The inclusive production of D*(+/-) mesons in photon-photon collisions has been measured by the Aleph experiment at LEP with a beam energy of 45 GeV. The D*(+) are detected in their decay to D-0 pi(+) with the D-0 observed in three separate decay modes: (1) K(-)pi(+), (2) K(-)pi(+)pi(0) and (3) K(-)pi(+)pi(-)pi(+), and analagously for the D*(-) modes. A total of 33 events was observed from an integrated luminosity of 73 pb(-1) which corresponds to a cross section for sigma(e(+)e(-) --> e(+)e(-)D*(+/-)X) of 155+/-33+/-21 pb, This result is compatible with both the direct production gamma gamma --> in the Born approximation and with a more complete calculation which includes both radiative QCD corrections and contributions in which one of the photons is first resolved into its quark and gluon constituents. The shapes of distributions for events containing a D*(+) are found to be better described by the latter.
MEASUREMENT OF THE D-ASTERISK(+/-) CROSS-SECTION IN 2-PHOTON COLLISIONS AT LEP
SELVAGGI, Giovanna;NUZZO, Salvatore Vitale;DE PALMA, Mauro
1995-01-01
Abstract
The inclusive production of D*(+/-) mesons in photon-photon collisions has been measured by the Aleph experiment at LEP with a beam energy of 45 GeV. The D*(+) are detected in their decay to D-0 pi(+) with the D-0 observed in three separate decay modes: (1) K(-)pi(+), (2) K(-)pi(+)pi(0) and (3) K(-)pi(+)pi(-)pi(+), and analagously for the D*(-) modes. A total of 33 events was observed from an integrated luminosity of 73 pb(-1) which corresponds to a cross section for sigma(e(+)e(-) --> e(+)e(-)D*(+/-)X) of 155+/-33+/-21 pb, This result is compatible with both the direct production gamma gamma --> in the Born approximation and with a more complete calculation which includes both radiative QCD corrections and contributions in which one of the photons is first resolved into its quark and gluon constituents. The shapes of distributions for events containing a D*(+) are found to be better described by the latter.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
