Observation of the antimatter hypernucleus $${}_{\bar{{\boldsymbol{\Lambda }}}}{}^{{\bf{4}}}\bar{{\bf{H}}}$$ (2024)

Data availability

All raw data for this study were collected using the STAR detector at Brookhaven National Laboratory and are not available to the public. Derived data supporting the findings of this study are publicly available in the HEPData repository (https://www.hepdata.net/record/145132) or from the corresponding author on request.

Code availability

The codes to process raw data collected by the STAR detector are publicly available on GitHub⁷⁷ (https://github.com/star-bnl). The codes to analyse the produced data are not publicly available.

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Acknowledgements

We thank the RHIC Operations Group and RCF at BNL, the NERSC Center at LBNL, and the Open Science Grid consortium for providing resources and support. This work was supported in part by the Office of Nuclear Physics within the US DOE Office of Science, the US National Science Foundation, National Natural Science Foundation of China, Chinese Academy of Science, the Ministry of Science and Technology of China and the Chinese Ministry of Education, the Higher Education Sprout Project by Ministry of Education at NCKU, the National Research Foundation of Korea, Czech Science Foundation and Ministry of Education, Youth and Sports of the Czech Republic, Hungarian National Research, Development and Innovation Office, New National Excellency Programme of the Hungarian Ministry of Human Capacities, Department of Atomic Energy and Department of Science and Technology of the Government of India, the National Science Centre and WUT ID-UB of Poland, the Ministry of Science, Education and Sports of the Republic of Croatia, German Bundesministerium für Bildung, Wissenschaft, Forschung and Technologie (BMBF), Helmholtz Association, Ministry of Education, Culture, Sports, Science, and Technology (MEXT), Japan Society for the Promotion of Science (JSPS) and Agencia Nacional de Investigación y Desarrollo (ANID) of Chile. We thank the Joint Department for Nuclear Physics, co-founded by the Lanzhou University and Institute of Modern Physics, Chinese Academy of Sciences, for the contributions of its students J.Wu and F. Zhao to this paper.

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Author notes

Deceased: W. B. Schmidke

Authors and Affiliations

American University in Cairo, New Cairo, Egypt
M. I. Abdulhamid&A. Hamed
Texas A&M University, College Station, TX, USA
B. E. Aboona,C. A. Gagliardi,Y. Liu,S. Mioduszewski&J. Tyler
Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Prague, Czech Republic
J. Adam,J. Bielcik,J. Ceska,P. Chaloupka,A. Das,L. Holub,R. Licenik,O. Lomicky,O. Mezhanska,J. Mrazkova,S. Pal,V. Prozorova,M. Robotkova,M. Svoboda,T. Truhlar&B. A. Trzeciak
Faculty of Physics and Applied Computer Science, AGH University of Krakow, Cracow, Poland
L. Adamczyk&M. Przybycien
The Ohio State University, Columbus, OH, USA
J. R. Adams,J. D. Brandenburg,T. J. Humanic,Y. V. Khyzhniak,L. K. Kosarzewski,M. A. Lisa,X. Liu&M. Stefaniak
Panjab University, Chandigarh, India
I. Aggarwal,M. M. Aggarwal,A. Dhamija,L. Kumar,A. S. Nain,N. K. Pruthi,A. Rana&J. Singh
Variable Energy Cyclotron Centre, Kolkata, India
Z. Ahammed
Brookhaven National Laboratory, Upton, NY, USA
E. C. Aschenauer,W. Christie,X. Chu,J. C. Dunlop,O. Eyser,Y. Fisyak,W. Guryn,A. Jentsch,J. Jia,K. Kauder,A. Kiselev,J. M. Landgraf,J. Lauret,A. Lebedev,J. H. Lee,N. Lewis,R. S. Longacre,R. Ma,A. Ogawa,B. S. Page,R. Pak,L. Ruan,W. B. Schmidke,P. V. Shanmuganathan,A. H. Tang,P. Tribedy,O. D. Tsai,C. Y. Tsang,Z. Tu,T. Ullrich,G. Van Buren,J. Vanek,F. Videbæk,J. C. Webb,K. Yip,Z. Zhang,M. Zhao&M. Zurek
Indian Institute Technology, Patna, India
S. Aslam&N. Shah
Abilene Christian University, Abilene, TX, USA
J. Atchison&J. L. Drachenberg
Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile
V. Bairathi&S. Kabana
University of Houston, Houston, TX, USA
J. G. Ball Cap,R. Bellwied,C. Broodo,R. Manikandhan&A. R. Timmins
University of California, Riverside, Riverside, TX, USA
K. Barish,D. Chen,D. Kapukchyan,X. Liang,E. M. Loyd,A. Paul,C. Racz&R. Seto
University of Jammu, Jammu, India
P. Bhagat,A. Bhasin,A. Gupta,A. Jalotra&M. Sharma
State University of New York, Stony Brook, NY, USA
S. Bhatta,S. L. Huang,J. Jia,R. Lacey,N. Magdy,C. Sun&Z. Yan
ELTE Eötvös Loránd University, Budapest, Hungary
S. R. Bhosale,M. Csanád,D. Kincses&M. I. Nagy
Nuclear Physics Institute of the CAS, Rez, Czech Republic
J. Bielcikova,R. Licenik,J. Mrazkova,M. Robotkova,M. Sumbera&M. Svoboda
Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, China
X. Z. Cai
Yale University, New Haven, CT, USA
H. Caines,F. A. Flor,J. W. Harris,T. Liu,I. Mooney,D. B. Nemes,N. Smirnov,Y. Song&A. C. Tamis
University of California, Davis, Davis, CA, USA
M. Calderón de la Barca Sánchez,D. Cebra,M. D. Harasty,M. C. Labonte&Z. W. Sweger
Lawrence Berkeley National Laboratory, Berkeley, CA, USA
I. Chakaberia,X. Dong,Y. Hu,Y. Ji,H. S. Ko,G. Odyniec,A. Pandav,J. H. Thomas,H. Wieman,N. Xu&Z. Ye
University of California, Los Angeles, Los Angeles, CA, USA
B. K. Chan,Y. Cheng,H. Z. Huang,D. Neff,S. Trentalange,O. D. Tsai,G. Wang,X. Wu&Z. Xu
Indiana University, Bloomington, IN, USA
Z. Chang,W. W. Jacobs&S. W. Wissink
National Institute of Technology, Durgapur, India
A. Chatterjee
Shandong University, Qingdao, China
J. Chen,Z. Chen,T. Gao,X. Gou,Y. He,T. Lin,M. Nie,D. Shen,Y. Shi,J. Wang,X. Wang,Z. Wang,Q. H. Xu,Y. Xu,G. Yan,C. Yang,Q. Yang,L. Yi,Y. Yu,J. Zhang&Y. Zhang
Fudan University, Shanghai, China
J. H. Chen,S. Choudhury,W. He,L. Ma,Y. G. Ma,T. Shao,D. Y. Shen,Q. Y. Shou,B. Xi,C. Zhang&J. Zhao
Tsinghua University, Beijing, China
J. Cheng,X. Huang,Y. Huang,K. Kang,Y. Li,Z. Qin,Y. Wang,Z. G. Xiao&X. Zhu
University of California, Berkeley, Berkeley, CA, USA
H. J. Crawford,J. Engelage,E. G. Judd,J. M. Nelson&C. Perkins
University of Illinois at Chicago, Chicago, IL, USA
G. Dale-Gau,O. Evdokimov,T. Huang,G. Nigmatkulov,G. Wilks&Z. Zhang
University of Heidelberg, Heidelberg, Germany
I. M. Deppner,N. Herrmann,Y. H. Leung,Y. Söhngen&P. C. Weidenkaff
Indian Institute of Science Education and Research, Berhampur, India
P. Dixit,M. Nasim,A. K. Sahoo&N. Sharma
Kent State University, Kent, OH, USA
E. Duckworth,D. Keane,Y. Liang,S. Margetis,S. K. Radhakrishnan,A. I. Sheikh,C. Y. Tsang&Z. Xu
Rice University, Houston, TX, USA
G. Eppley,F. Geurts,Y. Han,C. Jin,W. Li&T. Ljubicic
University of Tsukuba, Tsukuba, Ibaraki, Japan
S. Esumi,M. Isshiki,T. Niida,T. Nonaka,K. Okubo,H. Sako,S. Sato&T. Todoroki
University of Kentucky, Lexington, KY, USA
R. Fatemi,H. Harrison-Smith,D. Kalinkin&M. A. Rosales Aguilar
University of Calabria and INFN-Cosenza, Rende, Italy
S. Fazio
National Cheng Kung University, Tainan, Taiwan
C. J. Feng,H. Huang,Y. Yang&Z. J. Zhang
Purdue University, West Lafayette, IN, USA
Y. Feng,H-S. Li,C. W. Robertson,M. J. Skoby,B. Srivastava,F. Wang&W. Xie
Southern Connecticut State University, New Haven, CT, USA
E. Finch
Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China
C. Fu,X. H. He,Q. Hu,C. Liu,T. Lu,A. K. Pandey,H. Qiu,S. Singha,X. Sun,J. Wu,X. Zhang,Y. Zhang&F. Zhao
Technische Universität Darmstadt, Darmstadt, Germany
T. Galatyuk,S. Harabasz&F-J. Seck
Temple University, Philadelphia, PA, USA
N. Ghimire,J. D. Nam,B. R. Pokhrel,M. Posik&B. Surrow
Valparaiso University, Valparaiso, IN, USA
A. Gibson,D. Grosnick,T. D. S. Stanislaus&D. G. Underwood
Indian Institute of Science Education and Research, Tirupati, India
K. Gopal,C. Jena,N. R. Sahoo,R. Sharma,S. R. Sharma&P. Sinha
University of Chinese Academy of Sciences, Beijing, China
C. Hu&G. Xie
Central China Normal University, Wuhan, China
Y. Huang,C. Li,H. Liu,L. Liu,Z. Liu,X. F. Luo,K. Mi,S. S. Shi,Y. Wang,J. Wu,Y. Xu,Y. Zhang,S. Zhou&Y. Zhou
University of Science and Technology of China, Hefei, China
X. Ju,D. Li,X. Li,Y. Li,Z. Li,J. Luo,K. Shen,F. Si,Y. Su,Y. Sun,Z. Tang,I. Upsal,K. Wang,Y. Wang,X. Wu,W. Zha,Y. Zhang&J. Zhou
Wayne State University, Detroit, MI, USA
A. Khanal,G. McNamara,J. Putschke,D. J. Stewart,V. Verkest&S. A. Voloshin
Warsaw University of Technology, Warsaw, Poland
D. P. Kikoła,D. Mallick,D. Pawlowska,J. Pluta,P. Roy Chowdhury,S. K. Tripathy,D. Wielanek&H. Zbroszczyk
Frankfurt Institute for Advanced Studies, Frankfurt, Germany
I. Kisel,I. Vassiliev&M. Zyzak
Lehigh University, Bethlehem, PA, USA
A. G. Knospe,T. Protzman,R. Reed&B. C. Schaefer
Wuhan University of Science and Technology, Wuhan, China
H. Li
Guangxi Normal University, Guilin, China
Y. Lin
South China Normal University, Guangzhou, China
G. Liu,S. Yang,Z. Ye,D. Zhang&W. Zhang
University of Texas, Austin, TX, USA
C. Markert&R. L. Ray
National Institute of Science Education and Research, Homi Bhabha National Institute, Jatni, India
B. Mohanty&M. M. Mondal
Sejong University, Seoul, South Korea
S. Oh
Rutgers University, Piscataway, NJ, USA
T. Pani,D. Roy&S. Salur
Institute of Nuclear Physics PAN, Cracow, Poland
B. Pawlik
Max-Planck-Institut für Physik, Munich, Germany
N. Schmitz&P. Seyboth
Creighton University, Omaha, NE, USA
J. Seger&D. Tlusty
Ball State University, Muncie, IN, USA
M. J. Skoby
Huzhou University, Huzhou, China
Y. Sun,J. S. Wang&H. Xu
Michigan State University, East Lansing, MI, USA
T. Tarnowsky&G. D. Westfall
Argonne National Laboratory, Argonne, IL, USA
D. G. Underwood&M. Zurek
United States Naval Academy, Annapolis, MD, USA
R. Witt
Chongqing University, Chongqing, China
S. Zhang

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Extended data figures and tables

Extended Data Fig. 1 Illustration of the decay topology of a hypernucleus and the variables for the selection criteria.

The arrows indicate the relation between variables and their corresponding geometric distances.

Extended Data Fig. 2 Reconstruction efficiency as a function of L/(βγ) obtained from the embedding Monte Carlo technique.

Hypernuclei have stricter topological cuts than antihypernuclei to suppress knock-out ³He and ⁴He, resulting in lower efficiencies.

Extended Data Fig. 3

${}_{\Lambda }{}^{3}{\rm{H}}$, ${}_{\bar{\Lambda }}{}^{3}\bar{{\rm{H}}}$, ${}_{\Lambda }{}^{4}{\rm{H}}$ and ${}_{\bar{\Lambda }}{}^{4}\bar{{\rm{H}}}$ candidate invariant-mass distributions in different L/βγ intervals.

Extended Data Fig. 4 dN/d(L/βγ) as a function of L/βγ for Λ and $\bar{\Lambda }$.

The exponential fits are applied to obtain their lifetimes.

Extended Data Fig. 5 Efficiency corrected pT spectra for 3He, ${}^{3}\bar{{\rm{He}}}$, ${}_{\Lambda }{}^{3}{\rm{H}}$, and ${}_{\bar{\Lambda }}{}^{3}\bar{{\rm{H}}}$.

The spectra are in the phase space of ∣y∣ < 0.7 with only minimum-bias triggered events. The spectra are not normalized by the number of events. The lines represent the BW-function fits.

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$Observation of the antimatter hypernucleus $${}_{\bar{{\boldsymbol{\Lambda }}}}{}^{{\bf{4}}}\bar{{\bf{H}}}$$ (1)$

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STAR Collaboration. Observation of the antimatter hypernucleus ${}_{\bar{{\boldsymbol{\Lambda }}}}{}^{{\bf{4}}}\bar{{\bf{H}}}$. Nature 632, 1026–1031 (2024). https://doi.org/10.1038/s41586-024-07823-0

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Received: 20 October 2023
Accepted: 12 July 2024
Published: 21 August 2024
Issue Date: 29 August 2024
DOI: https://doi.org/10.1038/s41586-024-07823-0

Observation of the antimatter hypernucleus $${}_{\bar{{\boldsymbol{\Lambda }}}}{}^{{\bf{4}}}\bar{{\bf{H}}}$$ (2024)

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Extended data figures and tables

Extended Data Fig. 1 Illustration of the decay topology of a hypernucleus and the variables for the selection criteria.

Extended Data Fig. 2 Reconstruction efficiency as a function of L/(βγ) obtained from the embedding Monte Carlo technique.

Extended Data Fig. 3

Extended Data Fig. 4 dN/d(L/βγ) as a function of L/βγ for Λ and \(\bar{\Lambda }\).

Extended Data Fig. 5 Efficiency corrected pT spectra for 3He, \({}^{3}\bar{{\rm{He}}}\), \({}_{\Lambda }{}^{3}{\rm{H}}\), and \({}_{\bar{\Lambda }}{}^{3}\bar{{\rm{H}}}\).

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