55 research outputs found
Gravitational waves from the first order electroweak phase transition in the symmetric singlet scalar model
Among various scenarios of baryon asymmetry of the Universe, electroweak
baryogenesis is directly connected with physics of the Higgs sector. We discuss
spectra of gravitational waves which are originated by the strongly first order
phase transition at the electroweak symmetry breaking, which is required for a
successful scenario of electroweak baryogenesis. In the symmetric singlet
scalar model, the significant gravitational waves are caused by the multi-step
phase transition. We show that the model can be tested by measuring the
characteristic spectra of the gravitational waves at future interferometers
such as LISA and DECIGO.Comment: 5 pages, 9 figures, contribution to the proceedings of Joint
Conference of ICGAC-XIII and IK15, Korea, 3--7 July 2017, based on
arXiv:1706.09721 [hep-ph
Higgs inflation in a radiative seesaw model
We investigate a simple model to explain inflation, neutrino masses and dark
matter simultaneously. This is based on the so-called radiative seesaw model
proposed by Ma in order to explain neutrino masses and dark matter by
introducing a -odd isospin doublet scalar field and -odd right-handed
neutrinos. We study the possibility that the Higgs boson as well as neutral
components of the -odd scalar doublet field can satisfy conditions from
slow-roll inflation and vacuum stability up to the inflation scale. We find
that a part of parameter regions where these scalar fields can play a role of
an inflaton is compatible with the current data from neutrino experiments and
those of the dark matter abundance as well as the direct search results. A
phenomenological consequence of this scenario results in a specific mass
spectrum of scalar bosons, which can be tested at the LHC, the International
Linear Collider and the Compact Linear Collider.Comment: 18 pages, 3 figure
Burrow Plasticity in the Deep-Sea Isopod Bathynomus doederleini (Crustacea: Isopoda: Cirolanidae)
We investigated whether the deep-sea isopod Bathynomus doederleini has the capacity to change burrow length in response to changes in environmental conditions. We observed burrowing behavior in individuals that were placed on substrates with either simple (ST) or complex (CT) surface topographies. Individuals in the ST group (N = 10) constructed seven burrows. The mean ratio of the burrow length to body length was 1.8. The individuals in the CT group ( N = 10) constructed eight burrows with a mean ratio of burrow length to body length of 2.5. Thus the burrows were significantly longer in the CT group. In addition, the isopods in the CT group often incorporated a chamber in the mid-section of the burrow. Our results may be used to infer the determinants of burrow morphology and speculate about the lifestyle of this species in the deep sea.ArticleZOOLOGICAL SCIENCE. 28(12):863-868 (2011)journal articl
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