Accidental PecceiQuinn Symmetry Protected to Arbitrary Order
Abstract
A S U (N )_{L}×S U (N )_{R} gauge theory for a scalar multiplet Y transforming in the bifundamental representation (N ,N ¯) preserves, for N >4 , an accidental U (1 ) symmetry first broken at operator dimension N . A vacuum expectation value for Y can break the symmetry to H_{s}=S U (N )L_{+R} or to H_{h}=S U (N 1 )_{L}×S U (N 1 )_{R}×U (1 )_{L +R} . In the first case the accidental U (1 ) gets also broken, yielding a pseudoNambuGoldstone boson with mass suppression controlled by N . In the second case a global U (1 ) remains unbroken. The strong C P problem is solved by coupling Y to new fermions carrying color. The first case allows for a PecceiQuinn solution with U (1 )P_{Q} protected by the gauge symmetry up to order N . In the second case U (1 ) can get broken by condensates of the new strong dynamics, resulting in a composite axion. By coupling Y to fermions carrying only weak isospin, models for axionlike particles can be constructed.
 Publication:

Physical Review Letters
 Pub Date:
 July 2017
 DOI:
 10.1103/PhysRevLett.119.011801
 arXiv:
 arXiv:1704.01122
 Bibcode:
 2017PhRvL.119a1801D
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 6 pages 1 figure