Baryon asymmetry via leptogenesis in a neutrino mass model with complex scaling
Abstract
Baryogenesis via leptogenesis is investigated in a specific model of light neutrino masses and mixing angles. The latter was proposed on the basis of an assumed complexextended scaling property of the neutrino Majorana mass matrix M {sub ν}, derived with a type1 seesaw from a Dirac mass matrix m {sub D} and a heavy singlet neutrino Majorana mass matrix M {sub R} . One of its important features, highlighted here, is that there is a common source of the origin of a nonzero θ{sub 13} and the CP violating lepton asymmetry through the imaginary part of m {sub D} . The model predicted CP violation to be maximal for the Dirac type and vanishing for the Majorana type. We assume strongly hierarchical mass eigenvalues for M {sub R} . The leptonic CP asymmetry parameter ε{sup α}{sub 1} mm with lepton flavor α, originating from the decays of the lightest of the heavy neutrinos N {sub 1} (of mass M {sub 1}) at a temperature T ∼ M {sub 1}, is what matters here with the lepton asymmetries, originating from the decays of N {sub 2,3}, being washed out. The light leptonic and heavy neutrino number densities (normalized to the entropymore »
 Authors:

 Saha Institute of Nuclear Physics, HBNI, 1/AF Bidhannagar, Kolkata 700064 (India)
 Centre of Excellence in Theoretical and Mathematical Sciences, SOA University, Khandagiri Square, Bhubaneswar 751030 (India)
 Center for Astroparticle Physics and Space Science, Bose Institute, Kolkata 700091 (India)
 Publication Date:
 OSTI Identifier:
 22679980
 Resource Type:
 Journal Article
 Journal Name:
 Journal of Cosmology and Astroparticle Physics
 Additional Journal Information:
 Journal Volume: 2017; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 14757516
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ASYMMETRY; BARYONS; BOLTZMANN EQUATION; CP INVARIANCE; DENSITY; ENTROPY; FLAVOR MODEL; GEV RANGE; MAJORANA SPINORS; MASS; MIXING ANGLE; NEUTRINO OSCILLATION; NEUTRINOS; PARTICLE PRODUCTION; SENSITIVITY; UNIVERSE; VISIBLE RADIATION
Citation Formats
Samanta, Rome, Ghosal, Ambar, Chakraborty, Mainak, and Roy, Probir. Baryon asymmetry via leptogenesis in a neutrino mass model with complex scaling. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/03/025.
Samanta, Rome, Ghosal, Ambar, Chakraborty, Mainak, & Roy, Probir. Baryon asymmetry via leptogenesis in a neutrino mass model with complex scaling. United States. doi:10.1088/14757516/2017/03/025.
Samanta, Rome, Ghosal, Ambar, Chakraborty, Mainak, and Roy, Probir. Wed .
"Baryon asymmetry via leptogenesis in a neutrino mass model with complex scaling". United States. doi:10.1088/14757516/2017/03/025.
@article{osti_22679980,
title = {Baryon asymmetry via leptogenesis in a neutrino mass model with complex scaling},
author = {Samanta, Rome and Ghosal, Ambar and Chakraborty, Mainak and Roy, Probir},
abstractNote = {Baryogenesis via leptogenesis is investigated in a specific model of light neutrino masses and mixing angles. The latter was proposed on the basis of an assumed complexextended scaling property of the neutrino Majorana mass matrix M {sub ν}, derived with a type1 seesaw from a Dirac mass matrix m {sub D} and a heavy singlet neutrino Majorana mass matrix M {sub R} . One of its important features, highlighted here, is that there is a common source of the origin of a nonzero θ{sub 13} and the CP violating lepton asymmetry through the imaginary part of m {sub D} . The model predicted CP violation to be maximal for the Dirac type and vanishing for the Majorana type. We assume strongly hierarchical mass eigenvalues for M {sub R} . The leptonic CP asymmetry parameter ε{sup α}{sub 1} mm with lepton flavor α, originating from the decays of the lightest of the heavy neutrinos N {sub 1} (of mass M {sub 1}) at a temperature T ∼ M {sub 1}, is what matters here with the lepton asymmetries, originating from the decays of N {sub 2,3}, being washed out. The light leptonic and heavy neutrino number densities (normalized to the entropy density) are evolved via Boltzmann equations down to electroweak temperatures to yield a baryon asymmetry through sphaleronic transitions. The effects of flavored vs. unflavored leptogenesis in the three mass regimes (1) M {sub 1} < 10{sup 9} GeV, (2) 10{sup 9} GeV < M {sub 1} < 10{sup 12} GeV and (3) M {sub 1} > 10{sup 12} GeV are numerically worked out for both a normal and an inverted mass ordering of the light neutrinos. Corresponding results on the baryon asymmetry of the universe are obtained, displayed and discussed. For values close to the bestfit points of the input neutrino mass and mixing parameters, obtained from neutrino oscillation experiments, successful baryogenesis is achieved for the mass regime (2) and a normal mass ordering of the light neutrinos with a nonzero θ{sub 13} playing a crucial role. However, the other possibility of an inverted mass ordering for the same mass regime, though disfavored, cannot be excluded. A discussion is also given on the sensitivity of our result to the masses M {sub 2,3} of the heavier neutrinos N {sub 2,3}.},
doi = {10.1088/14757516/2017/03/025},
journal = {Journal of Cosmology and Astroparticle Physics},
issn = {14757516},
number = 03,
volume = 2017,
place = {United States},
year = {2017},
month = {3}
}