List of levels for 219AT

Authors: Balraj Singh Et Al., | Citation: Nucl. Data Sheets 175, 1 (2021) | Cutoff date: 19-May-2021

1953Hy83: descendant of ²²⁷Ac. Assignment to ²¹⁹At based on chemical separation and on the genetic relationship to its α parent nucleus ²²³Fr. Measured half-life of decay of ²¹⁹At

1989Bu09: ²¹⁹At activity was produced by spallation of 600-MeV protons on targets of ²³²Th. Assignment to ²¹⁹At based on mass separation and on identification of the daughter nucleus ²¹⁵Bi in the source. The disintegration rate was determined by measuring the β^- activity with a 4π plastic scintillator detector.

2015Fi07: ²¹⁹At activity from β^- decay of ²¹⁹Po produced in ²³⁸U(p,F),E=1.4 GeV from CERN synchrotron (PS) Booster. Target=ISOLDE UC_x. Pure laser-ionized beam of ²¹⁹Po is extracted from the reaction products using a Laser-Ion Source and Trap (LIST) system, which suppresses contamination from Francium activity by more than a factor of 1000. Measured Eα and Iα of ²¹⁹At activity, branching ratio for decay of ²¹⁹At

Mass measurement: 2017Ma29: time-of-flight ion-cyclotron-resonance (ToF-ICR) technique using ISOLTRAP at ISOLDE-CERN.

2019Ba22: hyperfine structure measurements using in-source resonance ionization spectroscopy at CERN-ISOLDE. Deduced isotope shift, change in mean square charge radius, magnetic dipole and electric quadrupole moments for the ground state.

2002Sh19: analyzed levels, α-decay data, hindrance factors.

Theoretical calculations: 15 primary references in the NSR database (www.nndc.bnl.gov/nsr) related to radioactivity

All data are from ²²³Fr α decay

Q-value: S(2n)=10141 6, S(2p)=12912 18 (2021Wa16)

E(level) (keV)	J^π(level)	T_1/2(level)	E(γ) (keV)	Multipolarity	Mixing Ratio	Conversion Coefficient	Additional Data
58.9	(7/2-)		58.9 2	M1		10.87	α=10.87 19, α(L)=8.27 15, α(M)=1.96 4, α(N)=0.508 9, α(O)=0.1088 19, α(P)=0.0150 3
150.9	(5/2-)		150.9 2	E2		1.417	α=1.417, α(K)=0.287, α(L)=0.836, α(M)=0.224, α(N)=0.0578, α(O)=0.01138, α(P)=0.001171
296.2	(3/2-)		145.3 3	(M1(+E2))	0.9 LT	3.6	α=3.6 6, α(K)=2.69 69, α(L)=0.69 9, α(M)=0.17 3, α(N)=0.044 7, α(O)=0.0092 13, α(P)=0.00116 7

Q(β-)=1566.7 keV 29	S(n)= 5776 keV 12	S(p)= 5250 keV 4	Q(α)= 6342 keV 5
Reference: 2021WA16

E(level) (keV)	XREF	J^π(level)	T_1/2(level)	E(γ) (keV)	I(γ)	M(γ)	Final Levels
0.0	A	(9/2-)	56 s 4 % β^- = 6.4 10 % α = 93.6 10
58.9 2	A	(7/2-)		58.9 2	100	M1	0.0	(9/2-)
150.9 2	A	(5/2-)		150.9 2	100	E2	0.0	(9/2-)
174 5	A	(3/2-)		23 5 S			150.9	(5/2-)
296.2 4	A	(3/2-)		145.3 3	100	(M1(+E2))	150.9	(5/2-)

E(level)	J^π(level)	T_1/2(level)	Comments
0.0	(9/2-)	56 s 4 % β^- = 6.4 10 % α = 93.6 10	μ=+3.502 70 (2019Ba22), Q=-1.17 64 (2019Ba22) Based on measurements of charge radius and moments, 2019Ba22 suggest spherical configuration of πh_9/2 or π9/2[505]h_9/2, with possible octupole collectivity. Other: 2001Li44 proposed configuration=πh_9/2³~#νg_9/2^-2. E(level): Based on measurements of charge radius and moments, 2019Ba22 suggest spherical configuration of πh_9/2 or π9/2[505]h_9/2, with possible octupole collectivity. Other: 2001Li44 proposed configuration=πh_9/2³~#νg_9/2^-2.
58.9	(7/2-)		Proposed configuration=π(h_9/2²f_7/2)#νg_9/2^-2.
150.9	(5/2-)		J^π(level): Configuration may involve parts of seniority three protons, h_9/2³ and h_9/2²f_7/2, as in ²¹⁵,²¹⁷At. For 174 and 296 levels, (3/2-) is also supported by low hindrance factors (<3) in ²²³Fr α decay from 3/2(-) parent state.
174	(3/2-)		J^π(level): Configuration may involve parts of seniority three protons, h_9/2³ and h_9/2²f_7/2, as in ²¹⁵,²¹⁷At. For 174 and 296 levels, (3/2-) is also supported by low hindrance factors (<3) in ²²³Fr α decay from 3/2(-) parent state.
296.2	(3/2-)		J^π(level): Configuration may involve parts of seniority three protons, h_9/2³ and h_9/2²f_7/2, as in ²¹⁵,²¹⁷At. For 174 and 296 levels, (3/2-) is also supported by low hindrance factors (<3) in ²²³Fr α decay from 3/2(-) parent state.