Type-II seesaws at colliders, lepton asymmetry and singlet scalar dark matter

Journal Article · Tue Apr 15 04:00:00 EDT 2008 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2008/04/037· OSTI ID:22137862

McDonald, John; Sahu, Narendra ^[1]; Sarkar, Utpal ^[2]

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1. Cosmology and Astroparticle Physics Group, University of Lancaster, Lancaster LA1 4YB (United Kingdom)
2. Theory Division, Physical Research Laboratory, Navarangpura, Ahmedabad, 380 009 (India)

We propose an extension of the standard model with a B-L global symmetry that is broken softly at the TeV scale. The neutrinos acquire masses through a type-II seesaw while the lepton (L) asymmetry arises in the singlet sector but without B-L-number violation. The model has the virtue that the scale of L-number violation ({Lambda}) giving rise to neutrino masses is independent of the scale of leptogenesis ({Lambda}'). As a result the model can explain neutrino masses, singlet scalar dark matter and leptogenesis at the TeV scale. The stability of the dark matter is ensured by a surviving Z{sub 2} symmetry, which could be lifted at the Planck scale, thereby allowing Planck scale suppressed decay of singlet scalar dark matter particles of mass Almost-Equal-To 3 MeV to e{sup +}e{sup -} pairs in the Galactic halo. The model also predicts a few hundred GeV doubly charged scalar and a long-lived charged fermion, whose decay can be studied at the Large Hadron Collider (LHC) and International Linear Collider (ILC)

• OSTI ID: 22137862
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 04 Vol. 2008; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
79 ASTRONOMY AND ASTROPHYSICS
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PARTICLE PRODUCTION
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SCALARS
STANDARD MODEL
SYMMETRY BREAKING
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