Sains Malaysiana 49(4)(2020): 877-884

http://dx.doi.org/10.17576/jsm-2020-4904-17

Halo Structure Investigation of Nucleus ⁸He via Core Deformation Parameter

(Penyelidikan Struktur Halo Nukleus ⁸He via Parameter Kecanggaan Teras)

FITRI HAKEEM M. SALIH, JOBAIDUL ISLAM, SHAHIDAN RADIMAN & KHOO KOK SIONG*

Nuclear Technology Research Centre, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

Diserahkan: 24 Julai 2019/Diterima: 23 Disember 2019

ABSTRACT

Helium-8 (⁸He) is a four neutrons halo nucleus and is the halo nucleus that attract attention to observe because it belongs to the group of light dripline nuclei. We studied the two neutrons halo nucleus of ⁸He. This halo nucleus lies on the neutron rich dripline in the nuclear landscape. Nucleus ⁸He was investigated in the Three-body Model with two different configurations (T and Y). To describe the Three-body Model, Jacobi coordinate systems for few bodies was used for this hyper-nucleus(⁸He). In this study, core(⁶He) + two valence neutrons (n + n) were considered as the Three-body. Based on the finding, theoretical data on configuration Y met a good agreement with the experimental data of binding energy and rms matter radius. While for configuration T, the data slightly differ from the experimental data. The results showed that the core deformation parameters, B2 of ⁸He were 0.12, 0.19, 0.35, 0.40, and 0.47. The binding energies -3.112 MeV, -3.416 MeV, and -3.625 MeV were calculated for the deformation parameters 0.35, 0.40, and 0.47 and rms radii 2.032 fm, 2.305 fm, and 2.39 fm were found for the deformation parameters 0.19, 0.35, and 0.4, respectively. In conclusion, ⁸He exhibits in prolate due to positive values of core deformation parameters.

Keywords: Core deformation parameter; halo nucleus; Three-body Model

ABSTRAK

Helium-8 (⁸He) adalah empat neutron nukleus halo dan nukleus halo yang menarik perhatian untuk diperhatikan kerana ia tergolong dalam kumpulan garis titisan nukleus ringan. Kami mengkaji dua neutron nukleus halo ⁸He. Nukleus halo ini terletak pada garis titisan yang kaya dengan neutron dalam landskap nuklear. Nukleus ⁸He dikaji menggunakan dua konfigurasi (T dan Y) di dalam Model Tiga-jasad. Untuk menggambarkan Model Tiga-jasad, Jacobi menyelaraskan sistem untuk beberapa badan digunakan untuk hiper-nukleus (⁸He). Dalam kajian ini, teras (⁶He) + dua neutron valens (n + n) dianggap sebagai Tiga-jasad. Berdasarkankeputusan kajian, data teori pada konfigurasi Y menghampiri dengan nilaiuji kajitenaga ikatan dan rms jejari jirim. Manakala, pada konfigurasi T, data teori didapati berbeza daripada data uji kaji. Hasil kajian menunjukkan bahawa parameter kecanggaan teras bagi, B2, ⁸He adalah 0.12, 0.19, 0.35, 0.40 dan 0.47. Kesimpulannya, ⁸He berbentuk sferoid lonjong disebabkan nilai positif parameter kecanggaan teras.

Kata kunci: Model Tiga-jasad; nukleus halo; parameter kecanggaan teras

RUJUKAN

Angeli, I. & Marinova, K.P. 2013. Table of experimental nuclear ground state charge radii: An update. Atomic Data and Nuclear Data Tables 99(1): 69-95.

Audi, G., Wapstra, A.H. & Thibault, C. 2003. The Ame 2003 atomic mass evaluation-(II). Tables, graphs and references. Nuclear Physics A 729(1): 337-676.

Bacca, S., Barnea, N. & Schwenk, A. 2012. Matter and charge radius of ⁶He in the hyperspherical-harmonics approach. Physical Review C 86(3): 034321.

Brida, I., Nunes, F.M. & Brown, B.A. 2006. Effects of deformation in the three-body structure of ¹¹Li. Nuclear Physics A 775(1-2): 23-34.

Chulkov, L.V., Aksouh, F., Bleile, A., Bochkarev, O.V., Cortina-Gil, D., Dobrovolsky, A.V., Egelhof, P., Geissel, H., Hellström, M., Isaev, N.B., Kiselev, O.A., Komkov, B.G., Matoš, M., Moroz, F.N., Münzenberg, G., Mutterer, M., Mylnikov, V.A., Neumaier, S.R. & Yatsoura, V.I. 2005. Quasi-free scattering with ^6,8He beams. Nuclear Physics A 759(1-2): 43-63.

Ershov, S.N., Grigorenko, L.V., Vaagen, J.S. & Zhukov, M.V. 2010. Halo formation and break up: Lessons and open questions. Journal of Physics G 37(6): 64026.

Frederico, T., Delfino, A., Tomio, L. & Yamashita, M.T. 2012. Universal aspects of light halo nuclei. Progess in Particle and Nuclear Physics 67(4): 939-994.

Golovkov, M.S., Grigorenko, L.V., Ter-Akopian, G.M., Fomichev, A.S., Oganessian, Y.T., Gorshkov, V.A., Krupko, S.A., Rodin, A.M., Sidorchuk, S.I., Slepnev, R.S.,   Stepantsov, S.V., Wolski, R., Pang, D.Y., Chudoba, V., Korsheninnikov, A.A., Kuzmin, E.A., Nikolskii, E.Y., Novatskii, B.G. & Zlatoustovskiy, S.V. 2009. The ⁸He and ¹⁰He spectra studied in the (t, p) reaction. Physics Letters, Section B 672(1): 22-29.

Hagino, K., Takahashi, N. & Sagawa, H. 2008. Strong dineutron correlation in ⁸He and ¹⁸C. Physical Review C 77(5): 1-9.

Hansen, P.G., Jensen, A.S. & Jonson, B. 1995. Nuclear Halos. Annual Review of Nuclear and Particle Science 45(1): 591-634.

Hiyama, E. & Kamimura, M. 2018. Study of various few-body systems using Gaussian expansion method (GEM). Frontiers of Physics 13(6): 132106.

Hiyama, E., Kamimura, M., Miyazaki, K. & Motoba, T. 1999. Γ transition in A=7 hypernuclei and a possible derivation of hypernuclear size. Physical Review C 59(5): 2351-2360.

Homyak, W.F. 1975. Single-particle shell mode. In Nuclear Structure. New York: Academic Press.

Hwash, W., Yahaya, R. & Radiman, S. 2014. Effect of core deformation on ¹⁷B halo nucleus. Physics of Atomic Nuclei 77(3): 275-281.

Hwash, W.S., Yahaya, R., Radiman, S. & Ismail, A.F. 2012. Nuclear structure of ¹⁴Be nucleus. Journal of the Korean Physical Society 61(1): 27-32.

Hwash, W.S., Yahaya, R., Radiman, S. & Islamil, A.F. 2012. Structure of two-neutron halo Nuclei, ¹¹Li. International Journal of Modern Physics E 21(07): 1250066.

Itagaki, N., Hirose, S., Otsuka, T., Okabe, S. & Ikeda, K. 2001. Triaxial deformation in ¹⁰Be. Physical Review C 65(4): 044302.

Jensen, A.S., Riisager, K., Fedorov, D.V. & Garrido, E. 2004. Structure and reactions of quantum halos. Review of Modern Physics 76(1): 215-261.

Kanada-En'yo, Y. 2007. Dineutron structure in ⁸He. Physical Review C 76(4): 1-12.

Keeley, N., Skaza, F., Lapoux, V., Alamanos, N., Auger, F., Beaumel, D., Becheva, E., Blumenfeld, Y., Delaunay, F., Drouart, A., Gillibert, A., Giot, L., Kemper, K.W., Nalpas, L., Pakou, A., Pollacco, E.C., Raabe, R., Roussel-Chomaz, P. & Wolski, R. 2007. Probing the ⁸He ground state via the ⁸He(p,t)⁶He reaction. Physics Letters, Section B 646(5-6): 222-226.

Khan, M.A. & Das, T. 2001. Investigation of halo structure of ⁶He by hyperspherical three-body method. Pramana Journal of Physics 57(4): 701-716.

Korsheninnikov, A.A., Nikoskii, E.Y., Kuzmin, E.A., Ozawa, A., Morimoto, K., Tokanai, F., Kanungo, R., Tanihata, I., Timofeyuk, N.K., Golovkov, M.S., Fomichev, A.S., Rodin, A.M., Chelnokov, M.L., Ter-Akopian, G.M., Mittig, W., Roussel-Chomaz, P., Savajols, H., Pollacco, E., Ogloblin, A.A. & Zhukov, M.V. 2003. Experimental evidence for the existence of [^H7] and for a specific structure of ⁸He. Physical Review Letters 90(8): 082501.

Lemasson, A., Navin, A., Keeley, N., Rejmund, M., Bhattachryya, S., Bazin, D., Beaumel, D., Blumenfeld, Y., Chatterjee, A., Gupta, D., de France, G., Jacquot, B., Labiche, M., Lemmon, R., Nanal, V., Nyberg, J., Pillay, R.G., Raabe, R., Ramachandran, K., Scarpaci, J.A., Simenel, C., Stefan, I. & Timis, C.N. 2010. Reactions with the double-Borromean nucleus ⁸He. Physical Review C 82(4): 044617.

Liang, Y.J., Liu, Z.H. & Zhou, H.Y. 2008. Investigations on the nuclear halo structures. International Journal of Modern Physics E 17(09): 1729-1738.

Markenroth, K., Meister, M., Eberlein, B., Aleksandrov, D., Aumann, T., Axelsson, L. & Baumann, T. 2001. ⁸He-⁶He: A comparative study of nuclear fragmentation reactions. Nuclear Physics A 679(3-4): 462-480.

Moon, C.B. 2014. A nuclear physics program at the rare isotope beams accelerator facility in Korea. AIP Advances 4: 041001.

Muller, P., Sulai, I.A., Villari, A.C.C., Alcàntara-Núñez, J.A., Alves-Condé, R., Bailey, K., Drake, G.W.F., Dubois, M., Ele´on, C., Gaubert, G., Holt, R.J., Janssens, R.V.F., Lecesne, N., Lu, Z.T., O’Connor, T.P., Saint-Laurent, M.G., Thomas, J.C. & Wang L.B. 2007. Nuclear charge radius of ⁸He. Physical Review Letters 99(25): 252501.

Nielsen, E. 2001. The three-body problem with short-range interactions. Physics Reports 347(5): 373-459.

Nunes, F.M., Thompson, I.J. & Johnson, R.C. 1996. Core excitation in one neutron halo systems. Nuclear Physics A 596(2): 171-186.

Ozawa, A., Suzuki, T. & Tanihata, I. 2001. Nuclear size and related topics. Nuclear Physics A 693(1-2): 32-62.

Pfeiffer, B. 2012. The AME 2012 atomic mass evaluation*(II). Tables, graphs and references Chinese Physics C 36(12): 1603-2014.

Raynal, J. & Revai, J. 1970. Transformation coefficients in the hyperspherical approach to the three-body problem. Il Nuovo Cimento A Series 10 68(4): 612-622.

Salih, F.H.M., Hafizad, M., Anis, M., Radiman, S. & Siong, K.K. 2018. Study of two-neutron halo structure nucleus ¹⁹B and ²²C via core deformation parameter at s-and p-states. In AIP Conference Proceedings 1940(1): 020022.

Salih, F.H.M., Lee, C.H., Radiman, S. & Khoo, K.S. 2017. Nuclear structure study of two-neutron halo nucleus ¹⁹B in microscopic cluster model. Modern Physics Letters A 32(11): 1750065.

Salih, F.H.M., Radiman, S. & Siong, K.K. 2017. Structure study of two-neutron halo nuclei, ²²C using three-body model. In AIP Conference Proceedings 1799: 040009.

Skaza, F., Lapoux, V., Keeley, N., Alamanos, N., Pollacco, E.C., Auger, F., Drouart, A., Gillibert, A., Beaumel, D., Becheva, E., Blumenfeld, Y., Delaunay, F., Giot, L., Kemper, K.W., Nalpas, L., Obertelli, A., Pakou, A., Raabe, R., Roussel-Chomaz, P., Sida, J.L., Scarpaci, J.A., Stepantsov, S. & Wolski, R. 2006. Experimental evidence for subshell closure in ⁸He and indication of a resonant state in ⁷He below 1 MeV. Physical Review C 73(4): 5-10.

Tanihata, I., Hirata, D., Kobayashi, T., Shimoura, S., Sugimoto, K. & Toki, H. 1992. Revelation of thick neutron skins in nuclei. Physics Letters B 289(3-4): 261-266.

Vaagen, J. & Gridnev, D. 2000. Borromean halo nuclei. Physica ScriptaT88(1): 209.

Wang, J.S., Shen, W.Q., Zhu, Z.Y., Feng, J., Guo, Z.Y., Zhan, W.L., Xiao, G.Q., Cai, X.Z., Fang, D.Q., Zhang, H.Y. & Ma, Y.G. 2001. RMF calculation and phenomenological formulas for the rms radii of light nuclei. Nuclear Physics A 691(3-4): 618-630.

Wurzer, J. & Hofmann, H.M. 1997. Structure of the helium isotopes ⁴He–⁸He. Physical Review C 55(2): 688-698.

Ye, Y., Yang, Z., Cao, Z., Xiao, J. & Lv, L. 2012. The ground state structure of ⁸He probed by the knockout reaction. In Proceedings of the 12^th Asia Pacific Physics Conference (APPC12) 2: 013024.

*Pengarang untuk surat-menyurat; email: khoo@ukm.edu.my