ISSN:0094-243X    

DOI:10.1063/1.30841

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

The experimental situation on pion absorption and production, as established by recent (&pgr;,&pgr;N), (&pgr;,NN), (&pgr;, chargedX), (&pgr;,N) and (N,&pgr;) reaction experiments, is reviewed.

ISSN:0094-243X    

DOI:10.1063/1.30842

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

This paper reviews recent calculations of (&pgr;+,p) and (p,&pgr;+) reaction cross sections leading to low‐lying states of light nuclei. The experimental evidence for or against various models is discussed, and it is concluded that the bulk of the differential cross section may be described as ’’pionic stripping.’’ The outlook for nuclear spectroscopy at large momentum transfer, by means of these reactions, is reviewed.

ISSN:0094-243X    

DOI:10.1063/1.30844

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

New measurements of pion‐nucleus total cross sections have been made at LAMPF and BNL. The results from LAMPF include measurement of the difference of the rms neutron and proton radii of48Ca to be 0.08±0.02 and that of180 to be 0.19±0.02. The BNL measurements provide a new phenomenology on the downshift and spreading of the (3–3) resonance in nuclei from the first data on heavy nuclei. A new technique for handling the Coulomb effects in total cross‐section measurements is discussed.

ISSN:0094-243X    

DOI:10.1063/1.30845

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

We consider some aspects of the problem of the interaction of a probe with a nucleus in the energy region where the elementary probe‐nucleon interaction resonates. The case of pion‐nucleus scattering is treated as an illustration.

ISSN:0094-243X    

DOI:10.1063/1.30846

出版商:AIP    

年代:1976

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.30848

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Angular distribution of16(O(&pgr;+,p)15O have been obtained for the two hole states of15O: the (p3/2)−1state at 6.18 MeV and the (p1/2)−1ground state. The ratio of the two differential cross‐sections is larger than 8 at all angles. A comparison is made with preliminary calculations of G.A. Miller. A measurement has also been performed at two angles on the reaction16(&pgr;−,p)15C.

ISSN:0094-243X    

DOI:10.1063/1.30849

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Using TRIUMF proton beams of 400–500 MeV bombarding carbon and copper targets we have measured positive pion production cross sections for pion energies 20 to 100 MeV and pion angles 60 to 150°. The pions were stopped in a range telescope in which time‐of‐flight, energy loss, and the detection of the pion decay were used for particle identification.

ISSN:0094-243X    

DOI:10.1063/1.30850

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

Different models for (p,&pgr;) production are discussed.

ISSN:0094-243X    

DOI:10.1063/1.30851

出版商:AIP    

年代:1976

数据来源: AIP

摘要:

The covariant neutron‐exchange mechanism is formulated for12C(p,&pgr;+)13Cg.s. using relativistic wave functions obtained from nuclear models based on the Dirac equation for the (A+1) system. Ambiguities associated with the nonrelativistic reduction of the (&pgr;NN) vertex are eliminated. It is found that the (p,&pgr;+) results are surprisingly sensitive to the choice of pseudoscalar or axial‐vector (&pgr;NN) coupling.

ISSN:0094-243X    

DOI:10.1063/1.30852

出版商:AIP    

年代:1976

数据来源: AIP