Beam Profile Monitor Using Pixel Detector

Transcription

1 Beam Profile Monitor Using Pixel Detector - Crossing angle, z location, B-field, and readout electronics - Fujikawa, Hashimoto, Tani, Yamamoto, Yokoyama (Tohoku University) Ikeda (Space Institute) Snowmass 2005, Colorado

2 Hit Location on the Pair Monitor y hit point on monitor p t φ r O x ρ(cm) = p t(mev/c) 3B 0 (Tesla), φ = 3B 0(Tesla)L(cm) p z (MeV/c) L : distance to IP ρ measures p t and φ measures p z. For L = 176 cm, p z 350 MeV/c φ π. The larger B 0 L, the greater the dilution of pattern.

3 Hit Location on the Pair Monitor (w/ Xing angle) y hit point on monitor hit point on monitor p t O x p t Crossing angle θ X gives horizontal p t of θ X p z /2 (comparable to original p t if θ X 30mrad). The focused paritcles get horizontal p t hit the monitor (more hits on monitor).

4 0mrad Xing, z=4m, B=4T (ILC params)

5 20mrad Xing, z=4m, B=4T (ILC params)

6 Seelect sensitive regions One example: Form R vp = blue pink + red

7 Xing = 0mrad, z = 400 cm 20 readings/train Fix σ x, Vary σ y = nσ 0 y Form ratio R pv = L 1 + L 2 H 1 + H 2 Try different L 1,2,H 1,2 regions

8 Xing = 7mrad, z = 400 cm

9 Xing = 20mrad, z = 400 cm

10 Xing = 20mrad, z = 176 cm

11 σ y resolutions Tesla-500 parameters, 20 readings/train Average resolution of 2 σ y and 4 σ y 3T 4T 5T z = 400cm 0mrad 11% 13% 13% z = 400cm 7mrad 9% 11% 12% z = 400cm 20mrad 22% 19% 28% z = 176cm 20mrad 12% 15% 20% Caveat : Resolution depends on the selection of sampling regions.

12 Effect of Tail - how big is the tail? - First preliminary look - Fraction of total bunch charge out side of the rectangular box of K (collimation depth) Tesla collimation depth =13σ x, 80σ y Fraction outside 7σ x,48σ y Assume a gaussian with 10 σ y, 0.1% area (Very uncertain!)

13 Effect of Tail (beam halo) - First preliminary look - No tail ILC beam params 0mrad crossing z=400cm 0.1% tail (y) (adding a gaussian with 10 σ y core ) No significant difference. Further study to be done.

14 The σ y resolution is worse when distance from IP is larger. B field is larger. crossing angle is larger. σ y resolution same for θ X =1 7mrad. Things to do: Use correct B field (edge effect, Q-magnet, compensating coil etc.). More study of the pattern (location of information). Measurement of other beam parameters (σ x, horizontal shift, azimuthal tilt of bunch etc.). Robustness of measurement (non-gaussian beam shape, tail, halo etc.)

15 Pixel Readout Electronics Pixel electronics for warm machine Measure time and pulse height of each hit. 4-point sampling (250ns apart). σ t 30ns achieved ( goal). Survived 2MRad (goal). Cannot be used for cold machine, since For warm machine, hit rate 0.5 hits/pixel/train. For cold machine, it will be 15 hits/pixel/train. too much. Solutions Count the number of hits and store it locally on each pixel. Read out in train gap (or during the train if possible). Threshold is applied insensitive to X-rays etc. Digital read out insensitive to RF pickups.

16 Readout electronics for cold LC 1. pixel : 0.4x0.4 mm 2. 3D pixel sensor is being designed/fabricated. 2. TMSC has 2.54 by 1.27 cm 2 chips : sensor size by 54 pixels/sensor bit gray code counter parallel outputs/sensor 1728 bits/line MHz transmission 43 µs/readout ( 20 readouts possible during train, in principle)

17 Pixel electronics (readout)

18 C=0.4pF Pixel circuit R1 1P 4P R0 1P 4P W1 1P 4P W0 VDD 1P 4P SELB M=10 W=3u L=0.4u Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 W1 CARRY DOUT AOUT2 AOUT1 IN MONSW ON OUT S3 IN MONSW ON OUT S2 IN MONSW ON OUT S1 IN MONSW ON OUT S0 N SHPR1 OUT P VH VM VL VH4 VM4 VL4 S3 3 S2 2 S1 1 S0 0 A1 A0 DEC2 TPENB D2 is for future use. W3 W2 SEL SEL SELB M=10 SEL SELB TPENB D2 D1 D0 W=3u L=0.4u VSS CHAIN3 A1 A0 XSEL YSEL DIN DOUT CK WR INIT DEC MONOUT W0 WSEL R1 R0 RSEL RB D0 D1 D2 D3 D4 D5 D6 D7 G0 G1 G2 G3 G4 G5 G6 G7 Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 W1 Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 W0 WSEL R1 R0 RSEL RB D0 D1 D2 D3 D4 D5 D6 D7 G0 G1 G2 G3 G4 G5 G6 G7 Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 W1 Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 W0 WSEL R1 R0 REGBNK4 REGBNK4 REGBNK4 RSEL RB D0 G0 D1 G1 D2 G2 D3 G3 D4 G4 D5 G5 D6 G6 D7 G7 Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 W1 Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 2 FB4 VLS VL VM VL2 VM2 1 VP VH VH2 VP AOUT1 1 SW0 IN OUT ON C=0.1pF R3 R2 SEL A1 A0 DEC2B SEL W0 WSEL R1 R0 REGBNK4 RSEL RB D0 D1 D2 D3 D4 D5 D6 D7 TP TPENB BONDING PAD M=1 C=0.01pF W=1.2u L=0.4u VSS C=0.01pF AIN PrC2 VH VM VL 1 2 RF2 OUT VH VM VL C=0.4pF N W=0.72u M=1 L=0.24u W=0.72u L=0.24u SHPR1 M=1 OUT P VH VM VL VTH R=10K P IN N VH VH4 COMP0 OUTB VL VL4 ENB CK RB G0 G1 G2 G3 G4 G5 G6 G7 G0 G1 G2 G3 G4 G5 G6 G7 COUNT8 B0 B1 B2 B3 B4 B5 B6 B7 CARRY VH3 VM3 VL3 VH4 VM4 VL4 VDD AOUT2 VSS CARRY VH1 VM1 VL1 Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 XSEL YSEL DIN DOUT CK WR INIT WSEL3 WSEL2 WSEL1 WSEL0 RSEL3 RSEL2 RSEL1 RSEL0 AIN RESET 4P ENB 1P 1P

19 Readout electronics status and plan 1. Conceptual design completed. (Ikeda + 2 students) 2. Basic simulations and noise estimations done. 3. Finish circuit design by end summer Layout by outsourcing. 5. Submit for fabrication (MOSIS) end Test the circuit 2006 spring. 7. Bump bond to prototype sensor (company?).