Evidence for anomalous prompt photons in deep inelastic muon scattering at 200 GeV

• Published in: Physics letters. B Vol. 218; no. 2; pp. 248 - 256
• Main Authors: Aubert, J.J., Bassompierre, G., Becks, K.H., Benchouk, C., Best, C., Böhm, E., De Bouard, X., Brasse, F.W., Broll, C., Brown, S.C., Carr, J., Clifft, R., Cobb, J.H., Coignet, G., Combley, F., Court, G.R., D'Agostini, G., Dau, W.D., Davies, J.K., Déclais, Y., Dosselli, U., Drees, J., Edwards, A., Edwards, M., Favier, J., Ferrero, M.I., Flauger, W., Forsbach, H., Gabathuler, E., Gamet, R., Gayler, J., Gerhardt, V., Gössling, C., Gregory, P., Haas, J., Hamacher, K., Hayman, P., Henckes, M., Ingelman, G., Korbel, V., Landgraf, U., Leenen, M., Maire, M., Mohr, W., Montgomery, H.E., Moser, K., Muont, R.P., Nagy, E., Nassalski, J., Norton, P.R., McNicholas, J., Osborne, A.M., Payre, P., Peroni, C., Pessard, H., Pietrzyk, U., Rith, K., Schneegans, M., Sloan, T., Stier, H.E., Stockhausen, W., Thénard, J.M., Thompson, J.C., Urban, L., Wahlen, H., Whalley, M., Williams, D., Williams, W.S.C., Williamson, J., Wimpenny, S.J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 16.02.1989; Elsevier
• Subjects: High Energy Physics - Experiment; Physics
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/0370-2693(89)91428-7

The inclusive yield of photons has been measured from deep inelastic interactions of 200 GeV muons on hydrogen. After subtracting the contributions from hadron electromagnetic decays and Bethe-Heitler muon bremsstrahlung, residual photons are observed at low p T and low z at a mean level of 0.15±0.06 per interaction. The quark Compton scattering process is unable to explain the data, thus indicating an anomalous photon production.