First observation of pi0 production in the reaction d + d ---> alpha + pi0, prohibited by charge symmetry conservation and measurement of the reaction d + d ---> alpha + gamma

Goldzahl, L.; Banaigs, J.; Berger, J.; Fabbri, F.; Hufner, J.; Satta, L.

doi:10.1016/0375-9474(91)90540-M

First observation of pi0 production in the reaction d + d ---> alpha + pi0, prohibited by charge symmetry conservation and measurement of the reaction d + d ---> alpha + gamma

Jun 13, 1991

37 pages

Published in:

Nucl.Phys.A 533 (1991) 675-711

Published: 1991

DOI:

10.1016/0375-9474(91)90540-M

Report number:

LAPP-EXP-91-03

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Abstract: (Elsevier)

The reaction d+d→ α + π 0 which is in clear violation of charge symmetry conservation, has been observed for the first time at a laboratory energy of 1.10 GeV in an experiment carried out at the Saturne synchroton at Saclay. The number of π 0 's detected corresponds to a differential cross section d σ d Ω ∗ (π 0 ) = 0.97 ± 0.20 ± 0.15 pb/sr at a centre-of-mass angle of θ c . m . = 107°, where the first error bar refers to the statistical uncertainty and the second to the systematic. The reaction d+d→ α + γ was measured simultaneously with the π 0 production, leading to a differential cross section of d σ d Ω ∗ (γ) = 0.82±0.18±0.10 pb/sr at the slightly larger angle of θ c . m . = 110°. The available predictions of theoretical models of charge symmetry breaking, based upon η / π mixing, fall an order of magnitude below our measurement. However, these predictions for the η / π mixing level might be boosted by the η threshold (1.121 GeV) proximity, where this experiment is performed.

Nuclear Reactions
deuteron deuteron: exclusive reaction
deuteron deuteron: nuclear reaction
helium: hadroproduction
hadroproduction: helium
pi0: hadroproduction
hadroproduction: pi0
photon: hadroproduction
hadroproduction: photon
charge: symmetry breaking

References(24)

Figures(0)

[1]

E.M. Henley
,
G.A. Miller

- Mesons and Nuclei vol.I (1979) 405

[2]

Measurement of the Neutron Neutron Scattering Length A( $N N$ ) With the Reaction $\pi^- D \to N N \gamma$ in Complete Kinematics

et al.

- Phys.Rev.C 35 (1987) 2252-2257,
- Phys. Rev. C35 ( 1987) 2252-2257
•
DOI:
- 10.1103/PhysRevC.35.2252

[3]

A Study of Charge Independence and Symmetry from pi+ and pi- Total Cross-Sections on Hydrogen and Deuterium Near the 3,3 Resonance

et al.

- Nucl.Phys.A 300 (1978) 321-347,
- In *Ericson, T.E.O. et al.: The meson factories* 287-311
•
DOI:
- 10.1016/0375-9474(78)96136-5

[3]

CHARGE SYMMETRY IN PION DEUTERON ELASTIC SCATTERING

et al.

- Phys.Rev.C 30 (1984) 2010-2021,
- Phys. Rev. C30 ( 1984) 2010-2021
•
DOI:
- 10.1103/PhysRevC.30.2010

[4]

Test of Charge Symmetry in Neutron - Proton Elastic Scattering at 477-{MeV}

et al.

- Phys.Rev.Lett. 56 (1986) 2571,
- In *Ericson, T.E.O. et al.: The meson factories* 369-372, and Phys. Rev. Lett. 56 (1986) 2571-2574
•
DOI:
- 10.1103/PhysRevLett.56.2571

[5]

Charge Symmetry Breaking in the Reaction $n p \to d \pi^0$

Jouni A. Niskanen
(
- Adelaide U.
)
,
M. Sebestyen
(
- Adelaide U.
)
,
Anthony William Thomas
(
- Adelaide U.
)

- Phys.Rev.C 38 (1988) 838-845
•
DOI:
- 10.1103/PhysRevC.38.838

[6]

L.I. Lapidus

- Sov.Phys.JETP 4 (1957) 740

[7]

Test of Isotopic Spin Conservation from an Experiment Limit on sigma (d+d --> He-4 + pi0)

John A. Poirier
(
- UC, Berkeley
)
,
Morris Pripstein
(
- UC, Berkeley
)

- Phys.Rev. 122 (1961) 1917-1918
•
DOI:
- 10.1103/PhysRev.122.1917

[7]

J.A. Poirier
,
M. Pripstein

- Phys.Rev. 130 (1963) 1171

[7]

Akimov
,
Yu.K.

- Sov.Phys.(JETP) 14 (1969) 512

[8]

Experimental Test of Charge Symmetry in Strong Interactions Through the Reaction d d ---> He-4 pi0

et al.

- Phys.Lett.B 53 (1974) 390-392
•
DOI:
- 10.1016/0370-2693(74)90411-0

[9]

Search for the Charge Symmetry Breaking Reaction $D D \to ^{4}$ He $\pi^0$ at 0.8-{GeV}

et al.

- Phys.Rev.Lett. 58 (1987) 1922-1925,
- Phys. Rev. Lett. 58 ( 1987) 1922-1925
•
DOI:
- 10.1103/PhysRevLett.58.1922

[10]

Production of I = 0 Mesonic States in the Reaction d d --> He-4 x

et al.

- Nucl.Phys.B 105 (1976) 52
•
DOI:
- 10.1016/0550-3213(76)90060-2

[10]

ELASTIC SCATTERING OF POLARIZED DEUTERONS BY PROTONS AT INTERMEDIATE-ENERGIES

et al.

- Nucl.Phys.A 431 (1984) 613-636,
- Nucl. Phys. A431 ( 1984) 613-636
•
DOI:
- 10.1016/0375-9474(84)90272-0

[10]

FIRST OBSERVATION OF THE D + D ---> HE-4 + ETA0 REACTION

et al.

- Phys.Rev.C 32 (1985) 1448-1449,
- Phys. Rev. C32 ( 1985) 1448-1449
•
DOI:
- 10.1103/PhysRevC.32.1448

[11]

programme sur le système SAR du LNS de Saclay

[12]

rapport interne LNS

P. Fleury
,
F. Plouin

[13]

Identification of the $D + P \to ^{3}$ He + $\eta$ Reaction Very Near Threshold: Cross-section and Deuteron Tensor Analyzing Power

et al.

- Phys.Rev.Lett. 61 (1988) 919-922
•
DOI:
- 10.1103/PhysRevLett.61.919

[14]

communication particuliére

C. Wilkin

[15]

$\pi^0 \eta$ and $\pi^0 \eta^\prime$ Mixing and the Reaction $D + D \to \pi^0 + ^{4}$ He

S.A. Coon
(
- Arizona U.
)
,
B.M. Preedom
(
- South Carolina U.
)

- Phys.Rev.C 33 (1986) 605-607,
- Phys. Rev. C33 ( 1986) 605-607
•
DOI:
- 10.1103/PhysRevC.33.605

[16]

Gluon Effects in Isospin Violating Meson Mixings

C.Y. Cheung
(
- TRIUMF
)

- Phys.Lett.B 138 (1984) 245-248
•
DOI:
- 10.1016/0370-2693(84)91650-2

[17]

Experimental Investigation of the He-4 (gamma d) d Reaction

et al.

- Phys.Lett.B 62 (1976) 411-412
•
DOI:
- 10.1016/0370-2693(76)90671-7

[18]

d d ---> He-4 gamma CROSS-SECTION MEASUREMENT AT 376-MeV

B.H. Silverman
(
- UCLA and
- Saclay
)
,
A. Boudard
(
- UCLA and
- Saclay
)
,
W.J. Briscoe
(
- UCLA and
- Saclay
)
,
G. Bruge
(
- UCLA and
- Saclay
)
,
P. Couvert
(
- UCLA and
- Saclay
)

et al.

- Phys.Rev.C 29 (1984) 35,
- Phys. Rev. C29 ( 1984) 35-39 and Calif. Univ. Los Angeles - UCLA-10P025-79 (REC.SEP.82) 13p
•
DOI:
- 10.1103/PhysRevC.29.35

[19]

Identification and analysis of the n p ---> d eta cross-section near threshold

F. Plouin
(
- Saclay
)
,
P. Fleury
(
- Saclay
)
,
Colin Wilkin
(
- University Coll. London
)

- Phys.Rev.Lett. 65 (1990) 690-693
•
DOI:
- 10.1103/PhysRevLett.65.690