the CERN Low Energy Antiproton Ring (LEAR) at seven p momenta in the range 546–1287 MeV/ c . A pentanol polarized target has been used and the neutron and the antineutron have been detected in coincidence. The data cover most of the angular range.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

First measurement of the depolarization parameter D(onon) of the anti-p p ---> anti-n n charge exchange reaction

Birsa, R. ; Bradamante, F. ; Bressan, A. ; et al.
Phys.Lett.B 302 (1993) 517-522, 1993.
Inspire Record 354498 DOI 10.17182/hepdata.28944

The depolarization parameter D 0 n 0 n in the charge-exchange reaction p p ↑→ n n ↑ has been measured for the first time at the CERN Low Energy Antiproton Ring (LEAR) at 875 MeV/ c antiproton beam momentum, in the forward hemisphere. The measured values of D 0 n 0 n are always smaller than ±0.3, indicating that the two-spin amplitudes dominate the scattering matrix as suggested by the meson exchange potential models.

1 data table
Table 1

No description provided.