High-resolution scattering experiments at the K130 cyclotron in Jyväskylä

Abstract

An experimental setup for nuclear reaction studies induced by light and heavy ions is described. It consists of a versatile Large Scattering Chamber equipped with two rotating tables for mounting detectors. A dedicated beam diagnostic system is used to monitor the energy spectrum of the beam on target. The system provides the necessary feedback for tuning of the K-130 cyclotron to reduce the energy spread of the accelerated beam by at least a factor of 3 down to about 0.3% of the nominal energy while maintaining beam currents around 20 pnA. At lower beam currents a 0.1% energy spread can be achieved. This improvement makes a significant impact on the scope of reaction studies possible to investigate at the Accelerator Laboratory of the University of Jyväskylä. Similar solutions could be adapted by other cyclotron facilities.

States of the 12N Nucleus with Increased Radii

“…The measurements were conducted at the University of Jyvskyl (Finland) using the K130 cyclotron [12] to produce a 3 He beam at E( 3 He) = 40 MeV. The 150 cm diameter Large Scattering Chamber was equipped with four ∆E − E detector telescopes, each containing two independent ∆E detectors and one common E detector.…”

“…It should be mentioned that, before starting measurements, beam monochromatization was done [12], which made it possible to diminish beam energy spreading up to three times and obtain a total energy resolution A standard expansion method was employed to obtain cross sections: the spectrum peaks were fitted with a Gaussian shape. The peak positions and widths were fixed in accordance with the world-average values, and the area under the peak was the only free parameter.…”

Possible neutron and proton halo structure in the isobaric analog states of A=12 nuclei

“…The measurements were carried out at the University of Jyväskylä (Finland) using the K130 cyclotron to produce a 3 He beam at E lab = 25 MeV. The 150-cm-diameter Large Scattering Chamber (LSC) [46] equipped with three sets of E -E detector telescopes, each containing two independent E detectors and one common E detector, was used. Each device allowed carrying out measurements at two angles.…”

“…This very good energy resolution was needed to resolve the 4 − or 2 − and 1 + states in 12 C, which was achieved with a monochromatization method described in Ref. [46]. The procedure reduces the energy spread of the native cyclotron beam by a factor of 2 to 3, hence making this measurement possible.…”

The spin-parities of the 13.35 MeV state and high-lying excited states around 20 MeV in $$^{12}$$C nucleus

“…The measurements were carried out in the 150 cm diameter Large Scattering Chamber (LSC) [31] at the Accelerator Laboratory of the University of Jyväskylä (Finland). The 3 He beam at E( 3 He) = 25 MeV was extracted from the K-130 cyclotron.…”