Target effects on the linear polarization of REC radiation from U91+ ions

نویسندگان

  • A. N. Artemyev
  • A. Surzhykov
  • S. Fritzsche
  • B. Najjari
  • A. B. Voitkiv
چکیده

In the last decades, the photon emission from highly charged ions has been found a versatile tool for exploring light-matter interactions in strong (Coulomb) fields [1]. Apart from a series of energy and angle resolved experiments, especially for the x-ray emission following the radiative electron capture (REC) into high-Z projectile ions [2], recent emphasis was placed on measuring the linear polarization of this radiation [3], by making use of recent advances in detector technology [4]. However, while most REC calculations for high-Z projectiles are based so far on first-order perturbation theory in the electron-photon interaction, a rigorous analysis of this capture process would require, in general, a timedependent, two-center Dirac description. Of course, such an extensive description is well beyond of what is presently feasible, but it appears at least necessary for angle-resolved and polarization measurements to take into account the structure of the target atoms. This will be true especially if impact-parameter dependent measurements are to be performed in forthcoming years. Therefore, in order to improve our understanding of the target effects upon the REC (linear) polarization from high-Z ions, we applied the impulse approximation as appropriate for fast collisions of heavy projectiles with lowand medium-Z targets [5]. Within the impulse approximation, the collision of the projectile with the target atom is still described in perturbation theory but asymmetrically by introducing an explicit momentum distribution for the target electrons. In this approximation, therefore, the initial state of the captured electron is expressed as

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Alignment of heavy, few-electron ions following Coulomb excitation in collisions with light targets

In relativistic ion-atom and ion-electron collisions, different processes are known that lead to the formation of excited or ionized states of the projectile ions. In their subsequent de-excitation, the ions then often emit one (or several) x-ray photons until the ionic ground state is reached. From the analysis of this ‘characteristic’ radiation, important information can be obtained about the...

متن کامل

Linear polarization and angular distribution of Lyman-α1 radiation following from the REC process in collisions of bare uranium ions with H2

G. Weber1,2, H. Bräuning1, S. Hess1,3, U. Spillmann1,3, S. Fritzsche2, S. Geyer1,3, R. Märtin1,3, R. Reuschl1,3, A. Surzhykov2, S. Trotsenko1,3, D. Winters1, and Th. Stöhlker1,2 1GSI, Darmstadt, Germany; 2University of Heidelberg, Germany; 3University of Frankfurt, Germany For high-Z systems the elementary process of photoionization is studied best in inverse kinematics by utilizing its time-re...

متن کامل

Kα1 decay of helium–like uranium ions following radiative electron capture

Studies of the charge transfer in relativistic ion–atom collisions have a long tradition at the GSI storage ring [1]. In the radiative electron capture (REC), for example, a free (or quasi–free) electron is captured into a bound state of the projectile ion, accompanied by the simultaneous emission of a recombination photon. The angular and polarization properties of such photons have been explo...

متن کامل

Angular distribution and linear polarization of Bremsstrahlung arising from ion-atom collisions

Bremsstrahlung is one of the basic photon-matter processes occuring in collisions of electrons with atoms and ions. Ion-atom collisions in ion storage rings provide an unique tool to study this process under single-collision conditions in the domain of strong, unpertubated Coulomb fields, such as it prevails in few-electron, high-Z projectiles. Of special interest is the high energy limit of th...

متن کامل

Track detection on the cells exposed to high LET heavy-ions by CR-39 plastic and terminal deoxynucleotidyl transferase (TdT)

Background: The fatal effect of ionizing radiation on cells depends on Linear Energy Transfer (LET) level. The distribution of ionizing radiation is sparse and homogeneous for low LET radiations such as X or γ, but it is dense and concentrated for high LET radiation such as heavy-ions radiation. Material and Methods: Chinese hamster ovary cells (CHO-K1) were exposed to 4 Gy Fe-ion 2000 keV/...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2011