Based on an integrated luminosity of 1.61 fb −1 e + e − collision data collected with the KLOE detector at DAΦNE, the Frascati ϕ-factory, a search for the P- and CP-violating decay η → π + π − has been performed. Radiative ϕ → ηγ decay is exploited to access the η mesons. No signal is observed in the π + π − invariant mass spectrum, and the upper limit on the branching fraction at 90% confidence level is determined to be ℬ(η → π + π − ) < 4.9 × 10 −6, which is approximately three times smaller than the previous KLOE result. From the combination of these two measurements we get ℬ(η → π + π − ) < 4.4 × 10 −6 at 90% confidence level.
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"value": "Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden",
"organization": "Uppsala University"
}
],
"surname": "Wolke",
"given_names": "M.",
"full_name": "Wolke, M."
}
],
"titles": [
{
"source": "Springer",
"title": "Upper limit on the \u03b7 \u2192 \u03c0 + \u03c0 \u2212 branching fraction with the KLOE experiment"
}
],
"dois": [
{
"value": "10.1007/JHEP10(2020)047"
}
],
"publication_info": [
{
"page_end": "11",
"journal_title": "Journal of High Energy Physics",
"material": "article",
"journal_volume": "2020",
"artid": "JHEP10(2020)047",
"year": 2020,
"page_start": "1",
"journal_issue": "10"
}
],
"$schema": "http://repo.scoap3.org/schemas/hep.json",
"acquisition_source": {
"date": "2021-01-24T01:31:48.891731",
"source": "Springer",
"method": "Springer",
"submission_number": "4afd0abe5ddb11ebbd0e02163e01809a"
},
"page_nr": [
11
],
"license": [
{
"url": "https://creativecommons.org/licenses//by/4.0",
"license": "CC-BY-4.0"
}
],
"copyright": [
{
"holder": "The Author(s)",
"year": "2020"
}
],
"control_number": "59596",
"collaborations": [
{
"value": "The KLOE-2 collaboration"
}
],
"record_creation_date": "2021-01-24T01:31:48.891775",
"collections": [
{
"primary": "Journal of High Energy Physics"
}
],
"arxiv_eprints": [
{
"categories": [
"hep-ex"
],
"value": "2006.14710"
}
],
"abstracts": [
{
"source": "Springer",
"value": "Based on an integrated luminosity of 1.61 fb \u22121 e + e \u2212 collision data collected with the KLOE detector at DA\u03a6NE, the Frascati \u03d5-factory, a search for the P- and CP-violating decay \u03b7 \u2192 \u03c0 + \u03c0 \u2212 has been performed. Radiative \u03d5 \u2192 \u03b7\u03b3 decay is exploited to access the \u03b7 mesons. No signal is observed in the \u03c0 + \u03c0 \u2212 invariant mass spectrum, and the upper limit on the branching fraction at 90% confidence level is determined to be \u212c(\u03b7 \u2192 \u03c0 + \u03c0 \u2212 ) < 4.9 \u00d7 10 \u22126, which is approximately three times smaller than the previous KLOE result. From the combination of these two measurements we get \u212c(\u03b7 \u2192 \u03c0 + \u03c0 \u2212 ) < 4.4 \u00d7 10 \u22126 at 90% confidence level."
}
],
"imprints": [
{
"date": "2020-10-07",
"publisher": "Springer"
}
]
}