Dynamics of Hot QCD Matter -- Current Status and Developments

The discovery and characterization of hot and dense QCD matter, known as Quark Gluon Plasma (QGP), remains the most international collaborative effort and synergy between theorists and experimentalists in modern nuclear physics to date. The experimentalists around the world not only collect an unprecedented amount of data in heavy-ion collisions, at Relativistic Heavy Ion Collider (RHIC), at Brookhaven National Laboratory (BNL) in New York, USA, and the Large Hadron Collider (LHC), at CERN in Geneva, Switzerland but also analyze these data to unravel the mystery of this new phase of matter that filled a few microseconds old universe, just after the Big Bang. In the meantime, advancements in theoretical works and computing capability extend our wisdom about the hot-dense QCD matter and its dynamics through mathematical equations. The exchange of ideas between experimentalists and theoreticians is crucial for the progress of our knowledge. The motivation of this first conference named "HOT QCD Matter 2022" is to bring the community together to have a discourse on this topic. In this article, there are 36 sections discussing various topics in the field of relativistic heavy-ion collisions and related phenomena that cover a snapshot of the current experimental observations and theoretical progress. This article begins with the theoretical overview of relativistic spin-hydrodynamics in the presence of the external magnetic field, followed by the Lattice QCD results on heavy quarks in QGP, and finally, it ends with an overview of experiment results.Comment: Compilation of the contributions (148 pages) as presented in the `Hot QCD Matter 2022 conference', held from May 12 to 14, 2022, jointly organized by IIT Goa & Goa University, Goa, Indi

Determination of interfacial dielectric constant of AOT-based reverse micelle by probing magnetic field effect on pyrene-DMA exciplex luminescence

The effect of magnetic field on the luminescence of pyrene-DMA exciplex confined within the reverse micellar (RM) environment of various cavity sizes is reported. The field-modulated change in luminescence Δφ/φ) at various w values is strikingly similar to the Δφ/φ vs dielectric constant (ε) variation of solvent mixtures which suggests that e of the RM interface is primarily responsible for the variation of magnetic field effect (MFE). The interfacial dielectric constant at different w values may be evaluated on the basis of the above similarity

Magnetic field effect on exciplex luminescence: a study of multiple exciplex formation dynamics in biomimicking environment

The interfacial environment of AOT based reverse micelle (RM), which has similarity with bio-membranes, has been probed by measuring: (1) magnetic field effect (MFE) on Pyrene-DMA exciplex luminescence; (2) wavelength-dependence of the exciplex lifetime. At least two different types of exciplexes have been identified at different locations within the RM interface. Among these, only the red edge component of the emission centered at ~500 nm (Ex<SUB>500</SUB>) is field-sensitive. It makes sense to presume that the Ex<SUB>500</SUB> is localized at the mobile zone of the interface while the other field-insensitive one, centered at ~430 nm (Ex<SUB>430</SUB>) resides at the immobile zone of the interface. Time resolutions of luminescence at different wavelengths indicate that the field-sensitive exciplex is formed at the expense of Ex<SUB>430</SUB>

Magnetic field effect on pyrene-DMA exciplex luminescence in non-aqueous AOT reverse micelle

Magnetic field effect (MFE) on pyrene-DMA exciplex luminescence and exciplex lifetime have been studied in reverse micelle of Aerosol-OT in n-heptane in presence of N,N-dimethylformamide and methanol as the polar solvent at different Ws (Ws = [polar solvent]/[surfactant]) values. It is found that two types of exciplexes are residing at different locations of the non-aqueous reverse micelle. Out of these only the exciplex emitting at longer wavelength is found to be field sensitive. The higher MFE and shorter lifetime of the exciplex in non-aqueous reverse micelle compared to that of aqueous micelle have been explained on the basis of presence of hydrogen bonding and dipolar interaction between the solvent and the polar head group of the micelle

Influence of molecular shape on magnetic field effect on photo-induced geminate radical pair in SDS micellar medium

The magnetic field effects (MFEs) on the dynamics of the two radical pairs (RPs), one generated by photo-excitation of phenyl pyrilium ion (PP+) in the presence of SDS micelles and an electron donor, biphenyl, and the other similarly generated from a SDS micellar solution of biphenyl and trioxotriangulenium carbocation (OXO+), have been compared. At zero field, the RP (PP·/BP·+) has much higher recombination rate, but much lower escape rate in comparison to the RP (OXO· /BP·+). The field-dependent yields and lifetimes show saturation early ( &lt;0.1 T) in case of the latter, but in case of the former, the saturation does not occur, not even at a field of 5 T. The results have been interpreted in terms of relaxation mechanism (RM) for MFE and expected differences in the location of the guest in the micellar host, which affects the ratio of the rate of recombination to the rate of escape

Magnetic field control of the back-electron-transfer process following photoinduced electron transfer (piet) in biphenyl/phenylpyrylium salts in SDS micellar medium

Magnetic field effect (MFE) on the radical pairs (RPs) generated by the photoexcitation of the phenyl pyrylium ion (PP+) in the presence of the electron donor biphenyl has been investigated. A large effect was observed particularly for the BP/PP+ (I) case; the escape yield at 5 T was more than 20 times the zero-field value at a long time delay. The low-field variation of MFE conforms to the pattern expected for the isotropic HFC (hyperfine coupling) mechanism, and the high-field variation conforms to that expected for the relaxation mechanism. The addition of salt causes saturation at a slightly lower field, presumably because of a change in the rotational correlation time (local motion) of PP&#183; at the micellar surface. Introduction of a methyl group in the acceptor reduces the MFE considerably the reason for which is not immediately clear

Large magnetic field effect on back electron transfer from uncharged radical to its cationic partner in anionic micelle

The magnetic field effect (MFE) on the radical pair (RP) generated by photoexcitation of the acetyl derivative of phenyl pyrylium ion (APP<SUP>+</SUP>) in the presence of biphenyl, an electron donor, has been investigated. The escape yield at 3.5 T is more than ten times the zero-field value. The MFE reaches near-saturation twice, once at fields of the order of 10mT and again at about 3.5 T. The low-field variation of the MFE conforms to the pattern expected for the isotropic HFC mechanism, and the high-field variation to that expected for the relaxation mechanism. In this particular system two types of radical pair are generated, one by electron transfer from the donor to the acceptor and another by H-abstraction from the micelle. The MFEs on the two types of <SUP>3</SUP>RP have been compared