Polariton Pattern Formation and Photon Statistics of the Associated Emission

We report on the formation of a diverse family of transverse spatial polygon patterns in a microcavity polariton fluid under coherent driving by a blue-detuned pump. Patterns emerge spontaneously as a result of energy-degenerate polariton-polariton scattering from the pump state to interfering high order vortex and antivortex modes, breaking azimuthal symmetry. The interplay between a multimode parametric instability and intrinsic optical bistability leads to a sharp spike in the value of second order coherence g (2)(0) of the emitted light, which we attribute to the strongly superlinear kinetics of the underlying scattering processes driving the formation of patterns. We show numerically by means of a linear stability analysis how the growth of parametric instabilities in our system can lead to spontaneous symmetry breaking, predicting the formation and competition of different pattern states in good agreement with experimental observations

Exciton-polariton gap solitons in two-dimensional lattices

We report on the two-dimensional gap-soliton nature of exciton-polariton macroscopic coherent phases (PMCP) in a square lattice with a tunable amplitude. The resonantly excited PMCP forms close to the negative mass M point of the lattice band structure with energy within the lattice band gap and its wave function localized within a few lattice periods. The PMCPs are well described as gap solitons resulting from the interplay between repulsive polariton-polariton interactions and effective attractive forces due to the negative mass. The solitonic nature accounts for the reduction of the PMCP coherence length and optical excitation threshold with increasing lattice amplitude

Термическая гелий-кислородная смесь в лечебном алгоритме больных с COVID-19

Background. The paper discusses the use of a thermal helium-oxygen mixture (t-Не/О2 ), a novel technology, in treating patients with the 2019-nCoV acute respiratory disease (COVID-19) who develop life-threatening respiratory failure. Aim to evaluate the safety and efficacy of t-Не/О2 inhalation combined with standard therapy in the treatment of acute respiratory failure in patients with COVID-19. Materials and Methods. This was a single-center, randomized, prospective study of 70 patients with COVID-19. All patients were divided into two groups: in Group 1 (n = 38) patients received t-He/О2 in addition to the standard COVID-19 treatment; and in Group 2 (n = 32) patients were given the standard treatment in accordance with the Clinical Treatment Guidelines for patients with COVID-19, developed by the Ministry of Health of the Russian Federation. The male/female ratio was 18/20 in Group 1 and 18/14 in Group 2. The mean age of the patients in the study was 53.5 years (43; 62): 56 years (42; 64) in Group 1 and 52 years (43; 66) in Group 2. All patients had computed tomography (CT) signs of lung injury: ground-glass opacities and areas of consolidation. SARS-CoV-2 RNA was detected in 30 Group 1 patients and 28 Group 2 patients. The patients were matched by sex, age, body mass index (BMI), area of pulmonary involvement, and laboratory findings. All patients provided voluntary informed consent to participate in the study and signed a consent form. Results. Inhalation of thermal helium-oxygen mixture combined with standard therapy did not cause any procedure-related side effects in any of the patients. The following changes were observed in all patients: pO2 /FiO2 , SpO2 , and lymphocyte counts increased, C-reactive protein (CRP) levels decreased, and D-dimer and ferritin levels returned to normal. In Group 1 statistically significant changes in the above-mentioned parameters were seen within three days, while in Group 2 the same changes were observed between Days 7 and 10 of treatment. In Group 1 patients cleared SARS-CoV-2 within 4872 hours after initiation of inhalation, which was confirmed by polymerase chain reaction (PCR), and in Group 2 virus elimination was achieved within 72168 hours. Conclusion. The addition of inhalation of a thermal gas mixture of helium and oxygen (t-He/О2 ) to the standard therapy for patients with SARS-CoV-2 infection, CT signs of pneumonia (grades СT2 or CT3), and acute respiratory failure improves gas exchange, contributes to a more rapid virus elimination, and indirectly reduces inflammation.Обоснование. В представленной работе речь пойдет о новой технологии применения термического гелия и кислорода (t-Не/О2 ) в лечении больных с вирусным заболеванием СOVID-19 на этапе развития жизнеугрожающего синдрома дыхательной недостаточности. Цель изучить безопасность и эффективность ингаляционной терапии t-Не/О2 в лечении острой дыхательной недостаточности пациентов с СOVID-19 на фоне стандартной терапии. Материалы и методы. В одноцентровое рандомизированное проспективное исследование было включено 70 пациентов с COVID-19. Пациенты были разделены на две группы: в первой (n = 38) в стандартный протокол лечения COVID-19 была включена терапия t-Не/О2 ; во второй (n = 32) проводилась стандартная терапия в соответствии с клиническими рекомендациями Минздрава России для больных с COVID. В первой группе соотношение мужчины/женщины 18/20, а во второй 18/14. Средний возраст пациентов в исследовании составлял 53,5 года (43 года мужчины; 62 года женщины), в первой группе 56 лет (42 и 64 года соответственно), во второй 52 года (43 и 66 лет). У всех пациентов имелись КТ-признаки поражения легких по типу матового стекла, участки консолидации. Тест РНК коронавируса SARS-CoV-2 положительный в первой группе у 30 пациентов, во второй у 28. Пациенты сопоставимы по полу, возрасту, индексу массы тела (ИМТ), площади поражения легочной паренхимы, лабораторным данным. Всеми пациентами было подписано информированное добровольное согласие на участие в исследовании. Результаты. Вследствие применения термической гелий-кислородной смеси на фоне стандартной терапии ни у одного пациента объективных побочных эффектов, связанных с процедурой, не выявлено. У всех пациентов обнаружены следующие изменения: повышение pО2 /FiO2, SpO2 и уровня лимфоцитов, снижение концентрации С-реактивного белка, восстановление уровней Д-димера, ферритина. Эти признаки статистически значимо изменились в первой группе в течение 3 сут, тогда как во второй группе на 710-е сут терапии. Элиминация вируса SARS-CoV-2 в первой группе происходила в течение 4872 ч от момента начала ингаляции, что подтверждалось методом ПЦР, а во второй в течение 72168 ч. Заключение. Включение ингаляций термической газовой смеси гелия с кислородом (t-Не/О2 ) в стандартную терапию пациентов, переносящих инфекционное заболевание, вызванное SARS-CоV-2, c КТ-признаками пневмонии (КТ2, КТ3), с острой дыхательной недостаточностью улучшает газообмен, способствует ускорению элиминации вируса и опосредованно повышает противовоспалительный эффект

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV

A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross section of the standard model Higgs boson decaying to two photons. The expected exclusion limit at 95% confidence level is between 1.4 and 2.4 times the standard model cross section in the mass range between 110 and 150 GeV. The analysis of the data excludes, at 95% confidence level, the standard model Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The largest excess of events above the expected standard model background is observed for a Higgs boson mass hypothesis of 124 GeV with a local significance of 3.1 sigma. The global significance of observing an excess with a local significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is estimated to be 1.8 sigma. More data are required to ascertain the origin of this excess.Comment: Submitted to Physics Letters

Measurement of the Lambda(b) cross section and the anti-Lambda(b) to Lambda(b) ratio with Lambda(b) to J/Psi Lambda decays in pp collisions at sqrt(s) = 7 TeV

The Lambda(b) differential production cross section and the cross section ratio anti-Lambda(b)/Lambda(b) are measured as functions of transverse momentum pt(Lambda(b)) and rapidity abs(y(Lambda(b))) in pp collisions at sqrt(s) = 7 TeV using data collected by the CMS experiment at the LHC. The measurements are based on Lambda(b) decays reconstructed in the exclusive final state J/Psi Lambda, with the subsequent decays J/Psi to an opposite-sign muon pair and Lambda to proton pion, using a data sample corresponding to an integrated luminosity of 1.9 inverse femtobarns. The product of the cross section times the branching ratio for Lambda(b) to J/Psi Lambda versus pt(Lambda(b)) falls faster than that of b mesons. The measured value of the cross section times the branching ratio for pt(Lambda(b)) > 10 GeV and abs(y(Lambda(b))) < 2.0 is 1.06 +/- 0.06 +/- 0.12 nb, and the integrated cross section ratio for anti-Lambda(b)/Lambda(b) is 1.02 +/- 0.07 +/- 0.09, where the uncertainties are statistical and systematic, respectively.Comment: Submitted to Physics Letters

Search for new physics in events with opposite-sign leptons, jets, and missing transverse energy in pp collisions at sqrt(s) = 7 TeV

A search is presented for physics beyond the standard model (BSM) in final states with a pair of opposite-sign isolated leptons accompanied by jets and missing transverse energy. The search uses LHC data recorded at a center-of-mass energy sqrt(s) = 7 TeV with the CMS detector, corresponding to an integrated luminosity of approximately 5 inverse femtobarns. Two complementary search strategies are employed. The first probes models with a specific dilepton production mechanism that leads to a characteristic kinematic edge in the dilepton mass distribution. The second strategy probes models of dilepton production with heavy, colored objects that decay to final states including invisible particles, leading to very large hadronic activity and missing transverse energy. No evidence for an event yield in excess of the standard model expectations is found. Upper limits on the BSM contributions to the signal regions are deduced from the results, which are used to exclude a region of the parameter space of the constrained minimal supersymmetric extension of the standard model. Additional information related to detector efficiencies and response is provided to allow testing specific models of BSM physics not considered in this paper.Comment: Replaced with published version. Added journal reference and DO

Measurement of isolated photon production in pp and PbPb collisions at sqrt(sNN) = 2.76 TeV

Isolated photon production is measured in proton-proton and lead-lead collisions at nucleon-nucleon centre-of-mass energies of 2.76 TeV in the pseudorapidity range |eta|<1.44 and transverse energies ET between 20 and 80 GeV with the CMS detector at the LHC. The measured ET spectra are found to be in good agreement with next-to-leading-order perturbative QCD predictions. The ratio of PbPb to pp isolated photon ET-differential yields, scaled by the number of incoherent nucleon-nucleon collisions, is consistent with unity for all PbPb reaction centralities.Comment: Submitted to Physics Letters

Charmonium production in Pb-Pb collisions

NA50The elaboration of specific media-planning is necessary to communicate with an opinion leader. Opinion leaders in 27 product categories are selected from a 10,000 sample of French representative consumers. Magazine is the favorite media of opinion leaders; the more important is the number of product categories in which a consumer is leaders, the greater the media consumption. Leaders do not systematically prefer the Internet, their preference appears to be category specific. However, a second study conducted among 600 brand website visitors shows that brand sites represent a major information source for the leaders

Strangeness measurements in NA50 experiment with Pb projectiles

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