References
495
The proton and neutron effective charge for E1 transitions arising from target
recoil only is 0.375 in absolute value, as e p and e n play no role in the used model
for 7 Li(n, γ ) and 7 Be(p, γ ) reactions, respectively. The proton effective charge
allowing to reproduce experimental data is 2.5 times larger than the theoretical
proton effective charge, which is acceptable as effective charge typically varies by
about one unit compared to its bare value [2]. Effective charges e p and e n can be
as large as 1.5 and 0.95, respectively, for example, [105]. However, the neutron
effective charge needed to have the 7 Li(n, γ ) E1 cross section reproduced at small
energies would be 3–4 times the value of the theoretical neutron effective charge. It
would then exceed the previous value of 0.95. Consequently, one preferred to use a
neutron effective charge of twice its theoretical value, as it allows to obtain a good
reproduction of the E1 cross section at energies around 1 MeV. It is then the optimal
choice between having not too large a neutron effective charge, as it should not
depart significantly from its theoretical value, and reproducing the overall features
of the E1 cross section.
References
1. P.J. Brussard, P.W.M. Glaudemans, Shell Model Applications in Nuclear Spectroscopy (North
Holland, Amsterdam, 1977)
2. K.L.G. Heyde, The Nuclear Shell Model (Springer, Berlin, 1994)
3. G.R. Satchler, Direct Nuclear Reactions (Clarendon Press, Oxford, 1983)
4. N.K. Glendenning, Direct Nuclear Reactions (Academic Press, 1983)
5. B.A. Brown, B.H. Wildenthal, Ann. Rev. Nucl. Part. Sci. 38, 29 (1988)
6. P. Fröbrich, R. Lipperheide, Theory of Nuclear Reactions (Oxford Science Publications,
Clarendon Press, Oxford, 1996)
7. E. Caurier, G. Martínez-Pinedo, F. Nowacki, A. Poves, A.P. Zuker, Rev. Mod. Phys. 77, 427
(2005)
8. A. Korff, P. Haefner, C. Bäumer, A.M. van den Berg, N. Blasi, B. Davids, D. De Frenne,
R. de Leo, D. Frekers, E.W. Grewe, M.N. Harakeh, F. Hofmann, M. Hunyadi, E. Jacobs, B.C.
Junk, A. Negret, P. von Neumann-Cosel, L. Popescu, S. Rakers, A. Richter, H.J. Wörtche,
Phys. Rev. C 70, 067601 (2004)
9. C.W. Towsley, P.K. Bindal, K.I. Kubo, K.G. Nair, K. Nagatani, Phys. Rev. C 15, 281 (1977)
10. F.D. Becchetti, G.W. Greenlees, Phys. Rev. 182, 1190 (1969)
11. A.J. Koning, J.P. Delaroche, Nucl. Phys. A713, 231 (2003)
12. C. Mahaux, H. Weidenmüller, Shell-Model Approach to Nuclear Reactions (North-Holland,
Amsterdam, 1969)
13. H.W. Barz, I. Rotter, J. Höhn, Nucl. Phys. A 275, 111 (1977)
14. I. Rotter, H.W. Barz, J. Höhn, Nucl. Phys. A 297, 237 (1978)
15. J. Okołowicz, M. Płoszajczak, I. Rotter, Phys. Rep. 374, 271 (2003)
16. K. Bennaceur, F. Nowacki, J. Okołowicz, M. Płoszajczak, Nucl. Phys. A 651, 289 (1999)
17. K. Bennaceur, F. Nowacki, J. Okołowicz, M. Płoszajczak, Nucl. Phys. A 671, 203 (2000)
18. R. Shyam, K. Bennaceur, J. Okołowicz, M. Płoszajczak, Nucl. Phys. A 669, 65 (2000)
19. K. Bennaceur, N. Michel, F. Nowacki, J. Okołowicz, M. Płoszajczak, Phys. Lett. B 488, 75
(2000)
20. N. Michel, J. Okołowicz, F. Nowacki, M. Płoszajczak, Nucl. Phys. A 703, 202 (2002)
21. J. Rotureau, J. Okołowicz, M. Płoszajczak, Nucl. Phys. A 767, 13 (2006)
22. J. Okołowicz, M. Płoszajczak, R.J. Charity, L.G. Sobotka, Phys. Rev. C 97, 044303 (2018)
495
The proton and neutron effective charge for E1 transitions arising from target
recoil only is 0.375 in absolute value, as e p and e n play no role in the used model
for 7 Li(n, γ ) and 7 Be(p, γ ) reactions, respectively. The proton effective charge
allowing to reproduce experimental data is 2.5 times larger than the theoretical
proton effective charge, which is acceptable as effective charge typically varies by
about one unit compared to its bare value [2]. Effective charges e p and e n can be
as large as 1.5 and 0.95, respectively, for example, [105]. However, the neutron
effective charge needed to have the 7 Li(n, γ ) E1 cross section reproduced at small
energies would be 3–4 times the value of the theoretical neutron effective charge. It
would then exceed the previous value of 0.95. Consequently, one preferred to use a
neutron effective charge of twice its theoretical value, as it allows to obtain a good
reproduction of the E1 cross section at energies around 1 MeV. It is then the optimal
choice between having not too large a neutron effective charge, as it should not
depart significantly from its theoretical value, and reproducing the overall features
of the E1 cross section.
References
1. P.J. Brussard, P.W.M. Glaudemans, Shell Model Applications in Nuclear Spectroscopy (North
Holland, Amsterdam, 1977)
2. K.L.G. Heyde, The Nuclear Shell Model (Springer, Berlin, 1994)
3. G.R. Satchler, Direct Nuclear Reactions (Clarendon Press, Oxford, 1983)
4. N.K. Glendenning, Direct Nuclear Reactions (Academic Press, 1983)
5. B.A. Brown, B.H. Wildenthal, Ann. Rev. Nucl. Part. Sci. 38, 29 (1988)
6. P. Fröbrich, R. Lipperheide, Theory of Nuclear Reactions (Oxford Science Publications,
Clarendon Press, Oxford, 1996)
7. E. Caurier, G. Martínez-Pinedo, F. Nowacki, A. Poves, A.P. Zuker, Rev. Mod. Phys. 77, 427
(2005)
8. A. Korff, P. Haefner, C. Bäumer, A.M. van den Berg, N. Blasi, B. Davids, D. De Frenne,
R. de Leo, D. Frekers, E.W. Grewe, M.N. Harakeh, F. Hofmann, M. Hunyadi, E. Jacobs, B.C.
Junk, A. Negret, P. von Neumann-Cosel, L. Popescu, S. Rakers, A. Richter, H.J. Wörtche,
Phys. Rev. C 70, 067601 (2004)
9. C.W. Towsley, P.K. Bindal, K.I. Kubo, K.G. Nair, K. Nagatani, Phys. Rev. C 15, 281 (1977)
10. F.D. Becchetti, G.W. Greenlees, Phys. Rev. 182, 1190 (1969)
11. A.J. Koning, J.P. Delaroche, Nucl. Phys. A713, 231 (2003)
12. C. Mahaux, H. Weidenmüller, Shell-Model Approach to Nuclear Reactions (North-Holland,
Amsterdam, 1969)
13. H.W. Barz, I. Rotter, J. Höhn, Nucl. Phys. A 275, 111 (1977)
14. I. Rotter, H.W. Barz, J. Höhn, Nucl. Phys. A 297, 237 (1978)
15. J. Okołowicz, M. Płoszajczak, I. Rotter, Phys. Rep. 374, 271 (2003)
16. K. Bennaceur, F. Nowacki, J. Okołowicz, M. Płoszajczak, Nucl. Phys. A 651, 289 (1999)
17. K. Bennaceur, F. Nowacki, J. Okołowicz, M. Płoszajczak, Nucl. Phys. A 671, 203 (2000)
18. R. Shyam, K. Bennaceur, J. Okołowicz, M. Płoszajczak, Nucl. Phys. A 669, 65 (2000)
19. K. Bennaceur, N. Michel, F. Nowacki, J. Okołowicz, M. Płoszajczak, Phys. Lett. B 488, 75
(2000)
20. N. Michel, J. Okołowicz, F. Nowacki, M. Płoszajczak, Nucl. Phys. A 703, 202 (2002)
21. J. Rotureau, J. Okołowicz, M. Płoszajczak, Nucl. Phys. A 767, 13 (2006)
22. J. Okołowicz, M. Płoszajczak, R.J. Charity, L.G. Sobotka, Phys. Rev. C 97, 044303 (2018)