TJ-II: impact of impurities on turbulence
Experimental campaign
Spring 2022
Proposal title
Impact of impurities on turbulent transport
Name and affiliation of proponent
García-Regaña, J. M., Baciero, A., Calvo, I., Carralero D., Estrada T., González-Jerez A., López-Miranda, B., Medina, F., McCarthy K. J., Ochando, M. A., Thienpondt, H., Velasco, J. L., and the TJ-II team, Laboratorio Nacional de Fusion, CIEMAT (Spain)
Details of contact person at LNF
jose.regana@ciemat.es
Description of the activity
Motivation.
In the context of analytical theory, the stabilizing role of impurities on Ion-Temperature-Gradient (ITG) driven instability has been known for decades, see e.g. [1], where the linear dispersion relation shows that the increase of the impurity concentration has a positive impact on the critical gradient of the toroidal ITG mode and its growth rate. Numerically, and on a quasi-linear fashion, in [2] the benign impact of increasing the effective charge, $Z_{\text{eff}}$, on ITG stability, albeit for the simplified geometry slab.
Proposal
In the present proposal the impact of impurities on the background turbulence will be studied.
International or National funding project or entity
Include funding here (grants, national plans)
Description of required resources
Required resources:
- Number of plasma discharges or days of operation:
- Essential diagnostic systems:
- Type of plasmas (heating configuration):
- Specific requirements on wall conditioning if any:
- External users: need a local computer account for data access: yes/no
- Any external equipment to be integrated? Provide description and integration needs:
Preferred dates and degree of flexibility
Preferred dates: (format dd-mm-yyyy)