Zobrazeno 1 - 10
of 61
pro vyhledávání: '"Morsch HP"'
Autor:
ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BONDAR, A, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CZERWINSKI, E, DEMMICH, K, ENGELS, R, ERVENO, A, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HEIJKENSKJOLD, L, HEJNY, V, HUSKEN, N, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHATRI, G, KHOUKAZ, A, KHREPTAK, A, KIRILLOV, DA, KISTRYN, S, KLEINES, H, KLOS, B, KRZEMIEN, W, KULESSA, P, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MORSCH, HP, MOSKAL, P, OHM, H, PAROL, W, DEL RIO, EP, PISKUNOVU, NM, PRASUHN, D, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, RITMAN, J, ROY, A, RUDY, Z, RUNDEL, O, SAWANT, S, SCHADMAND, S, SCHATTI-OZERIANSKA, I, SEFZICK, T, SERDYUK, V, SHWARTZ, B, SITTERBERG, K, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TRZCINSKI, A, WOLKE, M, WRONSKA, A, WUSTNER, P, YAMAMOTO, A, ZABIEROWSKI, J, ZIELINSKI, MJ, ZLOMANCZUK, J, ZUPRANSKI, P, ZUREK, M, WILKIN, C
Publikováno v:
IndraStra Global.
New data on both total and differential cross sections of the production of eta mesons in proton-deuteron fusion to He-3 eta in the excess energy region 13.6 MeV
Autor:
ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BONDAR, A, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CZERWINSKI, E, DEMMICH, K, ENGELS, R, ERVEN, A, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSWAMI, A, GRIGORYEV, K, HEIJKENSKJOLD, L, HEJNY, V, HUSKEN, N, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHOUKAZ, A, KHREPTAK, O, KIRILLOV, DA, KISTRYN, S, KLEINES, H, KLOS, B, KRZEMIEN, W, KULESSA, P, KUPSC, A, LALWANI, K, LERSCH, D, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MORSCH, HP, MOSKAL, P, OHM, H, PAROL, W, DEL RIO, EP, PISKUNOV, NM, PRASUHN, D, PSZCZEL, D, PYSZ, K, RITMAN, J, ROY, A, RUDY, Z, RUNDEL, O, SAWANT, S, SCHADMAND, S, SCHATTI-OZERIANSKA, I, SEFZICK, T, SERDYUK, V, SHWARTZ, B, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TRZCINSKI, A, WOLKE, M, WRONSKA, A, WUSTNER, P, YAMAMOTO, A, ZABIEROWSKI, J, ZIELINSKI, MJ, ZLOMANCZUK, J, ZUPRANSKI, P, ZUREK, M
Publikováno v:
IndraStra Global.
Exclusive measurements of the quasifree pp -> pp pi(+)pi(-) reaction have been carried out at WASA@ COSY by means of pd collisions at T-p = 1.2 GeV. Total and differential cross sections have been extracted covering the energy region T-p = 1.08-1.36
Autor:
ADLARSON, R, COLLABORATION, WAC, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BONDAR, A, BUESCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CZERWINSKI, E, DEMMICH, K, ENGELS, R, ERVEN, A, ERVEN, W, EYRICH, W, FEDORETS, R, FOEHL, K, FRANSSON, K, GOLDENBAUM, F, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HEIJKENSKJOLD, L, HEJNY, V, HUESKEN, N, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHATRI, G, KHOUKAZ, A, KHREPTAK, A, KIRILLOV, DA, KISTRYN, S, KLEINES, H, KLOS, B, KRZEMIEN, W, KULESSA, R, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, R, MARIANSKI, B, MORSCH, HP, MOSKAL, R, OHM, H, PAROL, W, RIO, EP, PISKUNOV, NM, PRASUHN, D, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, RITMAN, J, ROY, A, RUDY, Z, RUNDEL, O, SAWANT, S, SCHADMAND, S, SCHATTI-OZERIANSKA, I, SEFZICK, T, SERDYUK, V, SHWARTZ, B, SITTERBERG, K, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROEHER, H, SZCZUREK, A, TRZCINSKI, A, WOLKE, M, WRONSKA, A, WUESTNER, R, YAMAMOTO, A, ZABIEROWSKI, J, ZIELINSKI, MJ, ZLOMANCZUK, J, ZUPRANSKI, R, ZUREK, M, WIRZBA, A
Publikováno v:
IndraStra Global.
We report on the search for the rare decay eta -> pi(0)e(+)e(-) which is of interest to study C violation in the electromagnetic interaction which would indicate contributions from physics beyond the Standard Model, since the allowed decay via a two-
Autor:
ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BONDAR, A, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CZERWINSKI, E, DEMMICH, K, ENGELS, R, ERVEN, A, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HANHART, C, HEIJKENSKJOLD, L, HEJNY, V, HUSKEN, N, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHATRI, G, KHOUKAZ, A, KHREPTAK, O, KIRILLOV, DA, KISTRYN, S, KLEINES, H, KLOS, B, KRZEMIEN, W, KULESSA, P, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MORSCH, HP, MOSKAL, P, OHM, H, PAROL, W, DEL RIO, EP, PISKUNOV, NM, PRASUHN, D, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, RITMAN, J, ROY, A, RUDY, Z, RUNDEL, O, SAWANT, S, SCHADMAND, S, SCHATTI-OZERIANSKA, I, SEFZICK, T, SERDYUK, V, SHWARTZ, B, SITTERBERG, K, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TRZCINSKI, A, WOLKE, M, WRONSKA, A, WUNSTNER, P, YAMAMOTO, A, ZABIEROWSKI, J, ZIELINSKI, MJ, ZLOMANCZUK, J, ZUPRANSKI, P, ZUREK, M
Publikováno v:
IndraStra Global.
This letter reports a first quantitative analysis of the contribution of higher partial waves in the charge symmetry breaking reaction dd -> He-4 pi(0) using the WASA-at-COSY detector setup at an excess energy of Q = 60 MeV. The determined differenti
Autor:
ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BONDAR, A, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CZERWINSKI, E, DEMMICH, K, ENGELS, R, ERVEN, A, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HEIJKENSKJOLD, L, HEJNY, V, HUSKEN, N, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHAN, FA, KHATRI, G, KHOUKAZ, A, KHREPTAK, O, KIRILLOV, DA, KISTRYN, S, KLEINES, H, KLOS, B, KRZEMIEN, W, KULESSA, P, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MORSCH, HP, MOSKAL, P, OHM, H, DEL RIO, EP, PISKUNOV, NM, PRASUHN, D, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, RITMAN, J, ROY, A, RUDYC, Z, RUNDEL, O, SAWANT, S, SCHADMAND, S, SCHATTI-OZERIANSKA, I, SEFZICK, T, SERDYUK, V, SHWARTZ, B, SITTERBERG, K, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TRZCINSKI, A, VARMA, R, WOLKE, M, WRONSKA, A, WUSTNER, P, YAMAMOTO, A, ZABIEROWSKI, J, ZIELINSKI, MJ, ZLOMANCZUK, J, ZUPRANSKI, P, ZUREK, M, KUBIS, B, LEUPOLD, S
Publikováno v:
IndraStra Global.
Using the production reactions pd -> He-3 omega and pp -> pp omega, the Dalitz plot distribution for the omega -> pi(+)pi(-)pi(0)decay is studied with the WASA detector at COSY, based on a combined data sample of (4.408 +/- 0.042) x 10(4) events. The
Autor:
ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BONDAR, A, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CZERWINSKI, E, DEMMICH, K, ENGELS, R, ERVEN, A, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, E, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HEIJKENSKJOLD, L, HEJNY, V, HUSKEN, N, JARCZYK, L, JOHANSSON, T, KAMYS, B, KELKAR, NG, KEMMERLING, G, KHATRI, G, KHOUKAZ, A, KHREPTAK, O, KIRILLOV, DA, KISTRYN, S, KLEINES, H, KLOS, B, KRZEMIEN, W, KULESSA, P, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LORENTZ, B, MAGIERAE, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MORSCH, HP, MOSKAL, P, OHM, H, DEL RIO, EP, PISKUNOV, NM, PRASUHN, D, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, RITMAN, J, ROY, A, RUDY, Z, RUNDEL, O, SAWANT, S, SCHADMAND, S, SCHATTI-OZERIANSKA, I, SEFZICK, T, SERDYUK, V, SHWARTZ, B, SITTERBERG, K, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TRZCINSKI, A, VARMA, R, WOLKE, M, WRONSKA, A, WUSTNER, P, YAMAMOTO, A, ZABIEROWSKI, J, ZIELINSKI, MJ, ZLOMANCZUK, J, ZUPRANSKI, P, ZUREK, M
Publikováno v:
IndraStra Global.
The search for He-4-eta bound states was performed with the WASA-at-COSY facility via the measurement of the excitation function for the dd -> (3)Hen pi(0) and dd -> (3)Hep pi(-) processes. The deuteron beam momentum was varied continuously between 2
Autor:
ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BONDAR, A, BUSCHER, M, CALEEN, H, CIEPA, I, CLEMENT, H, CZERWINSKI, E, DEMMICH, K, ENGELS, R, ERVEN, A, ERVEN, W, EYRICH, W, FEDORETS, P, FOOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HEIJKENSKJOLD, L, HEJNY, V, HUSKEN, N, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHAN, FA, KHATRI, G, KHOUKAZ, A, KIRILLOV, DA, KISTRYN, S, KLEINES, H, KLOS, B, KRZEMIEN, W, KULESSA, P, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MORSCH, HP, MOSKAL, P, OHM, H, DEL RIO, EP, PISKUNOV, NM, PRASUHN, D, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, RITMAN, J, ROY, A, RUDY, Z, RUNDEL, O, SAWANT, S, SCHADMAND, S, SCHATTI-OZERIANSKA, I, SEFZICK, T, SERDYUK, V, SHWARTZ, B, SITTERBERG, K, SIUDAK, R, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TASCHNER, A, TRZCINSKI, A, VARMA, R, WOLKE, M, WRONSKA, A, WUSTNER, P, YAMAMOTO, A, ZABIEROWSKI, J, ZIELINSKI, MJ, ZINK, A, ZLOMANCZUK, J, ZUPRANSKI, P, ZUREK, M
Publikováno v:
IndraStra Global.
We report on a high-statistics measurement of the most basic double-pionic fusion reaction over the energy region of the d (*)(2380) resonance by use of a polarized deuteron beam and observing the double fusion reaction in the quasifree scattering mo
Autor:
ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BONDAR, A, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CODERRE, D, CZERWINSKI, E, DEMMICH, K, DOROSHKEVICH, E, ENGELS, R, ERVEN, A, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSLAWSKI, P, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HAUENSTEIN, F, HEIJKENSKJOLD, L, HEJNY, V, HOISTAD, B, HUSKEN, N, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHAN, FA, KHOUKAZ, A, KIRILLOV, DA, KISTRYN, S, KLEINES, H, KLOS, B, KRZEMIEN, W, KULESSA, P, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MIKIRTYCHIANTS, M, MORSCH, HP, MOSKAL, P, OHM, H, OZERIANSKA, I, DEL RIO, EP, PISKUNOV, NM, PODKOPAL, P, PRASUHN, D, PRICKING, A, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, RITMAN, J, ROY, A, RUDY, Z, SAWANT, S, SCHADMAND, S, SEFZICK, T, SERDYUK, V, SHWARTZ, B, SIUDAK, R, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TASCHNER, A, TRZCINSKI, A, VARMA, R, WAGNER, GJ, WOLKE, M, WRONSKA, A, WUSTNER, P, WURM, P, YAMAMOTO, A, YUREV, L, ZABIEROWSKI, J, ZIELINSKI, MJ, ZINK, A, ZLOMANCZUK, J, ZUPRANSKI, P, ZUREK, M
Publikováno v:
IndraStra Global.
Exclusive and kinematically complete measurements of the double pionic fusion to He-3 have been performed in the energy region of the so-called ABC effect, which denotes a pronounced low-mass enhancement in the pi pi-invariant mass spectrum. The expe
Autor:
ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BONDAR, A, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CODERRE, D, CZERWINSKI, E, DEMMICH, K, DOROSHKEVICH, E, ENGELS, R, ERVEN, A, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, F, GOSLAWSKI, P, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HAUENSTEIN, F, HEIJKENSKJOLD, L, HEJNY, V, HODANA, M, HOISTAD, B, HUSKEN, N, JANY, A, JANY, BR, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHAN, FA, KHOUKAZ, A, KIRILLOV, DA, KISTRYN, S, KLEINES, H, KLOS, B, KRZEMIEN, W, KULESSA, P, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MARTEMYANOV, BV, MEISSNER, UG, MIKIRTYCHIANTS, M, MORSCH, HP, MOSKAL, P, OHM, H, OZERIANSKA, I, DEL RIO, EP, PISKUNOV, NM, PODKOPAL, P, PRASUHN, D, PRICKING, A, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, REDMER, CF, RITMAN, J, ROY, A, RUDY, Z, SAWANT, S, SCHADMAND, S, SEFZICK, T, SERDYUK, V, SHWARTZ, B, SIUDAK, R, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TASCHNER, A, TRZCINSKI, A, VARMA, R, WOLKE, M, WRONSKA, A, WUSTNER, P, WURM, P, YAMAMOTO, A, YUAN, X, YUREV, L, ZABIEROWSKI, J, ZHENG, C, ZIELINSKI, MJ, ZINK, A, ZLOMANCZUK, J, ZUPRANSKI, P, ZUREK, M
Publikováno v:
IndraStra Global.
The Dalitz plot distribution of the eta -> pi(+)pi(-)pi(0) decay is determined by using a data sample of 1.2 x 10(7) eta mesons from the pd -> He-3 eta reaction at 1 GeV collected by the WASA detector at COSY.
Autor:
ADLARSON, P, AUGUSTYNIAK, W, BARDAN, W, BASHKANOV, M, BERGMANN, FS, BERLOWSKI, M, BHATT, H, BONDAR, A, BUSCHER, M, CALEN, H, CIEPAL, I, CLEMENT, H, CODERRE, D, CZERWINSKI, E, DEMMICH, K, DOROSHKEVICH, E, ENGELS, R, ERVEN, W, EYRICH, W, FEDORETS, P, FOHL, K, FRANSSON, K, GOLDENBAUM, E, GOSLAWSKI, P, GOSWAMI, A, GRIGORYEV, K, GULLSTROM, CO, HAUENSTEINN, F, HEIJKENSKJOLD, L, HEJNY, V, HINTERBERGER, F, HODANA, M, HOISTAD, B, JANY, A, JANY, BR, JARCZYK, L, JOHANSSON, T, KAMYS, B, KEMMERLING, G, KHAN, FA, KHOUKAZ, A, KISTRYN, S, KLAJA, J, KLEINES, H, KIRILLOV, DA, KLOS, B, KRAPP, M, KRZEMIEN, W, KULESSA, P, KUPSC, A, KUZMIN, A, LALWANI, K, LERSCH, D, LI, L, LORENTZ, B, MAGIERA, A, MAIER, R, MARCINIEWSKI, P, MARIANSKI, B, MEISSNER, UG, MIKIRTYCHIANTS, M, MORSCH, HP, MOSKAL, P, NANDI, BK, OHM, H, OZERIANSKA, I, DEL RIO, EP, PISKUNOV, NM, PLUCINSKI, P, PODKOPAL, P, PRASUHN, D, PRICKING, A, PSZCZEL, D, PYSZ, K, PYSZNIAK, A, REDMER, CF, RITMAN, J, ROY, A, RUDY, Z, SAWANT, S, SCHADMAND, S, SCHMIDT, A, SEFZICK, T, SERDYUK, V, SHAH, N, SHWARTZ, B, SIEMASZKO, M, SIUDAK, R, SKORODKO, T, SKURZOK, M, SMYRSKI, J, SOPOV, V, STASSEN, R, STEPANIAK, J, STEPHAN, E, STERZENBACH, G, STOCKHORST, H, STROHER, H, SZCZUREK, A, TOLBA, T, TRZCINSKI, A, VARMA, R, WAGNER, GJ, WEGLORZ, W, WIRZBA, A, WOLKE, M, WRONSKA, A, WUSTNER, P, WURM, P, YAMAMOTO, A, ZABIEROWSKI, J, ZIELINSKI, MJ, ZIPPER, W, ZLOMANCZUK, J, ZUPRANSKI, P, ZUREK, M
Publikováno v:
IndraStra Global.
The presently world largest data sample for pi(0) -> gamma e(+)e(-) decays studies containing nearly 5 x 10(5) events was collected using the WASA detector at COSY. A search for a dark photon U produced in the pi(0) -> gamma U -> gamma e(+)e(-) decay