By: raman on Mercoledì 27 Gennaio 2016 16:08
@Nevanlinna
Il suo dilemma è facilmente risolvibile. Basta mettere accanto ai rivelatori home-made dei rivelatori professionali, come per esempio è stato fatto nel lavoro citato in precedenza.
#i#The concomitant absence of counts for the HDS Mirion detector can be explained by the fact that it converts, as the majority of the active detectors, the neutron energy in an electrical signal: for this reason, because of the dead time due to the electrical conversion of the pulses, it may have failed the detection [30].
Moreover, a further explanation is provided by the dramatic decrease of the detector efficiency with the square of the distance from the source. The law 1/R2 can justify the difference between the neutron measurements in the fourth quadrant obtained by means of the BTI Microspec detector and those by the CR39’s. Note that, while the distance of the CR39’s from the AISI 304 steel bar was 3 cm (Teflon calorimeter radius), the distance of both the
active detectors was 30 cm, as can be easily seen in figs. 2 and 3. This defaillance of the active neutron detectors, compared to the passive ones, is expected to be emphasized, in the case that the neutron emissions are not constant over time, and occur by means of neutron quick bursts.#/i#
E' vero che il Mirion non ha visto nulla, ma sa, quello è costruito per trasformare i neutroni in impulsi elettrici e Lei lo sa come sono indigesti i tempi morti. Per cui è meglio affidarsi ai rivelatori integrali. Il mio problema è come si fa a sapere che i neutroni sono emessi a burst, in tal caso. Lei ha qualche idea?