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Title: Low-energy neutrino Majorana phases and charged-lepton electric dipole moments

Abstract

If the neutrinos are Majorana fermions, there are at least three new, potentially observable CP-odd phases that parametrize CP-invariance violating phenomena. We currently have no information regarding any of them and know that two out of the three, the so-called Majorana phases, are very hard to access experimentally. Here, we discuss the effect of Majorana phases on charged-lepton electric dipole moments (EDM), and explicitly show that neutrino Majorana phases induce EDMs even in the absence of other sources of CP-invariance violation. We also argue that while the Majorana neutrino contribution to EDMs is tiny, there is one generic ultraviolet completion to the standard model plus massive Majorana neutrinos - the standard model plus a triplet Higgs boson - that leads to significantly enhanced contributions which are still proportional to the low-energy neutrino Majorana phases. If this particular scenario is realized in nature, it seems possible, at least in principle, to measure the Majorana phases by precisely measuring charged-lepton EDMs.

Authors:
;  [1]
  1. Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208 (United States)
Publication Date:
OSTI Identifier:
20713814
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 72; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevD.72.093008; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CP INVARIANCE; ELECTRIC DIPOLE MOMENTS; HIGGS BOSONS; NEUTRINOS; REST MASS; STANDARD MODEL; TRIPLETS; ULTRAVIOLET RADIATION

Citation Formats

Gouvea, Andre de, and Gopalakrishna, Shrihari. Low-energy neutrino Majorana phases and charged-lepton electric dipole moments. United States: N. p., 2005. Web. doi:10.1103/PhysRevD.72.093008.
Gouvea, Andre de, & Gopalakrishna, Shrihari. Low-energy neutrino Majorana phases and charged-lepton electric dipole moments. United States. doi:10.1103/PhysRevD.72.093008.
Gouvea, Andre de, and Gopalakrishna, Shrihari. Tue . "Low-energy neutrino Majorana phases and charged-lepton electric dipole moments". United States. doi:10.1103/PhysRevD.72.093008.
@article{osti_20713814,
title = {Low-energy neutrino Majorana phases and charged-lepton electric dipole moments},
author = {Gouvea, Andre de and Gopalakrishna, Shrihari},
abstractNote = {If the neutrinos are Majorana fermions, there are at least three new, potentially observable CP-odd phases that parametrize CP-invariance violating phenomena. We currently have no information regarding any of them and know that two out of the three, the so-called Majorana phases, are very hard to access experimentally. Here, we discuss the effect of Majorana phases on charged-lepton electric dipole moments (EDM), and explicitly show that neutrino Majorana phases induce EDMs even in the absence of other sources of CP-invariance violation. We also argue that while the Majorana neutrino contribution to EDMs is tiny, there is one generic ultraviolet completion to the standard model plus massive Majorana neutrinos - the standard model plus a triplet Higgs boson - that leads to significantly enhanced contributions which are still proportional to the low-energy neutrino Majorana phases. If this particular scenario is realized in nature, it seems possible, at least in principle, to measure the Majorana phases by precisely measuring charged-lepton EDMs.},
doi = {10.1103/PhysRevD.72.093008},
journal = {Physical Review. D, Particles Fields},
number = 9,
volume = 72,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}
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