A new setup for the underground study of capture reactions

Casella, C.; Costantini, H.; Lemut, A.; Limata, B.; Bemmerer, D.; Bonetti, R.; Broggini, C.; Campajola, L.; Cocconi, P.; Corvisiero, P.; Cruz, J.; D’Onofrio, Antonio; Formicola, A.; Fülöp, Zs.; Gervino, G.; Gialanella, L.; Guglielmetti, A.; Gustavino, C.; Gyürky, György; Loiano, A; Imbriani, G.; Jesus, A.P.; Junker, M.; Musico, P.; Ordine, A.; Parodi, F.; Parolin, Mattia; Pinto, Joana; Prati, P.; Ribeiro, Joana Sousa; Roca, V.; Rogalla, Detlef; Rolfs, C.; Romano, M.; Rossi‐Alvarez, C.; Rottura, A.; Schuemann, F.; Somorjai, E.; Strieder, F.; Terrasi, F.; Trautvetter, H. P.; Vomiero, Alberto; Zavatarelli, S.

doi:10.1016/s0168-9002(02)00577-6

“…5, more details in [45]. Briefly, the α beam enters the 3 He windowless gas target [45] through a 7 mm diameter collimator and is stopped on a removable copper disk that serves as the primary catcher for the produced 7 Be and also as the hot side of a calorimeter [46]. The detector and the shield (made by a castle of lead bricks completely surrounding the gas target) are enclosed in a sealed plastic box flushed with N 2 to reduce Rn and its daughters background.…”

Section: Experimental Results From Prompt γ and Activation Measuremenmentioning

confidence: 99%

The nuclear physics of the hydrogen burning in the Sun

Formicola

¹

,

Corvisiero

²

,

Gervino

³

2016

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Abstract. Underground nuclear astrophysics focuses its efforts towards a deeper knowledge of the nuclear reactions that rule stellar evolution processes and enable the synthesis of the elements of the periodic table. Deep underground in the Gran Sasso laboratory, the cross-sections of the key reactions of the hydrogen burning have been measured right down to the energies of astrophysical interest. The main results obtained by the LUNA Collaboration are reviewed, and their contributions to the solution of the solar neutrino problem and to the age of the globular cluster are discussed.

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“…Subsequently, a windowless gas target setup and a 4π bismuth germanate (BGO) summing detector [41] have been used to study the radiative capture reaction 2 H(p, γ) 3 He, also within its solar Gamow peak [42].…”

Section: Laboratory For Underground Nuclear Astrophysics (Luna)mentioning

confidence: 99%

“…6 and 7) has been used. It is a modified version of the LUNA 2 H(p, γ) 3 He setup [41], with a 120 mm long target cell. In the experiment, a proton beam of energy E p = 80-250 keV and current up to 0.5 mA is provided by the LUNA2 400 kV accelerator and enters the target chamber through a sequence of long, narrow, water cooled apertures; the final aperture has a diameter of 7 mm, is 40 mm long and made from brass, with a copper cover on the side facing the ion beam.…”

Section: Setupmentioning

confidence: 99%

“…The intensity of the ion beam was measured with a calorimeter with constant temperature gradient [41]. The 41 mm thick copper beam stop forms the hot side of the calorimeter, that was kept at 70…”

Section: Beam Intensitymentioning

confidence: 99%

“…For the example shown in fig. 13, the detection efficiency is η γ = 0.592 ± 0.020, with the uncertainty given by the radioactive source used for the calibration (1.5%), the detector modeling (1%, [41]) and the branching ratios discussed above (1%).…”

Section: Detection Efficiencymentioning

confidence: 99%

See 2 more Smart Citations

CNO hydrogen burning studied deep underground

Bemmerer

¹

,

Confortola

²

,

Lemut

³

et al. 2006

Eur. Phys. J. A

1

0

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Abstract. In stars, four hydrogen nuclei are converted into a helium nucleus in two competing nuclear fusion processes, namely the proton-proton chain (p-p chain) and the carbon-nitrogen-oxygen (CNO) cycle. For temperatures above 20 million kelvin, the CNO cycle dominates energy production, and its rate is determined by the slowest process, the 14 N(p, γ) 15 O radiative capture reaction. This reaction proceeds through direct and resonant capture into the ground state and several excited states in 15 O. High energy data for capture into each of these states can be extrapolated to stellar energies using an R-matrix fit. The results from several recent extrapolation studies are discussed. A new experiment at the LUNA (Laboratory for Underground Nuclear Astrophysics) 400 kV accelerator in Italy's Gran Sasso laboratory measures the total cross section of the 14 N(p, γ) 15 O reaction with a windowless gas target and a 4π BGO summing detector, down to center of mass energies as low as 70 keV. After reviewing the characteristics of the LUNA facility, the main features of this experiment are discussed, as well as astrophysical scenarios where cross section data in the energy range covered have a direct impact, without any extrapolation. PACS

show abstract

CNO hydrogen burning studied deep underground

Bemmerer¹,

Confortola²,

Lemut³

et al.

The 2nd International Conference on Nuclear Physics in Astrophysics

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Abstract. In stars, four hydrogen nuclei are converted into a helium nucleus in two competing nuclear fusion processes, namely the proton-proton chain (p-p chain) and the carbon-nitrogen-oxygen (CNO) cycle. For temperatures above 20 million kelvin, the CNO cycle dominates energy production, and its rate is determined by the slowest process, the 14 N(p, γ) 15 O radiative capture reaction. This reaction proceeds through direct and resonant capture into the ground state and several excited states in 15 O. High energy data for capture into each of these states can be extrapolated to stellar energies using an R-matrix fit. The results from several recent extrapolation studies are discussed. A new experiment at the LUNA (Laboratory for Underground Nuclear Astrophysics) 400 kV accelerator in Italy's Gran Sasso laboratory measures the total cross section of the 14 N(p, γ) 15 O reaction with a windowless gas target and a 4π BGO summing detector, down to center of mass energies as low as 70 keV. After reviewing the characteristics of the LUNA facility, the main features of this experiment are discussed, as well as astrophysical scenarios where cross section data in the energy range covered have a direct impact, without any extrapolation. PACS

show abstract

A new setup for the underground study of capture reactions

Cited by 65 publications

References 10 publications

The nuclear physics of the hydrogen burning in the Sun

The nuclear physics of the hydrogen burning in the Sun

CNO hydrogen burning studied deep underground

CNO hydrogen burning studied deep underground

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