Elena Dundovich, Francesca Gori, Emanuela Guercetti, eds., Reflections on the Gulag

Fruit d’une longue collaboration entre la Fondation Feltrinelli et l’Association Memorial, cet ouvrage aux multiples entrées (bibliographie, articles de synthèse, articles spécialisés, recueils de documents) est à la fois un formidable instrument de travail et un état précis des lieux de la recherche sur le Goulag. Il permet de mesurer l’immense progrès accompli depuis une dizaine d’années dans la connaissance des divers cercles du système répressif stalinien, longtemps fondée sur les seuls t..

Valters Nollendorfs, Erwin Oberländer, eds., The Hidden and Forbidden History of Latvia under Soviet and Nazi Occupations

Ce volume d’articles, publié sous l’égide de la Commission internationale d’historiens mise en place par le gouvernement de la République de Lettonie en 1998, aborde tout un ensemble de questions « sensibles » relatives aux deux grandes occupations, nazie et soviétique, qui ont marqué l’histoire de ce pays balte au xxe siècle. Quatorzième de la série, ce volume s’inscrit dans un ensemble déjà fort conséquent de publications encore malheureusement largement méconnues en Occident et notamment e..

Jean-Paul Depretto, Pouvoirs et société en Union Soviétique

Comme la plupart des recueils d’articles écrits par des auteurs divers et rassemblés a posteriori, celui qu’a constitué Jean-Paul Depretto ne présente pas, de prime abord, une grande homogénéité. Ce défaut, inhérent au genre, ne nuit en rien à la qualité de l’ensemble, la plupart des articles apportant, chacun sur un champ d’étude précis, une analyse pertinente. Dans la continuité de sa contribution sur la violence (Le siècle des communismes), Peter Holquist met l’accent sur le rôle crucial d..

L’OGPU en 1924

RésuméÀ partir de rapports internes présentés par les différents services de l’OGPU à Feliks Dzeržinskij à la fin de 1924, cet article analyse la structure de l’OGPU à un moment peu connu de l’histoire de la police politique. Durant le bref apogée de la NEP, la place et le rôle de la police politique dans le système soviétique font l’objet de vifs débats. Un certain nombre d’institutions (justice, finances, affaires étrangères) souhaitent limiter les moyens de l’OGPU. Quant aux tchékistes, ils font valoir la forte diminution, depuis 1921, de leurs moyens, et l’immensité des tâches auxquelles ils sont confrontés dans un environnement interne et externe hostile. Les rapports de l’OGPU présentés à l’occasion de la discussion du budget de la police politique fournissent un état détaillé des structures et des activités d’une institution sur la défensive, profondément frustrée par la situation politique du moment, incertaine de son avenir, après les années héroïques de la guerre civile et du « communisme de guerre ».AbstractThe OGPU in 1924: A close look at an institution in crisis.This article, which is based on internal reports prepared by the OGPU’s different departments for Feliks Dzerzhinskii in late 1924, focuses on the organizational structure of the OGPU at a specific and largely unknown period in the history of the Soviet political police. At the height of NEP, discussions about the status and functions of the political police in the Soviet system were raging. A number of “soft-line” administrations (justice, finance, foreign affairs) tried to cut the OGPU’s budget. Secret police officials, however, pointed at the sharp reductions that their budget had been undergoing since 1921 and stressed the immensity of their tasks in a hostile environment. OGPU reports written for the political police budget vote offer a precise and thorough picture of the organization and activities of the OGPU -- an institution deeply frustrated by the political situation of the time and uncertain about its future after the “heroic years” of the Civil War and War Communism

On the semantic representation of relative clauses in English.

Few recent studies of relativization attempt to deal with semantic distinctions between Restrictives (Rs) and Non-Restrictives (NRs), and none satisfactorily. But the distinctions are fundamental, and must be treated by rules having semantic and contextual orientation. The functions of context are examined at some length, and it is suggested that many semantic and syntactic operations usually treated separately are in fact contextually-determined - by the general semantic coherence of the discourse, and by the operation of focus within it. The deictic implications of context-related Rs of several types are distinguished from those of the context-independent function of generic. Generic Rs are taken to be the fundamental R type. Evidence is presented suggesting that Rs and NRs derive from different sources. NRs are subsequently shown not exclusively to derive from conjunction, but often to exhibit more complex semantic relationships between antecedent and relative clauses, whereas Rs and their antecedent clauses are semantically single units. This difference is explored using a generative-semantic model, and suggesting how the context ultimately specifies not only R as against NR, but also the various types of R. Interpretive semantic models, it is suggested, cannot account for these distinctions at all; neither can sentence-grammars. Conclusions - Rs subjoin relative to antecedent clause, whereas NRs conjoin them (though not only with logical 'A'); - The basic R is generic; other deictic types are regularly derived from generic contextually. Semantic theory must therefore account for context; - The relationship of full- or partial-synonymy between (all) lexical items and (some) generic Rs suggests complete or partial identity of underlying semantic structure. At present, only Generative-Semantics (modified for context- and role-specification) can handle this; - Considerable overlaps between relative clauses and focussed constructions appear to suggest that contextual focus may eventually determine all the distinctions involved

Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal

Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter