R3B Heavy Ion Tracking - GSI Webserver WWW-WIN
R3B Heavy Ion Tracking - GSI Webserver WWW-WIN
R3B Heavy Ion Tracking - GSI Webserver WWW-WIN
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<strong>R3B</strong> <strong>Heavy</strong> <strong>Ion</strong> <strong>Tracking</strong><br />
Roman Gernhäuser, TU-München<br />
Status of the High Rate Diamond Detectors for <strong>Heavy</strong> <strong>Ion</strong><br />
<strong>Tracking</strong> and TOF<br />
• detector concept<br />
• larger area prototypes<br />
• electronics development<br />
• test experiment<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong>
R 3 B (Reactions with Relativistic Radioactive Beams) Setup<br />
∆p/p ~ 10 -4 @ 2.5% accept.<br />
Measurement of all kinematic variables in a HI reaction<br />
Different tasks: High resolution tracking in the super FRS,<br />
radiation hard (SFRS) 10 6 cm -1 s -1<br />
2 x TOF (SFRS – target) (reaction products)<br />
low material budget<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong>
APV APV APV APV<br />
<strong>R3B</strong> Detector Concept<br />
tracking layer:<br />
• 50 x 50 mm, d = 100 µm, PC-CVDD<br />
• 140 µm pitch (125µm strips, 15 µm gap)<br />
• only digital position information<br />
• multiplexed readout in vacuum<br />
timing layer:<br />
• 50 x 50 mm, d = 100 µm, PC-CVDD<br />
• 8 rate matched strips, y information, trigger<br />
• analog preamplification in vacuum<br />
• discriminator @ 5 m distance<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong>
Mean charge [a.u.]<br />
240<br />
200<br />
160<br />
5•10 10 1.5•10 11 2.5•10 11<br />
Dose [ions / mm 2 ]<br />
Status Spring 2007<br />
detailed investigations:<br />
using ~ 40 x 1cm 2 sample detectors<br />
• material properties checked<br />
• radiation hardness proven<br />
• segmentation scheme optimized<br />
• lithography improved (15µm)<br />
• efficiency > 98%<br />
• fast preamps vacuum suited<br />
• good TOF resolution<br />
• 1 st prototype of APV readout<br />
next steps:<br />
intermediate size prototypes<br />
separate detector – electronics<br />
test of high resolution tracking<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong><br />
Energy [ADC ch.]<br />
counts<br />
Time [60ps]<br />
σt= 75 ps<br />
expected<br />
25 ps<br />
ε~98 %<br />
Energy [ADC ch.]
4 prototypes produced<br />
2 operational<br />
lithography under control<br />
Frontside:<br />
128 strips<br />
170 µm wide 20 µm gap<br />
Backside:<br />
16 strips<br />
Larger Area Detector<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong><br />
25.4 mm
128 channels<br />
preamp, shaper,<br />
192 x 25ns<br />
analog pipeline<br />
64 channels front side<br />
64 channels back side<br />
APV Preamplifier Board<br />
input protection<br />
capacitor array<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong><br />
pitch adapter<br />
APV chip
• Existing hardware<br />
• Existing software<br />
• <strong>GSI</strong> support (MBS)<br />
• Compatible to<br />
existing detectors<br />
DAQ<br />
Event-<br />
Builder<br />
SAM3<br />
SAM3<br />
VME<br />
CPU<br />
GTB Readout Scheme<br />
New implementation of<br />
APV state machine<br />
and 12bit ADC<br />
GTB up to 100 m<br />
16 bit, LVDS, 20 MB/s<br />
Bridge Board<br />
FE FE FE FE<br />
Bridge Board<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong><br />
ADCs<br />
GTB<br />
FE FE FE FE<br />
Diamond strips Diamond strips<br />
power supply<br />
trigger in<br />
Flash FPGA clock<br />
Common noise and<br />
zero suppression<br />
not yet implemented<br />
more powerful FPGA
100 µm<br />
diamond<br />
100 µm<br />
diamond<br />
Beam: 600 AMeV 129 Xe<br />
Detector Test @ <strong>GSI</strong><br />
Trigger<br />
scintillator<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong>
APV range<br />
Raw Data<br />
typical multiplicities 4 - 10<br />
multiplexer clock<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong><br />
common<br />
noise
[channels]<br />
APV Channel Korrelation<br />
??<br />
[channels]<br />
8-fold and 2-fold correlations<br />
Could be digital, analog,<br />
or detector problem<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong><br />
Typ multiplicity<br />
3-10 strips<br />
barycenter det2 [190mm]<br />
barycenter det2 [190mm]
pos det2 [190 µm]<br />
Position Resolution<br />
pos det1 [190 µm]<br />
online preliminary result:<br />
intrinsic resolution ~ 100 µm<br />
full detector resolution ~ 500 µm<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong>
TOF measurement<br />
small detector large detector<br />
C = 10pF<br />
50Ω impedance on both sides<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong><br />
C = 70pF<br />
APV impedance matching?
Detector Production<br />
Signal Properties<br />
Task List<br />
• only 50% good detectors (material quality?)<br />
• Some samples show persistent photo current (PPC) after irradiation<br />
• photo lithography (works perfect on 1’’ detectors), large area and<br />
d = 50 µm samples still under investigation .<br />
• bonding on growth side still not reliable<br />
• coupling between channels (locate)<br />
• time resolution worse than expected (detailed investigations)<br />
• walk correction should be possible with APV readout<br />
• new bridge board with faster data transfer and more BG<br />
suppression (barycenter calculation on board....).<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong>
SFP<br />
optical transceiver<br />
New Bridge Board<br />
Micro<br />
Controler<br />
Boot<br />
prom<br />
Latice<br />
ECP2M-50<br />
FPGA<br />
<strong>R3B</strong> - meeting Oct 2007@ <strong>GSI</strong><br />
LVDS driver<br />
ADC<br />
8x12bit<br />
LVDS driver<br />
GTB interface<br />
GTB interface<br />
3,3V
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