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V. Pugatch Kiev Institute for Nuclear Research. CBM Silicon Tracking System. Status of the CBM-02 sensors characterization and n-xyter readout. Thanks to coauthors: J. Heuser 2 , V. Kyva 1 , A. Lymanets 1,3 , Melnyk 1 , V. Militsiya 1 , Yu. Sorokin 1 , V. Zhora 4 1 KINR, Kiev
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V. Pugatch Kiev Institute for Nuclear Research CBM Silicon Tracking System.Status of the CBM-02 sensors characterization and n-xyter readout. • Thanks to coauthors: • J. Heuser 2, V. Kyva 1, A. Lymanets 1,3, • Melnyk1, V. Militsiya 1, Yu. Sorokin1, V. Zhora 4 • 1 KINR, Kiev • 2 GSI, Darmstadt, • 3 now at FIAS, J.W. Goethe University, Frankfurt, • 4 Institute of Microdevices (Kiev) CBM Collaboration Meeting. Split. 06-09.10.2009
New R&D: Agreement ‘KINR-GSI’(not yet completed) • A low-mass mechanical assembly of double-sided silicon microstrip sensors and their connection through analog readout cables to a readout electronics • A quality assurance procedure suitable for a future larger detector module production. CBM Collaboration Meeting. Split. 06-09.10.2009
Mounting CBM02-B1 sensor Supporting frame (AEROPLAST Carbon fiber) has been used to allow bonding from both sides of the double-sided CBM02-B1sensor as well as to provide cooling. Two-layer micro-cables were produced and bonded (IMD, Kiev, V. Zhora) to match the pitch CBM02-B1 sensor: Even strips – to upper layer; odd strips to the bottom layer; - the same structure for p- and n-side of a sensor. CBM Collaboration Meeting. Split. 06-09.10.2009
Sensors characterization • CBM02-B2 sensor has been mounted and connected to a discrete electronics at the readout board. • Tests were performed at KINR using laser pulses (640 nm) and radioactive source. Coincident energy spectra for pairs of adjacent strips. p-strips, irradiation from p-side . Sum of the amplitudes of the signal from alpha –source As a function of the biasing voltage. Notice! Strange behavior at the 3.5 V CBM Collaboration Meeting. Split. 06-09.10.2009
Measurements with radioactive sources Ra-226, 4 lines – alpha-source. Charge, Strip ” k” Test setup at KINR: coincident energy spectra for pairs of adjacent strips. p-strips, irradiation from p-side . Spectrum is deteriorated when a biasing voltage is applied. Unexpected performance in the inter-strip gap Charge, Strip “k+1” CBM Collaboration Meeting. Split. 06-09.10.2009
Measurements with radioactive sources Ra-226, 4 lines – alpha-source. Test setup at KINR: Energy spectra For single p- strips Irradiation from n-side . Spectrum does not show any peak structure even at high voltages. CBM Collaboration Meeting. Split. 06-09.10.2009
Measurements with radioactive sources Ra-226, 4 lines – alpha-source. Test setup at KINR: Energy spectra for single strips. p-strips, irradiation from p-side . Expected performance for the single-strip signals CBM Collaboration Meeting. Split. 06-09.10.2009
Measurements with radioactive source. N-strips Ra-226, 4 lines – alpha-source. Test setup at KINR: coincident energy spectra for pairs of adjacent strips. n-strips, irradiation from p-side . Charge, Strip ” k” Up to 60 V two-dimensional spectra from n-strips have a ‘diagonal’ loci – indication of shortening of n-strips. The spectra are getting expected shape at >120 V biasing voltage applied. Charge, Strip “k+1” CBM Collaboration Meeting. Split. 06-09.10.2009
Measurements with radioactive sources Ra-226, 4 lines – alpha-source. Test setup at KINR: coincident energy spectra for pairs of adjacent strips. n-strips, irradiation from n-side . Charge, Strip ” k” Spectrum does not show peak structure even at high biasing voltage applied. Dead layer at the n-side ~ 20 mu thick ? Charge, Strip “k+1” CBM Collaboration Meeting. Split. 06-09.10.2009
Laser Stand - a part of the Quality Assurance System Software/hardware allows to move a laser beam over the silicon detector surface. Laser Stand (LS) at KINR for testing STS Si-microstrip detector modules laser beam wavelength – 640 nm, diameter of the laser beam spot ~10 µм step in X and Y – directions (15x15 cm2) –10 µм. Response of two adjacent strips: Laser beam was moved from one strip to another. CBM Collaboration Meeting. Split. 06-09.10.2009
Laser beam characterization of CBM-02 sensor Total pulse amplitude from two adjacent strips versus detector voltageshows strange behavior. (laser beam, 640 nm, from the p-side). There are unexpected negative pulses at the some regions of the voltage applied … CBM Collaboration Meeting. Split. 06-09.10.2009
Setting up n-XYTER-based DAQ chain at KINR. So far all the measurements in KINR have been carried out using general-purpose readout electronics. In order to examine the performance of the Silicon Microstrip Deterctors in more realistic conditions we need to use a DAQ chain based on nXYTER. As a cross check and at the first approach we have performed the measurements with the general-purpose readout electronics. DAQ chain in KINR has been assembled and shielded against RF noise. We are currently using (thanks to Walter !) : FEB Rev. C with 1 nX ROC with the newest HW and SW versions (1.7.2.17 and 1.7.1.0 respectively) (V_io=2.5V; MAC address updated)
Setting up n-XYTER-based DAQ chain at KINR. All the software necessary for DAQ has been installed. (GO4, ROClib of different versions...) The software works perfectly with ROC-Simulator. On the histogram: hits per nX channel obtained with rocsimul+go4monitor Current problem: We are not receiving any hit packages from ROC. The most probable reason: nXYTER is not configured properly? – working to find out. (Yes, we were executing setrocdef and setfebdef in rocutil) In near future: – hope to run nXYTER – going to bond CBM02-B2 to nxyter and study it's properties Many thanks to Walter for his great help !
Summary. • Pre-Prototype Detector Modulesupporting frames, sensors, microcables, readout electronics and cooling were tested. • CBM02 first sensor (B1 –type): - Unexpected performance in the interstrip gap for p-strips - field free (~ 20 mu) layer at the p-side ? - Dead layer (~ 20 mu thick) from the n-side ? very similar to the CBM01 sensors (with minor changes) • Supporting frames perfect features (low mass, mechanical rigidity, thermoconductivity, easy connection and geometry shaping etc.,) • Microcables (including double-layer structure) perfect electrical and mechanical features matching CBM request. • N-XYTER readout chain is close to be running at KINR. Bonding to the CBM02 sensors is on the soon agenda. • Real Modules assembly and their Quality Assurance could be provided by KINR in collaboration with IMD (Kiev), IAP (Sumy) and AEROPLAST (Kiev) within the ULISSI R&D project. CBM Collaboration Meeting. Split. 06-09.10.2009