$\beta$-decay half-lives and $\beta$-delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb and Bi, beyond N=126

التفاصيل البيبلوغرافية
العنوان: $\beta$-decay half-lives and $\beta$-delayed neutron emission probabilities for several isotopes of Au, Hg, Tl, Pb and Bi, beyond N=126
المؤلفون: Caballero-Folch, R., Domingo-Pardo, C., Agramunt, J., Algora, A., Ameil, F., Ayyad, Y., Benlliure, J., Bowry, M., Calviño, F., Cano-Ott, D., Cortès, G., Davinson, T., Dillmann, I., Estrade, A., Evdokimov, A., Faestermann, T., Farinon, F., Galaviz, D., García, A. R., Geissel, H., Gelletly, W., Gernhäuser, R., Gómez-Hornillos, M. B., Guerrero, C., Heil, M., Hinke, C., Knöbel, R., Kojouharov, I., Kurcewicz, J., Kurz, N., Litvinov, Yu. A., Maier, L., Marganiec, J., Marta, M., Martínez, T., Montes, F., Mukha, I., Napoli, D. R., Nociforo, C., Paradela, C., Pietri, S., Podolyák, Zs., Prochazka, A., Rice, S., Riego, A., Rubio, B., Schaffner, H., Scheidenberger, Ch., Smith, K., Sokol, E., Steiger, K., Sun, B., Taín, J. L., Takechi, M., Testov, D., Weick, H., Wilson, E., Winfield, J. S., Wood, R., Woods, P. J., Yeremin, A.
المصدر: Phys. Rev. C 95, 064322 (2017)
سنة النشر: 2017
المجموعة: Nuclear Experiment
مصطلحات موضوعية: Nuclear Experiment
الوصف: $Background:$ Previous measurements of $\beta$-delayed neutron emitters comprise around 230 nuclei, spanning from the $^{8}$He up to $^{150}$La. Apart from $^{210}$Tl, with a minuscule branching ratio of 0.007\%, no other neutron emitter is measured yet beyond $A=150$. Therefore new data are needed, particularly in the heavy mass region around N=126, in order to guide theoretical models and to understand the formation of the third r-process peak at $A\sim195$. $Purpose:$ To measure both, $\beta$-decay half-lives and neutron branching ratios of several neutron-rich Au, Hg, Tl, Pb and Bi isotopes beyond $N=126$. $Method:$ Ions of interest are produced by fragmentation of a $^{238}$U beam, selected and identified via the GSI-FRS fragment separator. A stack of segmented silicon detectors (SIMBA) is used to measure ion-implants and $\beta$-decays. An array of 30 $^3$He tubes embedded in a polyethylene matrix (BELEN) is used to detect neutrons with high efficiency and selectivity. A self-triggered digital system is employed to acquire data and to enable time-correlations. The latter are analyzed with an analytical model and results for the half-lives and neutron-branching ratios are derived using the binned Maximum-Likelihood method. $Results:$ Twenty new $\beta$-decay half-lives are reported for $^{204-206}$Au, $^{208-211}$Hg,$^{211-216}$Tl,$^{215-218}$Pb and $^{218-220}$Bi, nine of them for the first time. Neutron emission probabilities are reported for $^{210,211}$Hg and $^{211-216}$Tl. $Conclusions:$ The new $\beta$-decay half-lives are in good agreement with previous measurements in this region. The measured neutron emission probabilities are comparable or smaller than values predicted by global models like RHB+RQRPA.
Comment: 17 pages, 21 figures, will be submitted at PRC
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevC.95.064322
URL الوصول: http://arxiv.org/abs/1701.03845
رقم الأكسشن: edsarx.1701.03845
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevC.95.064322