Evidence for <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi mathvariant="italic">ρ</mi></mrow><mrow><mn>0</mn></mrow></msup></mrow></math></span> Mass Modification in the <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow></mrow><mrow><mn>3</mn></mrow></msup></mrow><mi>He</mi><mo>(</mo><mi mathvariant="italic">γ</mi><mo>,</mo><mrow><msup><mrow><mi>ρ</mi></mrow><mrow><mn>0</mn></mrow></msup></mrow><mo>)</mo><mi mathvariant="italic">ppn</mi></math></span> Reaction

TAGX Collaboration; G. J. Lolos; G. M. Huber; Z. Papandreou; F. Farzanpay; M. Iurescu; A. Weinerman; G. Garino; K. Maruyama; K. Maeda; A. Shinozaki; T. Terasawa; H. Yamazaki; T. Emura; H. Hirosawa; K. Niwa; H. Yamashita; S. Endo; K. Miyamoto; Y. Sumi; A. Leone; R. Perrino; T. Maki; A. Sasaki; Y. Wada

doi:10.1103/PhysRevLett.80.241

Evidence for $ρ^{0}$ Mass Modification in the $^{3} He (γ, ρ^{0}) ppn$ Reaction

G. J. Lolos, G. M. Huber, Z. Papandreou, F. Farzanpay, M. Iurescu, A. Weinerman, G. Garino, K. Maruyama, K. Maeda, A. Shinozaki, T. Terasawa, H. Yamazaki, T. Emura, H. Hirosawa, K. Niwa, H. Yamashita, S. Endo, K. Miyamoto, Y. Sumi, A. Leone, R. Perrino, T. Maki, A. Sasaki, and Y. Wada (TAGX Collaboration)

Phys. Rev. Lett. 80, 241 – Published 12 January 1998

Abstract

Evidence for a modification of the $ρ^{0}$ mass in the nuclear medium via the $^{3} He (γ, π^{+} π^{-}) X$ reaction is reported here. The tagged photon energies were mostly below the $ρ^{0}$ production threshold on a free nucleon, and the bound nucleon's Fermi momentum was utilized to produce the $ρ^{0}$ . The mass shift observed is $δ m_{ρ^{0}} = 160 \pm 35 MeV {/ c}^{2}$ and is significantly larger than theoretical model predictions for this nucleus and nuclear matter density.

Received 13 June 1997

DOI:https://doi.org/10.1103/PhysRevLett.80.241

Authors & Affiliations

G. J. Lolos¹, G. M. Huber¹, Z. Papandreou¹, F. Farzanpay¹, M. Iurescu¹, A. Weinerman¹, G. Garino², K. Maruyama², K. Maeda³, A. Shinozaki^1,3, T. Terasawa³, H. Yamazaki³, T. Emura⁴, H. Hirosawa⁴, K. Niwa⁴, H. Yamashita⁴, S. Endo⁵, K. Miyamoto⁵, Y. Sumi⁵, A. Leone⁶, R. Perrino⁶, T. Maki⁷, A. Sasaki⁸, and Y. Wada⁹ (TAGX Collaboration)

¹Department of Physics, University of Regina, Regina, Saskatchewan, S4S 0A2 Canada
²Institute for Nuclear Study, University of Tokyo, Tanashi, Tokyo 188, Japan
³Department of Physics, Tohoku University, Sendai 980, Japan
⁴Department of Applied Physics, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184, Japan
⁵Department of Physics, Hiroshima University, Higashi-Hiroshima 724, Japan
⁶INFN-Sezione di Lecce, I-73100 Lecce, Italy
⁷University of Occupational and Environmental Health, Kitakyushu 807, Japan
⁸College of General Education, Akita University, Akita 010,Japan
⁹Meiji College of Pharmacy, Setagaya, Tokyo 154, Japan