List of levels for 98Y

Authors: Jun Chen, Balraj Singh | Citation: Nucl. Data Sheets 164, 1 (2020) | Cutoff date: 15-Feb-2020

E(level) (keV)	J^π(level)	T_1/2(level)	E(γ) (keV)	Multipolarity	Mixing Ratio	Conversion Coefficient	Additional Data
119.353	1-	0.14 ns 5	119.353 3	M1		0.1115	B(M1)(W.u.)=0.083 +47-22, α=0.1115, α(K)=0.0980 14, α(L)=0.01126 16, α(M)=0.00193 3, α(N)=0.000258 4, α(O)=1.763×10^-5 25
170.78	2-	0.63 µs 2 % IT = 100	51.5 1	M1+E2	0.26 +7-8	1.9	B(E2)(W.u.)=0.61 +44-34, B(M1)(W.u.)=2.49E-5 +35-32, α=1.9 4, α(K)=1.5 3, α(L)=0.28 9, α(M)=0.048 15, α(N)=0.0059 18, α(O)=0.00025 4
170.78	2-	0.63 µs 2 % IT = 100	170.8 1	E2		0.1507	B(E2)(W.u.)=0.140 9, α=0.1507, α(K)=0.1296 19, α(L)=0.0177 3, α(M)=0.00302 5, α(N)=0.000388 6, α(O)=2.05E-5 3
358.13	(1,2-)		187.1 2	[D,E2]		0.06	α=0.06 4
374.97	4-	35.2 ns 5	204.3 1	E2		0.0789	B(E2)(W.u.)=1.560 +28-27, α=0.0789, α(K)=0.0683 10, α(L)=0.00890 13, α(M)=0.001522 22, α(N)=0.000197 3, α(O)=1.100E-5 16
446.07	(3)+	< 0.7 ns	71.3 2	(E1)		0.289	α=0.289 5, α(K)=0.255 5, α(L)=0.0289 5, α(M)=0.00490 8, α(N)=0.000639 11, α(O)=3.89×10^-5 7
446.07	(3)+	< 0.7 ns	275.2 1	[E1]		0.0058	α=0.0058
496.10	(4)-	6.90 µs 5 % IT = 100	49.9 2	E1		0.811	B(E1)(W.u.)=1.21E-8 +23-21, α=0.811 15, α(K)=0.712 13, α(L)=0.0830 16, α(M)=0.0140 3, α(N)=0.00181 4, α(O)=0.0001042 19
	(4)-	6.90 µs 5 % IT = 100	121.2 1	M1+E2	-0.8 2	0.27	B(E2)(W.u.)=0.033 11, B(M1)(W.u.)=7.9E-7 +19-16, α=0.27 6, α(K)=0.23 5, α(L)=0.033 8, α(M)=0.0057 13, α(N)=0.00073 16, α(O)=3.7E-5 7
	(4)-	6.90 µs 5 % IT = 100	325.2 2	[E2]		0.01555	B(E2)(W.u.)=1.7E-5 7, α=0.01555, α(K)=0.01360 20, α(L)=0.001637 24, α(M)=0.000280 4, α(N)=3.68E-5 6, α(O)=2.27E-6 4
547.86	1+		189.7 1	[D,E2]		0.06	α=0.06 4
563.999	(1-,2-)	2.4 ns 12	444.628 20	M1(+E2)	0.9 LT
596.73	(5)-	175 ps 25	100.6 1	M1(+E2)	0.15 LT	0.188	B(M1)(W.u.)=0.102 +20-13, α=0.188 10, α(K)=0.165 9, α(L)=0.0195 15, α(M)=0.00334 25, α(N)=0.00044 3, α(O)=2.93×10^-5 12
600.30	1+	7.5 ns 7	36.2 1	E1		2.02	B(E1)(W.u.)=1.64E-4 +45-39, α=2.02 4, α(K)=1.76 3, α(L)=0.213 4, α(M)=0.0359 6, α(N)=0.00457 8, α(O)=0.000247 4
	1+	7.5 ns 7	52.4 1	M1+E2	0.43 10	2.7	B(E2)(W.u.)=8×10¹ +7-4, B(M1)(W.u.)=0.0011 +6-4, α=2.7 7, α(K)=2.1 5, α(L)=0.47 15, α(M)=0.081 25, α(N)=0.010 3, α(O)=0.00032 6
	1+	7.5 ns 7	429.6 1	[E1]		0.0018	B(E1)(W.u.)=1.8E-8 +10-6, α=0.0018
	1+	7.5 ns 7	481.1 1	E1			B(E1)(W.u.)=5.0E-8 +21-14
	1+	7.5 ns 7	600.2 1	[E1]			B(E1)(W.u.)=7.2E-9 +37-24
658.27	(6-,7-)		54.7 1	M1+E2	0.25 +5-6	1.50	α=1.50 21, α(K)=1.24 15, α(L)=0.21 5, α(M)=0.037 8, α(N)=0.0046 10, α(O)=0.000206 20
666.28	(1+)		66.0 1	D		0.5	α=0.5 1
666.28	(1+)		102.3 1	[E1]		0.1006	α=0.1006, α(K)=0.0887 13, α(L)=0.00992 15, α(M)=0.001682 24, α(N)=0.000222 4, α(O)=1.402×10^-5 20
713.03	(0-,1,2-)		165.3 1	[D,E2]		0.10	α=0.10 8
726.48	(6-)	51 ps 10	129.7 1	[M1]		0.0889	B(M1)(W.u.)=0.170 +43-29, α=0.0889, α(K)=0.0782 11, α(L)=0.00896 13, α(M)=0.001535 22, α(N)=0.000206 3, α(O)=1.406×10^-5 20
726.48	(6-)	51 ps 10	230.4 1	[E2]		0.0514	B(E2)(W.u.)=39 +13-9, α=0.0514, α(K)=0.0446 7, α(L)=0.00567 8, α(M)=0.000970 14, α(N)=0.0001260 18, α(O)=7.27E-6 11
884.49	(7-)	45 ps 15	158.0 1	[M1]		0.0523	B(M1)(W.u.)=0.095 +49-25, α=0.0523, α(K)=0.0460 7, α(L)=0.00525 8, α(M)=0.000898 13, α(N)=0.0001204 17, α(O)=8.26×10^-6 12
884.49	(7-)	45 ps 15	287.8 1	[E2]		0.0236	B(E2)(W.u.)=45 +25-13, α=0.0236, α(K)=0.0206 3, α(L)=0.00252 4, α(M)=0.000431 6, α(N)=5.64E-5 8, α(O)=3.41E-6 5
E(level) (keV)	J^π(level)	T_1/2(level)	E(γ) (keV)	Multipolarity	Mixing Ratio	Conversion Coefficient	Additional Data
986.39	1+		162.2 1	[D,E2]		0.11	α=0.11 8
1070.70	(8-)	< 15 ps	186.2 1	[M1+E2]		0.07	α=0.07 4, α(K)=0.06 4, α(L)=0.008 5, α(M)=0.0014 8, α(N)=0.00018 10, α(O)=1.0×10^-5 5
1070.70	(8-)	< 15 ps	344.2 1	[E2]		0.01286	α=0.01286, α(K)=0.01125 16, α(L)=0.001345 19, α(M)=0.000230 4, α(N)=3.03×10^-5 5, α(O)=1.89E-6 3
1181.50	(10-)	0.78 µs 3 % IT = 100	110.8 1	E2		0.732	B(E2)(W.u.)=0.935 +48-44, α=0.732, α(K)=0.614 9, α(L)=0.0985 15, α(M)=0.01692 25, α(N)=0.00211 3, α(O)=9.25E-5 14

No new experimental references for ⁹⁸Y found in the NSR databases, as of Feb 11, 2021

Mass measurement: 2007Ha32

2006Ca38: measured resonance fluorescence spectra. Collinear laser spectroscopy.

Theory references: consult the NSR database (www.nndc.bnl.gov/nsr/) for four primary references, one dealing with nuclear structure calculations and 3 with decay modes and half-lives.

Q-value: S(2n)=10102 10, S(2p)=25518 9, Q(β^-n)=2577 8 (2017Wa10)

Q(β-)=8992 keV 12	S(n)= 4245 keV 10	S(p)= 11002 keV 9	Q(α)= -6157 keV 8
Reference: 2017WA10

References:
A	⁹⁸Sr β^- decay (0.653 S)	B	⁹⁹Sr β^-n decay (0.269 S)
C	²⁴⁸Cm,²⁵²Cf SF decay	D	²³⁵U(n,Fγ),²⁴¹Pu(n,Fγ)
E	²³⁵U(n,Fγ):DELAYED γ	F	²³⁸U(p,Fγ)

E(level) (keV)	XREF	J^π(level)	T_1/2(level)	E(γ) (keV)	I(γ)	M(γ)	Final Levels
0.0	A B C D E F	0-	0.548 s 2 % β^- = 100 % β^-n = 0.33 3
119.353 3	A C D E F	1-	0.14 ns 5	119.353 3	100	M1	0.0	0-
170.78 5	A C D E F	2-	0.63 µs 2 % IT = 100	51.5 1 170.8 1	17.1 9 100 3	M1+E2 E2	119.353 0.0	1- 0-
358.13 6	A	(1,2-)		187.1 2 238.8 1 357.9 2	100 25 75 15 12.5 25	[D,E2]	170.78 119.353 0.0	2- 1- 0-
374.97 9	A C D E F	4-	35.2 ns 5	204.3 1	100	E2	170.78	2-
446.07 10	C D E F	(3)+	< 0.7 ns	71.3 2 275.2 1	4.9 20 100 6	(E1) [E1]	374.97 170.78	4- 2-
465.7 7		(7+,6+)	2.32 s 8 % β^- = 90 10 % β^-n = 3.44 95 % IT < 20
496.10 11	A C D E F	(4)-	6.90 µs 5 % IT = 100	49.9 2 121.2 1 325.2 2	4.5 6 100 3 2.8 10	E1 M1+E2 [E2]	446.07 374.97 170.78	(3)+ 4- 2-
547.86 5	A C	1+		189.7 1 428.6 1 547.9 1	1.01 14 100 4 7.9 3	[D,E2] E1 [E1]	358.13 119.353 0.0	(1,2-) 1- 0-
563.999 19	A C	(1-,2-)	2.4 ns 12	393.3 1 444.628 20 564.0 1	3.0 8 100 4 22.2 10	M1(+E2) M1,E2	170.78 119.353 0.0	2- 1- 0-
564.0+X	A C	(3-,4-)	180 ns 7	X			563.999	(1-,2-)
595.78 8	A	(1,2-)		237.7 2 476.7 1	53 27 100 5		358.13 119.353	(1,2-) 1-
596.73 14	C D E F	(5)-	175 ps 25	100.6 1	100	M1(+E2)	496.10	(4)-
600.30 4	A C	1+	7.5 ns 7	36.2 1 52.4 1 429.6 1 481.1 1 600.2 1	100 21 36 4 18 3 71 7 20 3	E1 M1+E2 [E1] E1 [E1]	563.999 547.86 170.78 119.353 0.0	(1-,2-) 1+ 2- 1- 0-
E(level) (keV)	XREF	J^π(level)	T_1/2(level)	E(γ) (keV)	I(γ)	M(γ)	Final Levels
601.92 8	A	(0,1,2)		243.7 2 482.7 2	100 50 100 50		358.13 119.353	(1,2-) 1-
603.57 14	C E	(5-,6-)		228.6 1	100		374.97	4-
615.17 12	A C	(2-,3+)		240.2 1	100		374.97	4-
658.27 17	C E	(6-,7-)		54.7 1	100	M1+E2	603.57	(5-,6-)
665.10+X 10	C			101.1 1	100		564.0+X	(3-,4-)
666.28 7	A C	(1+)		51.1 2 66.0 1 102.3 1	37 19 100 8 10.0 19	D [E1]	615.17 600.30 563.999	(2-,3+) 1+ (1-,2-)
713.03 10	A	(0-,1,2-)		165.3 1	100	[D,E2]	547.86	1+
726.48 14	C D E F	(6-)	51 ps 10	129.7 1 230.4 1	100.0 18 7.2 4	[M1] [E2]	596.73 496.10	(5)- (4)-
798.80+X 15	C			133.7 1	100		665.10+X
824.40 6	A	(0-,1,2-)		158.5 3 ? 222.5 1 224.1 1 228.9 1 260.3 1	6.4 36 29 7 26 4 36 7 100 7		666.28 601.92 600.30 595.78 563.999	(1+) (0,1,2) 1+ (1,2-) (1-,2-)
869.47 24	C			265.9 2	100		603.57	(5-,6-)
884.49 15	C D E F	(7-)	45 ps 15	158.0 1 287.8 1	100.0 7 24.6 10	[M1] [E2]	726.48 596.73	(6-) (5)-
908.41 15	A	(0-,1,2-)		306.3 2 308.3 2 343.8 2 ?	31 16 100 19 36 14		601.92 600.30 563.999	(0,1,2) 1+ (1-,2-)
964.30+X 18	C			165.5 1 299?	100 10		798.80+X 665.10+X
972.17 20	C E	(8+)	0.45 µs 15 % IT = 100	313.9 1	100		658.27	(6-,7-)
986.39 6	A	1+		162.2 1 320.1 1 384.5 1 386.0 1 422.3 1 986.1 2	33 5 49 5 13 5 100 5 17.9 13 17.9 21	[D,E2]	824.40 666.28 601.92 600.30 563.999 0.0	(0-,1,2-) (1+) (0,1,2) 1+ (1-,2-) 0-
E(level) (keV)	XREF	J^π(level)	T_1/2(level)	E(γ) (keV)	I(γ)	M(γ)	Final Levels
1053.07 24	C	(6-,7-)		449.5 2	100		603.57	(5-,6-)
1070.70 15	C D E F	(8-)	< 15 ps	186.2 1 344.2 1	100.0 13 28.8 5	[M1+E2] [E2]	884.49 726.48	(7-) (6-)
1163.30+X 20	C			199.0 1 364?	100 16		964.30+X 798.80+X
1181.50 18	C D E F	(10-)	0.78 µs 3 % IT = 100	110.8 1	100	E2	1070.70	(8-)
1199.70 9	A	(1+)		599.2 2 651.9 1 1080.3 2	15 4 51 4 100 8		600.30 547.86 119.353	1+ 1+ 1-
1291.76 16	C F	(9-)		221.0 1 407.3 1	100 9 62 6		1070.70 884.49	(8-) (7-)
1348.50 11	A	(0-,1,2-)		635.6 1 800.3 2 990.2 2	100 11 70 14 34 7		713.03 547.86 358.13	(0-,1,2-) 1+ (1,2-)
1386.8+X 3	C			223.5 2 422.6 2 ?	100 14 23 9		1163.30+X 964.30+X
1464.45 15	A	(0-,1,2-)		798.3 2 864.0 2	96 16 100 20		666.28 600.30	(1+) 1+
1532.68 17	C F	(10-)		240.9 1 462.0 1	100 9 53 6		1291.76 1070.70	(9-) (8-)
1631.5+X 4	C			244.7 2	100		1386.8+X
1679.2 4	C			707.0 3	100		972.17	(8+)
1680.07 15	A	(0-,1,2-)		1132.4 2 1560.5 2	62 18 100 15		547.86 119.353	1+ 1-
1842.93 21	C F	(11-)		310.3 2 551.1 2	89 17 100 17		1532.68 1291.76	(10-) (9-)
1896.8+X 4	C			265.3 2	100		1631.5+X
1898.57 17	A	(0-,1,2-)		1298.5 2 1334.0 3	67 22 100 19		600.30 563.999	1+ (1-,2-)
E(level) (keV)	XREF	J^π(level)	T_1/2(level)	E(γ) (keV)	I(γ)	M(γ)	Final Levels
1945.1 4	C			763.6 3	100		1181.50	(10-)
2100.65 23	C F	(12-)		257.7 2 568.0 2	67 13 100 20		1842.93 1532.68	(11-) (10-)
2178.0+X 5	C			281.2 3	100		1896.8+X
2366.0 3	C			1184.5 2	100		1181.50	(10-)
3165.0 4	C			799.0 3	100		2366.0

E(level) (keV)	J^π(level)	T_1/2(level)	E(γ)	I(γ)	M(γ)	Final Levels
Band 1 - πg_9/2~#νh_11/2, Kπ=4-, prolate.
496.10 11	(4)-	6.90 µs 5 % IT = 100
596.73 14	(5)-	175 ps 25	100.6 1	100	M1(+E2)	496.10	(4)-
726.48 14	(6-)	51 ps 10	129.7 1 230.4 1	100.0 18 7.2 4	[M1] [E2]	596.73 496.10	(5)- (4)-
884.49 15	(7-)	45 ps 15	158.0 1 287.8 1	100.0 7 24.6 10	[M1] [E2]	726.48 596.73	(6-) (5)-
1070.70 15	(8-)	< 15 ps	186.2 1 344.2 1	100.0 13 28.8 5	[M1+E2] [E2]	884.49 726.48	(7-) (6-)
1291.76 16	(9-)		221.0 1 407.3 1	100 9 62 6		1070.70 884.49	(8-) (7-)
1532.68 17	(10-)
1842.93 21	(11-)		310.3 2 551.1 2	89 17 100 17		1532.68 1291.76	(10-) (9-)
2100.65 23	(12-)		257.7 2 568.0 2	67 13 100 20		1842.93 1532.68	(11-) (10-)
E(level) (keV)	J^π(level)	T_1/2(level)	E(γ)	I(γ)	M(γ)	Final Levels
Band 2 - πg_9/2~#νh_11/2, deformed.
564.0+X	(3-,4-)	180 ns 7
665.10+X 10			101.1 1	100		564.0+X	(3-,4-)
798.80+X 15			133.7 1	100		665.10+X
964.30+X 18			165.5 1 299?	100 10		798.80+X 665.10+X
1163.30+X 20			199.0 1 364?	100 16		964.30+X 798.80+X
1386.8+X 3			223.5 2 422.6 2 ?	100 14 23 9		1163.30+X 964.30+X
1631.5+X 4
1896.8+X 4			265.3 2	100		1631.5+X
2178.0+X 5			281.2 3	100		1896.8+X
E(level) (keV)	J^π(level)	T_1/2(level)	E(γ)	I(γ)	M(γ)	Final Levels
Band 3 - πg_9/2~#νh_11/2, spherical.
1181.50 18	(10-)	0.78 µs 3 % IT = 100
2366.0 3			1184.5 2	100		1181.50	(10-)
3165.0 4			799.0 3	100		2366.0

E(level)	J^π(level)	T_1/2(level)	Comments
0.0	0-	0.548 s 2 % β^- = 100 % β^-n = 0.33 3	δ<r²>(relative to ⁸⁹Y)=+1.088 fm² (collinear laser spectroscopy, 2007Ch07).
465.7	(7+,6+)	2.32 s 8 % β^- = 90 10 % β^-n = 3.44 95 % IT < 20	μ=+2.98 2 for J=4, +3.11 2 for J=5 (collinear laser spectroscopy, 2007Ch07, 2014StZZ); values are relative to those of ⁸⁹Y. E(level): μ=+2.98 2 for J=4, +3.11 2 for J=5 (collinear laser spectroscopy, 2007Ch07, 2014StZZ); values are relative to those of ⁸⁹Y.
496.10	(4)-	6.90 µs 5 % IT = 100	XREF: α(?). E(level): πg_9/2~#νh_11/2, Kπ=4-, prolate.
564.0+X	(3-,4-)	180 ns 7	XREF: α(?). E(level): πg_9/2~#νh_11/2, deformed.
596.73	(5)-	175 ps 25	E(level): πg_9/2~#νh_11/2, Kπ=4-, prolate.
665.10+X			E(level): πg_9/2~#νh_11/2, deformed.
713.03	(0-,1,2-)		J^π(level): 0-,1,2- from possible β feeding (allowed, first-forbidden or first-forbidden unique) from 0⁺ parent. Additional supporting comments from γ decays are given for some of the levels.
726.48	(6-)	51 ps 10	E(level): πg_9/2~#νh_11/2, Kπ=4-, prolate.
798.80+X			E(level): πg_9/2~#νh_11/2, deformed.
824.40	(0-,1,2-)		J^π(level): 0-,1,2- from possible β feeding (allowed, first-forbidden or first-forbidden unique) from 0⁺ parent. Additional supporting comments from γ decays are given for some of the levels.
884.49	(7-)	45 ps 15	E(level): πg_9/2~#νh_11/2, Kπ=4-, prolate.
908.41	(0-,1,2-)		J^π(level): 0-,1,2- from possible β feeding (allowed, first-forbidden or first-forbidden unique) from 0⁺ parent. Additional supporting comments from γ decays are given for some of the levels.
964.30+X			E(level): πg_9/2~#νh_11/2, deformed.
1070.70	(8-)	< 15 ps	E(level): πg_9/2~#νh_11/2, Kπ=4-, prolate.
1163.30+X			E(level): πg_9/2~#νh_11/2, deformed.
1181.50	(10-)	0.78 µs 3 % IT = 100	E(level): πg_9/2~#νh_11/2, spherical.
1291.76	(9-)		E(level): πg_9/2~#νh_11/2, Kπ=4-, prolate.
1348.50	(0-,1,2-)		J^π(level): 0-,1,2- from possible β feeding (allowed, first-forbidden or first-forbidden unique) from 0⁺ parent. Additional supporting comments from γ decays are given for some of the levels.
1386.8+X			E(level): πg_9/2~#νh_11/2, deformed.
1464.45	(0-,1,2-)		J^π(level): 0-,1,2- from possible β feeding (allowed, first-forbidden or first-forbidden unique) from 0⁺ parent. Additional supporting comments from γ decays are given for some of the levels.
1532.68	(10-)		E(level): πg_9/2~#νh_11/2, Kπ=4-, prolate.
1631.5+X			E(level): πg_9/2~#νh_11/2, deformed.
1680.07	(0-,1,2-)		J^π(level): 0-,1,2- from possible β feeding (allowed, first-forbidden or first-forbidden unique) from 0⁺ parent. Additional supporting comments from γ decays are given for some of the levels.
1842.93	(11-)		E(level): πg_9/2~#νh_11/2, Kπ=4-, prolate.
1896.8+X			E(level): πg_9/2~#νh_11/2, deformed.
E(level)	J^π(level)	T_1/2(level)	Comments
1898.57	(0-,1,2-)		J^π(level): 0-,1,2- from possible β feeding (allowed, first-forbidden or first-forbidden unique) from 0⁺ parent. Additional supporting comments from γ decays are given for some of the levels.
2100.65	(12-)		E(level): πg_9/2~#νh_11/2, Kπ=4-, prolate.
2178.0+X			E(level): πg_9/2~#νh_11/2, deformed.
2366.0			E(level): πg_9/2~#νh_11/2, spherical.
3165.0			E(level): πg_9/2~#νh_11/2, spherical.

E(level)	E(gamma)	Comments
119.353	119.353	E(γ): from ⁹⁸Sr β^- decay. Values from other reactions and decays are in agreement but much less precise. M(γ): also supported by δ(Q/d)=0.0 2 from γγ(θ) in SF decay (2017Ur03)
170.78	51.5	I(γ): from ²³⁵U(n,Fγ):delayed γ. Other values are in agreement but less precise
170.78	170.8	I(γ): from ²³⁵U(n,Fγ):delayed γ. Other values are in agreement but less precise
374.97	204.3	M(γ): α(K)exp in ²³⁵U,²⁴¹Pu(n,Fγ) with δ(E2/M1)>2.0 (2004Br14)
446.07	71.3	I(γ): unweighted average of 6.9 17 in ²³⁵U,²⁴¹Pu(n,Fγ) and 2.9 12 in ²³⁵U(n,Fγ):delayed γ M(γ): α(K)exp in 2004Br14 gives M1⁺E2 with δ=0.7 4 to 374, 4- level but it contradicts to 49.9γ E1 from 495, 4- level; E1⁺M2 with δ=0.5 2, but it would require an unreasonably large B(M2)(W.u.) exceeding RUL=1. So it is most probable that 71.3γ is pure E1, by combining all considerations. Note that 71.3γ is very weak (the weakest transition in 2004Br14 and 2017Ur03 also states that this transition is too weak to determine its conversion in their data including ²³⁵U(n,fγ), ²⁴⁸Cm,²⁴⁸Cf SF decay, and ⁹⁸Sr β^- decay.
496.10	49.9	I(γ): weighted average of 3.8 9 in ²³⁵U,²⁴¹Pu(n,Fγ) and 4.9 7 in ²³⁵U(n,Fγ):delayed γ
547.86	428.6	M(γ): α(K)exp in β^- decay (2002PfZZ,1988MaYY)
563.999	564.0	M(γ): α(K)exp in β^- decay (2002PfZZ,1988MaYY)
600.30	36.2	M(γ): α(K)exp and α(total)exp in β^- decay (2017Ur03,2002PfZZ,1987Ma58)
600.30	481.1	M(γ): α(K)exp in β^- decay (2002PfZZ,1988MaYY)