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Explore the manifestation of chiral imbalance in hadron matter, from initial stages to hadronization. Discover new trends in chiral charge generation and the impact of chiral chemical potential on scalar and vector state lagrangians. Learn about direct observables of CP parity breaking and how to measure them. Dive into the induced chiral imbalance and its effects post heavy ion collisions. Investigate asymmetry comparisons and alternative methods to measure chiral imbalance in noncentral collisions. Predictions include enhancements in scalar resonances and modifications in meson dispersion laws. Unveil observables sensitive to P-odd polarization effects and their significance in heavy ion collision experiments.
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NSQCD2018, PNPI, Gatchina, 6.August 2018 Chiral imbalance: its manifestation in hadron matter A.A.Andrianov & V.A. Andrianov & D.Espriu Saint-Petersburg State University • Chiral charge generation: new trends • From initial stage to hadronization: chiral imbalance vacuum • Effective scalar and vector state lagrangians • with chiral chemical potential • 4. Direct observables of P(CP) parity breaking without E.-M. background • 5. Shall / can we measure them?
Our talk is dedicated to Lev N. Lipatov , the outstanding scientist and our good friend Highlights from the III Russian-Spanish congress (Santiago de Compostela, Spain, 2015) which was established by us together with L.N.Lipatov in 2011
In search for local parity breaking in heavy ion collisions , J.Bjorken DETECTION: scalar and vector meson masses depending on their polarizations, exotic decays A.A., V,A.Andrianov, D.Espriu, X.Planells, Phys. Lett. B 710 (2012) 230, Phys. Rev. D, 90 (2014), 034024) + A.Putilova, A.Iakubovich, Polarization asymmetry in pion-gamma production M. Kawaguchi,M. Harada,S. Matsuzaki,R. Ouyang , PHYS. REV. C 95, 065204 (2017)……..(generalization in this talk)
Induced chiral Imbalance Chiral imbalance
Birth of chiral imbalance Initial Stage After HI collision CI generation QGP Hadronization: hadron phase with chiral imbalance inherited from quark-gluon fireball < 1 fm/c 1 fm/c < 7-10 fm/c Quark-hadron continuity (T. Schaefer and F. Wilczek, Phys. Rev. Lett.82, 3956(1999); M.G. Alford,G. Baym,K. Fukushima,T. Hatsuda,and M. Tachibana, 1803.05115[hep-ph])
Noncentral HI collisions McLerran, Fukushima, Warringa; Voloshin….]
Asymmetry comparison: STAR vs. PHENIX: different centralities Thus to reduce uncertainties one must find alternative ways to measure chiral imbalance
How to “measure” parity odd effects theoretically? Chiral chemical potential/chiral flow vector Vector mesons Fermions Scalars? Split transversal polarizations in masses Split positive and negative fermion helicities in masses = 0 A.A., P.Giacconi, R.Soldati, JHEP02(2002)030
A. A. Andrianov, V. A. Andrianov, D. Espriu,A. E. Putilova, A. V. Iakubovich SCALARS QCD inspired effective meson lagrangian (SU(2) case) current quark mass pions scalar mesons (isosingles + isotriplets) Chiral chemical potential = time-component of axial field
Masses with chiral imbalance < 0 but no instability! When “tachyon” in flight
Mixing of scalars and pseudoscalars and their decays ( depending on velocity ) k = 0 k = 1000 MeV
Exotic decays with chiral imbalance: P-even vertices A. A. Andrianov, V. A. Andrianov, D. Espriu,A. E. Putilova, A. V. Iakubovich
M. Kawaguchi,M. Harada,S. Matsuzaki,R. Ouyang , PHYS. REV. C 95, 065204 (2017)
M. Kawaguchi,M. Harada,S. Matsuzaki,R. Ouyang , PHYS. REV. C 95, 065204 (2017) Our prediction: Scalar resonance enhancement!
More details in A.A., V.A. Andrianov’s, D. Espriu and X.Planells, Phys. Lett. B 684(2010) 101; B 710 (2012) 230,…
Unfortunately the splitting is strongly contaminated by thermal effects
Thus arises the question. Can these polarization effects somehow be registered in the experiments with heavy ion collisions and thereby assert about the existence of the local parity breaking phase? (details see A.A. Andrianov, V. A. Andrianov, D. Espriu, and X. Planells, Phys. Rev. D, 90 (2014), 034024).
We proposeobservables sensitive to P-oddpolarization effects We study the angular distributions for the polarizations in the mentioned reactions when the angle between the two outgoing leptons in the decay of meson constrained with the laboratory frame. In orderto select the transverse polarizations in the spectrum, we will perform the different cuts for each angle and study the variations of the \rho (and \omega)- spectral function.
Conclusions and outlook • Topological charge fluctuations transmit their influence from QGP to hadron physics via axial chemical potential: in this way local parity breaking (LPB) occurs in hadron sector • 2. LPB enhances dynamical chiral symmetry breaking in QCD: • chiral condensates are increasing with chiral chemical potential • Axial chemical potential triggers parity-odd condensation for large baryon chemical potential in first-order phase transitions (“chiral catalysis” V.Braguta et al.) • 4. LPB modifies dispersion laws for scalar and vector mesons: • lightest “pseudoscalar” mesons tend to massless states in flight, vector meson polarizations split with different in-flight masses • There are observables unambiguously indicating LPB • (STAR, ALICE LHC?): exotic scalar/pseudoscalar meson decays, mass splitting of vector mesons, quarks/nucleons etc.