Gravitational searches for Lorentz violation with ultracold neutrons
Por:
Escobar, C. A., Martin-Ruiz, A.
Publicada:
30 abr 2019
Categoría:
Physics and astronomy (miscellaneous)
Resumen:
We investigate the consequences of Lorentz violation (as expressed
within the gravity sector of the Standard-Model Extension) for
gravitational quantum states of ultracold neutrons (UCNs). Since our
main aim is to compare our theoretical results with the recent
high-sensitivity GRANIT experiment, we frame this work according to the
laboratory conditions under which it was carried out. This offers the
possibility of testing Lorentz invariance by experiments using UCNs.
Thus we consider the nonrelativistic Hamiltonian describing the quantum
mechanics of an unpolarized neutron's beam in presence of a weak-gravity
field, and the latter is described by a post-Newtonian expansion of the
metric up to order O(2) and linear in the Lorentz-violating coefficients
(s) over bar (mu nu). Using a semiclassical wave packet, which is
appropriate to describe an intense beam of UCNs, we derive the effective
Hamiltonian describing the neutron's motion along the axis of free fall
and then we compute the Lorentz-violating shifts on the energy levels.
The comparison of our results with those obtained in the GRANIT
experiment leads to an upper bound for a particular combination of the
Lorentz-violating coefficients.
Filiaciones:
Escobar, C. A.:
Univ Nacl Autonoma Mexico, Inst Fis, Apartado Postal 20-364, Mexico City 01000, DF, Mexico
Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, Ciudad de México, 01000, Mexico
Martin-Ruiz, A.:
Univ Nacl Autonoma Mexico, Inst Ciencias Nucl, Mexico City 04510, DF, Mexico
Univ Nacl Autonoma Mexico, Ctr Ciencias Complejidad, Mexico City 04510, DF, Mexico
Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Ciudad de México, 04510, Mexico
Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Ciudad de México, 04510, Mexico
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