Angular distribution of thrust axis with power-suppressed contribution in e+e- annihilation

Structure function of e+e- to hadrons cross section proportional to the longitudinal part of the hadron tensor is power suppressed with respect to an event shape variable in the two-jet region. In the SCET framework, we study the event shape distribution for this structure function to NLL level of accuracy. As, a result we obtain the angular distribution of hadron jets as a function of the thrust, in the two jet region. We further examine effects of non-perturbative hadronization corrections by adopting a shape function that reproduce the observed event shape distributions. Impacts of our findings on the electroweak measurements via the jet angular forward-backward asymmetry are discussed.Comment: 28 pages, 9 figure

Smooth plug-in inverse estimators in the current status continuous mark model

We consider the problem of estimating the joint distribution function of the event time and a continuous mark variable when the event time is subject to interval censoring case 1 and the continuous mark variable is only observed in case the event occurred before the time of inspection. The nonparametric maximum likelihood estimator in this model is known to be inconsistent. We study two alternative smooth estimators, based on the explicit (inverse) expression of the distribution function of interest in terms of the density of the observable vector. We derive the pointwise asymptotic distribution of both estimators.Comment: 29 pages, 12 figure

A Study of the Di-Hadron Angular Correlation Function in Event by Event Ideal Hydrodynamics

The di-hadron angular correlation function is computed within boost invariant, ideal hydrodynamics for Au+Au collisions at $\sqrt{s}_{NN}=200$ GeV using Monte Carlo Glauber fluctuating initial conditions. When $0<p_T< 3$ GeV, the intensity of the flow components and their phases, $\left\{v_n, \Psi_n \right \}$ ($n=2,3$), are found to be correlated on an event by event basis to the initial condition geometrical parameters $\left\{\varepsilon_{2,n}, \Phi_{2,n} \right \}$, respectively. Moreover, the fluctuation of the relative phase between trigger and associated particles, $\Delta_n =\Psi_n^t - \Psi_n^a$, is found to affect the di-hadron angular correlation function when different intervals of transverse momentum are used to define the trigger and the associated hadrons.Comment: 15 pages, 10 figures; typos fixed, added reference

The Narrowing of Charge Balance Function and Hadronization Time in Relativistic Heavy Ion Collisions

The widths of charge balance function in high energy hadron-hadron and relativistic heavy ion collisions are studied using the Monte Carlo generators PYTHIA and AMPT, respectively. The narrowing of balance function as the increase of multiplicity is found in both cases. The mean parton-freeze-out time of a heavy-ion-collision event is used as the characteristic hadronization time of the event. It turns out that for a fixed multiplicity interval the width of balance function is consistent with being independent of hadronization time.Comment: 4 pages, 7 figure

Mass function and particle creation in Schwarzschild-de Sitter spacetime

We construct a mass or energy function for the non-Nariai class Schwarzschild-de Sitter black hole spacetime in the region between the black hole and the cosmological event horizons. The mass function is local, positive definite, continuous and increases monotonically with the radial distance from the black hole event horizon. We derive the Smarr formula using this mass function, and demonstrate that the mass function reproduces the two-temperature Schwarzschild-de Sitter black hole thermodynamics, along with a term corresponding to the negative pressure due to positive cosmological constant. We further give a field theoretic derivation of the particle creation by both the horizons and discuss its connection with the mass function.Comment: v3, 16pp; added references and discussions, typo corrected; accepted in Eur. Phys. J.

Multiple-event probability in general-relativistic quantum mechanics

We discuss the definition of quantum probability in the context of "timeless" general--relativistic quantum mechanics. In particular, we study the probability of sequences of events, or multi-event probability. In conventional quantum mechanics this can be obtained by means of the ``wave function collapse" algorithm. We first point out certain difficulties of some natural definitions of multi-event probability, including the conditional probability widely considered in the literature. We then observe that multi-event probability can be reduced to single-event probability, by taking into account the quantum nature of the measuring apparatus. In fact, by exploiting the von-Neumann freedom of moving the quantum classical boundary, one can always trade a sequence of non-commuting quantum measurements at different times, with an ensemble of simultaneous commuting measurements on the joint system+apparatus system. This observation permits a formulation of quantum theory based only on single-event probability, where the results of the "wave function collapse" algorithm can nevertheless be recovered. The discussion bears also on the nature of the quantum collapse

Does Time Really Slow Down during a Frightening Event?

Observers commonly report that time seems to have moved in slow motion during a life-threatening event. It is unknown whether this is a function of increased time resolution during the event, or instead an illusion of remembering an emotionally salient event. Using a hand-held device to measure speed of visual perception, participants experienced free fall for 31 m before landing safely in a net. We found no evidence of increased temporal resolution, in apparent conflict with the fact that participants retrospectively estimated their own fall to last 36% longer than others' falls. The duration dilation during a frightening event, and the lack of concomitant increase in temporal resolution, indicate that subjective time is not a single entity that speeds or slows, but instead is composed of separable subcomponents. Our findings suggest that time-slowing is a function of recollection, not perception: 1a richer encoding of memory may cause a salient event to appear, retrospectively, as though it lasted longer