Target Shaft Simulationwith G4Beamline

M. Apollonio, IC

Motivations:

• Assess better orientation for secondaries production

• Assess flaws in capture dependent on target position

• work in progress ...

• a bit of work to generate the secondaries and select only those potentially reaching Q1 bore

10 mm

10 mm

XZ

25 deg

Q1-TGTaxis

25 deg

lostto Q1

secondariesproduction20<theta<30propagation toplane Aacos(Pz/Ptot)>20&& acos(Pz/Ptot)<30

rotation &propagation to plane B

A A

B

C

shift & align with Q1-TGT axis

LONG SLIM

25 deg

25 deg

FAT SHORT

TILTED TGT

Tgt_long_slim_rot0: y:x Nprimaries=100M

Tgt_long_slim_rot0: x {abs(y)<.5 mm} Nprimaries=100M

Tgt_long_slim: y:x rotation 25 deg + shift 4.226

At Q1 plane, Q1 bore

Tgt_tilt25_rot0: y:x Nprimaries=10M

Tgt_tilt25_rot0: x {abs(y)<.5 mm} Nprimaries=10M

At Q1 plane, Q1 bore

Tgt_short_fat_rot0: y:x

Tgt_cyl_rot0: y:x

shape primaries(p) Dx(mm) h(mm) Q1-bore x-section(mm^2) scal fact Q1-bore resc Statuscyl 100M +/-3 4 1464 24 6 8784 short fat 100M +/-5 4 1714 40 10 17140 long slim 100M +/-.5 4 15977 4 1 15977 tilt+25 (\) 100M +/-2.56 4 3092 20.48 5.12 15831 tilt+10 100M +/-1.36 4 6010 10.885 2.7212 16354 tilt-25(/) 100M +/-2.56 4 3300 20.48 5.12 16896 tilt-10 100M +/-1.36 4 6061 10.885 2.7212 16493 long slim 500M short fat 500M +/-5 4 8184 40 10 16368 cyl 500M tilt+25 500M tilt+10 500M fullcyl 5M +/-3 4 194 24 6(x20) 23280 fullcyl 100M

lostto Q1

C

shift & align with Q1-TGT axis

Q1

CAVEAT: take this numbers with a pinch of salt but …

10M beam protons produce:155K secondaries [20,30]degof which only ~16K go throughthe tgt window and reach the Q1 bore

Message: what a wasteof statistcs !!!

Q1 Q1 bore

A

the idea is assuming a cylindrical simmetryand try to enrich the samplepointing at Q1by rotating theevents

(x,y,Px,Py)

(xr,yr,Pxr,Pyr)

I am at this stage: I can create the enriched sample BUT I noticed somestrange shapes of y vs x distribution.I am scared something not right in the re-enrichment of the sampleI am checking it

Once solved I can - shoot these particles into the beamline- rotate the target (see examples next page)- shift the target (and study misalignment)

shape primaries(p) Dx(mm) h(mm) Q1-bore x-section(mm^2) scal fact Q1-bore resc Statuscyl 100M +/-3 4 1464 24 6 8784 Fshort fat 100M +/-5 4 1714 40 10 17140 Flong slim 100M +/-.5 4 15977 4 1 15977 Ftilt+25 (\) 100M +/-2.56 4 3092 20.48 5.12 15831 Ftilt+10 100M +/-1.36 4 6010 10.885 2.7212 16354 Ftilt-25(/) 100M +/-2.56 4 3300 20.48 5.12 16896 Ftilt-10 100M +/-1.36 4 6061 10.885 2.7212 16493 Flong slim 500M Rshort fat 500M +/-5 4 8184 40 10 16368 Rcyl 500M Rtilt+25 500M Rtilt+10 500M Rfullcyl 5M +/-3 4 194 24 6(x20) 23280 Ffullcyl 100M R