6 ADs      $0.090^{+0.008}_{-0.009}$   $2.59^{+0.19}_{-0.20}$
      2014/6/24 [@DB_nH]       217 days   6 ADs (nH)        $0.083\pm0.018$                  -
     2015/5/13 [@DB_2015]      621 days    6+8 ADs          $0.084\pm0.005$            $2.42\pm0.11$

  : Daya Bay measurements on $\sin^22\theta_{13}$ and $\Delta m^2_{ee}$. The first uncertainty of $\sin^22\theta_{13}$ in the first two rows is the statistical error and the second is the systematic one. The unit of $\Delta m^2_{ee}$ is $10^{-3}$ eV$^2$. \[tab:sens\]

Daya Bay has accumulated the largest reactor antineutrino sample in the world, which enables many precision measurements. The most precise reactor antineutrino spectrum has been measured [@DB_reactor]. A search for a sterile neutrino has significantly extended the exclusion area in the low-mass region of the $\sin^22\theta_{14}$-$\Delta m^2_{41}$ parameter space [@DB_sterile]. Many exotic searches are ongoing. The Daya Bay experiment plans to operate until 2020. A 3%-precision measurement on both $\sin^22\theta_{13}$ and $\Delta m^2_{ee}$ is expected.

Design and Features {#design}
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In a reactor neutrino experiment, the sensitivity or precision in $\theta_{13}$ depends on how well the rate deficit and distortion in the energy spectrum are determined. When the exposure, defined as the product of the target mass of the far site detector in tons, the thermal power of the reactor in GW, and the live time in years, is larger 