XIII International Workshop on Hadron Physics - XIII Hadron Physics

22 Mar 2015, 15:00 → 27 Mar 2015, 18:30 Brazil/East

Hotel do Bosque

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The XIII International Workshop on Hadron Physics, XIII Hadron Physics, is intended for graduate students, postdocs and researchers in Hadronic Physics, High Energy Physics, Astrophysics and Effective Field Theories, who wish to improve their theoretical background, learn about recent experimental results and develop collaboration projects.

The series Hadron Physics, in activity since 1988, has the format of an advanced school and has the objective to introduce, in a series of pedagogical lectures, new lines of research in Strong Interaction Physics, mainly concerned with QCD. It envisages also to stimulate collaborations in international level.

Sponsors:

• CAPES, CNPq, FAPERJ, FAPESP, IUPAP

Sunday 22 March

15:00 Arrival, Registration and Display of Posters

18:00 Welcome cocktail

19:30 Dinner

Monday 23 March

08:30 Opening

Roberts: I

Convener: Prof. Gastão Krein (UNESP)

1 Primer on continuum QCD

Primer on continuum QCD

Speaker: Dr Craig Roberts (Argonne National Laboratory)

Slides Roberts1.pdf Roberts1.pptx

10:00 Coffee break & Posters

Aarts: I

Convener: Prof. Gastão Krein (UNESP)

2 Lattice QCD at nonzero baryon number

Lattice QCD at nonzero baryon number

Speaker: Prof. Gert Aarts (Swansea University)

Slides aarts1.pdf

Steiner: I

Convener: Prof. Gastão Krein (UNESP)

3 The EOS of dense matter and neutron star structure

The EOS of dense matter and neutron star structure

Speaker: Prof. Andrew Steiner (UTK/ORNL)

Slides steiner1.pdf

12:30 Lunch

Lattice QCD - methods and results

Convener: Prof. Ricardo Farias (Federal University of Santa Maria)

4 Gluon correlations and the deconfinement phase transition

We investigate the critical behavior of electric and magnetic gluon propagators around the deconfinement phase transition for SU(2) gauge theory on the lattice. We test the critical properties of these correlation functions and extract screening masses from their behavior.

Speaker: Prof. Tereza Mendes (University of São Paulo)

Slides tereza_mendes.pdf

Hadronic structure - reactions, production and decays

Convener: Prof. Ricardo Farias (Federal University of Santa Maria)

5 $X(3872)$ production in high energy collisions

We present a short review of the theoretical and experimental status of $X(3872)$ production in high energy proton-proton and nucleus-nucleus collisions at the LHC. We then discuss the interaction of the $X(3872)$ with light mesons in a hadron gas.

Speaker: Prof. Fernando Navarra (USP)

Slides fernando_navarra.pps

6 Production of the Y(4260) state in B meson decay

We calculate the branching ratio for the production of the meson $Y(4260)$ in the decay $B^- \to Y(4260)K^-$. We use QCD sum rules approach and we consider the $Y(4260)$ to be a mixture between charmonium and exotic tetraquark, $[\bar{c}\bar{q}][qc]$, states with $J^{PC}=1^{--}$. Using the value of the mixing angle determined previously as: $\theta=(53.0\pm0.5)^\circ$, we get the branching ratio $\mathcal{B}(B\to Y(4260)K)=(1.34\pm0.47)\times10^{-6}$, which allows us to estimate an interval on the branching fraction $3.0 \times 10^{-8} < {\mathcal B}_{_Y} < 1.8 \times 10^{-6}$ in agreement with the experimental upper limit reported by Babar Collaboration.

Speaker: Dr Raphael M. Albuquerque (University of São Paulo)

17:00 Coffee break & Posters

Hadronic structure - reactions, production and decays

Convener: Prof. Ricardo Farias (Federal University of Santa Maria)

7 Hadronic states with both open charm and bottom in effective field theory

We perform a field-theoretical study of possible deuteron-like molecules with both open charm and bottom, using the Heavy-Meson Effective Theory. In this approach, we analyze the parameter space of the coupling constants and discuss the formation of loosely-bound $D^{(*)} B^{(*)} $-states. We estimate their masses and other properties.

Speaker: Prof. Luciano Abreu (UFBA)

8 Study of pseudoscalar mesons ($\pi^+$, $K^+$) with a symmetric vertex in the light front formalism

In this study, we investigate the electromagnetic form factors, $F^{em}_{X^{0^-}}$, decay constants, $f_{X^{0^-}}$, and charge radii, $\langle r_{X^{0^-}}\rangle$, where $X^{0^-}=\pi^+\text{ or }K^+$, for pion and kaon within the frame work of light-front field theory formalism using symmetric vertex function as a quark-meson interaction vertex. The above mentioned observables are evaluated for the plus component of the electromagnetic current, $J^+$, in the Breit frame while, both, the valance and the non-valance contributions are taken into account. We also study the sensitivity of $F^{em}_{X^{0^-}}$, $f_{X^{0^-}}$ and $\langle r_{X^{0^-}}\rangle$ on the model's parameters, namely, quark masses, $m_u=m_d$, $m_{\bar s}$, and on the regulator mass, $m_R$. It is found that, after fine tuning of regulator mass i.e. $m_R=0.6$ GeV, the model is suitable to fit the experimental values of $f_{X^{0^-}}$ and $\langle r_{X^{0^-}}\rangle$ within the theoretical uncertainties, both, for pion and kaon.

Speaker: Dr Ishtiaq Ahmed (UNICSUL)

Slides ishtiaq_ahmed.pdf

9 A covariant model for the negative parity resonances of the nucleon

One of the challenges of the modern physics is the description of the internal structure of the baryons and mesons. The electromagnetic structure of the nucleon $N$ and the nucleon resonances $N^\ast$ can be accessed through the $\gamma^\ast N \to N^\ast$ reactions, which deppend of the (photon) transfer momentum squared $Q^2$ [1--4]. The data associated with those transitions are represented in terms of helicity amplitudes and have been collected in the recent years at Jefferson Lab, with increasing $Q^2$. The new data demands the development of theoretical models based in the underlying structure of quarks and mesons states [3,4]. Those models can be also very useful to predict the results of the future Jlab--12 GeV upgrade, particularly for resonances in the second and third resonance region (energy $W =1400$--$1750$ GeV) [4]. In that region there are several resonances $N^\ast$ from the supermultiplet $[70,1^-]$ of $SU(6)\otimes O(3)$, characterized by a negative parity [5]. According with the single quark transition model, when the electromagnetic interaction is the result of the photon coupling with just one quark, the helicity amplitudes of the $[70,1^-]$ members depend only of three independent functions of $Q^2$: $A,B$ and $C$ [5,6]. In this work we use the covariant spectator quark model [4,6,7] developed for the $\gamma^\ast N \to N^\ast (1520)$ and $\gamma^\ast N \to N^\ast (1535)$ transitions [8], also members of $[70,1^-]$, to calculate those functions. With the knowledge of the functions $A,B$, and $C$ we predict the helicity amplitudes for the transitions $\gamma^\ast N \to N^\ast(1650)$, $\gamma^\ast N \to N^\ast(1700)$, $\gamma^\ast N \to \Delta(1620)$, and $\gamma^\ast N \to \Delta(1700)$ [6]. To facilitate the comparison with future experimental data at high $Q^2$, we provide also simple parametrizations of the amplitudes $A_{1/2}$ and $A_{3/2}$ for the different transitions, compatible with the expected falloff at high $Q^2$ [6]. [1] I.G. Aznauryan et al. [CLAS Collaboration], Phys. Rev. C 80, 055203 (2009); V.I. Mokeev et al. [CLAS Collaboration], Phys. Rev. C 86, 035203 (2012). [2] L. Tiator, D. Drechsel, S.S. Kamalov and M.Vanderhaeghen, Eur. Phys. J. ST 198, 141 (2011). [3] I.G. Aznauryan and V.D. Burkert, Prog. Part. Nucl. Phys. 67, 1 (2012). [4] I.G. Aznauryan et al. Int. J. Mod. Phys. E 22, 1330015 (2013). [5] V. D. Burkert, R. De Vita, M. Battaglieri, M. Ripani and V. Mokeev, Phys. Rev. C 67, 035204 (2003). [6] G. Ramalho, Phys. Rev. D 90, 033010 (2014). [7] F. Gross, G. Ramalho and M.T.~Peña, Phys. Rev. C 77, 015202 (2008); Phys. Rev. D 85, 093005 (2012). [8] G. Ramalho and M.T. Peña, Phys. Rev. D 89, 094016 (2014); Phys. Rev. D 84, 033007 (2011); G. Ramalho and K. Tsushima, Phys. Rev. D 84, 051301 (2011).

Speaker: Dr Gilberto Ramalho (UFRN)

Strong and electroweak interactions in the standard model

Convener: Prof. Ricardo Farias (Federal University of Santa Maria)

10 Hadronic tau decays in resonance chiral theory

Tau decays are analyzed within the framework of resonance chiral theory. This is an extension of chiral perturbation theory in which resonances are incorporated as dynamical states in the Lagrangian, making use of both chiral symmetry and large N_C considerations. It is seen that after imposing asymptotic QCD constraints, a few effective coupling constants need to be fitted from experiment in order to describe the spectral functions for various decay channels.

Speaker: Prof. Daniel Gomez Dumm (UNLP)

Slides daniel_gomez_dumm.pdf daniel_gomez_dumm.ppt

19:30 Dinner

Tuesday 24 March

Schmidt: I

Convener: Prof. Sergio Duarte (CBPF)

11 An overview about the High Luminosity upgrade of the LHC and the detector upgrades

An overview about the of High Luminosity upgrade of the LHC and the detector upgrades

Speaker: Dr Burkhard Schmidt (CERN)

Slides schmidt1.pdf schmidt1.pptx

10:00 Coffee break & Posters

Roberts: II

Convener: Prof. Sergio Duarte (CBPF)

12 The ins and outs of mesons

The ins and outs of mesons

Speaker: Dr Craig Roberts (Argonne National Laboratory)

Slides Roberts2.pdf Roberts2.pptx

Aarts: II

Convener: Prof. Sergio Duarte (CBPF)

13 The QCD phase diagram at real and imaginary chemical potential

The QCD phase diagram at real and imaginary chemical potential

Speaker: Prof. Gert Aarts (Swansea University)

Slides aarts2.pdf

12:30 Lunch (and Conference photo)

Field theoretical approaches to QCD

Convener: Prof. Arlene Cristina Aguilar (UNICAMP)

14 Decay constants of the pion and its excitations in holographic QCD

There is a remarkable prediction of QCD that the leptonic decay constants of the excited states of the pion are dramatically suppressed relative to that of the ground-state pion - in the chiral limit, the decay constants of the excited pions are exactly zero. Although within a quark model perspective a suppression of a leptonic decay constant for excited states is expected, as it is proportional to the wave-function at the origin, there is, however, no a priori reason, within such a perspective, for the dramatic suppression predicted by QCD. Lattice computations give conflicting results. In the present talk we present results of a recent study of the structure of excited pions within a chiral holographic QCD model; we present results on the leptonic decay constants of pion's excited states and present new predictions concerning their quark mass dependence. Comparisons are made with corresponding results obtained in light-front holography.

Speaker: Prof. Gastão Krein (UNESP)

Slides gastão_krein.pdf

15 Hadrons in holographic AdS/QCD models

We review some hadron properties obtained from holographic AdS/QCD models.

Speaker: Prof. Henrique Boschi (UFRJ)

Slides henrique_boschi.pdf

16 Dynamical AdS/QCD model for light-mesons and baryons

We construct a Dynamical AdS/QCD model for Light-Mesons and Baryons. The model is a solution of five-dimensional Einstein-dilaton equations that encodes essential features of holographic QCD backgrounds dynamically. Our solution for the gravity background corresponds to a deformed Anti-de Sitter metric at the relevant QCD scale. In this unified model we obtained Regge Trajectories for Light-Mesons and Baryons.

Speaker: Prof. Wayne de Paula (ITA)

Slides wayne_de_paula.pdf wayne_de_paula.ppt

17:00 Coffee break & Posters

Strong and electroweak interactions in the standard model

Convener: Prof. Arlene Cristina Aguilar (UNICAMP)

17 Direct CP Violation in charmless three-body decays of B mesons

Charmless three-body decays of $B^+$ mesons are an excellent laboratory for direct CP violation (CPV) studies. While in two-body decays one measures a single number - the CP asymmetry in the partial decay rates -, in three-body decays the distribution of CP asymmetries across the two-dimensional phase space brings additional information on the underlying mechanisms. Recently the LHCb collaboration performed a study of CP asymmetries in the Dalitz plot of the decays $B^+ \to \pi^+\pi^-\pi^+$, $B^+ \to K^+\pi^-\pi^+$, $B^+ \to K^+\pi^-K^+$, and $B^+ \to K^+K^-K^+$. CP asymmetries as large as 80% were found in regions of the Dalitz plots. The distribution of the CP asymmetry across the phase space exhibit a complex pattern, which may be a consequence of the interplay between the weak and strong phases. In this talk these results will be presented and a possible interpretation will be discussed.

Speaker: Prof. Alberto Correa Dos Reis (CBPF - Brazilian Center for Physics Research (BR))

Slides alberto_correa_dos_reis.pdf

18 Charmless three-body B-decays: final state interaction and CP violation

We will discuss recent results for the formulation of charged three-body $B$ decays in charmless channels, like $KKK$, $\pi\pi$, $KK\pi$, and $\pi\pi\pi$, introducing the final state interaction in the decay amplitude with relation to the CPT constraint, while CP violation is allowed. We consider the s-wave interaction between the mesons, coupling between different decay channels and a resonance. The p-wave interaction in the resonant states, as the formation of the $\rho$-meson in the $\pi\pi$ channel is considered within the general formulation of the three-body decay channel. In this case the CP violation has contributions from the interference between different mechanisms, like e.g. interference from s and p-wave amplitudes. In particular, we will present preliminary results for the CP asymmetry with dependence on $\cos(\theta)$ in charmless charged channels, as revealed by the recent data from LHCb. We will also discuss briefly a relativistic three-body formalism for the final sate interaction based on the projection of the inhomogeneous Bethe-Salpeter equation onto the light-front with application to the D decay in $K\pi\pi$ channel.

Speaker: Prof. Tobias Frederico (Instituto Tecnologico de Aeronautica)

Slides tobias_frederico.pdf

19 Opening angle as an evolution variable for parton distributions

We consider the opening angle as an evolution variable for parton distributions. This allow us to take into account both DGLAP and BFKL leading logarithms and arrive at a single evolution equation, useful for Monte Carlo simulations. Most current global analysis only take into account DGLAP effects, therefore the use of our evolution equation should be particularly important at small *x*.

Speaker: Prof. Emmanuel de Oliveira (UFSC)

Slides emmanuel_de_oliveira.pdf

20 The role of the Unruh effect in multi-particle processes

We discuss the relevance of the Unruh effect in multiparticle processes. We review the cases where it is nothing more than an effective description of "conventional" multi-particle processes describeable, in the inertial frame, through standard scattering theory, and discuss cases where this equivalency breaks down. We suggest that an experimental investigation of this issue, achievable in the foreseeable future via strong laser physics, is a promising avenue to investigate fundamental physics, using beta decays as an example.

Speaker: Prof. Giorgio Torrieri (JW Goethe Universitat, Frankfurt)

Slides giorgio_torrieri.pdf

19:30 Dinner

Colloquium

Convener: Prof. Erasmo Ferreira (Universidade Federal do Rio de Janeiro)

21 Modelling hadronic matter

Hadron physics stands somewhere in the diffuse intersection between nuclear and particle physics and relies largely on the use of models. Historically, around 1930, the first nuclear physics models known as the liquid drop model and the semi-empirical mass formula established the grounds for the study of nuclei properties and nuclear structure. These two models are parameter dependent. Nowadays, around 500 hundred non-relativistic (Skyrme-type) and relativistic models are available and largely used and the vast majority are parameter dependent models. I will discuss some of the shortcomings of using non-relativistic models and the advantages of using relativistic ones when applying them to describe hadronic matter. I will also show possible applications of relativistic models to physical situations that cover part of the QCD phase diagram: I will mention how the description of compact objects can be done, how heavy-ion collisions can be investigated, how parameter dependent the critical end point can be (if it really exists) and show the relation between liquid-gas phase transitions and the pasta phase. Finally, hadronic matter subject to strong magnetic fields will be shortly discussed.

Speaker: Prof. Debora Menezes (UFSC)

Slides debora_menezes.pdf

Wednesday 25 March

Steiner: II

Convener: Prof. Tobias Frederico (Instituto Tecnologico de Aeronautica)

22 Transport properties in dense matter and neutron star evolution

Transport properties in dense matter and neutron star evolution

Speaker: Prof. Andrew Steiner (UTK/ORNL)

Slides steiner2.pdf

10:00 Coffee break & Posters

Schmidt: II

Convener: Prof. Tobias Frederico (Instituto Tecnologico de Aeronautica)

23 The physics reach and the performance requirements for the experiments

The physics reach and the performance requirements for the experiments

Speaker: Dr Burkhard Schmidt (CERN)

Slides schmidt2.pdf schmidt2.pptx

Roberts: III

Convener: Prof. Tobias Frederico (Instituto Tecnologico de Aeronautica)

24 Baryons, as they really are

Baryons, as they really are

Speaker: Dr Craig Roberts (Argonne National Laboratory)

Slides Roberts3.pdf Roberts3.pptx

12:30 Lunch

15:30 Free afternoon

19:30 Dinner

21:00 Luau

Thursday 26 March

Aarts: III

Convener: Prof. Daniel Gomez Dumm (UNLP)

25 Complex Langevin dynamics as a solution to the sign problem

Complex Langevin dynamics as a solution to the sign problem

Speaker: Prof. Gert Aarts (Swansea University)

Slides aarts3.pdf

10:00 Coffee break & Posters

Field theoretical approaches to QCD

Convener: Prof. Daniel Gomez Dumm (UNLP)

26 Non-perturbative BRST breaking, confinement and Gribov copies

In this seminar, we investigate the role of a non-perturbative breaking of the BRST invariance in the infrared regime of non-Abelian gauge theories and its possible relation to confinement. This breaking naturally arises from the procedure of quantization of Landau-gauge Yang-Mills theories that takes into account the presence of Gribov copies. The resulting non-perturbative framework -- the Refined Gribov-Zwanziger theory -- is consistent with different lattice data. One can also construct direct signatures of BRST breaking in the matter sector of confining Yang-Mills theories that are in principle accessible via lattice simulations, allowing for a new non-perturbative model of matter confinement that can be treated (semi-)analytically.

Speaker: Dr Leticia Palhares (UERJ)

Slides letícia_palhares.pdf

27 Thermodynamics of an exactly solvable confining quark model

The grand partition function of a model of confined quarks is exactly calculated at arbitrary temperatures and quark chemical potentials. The model is inspired by a softly BRST-broken version of QCD and possesses a quark mass function compatible with nonperturbative analyses of lattice simulations and Dyson-Schwinger equations. Even though the model is defined at tree level, we show that it produces a non-trivial and stable thermodynamic behaviour at any temperature or chemical potential. Results for the pressure, the entropy and the trace anomaly as a function of the temperature are qualitatively compatible with the effect of non-perturbative interactions as observed in lattice simulations. The finite density thermodynamics is also shown to contain non-trivial features, being far away from an ideal gas picture.

Speaker: Prof. Bruno Mintz (UERJ)

Slides bruno_mintz.pdf

28 Hydrodynamic transport coefficients for the non-conformal quark-gluon plasma from holography

We obtain holographic formulas for the transport coefficients $\kappa$ and $\tau_\pi$ present in the second-order derivative expansion of relativistic hydrodynamics in curved spacetime associated with a non-conformal strongly coupled plasma described holographically by an Einstein+Scalar action in the bulk. We compute these coefficients as functions of the temperature in a bottom-up non-conformal model that is tuned to reproduce (2+1)-flavor lattice QCD thermodynamics at zero baryon chemical potential. We directly compute, besides the speed of sound, 6 other transport coefficients that appear at second-order in the derivative expansion. We also give estimates for the temperature dependence of 11 other transport coefficients taking into account the simplest contributions from non-conformal effects that appear near the QCD crossover phase transition. Using these results, we construct an Israel-Stewart-like theory in flat spacetime containing 13 of these 17 transport coefficients that should be suitable for phenomenological applications in the context of numerical hydrodynamic simulations of the strongly-coupled, non-conformal quark-gluon plasma.

Speaker: Dr Rômulo Rougemont (USP)

Slides romulo_rougemont.pdf

Hadronic and quark matter - applications in astrophysics

Convener: Prof. Daniel Gomez Dumm (UNLP)

29 Why "black widow" pulsar systems are important for the quest of neutron star maximum mass

Relativistic binary systems showing the ablation of the donor star by pulsar winds have been discovered in 1988 and studied recently using FermiLat and other facilities. We discuss in this presentation the evolution of the "black widow" systems, showing that theoretical tracks reveal i) the importance of illumination feedback of X rays onto the donor star, ii) a long (several Gyr) overall timescale to arrive to the observed orbital period-donor mass plane iii) their parenthood with the younger "redback" binary systems; and iv) the large mass transfer occurred along the evolution, which justifies the recent claims of very large masses ($> 2 M_{\odot}$) of the neutron stars as measured in at least three cases. We show how these features impact the supranuclear equation of state and limit compositional possibilities.

Speaker: Prof. Jorge Horvath (IAG-USP)

Slides jorge_horvath.pdf jorge_horvath.pptx

12:30 Lunch

Hadronic and quark matter - applications in astrophysics

Convener: Prof. Jorge Horvath (IAG-USP)

30 Ultra high energy cosmic rays: the highest energy frontier

Ultra-high energy cosmic rays (UHECR) are the highest energy messengers of the present universe, with energies up to $10^{20}$ eV. Studies of astrophysical particles (hadrons, neutrinos and photons) at their highest observed energies have implications for fundamental physics as well as astrophysics. The primary particles interacts in the atmosphere and generates an extensive air shower. Analysis of those showers enables one not only to estimate the energy, direction and most probable mass of the primary cosmic particles, but also to obtain information about the properties of their hadronic interactions at an energy more than one order of magnitude above that accessible with the current highest energy human-made accelerator. In this contribution we will review the state-of-the-art in UHECRs detection. We will present the leading experiments and discuss the cosmic ray energy spectrum, searches for directional anisotropy, studies of mass composition, the determination of the number of shower muons (which is sensitive to the shower hadronic interactions), and limits on the fluxes of primary photons and neutrinos.

Speaker: Prof. João de Mello Neto (Federal University of Rio de Janeiro)

Slides joão_de_mello_neto.pdf

Relativistic heavy-ion reactions - new data, analyses and models

Convener: Prof. Jorge Horvath (IAG-USP)

31 Heavy Ion physics at LHCb

The LHCb collaboration studied the production of J/Psi and Upsilon mesons in proton-lead collisions at a proton nucleon centre-of-mass energy of 5 TeV. The measurements have been used to determine the nuclear modification factor and to compare the results with theoretical predictions. A measurement of Z boson production in proton-lead collisions is presented as well. The analyses are based on a data sample corresponding to an integrated luminosity of about 1/nb.

Speaker: Prof. Murilo Santana Rangel (Univ. Federal do Rio de Janeiro (BR))

Slides murilo_rangel.pdf

17:00 Coffee break & Posters

Relativistic heavy-ion reactions - new data, analyses and models

Convener: Prof. Jorge Horvath (IAG-USP)

32 Prompt photon measurements with ALICE experiment for quark-gluon plasma study

The ALICE experiment is mainly devoted to the study of quark-gluon plasma (QGP) expected to be created in heavy ion collisions. Since electromagnetic probes do not interact strongly whith the QGP, direct photons are reliable witnesses of the energy of the initial hard process. This property allows one to investigate, e.g., hadrons energy loss mechanisms in the medium via gammajet studies. The measurement of direct photons production is also interesting in p-p collisions, as it provides a test of the QCD cross section as well as it constrains the proton parton distribution function (PDF). The ALICE Electromagnetic Calorimeter (EMCal) efficiently detects photons up to pt=100 GeV/c. To identify direct photons, a combination of techniques including (electromagnetic) shower shape analysis and isolation cut has been used. These methods are efficient in getting rid of decay photons background, dominant in p-p collision at the TeV energy scale. An overview of ALICE prompt photon measurements in pp and Pb-Pb collisions will be presented. Finally the complementarity of ALICE and the other experiments (CMS and ATLAS) will be highlighted.

Speaker: Dr Alexis Jean-Michel Mas (Universidade de Sao Paulo (BR))

Slides HadronPhysics_A.Mas_v3.pdf

33 Inclusive photon production at forward rapidities in pp collisions at LHC energies with the ALICE experiment

Measurements of multiplicity and pseudorapidity distributions of particles produced in pp collisions are important for the study of particle production mechanisms and to obtain baseline distributions to be compared with those from heavy-ion collisions. The inclusive photon measurements (dominated by $\pi^{0}$ decays) are complementary to the charged particle measurements. The present work focuses on the forward rapidity region with comparisons to different models such as PYTHIA and PHOJET. We report the measurements of multiplicity and pseudorapidity distributions of inclusive photons using the ALICE Photon Multiplicity Detector (PMD) at forward rapidities (2.3$<\eta<$3.9) in pp collisions at $\sqrt{s}$ = 0.9, 2.76 and 7 TeV. It is observed that the photon multiplicity distributions are well described by negative binomial distributions (NBD). Multiplicity distributions are studied in terms of KNO variables for each energy. It is shown that the increase in the average photon multiplicity as a function of beam energy is compatible with both a logarithmic and power law dependence. The results are compared to different model predictions. These models reproduce experimental results at lower energy while they are not accurate at higher energies.

Speaker: Dr Sudipan De (USP)

Slides sudipan_de.pdf sudipan_de.ppt

18:30 Meeting of the Brazilian community

Choice of the Organizing Committee of the XIV Hadron Physics

19:30 Poster winners

20:00 Lunch

Friday 27 March

Hadronic and quark matter - applications in astrophysics

Convener: Prof. Luciano Abreu (UFBA (Federal University of Bahia))

34 Pasta phases in core-collapse supernova matter

The pasta phase in core-collapse supernova matter (finite temperatures and fixed pro- ton fractions) is studied within relativistic mean field models. Three different calculations are used for comparison, the Thomas-Fermi (TF), the Coexistence Phase (CP) and the Compressible Liquid Drop (CLD) approximations. The effects of including light clusters in nuclear matter and the densities at which the transitions between pasta configurations and to uniform matter occur are also investigated. The free energy and pressure, in the space of particle number densities and temperatures expected to cover the pasta region, are cal- culated. Finally, a comparison with a finite temperature Skyrme-Hartree-Fock calculation is drawn.

Speaker: Dr Helena Pais (University of Coimbra)

Slides helena_pais.pdf

35 Pasta in QMC

In the present paper we employ the quark-meson coupling model (QMC) to investigate the onset of the pasta phase in nuclear matter under conditions such as those expected in neutron star crusts. Pasta is obtained with fixed proton fractions and for beta equilibrated matter. We probe our results into restrictions imposed on the the values of the density and pressure at the inner edge of the crust, recently achieved by observation, as well as comparing them to the pasta obtained from Walecka-type models.

Speaker: Prof. Alexandre Santos (UFSC)

10:00 Coffee break & Posters

Steiner: III

Convener: Prof. Luciano Abreu (UFBA (Federal University of Bahia))

36 Nuclear structure and the neutron star crust

Nuclear structure and the neutron star crust

Speaker: Prof. Andrew Steiner (UTK/ORNL)

Slides steiner3.pdf

Schmidt: III

Convener: Prof. Luciano Abreu (UFBA (Federal University of Bahia))

37 Challenges and developments in detector technologies, electronics and computing

Challenges and developments in detector technologies, electronics and computing

Speaker: Dr Burkhard Schmidt (CERN)

Slides schmidt3.pdf schmidt3.pptx

12:30 Lunch

14:00 Departure