Pb shielding of NaITl detector - first attempt (2. 4. 2019)

#Aim of experiment

  • first test of shielding of scintillation detector to reduce flux of HXR radiation
  • attempt to build a proper shielding in order to be possible reduce a flux of radiation and detect single photons and not burst of radiation
  • reduction of flux of radiation approaching a detector is needed to make a proper spectra of HXR radiation, which is produced by RE in GOLEM tokamak

#Short description

  • present: J. Čeřovský, A. Kolínská, O. Ficker, V, Svoboda
  • led bricks were borrow from COMPASS
  • several shielding “bunkers” were build and influence on detection of HXR radiation was observed
  • standard NaITl scintillation detector was used

#Experimental setting

  • standard plasma diagnostics
  • RE related diagnostics: NaITl (\(U_{PS} = 550 \ \mathrm{V}\))

#Logbook

Shot \(U_{CD} \ [\mathrm{V}]\) \(U_{BT} \ [\mathrm{V}]\) \(t_{d} \ [\mathrm{ms}]\) \(p_{wg} \ \mathrm{mPa}\) \(t_{p} \ \mathrm{ms}\) Type of shielding Note
30187 500 1000 0 13 12.0 above bunker (bunker on the ground) no HXR signal
30188 500 1000 0 13 13.4 above bunker (bunker on the ground) no HXR signal - data aquissition cable connected to trigger not to osciloscope
30189 500 1000 0 13 14.5 above bunker (bunker above ground) HXR signal
30190 500 1000 0 13 13.1 in bunker (bunker above ground) no HXR signal
30191 500 1000 0 13 13.2 - no HXR signal
30192 500 1000 0 13 13.0 above bunker (bunker on the ground) some HXR signal
30193 500 1000 0 13 13.8 need to be add! need to be add!
30194 450 1000 0 13 12.9 need to be add! need to be add!
30195 450 1300 0 13 14.7 need to ne add! need to be add!
30196 450 1300 0 13 15 need to be add! need to be add!
30197 450 1300 0 13 14.7 only led cylinder (on the ground) some HXR peaks - not many
30198 450 1300 0 13 15.5 bottom part of led cylinder only (on the ground still) much more peaks than in previous configuration as expected
30199 450 1300 0 13 15.5 only led cylinder, but placed on the table higher signal then on the ground
30200 450 1300 0 13 15.9 led cylinder + one line of led bricks from sides and front flux of radiation reduces
30201 450 1300 0 13 16.1 led cylinder + one line of led bricks from sides and front with small gap greater flux of radiation then previous (as expected)
30202 450 1300 0 13 15 previous but without gap almost negligible HXR signal
30203 450 1300 0 13 15.9 gap 4.1 mm
30204 450 1300 0 13 15.6 gap 4.1 mm
30205 450 1300 0 13 19.3 gap 7.5 mm
30206 450 1300 0 13 15.9 gap 7.5 mm + bricks placed more closely to each other + additional small brick above gap
30207 450 1300 0 13 19.5 same as previous
30208 450 1300 0 13 19.8 same as previous
30209 450 1300 0 13 19.6 gap 1.7 cm
30210 450 1300 0 13 18.9 same as previous
30211 450 1300 0 13 20.5 same as previous best shot of the day
30212 450 1300 0 13 19.7 same as previous
30213 450 1300 0 13 19.7 same as previous + brick above gap
30214 450 1300 0 13 20.1 visible whole hole in cylinder
30215 450 1300 0 13 19.3 same as previous
30216 450 1300 0 13 19.1 gap closed
30217 450 1300 0 13 19.2 gap closed
30218 450 1300 0 13 19.0
30219 450 1300 0 13 20.3
30220 450 1300 0 13 20.3
30221 450 1300 0 13 19.0
30222 450 1300 0 13 19.2

#Short analysis