19Ne(p,γ)20Naand

Radioactive ion beam physics at the cyclotron research centre Louvain-la-Neuve

“…The resonant scattering in a thick target method described in section 3.1 was first employed to investigate resonances between 650 and 1000 keV [25]. Following this, a series of experiments, all based on the detection of the decay of 20 Na, were performed RIB Physics at the CRC Louvain-la-Neuve 8 in the 1990's where more and more stringent limits were set on the resonant strength of the low-lying resonances in 20 Na [18,36,37]. These measurements suffered from a low detection efficiency (≤ 1.5%) and the presence of a background from the 19 Ne(d,n) 20 Na reaction induced by the beam on the deuterium present in the (CH 2 ) n target.…”

Constraining the 19Ne(p,γ)20Na Reaction Rate Using a Direct Measurement at DRAGON

“…However, due to the higher peak temperatures achieved in X-ray bursts, during an outburst it becomes energetically feasible to "breakout" into the rp−process; a series of sequential, rapid proton capture reactions which has been suggested to synthesise elements up to the Sn-Te mass range [6]. The reaction sequence thought to dominate breakout into the rp−process is 15 O(α, γ) 19 Ne(p, γ) 20 Na, thus the 19 Ne(p, γ) 20 Na reaction is thought to be an important factor in understanding the behaviour of Type-I X-ray bursts. Moreover, it is thought that the strength of this reaction sequence helps to determine both the conditions for ignition to occur, as well as the burst recurrence time [7].…”

“…However, for over twenty years, the exact strength and energy of this resonance state have been a subject of intense debate [8][9][10][11][12][13][14][15][16][17][18][19][20][21].…”

“…Previous direct measurements of the 19 Ne(p, γ) 20 Na reaction have utilised radioactive beams of 19 Ne [12][13][14][15][16], but none of these studies have identified the resonance of interest or measured its strength. Consequently, these studies have only been able to report upper limits of 18 meV [14], 21 meV [15], and 15 meV [16] for the resonance strength of the state of interest.…”

“…Consequently, these studies have only been able to report upper limits of 18 meV [14], 21 meV [15], and 15 meV [16] for the resonance strength of the state of interest. Additionally, Page et al [14], concluded that the dominant remaining uncertainty in the rate was the unknown spin-parity assignment of the state of interest, which had been given conflicting 1 + [8] and 3 + [9] assignments.…”