@article{10902/2005, year = {2009}, month = {11}, url = {http://hdl.handle.net/10902/2005}, abstract = {A combined mass and particle identification fit is used to make the first observation of the decay B̅ s0→Ds±K∓ and measure the branching fraction of B̅ s0→Ds±K∓ relative to B̅ s0→Ds+π-. This analysis uses 1.2  fb-1 integrated luminosity of pp̅ collisions at √s=1.96  TeV collected with the CDF II detector at the Fermilab Tevatron collider. We observe a B̅ s0→Ds±K∓ signal with a statistical significance of 8.1σ and measure B(B̅ s0→Ds±K∓)/B(B̅ s0→Ds+π-)=0.097±0.018(stat)±0.009(syst).}, publisher = {American Physical Society}, publisher = {Physical Review Letters, vol 103, iss. 19, art. num. 191802 (2009)}, title = {First Observation of B̅ s0→Ds±K∓ and Measurement of the Ratio of Branching Fractions B(B̅ s0→Ds±K∓)/B(B̅ s0→Ds+π-)}, author = {Aaltonen, Timo Antero and Akimoto, Takashi and Albrow, Michael G. and Álvarez González, Bárbara and Amerio, Silvia and Amidei, Dante and Anastassov, Anton and Annovi, Alberto and Antos, Jaroslav and Apollinari, Giorgio and Casal Laraña, Bruno and Cuevas Maestro, Francisco Javier and Gómez Gramuglio, Gervasio and Rodrigo Anoro, Teresa and Ruiz Jimeno, Alberto and Scodellaro, Luca and Vila Álvarez, Iván and Vilar Cortabitarte, Rocío and Apresyan, Artur and Adelman, Jahred}, }