Gamow-Teller resonance in Be( ) reaction
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Ⅱ-1. Nuclear Physics - 31 - RIKEN Accel. Prog. Rep. 52 (2019) Gamow-Teller resonance in 14 Be(p, n) reaction J. Gao, ∗1,∗3 L. Stuhl, ∗2 M. Sasano, ∗1 Y. Hirai, ∗4 K. Yako, ∗2 T. Wakasa, ∗4 for SAMURAI30 Collaboration A charge-change (p, n) experiment, SAMURAI30, on 14 Be and 11 Li nuclei was performed on the SAMU- RAI spectrometer. 1,2) In this report, we present the status of the analysis of 14 Be(p, n) 14 B ∗ channel. We used inverse kinematics with a secondary beam of 14 Be at 198.4 MeV/nucleon and a 10 mm thick liquid hydrogen target, rotated by 45 ◦ . 3,4) The low-energy neutron detector setup, consisted of PANDORA 5) and WINDS scintillator arrays, covered the laboratory an- gular range of 47.8 ◦ to 133.9 ◦ and were employed to detect the recoil neutrons. Signals from those detec- tors were recorded by a digital data acquisition sys- tem, which was operated in parallel with the standard SAMURAI DAQ system by sharing the same trigger signal. 6) The neutron time-of-flight was measured to reconstruct the missing mass spectra. Figure 1 shows the laboratory angle vs. laboratory energy spectrum of the detected neutrons when 13 B is selected in the HODF24 hodoscope, three curves (in 0–5 MeV, 5–10 MeV, and 15–20 MeV of excitation en- ergies) evidently appeared. The left and right wings of the scintilator array are drawn seperately. The col- ored solid lines indicate the excitation energy of 14 B. The dotted lines indicate the corresponding center-of- mass angles. The signal-to-noise ratio is expected to be improved by the neutron-gamma discrimination anal- ysis. 7) Fig. 1. Kinematic correlation of neutron angle and energy when 13 B is detected downstream of SAMURAI. *1 RIKEN Nishina Center *2 Center for Nuclear Study, University of Tokyo *3 School of Physics, Peking University *4 Department of Physics, Kyushu University Fig. 2. Kinematic correlation of neutron angle and energy when 12 Be and deuteron are detected downstream of SAMURAI. Figure 2 shows the laboratory angle vs. labora- tory energy spectrum of neutrons when both 12 Be and deuteron are selected in the HODF24 hodoscope. These curves show that the 14 B excitation energy can be derived from the missing mass sprctrum of neutrons, thereby implying that our experiment was successfully performed. In the future, we will tag the other decay channels of excited 14 B and finally derive the Gamow-Teller strength. We express our gratitude to the RIKEN and CNS staff for the stable operation of the accelerators during the measurement. This work is funded by the China Scholarship Council, KAKENHI project 16H06716, the Japan Society for the Promotion of Science, and Kurata Grant from the Kurata Memorial Hitachi Sci- ence and Technology Foundation. References 1) M. Sasano et al., in this report. 2) T. Kobayashi et al., Nucl. Instrum. Methods Phys. Res. B 317, 294(2013). 3) M. Miwa et al., in this report. 4) X. Sun et al., in this report. 5) L. Stuhl et al., Nucl. Instrum. Methods Phys. Res. A 866, 164 (2017). 6) J. Gao et al., in this report. 7) Y. Hirai et al., in this report.
Transcript of Gamow-Teller resonance in Be( ) reaction
Ⅱ-1. Nuclear Physics
- 31 -
RIKEN Accel. Prog. Rep. 52 (2019)
Gamow-Teller resonance in 14Be(p,n) reaction
J. Gao,∗1,∗3 L. Stuhl,∗2 M. Sasano,∗1 Y. Hirai,∗4 K. Yako,∗2 T. Wakasa,∗4 for SAMURAI30 Collaboration
A charge-change (p,n) experiment, SAMURAI30,on 14Be and 11Li nuclei was performed on the SAMU-RAI spectrometer.1,2) In this report, we present thestatus of the analysis of 14Be(p,n)14B∗ channel.We used inverse kinematics with a secondary beam
of 14Be at 198.4 MeV/nucleon and a 10 mm thick liquidhydrogen target, rotated by 45◦.3,4) The low-energyneutron detector setup, consisted of PANDORA5) andWINDS scintillator arrays, covered the laboratory an-gular range of 47.8◦ to 133.9◦ and were employed todetect the recoil neutrons. Signals from those detec-tors were recorded by a digital data acquisition sys-tem, which was operated in parallel with the standardSAMURAI DAQ system by sharing the same triggersignal.6) The neutron time-of-flight was measured toreconstruct the missing mass spectra.
Figure 1 shows the laboratory angle vs. laboratoryenergy spectrum of the detected neutrons when 13B isselected in the HODF24 hodoscope, three curves (in0–5 MeV, 5–10 MeV, and 15–20 MeV of excitation en-ergies) evidently appeared. The left and right wingsof the scintilator array are drawn seperately. The col-ored solid lines indicate the excitation energy of 14B.The dotted lines indicate the corresponding center-of-mass angles. The signal-to-noise ratio is expected to beimproved by the neutron-gamma discrimination anal-ysis.7)
Fig. 1. Kinematic correlation of neutron angle and energy
when 13B is detected downstream of SAMURAI.
∗1 RIKEN Nishina Center∗2 Center for Nuclear Study, University of Tokyo∗3 School of Physics, Peking University∗4 Department of Physics, Kyushu University
Fig. 2. Kinematic correlation of neutron angle and energy
when 12Be and deuteron are detected downstream of
SAMURAI.
Figure 2 shows the laboratory angle vs. labora-tory energy spectrum of neutrons when both 12Be anddeuteron are selected in the HODF24 hodoscope.
These curves show that the 14B excitation energycan be derived from the missing mass sprctrum ofneutrons, thereby implying that our experiment wassuccessfully performed. In the future, we will tag theother decay channels of excited 14B and finally derivethe Gamow-Teller strength.
We express our gratitude to the RIKEN and CNSstaff for the stable operation of the accelerators duringthe measurement. This work is funded by the ChinaScholarship Council, KAKENHI project 16H06716,the Japan Society for the Promotion of Science, andKurata Grant from the Kurata Memorial Hitachi Sci-ence and Technology Foundation.
References1) M. Sasano et al., in this report.2) T. Kobayashi et al., Nucl. Instrum. Methods Phys. Res.
B 317, 294(2013).3) M. Miwa et al., in this report.4) X. Sun et al., in this report.5) L. Stuhl et al., Nucl. Instrum. Methods Phys. Res. A
866, 164 (2017).6) J. Gao et al., in this report.7) Y. Hirai et al., in this report.
