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Anonymous (not verified)  A new model for realistic 3D simulations of solar energetic particle events  Nicolas Wijsen  KU Leuven  Nicolas.wijsen@kuleuven.be 
The Sun is a highly dynamical object, producing energetic phenomena like bright solar flares and violent eruptions called coronal mass ejections (CMEs). During these eruptions, the Sun hurls a billionton cloud of charged particles into space. There is a consensus in the Heliophysics community that CMEs play a leading role in governing the SunEarth System (SES) as a consequence of their direct interaction with the space environment near the Earth. As CMEs evolve in the solar corona and interplanetary space, they drive shock waves which act as powerful accelerators of charged particles in the inner solar system. These particles, known as solar energetic particles (SEPs), can strike our planet where they may disrupt satellites and endanger human life in outer space. That is why it is important to understand and predict the everchanging environmental conditions in outer space due to solar storms – the Space Weather. A physicsbased model for predicting shockaccelerated energetic particles requires a realistic inner heliospheric model for the solar wind and the evolution of CMEs. In view of this, Dr. Jens Pomoell (Univ. of Helsinki) recently developed EUHFORIA (‘European heliospheric forecasting information asset’). This numerical model consists of 1) a semiempirical coronal model driven by observations of the photospheric magnetic field and 2) an advanced MHD code from 0.1 au onwards to accurately capture the timedependent threedimensional evolution of the solar wind plasma in the inner heliosphere. For reliable SEP modelling one needs not only a heliospheric model for the solar wind and the evolution of CMEs, but also a particle transport code. The propagation of SEPs in the heliosphere can be described by the socalled focused transport equation. One way to solve this fivedimensional parabolic partial differential equation is by integrating a set of corresponding first order Itô stochastic differential equations. In doing so, one can obtain the SEP distributions in interplanetary space. This talk will consist of three parts. In the first part, we will introduce the solar eruptive events that are thought to be the main accelerators of SEPs. In the next part, we will show how these events can be modelled using the EUHFORIA model. Finally, in the last part of the talk, we will discuss how we can model the transport of SEPs in the heliosphere, once they escaped their acceleration site. 

Anonymous (not verified)  Breaking of Translational Invariance in AdS/CFT  Tomas Andrade  University of Barcelona  tandradew@gmail.com 
Motivated by applications to condensed matter physics, we introduce breaking of translational invariance in the context of AdS/CFT. On the gravity side, this entails constructing black branes solutions which are not homogeneous along the directions parallel to the brane. We discuss some applications such as the presence of holographic phonons and the appearance of metalinsulator transitions. 

Anonymous (not verified)  Corecrust transition and crustal properties in neutron stars  Claudia Gonzalez Boquera  University of Barcelona, ICCUB  claugb@fqa.ub.edu 
An accurate determination of the corecrust transition is necessary in the modelling of neutron stars for astrophysical purposes. The properties of the corecrust transition are intimately related to the isospin dependence of the nuclear force at low baryon densities. We obtain the corecrust transition density, asymmetry and pressure by studying the thermodynamical stability of the core. Next, we analyze the correlation of these transition properties with the slope of the symmetry energy associated to the nuclear equation of state. Finally, we integrate the TolmanOppenheimerVolkov equations in order to obtain the relation between the neutron star masses and radii. Knowing the corecrust transition point, we are also able to predict the mass, thickness and moment of inertia of the neutron star crust. 

Anonymous (not verified)  Entanglement and squeezing of one and two impurities in a BEC  M.A. GarcíaMarch  ICFO – Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spai  garciamarchma@gmail.com  Quantum Brownian motion represents a paradigmatic model of complex quantum system. It describes the dynamics of a quantum particle coupled to a bath made up by a huge number of harmonic oscillators. We employ such a model to investigate the physics of one impurity and two distinguishable impurities embedded in a BoseEinstein condensate (BEC). The case of one particle resembles that of the Bose polaron and has been recently realized in experiments. In an open quantum system context the impurity plays the role of the Brownian particle and the bath is constituted by the Bogoliubov excitations of the condensate. We show that the motion of the impurity is described by means of a Langevin quantum equation, with a time nonlocal damping, i.e. carrying a certain amount of memory effects. We solve this stochastic equation for the case in which the impurity is trapped and the BEC is homogeneous. We find genuine position squeezing, i.e. the impurity position variance takes values lower than that imposed by the Heisenberg principle. This effect occurs at low temperatures and is enhanced by the strength of the interactions between the impurity and the BEC. We find the regimes of experimentally realistic parameters in which the model is valid and these effects can be observed. We also study a system of two distinguishable impurities in independent traps embedded in a BEC. We evaluate first how the impurity position variance is affected by the presence of the second impurity. We discuss the entanglement between the two impurities that occurs as a consequence of their independent interaction with the BEC. We detail how this entanglement depends on the distance between their traps, interactions, temperature, trapping frequency etc.  
Anonymous (not verified)  GGD 27 MM1: is it an archetype of an accretion disk around a massive YSO?  Nacho Añez  Institut de Ciències de l'Espai  anyez@ice.csic.es 
The massive star forming region GGD27(IRAS 181622048) is located at a distance of 1.7Kpc. It shows the spectacular and highly collimated radio jet known, HH 808180N, with is powered by a massive (early Btype) protostar. We have found for first time evidences of the presence of an accretion disk surrounding the massive protostar, through (sub)millimetre highangular resolution interferometric observations. HH8081 represents a unique case showing that highmass protostar form through an accretion disk. We modeled accretion disk around massive protostar GGD27 MM1 using the irradiated Alphaacretion disk models with dust settling developed by D’Alession et al. 2006 and updated latter in Osorio et al 2016. In this model the temperature and density structure is calculated selfconsistently and the main heating sources are stellar irradiation and viscous dissipation. By comparing the models with high angular resolution observation at 1.1 mm with ALMA we find a very massive disk, what could mean that relationship between stellar and disk mass is different in massive stars. We found significant substructure in the disk. Here, we compare these substructures with the ones found in low mass disks. 

Anonymous (not verified)  Gravitational waves and the nature of spacetime  Gustavo E. Romero  IAR, CONICET  gustavo.esteban.romero@gmail.com  Gravitational waves are a natural prediction of General Relativity. The direct detection of these waves has been a major confirmation that the theory can make accurate predictions in the strong gravity regime. In this talk I will review some of the implications of this discovery for the hypothesis that spacetime is a real entity.  
Anonymous (not verified)  Massloading and nonthermal emission from AGN jets interacting with stellar populations  Núria TorresAlbà  Universitat de Barcelona (ICCUB)  ntorres@fqa.ub.edu 
Supermassive blackholes, present in the innermost regions of galaxies, may accrete the material surrounding them, becoming AGN. Some AGN produce jets, which propagate through the complex environment characteristic of the central regions of the host galaxy. This may lead to the jet interacting with a variety of obstacles; including stars, gas and dense clouds. These interactions may affect the jet dynamically, massloading and even decelerating it. In addition, when the jet collides with the obstacles, a shock is formed in which particles can be accelerated to relativistic speeds, emitting nonthermal highenergy radiation, potentially detectable for nearby sources. 

Anonymous (not verified)  Open Clusters in the Milky Way with Gaia  Tristan CantatGaudin  ICCUB  tcantat@fqa.ub.edu  Open Clusters are convenient tracers of the properties and structure of the Milky Way, because their ages and distances can be estimated more easily than individual stars. The upcoming second data release of the Gaia mission will provide data of unprecedented quality for more than a billion stars, enabling us to better characterise stellar clusters and to discover new ones, providing more insight on the history and structure of our Galaxy.  
Anonymous (not verified)  Pealing off layers of data contamination when measuring the 3D galaxy power spectrum  Benedict Kalus  ICCUB  benedict.kalus@icc.ub.edu 
I consider techniques to remove contaminants when calculating the 3D galaxy power spectrum. The commonly used naïve template subtraction technique estimates the power spectrum quickly but in a biased way. The mode deprojection scheme is designed to give an unbiased power spectrum, but it requires huge costly matrix operations. Prior to normalisation, template subtraction and mode deprojection yield identical results. I, therefore, argue that one can remove contaminants from the 3D galaxy power spectrum using template subtraction, and then remove the bias either using the normalisation of the quadratic maximum likelihood (QML) estimator as one would do for mode deprojection, or to use a new and computationally cheaper method that is an extension to the FKP estimator and also debases the power spectrum estimate, but slightly increases the error bars by not weighting each mode optimally. However, the increase of the error is small in the test cases that we analyse and is less severe than many other suboptimal assumptions commonly employed. I show how this can be applied to the systematic contaminants in BOSS galaxy data. 

Anonymous (not verified)  Primordial Black Holes in Cosmology  Nicola Bellomo  ICCUB  nicola.bellomo@icc.ub.edu 
The model in which Primordial Black Holes (PBHs) constitute a nonnegligible fraction of the dark matter has (re)gained popularity after the first detections of binary black hole mergers. Most of the observational constraints to date have been derived assuming a single mass for all the PBHs, although some more recent works tried to generalize constraints to the case of extended mass distributions (EMD). In this talk we present a general methodology to obtain constraints for any PBHs EMD and any observables in the desired mass range, starting from those obtained for a monochromatic distribution. We apply this methodology to the study of PBHs effects on the cosmic microwave background in order to put constraints on the fraction of dark matter in PBHs, not only for monochromatic PBH mass distributions but also for popular EMD. Finally we present a way to discriminate if BHs progenitors has primordial or stellar origin by using galaxy surveys. 

Anonymous (not verified)  Prova  Ariadna  ICCUB  ariadna@icc.ub.edu  abstract  
Anonymous (not verified)  prova esther  esther  ICCUB  estpallgui@icc.ub.edu  Hola que tal  
Anonymous (not verified)  Supercomputation applied to Nuclear Physics  Assumpta Parreño  Universitat de Barcelona  assum@fqa.ub.edu 
The dynamics of matter in high energy processes can be studied by using the analytic techniques of quantum field theory. Unfortunately, the complicated quarkgluon dynamics precludes the analytic calculation of lowenergy nuclear reactions, as well as the nuclear structure, directly from the underlying theory of the strong interaction, QCD. During this talk, I will explain how we use supercomputers to calculate strong interaction processes relevant for nuclear physics. I will describe the numerical technique of Lattice QCD, which uses a fourdimensional lattice containing as degrees of freedom the basic building blocks of matter, quarks and gluons, and I will update you on our recent achievements in the field. 

Anonymous (not verified)  TBD  Lluis Mas Ribas  University of Oslo  lluismasribas@gmail.com  TBD  
Anonymous (not verified)  The Connection Between Galaxies and the Intergalactic Medium  Lluis Mas Ribas  University of Oslo  lluismasribas@gmail.com  The evolution of galaxies and the largescale intergalactic medium go hand in hand due to their interaction, which takes place in a region around galaxies called circumgalactic medium. I will present new approaches for probing this region, and how we can extract valuable information from it to reveal some cosmic properties across the history of our Universe.  
Anonymous (not verified)  Type Ia Supernovae: The Search for the Progenitors  Carles Badenes  University of Pittsburgh / ICCUB  badenes@pitt.edu  Type Ia Supernovae are still the best standard candles for the measurement of cosmological distances, but the precise nature of their stellar progenitors remains a mystery. While we are reasonably sure that the exploding star is a white dwarf composed of carbon and oxygen, the mechanism by which this star becomes unstable and explodes has never been established. I will review the current observational evidence on Type Ia SN progenitors, the challenges in this field, and a few recent advances.  
Anonymous (not verified)  Winds and Jets from the Lighthouse Nebula  Pol Bordas  ICCUB  pbordas@fqa.ub.edu  The Lighthouse Nebula is powered by an ultrafast runaway pulsar, IGR J110146103, which is traveling through the interstellar medium at a velocity greater than 1000 km/s. Deep observations of the Nebula with the Chandra satellite have revealed the presence of jetlike structures extending for more than 10 psc, becoming the longest jets ever seen in the Galaxy. A classical jet scenario cannot account however for the observed unbending of these linear structures, nor for its spectral properties. In this talk, I will review the observational data available on the source and the different scenarios proposed to explain its morphology, including the escape of highenergy particles from the pulsar bowshock and their diffusion into the interstellar magnetic field. 