Evaluation of neutron nuclear data on mercury isotopes

Figures & data

Table 1. Isotopic abundances and reaction Q-values of mercury isotopes.

	^195Hg	^196Hg	^197Hg	^198Hg	^199Hg	^200Hg	^201Hg	^202Hg	^203Hg	^204Hg
Abundances(%)	10.53 h^*	0.15	64.14 h^*	9.97	16.87	23.10	13.18	29.86	46.594 d^*	6.87
Q-values (MeV)
(n, γ)	8.898	6.786	8.485	6.663	8.029	6.230	7.754	5.995	7.493	5.669
(n, p)	2.352	0.096	1.382	−0.591	0.331	−1.481	−0.479	−2.210	−1.343	−3.258
(n, α)	10.939	8.301	9.868	7.488	8.747	6.565	7.889	5.691	6.978	4.697
(n, d)	−3.851	−4.322	−4.466	−4.878	−5.029	−5.473	−5.487	−6.009	−5.980	−6.611
(n, t)	−4.472	−6.492	−4.850	−6.693	−5.284	−6.800	−5.446	−6.984	−5.746	−7.216
(n, ^3He)	−3.378	−3.924	−4.605	−5.168	−5.984	−6.458	−7.132	−7.605	−8.388	−8.858
(n, 2n)	−6.887	−8.898	−6.786	−8.485	−6.663	−8.029	−6.230	−7.754	−5.995	−7.493
(n, np)	−6.075	−6.546	−6.690	−7.103	−7.253	−7.698	−7.712	−8.234	−8.205	−8.836
(n, nα)	2.277	2.040	1.516	1.383	0.825	0.718	0.334	0.135	−0.303	−0.514
(n, nd)	−10.729	−12.749	−11.107	−12.951	−11.541	−13.057	−11.704	−13.241	−12.004	−13.473
(n, 3n)	−16.079	−15.785	−15.684	−15.271	−15.148	−14.691	−14.259	−13.984	−13.749	−13.487
(n, 2np)	−12.954	−14.974	−13.332	−15.175	−13.766	−15.282	−13.928	−15.466	−14.228	−15.697

^*Half-lives are given for ^{195, 197, 203}Hg which are unstable.

Figure 1. Capture cross section of ²⁰²Hg in the resolved resonance region.

Table 2. Resolved and unresolved resonance regions.

Target nuclei	Resolved resonance	Unresolved resonance
^195Hg	–	3 eV– 100 keV
^196Hg	10^−5 eV– 102.85 eV	102.85 eV– 400 keV
^197Hg	–	15 eV– 100 keV
^198Hg	10^−5 eV– 459.14 eV	459.14 eV– 400 keV
^199Hg	10^−5 eV– 968.0 eV	968.0 eV– 100 keV
^200Hg	10^−5 eV– 10 keV	10 keV– 300 keV
^201Hg	10^−5 eV– 753.5 eV	753.5 eV– 100 keV
^202Hg	10^−5 eV– 20 keV	20 keV– 400 keV
^203Hg	–	400 eV– 100 keV
^204Hg	10^−5 eV– 10 keV	10 keV– 400 keV

Figure 2. Unresolved resonance region for n + ¹⁹⁷Hg.

Figure 3. Total cross section of elemental Hg.

Figure 4. Non-elastic cross section of elemental Hg.

Figure 5. Angular distributions of neutrons elastically scattered from elemental Hg.

Table 3. Optical model parameters for neutrons.

V^0R	= −34.40 − 6.18 × 10^−2A + 3.37 × 10^−4A^2 − 6.52 × 10^−7A^3 MeV
V^1R	= 0.027
V^2R	= 1.2 × 10^−4 MeV^−1
V^3R	= 3.5 × 10^−7 MeV^−2
$V_R^{\text{DISP}}$	= 94.88 MeV
Cviso	= 24.3 MeV
λR	= 1.05 × 10^− 2 + 1.63 × 10^− 4V^0R MeV^−1
$W_D^{\text{DISP}}$	= 11.0 MeV
WIDD	= 12.72 − 1.54 × 10^−2A + 7.14 × 10^−5A^2 MeV
Cwiso	= 18.0 MeV
λD	= 0.0140 MeV^−1
$W_V^{\text{DISP}}$	= 34.0 MeV
WIDV	= 105.05 − 14.13 × [1.0 + exp{(A − 100.21)/13.47}]^−1 MeV
$V_{\text{SO}}^0$	= 5.92 + 0.003A MeV
λSO	= 0.005 MeV^−1
$W_{\text{SO}}^{\text{DISP}}$	= −3.1 MeV
WIDSO	= 160.0 MeV
RR, D, V	= 1.21A^1/3 fm
aR, D, V	= 0.49 + 3.22 × 10^−3A − 2.07 × 10^−5A^2 + 4.47 × 10^−8A^3 fm
RSO	= (1.18 − 0.65A^−1/3)A^1/3 fm
aSO	= 0.59 fm

Table 4. Coupling schemes used in the interaction between neutron and target.

Target nuclei	Coupled levels^*	Deformation parameters
^195Hg	1/2^−(g.s.), 3/2^−(0.037), 5/2^−(0.053)	β2 = −0.130
^196Hg	0^+(g.s.), 2^+(0.426), 4^+(1.061), 6^+(1.785)	β2 = −0.110, β4 = −0.023
^197Hg	1/2^−(g.s.), 3/2^−(0.152), 5/2^−(0.308)	β2 = −0.130
^198Hg	0^+(g.s.), 2^+(0.412), 4^+(1.048), 6^+(1.816)	β2 = −0.110, β4 = −0.023
^199Hg	1/2^−(g.s.), 3/2^−(0.208), 5/2^−(0.414), 7/2^−(0.699)	β2 = −0.122
^200Hg	0^+(g.s.), 2^+(0.368), 4^+(0.947), 6^+(1.707)	β2 = −0.106, β4 = −0.024, β6 = −0.017
^201Hg	3/2^−(g.s.), 5/2^−(0.026), 7/2^−(0.414), 9/2^−(0.547)	β2=−0.105
^202Hg	0^+(g.s.), 2^+(0.440), 4^+(1.120), 6^+(1.989)	β2 = −0.088, β4 = −0.038
^203Hg	No coupling	–
^204Hg	0^+(g.s.), 2^+(0.437), 4^+(1.128), 6^+(2.191)	β2 = −0.069, β4 = −0.049, β6 = −0.013

^*The number in the parentheses indicates the excitation energy in MeV.

Table 5. Deformation parameters for DWBA calculations of mercury isotopes.

Mass no.	Ex (MeV)	L	βL	Mass no.	Ex (MeV)	L	βL
195	0.844	3	0.020	201	0.002	2	0.028
	0.875	3	0.023		0.032	2	0.039
196	1.696	3	0.031		0.385	2	0.048
	1.757	5	0.027	202	0.960	2	0.012
	1.841	7	0.013		1.312	4	0.040
197	0.509	3	0.020		1.644	0	0.009
198	1.087	2	0.018		1.966	5	0.033
	1.401	0	0.013	203	0.007	2	0.018
	1.636	5	0.027		0.051	2	0.025
	1.683	7	0.013		0.369	2	0.031
	1.835	4	0.049		0.592	2	0.040
	1.930	3	0.031	204	2.263	5	0.033
199	0.158	2	0.082		2.301	7	0.021
	0.404	2	0.067		2.675	3	0.089
200	1.254	2	0.015
	1.515	0	0.010
	1.851	5	0.036
	2.151	3	0.030

Table 6. Level density parameters for each nucleus.

Nuclei	a(^*)	Δ	Esh	T	E0	Em	$E_{\text{level}}^{\text{highest}}$
	1/MeV	MeV	MeV	MeV	MeV	MeV	MeV
^205Hg	23.809	0.838	−7.795	0.771	−0.981	10.703	1.395
^204Hg	23.713	1.680	−7.232	0.725	0.191	9.685	2.675
^203Hg	23.616	0.842	−6.529	0.712	−0.871	8.546	1.043
^202Hg	23.519	1.689	−5.927	0.734	−0.714	10.399	1.989
^201Hg	23.422	0.846	−5.263	0.685	−1.173	8.028	0.732
^200Hg	23.325	1.697	−4.720	0.629	0.176	7.391	2.274
^199Hg	23.228	0.851	−4.089	0.660	−1.381	7.625	0.822
^198Hg	23.131	1.706	−3.418	0.606	−0.077	7.236	2.110
^197Hg	23.033	0.855	−2.645	0.581	−0.901	6.006	0.904
^196Hg	22.936	1.714	−2.164	0.531	0.405	5.890	2.098
^195Hg	22.839	0.859	−1.303	0.517	−0.540	4.960	1.005
^194Hg	22.741	1.723	−1.041	0.427	1.165	4.247	2.374
^193Hg	22.644	0.864	−0.220	0.519	−0.866	5.258	0.375
^204Au	23.713	0.000	−6.873	0.717	−1.600	7.811	0.215
^203Au	23.616	0.842	−6.166	0.644	−0.215	6.466	1.087
^202Au	23.519	0.000	−5.862	0.688	−1.757	7.108	0.166
^201Au	23.422	0.846	−4.994	0.619	−0.457	6.218	0.810
^200Au	23.325	0.000	−4.616	0.611	−1.356	5.270	0.390
^199Au	23.228	0.851	−3.848	0.578	−0.431	5.576	1.159
^198Au	23.131	0.000	−3.422	0.604	−1.747	5.464	0.812
^197Au	23.033	0.855	−2.659	0.538	−0.378	5.039	1.231
^196Au	22.936	0.000	−2.059	0.591	−2.105	5.550	0.502
^195Au	22.839	0.859	−1.475	0.492	−0.211	4.422	1.560
^194Au	22.741	0.000	−0.842	0.356	−0.104	1.554	0.769
^193Au	22.644	0.864	−0.340	0.444	0.011	3.812	1.433
^202Pt	23.519	1.689	−5.152	0.641	0.170	7.639	0.535
^201Pt	23.422	0.846	−4.451	0.435	0.900	2.726	1.456
^200Pt	23.325	1.697	−4.153	0.611	0.132	7.147	2.258
^199Pt	23.228	0.851	−3.486	0.652	−1.577	7.628	0.474
^198Pt	23.131	1.706	−3.134	0.603	−0.154	7.247	1.944
^197Pt	23.033	0.855	−2.496	0.591	−1.093	6.292	0.965
^196Pt	22.936	1.714	−2.151	0.583	−0.239	7.037	1.992
^195Pt	22.839	0.859	−1.456	0.585	−1.366	6.400	0.875
^194Pt	22.741	1.723	−1.159	0.545	−0.056	6.437	1.992
^193Pt	22.644	0.864	−0.352	0.557	−1.327	6.020	0.692
^192Pt	22.546	1.732	−0.214	0.512	0.108	5.960	1.823
^191Pt	22.448	0.868	0.574	0.531	−1.227	5.657	0.613

Table 7. Gamma-ray strength functions for s-wave neutron in units of 10⁻⁴.

Compound nuclei	Present work	Mughabghab  [11]
^196Hg	170.0	–
^197Hg	3.980	–
^198Hg	52.17	–
^199Hg	3.935	14.3 ± 4.9
^200Hg	23.63	28.9 ± 9.1
^201Hg	2.274	–
^202Hg	35.99	16.6 ± 4.2
^203Hg	1.490	–
^204Hg	8.546	–
^205Hg	0.6681	–

Table 8. Pre-equilibrium parameters.

	C0		Knockout	Pickup
Target nuclei	(n, n′)	(n, p)	for (n, α)	for (n, α)
^195Hg	1.00	1.00	3.00	3.00
^196Hg	0.80	1.00	3.00	3.00
^197Hg	1.00	1.00	3.00	3.00
^198Hg	1.20	1.03	3.00	3.00
^199Hg	1.00	0.93	3.00	3.00
^200Hg	1.30	1.00	3.00	3.00
^201Hg	1.00	1.00	3.00	3.00
^202Hg	1.00	0.80	6.00	6.00
^203Hg	1.00	1.00	6.00	6.00
^204Hg	1.10	0.80	6.00	6.00

Figure 6. Capture cross sections of ^{198, 199, 200, 201}Hg.

Figure 7. Capture cross sections of ^{202, 204}Hg. The open symbols belong to ²⁰⁴Hg.

Figure 8. Maxwellian-averaged capture cross section of ¹⁹⁶Hg.

Figure 9. Capture cross section of ^natHg. The open and closed symbols stand for neutron and γ-ray measurements, respectively.

Figure 10. ¹⁹⁹Hg(n, n′)^199mHg reaction cross section. The data of Grudzevich et al. [45] were corrected for the ²⁰⁰Hg(n, 2n)^199mHg cross section estimated in the present work.

Figure 11. ¹⁹⁶Hg(n, 2n)¹⁹⁵Hg reaction cross section.

Figure 12. ¹⁹⁶Hg(n, 2n)^195gHg reaction cross section.

Figure 13. ¹⁹⁶Hg(n, 2n)^195mHg reaction cross section.

Figure 14. ¹⁹⁸Hg(n, 2n)¹⁹⁷Hg reaction cross section.

Figure 15. ¹⁹⁸Hg(n, 2n)^197gHg reaction cross section.

Figure 16. ¹⁹⁸Hg(n, 2n)^197mHg reaction cross section.

Figure 17. ²⁰⁰Hg(n, 2n)^199mHg reaction cross section.

Figure 18. ²⁰⁴Hg(n, 2n)²⁰³Hg reaction cross section.

Figure 19. ¹⁹⁸Hg(n, p)^198gAu reaction cross section.

Figure 20. ¹⁹⁹Hg(n, p)¹⁹⁹Au reaction cross section.

Figure 21. ²⁰⁰Hg(n, p)²⁰⁰Au reaction cross section.

Figure 22. ²⁰¹Hg(n, p)²⁰¹Au reaction cross section.

Figure 23. ²⁰²Hg(n, p)²⁰²Au reaction cross section.

Figure 24. ²⁰⁴Hg(n, p)²⁰⁴Au reaction cross section.

Figure 25. ²⁰⁰Hg(n, α)¹⁹⁷Pt reaction cross section.

Figure 26. ²⁰²Hg(n, α)¹⁹⁹Pt reaction cross section.

Figure 27. Double-differential neutron emission spectra from elemental Hg at 14 MeV.

Mughabghab SF. Atlas of neutron resonances, resonance parameters and thermal cross sections Z = 1–100. Amsterdam: Elsevier; 2006.

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