Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comparison of two experiments on radiative neutron decay   Over 10 years ago we proposed an experiment on measuring the characteristics
of radiative neutron decay in papers [1, 2]. At the same time we had published
the theoretical spectrum of radiative gamma quanta, calculated within the
framework of the electroweak interactions, on the basis of which we proposed
the methodology for the future experiment [3,4]. However, because we were
denied beam time on the intensive cold neutron beam at ILL (Grenoble, France)
for a number of years, we could only conduct the experiment in 2005 on the
newly opened FRMII reactor of Technical University of Muenchen. The main result
of this experiment was the discovery of radiative neutron decay and the
measurement of its relative intensity B.R.= (3.2+-1.6)10-3 with C.L.=99.7% for
radiative gamma quanta with energy over 35 kev [5,6]. Over a year after our
first announcement about the results of the conducted experiment, "Nature" [7]
published a letter asserting that its authors have also measured the branching
ratio of radiative neutron decay B.R.= (3.13+-0.34)10-3 with C.L.=68% and gamma
quanta energy from 15 to 340 kev. This article aims to compare these two
experiments. It is shown that the use of strong magnetic fields in the NIST
(Washington, USA) experiment methodology not only prevents any exact
measurement of the branching ratio and identification of radiative neutron
decay events, but also makes registration of ordinary neutron decay events
impossible.

14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
16
The categories of this paper are: stat
19
The categories of this paper are: eess
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con