New Findings Hint Towards Existence of Kaonic Nuclei and Hyper-nuclei


2021-3-3

JPS Hot Topics 1, 009

https://doi.org/10.7566/JPSHT.1.009

© The Physical Society of Japan

This article is on

An event excess observed in the deeply bound region of 12C(K, p) missing-mass spectrum
(PTEP Editors' Choice)

Yudai Ichikawa, Junko Yamagata-Sekihara, Jung Keun Ahn, Yuya Akazawa, Kanae Aoki, Elena Botta, Hiroyuki Ekawa, Petr Evtoukhovitch, Alessandro Feliciello, Manami Fujita, Toshiyuki Gogami, Shoichi Hasegawa, Tomoyuki Hasegawa, Shuhei Hayakawa, Tomonori Hayakawa, Satoru Hirenzaki, Ryotaro Honda, Kenji Hosomi, Ken'ichi Imai, Wooseung Jung, Shunsuke Kanatsuki, Shin Hyung Kim, Shinji Kinbara, Kazuya Kobayashi, Jaeyong Lee, Simonetta Marcello, Koji Miwa, Taejin Moon, Tomofumi Nagae, Yoshiyuki Nakada, Manami Nakagawa, Takuya Nanamura, Megumi Naruki, Atsushi Sakaguchi, Hiroyuki Sako, Susumu Sato, Yuki Sasaki, Kotaro Shirotori, Hitoshi Sugimura, Toshiyuki Takahashi, Hirokazu Tamura, Kiyoshi Tanida, Zviadi Tsamalaidze, Mifuyu Ukai, and Takeshi O. Yamamoto
Prog. Theor. Exp. Phys. 2020, 123D01 (2020).

Scientists reveal a new feature in nuclear physics: the existence of kaonic nuclei and hyper-nuclei. These findings can enhance our understanding of nature and contribute to technological progress.


Physicists have been long intrigued by the “kaonic” nucleus, or a bound anti-kaon-nucleus system, that has been predicted theoretically but remains to be experimentally verified owing to a lack of knowledge of how deep the nuclear potential is.

Typically, particle physics experiments involve high-energy particles colliding with one another and giving rise to new particles or states. These can be detected in the form of spectral “peaks” due to events in excess of what is expected from the background. These “event excesses” are then matched with theoretical calculations to determine the identity of the particle.

In a recent study published in the journal Progress of Theoretical and Experimental Physics of the Physical Society of Japan, physicists collided highly energetic anti-kaon particles with carbon graphite and measured its spectrum with high statistics and resolution for the first time, to find the experimental signature of the kaonic nucleus. They simultaneously conducted theoretical calculations to determine the depth of the complex nucleus potential; this was done by tweaking the potential parameters to match the theoretical prediction with the measured spectra. They found that the prediction matched reasonably well with the experiment when they chose a value of -80 MeV for the real part of the potential.

However, they also observed a significant event excess for a kaon binding energy around 100 MeV, signifying a deeply bound state, which could not be accounted for by the kaonic nucleus potential parameters. They attributed its occurrence to a possible Y* nucleus state that had not been accounted for in the theoretical calculations.

These findings indicate a possible revelation of a new feature in nuclear physics: namely, the existence of kaonic nuclei and hyper-nuclei. This, in turn, can help enhance our knowledge of the fundamental aspects of nature and contribute to technological progress in the future.

An event excess observed in the deeply bound region of 12C(K, p) missing-mass spectrum
(PTEP Editors' Choice)

Yudai Ichikawa, Junko Yamagata-Sekihara, Jung Keun Ahn, Yuya Akazawa, Kanae Aoki, Elena Botta, Hiroyuki Ekawa, Petr Evtoukhovitch, Alessandro Feliciello, Manami Fujita, Toshiyuki Gogami, Shoichi Hasegawa, Tomoyuki Hasegawa, Shuhei Hayakawa, Tomonori Hayakawa, Satoru Hirenzaki, Ryotaro Honda, Kenji Hosomi, Ken'ichi Imai, Wooseung Jung, Shunsuke Kanatsuki, Shin Hyung Kim, Shinji Kinbara, Kazuya Kobayashi, Jaeyong Lee, Simonetta Marcello, Koji Miwa, Taejin Moon, Tomofumi Nagae, Yoshiyuki Nakada, Manami Nakagawa, Takuya Nanamura, Megumi Naruki, Atsushi Sakaguchi, Hiroyuki Sako, Susumu Sato, Yuki Sasaki, Kotaro Shirotori, Hitoshi Sugimura, Toshiyuki Takahashi, Hirokazu Tamura, Kiyoshi Tanida, Zviadi Tsamalaidze, Mifuyu Ukai, and Takeshi O. Yamamoto
Prog. Theor. Exp. Phys. 2020, 123D01 (2020).

Share this topic

Fields

Related Articles