Publications (27)
Physics and phenomenology of weakly magnetized, relativistic astrophysical shock waves
A. Vanthieghem, M. Lemoine, I. Plotnikov +4
Weakly magnetized, relativistic collisionless shock waves are not only the natural offsprings of relativistic jets in high-energy astrophysical sources, they are also associated wi…
Momentum space treatment of inclusive neutrino scattering off the deuteron and trinucleons
J. Golak, R. Skibinski, K. Topolnicki +4
The , , , $ν_l + {^2{\rm H}}…
A Non-Perturbative Superpotential With Symmetry
R. Donagi, A. Grassi, E. Witten
We compute the non-perturbative superpotential in -theory compactification to four dimensions on a complex three-fold , where is a rational elliptic surface. I…
Electronic structure of clusters (LiBC)_n: n=1, 2, 4
G. M. Lombardo, A. Grassi, G. Forte +3
A crystalline form of LiBC is known which has been predicted to be superconducting, with a Tc comparable to that of MgB_2. In both compounds, superconductivity is enhanced by the p…
Radiative pion capture in 2H, 3He and 3H
J. Golak, R. Skibinski, K. Topolnicki +5
The , , , $Ï^- + {^3{\rm He}} \rightarrow γ+…
Electron and neutrino scattering off the deuteron in a relativistic framework
A. Grassi, J. Golak, W. N. Polyzou +3
We build a relativistic model to perform calculations of exclusive, semi-exclusive and inclusive unpolarized cross sections and various polarization observables in electron and neu…
Two-step Nonnegative Matrix Factorization Algorithm for the Approximate Realization of Hidden Markov Models
L. Finesso, A. Grassi, P. Spreij
We propose a two-step algorithm for the construction of a Hidden Markov Model (HMM) of assigned size, i.e. cardinality of the state space of the underlying Markov chain, whose -…
Control of autoresonant plasma beat-wave wakefield excitation
M. Luo, C. Riconda, I. Pusztai +3
Autoresonant phase-locking of the plasma wakefield to the beat frequency of two driving lasers offers advantages over conventional wakefield acceleration methods, since it requires…
Electron Weibel Instability in Relativistic Counter-Streaming Plasmas with Flow-Aligned External Magnetic Fields
A. Grassi, M. Grech, F. Amiranoff +3
The Weibel instability driven by two symmetric counter-streaming relativistic electron plasmas, also referred to as current-filamentation instability, is studied in a constant and…
Molecules in clusters: the case of planar LiBeBCNOF built from a triangular form LiOB and a linear four-center species FBeCN
G. Forte, A. Grassi, G. M. Lombardo +3
Krueger some years ago proposed a cluster LiBeBCNOF, now called periodane. His ground-state isomer proposal has recently been refined by Bera et al. using DFT. Here, we take the ap…
Fingerprints of antiaromaticity in the negative ion (LiAl) via an ab initio quantum-chemical study of the equilibrium structure of the inhomogeneous electron liquid
A. Grassi, G. M. Lombardo, G. G. N. Angilella +4
Fingerprints of antiaromaticity in the negative ion (LiAl), this species being realizable via a laser vaporization technique, are revealed by means of an \emph{ab initi…
Divisors on elliptic Calabi-Yau 4-folds and the superpotential in F-theory, I
A. Grassi
Each smooth elliptic Calabi-Yau 4-fold determines both a three-dimensional physical theory (a compactification of ``M-theory'') and a four-dimensional physical theory (using the ``…
Impact of the laser spatio-temporal shape on Breit-Wheeler pair production
A. Mercuri-Baron, M. Grech, F. Niel +4
The forthcoming generation of multi-petawatt lasers opens the way to abundant pair production by the nonlinear Breit-Wheeler process, i.e., the decay of a photon into an electron-p…
Log contractions and equidimensional models of elliptic threefolds
A. Grassi
This work was initially motivated by Miranda's work on elliptic Weierstrass threefolds. Miranda [Mi] describes a smooth equidimensional (flat) model for any elliptic Weierstrass th…
Applications of the chiral potential with the semi-local regularization in momentum space to the disintegration processes
V. Urbanevych, R. SkibiÅski, H. WitaÅa +5
We apply the chiral potential with the momentum space semi-local regularization to the H and He photodisintegration processes and to the (anti)neutrino induced deuteron bre…
Toric Calabi-Yau Fourfolds, Duality Between N=1 Theories and Divisors that Contribute to the Superpotential
V. Braun, P. Candelas, X de la Ossa +1
We study issues related to F-theory on Calabi-Yau fourfolds and its duality to heterotic theory for Calabi-Yau threefolds. We discuss principally fourfolds that are described by re…
Growth rate of self-sustained QED cascades induced by intense lasers
A. Mercuri-Baron, A. A. Mironov, C. Riconda +2
It was suggested [A. R. Bell & J. G. Kirk, PRL 101, 200403 (2008)] that an avalanche of electron-positron pairs can be triggered in the laboratory by a standing wave generated by i…
SMILEI: a collaborative, open-source, multi-purpose particle-in-cell code for plasma simulation
J. Derouillat, A. Beck, F. Pérez +10
SMILEI is a collaborative, open-source, object-oriented (C++) particle-in-cell code. To benefit from the latest advances in high-performance computing (HPC), SMILEI is co-developed…
A multiscale study of electronic structure and quantum transport in -based graphene quantum dots
I. Deretzis, G. Forte, A. Grassi +3
We implement a bottom-up multiscale approach for the modeling of defect localization in islands, i.e. graphene quantum dots with a hexagonal symmetry, by means of…
Bond-order correlation energies for small Si-containing molecules compared with ab initio results from low-order Moller-Plesset perturbation theory
A. Grassi, G. M. Lombardo, G. Forte +3
The present study of small molecules containing silicon has been motivated by (a) the considerable interest being shown currently in the kinetics and reactivity of such molecules,…
The astrophysical -factor and its implications for Big Bang Nucleosynthesis
A. Grassi, G. Mangano, L. E. Marcucci +1
The radiative capture is studied in order to predict the Li primordial abundance. Within a two-body framework, the particle and the deute…
The Singularities of the parameter surface of a minimal elliptic threefold
A. Grassi
Let f : X -> S be any elliptic fibration. If X has dimension 3 and is not uniruled, then X has a minimal model (with terminal singularities) [Mori]. In earlier work we have shown t…
Stretched chemical bonds in Si6H6: A transition from ring currents to localized pi-electrons?
A. Grassi, G. M. Lombardo, R. Pucci +3
Motivated by solid-state studies on the cleavage force in Si, and the consequent stretching of chemical bonds, we here study bond stretching in the, as yet unsynthesized, free spac…
From response functions to cross sections in neutrino scattering off the deuteron and trinucleons
J. Golak, R. Skibinski, K. Topolnicki +4
Response functions, differential cross sections and total cross sections for several (anti)neutrino induced reactions on 2H, 3He and 3H are calculated in momentum space for (anti)n…
Modeling vacancies and hydrogen impurities in graphene: A molecular point of view
G. Forte, A. Grassi, G. M. Lombardo +4
We have followed a "molecular" approach to study impurity effects in graphene. This is thought as the limiting case of an infinitely large cluster of benzene rings. Therefore, we s…
Equilibrium geometries of low-lying isomers of some Li clusters, within Hartree-Fock theory plus bond order or MP2 correlation corrections
A. Grassi, G. M. Lombardo, G. G. N. Angilella +2
In a recent study by Kornath et al. [J. Chem. Phys. 118 (2003) 6957], the Li_n clusters with n=2, 4 and 8 have been isolated in argon matrices at 15 K and characterized by Raman sp…
Equilibrium molecular energies used to obtain molecular dissociation energies and heats of formation within the bond-order correlation approach
A. Grassi, G. M. Lombardo, G. Forte +3
Ab initio calculations including electron correlation are still extremely costly except for the smallest atoms and molecules. Therefore, our purpose in the present study is to empl…