OpenAIRE: Open Access Infrastructure for Research in Europe
http://hdl.handle.net/10486/129768
(Resultados de investigación financiados por el 7PM y H2020 de la UE)Sat, 10 Apr 2021 15:14:46 GMT2021-04-10T15:14:46ZConstructing SU(N) fractional instantons
http://hdl.handle.net/10486/694430
Constructing SU(N) fractional instantons
González-Arroyo España, Antonio
We study self-dual SU(N) gauge eld con gurations on the 4 torus with twisted boundary conditions, known as fractional instantons. Focusing on the minimum non-zero action case, we generalize the constant eld strength solutions discovered by `t Hooft and valid for certain geometries. For the general case, we construct the vector potential and eld strength in a power series expansion in a deformation parameter of the metric. The next to leading term is explicitly computed. The methodology is an extension of that used by the author for SU(2) fractional instantons and for vortices in two-dimensional Abelian Higgs models. Obviously, these solutions can also be seen as self-dual con gurations in R4 having a crystal structure, where each node of the crystal carries a topological charge of 1/N
Mon, 24 Feb 2020 00:00:00 GMThttp://hdl.handle.net/10486/6944302020-02-24T00:00:00ZNo go for a flow
http://hdl.handle.net/10486/694383
No go for a flow
Carta, Federico; Mininno, Alessandro
We prove that a very large class of 15502 general Argyres-Douglas theories can-
not admit a UV lagrangian which ows to them via the Maruyoshi-Song supersymmetry
enhancement mechanism. We do so by developing a computer program which brute-force
lists, for any given 4d N = 2 superconformal theory TIR, all possible UV candidate su-
perconformal lagrangians TUV satisfying some necessary criteria for the supersymmetry
enhancement to happen. We argue that this is enough evidence to conjecture that it is
impossible, in general, to find new examples of Maruyoshi-Song lagrangians for generalized Argyres-Douglas theories. All lagrangians already known are, on the other hand, recovered and confirmed in our scan. Finally, we also develop another program to compute efficiently Coulomb branch spectrum, masses, couplings and central charges for (G, G’) Argyres-Douglas theories of arbitrarily high rank
Fri, 22 May 2020 00:00:00 GMThttp://hdl.handle.net/10486/6943832020-05-22T00:00:00ZInstanton corrections and emergent strings
http://hdl.handle.net/10486/694382
Instanton corrections and emergent strings
Baume, Florent; Marchesano, Fernando; Wiesner, Max
We study limits of infinite distance in the moduli space of 4d N = 2 string compactifications, in which instanton effects dominate. We first consider trajectories in the hypermultiplet moduli space of type IIB Calabi-Yau compactifications. We observe a correspondence between towers of D-brane instantons and D-brane 4d strings, such that the lighter the string the more relevant the instanton effects are. The dominant instantons modify the classical trajectory such that the lightest D-brane string becomes tensionless even faster, while the other strings are prevented to go below the fundamental string tension. This lightest string is dual to a fundamental type IIB string and realises the Emergent String Conjecture. We also consider the vector multiplet moduli space of type I string theory on K3 ×T2, where quantum corrections can also become significant. Naively, we only find trajectories that correspond to decompactification limits, in apparent contradiction with the picture obtained in some dual setup
Mon, 27 Apr 2020 00:00:00 GMThttp://hdl.handle.net/10486/6943822020-04-27T00:00:00ZProbing dark matter freeze-in with long-lived particle signatures: MATHUSLA, HL-LHC and FCC-hh
http://hdl.handle.net/10486/694367
Probing dark matter freeze-in with long-lived particle signatures: MATHUSLA, HL-LHC and FCC-hh
No, J. M.; Tunney, P.; Zaldivar, B.
Collider searches for long-lived particles yield a promising avenue to probe the freeze-in production of Dark Matter via the decay of a parent particle. We analyze the prospects of probing the parameter space of Dark Matter freeze-in from the decay of neutral parent particles at the LHC and beyond, taking as a case study a freeze-in Dark Matter scenario via the Standard Model Higgs. We obtain the projected sensitivity of the proposed MATHUSLA surface detector (for MATHUSLA100 and MATHUSLA200 configurations) for long-lived particle searches to the freeze-in Dark Matter parameter space, and study its complementarity to searches by ATLAS and CMS at HL-LHC, as well as the interplay with constraints from Cosmology: Big-Bang Nucleosynthesis and Lyman-α forest observations. We then analyze the improvement in sensitivity that would come from a forward detector within a future 100 TeV pp-collider. In addition, we discuss several technical aspects of the present Dark Matter freeze-in scenario: the role of the electroweak phase transition; the inclusion of thermal masses, which have been previously disregarded in freeze-in from decay studies; the impact of 2 → 2 scattering processes on the Dark Matter relic abundance; and the interplay between freeze-in and super-WIMP Dark Matter production mechanisms
Wed, 04 Mar 2020 00:00:00 GMThttp://hdl.handle.net/10486/6943672020-03-04T00:00:00Z