Results for "Simona Murgia"

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Fermi-LAT Observations of Gamma-Ray Emission Towards the Outer Halo of M31Dec 07 2018The Andromeda Galaxy is the closest spiral galaxy to us and has been the subject of numerous studies. It harbors a massive dark matter (DM) halo which may span up to ~600 kpc across and comprises ~90% of the galaxy's total mass. This halo size translates ... More
Fermi-LAT Observations of Gamma-Ray Emission Towards the Outer Halo of M31Mar 25 2019The Andromeda Galaxy is the closest spiral galaxy to us and has been the subject of numerous studies. It harbors a massive dark matter (DM) halo which may span up to ~600 kpc across and comprises ~90% of the galaxy's total mass. This halo size translates ... More
Search for gamma-ray emission from $p$-wave dark matter annihilation in the Galactic CenterApr 12 2019Indirect searches for dark matter through Standard Model products of its annihilation generally assume a cross-section which is dominated by a term independent of velocity ($s$-wave annihilation). However, in many DM models an $s$-wave annihilation cross-section ... More
Possible detection of gamma rays from Epsilon EridaniOct 09 2018We use the Fermi-LAT gamma-ray observatory to search for gamma-ray emission from four nearby, debris disk-hosting main sequence stars: $\tau$ Ceti, $\epsilon$ Eridani, Fomalhaut, and Vega. For three stars ($\tau$ Ceti, Fomalhaut, and Vega), we establish ... More
Azimuthal and transverse single spin asymmetries in hadronic collisionsOct 01 2010We give a short overview of the phenomenology of azimuthal and transverse single spin asymmetries in (un)polarized high-energy hadronic collisions. We briefly summarize a transverse momentum dependent, generalized parton model approach to these polarization ... More
$^1P_1$ charmonium state decay into $p \bar p$ in QCD models including constituent quark mass correctionsJan 31 1996Jul 16 1996Stimulated by the experimental observation, made by the E760 Collaboration at Fermilab, of the $^1\!P_1$ state of charmonium resonantly formed in $p\,\bar p$ annihilation, we perform a calculation of the decay width for the $^1\!P_1\to p\,\bar p$ process. ... More
Saving the MSSM from the Galactic Center ExcessDec 21 2016The minimal supersymmetric setup offers a comprehensive framework to interpret the Fermi LAT Galactic center excess. Taking into account experimental, theoretical, and astrophysical uncertainties we can identify valid parameter regions linked to different ... More
Observations of High-Energy Gamma-Ray Emission Toward the Galactic Centre with the Fermi Large Area TelescopeJul 16 2015The inner region of the Milky Way is one of the most interesting and complex regions of the gamma-ray sky. The intense interstellar emission and resolved point sources, as well as potential contributions by other sources such as unresolved source populations ... More
Weakly globular Tamsamani N-categories and their rigidificationJul 17 2016Sep 14 2016We introduce a new class of higher categorical structures called weakly globular Tamsamani n-categories. These generalize the Tamsamani-Simpson model of higher categories by using the new paradigm of weak globularity to weaken higher categorical structures. ... More
Chimera states in coupled Kuramoto oscillators with inertiaDec 14 2015The dynamics of two symmetrically coupled populations of rotators is studied for different values of the inertia. The system is characterized by different types of solutions, which all coexist with the fully synchronized state. At small inertia the system ... More
A stability-like theorem for cohomology of pure braid groups of the series A, B and DJul 10 2003Oct 15 2003Consider the ring $R:=\Q[\tau,\tau^{-1}]$ of Laurent polynomials in the variable $\tau$. The Artin's Pure Braid Groups (or Generalized Pure Braid Groups) act over $R,$ where the action of every standard generator is the multiplication by $\tau$. In this ... More
Applications of Asymptotic Riesz Representation TheoremAug 27 2012We review the relation between compact asymptotic spectral measures and certain positive asymptotic morphism on locally compact spaces via asymptotic Riesz representation theorem, as introduced by Martinez and Trout [3]. Applications to this theorem will ... More
Segal-type models of higher categoriesJul 06 2017Higher category theory is an exceedingly active area of research, whose rapid growth has been driven by its penetration into a diverse range of scientific fields. Its influence extends through key mathematical disciplines, notably homotopy theory, algebraic ... More
The development of a fuzzy regulator with an entry and an output in FislabMar 25 2009The present article is a sequel of the article "Fislab the Fuzzy Inference Tool-Box for Scilab" and it represents the practical application of:"The development of the Fuzzy regulator with an input and an output in Fislab". The article contains, besides ... More
Pseudo-functors modelling higher structuresMay 22 2016We introduce a new higher categorical structure called a weakly globular n-fold category. This structure is based on iterated internal categories and on the notion of weak globularity. We identify a suitable class of pseudo-functors whose strictification ... More
Local spectrum of a family of operatorsJul 13 2012Starting from the classic definitions of local resolvent set and spectrum of a linear bounded operator on a Banach space, we introduce the local resolvent set and spectrum, the local space and the single-valued extention property of a family of linear ... More
FISLAB - the Fuzzy Inference Tool-box for SCILABMar 25 2009The present study represents "The Fislab package of programs meant to develop the fuzzy regulators in the Scilab environment" in which we present some general issues, usage requirements and the working mode of the Fislab environment. In the second part ... More
Homotopically discrete higher categorical structuresMay 17 2016We introduce the notion of homotopically discrete n-fold category as an n-fold generalization of a groupoid with no non-trivial loops. We give two equivalent descriptions of this structure: in terms of a Segal-type model and in terms of iterated internal ... More
On the non-balanced property of the category of crossed modules in groupsSep 24 2003An algebraic category $\mathcal{C}$ is called balanced if the cotriple cohomology of any object of $\mathcal{C}$ vanishes in positive dimensions on injective coefficient modules. Important examples of balanced and of non-balanced categories occur in the ... More
On biconservative surfacesApr 15 2017We study in a uniform manner the properties of biconservative surfaces in arbitrary Riemannian manifolds. Biconservative surfaces being characterized by the vanishing of the divergence of a symmetric tensor field $S_2$ of type $(1,1)$, their properties ... More
Weakly globular N-fold categories as a model of weak N-categoriesSep 13 2016We study a new type of higher categorical structure, called weakly globular n-fold category, previously introduced by the author. We show that this structure is a model of weak n-categories by proving that it is suitably equivalent to the Tamsamani-Simpson ... More
Complete biconservative surfaces in $\mathbb{R}^3$ and $\mathbb{S}^3$May 27 2016In this paper we consider the complete biconservative surfaces in Euclidean space $\mathbb{R}^3$ and in the unit Euclidean sphere $\mathbb{S}^3$. Biconservative surfaces in 3-dimensional space forms are characterized by the fact that the gradient of their ... More
Blocking Sets in the complement of hyperplane arrangements in projective spaceFeb 14 2008It is well know that the theory of minimal blocking sets is studied by several author. Another theory which is also studied by a large number of researchers is the theory of hyperplane arrangements. We can remark that the affine space $AG(n,q)$ is the ... More
Spectrum of a family of operatorsJul 10 2012Having as start point the classic definitions of resolvent set and spectrum of a linear bounded operator on a Banach space, we introduce the resolvent set and spectrum of a family of linear bounded operators on a Banach space. In addition, we present ... More
The integer cohomology of toric Weyl arrangementsAug 03 2010Dec 16 2011A referee found an error in the proof of the Theorem 2 that we could not fix. More precisely, the proof of Lemma 2.1 is incorrect. Hence the fact that integer cohomology of complement of toric Weyl arrangements is torsion free is still a conjecture. ----- ... More
Diffuse radio sources in colliding galaxy clusters - Low frequency follow up of the GMRT Radio Halo SurveyFeb 09 2011The knowledge of the origin and statistical properties of diffuse radio emission in galaxy clusters has appreciably improved thanks to the GMRT Radio Halo Survey, a project based on 610 MHz observations of clusters belonging to a statistically complete ... More
Semistrict models of connected 3-types and Tamsamani's weak 3-groupoidsJul 14 2006Homotopy 3-types can be modelled algebraically by Tamsamani's weak 3-groupoids as well as, in the path-connected case, by cat^2-groups. This paper gives a comparison between the two models in the path-connected case. This leads to two different semistrict ... More
Cohomology of Pure Braid Groups of exceptional casesMay 26 2005May 10 2006Consider the ring R:=\Q[\tau,\tau^{-1}] of Laurent polynomials in the variable \tau. The Artin's Pure Braid Groups (or Generalized Pure Braid Groups) act over R, where the action of every standard generator is the multiplication by \tau. In this paper ... More
Semistrict Tamsamani n-groupoids and connected n-typesJan 23 2007Oct 03 2007Tamsamani's weak n-groupoids are known to model n-types. In this paper we show that every Tamsamani weak n-groupoid representing a connected n-type is equivalent in a suitable way to a semistrict one. We obtain this result by comparing Tasmamani's weak ... More
$χ_{c2} \to ρρ$ and the $rho$ polarization in massless perturbative QCD: how to test the distribution amplitudesOct 05 1995We compute the helicity density matrix of $\rho$ vector mesons produced in the two-body decays of polarized $\chi_{c2}$'s in the framework of massless perturbative QCD. The $\chi_{c2}$'s are either exclusively or inclusively produced in $p \, \bar p$ ... More
Spin effects in the fragmentation of a transversely polarized quarkFeb 10 2000Feb 11 2000An azimuthal dependence of pions produced in polarized Deep Inelastic Scattering, gamma^* - p(transv. polarized) -> pion + X, has been recently observed and might be related to the so-called Collins effect. We discuss in details, for a general spin configuration ... More
Single spin asymmetries and vector meson production in DISJul 14 1998We discuss possible measurements and origins of single spin asymmetries in DIS and of some unusual spin properties of vector mesons produced in lepton- nucleon, photon-nucleon and photon-photon interactions. Such effects have already been observed in ... More
Single spin asymmetries in transversely polarized proton(antiproton) - proton inclusive processesAug 26 1998We consider several single spin asymmetries in inclusive, transversely polarized proton(antiproton) - proton processes as higher twist QCD contributions, taking into account spin and intrinsic transverse momentum effects in the quark distribution functions. ... More
$χ_{c2} \to ρρ$ Decay and the $ρ$ Polarization in Inclusive Processes: A Test of Mass EffectsOct 27 1993We compute the helicity density matrix of $\rho$ vector mesons produced in the two-body decays of $\chi_{c2}$'s in the framework of perturbative QCD, allowing for mass corrections. The $\chi_{c2}$'s are inclusively produced in hadronic interactions via ... More
Search for Large Extra Dimensions Using Dielectron and Diphoton Events in $p\bar{p}$ Collisions at $\sqrt{s}=1.8$ TeVMar 17 2006Arkani-Hamed, Dimopoulous, and Dvali have proposed a model of low-scale quantum gravity featuring large extra dimensions. In this model, the exchange of Kaluza-Klein towers of gravitons can enhance the production rate of electron and photon pairs at high ... More
Dark Matter Interpretation of the Fermi-LAT Observation Toward the Galactic CenterDec 17 2016The center of the Milky Way is predicted to be the brightest region of gamma-rays generated by self-annihilating dark matter particles. Excess emission about the Galactic center above predictions made for standard astrophysical processes has been observed ... More
Transverse Momentum Dependent Distributions in Hadronic Collisions: p(transv. polarized) p --> D + X and p(transv. polarized) p --> gamma + XDec 18 2006Our understanding of the transverse spin structure of hadrons might definitely get improved by the information we gather on transverse momentum dependent (TMD) distributions. These new functions could also be crucial for a description of the observed ... More
Parton intrinsic motion: unpolarized cross sections and the Sivers effect in inclusive particle productionDec 21 2004We present a detailed study, performed in the framework of LO perturbative QCD with the inclusion of spin and k_T effects, of unpolarized cross sections for the Drell-Yan process and for inclusive pion and photon production in hadronic collisions, in ... More
The distribution of cycles in breakpoint graphs of signed permutationsApr 17 2011Aug 05 2012Breakpoint graphs are ubiquitous structures in the field of genome rearrangements. Their cycle decomposition has proved useful in computing and bounding many measures of (dis)similarity between genomes, and studying the distribution of those cycles is ... More
Heuristic average-case analysis of the backtrack resolution of random 3-Satisfiability instancesJan 14 2004An analysis of the average-case complexity of solving random 3-Satisfiability (SAT) instances with backtrack algorithms is presented. We first interpret previous rigorous works in a unifying framework based on the statistical physics notions of dynamical ... More
The $\textbf{nbc}$ minimal complex of supersolvable arrangementsMar 19 2015In this paper we give a very natural description of the bijections between the minimal CW-complex homotopy equivalent to the complement of a supersolvable arrangement $\mathcal{A}$, the $\textbf{nbc}$ basis of the Orlik-Solomon algebra associated to $\mathcal{A}$ ... More
Global properties of biconservative surfaces in $\mathbb{R}^3$ and $\mathbb{S}^3$Jan 26 2017Apr 14 2017We survey some recent results on biconservative surfaces in $3$-dimensional space forms $N^3(c)$ with a special emphasis on the $c=0$ and $c=1$ cases. We study the local and global properties of such surfaces, from extrinsic and intrinsic point of view. ... More
Modifications of the Dielectric Properties of Biological Membranes by HeatingApr 28 2004Biological cell suspensions are known to show dielectric dispersions due to the Maxwell-Wagner mechanism. Many examples are summarized in a number of papers by Schwan [7, 9, 10]. By the application of an appropriate analysis to the dielectric dispersion, ... More
Other Classes of Tangent Bundles with General Natural Almost Anti-Hermitian StructuresFeb 17 2010We continue the study of the anti-Hermitian structures of general natural lift type on the tangent bundles. We get the conditions under which these structures are in the eight classes obtained by Ganchev and Borisov. We complete the characterization of ... More
Natural Diagonal Riemannian Almost Product and Para-Hermitian Cotangent BundlesApr 14 2011We obtain the natural diagonal almost product and locally product structures on the total space of the cotangent bundle of a Riemannian manifold. We find the Riemannian almost product (locally product) and the (almost) para-Hermitian cotangent bundles ... More
Two-track categoriesFeb 17 2010We describe a 2-dimensional analogue of track categories, called two-track categories, and show that it can be used to model categories enriched in 2-type mapping spaces. We also define a Baues-Wirsching type cohomology theory for track categories, and ... More
The homotopy type of toric arrangementsSep 19 2010Oct 27 2010A toric arrangement is a finite set of hypersurfaces in a complex torus, every hypersurface being the kernel of a character. In the present paper we build a CW-complex homotopy equivalent to the arrangement complement, with a combinatorial description ... More
Combinatorial polar orderings and recursively orderable arrangementsNov 09 2007Oct 25 2012Polar orderings arose in recent work of Salvetti and the second author on minimal CW-complexes for complexified hyperplane arrangements. We study the combinatorics of these orderings in the classical framework of oriented matroids, and reach thereby a ... More
Topological aspects of the multi-language phases of the Naming Game on community-based networksOct 27 2016The Naming Game is an agent-based model where individuals communicate to name an initially unnamed object. On a large class of networks continual pairwise interactions lead the system to an ultimate consensus state, in which agents converge on a globally ... More
First-principles simulations of glass-formersApr 27 2016In this article we review results of computer simulation of glasses carried out using first principles approaches, notably density functional theory. We start with a brief introduction to this method and compare the pros and cons of this approach with ... More
The impact of baryonic physics on the subhalo mass function and implications for gravitational lensingAug 24 2016We investigate the impact of baryonic physics on the subhalo population by analyzing the results of two recent hydrodynamical simulations (EAGLE and Illustris), which have very similar configuration, but a different model of baryonic physics. We concentrate ... More
Octahedral, dicyclic and special linear solutions of some unsolved Hamilton-Waterloo problemsFeb 29 2016We give a sharply-vertex-transitive solution of each of the nine Hamilton-Waterloo problems left open by Danziger, Quattrocchi and Stevens.
Combinatorial Morse theory and minimality of hyperplane arrangementsMay 21 2007We find an explicit combinatorial gradient vector field on the well known complex S (Salvetti complex) which models the complement to an arrangement of complexified hyperplanes. The argument uses a total ordering on the facets of the stratification of ... More
Phenomenology of single transverse spin asymmetriesNov 30 2000A unified and consistent phenomenological approach to single transverse spin asymmetries in the framework of perturbative QCD, with the inclusion of a new class of spin and k_T dependent distribution and fragmentation functions, is presented. As an example, ... More
Parton intrinsic motion in inclusive particle production: unpolarized cross sections, single spin asymmetries and the Sivers effectAug 06 2004The relevance of intrinsic (or primordial) transverse momentum of partons in the inclusive production of particles at high energy and moderately large p_T has been known for a long time, beginning with Drell-Yan and diphoton processes, and continuing ... More
Azimuthal and Single Spin Asymmetries in Hard Scattering ProcessesDec 28 2007In this article we review the present understanding of azimuthal and single spin asymmetries for inclusive and semi-inclusive particle production in unpolarized and polarized hadronic collisions at high energy and moderately large transverse momentum. ... More
An improved analysis of k_T effects for SSA in hadronic collisionsSep 25 2003The role of intrinsic transverse momentum both in unpolarized and polarized processes is discussed. We consider inclusive cross sections for pion production in hadronic collisions and for Drell-Yan processes. We reanalyze transverse single spin asymmetries ... More
Cross sections and single spin asymmetries in hadronic collisions with intrinsic transverse momentum effectsNov 29 2002The role of intrinsic transverse momentum both in unpolarized and polarized processes is discussed. We consider inclusive cross sections for pion production in hadronic collisions and for Drell-Yan processes; the results are compared with available experimental ... More
Adaptive cluster expansion for the inverse Ising problem: convergence, algorithm and testsOct 25 2011We present a procedure to solve the inverse Ising problem, that is to find the interactions between a set of binary variables from the measure of their equilibrium correlations. The method consists in constructing and selecting specific clusters of variables, ... More
Fast Inference of Interactions in Assemblies of Stochastic Integrate-and-Fire Neurons from Spike RecordingsFeb 25 2011We present two Bayesian procedures to infer the interactions and external currents in an assembly of stochastic integrate-and-fire neurons from the recording of their spiking activity. The first procedure is based on the exact calculation of the most ... More
Adaptive Cluster Expansion for Inferring Boltzmann Machines with Noisy DataFeb 16 2011We introduce a procedure to infer the interactions among a set of binary variables, based on their sampled frequencies and pairwise correlations. The algorithm builds the clusters of variables contributing most to the entropy of the inferred Ising model, ... More
Protein-Mediated DNA Loops: Effects of Protein Bridge Size and KinksAug 11 2005Nov 16 2005This paper focuses on the probability that a portion of DNA closes on itself through thermal fluctuations. We investigate the dependence of this probability upon the size r of a protein bridge and/or the presence of a kink at half DNA length. The DNA ... More
Theoretical study of collective modes in DNA at ambient temperatureNov 02 1999The instantaneous normal modes corresponding to base pair vibrations (radial modes) and twist angle fluctuations (angular modes) of a DNA molecule model at ambient temperature are theoretically investigated. Due to thermal disorder, normal modes are not ... More
Statistical Mechanics of Torque Induced Denaturation of DNAApr 20 1999Sep 24 1999A unifying theory of the denaturation transition of DNA, driven by temperature T or induced by an external mechanical torque Gamma is presented. Our model couples the hydrogen-bond opening and the untwisting of the helicoidal molecular structure. We show ... More
Segal-type algebraic models of n-typesApr 23 2012Jun 17 2014For each n\geq 1 we introduce two new Segal-type models of n-types of topological spaces: weakly globular n-fold groupoids, and a lax version of these. We show that any n-type can be represented up to homotopy by such models via an explicit algebraic ... More
Indecomposable $1$-factorizations of the complete multigraph $λ K_{2n}$ for every $λ\leq 2n$Nov 10 2016A $1$-factorization of the complete multigraph $\lambda K_{2n}$ is said to be indecomposable if it cannot be represented as the union of $1$-factorizations of $\lambda_0 K_{2n}$ and $(\lambda-\lambda_0) K_{2n}$, where $\lambda_0<\lambda$. It is said to ... More
On the Power-Law Tails of Vote Distributions in Proportional ElectionsJan 25 2016In proportional elections with open lists the excess of preferences received by candidates with respect to the list average is known to follow a universal lognormal distribution. We show that lognormality is broken provided preferences are conditioned ... More
On the density profile of dark matter substructure in gravitational lens galaxiesJun 04 2014Jul 02 2014We consider three extensions of the Navarro, Frenk and White (NFW) profile and investigate the intrinsic degeneracies among the density profile parameters on the gravitational lensing effect of satellite galaxies on highly magnified Einstein rings. In ... More
Chimera states in pulse coupled neural networks: the influence of dilution and noiseJun 28 2016We analyse the possible dynamical states emerging for two symmetrically pulse coupled populations of leaky integrate-and-fire neurons. In particular, we observe broken symmetry states in this set-up: namely, breathing chimeras, where one population is ... More
Comonad Cohomology of Track CategoriesJan 15 2018Apr 03 2018We define a comonad cohomology of track categories and we show it is linked by a long exact sequence to its Dwyer-Kan-Smith cohomology . Under mild hypothesis on the track category, we show that its comonad cohomology coincides, up to dimension shift, ... More
Approaching Maximum Embedding Efficiency on Small Covers Using Staircase-Generator CodesAug 10 2015We introduce a new family of binary linear codes suitable for steganographic matrix embedding. The main characteristic of the codes is the staircase random block structure of the generator matrix. We propose an efficient list decoding algorithm for the ... More
Modification of the Lifshitz-Kosevich formula for anomalous quantum oscillations in inverted insulatorsApr 21 2017It is generally believed that quantum oscillations are a hallmark of a Fermi surface and the oscillations constitute the ringing of it. Recently, it was understood that in order to have well defined quantum oscillations you do not only not need well defined ... More
Multi-valued boundary value problems involving Leray-Lions operators and discontinuous nonlinearitiesFeb 13 2003We prove an existence result for a class of Dirichlet boundary value problems with discontinuous nonlinearity and involving a Leray-Lions operator. The proof combines monotonicity methods for elliptic problems, variational inequality techniques and basic ... More
Modularity and Optimality in Social ChoiceApr 20 2010Marengo and the second author have developed in the last years a geometric model of social choice when this takes place among bundles of interdependent elements, showing that by bundling and unbundling the same set of constituent elements an authority ... More
Trajectories in phase diagrams, growth processes and computational complexity: how search algorithms solve the 3-Satisfiability problemSep 26 2000Most decision and optimization problems encountered in practice fall into one of two categories with respect to any particular solving method or algorithm: either the problem is solved quickly (easy) or else demands an impractically long computational ... More
Dynamics of fully coupled rotators with unimodal and bimodal frequency distributionAug 04 2015We analyze the synchronization transition of a globally coupled network of N phase oscillators with inertia (rotators) whose natural frequencies are unimodally or bimodally distributed. In the unimodal case, the system exhibits a discontinuous hysteretic ... More
Parametric Connectives in Disjunctive Logic ProgrammingNov 07 2003Disjunctive Logic Programming (\DLP) is an advanced formalism for Knowledge Representation and Reasoning (KRR). \DLP is very expressive in a precise mathematical sense: it allows to express every property of finite structures that is decidable in the ... More
Do radio core-halos and cold fronts in non major merging clusters originate from the same gas sloshing?Jan 12 2008We show an interesting correlation between the surface brightness and temperature structure of the relaxed clusters RXJ1720.1+2638 and MS1455.0+2232, hosting a pair of cold fronts, and their central core--halo radio source. We discuss the possibility ... More
On the uniqueness of complete biconservative surfaces in $\mathbb{R}^3$Nov 20 2017We study the uniqueness of complete biconservative surfaces in the Euclidean space $\mathbb{R}^3$, and prove that the only complete biconservative regular surfaces in $\mathbb{R}^3$ are either $CMC$ or certain surfaces of revolution. In particular, any ... More
On the Configuration Spaces of Grassmannian ManifoldsNov 22 2013Let $\mathcal{F}_h^i(k,n)$ be the $i$th ordered configuration space of all distinct points $H_1,\ldots,H_h$ in the Grassmannian $Gr(k,n)$ of $k$-dimensional subspaces of $\mc^n$, whose sum is a subspace of dimension $i$. We prove that $\mathcal{F}_h^i(k,n)$ ... More
Braid groups in complex GrassmanniansNov 22 2013We describe the fundamental group and second homotopy group of ordered $k-$point sets in $Gr(k,n)$ generating a subspace of fixed dimension.
Homology graph of real arrangements and monodromy of Milnor FiberJun 11 2016Mar 30 2017We study the first homology group of the Milnor fiber of sharp arrangements in the real projective plane. Our work relies on the minimal Salvetti complex of the deconing arrangement and its boundary map. We describe an algorithm which computes possible ... More
Improvements on the distribution of maximal segmental scores in a Markovian sequenceMar 07 2018Let $(A_i)_{i \geq 0}$ be a finite state irreducible aperiodic Markov chain and $f$ a lattice score function such that the average score is negative and positive scores are possible. Define $S_0:=0$ and $S_k:=\sum_{i=1}^k f(A_i)$ the successive partial ... More
Asymptotic normality and combinatorial aspects of the prefix exchange distance distributionApr 16 2016The prefix exchange distance of a permutation is the minimum number of exchanges involving the leftmost element that sorts the permutation. We give new combinatorial proofs of known results on the distribution of the prefix exchange distance for a random ... More
Uniqueness and non-degeneracy for a nuclear nonlinear Schrödinger equationMay 06 2014We prove the uniqueness and non-degeneracy of positive solutions to a cubic nonlinear Schr\"odinger (NLS) type equation that describes nucleons. The main difficulty stems from the fact that the mass depends on the solution itself. As an application, we ... More
Lambda and Lambda-bar polarization as a measurement of distribution and fragmentation functionsOct 16 2000A combined analysis of the polarization vector of the Lambda baryons produced in DIS processes may give a relevant insight of the hadronization process which governs the transition from partons to physical hadrons and precise indications on the mechanisms ... More
Single-Spin Asymmetries in $p^\uparrow p \to πX$ and Chiral SymmetryMar 12 1997We study a possible origin of single spin asymmetries in the large $p_T$ inclusive production of hadrons in the scattering of unpolarized protons or leptons on transversely polarized nucleons. Such asymmetry is related to the single-spin asymmetry for ... More
Single Spin Asymmetries in Inclusive Hadron ProductionApr 24 1996The general formalism to describe single spin asymmetries in hadron-hadron high energy and large $p_T$ inclusive production within the QCD-improved parton model and assuming the factorization theorem to hold for higher twist contributions is discussed. ... More
Single spin asymmetry for $p^{\uparrow}p \to πX$ in perturbative QCDMar 10 1995Oct 03 1995Within the QCD-improved parton model and assuming the factorization theorem to hold in the helicity basis and for higher twist contributions, we show how non zero single spin asymmetries in hadron-hadron high energy and moderately large $p_T$ inclusive ... More
Novel constraints on non-cold (non-thermal) Dark Matter from Lyman-$α$ forest dataJun 21 2018Oct 16 2018In this paper we present an efficient method for constraining both thermal and non-thermal Dark Matter (DM) scenarios with the Lyman-$\alpha$ forest, based on a simple and flexible parametrisation capable to reproduce the small scale clustering signal ... More
Equidistribution of jellium energy for Coulomb and Riesz InteractionsSep 13 2016For general dimension $d$ we prove the equidistribution of energy at the micro-scale in $\mathbb R^d$, for the optimal point configurations appearing in Coulomb gases at zero temperature. At the microscopic scale, i.e. after blow-up at the scale corresponding ... More
Renormalized energy equidistribution and local charge balance in 2D Coulomb systemsJul 12 2013Feb 12 2014We consider two related problems: the first is the minimization of the "Coulomb renormalized energy" of Sandier-Serfaty, which corresponds to the total Coulomb interaction of point charges in a uniform neutralizing background (or rather variants of it). ... More
Maximum Likelihood Estimation of Gaussian Cluster Weighted Models and Relationships with Mixtures of RegressionJul 12 2012Aug 08 2013Cluster-weighted modeling (CWM) is a mixture approach for modeling the joint probability of a response variable and a set of explanatory variables. The parameters are estimated by means of the expectation-maximization algorithm according to the maximum ... More
A general formalism for single and double spin asymmetries in inclusive hadron productionDec 16 2004We present a calculation of single and double spin asymmetries for inclusive hadron production in hadronic collisions. Our approach is based on Leading Order (LO) perturbative QCD and generalized factorization theorems, with full account of intrinsic ... More
Phenomenology of transverse single spin asymmetries in inclusive processesMay 09 2000A phenomenological description of single transverse spin asymmetries for the inclusive production of hadrons in proton-proton and lepton-proton processes is discussed within pQCD and a straightforward generalization of the factorization theorem with the ... More
Lambda and Lambda-bar polarization in polarized DISJan 29 2000We consider the polarization of Lambda + Lambda-bar baryons produced in polarized Deep Inelastic Scattering at leading order, with various spin configurations: longitudinally polarized leptons and unpolarized nucleon; unpolarized leptons and longitudinally ... More
Single spin asymmetries in polarized proton-proton, polarized antiproton-proton inclusive processesOct 02 1998Single spin asymmetries in polarized proton(antiproton) + proton -> pion + X have been measured to be large. They can be understood within perturbative QCD by introducing new k_perp and spin dependences in fragmentation and/or distribution functions. ... More
Powers of edge idealsNov 26 2011Nov 30 2011We compute the Betti numbers for all the powers of initial and final lexsegment edge ideals. For the powers of the edge ideal of an anti-$d-$path, we prove that they have linear quotients and we characterize the normally torsion-free ideals. We determine ... More
Phenomenology of single spin asymmetries in p(transv. polarized)-p -> pion + XJan 28 1999Jun 04 1999A phenomenological description of single transverse spin effects in hadron-hadron inclusive processes is proposed, assuming a generalized factorization scheme and pQCD hard interactions. The transverse momentum, k_T, of the quarks inside the hadrons and ... More
Towards a first estimate of the gluon Sivers function from $A_N$ data in $pp$ collisions at RHICJun 09 2015Dec 09 2015Within a generalized parton model approach, with inclusion of spin and intrinsic transverse momentum effects, we show how the latest, highly precise, midrapidity data on the transverse single spin asymmetry measured in $pp\to\pi^0\, X$ by the PHENIX Collaboration ... More