Isotopes of lanthanum
List of isotopes
Bold for isotopes with half-lives longer than the age of the universe (nearly stable) Abbreviations: EC: Electron capture IT: Isomeric transition Bold for stable isotopes, bold italics for near-stable isotopes (half-life longer than the age of the universe) Primordial radionuclide Fission product

Isotopes of lanthanum

Section Title: List of isotopes
Table Section Text: Bold for isotopes with half-lives longer than the age of the universe (nearly stable) Abbreviations: EC: Electron capture IT: Isomeric transition Bold for stable isotopes, bold italics for near-stable isotopes (half-life longer than the age of the universe) Primordial radionuclide Fission product

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life	decay mode(s)	daughter isotope(s)	nuclear spin and parity	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)

excitation energy

117La	57	60	116.95007(43)#	23.5(26) ms	β+	117Ba	(3/2+,3/2−)

p	116Ba

117mLa	151(12) keV	10(5) ms	(9/2+)

118La	57	61	117.94673(32)#	200# ms	β+	118Ba

119La	57	62	118.94099(43)#	1# s	β+	119Ba	11/2−#

120La	57	63	119.93807(54)#	2.8(2) s	β+	120Ba

β+, p	119Cs

121La	57	64	120.93301(54)#	5.3(2) s	β+	121Ba	11/2−#

β+, p	120Cs

122La	57	65	121.93071(32)#	8.6(5) s	β+	122Ba

β+, p	121Cs

123La	57	66	122.92624(21)#	17(3) s	β+	123Ba	11/2−#

124La	57	67	123.92457(6)	29.21(17) s	β+	124Ba	(7−,8−)

124mLa	100(100)# keV	21(4) s	low(+#)

125La	57	68	124.920816(28)	64.8(12) s	β+	125Ba	(11/2−)

125mLa	107.0(10) keV	390(40) ms	(3/2+)

126La	57	69	125.91951(10)	54(2) s	β+	126Ba	(5)(+#)

126mLa	210(410) keV	20(20) s	(0−,1−,2−)

127La	57	70	126.916375(28)	5.1(1) min	β+	127Ba	(11/2−)

127mLa	14.8(12) keV	3.7(4) min	β+	127Ba	(3/2+)

IT	127La

128La	57	71	127.91559(6)	5.18(14) min	β+	128Ba	(5+)

128mLa	100(100)# keV	<1.4 min	IT	128La	(1+,2−)

129La	57	72	128.912693(22)	11.6(2) min	β+	129Ba	3/2+

129mLa	172.1(4) keV	560(50) ms	IT	129La	11/2−

130La	57	73	129.912369(28)	8.7(1) min	β+	130Ba	3(+)

131La	57	74	130.91007(3)	59(2) min	β+	131Ba	3/2+

131mLa	304.52(24) keV	170(10) µs	11/2−

132La	57	75	131.91010(4)	4.8(2) h	β+	132Ba	2−

132mLa	188.18(11) keV	24.3(5) min	IT (76%)	132La	6−

β+ (24%)	132Ba

133La	57	76	132.90822(3)	3.912(8) h	β+	133Ba	5/2+

134La	57	77	133.908514(21)	6.45(16) min	β+	134Ba	1+

135La	57	78	134.906977(11)	19.5(2) h	β+	135Ba	5/2+

136La	57	79	135.90764(6)	9.87(3) min	β+	136Ba	1+

136mLa	255(9) keV	114(3) ms	IT	136La	(8)(−#)

137La	57	80	136.906494(14)	6(2)×104 y	EC	137Ba	7/2+

138La	57	81	137.907112(4)	1.02(1)×1011 y	β+ (66.4%)	138Ba	5+	9.0(1)×10−4

β− (33.6%)	138Ce

138mLa	72.57(3) keV	116(5) ns	(3)+

139La	57	82	138.9063533(26)	Stable	7/2+	0.99910(1)

140La	57	83	139.9094776(26)	1.6781(3) d	β−	140Ce	3−

141La	57	84	140.910962(5)	3.92(3) h	β−	141Ce	(7/2+)

142La	57	85	141.914079(6)	91.1(5) min	β−	142Ce	2−

143La	57	86	142.916063(17)	14.2(1) min	β−	143Ce	(7/2)+

144La	57	87	143.91960(5)	40.8(4) s	β−	144Ce	(3−)

145La	57	88	144.92165(10)	24.8(20) s	β−	145Ce	(5/2+)

146La	57	89	145.92579(8)	6.27(10) s	β− (99.99%)	146Ce	2−

β−, n (.007%)	145Ce

146mLa	130(130) keV	10.0(1) s	β−	146Ce	(6−)

147La	57	90	146.92824(5)	4.015(8) s	β− (99.96%)	147Ce	(5/2+)

β−, n (.04%)	146Ce

148La	57	91	147.93223(6)	1.26(8) s	β− (99.85%)	148Ce	(2−)

β−, n (.15%)	147Ce

149La	57	92	148.93473(34)#	1.05(3) s	β− (98.6%)	149Ce	5/2+#

β−, n (1.4%)	148Ce

150La	57	93	149.93877(43)#	510(30) ms	β− (97.3%)	150Ce	(3+)

β−, n (2.7%)	149Ce

151La	57	94	150.94172(43)#	300# ms [>300 ns]	β−	151Ce	5/2+#

152La	57	95	151.94625(43)#	200# ms [>300 ns]	β−	152Ce

153La	57	96	152.94962(64)#	150# ms [>300 ns]	β−	153Ce	5/2+#

154La	57	97	153.95450(64)#	100# ms	β−	154Ce

155La	57	98	154.95835(86)#	60# ms	β−	155Ce	5/2+#

Sentence(s)

¹⁴⁰La has a half-life of 1.6781 days.

final_sentence: ¹⁴⁰La has a half-life of 1.6781 days.