Browsing by Subject "COLLISIONS"

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  • Mäntysaari, Heikki; Schenke, Björn (2020)
    We show how exclusive vector meson production off light ions can be used to probe the spatial distribution of small-x gluons in the deuteron and He-3 wave functions. In particular, we demonstrate how short-range repulsive nucleon-nucleon interactions affect the predicted coherent J/Psi production spectra. Fluctuations of the nucleon substructure are shown to have a significant effect on the incoherent cross section above vertical bar t vertical bar greater than or similar to 0.2 GeV2. By explicitly performing the Jalilian-Marian-Iancu-McLerran-Weigert-Leonidov-Kovner (JIMWLK) evolution, we predict the x dependence of coherent and incoherent cross sections in the electron-ion collider energy range. In addition to the increase of the average size of the nucleus with decreasing x, both the growth of the nucleons and subnucleonic hot spots are visible in the cross sections. The decreasing length scale of color charge fluctuations with decreasing x is also present, but may not be observable for vertical bar t vertical bar <1 GeV2, if subnucleonic spatial fluctuations are present.
  • Esmaeilikia, Mahsa; Radun, Igor; Grzebieta, Raphael; Olivier, Jake (2019)
    A long-standing argument against bicycle helmet use is the risk compensation hypothesis, i.e., increased feelings of safety caused by wearing a helmet results in cyclists exhibiting more risky behaviour. However, past studies have found helmet wearing is not associated with risky behaviour, e.g., committing a traffic violation was positively associated with a lower frequency of helmet use. There is a lack of consensus in the research literature regarding bicycle helmet use and the risk compensation hypothesis, although this gap in knowledge was identified in the early 2000s. This is the first study to carry out a systematic review of the literature to assess whether helmet wearing is associated with risky behaviour. Two study authors systematically searched the peer-reviewed literature using five research databases (EMBASE, MEDLINE, COMPENDEX, SCOPUS, and WEB OF SCIENCE) and identified 141 unique articles and four articles from other sources. Twenty-three articles met inclusion criteria and their findings were summarised. Eighteen studies found no supportive evidence helmet use was positively associated with risky behaviour, while three studies provided mixed findings, i.e., results for and against the hypothesis. For many of these studies, bicycle helmet wearing was associated with safer cycling behaviour. Only two studies conducted from the same research lab provided evidence to support the risk compensation hypothesis. In sum, this systematic review found little to no support for the hypothesis bicycle helmet use is associated with engaging in risky behaviour. (C) 2018 The Authors. Published by Elsevier Ltd.
  • Boguslavski, K.; Kurkela, A.; Lappi, Tuomas; Peuron, Jarkko (2021)
    Motivated by the initial stages of high-energy heavy-ion collisions, we study excitations of far-from-equilibrium 2+1 dimensional gauge theories using classical-statistical lattice simulations. We evolve field perturbations over a strongly overoccupied background undergoing self-similar evolution. While in 3+1D the excitations are described by hard-thermal loop theory, their structure in 2+1D is nontrivial and nonperturbative. These nonperturbative interactions lead to broad excitation peaks in spectral and statistical correlation functions. Their width is comparable to the frequency of soft excitations, demonstrating the absence of soft quasiparticles in these theories. Our results also suggest that excitations at higher momenta are sufficiently long-lived, such that an effective kinetic theory description for 2+1 dimensional Glasma-like systems may exist, but its collision kernel must be nonperturbatively determined.
  • Dumitru, Adrian; Mäntysaari, Heikki; Paatelainen, Risto (2021)
    Color charge correlators provide fundamental information about the proton structure. In this Letter, we evaluate numerically two-point color charge correlations in a proton on the light cone including the next-to-leading order corrections due to emission or exchange of a perturbative gluon. The non-perturbative valence quark structure of the proton is modelled in a way consistent with high-x proton structure data. Our results show that the correlator exhibits startlingly non-trivial behavior at large momentum transfer or central impact parameters, and that the color charge correlation depends not only on the impact parameter but also on the relative transverse momentum of the two gluon probes and their relative angle. Furthermore, from the two-point color charge correlator, we compute the dipole scattering amplitude. Its azimuthal dependence differs significantly from a impact parameter dependent McLerran-Venugopalan model based on geometry. Our results also provide initial conditions for Balitsky-Kovchegov evolution of the dipole scattering amplitude. These initial conditions depend not only on the impact parameter and dipole size vectors, but also on their relative angle and on the light-cone momentum fraction x in the target. (C) 2021 The Author(s). Published by Elsevier B.V.
  • The ATLAS collaboration; The CMS collaboration; Aad, G.; Aaboud, M.; Sirunyan, A. M.; Eerola, P.; Kirschenmann, H.; Pekkanen, J.; Voutilainen, M.; Havukainen, J.; Heikkilä, J. K.; Järvinen, T.; Karimäki, V.; Kinnunen, R.; Lampén, T.; Lassila-Perini, K.; Laurila, S.; Lehti, S.; Lindén, T.; Luukka, P.; Mäenpää, T.; Siikonen, H.; Tuominen, E.; Tuominiemi, J.; Tuuva, T. (2019)
    This paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at = 7 and 8 TeV corresponding to integrated luminosities of 1.17 to 5.1 fb(-1) at = 7 TeV and 12.2 to 20.3 fb(-1) at = 8 TeV. These combinations are performed per centre-of-mass energy and for each production mode: t-channel, tW, and s-channel. The combined t-channel cross-sections are 67.5 +/- 5.7 pb and 87.7 +/- 5.8 pb at = 7 and 8 TeV respectively. The combined tW cross-sections are 16.3 +/- 4.1 pb and 23.1 +/- 3.6 pb at = 7 and 8 TeV respectively. For the s-channel cross-section, the combination yields 4.9 +/- 1.4 pb at = 8 TeV. The square of the magnitude of the CKM matrix element V-tb multiplied by a form factor f(LV) is determined for each production mode and centre-of-mass energy, using the ratio of the measured cross-section to its theoretical prediction. It is assumed that the top-quark-related CKM matrix elements obey the relation |V-td|, |V-ts| << |V-tb|. All the |f(LV)V(tb)|(2) determinations, extracted from individual ratios at = 7 and 8 TeV, are combined, resulting in |f(LV)V(tb)| = 1.02 +/- 0.04 (meas.) +/- 0.02 (theo.). All combined measurements are consistent with their corresponding Standard Model predictions.
  • Albacete, Javier L.; Niemi, Harri; Petersen, Hannah; Soto-Ontoso, Alba (2019)
    We present a systematic study on the influence of spatial correlations between the proton constituents, in our case gluonic hot spots, their size and their number on the symmetric cumulant SC(2, 3), at the eccentricity level, within a Monte Carlo Glauber framework [1]. When modeling the proton as composed by 3 gluonic hot spots, the most common assumption in the literature, we find that the inclusion of spatial correlations is indispensable to reproduce the negative sign of SC(2, 3) in the highest centrality bins as dictated by data. Further, the subtle interplay between the different scales of the problem is discussed. To conclude, the possibility of feeding a 2+1D viscous hydrodynamic simulation with our entropy profiles is exposed.
  • Tiurev, Konstantin; Kuopanportti, Pekko; Möttönen, Mikko (2019)
    We theoretically demonstrate that a pair of Dirac monopoles with opposite synthetic charges can be created within a single spin-1 Bose-Einstein condensate by steering the spin degrees of freedom by external magnetic fields. Although the net synthetic magnetic charge of this configuration vanishes, both the monopole and the antimonopole are accompanied by vortex filaments carrying opposite angular momenta. Such a Dirac dipole can be realized experimentally by imprinting a spin texture with a nonlinear magnetic field generated by a pair of coils in a modified Helmholtz configuration. We also investigate the case where the initial state for the dipole-creation procedure is pierced by a quantized vortex line with a winding number kappa. It is shown that if kappa = -1, the resulting monopole and antimonopole lie along the core of a singly quantized vortex whose sign is reversed at the locations of the monopoles. For kappa = -2, the monopole and antimonopole are connected by a vortex line segment carrying two quanta of angular momentum, and hence the dipole as a whole is an isolated configuration. In addition, we simulate the long-time evolution of the dipoles in the magnetic field used to create them. For kappa = 0, each of the semi-infinite doubly quantized vortices splits into two singly quantized vortices, as in the case of a single Dirac monopole. For kappa = -1 and kappa = -2, the initial vortices deform into a vortex with a kink and a vortex ring, respectively.
  • Mäntysaari, Heikki; Mueller, Niklas; Schenke, Björn (2019)
    Experimental processes that are sensitive to partonWigner distributions provide a powerful tool to advance our understanding of proton structure. In this work, we compute gluon Wigner and Husimi distributions of protons within the color glass condensate framework, which includes a spatially dependent McLerran-Venugopalan initial configuration and the explicit numerical solution of the Jalilian-Marian-IancuMcLerran-Weigert-Leonidov-Kovner equations. We determine the leading anisotropy of the Wigner and Husimi distributions as a function of the angle between the impact parameter and transverse momentum. We study experimental signatures of these angular correlations at a proposed electron-ion collider by computing coherent diffractive dijet production cross sections in e + p collisions within the same framework. Specifically, we predict the elliptic modulation of the cross section as a function of the relative angle between the nucleon recoil and dijet transversemomentumfor a wide kinematical range. We further predict its dependence on the collision energy, which is dominated by the growth of the proton with decreasing x.
  • Stolzenburg, Dominik; Simon, Mario; Ranjithkumar, Ananth; Kuerten, Andreas; Lehtipalo, Katrianne; Gordon, Hamish; Ehrhart, Sebastian; Finkenzeller, Henning; Pichelstorfer, Lukas; Nieminen, Tuomo; Brilke, Sophia; Xiao, Mao; Amorim, Antonio; Baalbaki, Rima; Baccarini, Andrea; Beck, Lisa; Brakling, Steffen; Murillo, Lucia Caudillo; Chen, Dexian; Chu, Biwu; Dada, Lubna; Dias, Antonio; Dommen, Josef; Duplissy, Jonathan; El Haddad, Imad; Fischer, Lukas; Carracedo, Loic Gonzalez; Heinritzi, Martin; Kim, Changhyuk; Koenig, Theodore K.; Kong, Weimeng; Lamkaddam, Houssni; Lee, Chuan Ping; Leiminger, Markus; Li, Zijun; Makhmutov, Vladimir; Manninen, Hanna E.; Marie, Guillaume; Marten, Ruby; Mueller, Tatjana; Nie, Wei; Partoll, Eva; Petaja, Tuukka; Pfeifer, Joschka; Philippov, Maxim; Rissanen, Matti P.; Rorup, Birte; Schobesberger, Siegfried; Schuchmann, Simone; Shen, Jiali; Sipila, Mikko; Steiner, Gerhard; Stozhkov, Yuri; Tauber, Christian; Tham, Yee Jun; Tome, Antonio; Vazquez-Pufleau, Miguel; Wagner, Andrea C.; Wang, Mingyi; Wang, Yonghong; Weber, Stefan K.; Wimmer, Daniela; Wlasits, Peter J.; Wu, Yusheng; Ye, Qing; Zauner-Wieczorek, Marcel; Baltensperger, Urs; Carslaw, Kenneth S.; Curtius, Joachim; Donahue, Neil M.; Flagan, Richard C.; Hansel, Armin; Kulmala, Markku; Lelieveld, Jos; Volkamer, Rainer; Kirkby, Jasper; Winkler, Paul M.; He, Xucheng (2020)
    In the present-day atmosphere, sulfuric acid is the most important vapour for aerosol particle formation and initial growth. However, the growth rates of nanoparticles (<10 nm) from sulfuric acid remain poorly measured. Therefore, the effect of stabilizing bases, the contribution of ions and the impact of attractive forces on molecular collisions are under debate. Here, we present precise growth rate measurements of uncharged sulfuric acid particles from 1.8 to 10 nm, performed under atmospheric conditions in the CERN (European Organization for Nuclear Research) CLOUD chamber. Our results show that the evaporation of sulfuric acid particles above 2 nm is negligible, and growth proceeds kinetically even at low ammonia concentrations. The experimental growth rates exceed the hard-sphere kinetic limit for the condensation of sulfuric acid. We demonstrate that this results from van derWaals forces between the vapour molecules and particles and disentangle it from charge-dipole interactions. The magnitude of the enhancement depends on the assumed particle hydration and collision kinetics but is increasingly important at smaller sizes, resulting in a steep rise in the observed growth rates with decreasing size. Including the experimental results in a global model, we find that the enhanced growth rate of sulfuric acid particles increases the predicted particle number concentrations in the upper free troposphere by more than 50 %.
  • Antchev, G.; Garcia, F.; Heino, J.; Lauhakangas, R.; Naaranoja, T.; Oljemark, F.; Orava, R.; Österberg, K.; Saarikko, H.; Welti, J.; TOTEM Collaboration (2015)
    The TOTEM experiment has made a precise measurement of the elastic proton proton differential cross-section at the centre-of-mass energy root s = 8 TeV based on a high-statistics data sample obtained with the beta* = 90 m optics. Both the statistical and systematic uncertainties remain below 1%, except for the t-independent contribution from the overall normalisation. This unprecedented precision allows to exclude a purely exponential differential cross-section in the range of four-momentum transfer squared 0.027 <vertical bar t vertical bar <0.2 GeV2 with a significance greater than 7 sigma. Two extended parametrisations, with quadratic and cubic polynomials in the exponent, are shown to be well compatible with the data. Using them for the differential cross-section extrapolation to t = 0, and further applying the optical theorem, yields total cross-section estimates of (101.5 +/- 2.1) mb and (101.9 +/- 2.1) mb, respectively, in agreement with previous TOTEM measurements. (C) 2015 The Authors. Published by Elsevier B.V.
  • The CMS collaboration; Sirunyan, A. M.; Eerola, P.; Kirschenmann, H.; Pekkanen, J.; Voutilainen, M.; Havukainen, J.; Heikkilä, J. K.; Järvinen, T.; Karimäki, V.; Kinnunen, R.; Lampén, T.; Lassila-Perini, K.; Laurila, S.; Lehti, S.; Lindén, T.; Luukka, P.; Siikonen, H.; Tuominen, E.; Tuominiemi, J.; Tuuva, T. (2018)
    A search for the standard model (SM) Higgs boson (H) decaying to b(b)over-bar when produced in association with an electroweak vector boson is reported for the following processes: Z(vv)H, W(mu v)H, W(ev)H, Z(mu mu)H, and Z(ee)H. The search is performed in data samples corresponding to an integrated luminosity of 35.9 f( -1) at root s = 13 TeV recorded by the CMS experiment at the LHC during Run 2 in 2016. An excess of events is observed in data compared to the expectation in the absence of a H -> b(b)over-bar, signal. The significance of this excess is 3.3 standard deviations, where the expectation from SM Higgs boson production is 2.8. The signal strength corresponding to this excess, relative to that of the SM Higgs boson production, is 1.2 +/- 0.4. When combined with the Run 1 measurement of the same processes, the signal significance is 3.8 standard deviations with 3.8 expected. The corresponding signal strength, relative to that of the SM Higgs boson, is 1.06(-0.29)(+0.31). (C) 2018 The Author(s). Published by Elsevier B.V.
  • Mäntysaari, Heikki; Penttala, Jani (2021)
    We calculate exclusive production of a longitudinally polarized heavy vector meson at next-to-leading order in the dipole picture. The large quark mass allows us to separately include both the first QCD correction proportional to the coupling constant alpha(s), and the first relativistic correction suppressed by the quark velocity v(2). Both of these corrections are found to be numerically important in J/psi production. The results obtained are directly suitable for phenomenological calculations. We also demonstrate how vector meson production provides complementary information to structure function analyses when one extracts the initial condition for the energy evolution of the proton small-x structure. (C) 2021 The Author(s). Published by Elsevier B.V.
  • The ALICE collaboration; Acharya, S.; Adamova, D.; Kim, D. J.; Krizek, F.; Novitzky, Norbert; Onnerstad, A.; Parkkila, J. E.; Rytkönen, Heidi Maria; Räsänen, Sami; Saarimäki, Oskari Antti Matti; Slupecki, M.; Trzaska, W. H. (2021)
    This Letter presents the first experimental evidence of the attractive strong interaction between a proton and a phi meson. The result is obtained from two-particle correlations of combined p-phi circle plus (p) over bar-phi pairs measured in high-multiplicity pp collisions at root s = 13 TeV by the ALICE Collaboration. The spin-averaged scattering length and effective range of the p-phi interaction are extracted from the fully corrected correlation function employing the Lednicky-Lyuboshits approach. In particular, the imaginary part of the scattering length vanishes within uncertainties, indicating that inelastic processes do not play a prominent role for the p-phi interaction. These data demonstrate that the interaction is dominated by elastic p-phi scattering. Furthermore, an analysis employing phenomenological Gaussian-and Yukawa-type potentials is conducted. Under the assumption of the latter, the N-phi coupling constant is found to be g(N-phi) = 0.14 +/- 0.03(stat) +/- 0.02(syst). This work provides valuable experimental input to accomplish a self-consistent description of the N-phi interaction, which is particularly relevant for the more fundamental studies on partial restoration of chiral symmetry in nuclear medium.
  • The ALICE collaboration; Acharya, S.; Adamova, D.; Kim, D. J.; Krizek, F.; Novitzky, Norbert; Onnerstad, A.; Parkkila, J. E.; Rytkönen, Heidi Maria; Räsänen, Sami; Saarimäki, Oskari Antti Matti; Slupecki, M.; Trzaska, W. H. (2022)
    The interaction of Lambda and Sigma hyperons (Y) with nucleons (N) is strongly influenced by the coupled-channel dynamics. Due to the small mass difference of the N Lambda and N Sigma systems, the sizable coupling strength of the N Sigma N Lambda processes constitutes a crucial element in the determination of the N Lambda interaction. In this letter we present the most precise measurements on the interaction of p Lambda pairs, from zero relative momentum up to the opening of the N Sigma channel. The correlation function in the relative momentum space for p Lambda circle plus (p) over bar(Lambda) over bar pairs measured in high-multiplicity triggered pp collisions at root s = 13 TeV at the LHC is reported. The opening of the inelastic N Sigma channels is visible in the extracted correlation function as a cusp-like structure occurring at relative momentum k* = 289 MeV/c. This represents the first direct experimental observation of the N Sigma N Lambda coupled channel in the p Lambda system. The correlation function is compared with recent chiral effective field theory calculations, based on different strengths of the N Sigma N Lambda transition potential. A weaker coupling, as possibly supported by the present measurement, would require a more repulsive three-body NN Lambda interaction for a proper description of the Lambda in-medium properties, which has implications on the nuclear equation of state and for the presence of hyperons inside neutron stars. (C) 2022 European Organization for Nuclear Research, ALICE. Published by Elsevier B.V.
  • Kajantie, K.; McLerran, Larry D.; Paatelainen, Risto (2019)
    We consider an initially at rest colored particle which is struck by an ultrarelativistic nucleus. The particle is treated classically with respect to both its motion and its color charge. The nucleus is treated as a sheet of colored glass within the context of the color glass condensate framework. We compute both the momentum and coordinates of the struck classical particle and the emitted radiation. Our computations generalize the classic electrodynamics computation of the radiation of an accelerated charged particle to include the radiation induced by the charged gluon field. This latter contribution adds to the classic electrodynamics result and produces a gluon rapidity distribution that is roughly constant as a function of rapidity at rapidities far from the fragmentation region of the struck particles. These computations may form the basis of a first principles treatment for the initial conditions for the evolution of matter produced in the fragmentation region of asymptotically high energy collisions.
  • Ducloué, B.; Szymanowski, L.; Wallon, S. (2016)
    We study the production of two forward jets with a large interval of rapidity at hadron colliders, which was proposed by Mueller and Navelet as a possible test of the high energy dynamics of QCD, within a complete next-to-leading logarithm framework. We show that using the Brodsky-Lepage-Mackenzie procedure to fix the renormalization scale leads to a very good description of the recent CMS data at the LHC for the azimuthal correlations of the jets. We show that the inclusion of next-to-leading order corrections to the jet vertex significantly reduces the importance of energy-momentum non-conservation which is inherent to the BFKL approach, for an asymmetric jet configuration. Finally, we argue that the double parton scattering contribution is negligible in the kinematics of actual CMS measurements.
  • Fomete, Sandra K. W.; Johnson, Jack S.; Myllys, Nanna; Neefjes, Ivo; Reischl, Bernhard; Jen, Coty N. (2022)
    Atmospheric nucleation from precursor gases is a significant source of cloud condensation nuclei in the troposphere and thus can affect the Earth's radiative balance. Sulfuric acid, ammonia, and amines have been identified as key nucleation precursors in the atmosphere. Studies have also shown that atmospheric ions can react with sulfuric acid to form stable clusters in a process referred to as ion-induced nucleation (IIN). IIN follows similar reaction pathways as chemical ionization, which is used to detect and measure nucleation precursors via atmospheric pressure chemical ionization mass spectrometers. The rate at which ions form clusters depends on the ion-molecule rate constant. However, the rate constant varies based on the ion composition, which is often not known in the atmosphere. Previous studies have examined ion-molecule rate constants for sulfuric acid and nitrate ions but not for other atmospherically relevant ions like acetate. We report the relative rate constants of ion- molecule reactions between nitrate and acetate ions reacting with sulfuric acid. The ion- molecule rate constant for acetate and sulfuric acid is estimated to be a factor of 1.9-2.4 times higher than that of the known rate constant for nitrate and sulfuric acid. Using quantum chemistry, we find that acetate has a higher dipole moment and polarizability than nitrate. This may contribute to an increase in the collision cross-sectional area between acetate and sulfuric acid and lead to a greater reaction rate constant than nitrate. The ion- molecule rate constant for acetate with sulfuric acid will help quantify the contribution of acetate ions to atmospheric ion-induced new particle formation.
  • Niemi, H.; Eskola, K. J.; Paatelainen, R.; Tuominen, K. (2019)
    We present the latest results from the NLO pQCD + saturation + viscous hydrodynamics (EbyE NLO EKRT) model. The parameters in the EKRT saturation model are fixed by the charged hadron multiplicity in the 0-5 % 2.76 TeV Pb+Pb collisions. The root s, A and centrality dependence of the initial particle production follows then from the QCD dynamics of the model. This allows us to predict the root s and A dependence of the particle production. We show that our results are in an excellent agreement with the low-p(T) data from 2.76 TeV and 5.02 TeV Pb+Pb collisions at the LHC as well as with the data from the 200 GeV Au+Au collisions at RHIC. In particular, we study the centrality dependences of hadronic multiplicities, flow coefficients, and various flow correlations. Furthermore, the nuclear mass number dependence of the initial particle production and hydrodynamic evolution can be tested in the 5.44 TeV Xe+Xe collisions at the LHC. To this end, we show our predictions for charged particle multiplicities, and in particular, show how the deformations of the Xe nuclei reflect into the flow coefficients.
  • Antchev, G.; Aspell, P.; Atanassov, I.; Avati, V.; Baechler, J.; Berardi, V.; Berretti, M.; Bossini, E.; Bottigli, U.; Bozzo, M.; Broulim, P.; Burkhardt, H.; Buzzo, A.; Cafagna, F. S.; Campanella, C. E.; Catanesi, M. G.; Csanad, M.; Csorgo, T.; Deile, M.; De Leonardis, F.; D'Orazio, A.; Doubek, M.; Eggert, K.; Eremin, V.; Ferro, F.; Fiergolski, A.; Garcia, F.; Georgiev, V.; Giani, S.; Grzanka, L.; Guaragnella, C.; Hammerbauer, J.; Heino, J.; Karev, A.; Kaspar, J.; Kopal, J.; Kundrat, V.; Lami, S.; Latino, G.; Lauhakangas, R.; Linhart, R.; Lippmaa, E.; Lippmaa, J.; Lokajicek, M. V.; Naaranoja, T.; Oljemark, F.; Orava, R.; Österberg, K.; Saarikko, H.; Welti, J.; TOTEM Collaboration (2016)
    The TOTEM experiment at the CERN LHC has measured elastic proton-proton scattering at the centre-of-mass energy root s = 8 TeV and four-momentum transfers squared, vertical bar t vertical bar, from 6 x 10(-4) to 0.2GeV(2). Near the lower end of the t-interval the differential cross-section is sensitive to the interference between the hadronic and the electromagnetic scattering amplitudes. This article presents the elastic cross-section measurement and the constraints it imposes on the functional forms of the modulus and phase of the hadronic elastic amplitude. The data exclude the traditional Simplified West and Yennie interference formula that requires a constant phase and a purely exponential modulus of the hadronic amplitude. For parametrisations of the hadronic modulus with second-or third-order polynomials in the exponent, the data are compatible with hadronic phase functions giving either central or peripheral behaviour in the impact parameter picture of elastic scattering. In both cases, the.-parameter is found to be 0.12 +/- 0.03. The results for the total hadronic cross-section are sigma(tot) = (102.9 +/- 2.3) mb and (103.0 +/- 2.3) mb for central and peripheral phase formulations, respectively. Both are consistent with previous TOTEM measurements.