Abstract
We report a meson exchange model of pion-nucleon interaction, which has recently been developed by our group. Apart from direct and exchange nucleon and delta pole diagrams the Born term of this model includes potentials for the correlated exchange of two pions in the 0{sup +} (`{sigma}`) and 1{sup -} ({rho}) channels. These 2{pi}-exchange potentials are calculated from partial wave amplitudes for the reaction N anti N {yields} {pi}{pi} using the technique of dispersion integrals. Our 2{pi}-exchange potentials are compared with potentials derived from the exchange of `{sigma}`- and {rho}-mesons in conventional meson exchange models, in which the mass distribution of the exchanged 2{pi}-system is neglected. By an investigation of the characteristic differences of these potentials we show that the realistic treatment of correlated 2{pi}-exchange is of crucial importance for the quantitative description of {pi}N scattering data obtained in our model. The rise of the P{sub 11} phase shift is reproduced without an explicit pole term involving the N{sup *}. The description of this partial wave is based on the cancellation between the strong attraction from correlated 2{pi}-exchange and a repulsive contribution from the nucleon pole term. (orig.) [Deutsch] Wir stellen unser Mesonaustauschmodell fuer die {pi}N-Wechselwirkung vor. Neben Pol- und
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Citation Formats
Schuetz, C.
The elastic pion-nucleon interaction in the meson exchange picture; Die elastische Pion-Nukleon-Wechselwirkung im Mesonaustauschbild.
Germany: N. p.,
1993.
Web.
Schuetz, C.
The elastic pion-nucleon interaction in the meson exchange picture; Die elastische Pion-Nukleon-Wechselwirkung im Mesonaustauschbild.
Germany.
Schuetz, C.
1993.
"The elastic pion-nucleon interaction in the meson exchange picture; Die elastische Pion-Nukleon-Wechselwirkung im Mesonaustauschbild."
Germany.
@misc{etde_10119806,
title = {The elastic pion-nucleon interaction in the meson exchange picture; Die elastische Pion-Nukleon-Wechselwirkung im Mesonaustauschbild}
author = {Schuetz, C}
abstractNote = {We report a meson exchange model of pion-nucleon interaction, which has recently been developed by our group. Apart from direct and exchange nucleon and delta pole diagrams the Born term of this model includes potentials for the correlated exchange of two pions in the 0{sup +} (`{sigma}`) and 1{sup -} ({rho}) channels. These 2{pi}-exchange potentials are calculated from partial wave amplitudes for the reaction N anti N {yields} {pi}{pi} using the technique of dispersion integrals. Our 2{pi}-exchange potentials are compared with potentials derived from the exchange of `{sigma}`- and {rho}-mesons in conventional meson exchange models, in which the mass distribution of the exchanged 2{pi}-system is neglected. By an investigation of the characteristic differences of these potentials we show that the realistic treatment of correlated 2{pi}-exchange is of crucial importance for the quantitative description of {pi}N scattering data obtained in our model. The rise of the P{sub 11} phase shift is reproduced without an explicit pole term involving the N{sup *}. The description of this partial wave is based on the cancellation between the strong attraction from correlated 2{pi}-exchange and a repulsive contribution from the nucleon pole term. (orig.) [Deutsch] Wir stellen unser Mesonaustauschmodell fuer die {pi}N-Wechselwirkung vor. Neben Pol- und Austauschdiagrammen fuer das Nukleon und das Delta-Isobar enthaelt der Born-Term dieses Modells Potentiale fuer den korrelierten Austausch zweier Pionen im 0{sup +} (`{sigma}`)- und 1{sup -} ({rho})-Kanal. Diese 2{pi}-Austausch-Potentiale werden ueber Dispersionsintegrale aus Partialwellenamplituden fuer die Reaktion N anti N {yields} {pi}{pi} berechnet. Unsere 2{pi}-Austausch-Potentiale werden mit den Potentialen fuer `{sigma}`- und {rho}-Austausch in konventionellen Mesonaustauschmodellen verglichen, in denen die Massenverteilung des ausgetauschten 2{pi}-Systems vernachlaessigt wird. Anhand der charakteristischen Unterschiede dieser Potentiale zeigen wir, dass die realistische Beschreibung des korrelierten 2{pi}-Austauschs Voraussetzung fuer die quantitative Beschreibung der {pi}N-Streudaten ist, die wir in unserem Modell erhalten. Der Anstieg der P{sub 11}-Phase wird ohen einen Pol-Beitrag eines N{sup *}-Teilchens reproduziert. Die Beschreibung dieser Partialwelle basiert auf der teilweisen Aufhebung der starken Attraktion, die durch den korrelierten 2{pi}-Austausch hervorgerufen wird, und der Repulsion durch den Nukleon-Pol. (orig.)}
place = {Germany}
year = {1993}
month = {Feb}
}
title = {The elastic pion-nucleon interaction in the meson exchange picture; Die elastische Pion-Nukleon-Wechselwirkung im Mesonaustauschbild}
author = {Schuetz, C}
abstractNote = {We report a meson exchange model of pion-nucleon interaction, which has recently been developed by our group. Apart from direct and exchange nucleon and delta pole diagrams the Born term of this model includes potentials for the correlated exchange of two pions in the 0{sup +} (`{sigma}`) and 1{sup -} ({rho}) channels. These 2{pi}-exchange potentials are calculated from partial wave amplitudes for the reaction N anti N {yields} {pi}{pi} using the technique of dispersion integrals. Our 2{pi}-exchange potentials are compared with potentials derived from the exchange of `{sigma}`- and {rho}-mesons in conventional meson exchange models, in which the mass distribution of the exchanged 2{pi}-system is neglected. By an investigation of the characteristic differences of these potentials we show that the realistic treatment of correlated 2{pi}-exchange is of crucial importance for the quantitative description of {pi}N scattering data obtained in our model. The rise of the P{sub 11} phase shift is reproduced without an explicit pole term involving the N{sup *}. The description of this partial wave is based on the cancellation between the strong attraction from correlated 2{pi}-exchange and a repulsive contribution from the nucleon pole term. (orig.) [Deutsch] Wir stellen unser Mesonaustauschmodell fuer die {pi}N-Wechselwirkung vor. Neben Pol- und Austauschdiagrammen fuer das Nukleon und das Delta-Isobar enthaelt der Born-Term dieses Modells Potentiale fuer den korrelierten Austausch zweier Pionen im 0{sup +} (`{sigma}`)- und 1{sup -} ({rho})-Kanal. Diese 2{pi}-Austausch-Potentiale werden ueber Dispersionsintegrale aus Partialwellenamplituden fuer die Reaktion N anti N {yields} {pi}{pi} berechnet. Unsere 2{pi}-Austausch-Potentiale werden mit den Potentialen fuer `{sigma}`- und {rho}-Austausch in konventionellen Mesonaustauschmodellen verglichen, in denen die Massenverteilung des ausgetauschten 2{pi}-Systems vernachlaessigt wird. Anhand der charakteristischen Unterschiede dieser Potentiale zeigen wir, dass die realistische Beschreibung des korrelierten 2{pi}-Austauschs Voraussetzung fuer die quantitative Beschreibung der {pi}N-Streudaten ist, die wir in unserem Modell erhalten. Der Anstieg der P{sub 11}-Phase wird ohen einen Pol-Beitrag eines N{sup *}-Teilchens reproduziert. Die Beschreibung dieser Partialwelle basiert auf der teilweisen Aufhebung der starken Attraktion, die durch den korrelierten 2{pi}-Austausch hervorgerufen wird, und der Repulsion durch den Nukleon-Pol. (orig.)}
place = {Germany}
year = {1993}
month = {Feb}
}