29 ottobre 2007Torporkov visit Finned Tube to increase target density? Openable cell for p p Ideas...

29 ottobre 2007 Torporkov visit

Finned Tube to increase target density?

Openable cell for p↑p↑

Ideas to increase cell thickness

Test on the finned Injection Tube

Ciullo G.

29 ottobre 2007 Torporkov visit

The openable cell

• Openable Cell to inject pbar @ AD

Y = 100, x = 50 mm

• Closed cell, square 10x10 mm,

5 m teflon foil.

Sampling tube

Injection Tube

29 ottobre 2007 Torporkov visit

Estimation of the target thickness• Thickness (tc) of the cell

• tc [atom/cm2]

• Cell Geometry: square 10x10 mm, length 400 mm

– IHERMES-ABS = 6.5 • 1016at/s then tc=8.81 • 1013at/cm2

• Some ideas “appear” in order to increase tc?!

2C

tot

LItc

TubeEstBRPABSLL CCCC .2/2/totC

cmin unit length

3.51sl

4.34

'-12

s

l

sl

AA

M

TC

3,94 3,94 5,83

04,181,41

32,11

1

1,04

29 ottobre 2007 Torporkov visit

Lower conductance thicker Target• Lowering the ABS injection Tube Temperature

Target thickness vs ABS injection tube temperature

6

7

8

9

10

11

12

25 50 75 100 125 150 175 200 225 250 275 300 325

ABS feeding tube Temperature [K]

Inte

gra

ted

tar

get

th

ickn

ess

[10

13 at

om

/cm

2 ]

20%

30%

10%

29 ottobre 2007 Torporkov visit

Lower conductance thicker Target• Longer ABS injection Tube

Target thickness vs ABS tube length

6

7

8

9

10

11

12

8 10 12 14 16 18 20 22

ABS feeding tube Length [cm]

Inte

gra

ted

tar

get

th

ickn

ess

[10

13 at

om

/cm

2 ]

10%

20%

29 ottobre 2007 Torporkov visit

Lower conductance thicker Target• ABS injection Tube with fins

cmin unit length

3.51sl

4.34

'-12

s

l

sl

AA

M

TC

Finned tube

8,00E+13

8,50E+13

9,00E+13

9,50E+13

1,00E+14

1,05E+14

1,10E+14

0 5 10 15

Number of fins

thic

kn

es

s (

at/

cm

q) 18 %

23 %AI 'Incoming atoms

Outcoming atoms

29 ottobre 2007 Torporkov visit

Finned tubes

29 ottobre 2007 Torporkov visit

Test on the finned tubes

Q = (Pcal-P cv) Ccal = (Pcv-P RF) Ccv

29 ottobre 2007 Torporkov visit

Measure of Ccal

• Misura di Ccal

• Evacuazione di Vcal da Ccal

. inoltre ;

cal

cal

cal

calcalcal V

V

C

CVC

0 20 40 60 80 1002

3

4

5

6

7

8

9

Data: aug17Cmeas_PbmModel: ExpDec1Equation: y = A1*exp(-x/t1) + y0Weighting: y Instrumental Chi^2/DoF = 0.09545R^2 = 1 y0 0.23024 ±0.01451A1 8.63199 ±0.01113t1 69.76054 ±0.24462P

bm (

mba

r)

time (min.)

Pbm ExpDec1 fit of aug17Cmeas_Pbm

29 ottobre 2007 Torporkov visit

Measured of Q calibrated

6,0x10-5 8,0x10-5 1,0x10-4 1,2x10-4 1,4x10-4 1,6x10-4 1,8x10-4 2,0x10-4

4,0x10-4

6,0x10-4

8,0x10-4

1,0x10-3

1,2x10-3

1,4x10-3

1,6x10-3

inear Regression for Qcalc0fins230_qCAL:Y = A + B * XWeight given by Qcalc0fins230_ErrQcal error bars.

Parameter Value Error------------------------------------------------------------A -7,2146E-5 1,96151E-6B 8,28848 0,01727------------------------------------------------------------

R SD N P------------------------------------------------------------0,9999 6,72786 3 0,00892------------------------------------------------------------

Qca

lib (

mb

ar

l/s)

Pcv

(mbar)

qCAL Linear Fit of Qcalc0fins230_qCAL

Calibrated througput measured with a 1% error

0 fins for 23 august

Q calibration curve derived for all finned tubes

29 ottobre 2007 Torporkov visit

Fixing in mind problems

• We can measure – The Qincoming is well

calibrated measurement

– Then derive the tc

• To derive the tc, from data

» We need Qincaming (2%)

And

» Coutcoming (30%)

29 ottobre 2007 Torporkov visit

I measured and see MC simulation

0 2 4 6 8 10 126,5x10-4

7,0x10-4

7,5x10-4

8,0x10-4

8,5x10-4

9,0x10-4

9,5x10-4

1,0x10-3

1,1x10-3

1,1x10-3

Q a

tom

ic b

ea

m (

mb

ar

l/s)

Number of fins

Q atomic beam measuredQ normalized as A

0 and derived as Q~A

29 ottobre 2007 Torporkov visit

Surviving atomic beam

29 ottobre 2007 Torporkov visit

s

l

A

A

sl

AA

M

TC

-1

0

2

13.51sl

4.34

'

Ccv measured and calculated

%]30 of [

%]2 of [

4.2 error

err

P

QC

cv

calmeas

Next step: use the baratron to measure PCV ?!

29 ottobre 2007 Torporkov visit

Thickenss of the cell

2C

tot

LItc

29 ottobre 2007 Torporkov visit

Conclusions

• To increase the target density– Lower temperature of ABS injection tube

– Mechanical complication and vibrations.

– Longer tube– Test on the recombination and transport required?

– Finned tube– Due to the azimuthal motion of the focused atomic beam

» Reduced target thickness.