Mass Hierarchy Resolution in Reactor Anti-neutrino Experiments:   Parameter Degeneracies and Detector Energy Response
  Determination of the neutrino mass hierarchy using a reactor neutrino experiment at $\sim$60 km is analyzed. Such a measurement is challenging due to the finite detector resolution, the absolute energy scale calibration, as well as the degeneracies caused by current experimental uncertainty of $|\Delta m^2_{32}|$. The standard $\chi^2$ method is compared with a proposed Fourier transformation method. In addition, we show that for such a measurement to succeed, one must understand the non-linearity of the detector energy scale at the level of a few tenths of percent. 
X. Qian and D. A. Dwyer and R. D. McKeown and P. Vogel and W. Wang and   C. Zhang
physics.ins-det hep-ex nucl-ex