IDS120j WITH AND WITHOUT RESISTIVE MAGNETS

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IDS120j WITH AND WITHOUT RESISTIVE MAGNETS
PION
AND MUON STUDIES WITHIN TAPER REGION, III
( 20 cm GAPS
BETWEEN CRYOSTATS )


Nicholas Souchlas, PBL
(9/4/2012)
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IDS120j GEOMETRY, WITH/WITHOUT RESISTIVE COILS
WITH 20 cm GAPS
MUONS SPREADING
WITHIN THE TAPER REGION AND BEYOND. MUONS
DETECTED WITHIN 40 cm RADIUS IN z PLANES ALONG
THE TAPER REGION AND BEYOND. MAGNETIC
FIELD FOR IDS120j WITH AND WITHOUT THE RS
MAGNETS WILL BE USED. (ONLY SC MAGNETS ARE
LEFT IN THE GEOMETRY FOR THE MARS
SIMULATIONS). BEAM PIPES WITH TAPERING FROM
z 0.0 cm TO z 1,500 cm BASELINE USED
FOR BOTH CASES ALTHOUGH THE MAGNETIC
FIELD IS NOT 1.5 T AT THE END POINT.

gtSIMULATIONS CODE mars1512
gtNEUTRON ENERGY CUTOFF 10-11 MeV gtPROTON BEAM
POWER 4 MW gtPROTON ENERGY E 8 GeV gtPROTON
BEAM PROFILE GAUSSIAN, sx sy 0.12 cm (P12
POINT)

gtEVENTS IN
SIMULATIONS Np 200,000
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IDS120j GEOMETRY, NO RESISTIVE COILS WITH 20
cm GAPS
SIMULATIONS USING LOWEST
GRADE W BEADS IN SHIELDING ( OF 15.8 g/cc )
BP2 SEGMENTATION STUDIES WITHIN THE FIRST
CRYOSTAT AND RIGHT FLANGE OF Hg POOL INNER
VESSEL.
gtSIMULATIONS CODE mars1512
( USING MCNP CROSS SECTION LIBRARIES )
gtNEUTRON ENERGY CUTOFF 10-11 MeV gtSHIELDING
60 W 40 He ( WITH STST VESSELS) gtPROTON
BEAM POWER 4 MW gtPROTON ENERGY E 8
GeV gtPROTON BEAM PROFILE GAUSSIAN, sx sy
0.12 cm



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IDS120j REPLACING RESISTIVE MAGNETS
AND FILLING UPPER HALF OF Hg POOL WITH
SHIELDING. GENERAL OVERVIEW (LEFT), POOL REGION
DETAILS (RIGHT). 20 cm GAPS

SH3
SH1
SH1A
SH1
SH4
SH2
BEAM PIPE EXTENDS HALF WAY UPSTREAM TO THE POOL
SH1A
Hg POOL
2 cm THICK STST BEAM PIPE
Hg POOL
CRYO4
CRYO3
CRYO2
CRYO1
SH1 10 cm THICK STST RIGHT FLANGE
SH1 2 cm THICK STST OUTER TUBE
Hg POOL STARTS 85 cm AND EXTENDS ALL THE WAY
TO THE END OF THE FIRST CRYOSTAT 370 cm.
SHVS WALLS, Hg POOL VESSEL DOUBLE WALLS, Be
WINDOW, He GAP IN Be WINDOW AND IN HG POOL HAVE
NOMINAL VALUES FOR THEIR THIKNESS. STRESS FORCES
ANALYSIS AND LOCAL DPD DISTRIBUTION WILL BE
USED TO DETERMINE THEIR VALUES.
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IDS120j WITHOUT RESISTIVE MAGNETS.
DETAILS OF THE DOUBLE STST Hg POOL VESSEL
(LEFT, MIDDLE) AND THE DOUBLE
Be WINDOW (RIGHT). 20 cm GAPS

TWO 0.5 cm THICK Be WINDOWS AT THE END OF
CRYO1 WITH 0.5 cm He GAP BETWEEN THEM FOR
COOLING.
2 cm THICK STST INNER Hg POOL VESSEL WITH 1 cm
He GAP FOR COOLING.
10 cm THICK STST RIGHT / LEFT FLANGE OF SHVS4,
SHVS1 / SHVS2 WITH 20 cm GAP BETWEEN THEM.
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IDS120j DETAILS OF THE DOUBLE WALL Hg
POOL VESSEL ENVISIONED BY VAN GRAVE.
( PLOTS ARE FROM VAN GRAVE'S 8 / 9
/ 2012 PRESENTATION )
He GAS WILL BE FLOWING BETWEEN THE TWO WALLS FOR
COOLING. VESSEL FILLED
WITH He COOLED THE BEAM PIPE IN THAT AREA WILL
BE PART OF THE POOL VESSEL
W BEADS FOR SCs SHIELDING. AND REMOVING
THE HEAT LOAD WILL BE A CHALLENGING
TASK. SEGMENTATION ANALYSIS WILL BE PERFORMED TO
DETERMINE THE
AZIMUTHAL
DPD DISTRIBUTION.
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IDS120j FOR THE PIONS AND MUONS
DISTRIBUTIONS STUDIE WITHIN THE TAPER REGION
ONLY THE SCs ARE
PRESENT IN MARS SIMULATIONS LEFT .
BEAM PIPE PROFILE WITH /
WITHOUT RS WITH END OF TAPER AT z 15 m
RIGHT .
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MUONS RADIAL DISTRIBUTION HISTOGRAMS z
(IN m) 1 (BLACK), 5 (RED), 10 (GREEN), 15
(BLUE), 20 (PINK) FOR 15 T ( LEFT )
AND 20 T ( RIGHT ) MAGNETIC FIELD IN THE
TARGET REGION. 40 lt Ekin lt 180 MeV
SUPRESSION
SUPRESSION
PIONS AND MUONS DISTRIBUTIONS
DEPEND ON RELATIVE POSITIONS OF PROTON BEAM
AND Hg JET ( --gt PIONS INITIAL
CONDITIONS ), DECAY ( PIONS ) / GENERATION (
MUONS ) OF PARTICLES, THE MAGNETIC
FIELD. ONE CAN SEE THE EFFECT ( SENSITIVITY )
ON MUONS YIELDS, DISRTIBUTIONS OF A
STRONGER MAGNETIC FIELD IN THE TARGET REGION.
IN BOTH CASES THE TAIL HAS REACH A
LIMIT AT 15 m AND IS CLEARLY MORE SUPRESSED
IN THE 20 T FIELD CASE. ONE CAN ALSO SEE
HOW THE CENTER OF THE DISTRIBITION CHANGES
WITH z ltrgt 5 / 3 cm --gt 10 / 7 cm ( 15 /
20 T ) .
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x/Rap AND y/Rap BOTH 15 / 20
T HAVE ONLY A SMALL DIFERENCE. SMALLER RADIAL
SPREADING WITH 20 T FIELD
FIXED DIFFERENCE 15-20 T. SLOWER DECREASE
BETWEEN 2 AND 4 m. FAST
DECREASE OF r_max/Rap WITHIN FIRST 8-9 m, MUCH
LARGER FOR 20 T FOR 1 -3 m. TAIL PIONS
WILL FOCUS FAST WITHIN 10 m NEED TO
TAKE INTO ACCOUNT THE NUMBER OF PARTICLES
REPRESENTED BY THESE 20 EVENTS, RATIOS
MAY HAVE TO BE MULTIPLIED WITH PARTICLES
WEIGHT FOR 1-20 m POINTS TO EXTRACT
MORE CLEAR INFO. (sig_r/Rap)(15 m/15 T)0.36
(sig_r/Rap)(15 m/20 T)0.34
GAUSSIAN DISTRIBUTION ?
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MUONS DISTRIBUTION HISTOGRAMS IN x, z
(IN m) 1 (BLACK), 5 (RED), 10 (GREEN), 15
(BLUE), 20 (PINK) FOR 15 T ( LEFT )
AND 20 T ( RIGHT ) MAGNETIC FIELD IN THE
TARGET REGION. 40 lt Ekin lt 180 MeV
SUPRESSION
THE CENTER OF THE DISTRIBUTIONS IS IN THE
NEGATIVE x DIRECTION ( -1 ? ltxgt ? 0 cm )
AND DOES NOT VARY MUCH WITH z, IT ALSO LOOKS
LIKE MOST OF THE SUPRESSION IN THE
DISTRIBUTIONS TAILS IS IN THE x DIRECTION
WHEN 15 --gt 20 T. POSSIBLE
CANCELLING EFFECTS BETWEEN POSITIVE AND
NEGATIVE MUONS x DISTRIBUTIONS ?

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POSITIVE PIONS x, y AND r
DEVIATIONS AS FUNCTIONS OF AXIAL DISTANCE.

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x AND y SPREADING HAVE ONLY A SMALL
DIFERENCE. FROM THE RADIAL SPREADING WITHIN
THE FIRST 10 m OR SO IT APPEARS A PORTION
OF THE PARTICLES COULD BE LOST IN THE BEAM
PIPE AND SHIELDING MATERIAL. THE RADIAL SPREADING
HAS REACH ITS LIMIT VALUE OF 11 cm
AT z 10 cm.
SAME CONCLUSIONS AS THOSE FOR POSITIVE
PIONS CAN BE DRAWN FROM ABOVE PLOTS
FOR NEGATIVE PIONS.
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MUONS DISTRIBUTION HISTOGRAMS IN y, z
(IN m) 1 (BLACK), 5 (RED), 10 (GREEN), 15
(BLUE), 20 (PINK) FOR 15 T ( LEFT )
AND 20 T ( RIGHT ) MAGNETIC FIELD IN THE
TARGET REGION. 40 lt Ekin lt 180 MeV
SHIFT
SUPRESSION
THE CENTER OF THE DISTRIBUTIONS IS IN THE
POSITIVE y DIRECTION ( 0 ? ltygt ? 1 cm
INITIALLY). THERE IS A WEAK INCREASE WITH z
FOR THE 15 T FIELD AND A RELATIVELY
STRONGER INCREASE FOR THE 20 T. FROM 1 cm FOR
15 / 20 T TO 2 cm FOR 15 T AND 6 cm
FOR 20 T CASE. IT ALSO LOOKS LIKE MOST OF THE
SUPRESSION IN THE DISTRIBUTIONS TAILS
IS IN THE - y DIRECTION WHEN 15 --gt 20 T.
POSSIBLE CANCELLING EFFECTS BETWEEN
POSITIVE AND NEGATIVE MUONS y
DISTRIBUTIONS ?
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SAME CONCLUSIONS CAN BE DRAWN FROM
ABOVE PLOT FOR NEGATIVE PIONS TOO.
NEGATIVE PIONS x, y AND r
DEVIATIONS AS FUNCTIONS OF AXIAL DISTANCE.

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NUMBER OF PIONS AND MUONS PER INCIDENT
PROTON AS FUNCTIONS OF AXIAL DISTANCE LEFT
AND FOR MUONS ONLY RIGHT .
MOST SIGNIFICANT DIFFERENCE IS IN THE YIELD
OF POSITIVE MUONS (FROM 15 TO 20 T) AND
STARTS AT 10 cm.
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MUONS RADIAL SPREADING HAS A FASTER
INCRAESE WITHIN FIRST FEW METERS SINCE
MORE AND MORE PIONS DECAY TO MUONS
INCREASING THEIR NUMBER AND THEIR SPREADING
.

PIONS AND MUONS RADIAL SPREADING
COMPARISON.
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