1,006 research outputs found

    Prospects for intermediate mass black hole binary searches with advanced gravitational-wave detectors

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    We estimated the sensitivity of the upcoming advanced, ground-based gravitational-wave observatories (the upgraded LIGO and Virgo and the KAGRA interferometers) to coalescing intermediate mass black hole binaries (IMBHB). We added waveforms modeling the gravitational radiation emitted by IMBHBs to detectors' simulated data and searched for the injected signals with the coherent WaveBurst algorithm. The tested binary's parameter space covers non-spinning IMBHBs with source-frame total masses between 50 and 1050 M\text{M}_{\odot} and mass ratios between 1/61/6 and 1\,. We found that advanced detectors could be sensitive to these systems up to a range of a few Gpc. A theoretical model was adopted to estimate the expected observation rates, yielding up to a few tens of events per year. Thus, our results indicate that advanced detectors will have a reasonable chance to collect the first direct evidence for intermediate mass black holes and open a new, intriguing channel for probing the Universe over cosmological scales.Comment: 9 pages, 4 figures, corrected the name of one author (previously misspelled

    Enhancing the significance of gravitational wave bursts through signal classification

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    The quest to observe gravitational waves challenges our ability to discriminate signals from detector noise. This issue is especially relevant for transient gravitational waves searches with a robust eyes wide open approach, the so called all- sky burst searches. Here we show how signal classification methods inspired by broad astrophysical characteristics can be implemented in all-sky burst searches preserving their generality. In our case study, we apply a multivariate analyses based on artificial neural networks to classify waves emitted in compact binary coalescences. We enhance by orders of magnitude the significance of signals belonging to this broad astrophysical class against the noise background. Alternatively, at a given level of mis-classification of noise events, we can detect about 1/4 more of the total signal population. We also show that a more general strategy of signal classification can actually be performed, by testing the ability of artificial neural networks in discriminating different signal classes. The possible impact on future observations by the LIGO-Virgo network of detectors is discussed by analysing recoloured noise from previous LIGO-Virgo data with coherent WaveBurst, one of the flagship pipelines dedicated to all-sky searches for transient gravitational waves

    The role of spiritual formation in the education of modern human beings : a European Christian perspective

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    One of the most considerable changes in the contemporary European educational mentality is a person’s disconnection from spiritual life. Christian formation has been replaced with religious pluralism, in terms of syncretism influenced by global economic ideologies. Some consequences are low resilience and low spiritual resistance to contemporary challenges, associated with mental traumas or social behaviour deficits. Is it possible to restore the modern person’s spiritual education? There is no evolution in the modern individual’s social life without a horizon of spiritual expectation and fulfilment, different from the strictly material one. Moreover, conscious education cannot deprive people of cultivating the spiritual part of their consciousness from which the real values of existence are born. A series of arguments for renewing the relation between school and the mature, Scripture-based Christian thinking in the spirit of the European pedagogy are revealed by the factual historical analyses. Both Eastern and Western European experiences have met after 13 years of evolving into two antagonist geopolitical spheres. Their lessons in the education field could be an appropriate model, academically applied at the cultural mentality and the European pedagogy level. CONTRIBUTION : With this study, I want to highlight the historical and conceptual frameworks of the Christian religious education meaning in the context of the rediscovery of Orthodox Christianity by the international theological culture in post-communism. Orthodox Christianity, forgotten in dictionaries and syntheses by the Western theological elite, brings in a spiritualisation of education according to the Lord Jesus Christ’s Gospel and not of the ideological cultural interests.The author is participating as the research associate of Dean Prof. Dr Jerry Pillay, Faculty of Theology and Religion, University of Pretoria.Special Collection: Lucian Blaga University, Sibiu, Romania, sub-edited by Daniel Buda (Lucian Blaga University) and Jerry Pillay (University of Pretoria).http://www.hts.org.zaam2022Dogmatics and Christian Ethic

    Measurement of the ttbar Production Cross Section in ppbar Collisions at sqrt(s) = 1.96 TeV

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    We present a measurement of the top quark pair production cross section in ppbar collisions at sqrt(s)=1.96 TeV using 318 pb^{-1} of data collected with the Collider Detector at Fermilab. We select ttbar decays into the final states e nu + jets and mu nu + jets, in which at least one b quark from the t-quark decays is identified using a secondary vertex-finding algorithm. Assuming a top quark mass of 178 GeV/c^2, we measure a cross section of 8.7 +-0.9 (stat) +1.1-0.9 (syst) pb. We also report the first observation of ttbar with significance greater than 5 sigma in the subsample in which both b quarks are identified, corresponding to a cross section of 10.1 +1.6-1.4(stat)+2.0-1.3 (syst) pb.Comment: Accepted for publication in Physics Review Letters, 7 page

    Search for Second-Generation Scalar Leptoquarks in ppˉ\bm{p \bar{p}} Collisions at s\sqrt{s}=1.96 TeV

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    Results on a search for pair production of second generation scalar leptoquark in ppˉp \bar{p} collisions at s\sqrt{s}=1.96 TeV are reported. The data analyzed were collected by the CDF detector during the 2002-2003 Tevatron Run II and correspond to an integrated luminosity of 198 pb1^{-1}. Leptoquarks (LQ) are sought through their decay into (charged) leptons and quarks, with final state signatures represented by two muons and jets and one muon, large transverse missing energy and jets. We observe no evidence for LQLQ production and derive 95% C.L. upper limits on the LQLQ production cross sections as well as lower limits on their mass as a function of β\beta, where β\beta is the branching fraction for LQμqLQ \to \mu q.Comment: 9 pages (3 author list) 5 figure

    Search for gravitational waves associated with the InterPlanetary Network short gamma ray bursts

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    We outline the scientific motivation behind a search for gravitational waves associated with short gamma ray bursts detected by the InterPlanetary Network (IPN) during LIGO's fifth science run and Virgo's first science run. The IPN localisation of short gamma ray bursts is limited to extended error boxes of different shapes and sizes and a search on these error boxes poses a series of challenges for data analysis. We will discuss these challenges and outline the methods to optimise the search over these error boxes.Comment: Methods paper; Proceedings for Eduardo Amaldi 9 Conference on Gravitational Waves, July 2011, Cardiff, U

    Implementation and testing of the first prompt search for gravitational wave transients with electromagnetic counterparts

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    Aims. A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods. During two observing periods (Dec 17 2009 to Jan 8 2010 and Sep 2 to Oct 20 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability to reconstruct source positions correctly. Results. For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with ~50% or better probability with a few pointings of wide-field telescopes.Comment: 17 pages. This version (v2) includes two tables and 1 section not included in v1. Accepted for publication in Astronomy & Astrophysic

    Эффективность и безопасность длительного применения бронхорасширяющих средств и фенспирида при хронической обструктивной болезни легких

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    Catedra Medicină internă nr. 6, USMF „Nicolae Testemiţanu”, Universitatea Liberă Internaţională a Moldovei, Conferinţa Ştiinţifico-Practică „Medicina modernă, actualităţi şi perspective”, consacrată aniversării de 40 de ani ai Spitalului Clinic al Ministerului Sănătăţii, 27-28 mai, 2010, Chişinău, Republica MoldovaThe study included 60 patients with COPD grade II. In the first stage of the study, the patients were monitored during exacerbation of COPD; in stage 2 – in ambulatory conditions (for 6 months) during clinical remission of the disease. Depending on the administered treatment the patients were randomized into 3 groups. Group I included 20 patients with COPD who administered bronchodilator Salmeterol, group II – 20 patients who received the combined drug Seretide, group III – 20 patients with COPD who received Fenspirid. Administration of Seretide and Fenspirid contributed to a statistically significant decrease of dyspnoea and the concentration of systemic inflammation markers, decreased the frequency of exacerbations, improved the indices of FEV, enhanced the effectiveness of the basic curative therapy and improved patients’ quality of life.Обследовано 60 больных ХОБЛ II степени тяжести. На первом этапе, в период обострения хронической обструктивной болезни легких, проводился мониторинг пациентов в условиях стационара, на втором – в амбулаторных условиях в период клинической ремиссии заболевания (в течение 6 месяцев). В зависимости от метода лечения методом рандомизации были сформированы 3 группы наблюдения. В I группу были включены 20 пациентов с ХОБЛ, получавших бронходилататор Сальметерол, во II группу – 20 пациентов, получавших комбинированный препарат Серетайд, в III группу – 20 пациентов, получавших Фенспирид. Применение в комплексной терапии хронической обструктивной болезни легких препаратов Серетайд и Фенспирид способствовало статистически достоверному уменьшению одышки и концентрации системных маркеров воспаления, улучшению ОФВ1 и снижению частоты обострений

    Gravitational Waves From Known Pulsars: Results From The Initial Detector Era

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    We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom

    Measurement of the Dipion Mass Spectrum in X(3872) -> J/Psi Pi+ Pi- Decays

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    We measure the dipion mass spectrum in X(3872)--> J/Psi Pi+ Pi- decays using 360 pb-1 of pbar-p collisions at 1.96 TeV collected with the CDF II detector. The spectrum is fit with predictions for odd C-parity (3S1, 1P1, and 3DJ) charmonia decaying to J/Psi Pi+ Pi-, as well as even C-parity states in which the pions are from Rho0 decay. The latter case also encompasses exotic interpretations, such as a D0-D*0Bar molecule. Only the 3S1 and J/Psi Rho hypotheses are compatible with our data. Since 3S1 is untenable on other grounds, decay via J/Psi Rho is favored, which implies C=+1 for the X(3872). Models for different J/Psi-Rho angular momenta L are considered. Flexibility in the models, especially the introduction of Rho-Omega interference, enable good descriptions of our data for both L=0 and 1.Comment: 7 pages, 4 figures -- Submitted to Phys. Rev. Let
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