Multi-Component Dark Matter and Extensions of the Standard Model Scalar Sector

In the the Standard Model of Elementary Interactions (SM) there is only one scalar particle, a Higgs boson. In this thesis various models of elementary interactions with extended scalar sectors were discussed: the O(N) Model, Two-Component Dark Matter Model (2CDMM), Two-Higgs Doublet Model (2HDM) and Two-Higgs Doublet Model with Scalar Singlet Dark Matter candidate (2HDMS). In the framework of these models, we discussed various theoretical issues: perturbative unitarity, vacuum stability of the scalar potential, electroweak symmetry breaking, triviality and little hierarchy problem. Various experimental constraints were imposed on the models: - electroweak precision constraints on S, T, U parameters - b physics constraints on charged Higgs boson in 2HDM and 2HDMS - fit to the LHC signal stregths from 125 GeV scalar - limits on Higgs invisible decays - Dark Matter relic density limits from WMAP/Planck - Dark Matter direct detection limits The O(N) Model contains extra N scalar particles, that are singlets of the SU(3) × SU(2) × U(1) gauge group. The model provides multiple Dark Matter (DM) candidates. We discussed DM density evolution in scenarios with and without thermalization in the very early Universe. The parameter space of the model was constrained also with limits from direct detection experiments. We also discussed a model with one scalar and one fermion DM candidates (2CDMM). The dynamics of evolution of DM density in the Universe was discussed and solutions to a set of Boltzmann equations were shown. The parameter space of the model was severely constrained by cosmological data. The Two-Higgs Doublet Model was introduced to explain the enhancement in the diphoton decay mode of the 125 GeV boson observed at the LHC. Possibilities of such enhancement and consequences for the parameter space of the model were studied in various scenarios of mass hierarchy of the Higgs bosons present in the theory. We also discussed a Two-Higgs Doublet Model with a Scalar Singlet Dark Matter candidate (2HDMS). All applicable constraints on this model were discussed, together with a fit to the LHC 125 GeV signal strengths. We discussed a possibility of isospin-violation in DM - nucleon interaction, that may help to reconcile the results from xenon-based direct detection experiment with CDMS-Si

Two-Component Dark Matter

We study an extension of the Standard Model (SM) with two interacting cold Dark Matter (DM) candidates: a neutral Majorana fermion ($\nu$) and a neutral scalar singlet ($\varphi$). The scalar $\varphi$ interacts with the SM through the "Higgs portal" coupling while $\nu$ at the tree level interacts only with $\varphi$ through Yukawa interactions. The relic abundance of $\nu$ and $\varphi$ is found by solving the Boltzmann equations numerically; for the case $m_\nu > m_\varphi$ we also derive a reliable approximate analytical solution. Effects of the interaction between the two DM components are discussed. A scan over the parameter space is performed to determine the regions consistent with the WMAP data for DM relic abundance, and with the XENON100 direct detection limits for the DM-nucleus cross section. We find that although a large region of the parameter space is allowed by the WMAP constraints, the XENON100 data severely restricts the parameter space. Taking into account only amplitudes generated at the tree level one finds three allowed regions for the scalar mass: $m_\varphi \sim 62.5$ GeV (corresponding to the vicinity of the Higgs boson resonance responsible for $\varphi\varphi$ annihilation into SM particles), $m_\varphi \simeq 130-140$ GeV and m_\varphi \gesim 3 TeV. 1-loop induced $\nu$-nucleon scattering has been also calculated and discussed. A possibility of DM direct detection by the CREST-II experiment was considered.Comment: 22 pages, 17 figures; v2: references added, published in JHEP, v3: misspelled authors name correcte

Isospin-violating dark-matter-nucleon scattering via two-Higgs-doublet-model portals

We show that in a multi-Higgs model in which one Higgs fits the LHC 125 GeV state, one or more of the other Higgs bosons can mediate DM-nucleon interactions with maximal DM isospin violation being possible for appropriate Higgs-quark couplings, independent of the nature of DM. We then consider the explicit example of a Type II two-Higgs-doublet model, identifying the h or H as the 125 GeV state while the H or h, respectively, mediates DM-nucleon interactions. Finally, we show that if a stable scalar, S, is added then it can be a viable light DM candidate with correct relic density while obeying all direct and indirect detection limits.Comment: Two subsections are added to address the collider bounds from direct search for heavy Higgs bosons and from jet plus missing energy final states. The LUX (2013) bound considered in the previous version is replaced by the latest LUX (2016) bound and the SuperCDMS limit is taken into account. The conclusions remain unchanged. A very minor change made in the title and new references include

Two-Higgs-Doublet Models and Enhanced Rates for a 125 GeV Higgs

We examine the level of enhancement that can be achieved in the ZZ and \gamma\gamma channels for a two-Higgs-doublet model Higgs boson (either the light h or the heavy H) with mass near 125 GeV after imposing all constraints from LEP data, B physics, precision electroweak data, vacuum stability, unitarity and perturbativity. The latter constraints restrict substantially the possibilities for enhancing the gg -> h -> \gamma\gamma or gg -> H -> \gamma\gamma signal relative to that for the SM Higgs, hSM. Further, we find that a significant enhancement of the gg -> h -> \gamma\gamma or gg -> H -> \gamma\gamma signal in Type II models is possible only if the gg -> h -> ZZ or gg -> H -> ZZ mode is even more enhanced, a situation disfavored by current data. In contrast, in the Type I model one can achieve enhanced rates in the \gamma\gamma final state for the h while having the ZZ mode at or below the SM rate - the largest [gg -> h -> \gamma\gamma]/[gg -> hSM -> \gamma\gamma] ratio found is of order ~1.3 when the two Higgs doublet vacuum expectation ratio is tan\beta = 4 or 20 and the charged Higgs boson has its minimal LEP-allowed value of m_{H^\pm} = 90 GeV.Comment: 15 pages, 9 figure

Unique dynamic crossover in supercooled x,3-dihydroxypropyl acrylate (x = 1, 2) isomers mixture

The previtreous dynamics in glass forming monomer, glycerol monoacrylate (GMA), using broadband dielectric spectroscopy (BDS) was tested. Measurements revealed the clear dynamic crossover at temperature $T_B = 254$ K and the time scale $\tau(T_B) = 5.4$ ns for the primary (structural) relaxation time and no hallmarks for the crossover for the DC electric conductivity $\sigma_{DC}$. This result was revealed via the derivative-based and distortions-sensitive analysis $dln{H_{a}}/d(1/T)$ vs. $1/T$, where $H_a$ is for the apparent activation energy. Subsequent tests of the fractional Debye-Stokes-Einsten relation $\sigma_{DC}(\tau_{\alpha})^S = const$ showed that the crossover is associated with $S = 1$ (for $T>T_B$)->$S = 0.84$ (for $T<T_B$). The crossover is associated with the emergence of the secondary beta relaxation which smoothly develops deeply into the solid amorphous phase below the glass temperature $T_g$

O sztuce wykorzystywania „sposobności” – kilka słów o edycjach książek Antoniego Ferdynanda Ossendowskiego

Good editor is invaluable for the writer – particularly when the author is a controversial celebrity used to living like a lord and not all of his books are really noteworthy. Antoni Ferdynand Ossendowski also was looking for wealthy backer. Tactics that he practiced seems to be surprising even today. He gave more than one title to some of his novels, divided some books into parts, re-used names and motives and prepared books to order. He did not have anything against writing for owner of chocolate factory. In this article I characterize different methods of printing and distributing even not very good books. I also analyze editor’s influence on the content and artwork of the publication.Dobry wydawca jest dla literata bezcenny. Zwłaszcza jeśli sam pisarz to postać kontrowersyjna, przywykła do życia na wysokiej stopie, a jego powieści prezentują bardzo nierówny poziom. Poszukiwania wydawcy były stałym elementem życia Antoniego Ferdynanda Ossendowskiego. Pisarz nieustannie zabiegał o zainteresowanie zamożnych mecenasów. Troska o kwestie finansowe sprawiła zaś, że stosował zaskakujące nawet dzisiaj praktyki. Nie przeszkadzało mu wydawanie jednej powieści pod kilkoma tytułami, dzielenie książki na części i dystrybucja każdej z nich osobno (pod oddzielnym tytułem), powracanie do raz wykorzystanych motywów czy pisanie na zamówienie… fabrykanta czekolady. W artykule analizuję różne taktyki stosowane przez literata okresu międzywojennego pozwalające na zwiększanie nakładów, szybkie wznawianie i wydawanie drukiem nawet powieści nieszczególnie godnych uwagi. Omawiam, jaki wpływ na zawartość książki ma dobór wydawcy oraz przyglądam się szacie graficznej jego publikacji