The10B(7Be,8

A. Azhari

¹

,

V. Burjan

²

,

F. Cârstoiu³

et al.

Abstract

The 10 B͑ 7 Be, 8 B͒ 9 Be reaction has been studied with an 84 MeV 7 Be radioactive beam. The measured cross section determines the asymptotic normalization coefficients for the virtual transitions 7 Be 1 p $ 8 B. These coefficients specify the amplitude of the tail of the 8 B wave function in the two-body channel 7 Be 1 p, and may be used to calculate the S factor for the direct capture reaction 7 Be͑p, g͒ 8 B at solar energies, S 17 ͑0͒. We find that S 17 ͑0͒ 17.8 6 2.8 eV b. [S0031-9007 (99)09160-7] PACS numbers: 25.60.Je, 25.60.Bx, 26.65. + t, 26.20. + f

Scattering ofBe7andB8and the astrophysicalTăbăcaru1, Azhari2, Brinkley3 et al. 2006Phys. Rev. CSelf Cite4810402View full textAdd to dashboardCite

“…This value is very close to that obtained from the 10 B( 7 Be, 8 B) 9 Be reaction in Ref. [9], which produced S 17 (0) = 18.4 ± 2.5 eV b.…”

“…The effect was to overestimate the number of secondary beam particles and hence reduce the extracted cross section and the resulting ANC. In contrast, the primary beam intensity for the 10 B( 7 Be, 8 B) 9 Be measurement [9] was sufficiently low to have a negligible effect. For the present experiment, the monitor detector was a NE102A plastic scintillator coupled to a photomultiplier tube.…”

“…In our previous experiments with a 7 Be beam [9,10], we determined the number of secondary beam particles indirectly by measuring the intensity of the 7 Li primary beam in a Faraday cup and normalizing the yield at low primary beam intensities by counting the 7 Be with the target detector. Periodically (typically once a day) the calibration procedure was repeated to check for any rate variations that were due to drifts in the MARS power supplies.…”

“…[9,10] and summarized in Ref. [12], we modified the experimental setup by adding a monitor detector to count the radioactive beam particles directly.…”

“…We previously reported measurements of the asymptotic normalization coefficients (ANCs) for 8 B that we made by using the proton transfer reactions 10 B( 7 Be, 8 B) 9 Be [9] and 14 N( 7 Be, 8 B) 13 C [10]. We determined the ANCs, which fix the amplitude of the tail of the overlap integral of the ground-state wave function of 8 B onto the two-body channel 7 Be + p, by comparing a distorted-wave Born approximation (DWBA) calculation with the angular distribution for the transfer reaction.…”