Title Precision measurement of the X(3872) mass in $J/\psi\pi^{+}\pi^{-}$ decays Author Aaltonen, T. Van Remortel, N. et al. Faculty/Department Faculty of Sciences. Physics Publication type article Publication 2009 New York, N.Y. , 2009 Subject Physics Source (journal) Physical review letters. - New York, N.Y. Volume/pages 103(2009) :15 , p. 152001,1-152001,8 ISSN 0031-9007 ISI 000270672100011 Carrier E Target language English (eng) Full text (Publishers DOI) Affiliation University of Antwerp Abstract We present an analysis of the mass of the X(3872) reconstructed via its decay to J/ψπ+π- using 2.4  fb-1 of integrated luminosity from pp̅ collisions at √s=1.96  TeV, collected with the CDF II detector at the Fermilab Tevatron. The possible existence of two nearby mass states is investigated. Within the limits of our experimental resolution the data are consistent with a single state, and having no evidence for two states we set upper limits on the mass difference between two hypothetical states for different assumed ratios of contributions to the observed peak. For equal contributions, the 95% confidence level upper limit on the mass difference is 3.6  MeV/c2. Under the single-state model the X(3872) mass is measured to be 3871.61±0.16(stat)±0.19(syst)  MeV/c2, which is the most precise determination to date. Full text (open access) https://repository.uantwerpen.be/docman/irua/78bdfb/fd450149.pdf E-info http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000270672100011&DestLinkType=RelatedRecords&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000270672100011&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000270672100011&DestLinkType=CitingArticles&DestApp=ALL_WOS&UsrCustomerID=ef845e08c439e550330acc77c7d2d848 Handle