study of 22ne(6li,t 25mg three particle transfer reaction ... posters/rao_poster.pdffigure 3: delta...
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Figure 3: Delta E vs. Eres in Micromega 1 of some runs. This is used to gate on Mg.
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Delta E vs. Eres (sum) in MM1
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Delta E vs. Eres in Micromega 1
Study of 22Ne(6Li,t)25Mg three particle transfer reaction using TIARA and MDM spectrometer Esha S. Rao1,3
S. Ota1, G. Christian1, E. A. Bennett1, W.N. Catford2, S. Dede1, S. Hallam2, J. Hooker1, C. Hunt1, H. Jayatissa1, G. Lotay2, M. Moukaddam2, A. Matta2, C. Magana1, M. Mouhkaddam2, M. Muzek1, G. Rogachev1, A. Saastamoinen1, S. Upadhyayula1, R. Wilkinson2
1Cyclotron Institute, Texas A&M University, USA 2University of Surrey, Surrey, UK
3Department of Physics and Astronomy, Rutgers University, USA [email protected]
AbstractThis study provides unique insight to the structure of the states that are populated by 22Ne(6Li,t)25Mg. Furthermore, by c o n s t r u c t i n g a n a n g u l a r distribution of the 3.4 MeV state of 25Mg and comparing it to theoretical calculations [6], the spin is extracted along with the spectroscopic factor of 0.22 ± 0.04. It then seems clear that the states being populated by 25Mg have negative spin parities [1,7]. Evidently, future analysis will help to improve knowledge about 22Ne(6Li,t)25Mg.
[1] H. G. Bingham et al., Phys. Rev. C 7, 1 (1973) [2] A. Cunsolo et al., Phys. Rev. C 21, 3 (1980) [3] M. L. Avila et al., Phys. Rev. C 97, 014313 (2018) [4] M. Labiche et al., Nuclear Instruments and Method A614 (2010) [5] A. Spiridon et al., Nuclear Instruments and Methods B376 (2016) [6] I. J. Thompson, Computer Physics Report 7, 167 (1988) [7] R. A. Lindgren et al., Physical Review Letters 18, 798 (1972)
Figs. 3-6, sequentially, show how the populated states of 25Mg are identified through various gates on Delta E and the x-position of the data. To better distinguish the highest peak from 3.405 MeV (9/2+) and 3.413 MeV (3/2-), an angular distribution plot is compared with theoretical calculations using FRESCO [6] shown in Fig. 7. From Fig. 7, it seems to be that the highest peak corresponds to 3.413 MeV (3/2-). After normalization, the spectroscopic factor is determined to be 0.22 ± 0.04 for this state. This process helps to conclude that other peaks have negative spin parities as well [1,7].
Analysis
Results
Conclusion
Acknowledgements
References
Motivation
Set-Up
Figure 1: Aerial view of the TIARA detector [4] and MDM spectrometer [5].
Figure 2: TIARA detector [4] with a visual of the 22Ne(6Li,t)25Mg reaction.
I would like to thank Professor Greg Christian for giving me the opportunity to work under him this summer and the rest of the TIARA at Texas group for their support and mentorship. A special thanks to Dr. Shuya Ota without whom none of this research would have been possible. This material is based upon work funded by the National Science Foundation under Grant No. 1659847 and Department of Energy under Grant No. DE-FG02-93ER40773.
22Ne beam
25Mg
6Li target
t
Fig. 1 gives an aerial view of TIARA [4], Mult ipole-Dipole-Mu l t i po le (MDM) spectrometer [5], Oxford detector and Ge detectors. All these instruments analyze the reaction depicted in Fig. 2.
The 22Ne(6Li,t)25Mg experiment was performed in inverse kinematics using a 7A MeV 22Ne beam and 6LiF target at the Texas A&M University Cyclotron Institute. To better understand (6Li,t) three particle transfer reaction, measurements of 25Mg, t, and gamma-rays are made in coincidence using a magnetic spectrometer, Si, and Ge detectors. By doing this, the populated states of 25Mg are clearly identified thus enabling an understanding of the reaction selectivity. The angular differential cross sections are then measured to extract the spectroscopic factors. The results of this 22Ne(6Li,t)25Mg analysis are compared with data from other reaction methods and theoretical calculations to improve the knowledge about the 22Ne(6Li,t)25Mg reaction.
The (6Li,t) transfer reaction serves as a powerful tool to study 3He clustering states. Furthermore, for N=Z target nuclei (6Li,t) and (6Li,3He) are expected to populate mirror states [1] in the resulting recoil nuclei, due to the strong 3He + 3H clustering property of 6Li [2]. There is also potential to study nuclear structures by three particle transfer [3], e.g., using a radioactive ion beam, which can be a useful method for nuclear astrophysics.
Figure 7: Angular distribution of 3400 keV state in 25Mg with theoretical plots J=9/2+ and J=3/2- created by FRESCO [6].
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Figure 4: Delta E vs. Position on Wire 2 of some runs. This is used to gate on 25Mg.
25Mg
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Figure 6: 25Mg Excitation Energy of all runs. This shows the populated states of 25Mg.
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25Mg Excitation Energy
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25Mg Excitation Energy vs. Position on Wire 2
Figure 5: 25Mg Excitation Energy vs. Position on Wire 2 of some runs. This is used to gate on (6Li,t).
(6Li, t)
25Mg Excitation Energy vs. Position on Wire 2
Spin Assignment of Ex~3400 keV state from Angular Distribution
Spectroscopic Factor = 0.22 ± 0.04