BEGIN:VCALENDAR
VERSION:2.0
PRODID:icalendar-ruby
CALSCALE:GREGORIAN
X-WR-CALNAME:Remote Broadcast: Shaun Haskey
X-WR-TIMEZONE:Eastern Time (US & Canada)
BEGIN:VEVENT
DTSTAMP:20260813T180550Z
UID:tag:localist.com\,2008:EventInstance_32802394719202
DTSTART:20200313T190000Z
DTEND:20200313T200000Z
DESCRIPTION:PSFC Seminar: Active spectroscopy measurements of the Deuterium
  temperature\, rotation\, and density in the pedestal region of the DIII-D
  tokamak\,\na seminar by Shaun Haskey\, \nBroadcast from Princeton Plasma 
 Physics Laboratory\n\nMain-ion charge exchange recombination spectroscopy 
 (MICER) [1\,2] uses the neutral beam induced D-alpha emission spectrum to 
 determine the local deuterium ion (D+) temperature\, rotation and density\
 , as well as several beam and equilibrium properties from the neutral beam
  emission. An edge MICER system consisting of 16 densely packed sightlines
  was installed on DIII-D extending the MICER technique from the core to th
 e pedestal and steep gradient region of H-mode plasmas where the D+ and co
 mmonly measured impurity ion properties can differ significantly. A combin
 ation of iterative collisional radiative modeling techniques and greatly a
 ccelerated spectral fitting algorithms allowed the extension of this diagn
 ostic technique to the plasma edge where the steep gradients introduce sig
 nificant diagnostic challenges that require employing direct synthetic dia
 gnostic modeling. Data from a wide range of plasma conditions has been acq
 uired uncovering sometimes large temperature differences between D+ and im
 purity ions near the separatrix\, inwardly shifted C6+ density pedestals\,
  and rapid co-Ip D+ edge rotation. These observations provide significantl
 y better experimental data for testing models and improving understanding 
 in areas such as ion thermal transport and intrinsic rotation. For example
  the D+ temperature measurements resolve inconsistencies such as negative 
 ion heat fluxes near the plasma edge\, which are sometimes inferred when u
 sing the historical assumption that the impurity ion temperature is a good
  proxy for the D+ temperature. The measurements and analysis demonstrate t
 he state of the art in active spectroscopy and integrated modeling for dia
 gnosing fusion plasmas and the importance\, despite the difficulties\, of 
 direct D+ measurements at the plasma edge.\n[1] B.A Grierson\, RSI\, 2012\
 n[2] S.R Haskey\, RSI\, 2018
GEO:42.359858;-71.099164
LOCATION:Building NW17\, 218
SUMMARY:Remote Broadcast: Shaun Haskey
URL;VALUE=URI:https://calendar.mit.edu/event/psfc_seminar_shaun_haskey
CATEGORIES:Meetings/Gatherings
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END:VCALENDAR