Line B preparations

1
Line B preparations

• Hardware issues
• Install Fast Kicker (up to 200 mC/sec).
• Reinstall Line B transport.
• Modify line B current limiters to average over 20
  sec
• Improve access to LD2 pit for target installation
  and operation
• Radiological issues
• Shield line C to allow beam delivery to line C
  with area C with beam in line B.
• Establish operation procedures to stay below
  category 3 nuclear facility radioisotope limits

2
Source time constants
3
Line B/Area B
SD2 Source

• Already in place
• Shielding
• Power
• Water cooling
• Cryogenics
• Proton beamline

800 MeV protons from fast kicker
4
New UCN source
UCN Storage Bottle
UCN Guide
Removable Tungsten Target
Beryllium Neutron Reflector
5
Kicker requirements
6
Kicker is budgeted for 2002 by DP (for proton
radiography)

• gt30 Hz operation
• 6.5 mC/pulse
• 200 mC/sec

7
LD2 pit access (other options)
Possible routes
8
Line C access issues
Shield Wall
Access gate
9
Shedule for target changes
?t Dt Status Cat3 Value   90
days 90 days on 0.561 120 days 30
days off 0.240 210 days 90 days on 0.710
240 days 30 days off 0.373 330 days 90
days on 0.823 360 days 30 days off 0.480
450 days 90 days on 0.923 480 days 30
days off 0.580 570 days 90 days on 1.024
600 days 30 days off 0.677 690 days 90
days on 1.118 720 days 30 days off 0.774  
Table A6.1. Buildup of activities in the SD2
source with 4 mA average beam current. Each beam
cycle is assumed to be 90 days of beam on
followed by 30 days of beam off. The source
becomes a Cat 3 facility when the Cat 3 value
reaches 1.0. The values given assume 90 beam
availability in Line B and 90 accelerator beam
availability for a total beam duty factor of 81.
Eric Pitcher, LANCE 12
10
RADIONUCLIDE INVENTORY IN UCN SOURCEAFTER 4
MONTHS CONTINUOUS BEAM AT 10 mA
  Nuclide Activity (Ci) Cat-3 TQ (Ci)
Ratio   Be 11 0.0028 1.36 0.0021 B
12 0.0028 3.80 0.0007 C 15 0.0028 4.00 0.0007 P
32 0.0140 12.00 0.0012 P 33 0.0243 94.00 0.0003 S
35 0.0138 78.00 0.0002 Br 76 0.0590 560.00 0.000
1 Rb 83 0.0693 400.00 0.0002 Y
88 0.0491 280.00 0.0002 I 124 0.0084 2.40
0.0035 I 125 0.1238 0.56 0.2210 I
126 0.0087 0.46 0.0189 I 131 0.0028 0.92 0.0031 Ba
128 0.2502 1900.00 0.0001 Ba131
0.4411 1860.00 0.0002 La132 0.4606 2000.00 0.0002
Ce134 0.6607 1540.00 0.0004 Ce135 0.6327 1580.00
0.0004 Ce139 0.7986 3200.00 0.0002 Pm143 0.7792 26
00.00 0.0003 Pm144 0.0518 480.00 0.0001 Sm145
0.8497 3600.00 0.0002 Eu145 3.5471 640.00
0.0055 Eu146 4.1010 400.00 0.0103 Eu147 4.6163 176
0.00 0.0026 Eu148 0.3719 380.00 0.0010 Eu149 2.89
45 6800.00 0.0004 Gd146 2.9755 740.00
0.0040 Gd147 3.7807 860.00 0.0044 Gd148
0.0147 0.08 0.1796 Gd149 4.9906 2200.00
0.0023 Gd151 2.7625 4000.00 0.0007 Gd153 1.7407 1
040.00 0.0017 Tb147 1.1065 3800.00
0.0003 Tb149 3.4432 3400.00 0.0010 Tb150 2.8977 4
400.00 0.0007 Tb151 5.2456 1700.00 0.0031 Tb153 6.
2479 6000.00 0.0010 Tb154 0.4981 640.00 0.0008 Tb
155 8.8578 8800.00 0.0010 Tb156 0.1583 500.00 0.
0003 Dy155 8.5373 4000.00 0.0021  
Nuclide Activity (Ci) Cat-3 TQ (Ci)
Ratio   Dy157 9.5397 5600.00 0.0017 Dy159 5.1626 2
400.00 0.0022 Ho159 11.6990 108000.00
0.0001 Er161 11.6210 6600.00 0.0018 Tm162 13.3640
42000.00 0.0003 Tm166 19.0580 920.00
0.0207 Tm167 16.4900 2800.00 0.0059 Yb166 18.251
0 840.00 0.0217 Yb169 18.5870 1640.00 0.0113 Lu16
9 18.8290 1540.00 0.0122 Lu170 21.2370 500.00 0.04
25 Lu171 23.0670 1400.00 0.0165 Lu172
4.7172 480.00 0.0098 Lu173 3.8144 3000.00
0.0013 Lu177 0.5365 3400.00 0.0002 Hf170 16.960
0 2800.00 0.0061 Hf172 2.4085 94.00 0.0256 Hf17
3 23.0190 3200.00 0.0072 Hf175 17.3140 2000.00
0.0087 Hf178 0.0018 10.40 0.0002 Hf181 1.0501 760
.00 0.0014 Ta172 14.8510 15800.00
0.0009 Ta173 18.5090 9800.00 0.0019 Ta174 18.9990
19200.00 0.0010 Ta175 21.4650 3800.00 0.0056 Ta
176 24.0650 1200.00 0.0201 Ta177 23.9440 54000.00
0.0004 Ta179 4.4791 30000.00 0.0001 Ta180
9.7901 2000.00 0.0049 Ta182 4.5080 620.00
0.0073 Ta183 10.9580 3600.00 0.0030 Ta184
3.3412 1080.00 0.0031 W 176 15.0540 42000.00
0.0004 W 177 16.4740 11400.00 0.0014 W 178
23.7700 4600.00 0.0052 W 181 31.5430 13000.00
0.0024 W 185 58.1480 1380.00 0.0421 W
187 387.4810 2200.00 0.1761 Re181
5.2186 2200.00 0.0024 Re182 1.1864 1380.00 0.000
9 Re182 1.1864 500.00 0.0024 Re184 1.4115 900.00
0.0016

• Both spallation products and capture play a role
• Many small contributions
• Some important cross sections are not measured
  (187W)
• Steve Wender is working on the same problem for
  target-4.
• 2 target changes per year is possible

 
Eric Pitcher, LANCE 12
11
Some Conclusions

• Line B operation at 5 ma was routine in LAMPF
  days
• All the parts have been found
• In house expertise exists
• Nuclear facility problems are solved by reducing
  the average current to 4 ma and replacing the
  tungsten annually (biannually if necessary)
• No rate problems (experimental duty factor helps)
• Access problem is solvable
• Minimal impact on PRAD and Lujan can be achieved
  with a fast kicker
• Line C access while source is running
• We can use different pulses from target 1 (Lujan
  target)
• We are well on our way to the worlds highest
  density UCN source.

LAMPF users manual