Pентгеновские спектры ридберговской серии Ne - подобной меди, нагреваемой нано - и фемтосекундным лазерным излучением
, , K. B. Fournier 1, F. Flora2, S. Bollanti2, P. Di Lazzaro2, D. Murra2, A. Grilli3, A. Reale4, L. Reale4, G. Tomassetti4, A. Ritucci4, I. Bellucci5, S. Martellucci5, G. Petrocelli5, T. Auguste6, S. Hulin6, P. Monot6, P. D'Oliveira6.
Центр данных по спектрам многозарядных ионов ГНЦ ВНИИФТРИ, Менделеево, Московская обл., 141570, Россия,
e-mail: *****@***ru
1Lawrence Livermore National Laboratory, P. O. Box 808, L41, Livermore, CA 94550, USA
2ENEA, Dipartimento Innovazione, Settore Fisica Applicata, 00044 Frascati, Roma, Italy
3INFN Frascati, 00044 Frascati, Rome, Italy
4Dipartimento di Fisica e INFM, INFN g. c. LNGS, Universit‘a dell'Aquila, 67010 L'Aquila, Italy
5INFM Dipartimento di Scienze e Tecnologie Fisiche ed Energetiche, Universit‘a di Roma Tor Vergata, Via di Tor Vergata, 00133 Roma, Italy
6Commissariat ‘a l'Energie Atomique, Centre d'Etudes de Saclay, DRECAM, Service de Photons Atomes et Mol’ecules, Bat. 522, 91191 GifSurYvette, France
Spectra in the 7.50 to 8.70 Å range from highly charged copper ions are compared for three different laser produced plasmas. The spectra are recorded with a spherically bent crystal spectrometer using either a mica or quartz crystal for moderate (l¤dl = 3000) and high (l¤dl= 8000) energy resolution, respectively. The plasmas from which the spectra are emitted are formed with either a Nd:glass (15 ns pulse) or Ti:Sapphire (60 fs pulse) or a XeCl (12 ns pulse) laser. Systematic variations in the observed spectra with pulse energy are studied. Line identifications are made for Na, Ne, F and Olike copper ions based on relativistic atomic structure calculations that account for configuration interaction in level energies and transition rates. Collisionalradiative models are computed for the emission from each plasma; the sensitivity of the model spectra to escape factors and to populations of superthermal electrons is studied. For the Nd:glass laser produced plasmas, escape factors are necessary to get the correct relative intensities of highn (n = 5, 6) Nelike Cu19+ emission features. It is found that the Ti:Sapph 60 fs pulse laser produced plasma has a population of superthermal electrons (Thot = 5 keV) that is 5x10-5 - 10-6 that of the bulk electron population (Tbulk ~ 0.2 keV).
