Abstract
A search is reported for a light pseudoscalar Higgs boson decaying to a pair of tau leptons, produced in association with a b b-bar pair, in the context of two-Higgs-doublet models. The results are based on pp collision data at a centre-of-mass energy of 8 TeV collected by the CMS experiment at the LHC and corresponding to an integrated luminosity of 19.7 inverse femtobarns. Pseudoscalar boson masses between 25 and 80 GeV are probed. No evidence for a pseudoscalar boson is found and upper limits are set on the production cross section times branching fraction to tau pairs between 7 and 39 pb at the 95% confidence level. This excludes pseudoscalar A bosons with masses between 25 and 80 GeV, with standard model-like Higgs boson negative couplings to down-type fermions, produced in association with b b-bar pairs, in Type-II, two-Higgs-doublet models.
Highlights
The discovery of a new boson with a mass close to 125 GeV [1,2,3], consistent with the standard model (SM) Higgs boson, has shed light on one of the most important questions of physics: the origin of the mass of elementary particles
No evidence for a pseudoscalar boson is found and upper limits are set on the product of cross section and branching fraction to τ pairs between 7 and 39 pb at the 95% confidence level
Jets identified as originating from a b quark, called b-tagged jets, are identified using the combined secondary vertex (CSV) algorithm [44], which is based on a likelihood technique, and exploits information such as the impact parameters of charged-particle tracks and the properties of reconstructed decay vertices
Summary
The discovery of a new boson with a mass close to 125 GeV [1,2,3], consistent with the standard model (SM) Higgs boson, has shed light on one of the most important questions of physics: the origin of the mass of elementary particles. Higgs boson total width measurements and branching fractions even if one or more of the light Higgs bosons have a mass below half of 125 GeV provided one adjusts the model parameters so that the branching fraction of the SM Higgs boson to pairs of light Higgs bosons is very small This scenario can be tested at the CERN LHC by searching for singly produced light bosons decaying to a pair of τ leptons with large cross sections. In Type II 2HDMs, if the Higgs coupling to the third generation of quarks is enhanced, as happens at large tan β, a large production cross section is expected for the production of the low-mass A boson in association with bb. This letter presents a search for a low-mass pseudoscalar Higgs boson produced in association with a bb pair and decaying to a pair of τ leptons. The invariant mass distributions of the τ pairs in all three channels are used to search for pseudoscalar bosons with masses between 25 and 80 GeV
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
