The spontaneous generation of magnetic and chromomagnetic fields at high temperature in the Standard Model

The spontaneous generation of the magnetic and chromomagnetic fields at high temperature is investigated in the Standard Model. The consistent effective potential including the one-loop and the daisy diagrams of all boson and fermion fields is calculated. The mixing of the generated fields due to the quark loop diagram is studied in detail. It is found that the quark contribution increases the magnetic and chromomagnetic field strengths as compared with the separate generation of fields. The magnetized vacuum state is stable due to the magnetic gauge field masses included in the daisy diagrams. Some applications of the results obtained are discussed.Comment: 9 pages, 2 tables, 2 figures, LaTeX with svjour clas

The polarization tensor of neutral gluons in external fields at high temperature

The one-loop polarization operator of neutral gluons in the background constant Abelian isotopic, $H_{3}$, and hypercharge, $H_{8}$, chromomagnetic fields combined with $A_0$ electrostatic potential at high temperature is calculated. The case when $A_0=0$ is investigated separately. The proper time method is applied. It is found that neutral gluons do not acquire magnetic masses in the background fields, in contrast to the charged ones. The application of the results are discussed.Comment: 13 pages, 1 figur

The spontaneous generation of magnetic fields at high temperature in a supersymmetric theory

The spontaneous generation of magnetic and chromomagnetic fields at high temperature in the minimal supersymmetric standard model (MSSM) is investigated. The consistent effective potential including the one-loop and the daisy diagrams of all bosons and fermions is calculated and the magnetization of the vacuum is observed. The mixing of the generated fields due to the quark and s-quark loop diagrams and the role of superpartners are studied in detail. It is found that the contribution of these diagrams increases the magnetic and chromomagnetic field strengths as compared with the case of a separate generation of fields. The magnetized vacuum state is found to be stable due to the magnetic masses of gauge fields included in the daisy diagrams. Applications of the results obtained are discussed. A comparison with the standard model case is done.Comment: 14 pages, 2 figures, 3 table

Renormalizability and model independent description of Z' signals at low energies

Model independent search for signals of heavy Z' gauge bosons in low-energy four-fermion processes is analyzed. It is shown that the renormalizability of the underlying theory containing Z', formulated as a scattering in the field of heavy virtual states, can be implemented in specific relations between different processes. Considering the two-Higgs-doublet model as the low-energy basis theory, the two types of Z' interactions with light particles are found to be compatible with the renormalizability. They are called the Abelian and the "chiral" couplings. Observables giving possibility to uniquely detect Z' in both cases are introduced.Comment: 11 pages, 5 figures, RevTeX. The text of the paper is rewritten to be more clear and precis