Towards the (Mexican) discovery of 2nd class currents @ Belle-II - PowerPoint PPT Presentation

XV MEXICAN WORKSHOP ON PARTICLES AND FIELDS Mazatlán (Sinaloa) 2-6 November 2015 Towards the (Mexican) discovery of 2nd class currents @ Belle-II Pablo Roig Dpto. de Física Cinvestav-IPN México DF Collaboration with R. Escribano and S. González-Solís (IFAE & UAB, Barcelona), to appear soon

CONTENTS MOTIVATION Relation between pp , ph , ph ’ VFFs Relation between KK , ph , ph ’ SFFs CONCLUSIONS Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

MOTIVATION Non-strange V-A currents can be split into 1st class currents: 2nd class current: SCC Irrespective of the underlying resonance mechanism Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

MOTIVATION Non-strange V-A currents can be split into 1st class currents: 2nd class current: SCC Irrespective of the underlying resonance mechanism Note: There are/have been several attempts to discover SCC in nuclear processes, but they mostly rely on CVC (and SCC should be effects of the order of isospin breaking corrections to CVC) and have large uncertainties. RevModPhys.78.991 Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

MOTIVATION SCC Irrespective of the underlying resonance mechanism These decay modes should have already been discovered if it was not for the strong bkg Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

MOTIVATION SCC Irrespective of the underlying resonance mechanism These decay modes should have already been discovered if it was not for the strong bkg τ −→ ηπ − π 0 ν τ Dumm & Roig Phys.Rev. D86 (2012) 076009 Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

MOTIVATION SCC Irrespective of the underlying resonance mechanism The considered processes could provide complementary information to h 3 p Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

MOTIVATION SCC Irrespective of the underlying resonance mechanism The considered processes could provide complementary information to h 3 p The corresponding suppression of the SM contribution can make NP visible Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

MOTIVATION Enhancement of the dominating SFF: From B tn t Improvable if we know the SFF with < 20% accuracy Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Following Gasser & Leutwyler: Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Following Gasser & Leutwyler: Another FF (F 0 ) is employed instead of F - in order to have both FFs in correspondence with S- (F 0 ) and P-wave (F + ). Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Following Gasser & Leutwyler: Another FF (F 0 ) is employed instead of F - in order to have both FFs in correspondence with S- (F 0 ) and P-wave (F + ). ∂ m Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Following Gasser & Leutwyler: Another FF (F 0 ) is employed instead of F - in order to have both FFs in correspondence with S- (F 0 ) and P-wave (F + ). ∂ m ∂ m Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

All dynamics is encoded in the normalized FFs (Erler) Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

All dynamics is encoded in the normalized FFs (Erler) Isospin-violating quantity explaining the overall suppression of these decays Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between pp , ph , ph ’ VFFs c PT in the large-N C limit: simultaneous expansion in p 2 , m 2 and 1/N C Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between pp , ph , ph ’ VFFs c PT in the large-N C limit: simultaneous expansion in p 2 , m 2 and 1/N C Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between pp , ph , ph ’ VFFs c PT in the large-N C limit: simultaneous expansion in p 2 , m 2 and 1/N C Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Data-driven ph & ph ’ VFFs Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs In previous works we showed that a Breit-Wigner description of SFFs fails to account for the data in t  K( p / h ) n t decays. Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs In previous works we showed that a Breit-Wigner description of SFFs fails to account for the data in t  K( p / h ) n t decays. This is not surprising since BWs violate analyticity and unitarity and do not comply with chiral symmetry requirements. Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs In previous works we showed that a Breit-Wigner description of SFFs fails to account for the data in t  K( p / h ) n t decays. This is not surprising since BWs violate analyticity and unitarity and do not comply with chiral symmetry requirements. Although theory says BWs should not be applied, sometimes they are an easy solution fo the experimentalists. Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs In previous works we showed that a Breit-Wigner description of SFFs fails to account for the data in t  K( p / h ) n t decays. This is not surprising since BWs violate analyticity and unitarity and do not comply with chiral symmetry requirements. Although theory says BWs should not be applied, sometimes they are an easy solution fo the experimentalists. That is why we decided to start our analyses with them (again). Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs (Brodsky-Lepage) Real part of the loop neglected Violation of analyticity Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs We have also considered a two-resonance BW SFF Now both normalized FFs differ! Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Errors known, correlations unknown! Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs (Brodsky-Lepage) Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Very different normalized FFs! Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs ‘traditional’ iterative solution Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Closed-form solution A closed-form solution is much less time- consuming than the „traditional‟ iterative method, which is great for fits and MC generators (TAUOLA) O. Shekhovtsova , T. Przedzinski, P. Roig & Z. Was. Phys.Rev. D86 (2012) 113008 Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Closed-form solution Crucial coupled channels corrections! Very different normalized FFs! Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Closed-form solution We can also consider coupling ph & ph ’ to KK Crucial coupled channels corrections! Strong effect of coupling to KK! a 0 (980) as KK molecule or tetraquark Very different normalized FFs! Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Straightforward generalization of 2-coupled channels case (closed-form solution) Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Relation between KK , ph , ph ’ SFFs Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Errors due to p - h - h ’ mixing Towards the discovery of 2nd class currents @ Belle-II Pablo Roig

Meaningless uncorrelated error analysis Towards the discovery of 2nd class currents @ Belle-II Pablo Roig