Publikace
> 'Measurement of the 2νββ decay of
100Mo to the excited 0
1+ state in the NEMO3 experiment'
Measurement of the 2νββ decay of 100Mo to the excited 01+ state in the NEMO3 experiment
Autor
Rok
2003
Časopis
Ph.D. Thesis, Université Paris-sud & CTU Prague
Web
Obsah
The NEMO3 detector was designed for the study of double beta decay
and in particular to search for the neutrinoless double beta decay process (0νββ).
The intended sensitivity in terms of a half-life limit for
the 0νββ decay
is of the order of 1025 yr
which corresponds to an effective neutrino mass
〈mν〉
on the level of (0.3 – 0.1) eV.
The 0νββ process is today the most promising test of
the Majorana nature of the neutrino.
The detector was constructed in the Modane Underground Laboratory
(LSM) in France
by an international collaboration
including France, Russia, the Czech Republic,
the USA, the UK, Finland, and Japan.
The experiment has been taking data since May 2002.
The quantity of 100Mo in the detector (7 kg)
allows an efficient measurement of
the two-neutrino double beta decay (2νββ) of 100Mo
to the excited 01+ state
(eeNγ channel).
Monte-Carlo simulations of the effect
and of all the relative sources of background
have been produced
in order to define a set of appropriate selection criteria.
Both Monte-Carlo simulations
and special runs with sources of 208Tl and 214Bi showed
that the only significant background in the eeNγ channel
comes from radon
that penetrated inside the wire chamber of NEMO3.
The experimental data acquired from May 2002 to May 2003 have been analysed
in order to determine the signal from
the 2νββ decay of 100Mo
to the excited 01+ state
and the corresponding background level.
The physical result,
which was obtained at the level of four standard deviations,
is given in the form of an interval of half-life values
at 95% confidence level.
The Ph.D. theses has been supported with a scholarship of the French government (thèse en cotutelle)
and has been realized at both LAL Orsay/IN2P3/CNRS and the FNSPE CTU Prague.
Projekty
Příklad citace článku:
L. Vála, "Measurement of the 2νββ decay of 100Mo to the excited 01+ state in the NEMO3 experiment", Ph.D. Thesis, Université Paris-sud & CTU Prague (2003)