Using HRTS Data in TRANSP

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• Using HRTS Data in TRANSP
• I. Jenkins

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HRTS Data in TRANSP I

• HRTS data now routinely available giving much
  higher resolution esp. at plasma edge.
• However, trajectory of the laser is further from
  the plasma midplane data needs remapping before
  use in TRANSP (this was not an issue for LIDAR)
• Initial attempt used an EFIT equilib. (one time
  point) and used FLUSH routines to remap R vector
  of HRTS. OK for pulses where equilib. Relatively
  stable during period of interest, but still not
  using correct equilib. (FLUSH does not work with
  TRANSP equilib.)

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HRTS data in TRANSP II

• Remapping onto TRANSP equilibrium requires
  initial run with un-mapped data
• This eq. is stored in the .cdf file as a series
  of flux contours (normalised poloidal flux) which
  can be reconstructed
• Then create a 2D (R,z) grid of flux using IDL
  function
• The (R,z) vector of HRTS data can then be
  interpolated onto this grid at each time point
• Then re-interpolate onto fine grid which is
  constant with time
• Write new PPF of re-mapped data

Z (cm)
76063T33 _at_44.718s
R (cm)
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HRTS data in TRANSP III

• Difference in input data to leads to different
  kinetic profiles in TRANSP run
• Here T04 (raw data) compared with T42 (fully
  re-mapped and smoothed)

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HRTS in TRANSP IIII

• Comparison of measured Wdia vs TRANSP calculation

After re-mapping
Before re-mapping (T04)
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Effect on BS Current

• Re-mapping data will have effect on position and
  magnitude of Te,Ne gradients effect on
  calculated bootstrap current

Te,Ne and CURBS _at_6.0s fot 78085 T02 (raw HRTS)
and T11 (remapped) show the difference in
calculated CURBS (bootstrap profile) When
this is integrated can lead to substantial
difference in total BS current
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Conclusions

• Re-mapping HRTS data required for TRANSP
• IDL code developed to do this using equilibrium
  from initial TRANSP run
• Results show improved agreement with measured
  Wdia and better match of kinetic/magnetic plasma
  edge
• Code is available to JET TRANSP runners as
  required
• Ti re-mapping does not cause such big difference
  (not usually strong gradient at edge) but
  re-mapping methods are being investigated