High- pT direct photon production at 11° in pp collisions at [formula omitted]

• Published in: Physics letters. B 1983-04, Vol.123 (5), p.367-372
• Main Authors: Åkesson, T., Albrow, M.G., Almehed, S., Batley, R., Benary, O., Bøggild, H., Botner, O., Brody, H., Burkert, V., Carossi, R., Cleland, W., Cockerill, D., Dagan, S., Dahl-Jensen, E., Dahl-Jensen, I., Damgaard, G., Di Ciaccio, A., Evans, W.M., Fabian, C.W., Frandsen, P., Frankel, S., Frati, W., Gordon, H., Goerlach, U., Hallgren, A., Hansen, K.H., Harris, M., Heck, B., Hilke, H.J., Hooper, J.E., Jarlskog, G., Jeffreys, P., Jensen, T., Kesseler, G., Killian, T., Kroeger, R., v.d. Lans, J., Lissauer, D., Lörstad, B., Lubatti, H., Ludlam, T., Mannelli, I., Markou, A., McCubbin, N.A., Meyer, F., Mjörnmark, U., Møller, R., Molzon, W., Nappi, A., Nielsen, B.S., Nilsson, A., Olsen, L.H., Oren, Y., Pierazzini, G., Rosselet, L., Rosso, E., Schindler, R.H., Schistad, B., Stumer, I., Sullivan, M., Thompson, J., Vella, E., Willis, W.J., Winik, M., Witzeling, W., Woody, C.
• Format: Article
• Language: English
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/0370-2693(83)91219-4

The production of direct photons has been measured relative to π 0's in the rapidity range 2.00 < y < 2.75 in pp collisions at s = 63 GeV at the CERN Intersecting Storage Rings. The γ/π 0 ratio increases from ⪅2% at p T = 1.5 GeV/ c to ∼8% at p T = 4.25 GeV/ c, similar to the value observed near 90°. The results indicate no strong enhancement of single-photon production due to quark bremsstrahlung in this kinematic region.