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)

Electron and positron fluxes in primary cosmic rays measured with the alpha magnetic spectrometer on the international space station

Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at &sim;30GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.</p