Isotopes of xenon
List of isotopes
Abbreviations: EC: Electron capture IT: Isomeric transition Bold for stable isotopes Suspected of undergoing β⁺β⁺ decay to ¹²⁶Te Theoretically capable of spontaneous fission Used in a method of radiodating groundwater and to infer certain events in the Solar System's history Fission product Has medical uses Suspected of undergoing β−β− decay to ¹³⁴Ba with a half-life over 11×10¹⁵ years Most powerful known neutron absorber, produced in nuclear power plants as a decay product of ¹³⁵I, itself a decay product of ¹³⁵Te, a fission product.

Isotopes of xenon

Section Title: List of isotopes
Table Section Text: Abbreviations: EC: Electron capture IT: Isomeric transition Bold for stable isotopes Suspected of undergoing β⁺β⁺ decay to ¹²⁶Te Theoretically capable of spontaneous fission Used in a method of radiodating groundwater and to infer certain events in the Solar System's history Fission product Has medical uses Suspected of undergoing β−β− decay to ¹³⁴Ba with a half-life over 11×10¹⁵ years Most powerful known neutron absorber, produced in nuclear power plants as a decay product of ¹³⁵I, itself a decay product of ¹³⁵Te, a 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

108Xe	54	54	58(+106-23) µs	α	104Te	0+

109Xe	54	55	13(2) ms	α	105Te

110Xe	54	56	109.94428(14)	310(190) ms [105(+35−25) ms]	β+	110I	0+

α	106Te

111Xe	54	57	110.94160(33)#	740(200) ms	β+ (90%)	111I	5/2+#

α (10%)	107Te

112Xe	54	58	111.93562(11)	2.7(8) s	β+ (99.1%)	112I	0+

α (.9%)	108Te

113Xe	54	59	112.93334(9)	2.74(8) s	β+ (92.98%)	113I	(5/2+)#

β+, p (7%)	112Te

α (.011%)	109Te

β+, α (.007%)	109Sb

114Xe	54	60	113.927980(12)	10.0(4) s	β+	114I	0+

115Xe	54	61	114.926294(13)	18(4) s	β+ (99.65%)	115I	(5/2+)

β+, p (.34%)	114Te

β+, α (3×10−4%)	111Sb

116Xe	54	62	115.921581(14)	59(2) s	β+	116I	0+

117Xe	54	63	116.920359(11)	61(2) s	β+ (99.99%)	117I	5/2(+)

β+, p (.0029%)	116Te

118Xe	54	64	117.916179(11)	3.8(9) min	β+	118I	0+

119Xe	54	65	118.915411(11)	5.8(3) min	β+	119I	5/2(+)

120Xe	54	66	119.911784(13)	40(1) min	β+	120I	0+

121Xe	54	67	120.911462(12)	40.1(20) min	β+	121I	(5/2+)

122Xe	54	68	121.908368(12)	20.1(1) h	β+	122I	0+

123Xe	54	69	122.908482(10)	2.08(2) h	EC	123I	1/2+

123mXe	185.18(22) keV	5.49(26) µs	7/2(−)

124Xe	54	70	123.905893(2)	1.8(0.5 (stat), 0.1 (sys))×1022 y	Double EC	124Te	0+	9.52(3)×10−4

125Xe	54	71	124.9063955(20)	16.9(2) h	β+	125I	1/2(+)

125m1Xe	252.60(14) keV	56.9(9) s	IT	125Xe	9/2(−)

125m2Xe	295.86(15) keV	0.14(3) µs	7/2(+)

126Xe	54	72	125.904274(7)	Observationally Stable	0+	8.90(2)×10−4

127Xe	54	73	126.905184(4)	36.345(3) d	EC	127I	1/2+

127mXe	297.10(8) keV	69.2(9) s	IT	127Xe	9/2−

128Xe	54	74	127.9035313(15)	Stable	0+	0.019102(8)

129Xe	54	75	128.9047794(8)	Stable	1/2+	0.264006(82)

129mXe	236.14(3) keV	8.88(2) d	IT	129Xe	11/2−

130Xe	54	76	129.9035080(8)	Stable	0+	0.040710(13)

131Xe	54	77	130.9050824(10)	Stable	3/2+	0.212324(30)

131mXe	163.930(8) keV	11.934(21) d	IT	131Xe	11/2−

132Xe	54	78	131.9041535(10)	Stable	0+	0.269086(33)

132mXe	2752.27(17) keV	8.39(11) ms	IT	132Xe	(10+)

133Xe	54	79	132.9059107(26)	5.2475(5) d	β−	133Cs	3/2+

133mXe	233.221(18) keV	2.19(1) d	IT	133Xe	11/2−

134Xe	54	80	133.9053945(9)	Observationally Stable	0+	0.104357(21)

134m1Xe	1965.5(5) keV	290(17) ms	IT	134Xe	7−

134m2Xe	3025.2(15) keV	5(1) µs	(10+)

135Xe	54	81	134.907227(5)	9.14(2) h	β−	135Cs	3/2+

135mXe	526.551(13) keV	15.29(5) min	IT (99.99%)	135Xe	11/2−

β− (.004%)	135Cs

136Xe	54	82	135.907219(8)	2.165(0.016 (stat), 0.059 (sys))×1021 y	β−β−	136Ba	0+	0.088573(44)

136mXe	1891.703(14) keV	2.95(9) µs	6+

137Xe	54	83	136.911562(8)	3.818(13) min	β−	137Cs	7/2−

138Xe	54	84	137.91395(5)	14.08(8) min	β−	138Cs	0+

139Xe	54	85	138.918793(22)	39.68(14) s	β−	139Cs	3/2−

140Xe	54	86	139.92164(7)	13.60(10) s	β−	140Cs	0+

141Xe	54	87	140.92665(10)	1.73(1) s	β− (99.45%)	141Cs	5/2(−#)

β−, n (.043%)	140Cs

142Xe	54	88	141.92971(11)	1.22(2) s	β− (99.59%)	142Cs	0+

β−, n (.41%)	141Cs

143Xe	54	89	142.93511(21)#	0.511(6) s	β−	143Cs	5/2−

144Xe	54	90	143.93851(32)#	0.388(7) s	β−	144Cs	0+

β−, n	143Cs

145Xe	54	91	144.94407(32)#	188(4) ms	β−	145Cs	(3/2−)#

146Xe	54	92	145.94775(43)#	146(6) ms	β−	146Cs	0+

147Xe	54	93	146.95356(43)#	130(80) ms [0.10(+10−5) s]	β−	147Cs	3/2−#

β−, n	146Cs

Sentence(s)

Of known isomers, the longest-lived is ¹³¹ᵐXe with a half-life of 11.934 days.

final_sentence: Of known isomers, the longest-lived is ¹³¹ᵐXe with a half-life of 11.934 days.