The logarithmic contribution to the QCD static energy at NNNNLO

Using pNRQCD and known results for the field strength correlator, we calculate the ultrasoft contribution to the QCD static energy of a quark-antiquark pair at short distances at NNNNLO in alpha_s. At the same order, this provides the logarithmic terms of the singlet static potential in pNRQCD and the log alpha_s terms of the static energy.Comment: 16 pages, 5 figures. Minor modifications. References added. Journal versio

Overview of charmonium decays and production from Non-Relativistic QCD

I briefly review Non-Relativistic QCD and related effective theories, and discuss applications to heavy quarkonium decay, and production in electron-positron colliders.Comment: 8 pages, Invited talk at Charm 2010, Oct. 21-24, IHEP, Beijin

The QCD static energy at NNNLL

We compute the static energy of QCD at short distances at next-to-next-to-next-to leading-logarithmic accuracy in terms of the three-loop singlet potential. By comparing our results with lattice data we extract the value of the unknown piece of the three-loop singlet potential.Comment: 25 pages, 16 figures. v2: Incorrect files for figure 7 replaced by the correct ones. One reference adde

Extraction of alpha_s from radiative Upsilon(1S) decays

We improve on a recent determination of alpha_s from Gamma(Upsilon(1S)-->X gamma)/Gamma(Upsilon(1S)-->X) with CLEO data by taking into account color octet contributions and avoiding any model dependence in the extraction. We obtain alpha_s(M_Upsilon(1S))= 0.184+0.015-0.014, which corresponds to alpha_s(M_Z)=0.119+0.006-0.005.Comment: 11 pages. v2: One reference added. v3: Minor modification in an error estimate. Journal versio

How to compute the thermal quarkonium spectral function from first principles?

In the limit of a high temperature T and a large quark-mass M, implying a small gauge coupling g, the heavy quark contribution to the spectral function of the electromagnetic current can be computed systematically in the weak-coupling expansion. We argue that the scale hierarchy relevant for addressing the disappearance ("melting") of the resonance peak from the spectral function reads M >> T > g^2 M > gT >> g^4 M, and review how the heavy scales can be integrated out one-by-one, to construct a set of effective field theories describing the low-energy dynamics. The parametric behaviour of the melting temperature in the weak-coupling limit is specified.Comment: 8 pages; to appear in the Proceedings of SEWM08, Amsterdam, the Netherlands, August 26-29, 200

A first estimate of triply heavy baryon masses from the pNRQCD perturbative static potential

Within pNRQCD we compute the masses of spin-averaged triply heavy baryons using the now-available NNLO pNRQCD potentials and three-body variational approach. We focus in particular on the role of the purely three-body interaction in perturbation theory. This we find to be reasonably small and of the order 25 MeV Our prediction for the Omega_ccc baryon mass is 4900(250) in keeping with other approaches. We propose to search for this hitherto unobserved state at B factories by examining the end point of the recoil spectrum against triple charm.Comment: 18 figures, 21 page

Spectroscopy, leptonic decays and the nature of heavy quarkonia

We examine the electronic width ratios of Upsilon resonances below the BBbar threshold by means of an effective (Cornell-type) QCD potential incorporating 1/m_b corrections obtained from a prior fit to the bottomonium spectrum. From our analysis we conclude that the Upsilon(2S) and Upsilon(3S) states should belong to the strong-coupling (nonperturbative) regime while the Upsilon(1S) state should belong to the weak-coupling (perturbative) regime, in agreement with a previous study based on radiative decays.Comment: 8 page

Systematic study of the PDC speckle structure for quantum imaging applications

Sub shot noise imaging of weak object by exploiting Parametric Down Converted light represents a very interesting technological development. A precise characterization of PDC speckle structure in dependence of pump beam parameters is a fundamental tool for this application. In this paper we present a first set of data addressed to this purpose

EXP-Crowd: A Gamified Crowdsourcing Framework for Explainability

The spread of AI and black-box machine learning models made it necessary to explain their behavior. Consequently, the research field of Explainable AI was born. The main objective of an Explainable AI system is to be understood by a human as the final beneficiary of the model. In our research, we frame the explainability problem from the crowds point of view and engage both users and AI researchers through a gamified crowdsourcing framework. We research whether it's possible to improve the crowds understanding of black-box models and the quality of the crowdsourced content by engaging users in a set of gamified activities through a gamified crowdsourcing framework named EXP-Crowd. While users engage in such activities, AI researchers organize and share AI- and explainability-related knowledge to educate users. We present the preliminary design of a game with a purpose (G.W.A.P.) to collect features describing real-world entities which can be used for explainability purposes. Future works will concretise and improve the current design of the framework to cover specific explainability-related needs