Theoretical and Phenomenological Study of Grand Unified Models

Doctoral Dissertation uoadl:1308959 660 Read counter

Unit:
Τομέας Πυρηνικής Φυσικής και Φυσικής Στοιχειωδών Σωματιδίων
Library of the School of Science
Deposit date:
2015-06-11
Year:
2015
Author:
Κατσικάτσου Αικατερίνη
Dissertation committee:
Αθανάσιος Λαχανάς, Καθηγητής (Επιβλέπων), Γεώργιος Διαμάντης Αναπληρωτής Καθηγητής, Ξάνθος Μαϊντάς Επίκουρος Καθηγητής
Original Title:
Θεωρητική και Φαινομενολογική Μελέτη Ενοποιημένων Υποδειγμάτων του Καθιερωμένου Προτύπου
Languages:
Greek
Translated title:
Theoretical and Phenomenological Study of Grand Unified Models
Summary:
Supersymmetric Grand Unified Theories (SUSY GUTs) are the most natural
extension of the Standard model unifying electroweak and strong forces. Despite
their indubitable virtues, one of their shortcomings is the large number of
parameters used to describe the high energy thresholds (HET), which are hard to
handle.
We present a new method according to which the effects of the HETs, in any GUT
model, can be described by fewer parameters that are randomly produced from the
original set of the parameters of the model. In this way, regions favoured by
the experimental data are easier to locate, avoiding a detailed and time
consuming exploration of the multidimensional parameter space. To check the
efficiency of this method, we directly apply it to a SUSY SO(10) GUT model
which uses the Dimopoulos-Wilczek mechanism. We show that the demand of gauge
coupling unification, in conjunction with precision data, locates regions of
the parameter space in which the strong coupling a_strong is within the
experimental limits, along with a proton lifetime, above the current
experimental bounds.
We cross-check these preferred regions by applying constraints based on the
results of the LHC for the mass of the Higgs particle and the supersymmetry
exclusion limits.
Keywords:
Supersymmetry, Grand unified theory: SO(10), Nucleon decay, Threshold effect, Higgs particle
Index:
No
Number of index pages:
0
Contains images:
Yes
Number of references:
170
Number of pages:
XIV, 142
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