We present the first high significance detection ($4.1sigma$) of the Baryon Acoustic Oscillations (BAO) feature in the galaxy bispectrum of the twelfth data release (DR12) of the Baryon Oscillation Spectroscopic Survey (BOSS) CMASS sample ($0.43 leq z leq 0.7$). We measured the scale dilation parameter, $alpha$, using the power spectrum, bispectrum, and both simultaneously for DR12, plus 2048 MultiDark-PATCHY mocks in the North and South Galactic Caps (NGC and SGC, respectively), and the volume weighted averages of those two samples (N+SGC). The fitting to the mocks validated our analysis pipeline, yielding values consistent with the mock cosmology. By fitting to the power spectrum and bispectrum separately, we tested the robustness of our results, finding consistent values from the NGC, SGC and N+SGC in all cases. We found $D_{mathrm{V}} = 2032 pm 24 (mathrm{stat.}) pm 15 (mathrm{sys.})$ Mpc, $D_{mathrm{V}} = 2038 pm 55 (mathrm{stat.}) pm 15 (mathrm{sys.})$ Mpc, and $D_{mathrm{V}} = 2031 pm 22 (mathrm{stat.}) pm 10 (mathrm{sys.})$ Mpc from the N+SGC power spectrum, bispectrum and simultaneous fitting, respectively.
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