Eur. Phys. J. D (2012) 66: 303
https://doi.org/10.1140/epjd/e2012-30330-y

Regular Article

Ionization of uracil in collisions with fast bare ions

¹ Tata Institute of Fundamental Research, Colaba, 400005 Mumbai, India
² Laboratorio de Colisiones Atómicas, Instituto de Física Rosario, Universidad Nacional de Rosario and CONICET, Av. Pellegrini 250, 2000 Rosario, Argentina
³ Laboratoire de Physique Moléculaire et des Collisions, Université Paul Verlaine-Metz, 57012 Metz Cedex 01, France

^a e-mail: lokesh@tifr.res.in

Received: 24 May 2012
Received in final form: 21 September 2012
Published online: 4 December 2012

Abstract

We study the atomic collisions with large molecules and simple atoms. The ionization and fragmentation spectra are investigated for uracil, a RNA base molecule, under the impact of fast bare C, O and F-ions. The experiments are conducted using a recoil-ion time-of-flight spectrometer. The energy dependence of the total ionization cross sections (TCS) and fragmentation yields are measured for MeV/u energies. In addition, the angular distribution of the electron double differential cross sections (DDCS) are also shown in some cases. The total cross sections of ionization and also the DDCS data are compared with the CDW-EIS calculations. The qualitative agreement is good but, in general, the theory tends to overestimate the data by a factor of 2.2. The angular distribution of electrons clearly indicates a good qualitative agreement except for the lowest energy electrons.