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アスタチン (At )には、33種類の同位体 が知られている。全て放射性同位体 で、原子量は191から223の間である。23種類の準安定励起状態 も存在する。最も寿命の長い同位体は210 Atで、半減期は8.3時間である。最も寿命の短い同位体は213 Atで、半減期は125ナノ秒である。
同位体核種
Z(p )
N(n )
同位体質量 (u )
半減期
核スピン数
天然存在比
天然存在比 (範囲)
励起エネルギー
191 At
85
106
1.7(+11-5) ms
(1/2+)
191m At
2.1(+4-3) ms
(7/2-)
192 At
85
107
192.00314(28)
11.5(0.6) ms
3+#
192m At
330(90)# keV
88(6) ms
(9-,10-)
193 At
85
108
192.99984(6)
28(+5-4) ms
(1/2+)
193m1 At
50 keV
21(5) ms
(7/2-)
193m2 At
39 keV
27(+4-5) ms
(13/2+)
194 At
85
109
193.99873(20)
~40 ms
3+#
194m At
480(190) keV
~250 ms
10-#
195 At
85
110
194.996268(10)
328(20) ms
(1/2+)
195m At
34(7) keV
147(5) ms
9/2-#
196 At
85
111
195.99579(6)
253(9) ms
3+#
196m1 At
-30(80) keV
20# ms
10-#
196m2 At
157.9(1) keV
11 µs
5+#
197 At
85
112
196.99319(5)
0.390(16) s
(9/2-)
197m At
52(10) keV
2.0(2) s
(1/2+)
198 At
85
113
197.99284(5)
4.2(3) s
(3+)
198m At
330(90)# keV
1.0(2) s
(10-)
199 At
85
114
198.99053(5)
6.92(13) s
(9/2-)
200 At
85
115
199.990351(26)
43.2(9) s
(3+)
200m1 At
112.7(30) keV
47(1) s
(7+)
200m2 At
344(3) keV
3.5(2) s
(10-)
201 At
85
116
200.988417(9)
85(3) s
(9/2-)
202 At
85
117
201.98863(3)
184(1) s
(2,3)+
202m1 At
190(40) keV
182(2) s
(7+)
202m2 At
580(40) keV
460(50) ms
(10-)
203 At
85
118
202.986942(13)
7.37(13) min
9/2-
204 At
85
119
203.987251(26)
9.2(2) min
7+
204m At
587.30(20) keV
108(10) ms
(10-)
205 At
85
120
204.986074(16)
26.2(5) min
9/2-
205m At
2339.65(23) keV
7.76(14) µs
29/2+
206 At
85
121
205.986667(22)
30.6(13) min
(5)+
206m At
807(3) keV
410(80) ns
(10)-
207 At
85
122
206.985784(23)
1.80(4) h
9/2-
208 At
85
123
207.986590(28)
1.63(3) h
6+
209 At
85
124
208.986173(8)
5.41(5) h
9/2-
210 At
85
125
209.987148(8)
8.1(4) h
(5)+
210m1 At
2549.6(2) keV
482(6) µs
(15)-
210m2 At
4027.7(2) keV
5.66(7) µs
(19)+
211 At
85
126
210.9874963(30)
7.214(7) h
9/2-
212 At
85
127
211.990745(8)
0.314(2) s
(1-)
212m1 At
223(7) keV
0.119(3) s
(9-)
212m2 At
4771.6(11) keV
152(5) µs
(25-)
213 At
85
128
212.992937(5)
125(6) ns
9/2-
214 At
85
129
213.996372(5)
558(10) ns
1-
214m1 At
59(9) keV
265(30) ns
214m2 At
231(6) keV
760(15) ns
9-
215 At
85
130
214.998653(7)
0.10(2) ms
9/2-
216 At
85
131
216.002423(4)
0.30(3) ms
1-
216m At
413(5) keV
100# µs
(9-)
217 At
85
132
217.004719(5)
32.3(4) ms
9/2-
218 At
85
133
218.008694(12)
1.5(3) s
1-#
219 At
85
134
219.011162(4)
56(3) s
5/2-#
220 At
85
135
220.01541(6)
3.71(4) min
3(-#)
221 At
85
136
221.01805(21)#
2.3(2) min
3/2-#
222 At
85
137
222.02233(32)#
54(10) s
223 At
85
138
223.02519(43)#
50(7) s
3/2-#
Isotope masses from Ame2003 Atomic Mass Evaluation by G. Audi, A.H. Wapstra, C. Thibault, J. Blachot and O. Bersillon in Nuclear Physics A729 (2003).
Isotopic compositions and standard atomic masses from Atomic weights of the elements. Review 2000 (IUPAC Technical Report) . Pure Appl. Chem. Vol. 75, No. 6, pp. 683-800, (2003) and Atomic Weights Revised (2005) .
Half-life, spin, and isomer data selected from these sources. Editing notes on this article's talk page.
Audi, Bersillon, Blachot, Wapstra. The Nubase2003 evaluation of nuclear and decay properties , Nuc. Phys. A 729, pp. 3-128 (2003).
National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the NuDat 2.1 database (retrieved Sept. 2005).
David R. Lide (ed.), Norman E. Holden in CRC Handbook of Chemistry and Physics, 85th Edition , online version. CRC Press. Boca Raton, Florida (2005). Section 11, Table of the Isotopes.