Optoelectronic electronic skins, or e-skins, introduce electronic sensing and displays on the surface of human skin.

We study the properties of the strongly-coupled quark-gluon plasma with a multistage model of heavy ion collisions that combines the TRENTo initial condition ansatz, free-streaming, viscous relativistic hydrodynamics, and a relativistic hadronic transport. A model-to-data comparison with Bayesian inference is performed, revisiting assumptions made in previous studies. The role of parameter priors is studied in light of their importance towards the interpretation of results. We emphasize the use of closure tests to perform extensive validation of the analysis workflow before comparison with observations. Our study combines measurements from the Large Hadron Collider and the Relativistic Heavy Ion Collider, achieving a good simultaneous description of a wide range of hadronic observables from both colliders. The selected experimental data provide reasonable constraints on the shear and the bulk viscosities of the quark-gluon plasma at T ∼ 150-250 MeV, but their constraining power degrades at higher temperatures T 250 MeV. Furthermore, these viscosity constraints are found to depend significantly on how viscous corrections are handled in the transition from hydrodynamics to the hadronic transport. Several other model parameters, including the free-streaming time, show similar model sensitivity, while the initial condition parameters associated with the TRENTo ansatz are quite robust against variations of the particlization prescription. We also report on the sensitivity of individual observables to the various model parameters. Finally, Bayesian model selection is used to quantitatively compare the agreement with measurements for different sets of model assumptions, including different particlization models and different choices for which parameters are allowed to vary between RHIC and LHC energies. CONTENTS Pratt-Torrieri-Bernhard 10 D. Hadronic transport 11 IV. Specifying prior knowledge 11 V. Bayesian Parameter Estimation with a Statistical Emulator 13 A. Overview of Bayesian Parameter Estimation 13 B. Physical model emulator 14 C. Treatment of uncertainties 16 D. Sampling of the posterior 17 E. Maximizing the posterior 17 VI. Closure Tests 17 A. Validating Bayesian inference with closure tests 18 B. Guiding analyses with closure tests 18 37 A. Full posterior of model parameters 37 B. Posterior for LHC and RHIC independently 37 C. Validation of principal component analysis 37 D. Experimental covariance matrix 38 E. Reducing experimental uncertainty 39 F. Bulk relaxation time 39 G. Comparison to previous studies 40 1. Physics models 41 2. Prior distributions 42 3. Experimental data 42 H. Multistage model validation 42 1. Validation of second-order viscous hydrodynamics implementation 42 a. Validation against cylindrically symmetric external solution 43 2. SMASH 43 3. Comparison of JETSCAPE with hic-eventgen 45 4. The σ meson 46 5. Sampling particles on mass-shell 47 6. QCD equations of state with different hadron resonance gases 47 References 48

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We study the nuclear modifications of full jets and their structures in relativistic heavy-ion collisions including the effect of hydrodynamic medium response to jet quenching. To study the evolutions of the full jet shower and the traversed medium with energy and momentum exchanges between them, we formulate a coupled jet-fluid model consisting of a set of jet transport equations and relativistic hydrodynamics equations with source terms. In our model, the full jet shower interacts with the medium and gets modified via collisional and radiative processes during the propagation. Meanwhile, the energy and momentum are deposited from the jet shower to the medium and then evolve with the medium hydrodynamically. The full jet defined by a cone size in the final state includes the jet shower and the particles produced from jet-induced flow. We apply our model to calculate the full jet energy loss and the nuclear modifications of jet rate and shape in Pb+Pb collisions at $2.76{\rm A~TeV}$. It is found that the inclusion of jet-induced flow contribution leads to stronger jet-cone size dependence for jet energy loss and jet suppression. Jet-induced flow also has a significant contribution to jet shape function and dominates at large angles away from the jet axis.Comment: 13 pages, 6 figure

We study the transport dynamics of momenta deposited from jets in ultrarelativistic heavyion collisions. Assuming that the high-energy partons traverse expanding quark-gluon fluids and are subject to lose their energy and momentum, we simulate dijet asymmetric events by solving relativistic hydrodynamic equations numerically without linearization in the fully (3+1)-dimensional coordinate. Mach cones are formed and strongly broadened by radial flow of the background medium. As a result, the yield of low-pT particles increases at large angles from the jet axis and compensates the dijet momentum imbalance inside the jet-cone. This provides an intimate link between the medium excitation by jets and results in dijet asymmetric events observed by the CMS Collaboration. Introduction.-The quark gluon plasma (QGP), supposed to have filled the early universe a few microseconds after the Big Bang, is the deconfined state of quarks and gluons realized under an extremely hot and dense condition [1]. In heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) at BNL and the Large Hadron Collider (LHC) at CERN, the QGP is created experimentally. By colliding relativistically accelerated heavy nuclei, extremely high-temperature is achieved in the experiments. From the analysis of experimental data of elliptic flow, it has turned out that the QGP behaves like an almost-perfect fluid because of the strong interacton among the constituent particles [2-6].Jets, namely partons with large transverse momenta, are created in hadron or nuclear collisions at collider energies. In nuclear collisions, these partons are subject to traverse a hot and dense medium. While traversing the medium, the parton loses its energy through strong interaction between them [7][8][9][10][11][12][13]. Through the amount of lost energy, one can extract one of the fundamental properties of the medium, namely stopping power of the QGP against high-energy partons. In addition, the energymomentum deposition from jets excites the medium and propagation of this medium excitation may give information about the transport coefficients and the sound velocity of the QGP. Thus jet quenching phenomena provide a unique opportunity to probe the properties of the primordial matter composed of elementary particles in quantum chromodynamics (QCD).The next question is where and how this lost energy diffuses inside the medium. In experiments, a large number of low-p T hadrons at large angles from an axis of the quenched jet is observed in Pb-Pb collisions at the LHC [14]. The total transverse momentum of these low-p T particles together with the quenched jet balances that of

We propose a new approach to initialize the hydrodynamic fields such as energy density distributions and four flow velocity fields in hydrodynamic modeling of high-energy nuclear collisions at the collider energies. Instead of matching the energy-momentum tensor or putting the initial conditions of quark-gluon fluids at a fixed initial time, we utilize a framework of relativistic hydrodynamic equations with source terms to describe the initial stage. Putting the energy and momentum loss rate of the initial partons into the source terms, we obtain hydrodynamic initial conditions dynamically. The resultant initial profile of the quark-gluon fluid looks highly bumpy as seen in the conventional event-by-event initial conditions. In addition, initial random flow velocity fields also are generated as a consequence of momentum deposition from the initial partons. We regard the partons that survive after the dynamical initialization process as the mini-jets and find sizable effects of both mini-jet propagation in the quark-gluon fluids and initial random transverse flow on the final momentum spectra and anisotropic flow observables. We perform event-by-event (3 + 1)-dimensional ideal hydrodynamic simulations with this new framework that enables us to describe the hydrodynamic bulk collectivity, parton energy loss, and interplay among them in a unified manner.

We develop the dynamical core-corona initialization framework as a phenomenological description of the quark gluon plasma (QGP) fluids formation in high-energy nuclear collisions. Using this framework, we investigate the fraction of the fluidized energy to the total energy and strange hadron yield ratios as functions of multiplicity and scrutinize the multiplicity scaling of hadron yield ratios recently reported by ALICE Collaboration. Our results strongly indicate that the QGP fluids are partly formed even at the averaged multiplicity for non-single diffractive p+p events.

Organic electronic devices implemented on flexible thin films are attracting increased attention for biomedical applications because they possess extraordinary conformity to curved surfaces. A neuronal device equipped with an organic light-emitting diode (OLED), used in combination with animals that are genetically engineered to include a light-gated ion channel, would enable cell type-specific stimulation to neurons as well as conformal contact to brain tissue and peripheral soft tissue. This potential application of the OLEDs requires strong luminescence, well over the neuronal excitation threshold in addition to flexibility. Compatibility with neuroimaging techniques such as MRI provides a method to investigate the evoked activities in the whole brain. Here, we developed an ultrathin, flexible, MRI-compatible OLED device and demonstrated the activation of channelrhodopsin-2–expressing neurons in animals. Optical stimulation from the OLED attached to nerve fibers induced contractions in the innervated muscles. Mechanical damage to the tissues was significantly reduced because of the flexibility. Owing to the MRI compatibility, neuronal activities induced by direct optical stimulation of the brain were visualized using MRI. The OLED provides an optical interface for modulating the activity of soft neuronal tissues.