Measurements of the branching fractions for B(s) → D(s)πππ and Λb0 → Λc+πππ

Branching fractions of the decays H-b -> H-c pi(-)pi(+)pi(-) relative to H-b -> H-c pi(-) are presented, where H-b (H-c) represents (B) over bar (0) (D+), B-(D-0), (B) over bar (0)(s) (D-s(+)), and Lambda(0)(b) (Lambda(+)(c)). The measurements are performed with the LHCb detector using 35 pb(-1) of data collected at root s = 7 TeV. The ratios of branching fractions are measured to be [B (B) over bar -> D+pi(-)pi(+)pi(-))]/[B((B) over bar (0)-> D+pi(-))] = 2.38 +/- 0.11 +/- 0.21, [B(B- -> D-0 pi(-)pi(+)pi(-))]/[B(B- -> D-0 pi(-))] = 1.27 +/- 0.06 +/- 0.11, [B((B) over bar (0)(s) -> D-s(+)pi(-)pi(+)pi(-))]/[B((B) over bar (0)(s) -> D-s(+)pi(-))] = 2.01 +/- 0.37 +/- 0.20, [B(Lambda(0)(b) ->Lambda(+)(c)pi(-) pi(+)pi(-))]/[B(Lambda(0)(b) ->Lambda(+)(c)pi(-))] = 1.43 +/- 0.16 +/- 0.13 We also report measurements of partial decay rates of these decays to excited charm hadrons. These results are of comparable or higher precision than existing measurements.