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Measurements of b hadron production ratios in proton-proton collisions at a center-of-mass energy of 7 TeV with an integrated luminosity of 3 pb(-1) are presented. We study the ratios of strange B meson to light B meson production f(s)/(f(u) + f(d)) and Lambda(0)(b) baryon to light B meson production f(Lambda b)/(f(u) + f(d)) as a function of the charmed hadron-muon pair transverse momentum p(T) and the b hadron pseudorapidity eta, for p(T) between 0 and 14 GeV and eta between 2 and 5. We find that f(s)/(f(u) + f(d)) is consistent with being independent of p(T) and eta, and we determine f(s)/(f(u) + f(d)) = 0.134 +/- 0.004(-0.010)(+0.011), where the first error is statistical and the second systematic. The corresponding ratio f(Lambda b)/(f(u) + f(d)) is found to be dependent upon the transverse momentum of the charmed hadron-muon pair, f(Lambda b)/(f(u) + f(d)) = (0.404 +/- 0.017(stat)+/- 0.027(syst)+/-0.105(Br)) x [1-(0.031 +/- 0.004(sta)+/-0.003(syst) x p(T)(GeV)], where Br reflects an absolute scale uncertainty due to the poorly known branching fraction B(Lambda(+)(c) -> pK(-)pi(+). We extract the ratio of strange B meson to light neutral B meson production f(s)/f(d) by averaging the result reported here with two previous measurements derived from the relative abundances of (B) over bar (0)(s) -> D-s(+) pi(-) to (B) over bar (0) -> D+K- and (B) over bar (0) -> D+ pi(-). We obtain f(s)/f(d) = 0.267(-0.020)(+0.021).
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Jian Wang, Matthias Finger, Qian Wang, Yiming Li, Matthias Wolf, Varun Sharma, Yi Zhang, Konstantin Androsov, Jan Steggemann, Xin Chen, Rakesh Chawla, Matteo Galli, Anna Mascellani, João Miguel das Neves Duarte, Tagir Aushev, Tian Cheng, Yixing Chen, Werner Lustermann, Andromachi Tsirou, Alexis Kalogeropoulos, Andrea Rizzi, Ioannis Papadopoulos, Paolo Ronchese, Hua Zhang, Siyuan Wang, Tao Huang, David Vannerom, Michele Bianco, Sebastiana Gianì, Sun Hee Kim, Kun Shi, Abhisek Datta, Federica Legger, Gabriele Grosso, Ji Hyun Kim, Donghyun Kim, Zheng Wang, Sanjeev Kumar, Wei Li, Yong Yang, Geng Chen, Ajay Kumar, Ashish Sharma, Georgios Anagnostou, Joao Varela, Csaba Hajdu, Muhammad Ahmad, Ioannis Evangelou, Milos Dordevic, Meng Xiao, Sourav Sen, Xiao Wang, Kai Yi, Jing Li, Rajat Gupta, Zhen Liu, Hui Wang, Seungkyu Ha, Long Wang, Pratyush Das, Anton Petrov, Xin Sun, Xin Gao, Valérie Scheurer, Giovanni Mocellin, Muhammad Ansar Iqbal, Lukas Layer