Coulomb Breakup of Nuclei—applications to Astrophysics

AstrophysicalS(E)factor of theN15(Cognata1, Romano2, Spitaleri3 et al. 2007Phys. Rev. C

“…In this context a number of indirect methods, the Coulomb dissociation [11][12][13][14][15][16], the asymptotic normalization coefficient (ANC) method [17][18][19][20][21][22][23][24][25], and the Trojan horse method (THM) [26][27][28][29][30] were developed. Some of these make use of direct reaction mechanisms, such as transfer processes (stripping and pick-up) and quasi-free reactions (knock-out reactions).…”

S17(0)Determined from the Coulomb Breakup of 83 MeV/Nucleon<

“…The disagreements among the direct measurements make an independent approach desirable. Peripheral transfer reactions that yield asymptotic normalization coefficients [3] and Coulomb breakup [4][5][6][7][8][9][10] permit the extraction of S factors with different systematic uncertainties. In the Coulomb breakup of 8 B, a virtual photon emitted by a heavy target nucleus such as Pb dissociates an incident 8 B projectile into 7 Be + p. This is the inverse of the radiative capture reaction.…”

Breakup of 8B and the 7Be(p, γ)8B reaction

“…The double differential cross-section for the Coulomb excitation of a projectile from its ground state to the continuum, with a definite multipolarity of order πλ is given by [5,6,7] …”

“…Refs. [5,6]) the measured cross-sections of this reaction to those of the radiative capture reaction b + x → a + γ. Thus, the astrophysical S-factors of the radiative capture processes can be determined from the study of break-up reactions under these conditions.…”

“…This makes the rate of the reaction 7 Be(p, γ) 8 B the most poorly known quantity in the entire nucleosynthesis chain leading to the formation of 8 B [4]. It may be noted that the rate of the 7 Be(p,γ) 8 B reaction is usually given in terms of the zero-energy astrophysical S-factor, S 17 (0).The Coulomb dissociation (CD) method provides an alternative indirect way to determine the cross sections for the radiative capture reactions at low energies [5,6,7,8,9]. In this procedure it is assumed that the break-up reaction a+Z → (b+x)+Z proceeds entirely via the electromagnetic interaction; the two nuclei a and Z do not interact strongly.…”