Future Projects

Development of COLTRIMS-DOTAREEA setup:

We would like to augment and strengthen our present experimental techniques (recoil-ion, e-spectroscopy) by introducing a coincidence detection of all particles in the final state, namely, the secondary electrons, the recoil-ions and the scattered projectile-ions to perform kinematically complete experiments. In order to achieve this goal, a setup consisting a COLTRIMS (to measure the momentum of the recoil-ions), along with a DOuble-Toroidal Angle Resolved Electron Energy Analyzer (DOTAREEA for simultaneous measurement of energy and angular distributions of secondary electrons) and a charge state analyzer (to measure the final state charge of the projectile-ions) will be built.

  1. We plan to extend the studies on two-center mechanism of electron emission in fast and intermediate velocity ion-collisions with simple atoms/molecules: He, H, H2. Ionization as well as electron capture from diatomic molecules e.g. N2 and O2 could be used to investigate more about the coherence-driven Cohen-Fano oscillations in Young type interference effect in these inversion symmetric, homo-nuclear, diatomic molecules. These experiments will complement the recent advancements in the photo-ionization studies on these systems which has implications on fundamental aspects of the quantum-entanglement problem. A COLTRIMS-DOTAREEA setup would be ideal to study these fundamental aspects of the atomic collision processes in a kinematically complete fashion.
  2. The single and multiple electron transfer are dominant processes in slow collisions with HCIs. The electron transfer in slow collisions from a ground state atom to the highly excited states of a multiply charged projectile ion is complex to describe theoretically, owing to the highly non-perturbative nature of the collisions. The ECR beam energy range corresponds to the intermediate/low velocity for electron capture from noble gas targets and therefore maximizing the electron capture probability. A state selective measurement of electron transfer cross sections in collisions with atoms molecules using a COLTRIMS-DOTAREEA is planned.
    • We plan to initiate measurement of total e-capture from Ar and other noble gas cluster targets.
    • On the other hand there is a possible scope (in collaboration) to extend it to the measurement of electron capture from a suitably chosen laser excited Rydberg state.
    • The noble gas cluster source can also be used to investigate the recently proposed Inter-atomic Coulomic Decay (ICD) process in such clusters.

Collisions with large (bio-) molecules/PAHs/clusters:

The cooperative motion of electrons leading to a giant resonance plays also an important role in heavy ions collisions with large atoms, clusters, fullerenes and even in certain bio-molecules. We have recently used electron capture, ionization and fragmentation processes in a C60 fullerene target to demonstrate the effect of such collective plasmon excitation on the recoil-ion and electron emission. These measurements will now be extended. Besides carbon clusters, Polycyclic Aromatic Hydrocarbon (PAH) molecules are of current research interest due to their importance in the environmental science, nano-electronics and astrophysics. The infrared absorption spectrum indicates the existence of PAHs in interstellar medium or solar atmosphere in which keV energy ion collisions are quite common. Understanding the interactions of the highly charged ions with these molecules is of importance for various applications.Physics of ion-atom collision deals with the fundamental three-body scattering problem and can be easily applied to interdisciplinary areas, such as, molecules, clusters, large bio-molecules, nano-solvated bio-molecular ions in gas phase, clusters of bio-molecules, solids, surfaces and nanotubes. The basic collision processes, such as ionization, excitation, electron transfer and the coupling among these channels, play an important role to understand the collision dynamics involved. The ECR-on 400 kV high voltage deck provides an ideal platform to investigate collision processes at intermediate velocity range.

Development of Internally cold (Bio-) molecular ion beam facility:

It is important to understand the dynamics of various interactions of bio-molecules when they are surrounded by an environment, namely, solvent molecules such as water, alcohol, or other smaller bio molecules and also clusters of bio-molecules etc. To this end, a bio-molecular ion beam facility which can deliver very low-energy, internally cold ions (molecular ions residing in states very close to their rotational ground states) could be used to perform crossed beam experiments with highly charged ions from ECRIA. A unique combination of an Electro Spray Ionization source (ESI), an RF Ring Electrode Trap (RET) with temperature control (buffer gas cooling), and an ECRIA is proposed to be built in order to study heavy-ion induced fragmentation (radiation damage) and also collision induced dissociation (CID) of complex bio-molecular ions, often, in the presence of an environment. The capability of controlling the initial quantum states of these ions helps to access to new and more precise information concerning the fundamental atomic and molecular interaction processes. Bio-molecules such as proteins, RNA and DNA etc. not only have important functions in our cells, but they are also being engineered for a variety of applications in biotechnology. It is therefore desirable to find means to modify the molecular structure of peptides and DNA molecules in a predictable and controlled way. Fragmentation is of interest because of its potential application to protein sequencing. The presently proposed source is a versatile one, which can practically deliver any kind of bio-molecular ions (including large proteins, peptides and the constituents of DNA/RNA etc). Further, the possibility of performing experiments with single, internally cold, bio-molecular ions and also to study reactions with interstellar molecular ions (such as PAHs) would be highly desirable.