Search for a bound trineutron with the $^3$He($\pi^-$,$\pi^+$)nnn reaction

J. Gräter; P. A. Amaudruz; R. Bilger; P. Camerini; J. Clark; H. Clement; E. Friedman; L. Felawka; S.N. Filippov; E. Friagiacomo; Yu. K. Gavrilov; E. Gibson; N. Grion; G.J. Hofman; B. Jamieson; T.L. Karavicheva; M. Kermani; E.L. Mathie; R. Meier; G. Moloney; D. Ottewell; J. Pätzold; O. Patarakin; K. Raywood; R. Rui; M. Schepkin; M.E. Sevior; G.R. Smith; H. Staudenmaier; R. Tacik; G. Tagliente; G.J. Wagner; M. Yeomans

doi:doi:10.1007/s100500050196

2021 Impact factor 3.131

Hadrons and Nuclei

Eur. Phys. J. A 4, 5-7

Short note

Search for a bound trineutron with the ³He( $\pi^-$ , $\pi^+$ )nnn reaction

J. Gräter¹ - P. A. Amaudruz² - R. Bilger¹ - P. Camerini³ - J. Clark⁴ - H. Clement¹ - E. Friedman⁵ - L. Felawka² - S.N. Filippov⁶ - E. Friagiacomo³ - Yu. K. Gavrilov⁶ - E. Gibson⁷ - N. Grion³ - G.J. Hofman⁸ - B. Jamieson⁸ - T.L. Karavicheva⁶ - M. Kermani⁸ - E.L. Mathie⁹ - R. Meier¹ - G. Moloney⁴ - D. Ottewell² - J. Pätzold¹ - O. Patarakin¹⁰ - K. Raywood² - R. Rui³ - M. Schepkin¹¹ - M.E. Sevior⁴ - G.R. Smith² - H. Staudenmaier¹² - R. Tacik⁹ - G. Tagliente⁸ - G.J. Wagner¹ - M. Yeomans⁹

¹ Physikalisches Institut, Universität Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany
² TRIUMF, 4004 Wesbrook Mall, Vancouver BC, V6T 2A3, Canada
³ University and INFN Trieste, 34127 Trieste, Italy
⁴ School of Physics, University of Melbourne, Parkville, Victoria 3052, Australia
⁵ Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel
⁶ Institute for Nuclear Research, 117312 Moscow, Russia
⁷ California State University, 6000 J St, Sacramento, California, 95819
⁸ Department of Physics and Astronomy, University of British Columbia, Vancouver BC, V6T 2A6, Canada
⁹ University of Regina, Regina Saskatchewan S4S 0A2, Canada
¹⁰ RRC Kurchatov Institut, 123182 Moscow, Russia
¹¹ ITEP Moscow, 117218 Moscow, Russia
¹² Universität Karlsruhe, Kaiserstr. 12, 76128 Karlsruhe, Germany

Received: 22 October 1998 Communicated by B. Povh

Abstract
A search for the production of a bound trineutron state has been performed using the reaction ³He( $\pi^-$ , $\pi^+$ )nnn at incident pion energies of 65, 75, and 120 MeV. No evidence for the existence of the ³n was found, and an upper limit for the production cross section of approximately 30 nb/sr (2 $\sigma$ confidence level) was obtained.