### Cosmological imprints of Dirac neutrinos in a keV-vacuum 2HDM

Shao-Ping Li (, Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, , Wuhan 430079, , China,) ; Xin-Qiang Li (, Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, , Wuhan 430079, , China,) ; Xin-Shuai Yan (, Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, , Wuhan 430079, , China,) ; Ya-Dong Yang (, Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, , Wuhan 430079, , China,)

The Dirac neutrino masses could be simply generated by a neutrinophilic scalar doublet with a vacuum being dramatically different from the electroweak one. While the case with an eV-scale vacuum has been widely explored previously, we exploit in this work the desert where the scalar vacuum is of $\mathcal{O}(\mathrm{keV})$ scale. In this regime, there would be rare hope to probe the keV-vacuum neutrinophilic scalar model via the lepton-flavor-violating processes, which makes it distinguishable from the widely considered eV-scale vacuum. Although such a keV-vacuum scenario is inert in the low-energy flavor physics, we show that the baryogenesis realized via the lightest Dirac neutrino can be a natural candidate in explaining the baryon asymmetry of the Universe. Furthermore, the Dirac neutrinos with a keV-vacuum scalar can generate a shift of the effective neutrino number within the range $\mathcal{O}(\mathrm{keV})$ , which can be probed by the future Simons Observatory experiments. In particular, the model with a minimal value $\mathcal{O}(\mathrm{keV})$ can already be falsified by the future CMB Stage-IV and Large Scale Structure surveys, providing consequently striking exploratory avenues in the cosmological regime for such a keV-vacuum scenario.

{
"_oai": {
"updated": "2023-03-08T03:30:23Z",
"id": "oai:repo.scoap3.org:76249",
"sets": [
"CPC"
]
},
"authors": [
{
"affiliations": [
{
"country": "China",
"value": ", Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, , Wuhan 430079, , China,"
}
],
"surname": "Li",
"email": "ShowpingLee@mails.ccnu.edu.cn",
"full_name": "Li, Shao-Ping",
"given_names": "Shao-Ping"
},
{
"affiliations": [
{
"country": "China",
"value": ", Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, , Wuhan 430079, , China,"
}
],
"surname": "Li",
"email": "xqli@mail.ccnu.edu.cn(Corresponding author)",
"full_name": "Li, Xin-Qiang",
"given_names": "Xin-Qiang"
},
{
"affiliations": [
{
"country": "China",
"value": ", Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, , Wuhan 430079, , China,"
}
],
"surname": "Yan",
"email": "xinshuai@mail.ccnu.edu.cn",
"full_name": "Yan, Xin-Shuai",
"given_names": "Xin-Shuai"
},
{
"affiliations": [
{
"country": "China",
"value": ", Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, , Wuhan 430079, , China,"
}
],
"surname": "Yang",
"email": "yangyd@mail.ccnu.edu.cn",
"full_name": "Yang, Ya-Dong",
"given_names": "Ya-Dong"
}
],
"titles": [
{
"source": "IOP",
"title": "Cosmological imprints of Dirac neutrinos in a keV-vacuum 2HDM  "
}
],
"dois": [
{
"value": "10.1088/1674-1137/acb6de"
}
],
"publication_info": [
{
"journal_title": "Chinese Physics C",
"material": "article",
"journal_volume": "47",
"artid": "043109",
"year": 2023,
"journal_issue": "4"
}
],
"$schema": "http://repo.scoap3.org/schemas/hep.json", "acquisition_source": { "date": "2023-03-08T03:30:21.543732", "source": "IOP", "method": "IOP", "submission_number": "817bae1ebd6111eda920065bd8dc6b20" }, "page_nr": [ 12 ], "license": [ { "url": "Creative Commons Attribution 3.0 licence" } ], "copyright": [ { "statement": "\u00a9 2023 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd", "year": "2023" } ], "control_number": "76249", "record_creation_date": "2023-03-08T03:30:21.543757", "_files": [ { "checksum": "md5:02bb0fcbd40fbfc434c01ae378e35f5c", "filetype": "xml", "bucket": "c8df3d90-7d5e-4d28-a170-3261699b0886", "version_id": "fb0788f4-dea7-45d2-9572-0bfb24605907", "key": "10.1088/1674-1137/acb6de.xml", "size": 217069 }, { "checksum": "md5:b4c084135965d52715467aee4f93687d", "filetype": "pdf", "bucket": "c8df3d90-7d5e-4d28-a170-3261699b0886", "version_id": "98d5cefd-a1bd-4991-b043-d9f0cbe938a1", "key": "10.1088/1674-1137/acb6de.pdf", "size": 1241622 } ], "collections": [ { "primary": "Chinese Physics C" } ], "arxiv_eprints": [ { "categories": [ "hep-ph" ], "value": "2202.10250" } ], "abstracts": [ { "source": "IOP", "value": "The Dirac neutrino masses could be simply generated by a neutrinophilic scalar doublet with a vacuum being dramatically different from the electroweak one. While the case with an eV-scale vacuum has been widely explored previously, we exploit in this work the desert where the scalar vacuum is of$\\mathcal{O}(\\mathrm{keV})$scale. In this regime, there would be rare hope to probe the keV-vacuum neutrinophilic scalar model via the lepton-flavor-violating processes, which makes it distinguishable from the widely considered eV-scale vacuum. Although such a keV-vacuum scenario is inert in the low-energy flavor physics, we show that the baryogenesis realized via the lightest Dirac neutrino can be a natural candidate in explaining the baryon asymmetry of the Universe. Furthermore, the Dirac neutrinos with a keV-vacuum scalar can generate a shift of the effective neutrino number within the range$\\mathcal{O}(\\mathrm{keV})$, which can be probed by the future Simons Observatory experiments. In particular, the model with a minimal value$\\mathcal{O}(\\mathrm{keV})\$   can already be falsified by the future CMB Stage-IV and Large Scale Structure surveys, providing consequently striking exploratory avenues in the cosmological regime for such a keV-vacuum scenario."
}
],
"imprints": [
{
"date": "2023-04-01",
"publisher": "IOP"
}
]
}
Published on:
01 April 2023
Publisher:
IOP
Published in:
Chinese Physics C , Volume 47 (2023)
Issue 4
Article ID: 043109
DOI:
https://doi.org/10.1088/1674-1137/acb6de
arXiv:
2202.10250