Search for deeply bound pionic states in {sup 208}Pb via radiative atomic capture of negative pions

Journal Article · Thu May 01 04:00:00 EDT 1997 · Physical Review, C

DOI:https://doi.org/10.1103/PhysRevC.55.2492· OSTI ID:496873

Raywood, K J; Lange, J B; Jones, G; Pavan, M ^[1]; Sevior, M E ^[2]; Hutcheon, D A; Olin, A; Ottewell, D; Yen, S ^[3]; Lee, S J; Sim, K S ^[4]; Altman, A ^[5]; Friedman, E ^[6]; Trudel, A ^[7]

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1. Department of Physics, University of British Columbia, Vancouver, British Columbia, V6T 1Z1 (CANADA)
2. School of Physics, University of Melbourne, Parkville Victoria, 3052 (Australia)
3. TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3 (CANADA)
4. Department of Physics, Korea University, Seoul 136-701 (Korea)
5. Direx Medical Services, P.O. Box 4190, Petah-Tikva, 41920 (Israel)
6. Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel)
7. Simon Fraser University, Burnaby, British Columbia, V5A 1S6 (CANADA)

A search for narrow, deeply bound pionic atom states via atomic radiative capture of negative pions in a target of {sup 208}Pb was carried out for pion kinetic energies of 20 and 25 MeV. Although no clear signature of any such gamma ray emission could be observed in the data, fits of the gamma ray spectra between the energies of 12 and 42 MeV involving a quadratic background together with a pair of peaks (1s, 2p) whose relative intensity was taken from theory yielded an overall strength for the peaks which are consistent (to a 67{percent} confidence level) with radiative capture whose integrated cross section is 20.0 {plus_minus} 10.0 {mu}b/sr at 90{degree} for 20 MeV incident pions. A lower probability (40{percent} confidence level) result was obtained when the fit was carried out without the peaks included, just the continuum background. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 496873
• Journal Information: Physical Review, C, Journal Name: Physical Review, C Journal Issue: 5 Vol. 55; ISSN PRVCAN; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BOUND STATE
CAPTURE
CROSS SECTIONS
EMISSION
GAMMA RADIATION
KINETIC ENERGY
LEAD 208 TARGET
PION MINUS REACTIONS
PIONIC ATOMS
PROBABILITY
SPECTRA