Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Constraints on light scalars from PS191 results   We argue that the fixed target experiment PS191 operating on a proton beam of
19.2 GeV at CERN in the eighties was sensitive to hypothetical light scalars
produced by mesons and decaying to charged particles. The experiment was
dedicated to searches for sterile neutrinos produced in weak meson decays and
decaying into final states with pairs of charged particles: electrons and
muons. Two charged tracks from the same point have been adopted as the signal
signature. Exploiting the same signature we use the negative results of
searches at PS191 and place new limits on the light scalars coupled to the
Standard Model (SM) particles via mixing with the Higgs boson. In particular,
previously allowed region of masses 100--150 MeV and mixing above 4$\times
10^{-4}$ is disfavored. Our analysis can be extended straightforwardly to
models with other patterns of scalar couplings to SM particles.

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The categories of this paper are: eess
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
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The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
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The categories of this paper are: q-alg
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The categories of this paper are: nlin
13
The categories of this paper are: quant-ph