An estimate of the long-distance effects in the KL-KS mass difference

1984 ◽  
Vol 148 (1-3) ◽  
pp. 205-210 ◽  
Author(s):  
I.I. Bigi ◽  
A.I. Sanda
2001 ◽  
Vol 16 (09) ◽  
pp. 1605-1630 ◽  
Author(s):  
K. TERASAKI

K→ππ, KL-KS mass difference (Δ mK) and KL→γγ(*) are studied systematically by decomposing their amplitude into a sum of factorizable and nonfactorizable ones. The former is calculated by using the naive factorization while the latter is assumed to be controlled by hadron dynamics. Nonfactorizable amplitudes for the K→ππ decays which are estimated by using a hard pion technique dominates the |ΔI| = ½ amplitude. It is seen that the naively factorized short distance term dominates ΔmK as usual since contributions of pseudoscalar-meson poles and ππ intermediate states as the nonfactorizable long distance effects interfere destructively with each other. The K*-meson pole survives in the KL→γγ decay and plays an important role in the present perspective in contrast with the existing theories which are restricted by the theory of field algebra. The form factor for the Dalitz decays of KL and their rates are compared with the existing data.


1990 ◽  
Vol 05 (19) ◽  
pp. 1477-1483 ◽  
Author(s):  
K. TERASAKI ◽  
S. ONEDA

It is argued that the asymptotic behavior of the matrix elements of Hw involving on-mass-shell ground-state mesons with infinite momenta, which were instrumental in explaining the |ΔI|=1/2 rule in the K→ππ decays, actually implies [Formula: see text]. The long distance effects (contributions of PS and vector meson poles and ππ intermediate states) may reproduce the observed KL−Ks mass difference, consistent with the |ΔI|=1/2 rule. Its estimate is however sensitive to the η-η′-… mixing.


1992 ◽  
Vol 07 (34) ◽  
pp. 3155-3160 ◽  
Author(s):  
K. TERASAKI ◽  
S. ONEDA

We estimate the fractional contribution of the Penguin term to the most important asymptotic ground state meson matrix elements of H w by fitting the calculated KS→π+π− decay rate and KL-KS mass difference to their observed values and show that the Penguin contribution does not play a dominant role for the |Δ I | = ½ rule. We then discuss long distance effects on the CP violation in the [Formula: see text] mixing by using the estimated fraction.


1990 ◽  
Vol 42 (1) ◽  
pp. 118-125 ◽  
Author(s):  
B. Machet ◽  
N. F. Nasrallah ◽  
K. Schilcher

2018 ◽  
Vol 33 (32) ◽  
pp. 1850194
Author(s):  
Aritra Biswas ◽  
Sanjoy Mandal ◽  
Nita Sinha

We show that for a heavy vector-like quark model with a down type isosinglet, branching ratio for [Formula: see text] decay is enhanced by more than [Formula: see text] as compared to that in the Standard model when QCD corrections to next-to-leading order are incorporated. In a left–right symmetric model (LRSM) along with a heavy vector-like fermion, enhancement of this order can be achieved at the bare (QCD uncorrected) level itself. We propose that a measurement of the photon polarization could be used to signal the presence of such new physics in spite of the large long distance effects. We find that there is a large region within the allowed parameter space of the model with a vector-like quark and an additional left–right symmetry, where, the photon polarization can be dominantly right-handed.


1995 ◽  
Vol 438 (1-2) ◽  
pp. 17-53 ◽  
Author(s):  
Roger Decker ◽  
Markus Finkemeier

2012 ◽  
Vol 27 (22) ◽  
pp. 1250125 ◽  
Author(s):  
GULSHEEN AHUJA ◽  
ROHIT VERMA ◽  
PRIYANKA FAKAY ◽  
P. S. GILL ◽  
MANMOHAN GUPTA

Recently several developments have taken place in the lattice QCD calculations of hadronic factors in the case of [Formula: see text] and the [Formula: see text] mixings along with contribution of the long distance effects in the [Formula: see text] system. These have led some authors (Refs. 12 and 13) to point towards the possibility of New Physics (NP) in these systems to the tune of 20% or so. However, the present analysis, based on essentially NP free inputs and incorporating constraints of unitarity, shows that in case the NP effects are there in the parameters associated with these systems, e.g. sin 2β, Vtd, ϵK, etc., these seem to be only at a few percent level.


1988 ◽  
Vol 41 (2) ◽  
pp. 327-331 ◽  
Author(s):  
T. N. Pham ◽  
D. G. Sutherland

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