Low mass dilepton production in relativistic heavy ion collisions

Lapidus, K.; Emelyanov, V. M.

doi:10.1134/s106377960901002x

Cited by 18 publications

(31 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In the second case there are some experimental indications of an abnormal dilepton excess in the range of low invariant masses and rapidities and moderate values of the transverse momenta [7]- [11] (see the reviews in [12]), which can be thought of as a result of LPB in the medium (the details can be found in [13]). In particular, in heavy-ion collisions at high energies, with raising temperatures and baryon densities, metastable states can appear in the finite-volume fireball with a nontrivial topological axial charge (due to fluctuations of gluonic fields) T 5 , which is related to the gluon gauge field G i ,…”

Section: Topological Charge Chiral Imbalance and Axial Chemical Potementioning

confidence: 99%

Exotic meson decays in the environment with chiral imbalance

Andrianov

Espriu

et al. 2017

EPJ Web Conf.

View full text Add to dashboard Cite

Abstract. An emergence of Local Parity Breaking (LPB) in central heavy-ion collisions (HIC) at high energies is discussed. LPB in the fireball can be produced by a difference between the number densities of right-and left-handed chiral fermions (Chiral Imbalance) which is implemented by a chiral (axial) chemical potential. The effective meson lagrangian induced by QCD is extended to the medium with Chiral Imbalance and the properties of light scalar and pseudoscalar mesons (π, a 0 ) are analyzed. It is shown that exotic decays of scalar mesons arise as a result of mixing of π and a 0 vacuum states in the presence of chiral imbalance. The pion electromagnetic formfactor obtains an unusual parity-odd supplement which generates a photon polarization asymmetry in pion polarizability. We hope that the above pointed indications of LPB can be identified in experiments on LHC, RHIC, CBM FAIR and NICA accelerators. Topological charge, Chiral Imbalance and axial chemical potentialThe behaviour of baryonic matter under extreme conditions has got recently a lot of interest [1,2]. A medium generated in the heavy ion collisions may serve for detailed studies, both experimental and theoretical, of various phases of hadron matter. In this context new properties of QCD in the hot and dense environment are tested in current accelerator experiments on RHIC and LHC [3,4].In heavy ion collisions, in principle, there are two distinct experimental situations for peripheral and central collisions. In the first case the so-called Chiral Magnetic Effect (CME) can be detected, details see in [5] and also [6] for a review and additional references.In the second case there are some experimental indications of an abnormal dilepton excess in the range of low invariant masses and rapidities and moderate values of the transverse momenta [7]-[11] (see the reviews in [12]), which can be thought of as a result of LPB in the medium (the details can be found in [13]). In particular, in heavy-ion collisions at high energies, with raising temperatures and baryon densities, metastable states can appear in the finite-volume fireball with a nontrivial topological ⋆

show abstract

Section: Topological Charge Chiral Imbalance and Axial Chemical Potementioning

confidence: 99%

Exotic meson decays in the environment with chiral imbalance

Andrianov

Espriu

et al. 2017

EPJ Web Conf.

View full text Add to dashboard Cite

show abstract

“…From comparison to proton-proton and proton-nucleus collisions it has been well established that such an enhancement is undoubtedly a nuclear medium effect [9]. For the energies accessible at GSI (of few GeV per nucleon in HADES experiments [8]) with light nuclei the above effect was partially interpreted as being due to enhanced η meson production in proton-neutron scattering [11].…”

Section: Pos(qfthep2010)053mentioning

confidence: 99%

“…For the energies accessible at GSI (of few GeV per nucleon in HADES experiments [8]) with light nuclei the above effect was partially interpreted as being due to enhanced η meson production in proton-neutron scattering [11]. For the higher energies accessible at CERN SPS and BNL RHIC of order of 100 GeV per nucleon, in CERES, HELIOS/3, NA60 [5] and, especially, in PHENIX [7] (see, Fig.3) experiments, the abnormal dilepton yield has not been yet explained at full extent by any mechanisms known in hadron phenomenology [9,10].…”

Section: Pos(qfthep2010)053mentioning

confidence: 99%

See 1 more Smart Citation

The problem of anomalous dilepton yield in relativistic heavy-ion collisions

Andrianov¹,

Andrianov²,

Espriu³

et al. 2011

Proceedings of the XIXth International Workshop on High Energy Physics and Quantum Field Theory — PoS(QFTHEP2010)

View full text Add to dashboard Cite

The recent data on abnormal excess of dileptons in central heavy ion collisions are surveyed. We propose a novel explanation for this dilepton excess observed in dense/hot nuclear matter at invariant masses below 1 GeV. We argue that the presence of local parity breaking (LPB) due to a slowly varying time-dependent isosinglet and/or isotriplet pseudoscalar condensate may substantially modify the dispersion relation of photons and vector mesons propagating in such a medium, resulting in a large excess of l + l − with respect to the common theoretical predictions. Various experimental options to prove or falsify this effect are discussed.

show abstract

“…Another interesting area for observation of parity breaking is the heavy ion physics. Recently several experiments in heavy ion collisions have indicated an abnormal yield of lepton pairs of invariant mass < 1 GeV in the region of small rapidities and moderate transversal momenta [55,56,57,58,59] (see, the reviews [60,61]). This phenomenon is stronger for central collisions with moderate transversal momenta of dileptons.…”

Section: Introduction: Possible Physics Of Time-or Space-dependent Psmentioning

confidence: 99%

Propagation of photons and massive vector mesons between a parity breaking medium and vacuum

Andrianov

Kolevatov

Soldati

2011

J. High Energ. Phys.

View full text Add to dashboard Cite

Abstract:The problem of propagation of photons and massive vector mesons in the presence of Lorenz and CPT invariance violating medium is studied when the parity-odd medium is bounded by a hyperplane separating it from the vacuum. The solutions in both half-spaces are carefully discussed and in the case of space-like boundary stitched on the boundary with help of the Bogolubov transformations provided by the space-like ChernSimons vector. The presence of two different Fock vacua is shown and the probability amplitude for transmission of particles from vacuum to parity breaking medium is calculated. We have also found classical solutions and showed that the results are consistent with ones obtained by canonical quantization formalism. In the cases, both of entrance to and of escaping from parity-odd medium, the probabilities for reflecting and passing through were found for each polarization using the classical solutions. Finally, the propagator for each polarization is obtained in the momentum space. Boundary effects under consideration are of certain importance for registration of local parity violation in the finite volume of heavy ion fireball and/or of a star with cold axion condensate.

show abstract

Low mass dilepton production in relativistic heavy ion collisions

Cited by 18 publications

References 50 publications

Exotic meson decays in the environment with chiral imbalance

Exotic meson decays in the environment with chiral imbalance

The problem of anomalous dilepton yield in relativistic heavy-ion collisions

Propagation of photons and massive vector mesons between a parity breaking medium and vacuum

Contact Info

Product

Resources

About