{"work":{"id":"8034855c-344f-4318-b073-e7b48263c760","openalex_id":null,"doi":null,"arxiv_id":"1205.2228","raw_key":null,"title":"Precise Measurement of the e+ e- --> pi+ pi- (gamma) Cross Section with the Initial-State Radiation Method at BABAR","authors":null,"authors_text":"BaBar, J","year":2012,"venue":"hep-ex","abstract":"A precise measurement of the cross section of the process $e^+e^-\\to\\pi^+\\pi^-(\\gamma)$ from threshold to an energy of 3GeV is obtained with the initial-state radiation (ISR) method using 232fb$^{-1}$ of data collected with the BaBar detector at $e^+e^-$ center-of-mass energies near 10.6GeV. The ISR luminosity is determined from a study of the leptonic process $e^+e^-\\to\\mu^+\\mu^-(\\gamma)\\gamma_{\\rm ISR}$, which is found to agree with the next-to-leading-order QED prediction to within 1.1%. The cross section for the process $e^+e^-\\to\\pi^+\\pi^-(\\gamma)$ is obtained with a systematic uncertainty of 0.5% in the dominant $\\rho$ resonance region. The leading-order hadronic contribution to the muon magnetic anomaly calculated using the measured $\\pi\\pi$ cross section from threshold to 1.8GeV is $(514.1 \\pm 2.2({\\rm stat}) \\pm 3.1({\\rm syst}))\\times 10^{-10}$.","external_url":"https://arxiv.org/abs/1205.2228","cited_by_count":null,"metadata_source":"pith","metadata_fetched_at":"2026-07-09T03:55:55.174192+00:00","pith_arxiv_id":"1205.2228","created_at":"2026-05-11T22:41:21.951132+00:00","updated_at":"2026-07-09T03:55:55.174192+00:00","title_quality_ok":true,"display_title":"Precise Measurement of the e+ e- --> pi+ pi- (gamma) Cross Section with the Initial-State Radiation Method at BABAR","render_title":"Precise Measurement of the e+ e- --> pi+ pi- (gamma) Cross Section with the Initial-State Radiation Method at BABAR"},"hub":{"state":{"work_id":"8034855c-344f-4318-b073-e7b48263c760","tier":"hub","tier_reason":"10+ Pith inbound or 1,000+ external citations","pith_inbound_count":16,"external_cited_by_count":null,"distinct_field_count":3,"first_pith_cited_at":"2020-06-08T18:00:04+00:00","last_pith_cited_at":"2026-07-08T17:14:41+00:00","author_build_status":"not_needed","summary_status":"needed","contexts_status":"needed","graph_status":"needed","ask_index_status":"not_needed","reader_status":"not_needed","recognition_status":"not_needed","updated_at":"2026-08-21T06:19:57.449686+00:00","tier_text":"hub"},"tier":"hub","role_counts":[{"context_role":"background","n":3},{"context_role":"dataset","n":2},{"context_role":"method","n":1}],"polarity_counts":[{"context_polarity":"background","n":3},{"context_polarity":"use_dataset","n":2},{"context_polarity":"use_method","n":1}],"runs":{},"summary":{},"graph":{},"authors":[]}}