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Title: First Spectroscopy of the Near Drip-line Nucleus Mg 40

Abstract

One of the most exotic light neutron-rich nuclei currently accessible for experimental study is 40Mg , which lies at the intersection of the nucleon magic number N=28 and the neutron drip line. Low-lying excited states of 40Mg have been studied for the first time following a one-proton removal reaction from 41Al, performed at the Radioactive Isotope Beam Factory of RIKEN Nishina Center with the DALI2 γ-ray array and the ZeroDegree spectrometer. Two γ-ray transitions were observed, suggesting an excitation spectrum that shows unexpected properties as compared to both the systematics along the Z=12, N ≥ 20 Mg isotopes and available state-of-the-art theoretical model predictions. A possible explanation for the observed structure involves weak-binding effects in the low-lying excitation spectrum.

Authors:
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Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
OSTI Identifier:
1498690
DOE Contract Number:  
AC02-05CH11231
Resource Type:
Journal Article
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 122; Journal Issue: 5; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Crawford, H. L., Fallon, P., Macchiavelli, A. O., Doornenbal, P., Aoi, N., Browne, F., Campbell, C. M., Chen, S., Clark, R. M., Cortés, M. L., Cromaz, M., Ideguchi, E., Jones, M. D., Kanungo, R., MacCormick, M., Momiyama, S., Murray, I., Niikura, M., Paschalis, S., Petri, M., Sakurai, H., Salathe, M., Schrock, P., Steppenbeck, D., Takeuchi, S., Tanaka, Y. K., Taniuchi, R., Wang, H., and Wimmer, K. First Spectroscopy of the Near Drip-line Nucleus Mg40. United States: N. p., 2019. Web. doi:10.1103/PhysRevLett.122.052501.
Crawford, H. L., Fallon, P., Macchiavelli, A. O., Doornenbal, P., Aoi, N., Browne, F., Campbell, C. M., Chen, S., Clark, R. M., Cortés, M. L., Cromaz, M., Ideguchi, E., Jones, M. D., Kanungo, R., MacCormick, M., Momiyama, S., Murray, I., Niikura, M., Paschalis, S., Petri, M., Sakurai, H., Salathe, M., Schrock, P., Steppenbeck, D., Takeuchi, S., Tanaka, Y. K., Taniuchi, R., Wang, H., & Wimmer, K. First Spectroscopy of the Near Drip-line Nucleus Mg40. United States. doi:10.1103/PhysRevLett.122.052501.
Crawford, H. L., Fallon, P., Macchiavelli, A. O., Doornenbal, P., Aoi, N., Browne, F., Campbell, C. M., Chen, S., Clark, R. M., Cortés, M. L., Cromaz, M., Ideguchi, E., Jones, M. D., Kanungo, R., MacCormick, M., Momiyama, S., Murray, I., Niikura, M., Paschalis, S., Petri, M., Sakurai, H., Salathe, M., Schrock, P., Steppenbeck, D., Takeuchi, S., Tanaka, Y. K., Taniuchi, R., Wang, H., and Wimmer, K. Thu . "First Spectroscopy of the Near Drip-line Nucleus Mg40". United States. doi:10.1103/PhysRevLett.122.052501.
@article{osti_1498690,
title = {First Spectroscopy of the Near Drip-line Nucleus Mg40},
author = {Crawford, H. L. and Fallon, P. and Macchiavelli, A. O. and Doornenbal, P. and Aoi, N. and Browne, F. and Campbell, C. M. and Chen, S. and Clark, R. M. and Cortés, M. L. and Cromaz, M. and Ideguchi, E. and Jones, M. D. and Kanungo, R. and MacCormick, M. and Momiyama, S. and Murray, I. and Niikura, M. and Paschalis, S. and Petri, M. and Sakurai, H. and Salathe, M. and Schrock, P. and Steppenbeck, D. and Takeuchi, S. and Tanaka, Y. K. and Taniuchi, R. and Wang, H. and Wimmer, K.},
abstractNote = {One of the most exotic light neutron-rich nuclei currently accessible for experimental study is 40Mg , which lies at the intersection of the nucleon magic number N=28 and the neutron drip line. Low-lying excited states of 40Mg have been studied for the first time following a one-proton removal reaction from 41Al, performed at the Radioactive Isotope Beam Factory of RIKEN Nishina Center with the DALI2 γ-ray array and the ZeroDegree spectrometer. Two γ-ray transitions were observed, suggesting an excitation spectrum that shows unexpected properties as compared to both the systematics along the Z=12, N ≥ 20 Mg isotopes and available state-of-the-art theoretical model predictions. A possible explanation for the observed structure involves weak-binding effects in the low-lying excitation spectrum.},
doi = {10.1103/PhysRevLett.122.052501},
journal = {Physical Review Letters},
issn = {0031-9007},
number = 5,
volume = 122,
place = {United States},
year = {2019},
month = {2}
}

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