The evolution of vacuum states and phase transitions in 2HDM during cooling of Universe

We consider the evolution of the ground state in the Two Higgs Doublet Model during cooling down of the Universe after the Big Bang. Different regions in the space of free parameters of this model correspond to different sequences of thermal phase transitions. We discuss different paths of thermal evolution and corresponding evolution of physical properties of the system for different modern values of the parameters.Comment: 28 pages, 12 figure

Evolution of Universe to the present inert phase

We assume that current state of the Universe can be described by the Inert Doublet Model, containing two scalar doublets, one of which is responsible for EWSB and masses of particles and the second one having no couplings to fermions and being responsible for dark matter. We consider possible evolutions of the Universe to this state during cooling down of the Universe after inflation. We found that in the past Universe could pass through phase states having no DM candidate. In the evolution via such states in addition to a possible EWSB phase transition (2-nd order) the Universe sustained one 1-st order phase transition or two phase transitions of the 2-nd order.Comment: 19 pages, 3 figure

The phase evolution of the Universe during its cooling down in 2HDM

Two Higgs Doublet Model at different values of parameters realizes ground state (vacuum) with different properties. The parameters of the Gibbs potential are varied during cooling down of the Universe after Big Bang. At this variation properties of vacuum state can vary, Universe suffers phase transitions. The evolution of phase states and chains of phase transitions can be much more diverse than in Standard Model with single Higgs doublet. We analyzed phase history of earlier Universe for each set of parameters and find sets of modern parameters, responsible for different chains of thermal phase transitions

Evolution of Universe to the present inert phase

We assume that current state of the Universe can be described by the Inert Doublet Model, containing two scalar doublets, one of which is responsible for EWSB and masses of particles and the second one having no couplings to fermions and being responsible for dark matter. We consider possible evolutions of the Universe to this state during cooling down of the Universe after inflation. We found that in the past Universe could pass through phase states having no DM candidate. In the evolution via such states in addition to a possible EWSB phase transition (2-nd order) the Universe sustained one 1-st order phase transition or two phase transitions of the 2-nd order.Comment: 19 pages, 3 figure

Particle Astrophysics in Space with an Antimatter Large Acceptance Detector in Orbit (ALADINO)

The note describes a proposal for a large acceptance magnetic spectrometer based on a novel superconducting magnet technology, equipped with a silicon tracker and a 3D isotropic calorimeter. ALADINO (Antimatter Large Acceptance Detector IN Orbit) is conceived to study antimatter components of the cosmic radiation in an unexplored energy window which can shed light on new phenomena related to the origin and evolution of the Universe, as well as on the origin and propagation of cosmic rays in our galaxy. The main science themes addressed by this mission are therefore the origin and composition of the Universe (by means of direct search for primordial anti-nuclei in the Cosmic Ray (CR) flux and indirect search for Dark Matter signals in the CR anti-particle fluxes) as well as the origin and propagation of CR in the Galaxy (by means of precise measurements of the energy spectra and chemical composition of the CR)

High statistics measurement of the positron fraction in primary cosmic rays of 0.5-500 GeV with the alpha magnetic spectrometer on the international space station

A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above &sim;200GeV the positron fraction no longer exhibits an increase with energy.</p