---
format: markdown
title: 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**