Novel approach to measure the leptonic eta(')->mu+mu- decays via charmed meson decays

In this article, we propose a novel approach to measure the branching ratios of the leptonic eta(')-> mu+mu- decays by using charmed meson decays, namely, D+(s)->pi+ eta(')(->mu+mu-) and D0->K-pi+eta(')(->mu+mu-). We advocate that the data available at LHCb can already yield a new measurement of Br(eta->mu+mu-) with accuracy competitive with the current world average. We also estimate that using the data collected by LHCb between 2015 and 2018 in proton-proton collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.0/fb, the relative uncertainties to this branching ratio can be reduced down to ~10%. We also show that the first observation of Br(eta'->mu+mu-) may be possible with the Upgrade of the LHCb experiment.Comment: 12 pages, 3 figure

The Iran nuclear deal: the Iranian and US domestic factors that put its implementation at risk. Egmont Security Policy Brief No. 74 June 2016

The Iran nuclear deal with E3+3 and P5+1 is not without its detractors. The Iranian Conservative Party, the US Republican Party and Israel disapprove. This policy brief aims to understand the Iranian and US domestic factors that could challenge the implementation of the deal. The 15-year implementation process is likely to be affected by the state-centric Constitution of Iran, which leaves no room for foreign and, in particular, Western considerations, and by US Republican fears relating to the security of the state of Israel. Other objections come from Arab Sunni States as well as US Democrats also concerned about Israeli security

Zolotarev Quadrature Rules and Load Balancing for the FEAST Eigensolver

The FEAST method for solving large sparse eigenproblems is equivalent to subspace iteration with an approximate spectral projector and implicit orthogonalization. This relation allows to characterize the convergence of this method in terms of the error of a certain rational approximant to an indicator function. We propose improved rational approximants leading to FEAST variants with faster convergence, in particular, when using rational approximants based on the work of Zolotarev. Numerical experiments demonstrate the possible computational savings especially for pencils whose eigenvalues are not well separated and when the dimension of the search space is only slightly larger than the number of wanted eigenvalues. The new approach improves both convergence robustness and load balancing when FEAST runs on multiple search intervals in parallel.Comment: 22 pages, 8 figure

Un site géologique remarquable à protéger et à valoriser : le Veillon à Talmont-Saint-Hilaire (Vendée, France)

It has been forty years since the Jurassic site of Veillon in Talmont-Saint-Hilaire (Vendée, France), where footprints of vertebrates were found, was plundered. This outstanding site belonging to Vendée's geological patrimony needs to be preserved and developed. Some footprints from Veillon are displayed in the collections of about thirty public institutions and six museums

‘Pushing Through’ in Plato’s Sophist: A New Reading of the Parity Assumption

At a crucial juncture in Plato’s Sophist, when the interlocutors have reached their deepest confusion about being and not-being, the Eleatic Visitor proclaims that there is yet hope. Insofar as they clarify one, he maintains, they will equally clarify the other. But what justifies the Visitor’s seemingly oracular prediction? A new interpretation explains how the Visitor’s hope is in fact warranted by the peculiar aporia they find themselves in. The passage describes a broader pattern of ‘exploring both sides’ that lends insight into Plato’s aporetic method

EU Diplomacy and the Iran Nuclear Deal: Staying power? CEPS Policy Insights No 2017-28 / 14 July 2017

The nuclear deal with Iran is often hailed as one of the few diplomatic successes of EU foreign policy. While the convening power of the European Union in ‘the making of’ phase of the Joint Comprehensive Plan of Action (JCPOA) has indeed been critical and well documented, there has so far been no independent assessment of the EU’s facilitating and mediating role in the implementation of the nuclear agreement

Des éléphants antiques (Palaeoloxodon antiquus) à Brétignolles-sur-Mer (Vendée, France)

Following the 1989-90 winter storms, remains of several straight-tusked elephants as well as a rich quaternary paleoflora were found on the strand of La Parée beach in Brétignolles-sur-Mer (Vendée, France). The story of these findings, the diggings of the bones, the dating and the paleoenvironment of the deposits are mentioned in this article. The sediments are old "peat bogs" which belong to two distinct eras : Pleistocene (peat bog holding the remains of straight-tusked elephants) and Holocene (peat bog showing tracks of Bovidae and prints of tools, and higher peat bogs)

Reweighting of the form factors in exclusive B --> X ell nu decays

A form factor reweighting technique has been elaborated to permit relatively easy comparisons between different form factor models applied to exclusive B --> X l nu decays. The software tool developped for this purpose is described. It can be used with any event generator, three of which were used in this work: ISGW2, PHSP and FLATQ2, a new powerful generator. The software tool allows an easy and reliable implementation of any form factor model. The tool has been fully validated with the ISGW2 form factor hypothesis. The results of our present studies indicate that the combined use of the FLATQ2 generator and the form factor reweighting tool should play a very important role in future exclusive |Vub| measurements, with largely reduced errors.Comment: accepted for publication by EPJ

Towards a direct route to turbulence in an open rotating cavity

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