Browsing by Author "Kozhuharov, C."

Article

Experiments on e+e--line emission in HI collisions

Bär, R.; Bałanda, A.; Baumann, J.; Berg, W.; Bethge, K.; Bokemeyer, H.; Folger, H.; Fröhlich, O.; Ganz, R.; Hartung, O.; Samek, M.; Salabura, P.; Schön, W.; Schwalm, D.; Stiebing, K.; Thee, P.; Berdermann, E.; Heine, F.; Heinz, S.; Joeres, O.; Kienle, P.; Koenig, I.; Koenig, W.; Kozhuharov, C.; Leinberger, U.; Schröter, A.; Tsertos, Haralambos (1995)

Article

First energy and angle differential measurements of e+e--pairs emitted by internal pair conversion of excited heavy nuclei

Leinberger, U.; Berdermann, E.; Heine, F.; Heinz, S.; Joeres, O.; Kienle, P.; Koenig, I.; Koenig, W.; Kozhuharov, C.; Schröter, A.; Tsertos, Haralambos; Hofmann, C.; Soff, G. (1998)

We present the first energy and angle resolved measurements of e+e--pairs emitted from heavy nuclei (Ζ ≥ 40) at rest by internal pair conversion (IPC) of transitions with energies of less than 2 MeV as well as recent ...

Article

High-sensitivity measurements of the excitation function for Bhabha scattering at MeV energies

Tsertos, Haralambos; Kozhuharov, C.; Armbruster, P.; Kienle, P.; Krusche, B.; Schreckenbach, K. (1989)

Using a monochromatic e+ beam scattered on a Be foil and a high-resolution detector device, the excitation function for elastic e+e- scattering was measured with a statistical accuracy of 0.25% in 1.4-keV steps in the ...

Article

Investigations of correlated ρ+ e- emission in heavy-ion collisions near the Coulomb barrier

Koenig, I.; Berdermann, E.; Bosch, F.; Kienle, P.; Koenig, W.; Kozhuharov, C.; Schröter, A.; Tsertos, Haralambos (1993)

We present the results obtained from a series of ρ+ρ--coincidence measurements in heavy-ion collisions using the double-Orange β-spectrometer at GSI. The collision systems U+U, U+Pb, and U+Ta were investigated at bombarding ...

Article

Monoenergetic (e+e-) pairs from heavy ion collisions

Berdemann, E.; Bosch, F.; Kienle, P.; Koenig, W.; Kozhuharov, C.; Tsertos, Haralambos; Schuhbeck, S.; Huchler, S.; Kemmer, J.; Schröter, A. (1988)

Energy and angular correlations of (e+e-) pairs emitted in HI collisions were investigated. Some evidence is found for a weak peak at 815±5keV in the (e+e-) sum-energy spectrum obtained for θe+c- = 180° ± 18° (FWHM). The ...

Article

Multiple positron structures observed from U-U collisions at 5.6 MeV/u and 5.9 MeV/u

Tsertos, Haralambos; Bosch, F.; Kienle, P.; Koenig, W.; Kozhuharov, C.; Berdermann, E.; Huchler, S.; Wagner, W. (1987)

High resolution positron spectroscopy in U-U collisions at bombarding energies of 5.6 MeV/u, the lowest energy studied until now as well as of 5.9 MeV/u, reveals similar multiple structures between 220 keV and 385 keV ...

Article

Narrow positron lines from U-U and U-Th collisions

Clemente, M.; Berdermann, E.; Kienle, P.; Tsertos, Haralambos; Wagner, W.; Kozhuharov, C.; Bosch, F.; Koenig, W. (1984)

Spectra of positrons emitted in heavy-ion-atom collisions close to the Coulomb barrier were measured. The data exhibit broad energy distributions according to expectations for induced positron creation by the strong ...

Article

New limits for resonant Bhabha scattering around the invariant mass of 1.8 MeV/c2

Tsertos, Haralambos; Kozhuharov, C.; Armbruster, P.; Kienle, P.; Krusche, B.; Schreckenbach, K. (1988)

The excitation function for Bhabha scattering was reinvestigated in the energy range between 775 and 840 keV (c.m.) in 1.4 keV steps using a monoenergetic e+ -beam and a high-resolution kinematic coincidence detector device. ...

Article

New results on e+e--line emission in U+Ta collisions ORANGE collaboration at GSI

Leinberger, U.; Berdermann, E.; Heine, F.; Heinz, S.; Joeres, O.; Kienle, P.; Koenig, I.; Koenig, W.; Kozhuharov, C.; Rhein, M.; Schröter, A.; Tsertos, Haralambos (1997)

We present new results obtained from a series of follow-up e+e--coincidence measurements in heavy-ion collisions, utilizing an improved experimental set-up at the double-Orange β-spectrometer of GSI. The collision system ...

Article

On the momentum correlation of (e+e-) pairs observed in U + U and U + Pb collisions

Koenig, W.; Berdermann, E.; Bosch, F.; Huchler, S.; Kienle, P.; Kozhuharov, C.; Schröter, A.; Schuhbeck, S.; Tsertos, Haralambos (1989)

First results on the energy and angular dependence of the (e+e-) pairs, emitted from U + U and U + Pb collisions at a beam energy of 5.9 MeV/u, are presented. The (e+e-) coincidence measurements were carried out utilizing ...

Article

On the production mechanism of the narrow positron lines observed in heavy-ion collisions

Tsertos, Haralambos; Bosch, F.; Kienle, P.; Koenig, W.; Kozhuharov, C.; Berdermann, E.; Clemente, M.; Wagner, W. (1987)

Following a suggestion of Bang et al. we deduce that the total energy transfer associated with the narrow positron lines observed in heavy-ion collisions is given approximately by the sum of the rest masses of the positron ...

Article

On the scattering-angle dependence of the monochromatic positron emission from U + U and U + Th collisions

Tsertos, Haralambos; Berdermann, E.; Bosch, F.; Clemente, M.; Kienle, P.; Koenig, W.; Kozhuharov, C.; Wagner, W. (1985)

The narrow positron lines emitted in U + Th and U + U collisions were investigated with respect to their dependence on the heavy-ion scattering angle Θp. For U + U collisions also the excitation function was measured which ...

Article

Positron lines from subcritical heavy ion-atom collisions

Koenig, W.; Bosch, F.; Kienle, P.; Kozhuharov, C.; Tsertos, Haralambos; Berdermann, E.; Huchler, S.; Wagner, W. (1987)

Positron lines were observed in heavy ion-atom collisions at bombarding energies close to the Coulomb barrier in subcritical systems with the sum of the atomic numbers of the colliding nuclei Zu=Z1+Z2 being smaller than ...

Article

Positron spectra from internal pair conversion observed in 238U + 181Ta collisions

Heinz, S.; Berdermann, E.; Heine, F.; Joeres, O.; Kienle, P.; Koenig, I.; Koenig, W.; Kozhuharov, C.; Leinberger, U.; Rhein, M.; Schröter, A.; Tsertos, Haralambos (2000)

We present new results from measurements and simulations of positron spectra, originating from 238U + 181Ta collisions at beam energies close to the Coulomb barrier. The measurements were performed using an improved ...

Article

Sensitive search for neutral resonances in Bhabha scattering around 1.8 MeV/c2

Tsertos, Haralambos; Kozhuharov, C.; Armbruster, P.; Kienle, P.; Krusche, B.; Schreckenbach, K. (1988)

The excitation function for Bhabha scattering was measured in the energy range between 760 and 840 keV (CM) in 1.4 keV steps with beams of monochromatic positrons scattered on a Be foil at angles between 79° and 101° (CM). ...

Article

Systematic studies of positron production in heavy-ion collisions near the Coulomb barrier

Tsertos, Haralambos; Berdermann, E.; Bosch, F.; Clemente, M.; Huchler, S.; Kienle, P.; Koenig, W.; Kozhuharov, C. (1992)

We present the results obtained from systematic studies of positron creation for a series of heavy-collision systems, with united charge Zu=Z1+Z2 ranging from Zu=164 (Pb + Pb) to Zu=184 (U+U) at bombarding energies close ...

Article

Weak e+e- lines from internal pair conversion observed in collisions of 238U with heavy nuclei

Heinz, S.; Berdermann, E.; Heine, F.; Joeres, O.; Kienle, P.; Koenig, I.; Koenig, W.; Kozhuharov, C.; Leinberger, U.; Rhein, M.; Schröter, A.; Tsertos, Haralambos (1998)

We present the results of a Doppler-shift correction to the measured e+e--sum-energy spectra obtained from e+e--coincidence measurements in 238U + 206Pb and 238U + 181Ta collisions at beam energies close to the Coulomb ...