Alternative Form of the Parity-Violating Current for the Hyperon Weak Radiative Decays and Hara Theorem

نویسندگان

  • Elena N. Bukina
  • Vladimir M. Dubovik
  • Valery S. Zamiralov
چکیده

It is shown that upon considering an alternative form of a parity-violating part of the transition electromagnetic current it is possible to reformulate Hara theorem in a way that it does not forbid any more nonzero asymmetry in the hyperon weak radiative decays Σ+ → p + γ and Ξ− → Σ− + γ in the limit of exact SU(3)f symmetry thus resolving a contradiction with the data and maybe revealing hitherto unseen transition toroid dipole moments. A result is consistent with the traditional one on the single-quark weak radiative transition models. We have also reproduced Vasanti formula at the quark level. As for two-quark weak radiative transitions we have found that the important part of it contains also a toroid dipole moment contribution which seems to be an intrinsic reason of the apparent contradiction between the Hara theorem conclusion and quark model results for hyperon weak radiative decays. PACS number(s): 11.30.Hv, 13.30.-a, 13.40.Hg, 14.20.Jn

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Weak Radiative Hyperon Decays

It is shown that an alternative form of the parity-nonconserving (PNC) transition electromagnetic current resolves partly a puzzle with the Hara theorem. New formulation of it has allowed PNC weak radiative hyperon transitions of the charged hyperons Σ+ ⇒ p + γ and Ξ ⇒ Σ + γ revealing hitherto unseen transition toroid dipole moment.

متن کامل

Hara Theorem, GIM Model, and Asymmetry in Weak Radiative Hyperon Decays

It is shown that in the framework of GIM model, the parity-violating (PV) Σ+(uus) ⇒ p(uud) + γ decay amplitude does not vanish but just transforms into another PV decay amplitude, namely, of the Ωcc(ccs) → Ξcc(ccd) + γ decay. The known result is used that the relevant part of the CP-invariant effective current× current Hamiltonian changes sign under simultaneous quark changes d ↔ s and u ↔ c. S...

متن کامل

ar X iv : h ep - p h / 01 07 07 6 v 1 9 Ju l 2 00 1 Electroweak Radiative Corrections to Parity - Violating Electroexcitation of the ∆

We analyze the degree to which parity-violating (PV) electroexcitation of the ∆(1232) resonance may be used to extract the weak neutral axial vector transition form factors. We find that the axial vector electroweak radiative corrections are large and theoretically uncertain, thereby modifying the nominal interpretation of the PV asymmetry in terms of the weak neutral form factors. We also show...

متن کامل

Resonances in radiative hyperon decays

The importance of resonances for the radiative hyperon decays is examined in the framework of chiral perturbation theory. Low lying baryon resonances are included into the effective theory and tree contributions to these decays are calculated. We find significant contributions to both the parity-conserving and parity-violating decay amplitudes and a large negative value for the asymmetry parame...

متن کامل

99 02 43 1 v 1 2 2 Fe b 19 99 Resonances in radiative hyperon decays

The importance of resonances for the radiative hyperon decays is examined in the framework of chiral perturbation theory. Low lying baryon resonances are included into the effective theory and tree contributions to these decays are calculated. We find significant contributions to both the parity-conserving and parity-violating decay amplitudes and a large negative value for the asymmetry parame...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 1999