The decay of45Ti to45Sc

Abstract

The low intensity fl+/E.C, branches in the decay of 45Ti to excited states of 45Sc have been reinvestigated in order to resolve discrepancies in reported branching ratios. A new branch to the 974 keV level, having an intensity of 9.9_+ 1.2 • 10-5/decay has been found. A previously reported branch to the 1237 keV level was found to be in error. The intensities for decay to the levels at 720, 1408 and 1661 keV levels were determined to be 154+ 12, 90.2_+9.7 and 52.5_+ 5.6, respectively, in units of 10 -5 per decay.

Positron and γ-ray intensities in the decay of 45Ti

“…Porter et al [22] and Zuk et al [23] is (84.80 ± 0.13)% and is based on theoretical values of Zweifel [31]. However, this result had not been experimentally confirmed up to now.…”

“…The intensities of the -rays 1237.07, 1408.6 and 1662.4 keV were found to be smaller as was expected, having values of (0.0161 ± 0.005)%, (0.0696 ± 0.0067)% and (0.00299 ± 0.0039)%, respectively. The comparison of these data with the -ray intensities shown in Table 2, published by the three research groups mentioned above [21][22][23] To evaluate these different data sets, the earlier works have to be examined in detail. All three older studies show at least a few drawbacks in their experimental set-up.…”

“…In 1965 Gföller and Flammersfeld [21] determined the four most intense -rays connected with its decay. Porter et al [22] re-measured the values in 1966, followed by Zuk et al [23] in the early 1970's whose results are considered as standard till today. However, due to limited or unknown sample purity and fragmentary measurement protocols, the reliability of the data of all three studies remains unclear.…”

Synthesis and stability of the [45Ti]Ti–DOTA complex: en route towards aza-macrocyclic 45Ti-based radiopharmaceuticals

“…Titanium radionuclides were first synthesized over 80 years ago 2 and are currently being revived due to their promising characteristics in nuclear medicine, especially for positron emission tomography (PET) imaging. 3–7 From a cyclotron, two types of Ti isotopes can be produced: a long-lived titanium-44 ( 44 Ti: t 1/2 = 60 years) 8 which is not-well suited for direct PET applications, and titanium-45 ( 45 Ti: t 1/2 = 3.08 h, β + : 84.8%, E β+avg = 439 keV) 3 with negligible secondary γ-emission (0.154%) and a low β + maximum endpoint energy of 1040.4 keV, which are favourable features for ensuring good image quality at low dosing for PET imaging.…”

Properties of the low-lying negative parity states in 45Sc

“…The energy levels and their decay properties have been investigated by many authors. When this work was begun the information available on the 45SC nucleus had been obtained from the following experiments : Coulomb excitation [3][4][5][6][7][8][9][10], beta-decay [9], [11,12], radiative proton capture [13][14][15][16], inelastic proton scattering [10], [17][18][19][20][21], one or two particle transfer reactions [22][23][24][25] and the (a, py) reaction [26,27]. The low-lying negative parity states from I' = 1/2to 15/2-have been extensively discussed in all these papers.…”