New Measurement of the {pi}{sup 0} Radiative Decay Width

Journal Article · Fri Apr 22 00:00:00 EDT 2011 · Physical Review Letters

DOI:https://doi.org/10.1103/PHYSREVLETT.106.162303· OSTI ID:21550320

Larin, I ^[1]; McNulty, D; Prok, Y; Bernstein, A M; Kowalski, S ^[2]; Clinton, E; Martel, P; Miskimen, R; Wood, M ^[3]; Ambrozewicz, P; Ahmidouch, A; Benton, L; Danagoulian, S; Demirchyan, R; Gasparian, A; Hardy, K; Mtingwa, S; Overby, S; Payen, M; Pedroni, R ^[4]

---

1. Alikhanov Institute for Theoretical and Experimental Physics, Moscow (Russian Federation)
2. Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
3. University of Massachusetts, Amherst, Massachusetts 01003 (United States)
4. North Carolina A and T State University, Greensboro, North Carolina 27411 (United States)

High precision measurements of the differential cross sections for {pi}{sup 0} photoproduction at forward angles for two nuclei, {sup 12}C and {sup 208}Pb, have been performed for incident photon energies of 4.9-5.5 GeV to extract the {pi}{sup 0}{yields}{gamma}{gamma} decay width. The experiment was done at Jefferson Lab using the Hall B photon tagger and a high-resolution multichannel calorimeter. The {pi}{sup 0}{yields}{gamma}{gamma} decay width was extracted by fitting the measured cross sections using recently updated theoretical models for the process. The resulting value for the decay width is {Gamma}({pi}{sup 0}{yields}{gamma}{gamma})=7.82{+-}0.14(stat){+-}0.17(syst) eV. With the 2.8% total uncertainty, this result is a factor of 2.5 more precise than the current Particle Data Group average of this fundamental quantity, and it is consistent with current theoretical predictions.

• OSTI ID: 21550320
• Journal Information: Physical Review Letters, Vol. 106, Issue 16; Other Information: DOI: 10.1103/PhysRevLett.106.162303; (c) 2011 American Institute of Physics; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACCURACY
CALORIMETERS
CARBON 12
CEBAF ACCELERATOR
CURRENTS
DIFFERENTIAL CROSS SECTIONS
EV RANGE 01-10
GEV RANGE 01-10
LEAD 208
PHOTONS
PHOTOPRODUCTION
PIONS NEUTRAL
RADIATIVE DECAY
RESOLUTION
WIDTH
ACCELERATORS
BASIC INTERACTIONS
BOSONS
CARBON ISOTOPES
CROSS SECTIONS
DECAY
DIMENSIONS
ELECTROMAGNETIC INTERACTIONS
ELEMENTARY PARTICLES
ENERGY RANGE
EV RANGE
EVEN-EVEN NUCLEI
GEV RANGE
HADRONS
HEAVY NUCLEI
INTERACTIONS
ISOTOPES
LEAD ISOTOPES
LIGHT NUCLEI
LINEAR ACCELERATORS
MASSLESS PARTICLES
MEASURING INSTRUMENTS
MESONS
NUCLEI
PARTICLE DECAY
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
PIONS
PSEUDOSCALAR MESONS
STABLE ISOTOPES