Search for long-lived particles decaying to $e^\pm \mu^\mp \nu$

Aaij, R.; Beteta, C. Abellán; Ackernley, T.; Adeva, B.; Adinolfi, M.; Afsharnia, H.; Aidala, C.A.; Aiola, S.; Ajaltouni, Z.; Akar, S.

doi:10.1140/epjc/s10052-021-08994-0

Search for long-lived particles decaying to $e^\pm \mu^\mp \nu$

LHCb

Collaboration

Dec 4, 2020

16 pages

Published in:

Eur.Phys.J.C 81 (2021) 3, 261

Published: Mar 26, 2021

e-Print:

2012.02696 [hep-ex]

DOI:

10.1140/epjc/s10052-021-08994-0

PDG: Long-Lived Particle (LLP) Search at Hadron Collisions

Report number:

LHCb-PAPER-2020-027,
CERN-EP-2020-212

Experiments:

CERN-LHC-LHCb

View in:

reference search24 citations

Citations per year

Abstract: (Springer)

Long-lived particles decaying to

{e ^\pm } {\mu ^\mp } {\nu }

, with masses between 7 and

50 \,\text {GeV/}c^2

and lifetimes between 2 and

50 \,\text {ps}

, are searched for by looking at displaced vertices containing electrons and muons of opposite charges. The search is performed using

5.4 \,\text {fb} ^{-1}

of

p p

collisions collected with the LHCb detector at a centre-of-mass energy of

\sqrt{s} = 13 \,\text {TeV}

. Three mechanisms of production of long-lived particles are considered: the direct pair production from quark interactions, the pair production from the decay of a Standard-Model-like Higgs boson with a mass of

125 \,\text {GeV/}c^2

, and the charged current production from an on-shell

W

boson with an additional lepton. No evidence of these long-lived states is obtained and upper limits on the production cross-section times branching fraction are set on the different production modes.

Note:

All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2020-027.html (LHCb public pages)

p p: colliding beams
neutral particle: long-lived
quark: interaction
p p: scattering
neutral particle: pair production
charged current
channel cross section: branching ratio: upper limit
Higgs particle: decay modes
electron
neutral particle: mass

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