TY  - JOUR
A1  - Camago-Molina, J.E.
A1  - O'Leary, B.
A1  - Porod, W.
A1  - Staub, F.
T1  - Vevacious: a tool for finding the global minima of one-loop effective potentials with many scalars
JF  - European Physical Journal C
N2  - Several extensions of the Standard Model of particle physics contain additional scalars implying a more complex scalar potential compared to that of the Standard Model. In general these potentials allow for charge- and/or color-breaking minima besides the desired one with correctly broken SU(2) L ×U(1) Y . Even if one assumes that a metastable local minimum is realized, one has to ensure that its lifetime exceeds that of our universe. We introduce a new program called Vevacious which takes a generic expression for a one-loop effective potential energy function and finds all the tree-level extrema, which are then used as the starting points for gradient-based minimization of the one-loop effective potential. The tunneling time from a given input vacuum to the deepest minimum, if different from the input vacuum, can be calculated. The parameter points are given as files in the SLHA format (though is not restricted to supersymmetric models), and new model files can be easily generated automatically by the Mathematica package SARAH. This code uses HOM4PS2 to find all the minima of the tree-level potential, PyMinuit to follow gradients to the minima of the one-loop potential, and CosmoTransitions to calculate tunneling times.
KW  - True Vacuum
KW  - One-loop Effective Potential
KW  - Saddle Point
KW  - Minimal Surface Tension
KW  - CMSSM Point
KW  - SM Gauge Group
KW  - Renormalization Scale
KW  - Landau Gauge
KW  - Homotopy Continuation Method
KW  - Gauge-dependent Quantity
KW  - False Vacuum
KW  - Spectrum Generator
KW  - SLHA File
KW  - Tunneling Time
KW  - Charged Scalar Field
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-132110
VL  - 73
IS  - 2588
ER  - 
TY  - JOUR
A1  - Camargo-Molina, J. E.
A1  - Garbrecht, B.
A1  - O'Leary, B.
A1  - Porod, W.
A1  - Staub, F.
T1  - Constraining the Natural MSSM through tunneling to color-breaking vacua at zero and non-zero temperature
JF  - Physics Letters B
N2  - We re-evaluate the constraints on the parameter space of the minimal supersymmetric standard model from tunneling to charge- and/or color-breaking minima, taking into account thermal corrections. We pay particular attention to the region known as the Natural MSSM, where the masses of the scalar partners of the top quarks are within an order of magnitude or so of the electroweak scale. These constraints arise from the interaction between these scalar tops and the Higgs fields, which allows the possibility of parameter points having deep charge- and color-breaking true vacua. In addition to requiring that our electroweak-symmetry-breaking, yet QCD- and electromagnetism-preserving vacuum has a sufficiently long lifetime at zero temperature, also demanding stability against thermal tunneling further restricts the allowed parameter space.
KW  - Supersymmetry
KW  - Vacuum stability
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-118458
VL  - 737
ER  -