Angular-correlation and branching-ratio studies ofCa41with theCa40(d,pγ)Ca41reaction

L. C. McIntyre

doi:10.1103/physrevc.9.200

PROPERTIES OF THE 7.02-MeV AND 10.65-MeV LEVELS OF 20Ne

Canadian Journal of Physics ◽

10.1139/p67-168 ◽

1967 ◽

Vol 45 (6) ◽

pp. 2133-2143 ◽

Cited By ~ 5

Author(s):

P. J. M. Smulders ◽

C. Broude ◽

A. E. Litherland

Keyword(s):

Angular Correlation ◽

Excellent Agreement ◽

Amplitude Ratio ◽

Branching Ratio ◽

Rotational Model ◽

Particle Counter ◽

Correlation Techniques

The 7.02-MeV level of 20Ne has been studied by the I2C(12C, αγ)20Ne reaction, using angular correlation techniques, with a particle counter and six Nal crystals. The spin and parity of this level were determined to be 4−. The branching ratio of the decays to the 5.63, 4.97, and 4.25 MeV levels was found to be 22:65:13. The transition to the 5.63-MeV state (4− → 3−) is an almost pure E2 transition with an M1/E2 amplitude ratio of 0.03 ± 0.03. The branching ratio of the E2 transitions to the 5.63-MeV 3− level and the 4.97-MeV 2− level is in excellent agreement with predictions from the rotational model and also with SU3 calculations.Similar measurements on the 10.65-MeV level in 20Ne support the tentative 6− assignment to this level.

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THE CP-VIOLATING ASYMMETRY IN η → π+ π-e+e-

Modern Physics Letters A ◽

10.1142/s0217732302007739 ◽

2002 ◽

Vol 17 (24) ◽

pp. 1583-1588 ◽

Cited By ~ 20

Author(s):

DAO-NENG GAO

Keyword(s):

Angular Correlation ◽

Upper Bound ◽

Branching Ratio ◽

Type Operator ◽

Cp Asymmetry ◽

The Future ◽

The Asymmetry ◽

O 10 ◽

Magnetic Amplitude

We study the CP-violating asymmetry [Formula: see text], which arises, in η → π+π-e+e-, from the angular correlation of the e+e- and π+ π- planes due to the interference between the magnetic and electric decay amplitudes. With the phenomenologically determined magnetic amplitude and branching ratio as input, the asymmetry, induced by the electric bremsstrahlung amplitude through the CP-violating decay η → π+π-, and by an unconventional tensor type operator, has been estimated respectively. The upper bound of [Formula: see text] from the former is about 10-3, and the asymmetry from the latter might be up to O(10-2). One can therefore expect that this CP asymmetry would be an interesting CP-violating observable for the future precise measurements in the η factories.

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Confirmation of the existence of the X17 particle

EPJ Web of Conferences ◽

10.1051/epjconf/202023204005 ◽

2020 ◽

Vol 232 ◽

pp. 04005 ◽

Cited By ~ 2

Author(s):

D. S. Firak ◽

A. J. Krasznahorkay ◽

M. Csatlós ◽

L. Csige ◽

J. Gulyás ◽

...

Keyword(s):

Excited State ◽

Angular Correlation ◽

Branching Ratio ◽

Pair Creation ◽

Subsequent Decay ◽

The Creation

In a 2016 paper, an anomaly in the internal pair creation on the M1 transition depopulating the 18.15 MeV isoscalar 1+ state on 8Be was observed. This could be explained by the creation and subsequent decay of a new boson, with mass mXc2 = 16.70 MeV. Further experiments of the same transition with an improved and independent setup were performed, which constrained the mass of the X17 boson (mXc2) and its branching ratio relative to the γ-decay of the 8Be excited state (BX), to mXc2 = 17.01(16) MeV and BX = 6(1) 10−6, respectively. Using the latter setup, the e+e− pairs depopulating the 21 MeV Jπ = 0− 0+ transition in 4He were investigated and a resonance in the angular correlation of the pairs was observed, which could be explained by the same X17 particle, with mass mXc2 = 16.98 ± 0.16(stat) ± 0.20(syst) MeV.

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