Particle and Nuclear Physics Seminar at J-PARC

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DATE: 2015 July. 7th 15:00-16:00

PLACE:Tokai 1st Buiding Room115

New results of 13 measurement via the Hydrogenchannel using full data with the Double Chooz Far detector


SPEAKER: Prof. Ralitsa Sharankova
(Tokyo University of Technology)

CONTACT: Prof. Shunzo Kumano,


Double Chooz is a reactor neutrino experiment aimed
at precise measurement of the neutriro mixing angle 13.
Inverse beta decays from antineutrino interactions are
observed as coincidences of a prompt signal (positron)
and a delayed signal (neutron capture). The main analysis
channel uses neutron captures on Gadolinium. However
a supplementary channel exists that uses captures on
In this talk we report new results of the Double Chooz
13 measurement via the Hydrogen capture channel
using the full Far detector-only dataset. In this analysis
backgrounds are greatly suppressed due to innovative
background rejection techniques. These include a
neural-network- based multivariate analysis and pulse
shape discrimination that takes advantage of the full
channel readout by Flash-ADCs. The neutrino spectrum
distortion that was observed in the Gd analysis is
checked using the independent H capture sample.
Combining the H and Gd samples results in more
than a factor two increase in statistics.This could be
used to enhance the sensitivity of our Near+Far detector
analysis, especially in the early phase.