1. Heavy flavor mesons in strong magnetic fields Michal Šumbera Nuclear Physics Institute AS CR, Řež/Prague Based on the presentation of Peter Filip at CPOD 2013 http://cpod2013.lbl.gov/scientific-program-1/scientific-talks/1130_Filip.pdf?attredirects=0&d=1 and Particle production in strong electromagnetic fields in relativistic heavy-ion collisions by Kirill Tuchin, arXiv:1301.0099 [hep-ph]arXiv:1301.0099 [hep-ph]

2. a To probe the extended topological gluon field configurations, it is beneficial to have a complementary probe - an external, coherent electromagnetic field. Because of the existence of quark zero modes and associated topology, the magnetic field is ideal. However, usually the available magnetic field is weak, leading to small corrections; but, not so if eB~Λ 2 QCD - available in heavy ion collisions! Why QCD in magnetic fields? B Peak magnetic field ~ 10 15 Tesla ! B  Reaction plane adapted from D. Kharzeev @ CPOD2013 Kharzeev, McLerran, Warringa, Nucl PhysA803(2008)227

3. Heavy ion collisions – source of the strongest magnetic fields Kharzeev, McLerran, Warringa, Nucl PhysA803(2008)227 Biot-Savarat law:

4. D. Kharzeev @ CPOD2013

5. Event-by-event generation of electromagnetic fields in heavy-ion collisions Wei-Tian Deng and Xu-Guang Huang, Phys.Rev. C85 (2012) 044907 Direct calculations of Liénard- Wiechert potentials using coordinates and velocities of incoming protons * from HIJING *Contributions from the produced partons to the generation of the EM field is neglected. The electromagnetic fields at t = 0 and r = 0 as functions of the impact parameter b Due to EbyE fluctuations ≈ ≈ ≠0

6. Wei-Tian Deng and Xu-Guang Huang Phys.Rev. C85 (2012) 044907 For a x ~ a y ~ 3 fm and c 2 s ~1/3, we see from Eqs. (4.23)-(4.24) that for t ≤ 5 fm the magnetic fields decay inversely proportional to time. However, if the produced matter, after a short early-stage evolution, is in the QGP phase, the electric conductivity σ is not negligible. Magnetic field evolution in the presence of QGP medium I Where a x and a y are parameters of Gaussian transverse entropy density profile:

7. Kirill Tuchin, arXiv:1301.0099 [hep-ph]arXiv:1301.0099 [hep-ph] Due to finite electrical conductivity of QGP, magnetic field essentially freezes in the plasma for as long as plasma exists!!!!! Magnetic field evolution in the presence of QGP medium II

8. L. McLerran, V. Skokov arXiv:1305.0774 [hep-ph] (May 3, 2013) In contrast to the results obtained in Ref. [7], we showed that the effects of conductivity do not play an important role for realistic values. Magnetic field for static medium with Ohmic conductivity, σ Ohm. Magnetic field evolution in the presence of QGP medium III

9. Experimental signatures of strong EM fields in heavy ion collisions

10. ALICE & STAR charge separation result Chiral Magnetic Effect - if it exists - contributes to the reaction plane dependent two-particle correlator, (α,β)=(±,±) [ALICE Collaboration], Phys.Rev.Lett. 110 (2013) 012301

11. S. Voloshin @ CPOD2013

12. Alternative explanations conservation of transverse momentum local charge conservation due to the presence of elliptic flow many other two-particle correlations enter all these corrections may be of the same order as the experimental signal  experimentally disentangle the elliptic flow phenomenon from the creation of a strong magnetic field A. Bzdak, V. Koch and J.Liao, Lect.Notes Phys.871, 503 (2013), arXiv:1207.7327 [nucl-th].

13. What other effects of strong EM fields are available in heavy ion collisions?

14. Adam Bzdak and Vladimir Skokov, Phys. Rev. Lett. 110, 192301 (2013), Anisotropy of photon production: Initial eccentricity or magnetic field Recent measurements of the azimuthal anisotropy of direct photons in heavy-ion collisions at the energies of RHIC (A. Adare et al. [PHENIX Collaboration], Phys. Rev. Lett. 104, 132301 (2010)) show that it is of the same order as the hadronic one. This finding appears to contradict the expected dominance of photon production from a quark-gluon plasma at an early stage of a heavy- ion collision. A possible explanation of the strong azimuthal anisotropy of the photons, given recently, is based on the presence of a large magnetic field in the early phase of a collision. In this letter, we propose a method to experimentally measure the degree to which a magnetic field in heavy-ion collisions is responsible for the observed anisotropy of photon production.

15. arXiv:1301.0099 [hep-ph] Particle production in strong electromagnetic fields in relativistic heavy-ion collisions Kirill Tuchin 1 1 Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (Dated: January 21, 2013) I review the origin and properties of electromagnetic fields produced in heavy ion collisions. The field strength immediately after a collision is proportional to the collision energy and reaches ~m π 2 at RHIC and ~10~m π 2 at LHC … …Very strong electromag- netic field has an important impact on particle production. I discuss the problem of energy loss and polarization of fast fermions due to synchrotron radiation, consider photon decay induced by magnetic field, elucidate J/ψ dissociation via Lorentz ionization mechanism and examine electromagnetic radiation by plasma. I conclude that all processes in QGP are affected by strong electromagnetic field and call for experimental investigation. Broad range of phenomena

16. Quarks and leptons are expected to be strongly polarized in plasma in the direction parallel or anti-parallel to the magnetic field depending on the sign of their electric charge. The synchrotron radiation alone is able to account for quenching of jets at LHC with p T as large as 20 GeV. Polarization of the final photon spectrum perpendicular to the field. At mid-rapidity the azimuthal asymmetry of the decay rate translates into asymmetric photon yield and contributes to the elliptic flow Finally, photon decay due to pair-production in external magnetic field leads to enhancement of dilepton yield. Magnetic field strongly modifies the azimuthal distribution of the produced J/ψ 's  Study dependence of quark jets, photons, dileptons and heavy quark mesons on Ψ R arXiv:1301.0099 [hep-ph] Broad range of phenomena

17. Another work on heavy quarkonia C.S. Machado et al.: Heavy quarkonium production in a strong magnetic field, arXiv:1305.3308 [hep-ph] (May 16, 2013) Investigate the effects of a strong magnetic field on B and D mesons, focusing on the changes of the energy levels and the masses of the bound states. The field induces a mass reduction of hydrogen-like heavy bound states, an effect which is mainly due to the coupling between the spin and the magnetic field. Using the Color Evaporation Model they discuss the possible changes in the production of J/ψ and Υ. Differential J/ψ (left) and Υ (right) production cross section at √s = 4.5 TeV

18. arXiv:1301.0099 [hep-ph] Particle production in strong electromagnetic elds in relativistic heavy-ion collisions Kirill Tuchin 1 …

20.  +   Mixing in [B]: for B=0 c 2 = s 2 = 1/2 in [B] orto-Ps (J=1) and para-Ps (J=0) states {m z = 0} get Mixed together  30% of J/  s affected in static B=10 15 T 142ns 10ns   0.12ns  P. Filip @ CPOD 2013

21. Positronium e e (1S, 2S...) ortho-ee ( J=1, m =1,0,-1 ) and para-ee (J=0) ortho-cc (J/  m =1,0,-1 ) and para-cc (  ) Quarkonium and Positronium J/ ,  (9460),  (1020): zero magnetic moments  +  z lifetime: 142ns (3  )0.12ns (2  )  Bound state cc, bb (1S, 2S) z c  c  = 2100 fm (3  )c  = 6.9 fm (2  ) color hyperfine   E =117 MeV MAGNETIC QUENCHING OF ortho-Positronium DECAY J/  P. Filip @ CPOD 2013