We study the inclusive and exclusive cross sections of $$e^+e^-\rightarrow \text {hadrons}$$ for center-of-mass energies between 3.70 and $$3.83\,\,\textrm{GeV} $$ to infer the mass, width, and couplings of the $$\psi (3770)$$ resonance. By using a coupled-channel K-matrix approach, we setup our analysis to respect unitarity and the analyticity properties of the underlying scattering amplitudes. We fit several models to the full dataset and identify our nominal results through a statistical model comparison. We find that, accounting for the interplay between the $$\psi (2S)$$ and the $$\psi (3770)$$ , no further pole is required to describe the $$\psi (3770)$$ line shape. In particular we derive from the pole location $$M_{\psi (3770)}~=~3778.8~\pm ~0.3~\,\textrm{MeV} $$ and $$\varGamma _{\psi (3770)}~=~25.0~\pm ~0.5~\,\textrm{MeV} $$ . Moreover, we find the decay to $$D^+D^-$$ and $$D^0\bar{D}^0$$ to be consistent with isospin symmetry and derive an upper bound on the branching ratio $${\mathcal {B}}(\psi (3770) \rightarrow \text {non-}D\bar{D}) < 6\%$$ at $$90\%$$ probability.
{ "_oai": { "updated": "2024-06-18T00:32:00Z", "id": "oai:repo.scoap3.org:85296", "sets": [ "EPJC" ] }, "authors": [ { "affiliations": [ { "country": "Germany", "value": "Institute for Advanced Simulation and Institut f\u00fcr Kernphysik, Forschungszentrum J\u00fclich, J\u00fclich, 52425, Germany", "organization": "Institute for Advanced Simulation and Institut f\u00fcr Kernphysik, Forschungszentrum J\u00fclich" } ], "surname": "Hanhart", "given_names": "Christoph", "full_name": "Hanhart, Christoph" }, { "affiliations": [ { "country": "Germany", "value": "Physik Department T31, Technische Universit\u00e4t M\u00fcnchen, Garching, 85748, Germany", "organization": "Technische Universit\u00e4t M\u00fcnchen" }, { "country": "Germany", "value": "Helmholtz-Institut f\u00fcr Strahlen- und Kernphysik (Theorie), Bethe Center for Theoretical Physics, Universit\u00e4t Bonn, Bonn, 53115, Germany", "organization": "Universit\u00e4t Bonn" } ], "surname": "K\u00fcrten", "given_names": "Stephan", "full_name": "K\u00fcrten, Stephan" }, { "affiliations": [ { "country": "Germany", "value": "Theoretische Physik 1, Naturwissenschaftlich-Technische Fakult\u00e4t, Universit\u00e4t Siegen, Siegen, 57068, Germany", "organization": "Universit\u00e4t Siegen" } ], "surname": "Reboud", "email": "merilreboud@gmail.com", "full_name": "Reboud, M\u00e9ril", "given_names": "M\u00e9ril" }, { "affiliations": [ { "country": "UK", "value": "Institute for Particle Physics Phenomenology and Department of Physics, Durham University, DH1 3LE, Durham, UK", "organization": "Durham University" } ], "surname": "Dyk", "given_names": "Danny", "full_name": "Dyk, Danny" } ], "titles": [ { "source": "Springer", "title": "Analysis of the $${\\psi (3770)}$$ <math> <mrow> <mi>\u03c8</mi> <mo>(</mo> <mn>3770</mn> <mo>)</mo> </mrow> </math> resonance in line with unitarity and analyticity constraints" } ], "dois": [ { "value": "10.1140/epjc/s10052-024-12785-8" } ], "publication_info": [ { "page_end": "12", "journal_title": "European Physical Journal C", "material": "article", "journal_volume": "84", "artid": "s10052-024-12785-8", "year": 2024, "page_start": "1", "journal_issue": "5" } ], "$schema": "http://repo.scoap3.org/schemas/hep.json", "acquisition_source": { "date": "2024-06-18T00:31:10.856477", "source": "Springer", "method": "Springer", "submission_number": "e58fdc7c2d0911ef9fecbe60ec5a7b90" }, "page_nr": [ 12 ], "license": [ { "url": "https://creativecommons.org/licenses//by/4.0", "license": "CC-BY-4.0" } ], "copyright": [ { "holder": "The Author(s)", "year": "2024" } ], "control_number": "85296", "record_creation_date": "2024-05-09T15:30:11.660901", "_files": [ { "checksum": "md5:466f74caef5cca88bf7acb62204eae96", "filetype": "xml", "bucket": "b634dc61-637b-4396-b4af-8d9116d3c4f3", "version_id": "5c9aa44d-90a7-46c2-9da4-b595ff746d3a", "key": "10.1140/epjc/s10052-024-12785-8.xml", "size": 27800 }, { "checksum": "md5:41d463f96445775d6f232638b9fe570e", "filetype": "pdf/a", "bucket": "b634dc61-637b-4396-b4af-8d9116d3c4f3", "version_id": "7d11f289-2e02-42fa-a751-62f96556fc46", "key": "10.1140/epjc/s10052-024-12785-8_a.pdf", "size": 683364 } ], "collections": [ { "primary": "European Physical Journal C" } ], "arxiv_eprints": [ { "categories": [ "hep-ph", "hep-ex" ], "value": "2312.00619" } ], "abstracts": [ { "source": "Springer", "value": "We study the inclusive and exclusive cross sections of $$e^+e^-\\rightarrow \\text {hadrons}$$ <math> <mrow> <msup> <mi>e</mi> <mo>+</mo> </msup> <msup> <mi>e</mi> <mo>-</mo> </msup> <mo>\u2192</mo> <mtext>hadrons</mtext> </mrow> </math> for center-of-mass energies between 3.70 and $$3.83\\,\\,\\textrm{GeV} $$ <math> <mrow> <mn>3.83</mn> <mspace width=\"0.166667em\"></mspace> <mspace width=\"0.166667em\"></mspace> <mtext>GeV</mtext> </mrow> </math> to infer the mass, width, and couplings of the $$\\psi (3770)$$ <math> <mrow> <mi>\u03c8</mi> <mo>(</mo> <mn>3770</mn> <mo>)</mo> </mrow> </math> resonance. By using a coupled-channel K-matrix approach, we setup our analysis to respect unitarity and the analyticity properties of the underlying scattering amplitudes. We fit several models to the full dataset and identify our nominal results through a statistical model comparison. We find that, accounting for the interplay between the $$\\psi (2S)$$ <math> <mrow> <mi>\u03c8</mi> <mo>(</mo> <mn>2</mn> <mi>S</mi> <mo>)</mo> </mrow> </math> and the $$\\psi (3770)$$ <math> <mrow> <mi>\u03c8</mi> <mo>(</mo> <mn>3770</mn> <mo>)</mo> </mrow> </math> , no further pole is required to describe the $$\\psi (3770)$$ <math> <mrow> <mi>\u03c8</mi> <mo>(</mo> <mn>3770</mn> <mo>)</mo> </mrow> </math> line shape. In particular we derive from the pole location $$M_{\\psi (3770)}~=~3778.8~\\pm ~0.3~\\,\\textrm{MeV} $$ <math> <mrow> <msub> <mi>M</mi> <mrow> <mi>\u03c8</mi> <mo>(</mo> <mn>3770</mn> <mo>)</mo> </mrow> </msub> <mspace width=\"3.33333pt\"></mspace> <mo>=</mo> <mspace width=\"3.33333pt\"></mspace> <mn>3778.8</mn> <mspace width=\"3.33333pt\"></mspace> <mo>\u00b1</mo> <mspace width=\"3.33333pt\"></mspace> <mn>0.3</mn> <mspace width=\"3.33333pt\"></mspace> <mspace width=\"0.166667em\"></mspace> <mtext>MeV</mtext> </mrow> </math> and $$\\varGamma _{\\psi (3770)}~=~25.0~\\pm ~0.5~\\,\\textrm{MeV} $$ <math> <mrow> <msub> <mi>\u0393</mi> <mrow> <mi>\u03c8</mi> <mo>(</mo> <mn>3770</mn> <mo>)</mo> </mrow> </msub> <mspace width=\"3.33333pt\"></mspace> <mo>=</mo> <mspace width=\"3.33333pt\"></mspace> <mn>25.0</mn> <mspace width=\"3.33333pt\"></mspace> <mo>\u00b1</mo> <mspace width=\"3.33333pt\"></mspace> <mn>0.5</mn> <mspace width=\"3.33333pt\"></mspace> <mspace width=\"0.166667em\"></mspace> <mtext>MeV</mtext> </mrow> </math> . Moreover, we find the decay to $$D^+D^-$$ <math> <mrow> <msup> <mi>D</mi> <mo>+</mo> </msup> <msup> <mi>D</mi> <mo>-</mo> </msup> </mrow> </math> and $$D^0\\bar{D}^0$$ <math> <mrow> <msup> <mi>D</mi> <mn>0</mn> </msup> <msup> <mrow> <mover> <mrow> <mi>D</mi> </mrow> <mrow> <mo>\u00af</mo> </mrow> </mover> </mrow> <mn>0</mn> </msup> </mrow> </math> to be consistent with isospin symmetry and derive an upper bound on the branching ratio $${\\mathcal {B}}(\\psi (3770) \\rightarrow \\text {non-}D\\bar{D}) < 6\\%$$ <math> <mrow> <mi>B</mi> <mo>(</mo> <mi>\u03c8</mi> <mo>(</mo> <mn>3770</mn> <mo>)</mo> <mo>\u2192</mo> <mtext>non-</mtext> <mi>D</mi> <mover> <mrow> <mi>D</mi> </mrow> <mrow> <mo>\u00af</mo> </mrow> </mover> <mo>)</mo> <mo><</mo> <mn>6</mn> <mo>%</mo> </mrow> </math> at $$90\\%$$ <math> <mrow> <mn>90</mn> <mo>%</mo> </mrow> </math> probability." } ], "imprints": [ { "date": "2024-05-09", "publisher": "Springer" } ] }