501 research outputs found

    The L Word: Nonprofits, Language, and Lobbying

    Get PDF
    Despite the many benefits associated with policy advocacy, many nonprofit organizations do not lobby. Recently, scholars have called attention to the possibility that the vagueness and ambiguity of the term lobbying may hinder policy advocacy activities, though few studies have systematically explored the relationship between nonprofit professionals\u27 perception of this term and political activity. This study explored the social construction of the term lobbying by examining nonprofit leaders\u27 beliefs, attitudes, and behaviors surrounding lobbying activities. Participants reported having a strong aversion to the term lobbying and preferred alternative language to describe their political activities. Implications for practice and research are discussed

    Skewness and kurtosis of mean transverse momentum fluctuations at the LHC energies

    Get PDF
    The first measurements of skewness and kurtosis of mean transverse momentum (怈pT怉) fluctuations are reported in Pbā€“Pb collisions at sNN = 5.02 TeV, Xeā€“Xe collisions at sNN = 5.44 TeV and pp collisions at s=5.02 TeV using the ALICE detector. The measurements are carried out as a function of system size 怈dNch/dĪ·ć€‰|Ī·|<0.51/3, using charged particles with transverse momentum (pT) and pseudorapidity (Ī·), in the range 0.2<3.0 GeV/c and |Ī·|<0.8, respectively. In Pbā€“Pb and Xeā€“Xe collisions, positive skewness is observed in the fluctuations of 怈pT怉 for all centralities, which is significantly larger than what would be expected in the scenario of independent particle emission. This positive skewness is considered a crucial consequence of the hydrodynamic evolution of the hot and dense nuclear matter created in heavy-ion collisions. Furthermore, similar observations of positive skewness for minimum bias pp collisions are also reported here. Kurtosis of 怈pT怉 fluctuations is found to be in good agreement with the kurtosis of Gaussian distribution, for most central Pbā€“Pb collisions. Hydrodynamic model calculations with MUSIC using Monte Carlo Glauber initial conditions are able to explain the measurements of both skewness and kurtosis qualitatively from semicentral to central collisions in Pbā€“Pb system. Color reconnection mechanism in PYTHIA8 model seems to play a pivotal role in capturing the qualitative behavior of the same measurements in pp collisions

    K *(892)Ā± resonance production in Pb-Pb collisions at āˆšsNN=5.02 TeV

    Get PDF
    The production of Kāˆ—(892)Ā± meson resonance is measured at midrapidity (|y|<0.5) in Pb-Pb collisions at sNN=5.02 TeV using the ALICE detector at the CERN Large Hadron Collider. The resonance is reconstructed via its hadronic decay channel Kāˆ—(892)Ā±ā†’KS0Ļ€Ā±. The transverse momentum distributions are obtained for various centrality intervals in the pT range of 0.4-16 GeV/c. Measurements of integrated yields, mean transverse momenta, and particle yield ratios are reported and found to be consistent with previous ALICE measurements for Kāˆ—(892)0 within uncertainties. The pT-integrated yield ratio 2Kāˆ—(892)Ā±/(K++K-) in central Pb-Pb collisions shows a significant suppression at a level of 9.3Ļƒ relative to pp collisions. Thermal model calculations result in an overprediction of the particle yield ratio. Although both hadron resonance gas in partial chemical equilibrium (HRG-PCE) and music + smash simulations consider the hadronic phase, only HRG-PCE accurately represents the measurements, whereas music + smash simulations tend to overpredict the particle yield ratio. These observations, along with the kinetic freeze-out temperatures extracted from the yields measured for light-flavored hadrons using the HRG-PCE model, indicate a finite hadronic phase lifetime, which decreases with increasing collision centrality percentile. The pT-differential yield ratios 2Kāˆ—(892)Ā±/(K++K-) and 2Kāˆ—(892)Ā±/(Ļ€++Ļ€-) are presented and compared with measurements in pp collisions at s=5.02 TeV. Both particle ratios are found to be suppressed by up to a factor of five at pT<2.0 GeV/c in central Pb-Pb collisions and are qualitatively consistent with expectations for rescattering effects in the hadronic phase. The nuclear modification factor (RAA) shows a smooth evolution with centrality and is found to be below unity at pT>8 GeV/c, consistent with measurements for other light-flavored hadrons. The smallest values are observed in most central collisions, indicating larger energy loss of partons traversing the dense medium

    Emergence of Long-Range Angular Correlations in Low-Multiplicity Proton-Proton Collisions

    Get PDF
    This Letter presents the measurement of near-side associated per-trigger yields, denoted ridge yields, from the analysis of angular correlations of charged hadrons in proton-proton collisions at s=13 TeV. Long-range ridge yields are extracted for pairs of charged particles with a pseudorapidity difference of 1.4<|Ī”Ī·|<1.8 and a transverse momentum of 1<2 GeV/c, as a function of the charged-particle multiplicity measured at midrapidity. This Letter extends the measurements of the ridge yield to the low multiplicity region, where in hadronic collisions it is typically conjectured that a strongly interacting medium is unlikely to be formed. The precision of the new low multiplicity results allows for the first direct quantitative comparison with the results obtained in e+e- collisions at s=91 GeV and s=183-209 GeV, where initial-state effects such as preequilibrium dynamics and collision geometry are not expected to play a role. In the multiplicity range

    Multiplicity and event-scale dependent flow and jet fragmentation in pp collisions at āˆšs=13 TeV and in p-Pb collisions at āˆšsNN=5.02 TeV

    Get PDF
    Long- and short-range correlations for pairs of charged particles are studied via two-particle angular correlations in pp collisions at s = 13 TeV and pā€“Pb collisions at sNN = 5.02 TeV. The correlation functions are measured as a function of relative azimuthal angle āˆ†Ļ† and pseudorapidity separation āˆ†Ī· for pairs of primary charged particles within the pseudorapidity interval |Ī·| < 0.9 and the transverse-momentum interval 1 < pT< 4 GeV/c. Flow coefficients are extracted for the long-range correlations (1.6 < |āˆ†Ī·| < 1.8) in various high-multiplicity event classes using the low-multiplicity template fit method. The method is used to subtract the enhanced yield of away-side jet fragments in high-multiplicity events. These results show decreasing flow signals toward lower multiplicity events. Furthermore, the flow coefficients for events with hard probes, such as jets or leading particles, do not exhibit any significant changes compared to those obtained from high-multiplicity events without any specific event selection criteria. The results are compared with hydrodynamic-model calculations, and it is found that a better understanding of the initial conditions is necessary to describe the results, particularly for low-multiplicity events

    Search for jet quenching effects in high-multiplicity pp collisions at āˆšs=13 TeV via di-jet acoplanarity

    Get PDF
    The ALICE Collaboration reports a search for jet quenching effects in high-multiplicity (HM) proton-proton collisions at s = 13 TeV, using the semi-inclusive azimuthal-difference distribution āˆ†Ļ† of charged-particle jets recoiling from a high transverse momentum (high-pT,trig) trigger hadron. Jet quenching may broaden the āˆ†Ļ† distribution measured in HM events compared to that in minimum bias (MB) events. The measurement employs a pT,trig-differential observable for data-driven suppression of the contribution of multiple partonic interactions, which is the dominant background. While azimuthal broadening is indeed observed in HM compared to MB events, similar broadening for HM events is observed for simulations based on the PYTHIA 8 Monte Carlo generator, which does not incorporate jet quenching. Detailed analysis of these data and simulations show that the azimuthal broadening is due to bias of the HM selection towards events with multiple jets in the final state. The identification of this bias has implications for all jet quenching searches where selection is made on the event activity

    Observation of abnormal suppression of f0(980) production in p-Pb collisions at āˆšsNN=5.02 TeV

    Get PDF
    The dependence of f0(980) production on the final-state charged-particle multiplicity in pā€“Pb collisions at sNN=5.02 TeV is reported. The production of f0(980) is measured with the ALICE detector via the f0(980)ā†’Ļ€+Ļ€āˆ’ decay channel in a midrapidity region of āˆ’0.5<0. Particle yield ratios of f0(980) to Ļ€ and KāŽ(892)0 are found to be decreasing with increasing charged-particle multiplicity. The magnitude of the suppression of the f0(980)/Ļ€ and f0(980)/KāŽ(892)0 yield ratios is found to be dependent on the transverse momentum pT, suggesting different mechanisms responsible for the measured effects. Furthermore, the nuclear modification factor QpPb of f0(980) is measured in various multiplicity ranges. The QpPb shows a strong suppression of the f0(980) production in the pT region up to about 4 GeV/c. The results on the particle yield ratios and QpPb for f0(980) may help to understand the late hadronic phase in pā€“Pb collisions and the nature of the internal structure of f0(980) particle

    f0(980) production in inelastic pp collisions at s = 5.02 TeV

    Get PDF
    The measurement of the production of f0(980) in inelastic pp collisions at sqrt(s) = 5.02 TeV is presented. This is the first reported measurement of inclusive f0(980) yield at LHC energies. The production is measured at midrapidity, |y| pi+pi- hadronic decay channel using the ALICE detector. The pT-differential yields are compared to those of pions, protons and Ļ• mesons as well as to predictions from the HERWIG 7.2 QCD-inspired Monte Carlo event generator and calculations from a coalescence model that uses the AMPT model as an input. The ratio of the pT-integrated yield of f0(980) relative to pions is compared to measurements in e+e- and pp collisions at lower energies and predictions from statistical hadronisation models and HERWIG 7.2. A mild collision energy dependence of the f0(980) to pion production is observed in pp collisions from SPS to LHC energies. All considered models underpredict the pT-integrated 2f0(980)/(pi+ + pi-) ratio. The prediction from the canonical statistical hadronisation model assuming a zero total strangeness content of f0(980) is consistent with the data within 1.9Ļƒ and is the closest to the data. The results provide an essential reference for future measurements of the particle yield and nuclear modification in pā€“Pb and Pbā€“Pb collisions, which have been proposed to be instrumental to probe the elusive nature and quark composition of the f0(980) scalar meson
    • ā€¦
    corecore