41,551 research outputs found
Phase Transitions in the NMSSM
We study phase transitions in the Next-to-Minimal Supersymmetric Standard
Model (NMSSM) with the weak scale vacuum expectation values of the singlet
scalar, constrained by Higgs spectrum and vacuum stability. We find four
different types of phase transitions, three of which have two-stage nature. In
particular, one of the two-stage transitions admits strongly first order
electroweak phase transition, even with heavy squarks. We introduce a
tree-level explicit CP violation in the Higgs sector, which does not affect the
neutron electric dipole moment. In contrast to the MSSM with the CP violation
in the squark sector, a strongly first order phase transition is not so
weakened by this CP violation.Comment: 21 pages, 8 figure
CP Violation in the Higgs Sector and Phase Transition in the MSSM
We investigate the electroweak phase transition in the presence of a large CP
violation in the squark sector of the MSSM. When the CP violation is large,
scalar-pseudoscalar mixing of the Higgs bosons occurs and a large CP violation
in the Higgs sector is induced. It, however, weakens first-order phase
transition before the mixing reaches the maximal. Even when the CP violation in
the squark sector is not so large that the phase transition is strongly first
order, the phase difference between the broken and symmetric phase regions
grows to O(1), which leads to successful baryogenesis, when the charged Higgs
bosons is light.Comment: 18 pages, 6 figures, LaTeX2
Acoustic model adaptation for ortolan bunting (Emberiza hortulana L.) song-type classification
Automatic systems for vocalization classification often require fairly large amounts of data on which to train models. However, animal vocalization data collection and transcription is a difficult and time-consuming task, so that it is expensive to create large data sets. One natural solution to this problem is the use of acoustic adaptation methods. Such methods, common in human speech recognition systems, create initial models trained on speaker independent data, then use small amounts of adaptation data to build individual-specific models. Since, as in human speech, individual vocal variability is a significant source of variation in bioacoustic data, acoustic model adaptation is naturally suited to classification in this domain as well. To demonstrate and evaluate the effectiveness of this approach, this paper presents the application of maximum likelihood linear regression adaptation to ortolan bunting (Emberiza hortulana L.) song-type classification. Classification accuracies for the adapted system are computed as a function of the amount of adaptation data and compared to caller-independent and caller-dependent systems. The experimental results indicate that given the same amount of data, supervised adaptation significantly outperforms both caller-independent and caller-dependent systems
- …