Models: Sources

European Spallation Source-Initiative (ESS-I)

ESS-I workshop on instruments for ESS



This document presents the current data concerning source models for simulations.
[ ILL | SNS | ISIS | ESS-LP ]



ILL moderators

The model is obtained from Maxwellian distributions
Moderator Maxwell parameters
ILL VCS cold source (H1x)
T1=216.8,I1=1.24e+13,T2=33.9,I2=1.02e+13, T3=16.7 ,I3=3.0423e+12
ILL HCS cold source (H5x)
T1=413.5,I1=10.22e12,T2=145.8,I2=3.44e13, T3=40.1 ,I3=2.78e13
ILL Thermal tube (H12, H2x)
T1=683.7,I1=0.5874e+13,T2=257.7,I2=2.5099e+13, T3=16.7 ,I3=1.0343e+12
ILL Hot source
T1=1695,I1=1.74e13,T2=708,I2=3.9e12

McStas component is Source_gen.
Vitess module is source.

References: Ageron and the ILL Yellow Book.


SNS moderators

SNS Home > Components > Moderators > HPTS Design as of 7/31/02 (SCT series) CURRENT

HPTS Design as of 7/31/02
Moderator Material Decoupler Poison Poison Depth Beamline Metrics File Source File
Top Upstream para-hydrogen cadmium gadolinium 27 mm 2 source_sct091_tu_02_1 source_sct091_tu_02_1
Top Upstream para-hydrogen cadmium gadolinium 27 mm 11 source_sct091_tu_11_1 source_sct091_tu_11_1
Top Downstream para-hydrogen none none n/a 5 source_sct21a_td_05_1 source_sct21a_td_05_1
Bottom Upstream water cadmium gadolinium 15 mm 8 source_sct521_bu_08_1 source_sct521_bu_08_1
Bottom Upstream water cadmium gadolinium 25 mm 17 source_sct521_bu_17_1 source_sct521_bu_17_1
Bottom Downstream para-hydrogen none none n/a 14 source_sct41a_bd_14_1 source_sct41a_bd_14_1


Select the S_filename, then give geometry parameters and energy range.


McStas component is SNS_source, using MCNP distribution files (from G. Granroth, SNS)
Vitess module is source.

References:


ISIS TS1+2

Information obtained from ISIS Computing group, using MCNPX.

Target
Face
TS2
Hydrogen
Groove
Narrow
Broad
E1
E2
E3
E4
E5
E6
E7
E8
E9
W1
W2
W3
W4
W5
W6
W7
W8
W9
TS1
H2
CH4
Merlin
Water
Maps
Crisp
Gem
EVS
HET
HRPD
Iris
Mari
Polaris
Prisma
Sandals
Surf
SXD
Tosca

After selecting the Face, define:

Usage explained from the McStas Component manual, p24.

McStas component is ISIS_moderator, using MCNP distribution files, from S. Ansell and D. Champion.
Vitess module is source, using MCNP distribution files and analytical formula.

ESS Long-Pulse TS

Technical details of the ESS sources, as of 2004, are to be found in the ESS Project Volume III Update:
The original design for ESS-LP moderators was modeled using the formula from F. Mezei (see ref below).

Moderator
Parameters for a 5 MW source
General parameters
size=0.12, l_low=0.1, l_high=10, dist=2, xw=0.06, yh=0.12, freq=50, branchframe=0.5,
n=20, n2=5, d=2e-3, branch1=0.5, branch2=0.5
Ambiant H2O
I0=13.5e11, T=325, tau=80e-6, tau1=400e-6, tau2=12e-6, chi2=2.5, I2=27.6e10
liquid para-H2
I0=6.9e11, T=50, tau=287e-6, tau1=0, tau2=20e-6, chi2=0.9, I2=27.6e10
para-H2 and H20 side-by-side
not modelled

McStas component is ESS_moderator_long.
Vitess module is source.

References:

Other references:


E. Farhi
Rencurel, Vercors, France -  Sept. 11-15, 2006 Modified: July 6th, 2006