In this work, using a scintillation detector with Strontium-90 source as a try to
measure the electronic neutrino mass from a simple technique and different from what is
used in this area where current techniques used are very complex and require s
ubstantial
amounts.
Also, detector calibration (to find the straight calibration equation), in addition to
identified the maximum energy of β- particles (electrons), experimentally, by selection the
channel number and then finding the energy value from the calibration equation (as a
straight line).
We have studied the disintegration changed energy with absorbent material which is
an aluminum slices that have different thickness.
We have observed the decrease in the values of the maximum energy of the electrons
with increases the thickness of the slices. The energy changes with thickness as: E = f (x),
(a straight line have a negative inclination).
Applying Fermi 's theory and Kurie's plot allowed to find the maximum energy of
disintegration electrons (1697,58 keV), this value is so close to experimental value
(1653,45 keV), with dubity (2,6%)
We have found that the electronic mass neutrino mass is almost to be non-existent, or
we can said that the Strontium-90 disintegration does not allow to measure mass neutrino
mass accurately, this is due to the high value of the disintegration energy of the Strontium-
90 isotope.
In this experimental work, the instruments used (detector, calibrating sources) has been calibrating, the calibration line of the detector deduced and it has been finding that the equation of calibration line takes the form:
The resolution power R
has been studying as function of the distance between the activity source and detector; the results obtained show that R decrease by increase the energy of the lines spectrum, this mean that the detector resolution power become bigger.
It has been measured the LC، LD and MDA using two different methods of background radiation value, trapezium method and classical method, for two different distances between radioactivity source and detector: (9,3cm) and (10cm). The results show:
1- There is similar comportment of the LC، LD and MDA in function energy and the distance between radioactivity source and detector.
2- The trapezium method gives better results from the classical method to the radiation background, and this leads to lesser MDA value, this means that the sensibility is bigger to measure this quantity.
3- The relative error using MDA is (5%) for large values, and (10%) for small values
Gamma rays
sodium iodide activated by Thallium
calibration line
resolution detector
source activity
detector efficiency
minimum detectable activity
background radiation level
أشعة غاما
كاشف يوديد الصوديوم المشوب بالتاليوم
مستقيم المعايرة
قدرة الفصل الطيفية
منبع مُشع
كفاءة كاشف
الحد الأدنى لمكشف
ضجيج خلفي
المزيد..