Giuseppe Torri

Higgsing M2-brane theories

Connections between dierent M2-brane theories are established via the Higgs mechanism, which can be most eciently studied on brane tilings. This leads to several M2-brane models, with brane tilings or Chern-Simons levels which have not been considered so far. The moduli spaces of these models are identied and examined in detail. The toric diagrams are constructed using Kasteleyn matrices and the forward algorithm.

The Hilbert Series of Adjoint SQCD

Abstract We use the plethystic exponential and the Molien–Weyl formula to compute the Hilbert series (generating functions), which count gauge invariant operators in N = 1 supersymmetric SU ( N c ) , Sp ( N c ) , SO ( N c ) and G 2 gauge theories with 1 adjoint chiral superfield, fundamental chiral superfields, and zero classical superpotential. The structure of the chiral ring through the generators and relations between them is examined using the plethystic logarithm and the character expansion technique. The palindromic numerator in the Hilbert series implies that the classical moduli space of adjoint SQCD is an affine Calabi–Yau cone over a weighted projective variety.

Hilbert series for flavor invariants of the Standard Model

The Hilbert series is computed for the lepton flavor invariants of the Standard Model with three generations including the right-handed neutrino sector needed to generate light neutrino masses via the see-saw mechanism. We also compute the Hilbert series of the quark flavor invariants for the case of four generations.

M2-branes and Fano 3-folds

A class of supersymmetric gauge theories arising from M2-branes probing Calabi–Yau 4-folds which are cones over smooth toric Fano 3-folds is investigated. For each model, the toric data of the mesonic moduli space are derived using the forward algorithm. The generators of the mesonic moduli space are determined using the Hilbert series. The spectrum of scaling dimensions for chiral operators is computed.

Role of surface heat fluxes underneath cold pools

Abstract The role of surface heat fluxes underneath cold pools is investigated using cloud‐resolving simulations with either interactive or horizontally homogenous surface heat fluxes over an ocean and a simplified land surface. Over the ocean, there are limited changes in the distribution of the cold pool temperature, humidity, and gust front velocity, yet interactive heat fluxes induce more cold pools, which are smaller, and convection is then less organized. Correspondingly, the updraft mass flux and lateral entrainment are modified. Over the land surface, the heat fluxes underneath cold pools drastically impact the cold pool characteristics with more numerous and smaller pools, which are warmer and more humid and accompanied by smaller gust front velocities. The interactive fluxes also modify the updraft mass flux and reduce convective organization. These results emphasize the importance of interactive surface fluxes instead of prescribed flux boundary conditions, as well as the formulation of surface heat fluxes, when studying convection.

A Lagrangian Study of Precipitation-Driven Downdrafts*

Precipitation-driven downdrafts are an important component of deep convective systems. They stabilize the atmosphere by injecting relatively cold and dry air into the boundary layer. They have also been invoked as responsible for balancing surface latent and sensible heat fluxes in the heat and moisture budget of tropical boundary layers. This study is focused on precipitation-driven downdrafts and basic aspects of their dynamics in a case of radiative‐convective equilibrium. Using Lagrangian particle tracking, it is shown that such downdrafts have very low initial heights, with most parcels originating within 1.5km from the surface. The tracking is also used to compute the contribution of downdrafts to the flux of moist static energy at the top of the boundary layer, and it is found that this is on the same order of magnitude as the contribution due to convective updrafts, but much smaller than that due to turbulent mixing across the boundary layer top in the environment. Furthermore, considering the mechanisms driving the downdrafts, it is shown that the work done by rain evaporation is less than half that done by condensate loading.

A Survey of Precipitation-Induced Atmospheric Cold Pools over Oceans and Their Interactions with the Larger-Scale Environment

Pools of air cooled by partial rain evaporation span up to several hundreds of kilometers in nature and typically last less than 1 day, ultimately losing their identity to the large-scale flow. These fundamentally differ in character from the radiatively-driven dry pools defining convective aggregation. Advancement in remote sensing and in computer capabilities has promoted exploration of how precipitation-induced cold pool processes modify the convective spectrum and life cycle. This contribution surveys current understanding of such cold pools over the tropical and subtropical oceans. In shallow convection with low rain rates, the cold pools moisten, preserving the near-surface equivalent potential temperature or increasing it if the surface moisture fluxes cannot ventilate beyond the new surface layer; both conditions indicate downdraft origin air from within the boundary layer. When rain rates exceed

Rain evaporation and moist patches in tropical boundary layers

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