09-08-2016 - Revision history

Burgjeff: /* Thorium plate rates. */

2016-09-27T20:58:37Z

Thorium plate rates.

Burgjeff: /* Thorium plate rates. */

2016-09-27T20:52:36Z

Thorium plate rates.

Burgjeff: /* Shielding & Beam dump impact on gamma flash */

2016-09-20T22:32:13Z

Shielding & Beam dump impact on gamma flash

Burgjeff at 19:24, 20 September 2016

2016-09-20T19:24:23Z

Show changes

Foretony: /* End of Run summary */

2016-09-12T18:22:29Z

End of Run summary

Foretony: /* End of Run summary */

2016-09-12T18:19:23Z

End of Run summary

Burgjeff at 21:25, 9 September 2016

2016-09-09T21:25:01Z

Burgjeff: /* End of Run summary */

2016-09-08T23:34:54Z

End of Run summary

Burgjeff: /* End of Run summary */

2016-09-08T23:30:52Z

End of Run summary

Burgjeff: /* End of Run summary */

2016-09-08T23:27:46Z

End of Run summary

@@ Line 70: / Line 70: @@
 |5320 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator wide open to 8 mm slit, Cell side collimator OPEN to 7.5 cm , radiator 1.5" IN , Target is '''EMPTY''' , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace  half lead brick with battle ship steel 17" high 24" deep and 4" beam left right [[File:Rate2nC_5320.png|40px]][[File:Run5320_ToF_Histograms.png|40px]]
 |-
-|5321 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator wide open to 8 mm slit, Cell side collimator OPEN to 7.5 cm , radiator 1.5" IN , Target is '''Thorium plate''' orthogonal to beam (90)  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace  half lead brick with battle ship steel 17" high 24" deep and 4" beam left right [[File:Rate2nC_5321.png|40px]][[File:Run5321_ToF_Histograms.png|40px]][[File:TargetInMinusOut(runs5321and5320).png|60px]]
+|5321 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator wide open to 8 mm slit, Cell side collimator OPEN to 7.5 cm , radiator 1.5" IN , Target is '''Thorium plate''' orthogonal to beam (90)  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace  half lead brick with battle ship steel 17" high 24" deep and 4" beam left right [[File:Rate2nC_5321.png|40px]][[File:Run5321_ToF_Histograms.png|40px]] Target in minus target out -> [[File:TargetInMinusOut(runs5321and5320).png|60px]]
 |-
 |5322 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator wide open to 8 mm slit, Cell side collimator OPEN to 7.5 cm , radiator 1.5" IN , Target is '''Empty''' orthogonal to beam (90)  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace  half lead brick with battle ship steel 17" high 24" deep and 4" beam left right [[File:Rate2nC_5322.png|40px]][[File:Run5322_ToF_Histograms.png|40px]]

@@ Line 70: / Line 70: @@
 |5320 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator wide open to 8 mm slit, Cell side collimator OPEN to 7.5 cm , radiator 1.5" IN , Target is '''EMPTY''' , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace  half lead brick with battle ship steel 17" high 24" deep and 4" beam left right [[File:Rate2nC_5320.png|40px]][[File:Run5320_ToF_Histograms.png|40px]]
 |-
-|5321 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator wide open to 8 mm slit, Cell side collimator OPEN to 7.5 cm , radiator 1.5" IN , Target is '''Thorium plate''' orthogonal to beam (90)  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace  half lead brick with battle ship steel 17" high 24" deep and 4" beam left right [[File:Rate2nC_5321.png|40px]][[File:Run5321_ToF_Histograms.png|40px]]
+|5321 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator wide open to 8 mm slit, Cell side collimator OPEN to 7.5 cm , radiator 1.5" IN , Target is '''Thorium plate''' orthogonal to beam (90)  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace  half lead brick with battle ship steel 17" high 24" deep and 4" beam left right [[File:Rate2nC_5321.png|40px]][[File:Run5321_ToF_Histograms.png|40px]][[File:TargetInMinusOut(runs5321and5320).png|60px]]
 |-
 |5322 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator wide open to 8 mm slit, Cell side collimator OPEN to 7.5 cm , radiator 1.5" IN , Target is '''Empty''' orthogonal to beam (90)  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace  half lead brick with battle ship steel 17" high 24" deep and 4" beam left right [[File:Rate2nC_5322.png|40px]][[File:Run5322_ToF_Histograms.png|40px]]
@@ Line 77: / Line 77: @@
 |}
 =End of Run summary=

@@ Line 35: / Line 35: @@
 |5314 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator open to 0.2563 cm, Cell side collimator OPEN to 2 cm , radiator 3/4" IN , Target is EMPTY  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace aluminium dump with a half lead brick '''centered 4" from beam''' center [[File:Rate2nC_5314.png|40px]][[File:Run5314_ToF_Histograms.png|40px]]
 |-
-|5315 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator open to 0.2563 cm, Cell side collimator OPEN to 2 cm , radiator 3/4" IN , Target is EMPTY  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain,  replace aluminium dump with a half lead brick '''centered 2" from beam''' center [[File:Rate2nC_5315.png|40px]]|-[[File:Run5315_ToF_Histograms.png|40px]]
+|5315 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator open to 0.2563 cm, Cell side collimator OPEN to 2 cm , radiator 3/4" IN , Target is EMPTY  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain,  replace aluminium dump with a half lead brick '''centered 2" from beam''' center [[File:Rate2nC_5315.png|40px]][[File:Run5315_ToF_Histograms.png|40px]]
 |-
 |5316 || || 11.1 MeV , 2 ns pulse width , 300 mA , 200 Hz , Accelerator side collimator open to 0.2563 cm, Cell side collimator OPEN to 2 cm , radiator 3/4" IN , Target is EMPTY  , D30 HV changed -1550V, All other detectors at -1700 V, removed pair spectrometer magnet, poly, and stand,Removed 3rd collimator wall, D30 has NO thick lead curtain, replace  half lead brick with battle ship steel 17" high 24" deep and 4" beam left right [[File:Rate2nC_5316.png|40px]][[File:Run5316_ToF_Histograms.png|40px]]

@@ Line 83: / Line 83: @@
 #The back wall was a source of photons that can be reduced best with blinders
 #The ToF spectrum needs better separation between gamma flash and neutrons, Move detectors back?
-#The tunnel of love reduced the photon singles rate by more than a factor of for D120 & D150
+#The tunnel of love reduced the photon singles rate by about 10% for D120 & D150 (compare runs 5300 & 5301).
 #Opening the collimator slit fully caused gamma flash to appear close to the neutron ToF
 #Neutron singles rate in D225 was within the desired rate of 2e-3 n/pulse for a thorium plate target at 90 degrees to the beam

@@ Line 83: / Line 83: @@
 #The back wall was a source of photons that can be reduced best with blinders
 #The ToF spectrum needs better separation between gamma flash and neutrons, Move detectors back?
-#The tunnel of love improved D150's shielding
+#The tunnel of love reduced the photon singles rate by more than a factor of for D120 & D150
 #Opening the collimator slit fully caused gamma flash to appear close to the neutron ToF
 #Neutron singles rate in D225 was within the desired rate of 2e-3 n/pulse for a thorium plate target at 90 degrees to the beam

@@ Line 100: / Line 100: @@
 = Long run on Thorium=
 = Long run on 1 mg HEU=
 [[2nCor_44#Run_Plan]]

@@ Line 90: / Line 90: @@
 #beam tuning may increase photon flash.
 #determine collimator size to produce photon cone that is contained within the photon dump (blinders)
 =No target run=

@@ Line 88: / Line 88: @@
 #D30's rate decreases by a factor of three for every inch of lead shielding added to the front
 #pair spectrometer magnet has little impact on detector background
 =No target run=