In this paper, a detailed study to probe the top quark Flavour-Changing Neutral Currents (FCNC) tqγ and tqZ at the future eâe+ collider FCC-ee in two different center-of-mass energies of 240 and 350 GeV is presented. A set of useful variables are proposed and used in a multivariate technique to separate signal eâe+âZ/γâtq¯ (t¯q) from Standard Model background processes. The study includes a fast detector simulation based on the delphes package to consider the detector effects. The upper limits on the FCNC branching ratios at 95% confidence level (CL) in terms of the integrated luminosity are presented. It is shown that with 300 fbâ1 of integrated luminosity of data, FCC-ee would be able to exclude the effective coupling strengths above O(10â4â10â5) which is corresponding to branching fraction of O(0.01â0.001) %. We show that moving to a high-luminosity regime leads to a significant improvement on the upper bounds on the top quark FCNC couplings to a photon or a Z boson.
{ "license": [ { "url": "http://creativecommons.org/licenses/by/3.0/", "license": "CC-BY-3.0" } ], "copyright": [ { "statement": "The Author(s)" } ], "control_number": "22052", "_oai": { "updated": "2018-04-18T13:01:21Z", "id": "oai:repo.scoap3.org:22052", "sets": [ "PLB" ] }, "authors": [ { "surname": "Khanpour", "given_names": "Hamzeh", "raw_name": "Khanpour, Hamzeh", "affiliations": [ { "country": "Iran", "value": "Department of Physics, University of Science and Technology of Mazandaran, P.O. Box 48518-78195, Behshahr, Iran" }, { "country": "Iran", "value": "School of Particles and Accelerators, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran, Iran" } ], "full_name": "Khanpour, Hamzeh", "orcid": "0000-0001-7078-7177" }, { "raw_name": "Khatibi, Sara", "affiliations": [ { "country": "Iran", "value": "School of Particles and Accelerators, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran, Iran" } ], "surname": "Khatibi", "given_names": "Sara", "full_name": "Khatibi, Sara" }, { "raw_name": "Yanehsari, Morteza Khatiri", "affiliations": [ { "country": "Iran", "value": "School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran, Iran" } ], "surname": "Yanehsari", "given_names": "Morteza Khatiri", "full_name": "Yanehsari, Morteza Khatiri" }, { "raw_name": "Najafabadi, Mojtaba Mohammadi", "affiliations": [ { "country": "Iran", "value": "School of Particles and Accelerators, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran, Iran" } ], "surname": "Najafabadi", "given_names": "Mojtaba Mohammadi", "full_name": "Najafabadi, Mojtaba Mohammadi" } ], "_files": [ { "checksum": "md5:9fb1c6a0d0bf662e9c76e404d376a9fd", "filetype": "xml", "bucket": "06c888dc-9dae-4d0b-bc68-3c76d099a855", "version_id": "a3ce6bf7-3448-483a-9ead-542241416944", "key": "10.1016/j.physletb.2017.10.047.xml", "size": 204180 }, { "checksum": "md5:c0997efa4e5b4786a1ca34b9d7fbe467", "filetype": "pdf", "bucket": "06c888dc-9dae-4d0b-bc68-3c76d099a855", "version_id": "89f7106b-91db-4e5c-b52d-1cb3d8865a4c", "key": "10.1016/j.physletb.2017.10.047.pdf", "size": 950006 }, { "checksum": "md5:015ff72ed598e4841b2ed9c125654c2d", "filetype": "pdf/a", "bucket": "06c888dc-9dae-4d0b-bc68-3c76d099a855", "version_id": "1a2afb66-7977-405a-a349-56c6b3a63e04", "key": "10.1016/j.physletb.2017.10.047_a.pdf", "size": 1283771 } ], "record_creation_date": "2017-10-25T00:00:00", "titles": [ { "source": "Elsevier", "title": "Single top quark production as a probe of anomalous tq\u03b3 and tqZ couplings at the FCC-ee" } ], "dois": [ { "value": "10.1016/j.physletb.2017.10.047" } ], "publication_info": [ { "journal_title": "Physics Letters B", "material": "article", "year": 2017 } ], "$schema": "http://repo.scoap3.org/schemas/hep.json", "abstracts": [ { "source": "Elsevier", "value": "In this paper, a detailed study to probe the top quark Flavour-Changing Neutral Currents (FCNC) tq\u00ce\u00b3 and tqZ at the future e\u00e2\u0088\u0092e+ collider FCC-ee in two different center-of-mass energies of 240 and 350 GeV is presented. A set of useful variables are proposed and used in a multivariate technique to separate signal e\u00e2\u0088\u0092e+\u00e2\u0086\u0092Z/\u00ce\u00b3\u00e2\u0086\u0092tq\u00c2\u00af\u00c2 (t\u00c2\u00afq) from Standard Model background processes. The study includes a fast detector simulation based on the delphes package to consider the detector effects. The upper limits on the FCNC branching ratios at 95% confidence level (CL) in terms of the integrated luminosity are presented. It is shown that with 300\u00c2 fb\u00e2\u0088\u00921 of integrated luminosity of data, FCC-ee would be able to exclude the effective coupling strengths above O(10\u00e2\u0088\u00924\u00e2\u0088\u009210\u00e2\u0088\u00925) which is corresponding to branching fraction of O(0.01\u00e2\u0088\u00920.001) %. We show that moving to a high-luminosity regime leads to a significant improvement on the upper bounds on the top quark FCNC couplings to a photon or a Z boson." } ], "imprints": [ { "date": "2017-10-27", "publisher": "Elsevier" } ], "acquisition_source": { "date": "2017-10-25T00:00:00", "source": "Elsevier", "method": "scoap3", "submission_number": "372790d4430511e898b102163e01809a" } }