List of levels for 220RN

Authors: J.Chen, M.S. Basunia P.Dimitriou, Et Al., | Citation: Nucl. Data Sheets 212, 18 (2026) | Cutoff date: 31-Mar-2026

Historic Note: This isotope was originally called Thoron with symbol Tn.

Q-value: S(2n)=10748 3, S(2p)=12322.6 20 (2021Wa16)

E(level): From a least-squares fit to Eγ, by evaluators.

J^π(level): Individual support provided for low-lying states. Above 1150 keV, Jπ is based on assignment to either ground state or negative parity band.

M(γ): From measured matrix elements compared with theoretical predictions in Coulomb excitation, except where noted.

E(level) (keV)	J^π(level)	T_1/2(level)	E(γ) (keV)	Multipolarity	Conversion Coefficient	Additional Data
240.986	2+	0.146 ns 5	240.986 6	E2	0.276	B(E2)(W.u.)=47.4 17, α=0.276 4, α(K)=0.1109 16, α(L)=0.1220 17, α(M)=0.0324 5, α(N)=0.00843 12, α(O)=0.001724 24, α(P)=0.0002019 28
533.696	4+	46.1 ps 18	292.71 3	E2	0.1487	B(E2)(W.u.)=63.1 25, α=0.1487 21, α(K)=0.0727 10, α(L)=0.0564 8, α(M)=0.01483 21, α(N)=0.00386 5, α(O)=0.000795 11, α(P)=9.50E-5 13
645.64	1-		404.8 1	E1	0.01713	α=0.01713 24, α(K)=0.01398 20, α(L)=0.002402 34, α(M)=0.000567 8, α(N)=0.0001466 21, α(O)=3.16×10^-5 4, α(P)=4.42E-6 6
645.64	1-		645.5 1	E1	0.00663	α=0.00663 9, α(K)=0.00545 8, α(L)=0.000894 13, α(M)=0.0002097 29, α(N)=5.43×10^-5 8, α(O)=1.178E-5 16, α(P)=1.678E-6 23
663.23	(3)-		422.24 4	E1	0.01566	α=0.01566 22, α(K)=0.01279 18, α(L)=0.002187 31, α(M)=0.000516 7, α(N)=0.0001335 19, α(O)=2.88×10^-5 4, α(P)=4.03E-6 6
852.02	(5)-		188.8 5	E2	0.644	α=0.644 11, α(K)=0.1850 28, α(L)=0.339 6, α(M)=0.0908 16, α(N)=0.0236 4, α(O)=0.00481 9, α(P)=0.000551 10
852.02	(5)-		318.3 5	E1	0.0291	α=0.0291 4, α(K)=0.02360 34, α(L)=0.00417 6, α(M)=0.000985 14, α(N)=0.000255 4, α(O)=5.46×10^-5 8, α(P)=7.56E-6 11
873.90	6+	19.7 ps 20	340.2 2	E2	0.0956	B(E2)(W.u.)=74 8, α=0.0956 13, α(K)=0.0525 7, α(L)=0.0320 5, α(M)=0.00835 12, α(N)=0.002176 31, α(O)=0.000450 6, α(P)=5.48E-5 8
937.9	2+		937.8 12	E2	0.00921	α=0.00921 13, α(K)=0.00714 10, α(L)=0.001563 22, α(M)=0.000380 5, α(N)=9.89×10^-5 14, α(O)=2.124E-5 30, α(P)=2.94E-6 4
1128.2	(7)-		254.3 5	E1	0.0487	α=0.0487 7, α(K)=0.0393 6, α(L)=0.00713 11, α(M)=0.001691 25, α(N)=0.000437 6, α(O)=9.33×10^-5 14, α(P)=1.274E-5 19
1128.2	(7)-		276.2 5	[E2]	0.1778	α=0.1778 27, α(K)=0.0825 12, α(L)=0.0707 11, α(M)=0.01865 29, α(N)=0.00486 8, α(O)=0.000997 16, α(P)=0.0001184 19

Q(β-)=-870 keV 4	S(n)= 6288.7 keV 23	S(p)= 7073 keV 3	Q(α)= 6404.74 keV 10
Reference: 2021Wa16

References:
A	²²⁰At β^- decay	B	²²⁴Ra α decay
C	Coulomb Excitation	D	²³²Th(¹³⁶Xe,xγ)

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	0+	55.61 s 4 % α = 100
240.986 6	A B C D	2+	0.146 ns 5	240.986 6	100	E2	0.0	0+
533.696 31	A B C D	4+	46.1 ps 18	292.71 3	100	E2	240.986	2+
645.64 7	A B C	1-		404.8 1 645.5 1	43 7 100 9	E1 E1	240.986 0.0	2+ 0+
663.23 4	A B C D	(3)-		422.24 4	100	E1	240.986	2+
852.02 32	C D	(5)-		188.8 5 318.3 5	25 8 100 15	E2 E1	663.23 533.696	(3)- 4+
873.90 20	C D	6+	19.7 ps 20	340.2 2	100	E2	533.696	4+
937.9 8	C	2+		696.9 10 937.8 12	100 6 47 4	E2	240.986 0.0	2+ 0+
1128.2 4	C D	(7)-		254.3 5 276.2 5	41 10 100 2	E1 [E2]	873.90 852.02	6+ (5)-
1244.29 27	C D	(8+)		370.4 2	100		873.90	6+
1462.2 5	D	(9-)		217.9 5 333.9 5	14 4 100 15		1244.29 1128.2	(8+) (7)-
1631.09 34	D	(10+)		386.8 2	100		1244.29	(8+)
1834.1 7	D	(11-)		371.9 5	100		1462.2	(9-)
2033.9 6	D	(12+)		402.8 5	100		1631.09	(10+)
2227.2 8	D	(13-)		393.1 5	100		1834.1	(11-)
2452.7 8	D	(14+)		418.8 5	100		2033.9	(12+)
2638.4 10	D	(15-)		411.2 5	100		2227.2	(13-)
2887.0 9	D	(16+)		434.3 5	100		2452.7	(14+)
3068.7 11	D	(17-)		430.3 5	100		2638.4	(15-)
3325.3 11	D	(18+)		438.3 5	100		2887.0	(16+)
3509.9 12	D	(19-)		441.2 5	100		3068.7	(17-)
3763.9 12	D	(20+)		438.6 5	100		3325.3	(18+)
3961.6 13 ?	D	(21-)		451.7 5 ?	100		3509.9	(19-)

E(level) (keV)	J^π(level)	T_1/2(level)	E(γ)	I(γ)	M(γ)	Final Levels
Band 1 - Ground state rotational band.
0.0	0+	55.61 s 4 % α = 100
240.986 6	2+	0.146 ns 5	240.986 6	100	E2	0.0	0+
533.696 31	4+	46.1 ps 18	292.71 3	100	E2	240.986	2+
873.90 20	6+	19.7 ps 20	340.2 2	100	E2	533.696	4+
1244.29 27	(8+)		370.4 2	100		873.90	6+
1631.09 34	(10+)		386.8 2	100		1244.29	(8+)
2033.9 6	(12+)		402.8 5	100		1631.09	(10+)
2452.7 8	(14+)		418.8 5	100		2033.9	(12+)
2887.0 9	(16+)		434.3 5	100		2452.7	(14+)
3325.3 11	(18+)		438.3 5	100		2887.0	(16+)
3763.9 12	(20+)		438.6 5	100		3325.3	(18+)
E(level) (keV)	J^π(level)	T_1/2(level)	E(γ)	I(γ)	M(γ)	Final Levels
Band 2 - Kπ=0- γ vibrational band.
645.64 7	1-
663.23 4	(3)-		422.24 4	100	E1	240.986	2+
852.02 32	(5)-		188.8 5 318.3 5	25 8 100 15	E2 E1	663.23 533.696	(3)- 4+
1128.2 4	(7)-		254.3 5 276.2 5	41 10 100 2	E1 [E2]	873.90 852.02	6+ (5)-
1462.2 5	(9-)		217.9 5 333.9 5	14 4 100 15		1244.29 1128.2	(8+) (7)-
1834.1 7	(11-)		371.9 5	100		1462.2	(9-)
2227.2 8	(13-)		393.1 5	100		1834.1	(11-)
2638.4 10	(15-)		411.2 5	100		2227.2	(13-)
3068.7 11	(17-)		430.3 5	100		2638.4	(15-)
3509.9 12	(19-)		441.2 5	100		3068.7	(17-)
3961.6 13	(21-)		451.7 5 ?	100		3509.9	(19-)

E(level)	J^π(level)	T_1/2(level)	Comments
0.0	0+	55.61 s 4 % α = 100	E(level): From ²²⁰At β^- decay. Ground state rotational band.
240.986	2+	0.146 ns 5	E(level): From ²²⁰At β^- decay. Ground state rotational band.
533.696	4+	46.1 ps 18	E(level): From ²²⁰At β^- decay. Ground state rotational band.
645.64	1-		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
663.23	(3)-		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
852.02	(5)-		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
873.90	6+	19.7 ps 20	E(level): From ²²⁰At β^- decay. Ground state rotational band.
1128.2	(7)-		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
1244.29	(8+)		E(level): From ²²⁰At β^- decay. Ground state rotational band.
1462.2	(9-)		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
1631.09	(10+)		E(level): From ²²⁰At β^- decay. Ground state rotational band.
1834.1	(11-)		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
2033.9	(12+)		E(level): From ²²⁰At β^- decay. Ground state rotational band.
2227.2	(13-)		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
2452.7	(14+)		E(level): From ²²⁰At β^- decay. Ground state rotational band.
2638.4	(15-)		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
2887.0	(16+)		E(level): From ²²⁰At β^- decay. Ground state rotational band.
3068.7	(17-)		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
3325.3	(18+)		E(level): From ²²⁰At β^- decay. Ground state rotational band.
3509.9	(19-)		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.
3763.9	(20+)		E(level): From ²²⁰At β^- decay. Ground state rotational band.
3961.6	(21-)		E(level): From ²²⁴Ra α decay. Kπ=0- γ vibrational band.

E(level)	E(gamma)	Comments
240.986	240.986	E(γ): others: 240.97 1 in ²²⁰At β^- decay, 241.1 2 in (¹³⁶Xe,Xγ). From ²²⁴Ra α decay M(γ): from ce subshell ratios in ²²⁴Ra α decay
533.696	292.71	E(γ): others: 292.7 1 from ²²⁴Ra α decay, 292.7 2 from (¹³⁶Xe,Xγ). From ²²⁰At β^- decay
645.64	404.8	E(γ): other: 404.2 2 from ²²⁴Ra α decay. From ²²⁰At β^- decay I(γ): others: 40 9 from ²²⁴Ra α decay, 26 11 in Coulomb Excitation. From ²²⁰At β^- decay
645.64	645.5	E(γ): other: 645.6 2 in ²²⁰At β^- decay. From ²²⁴Ra α decay
663.23	422.24	E(γ): weighted average of 422.26 3 from ²²⁰At β^- decay, 422.04 10 ²²⁴Ra α decay, and 422.5 3 from (¹³⁶Xe,xγ)
937.9	696.9	E(γ): From Coulomb Excitation. I(γ): From Coulomb Excitation.
937.9	937.8	E(γ): From Coulomb Excitation. I(γ): From Coulomb Excitation.