This work embraces the measurement of angular distributions and excitation functionsudfor proton radiative capture to the ground and excited states of 13N, in energy steps fromudE p = 40 to E p = 52MeV.udLegendre polynomial fits to the angular distributions are made and the energy variationudof Legendre coefficients is established for several (p, 7 ) transitions involving statesudup to an excitation energy of 15 MeV. The polynomial coefficients are explained by largeuddipole-quadrupole interference effects, particularly interesting at excitation energies correspondingudto twice (£„ ~ 46 MeV) the centroid value of the ground state based GiantudDipole Excitation. Broad resonances are found in the (p,7o) &nd the (p, 72+3) channels,udwhich involve final states that are members of the same rotational band and thereforeudshould present very similar internal structures as the almost equivalent Legendre coefficientsudsubstantiate. For other excited states similar trends have been found althoughudwithin limits imposed by larger experimental errors.udThe 2hw -+ Ihuj transition is found largely superimposed on inelastic proton scatteringudchannels, contrary to what was established in previous experiments. Upper limits for theudexcitation functions are extracted and only for the highest measured energy point are theudtwo contributions clearly separated.udThis reasearch program is based on a newly-developed anti-coincidence large-volumeudscintillation spectrometer designed by means of a Monte Carlo simulation code. Sp jcificudtests performed with Tandem accelerator beams, and routine application at higher energies,uddemonstrate the excellent correspondence of the design expectations with the performanceudas measured, for this spectrometer.
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