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CBM-XYTER. specialities and possibilities in high intensity proton-beam. G. Vesztergombi. CBM Collaboration Meeting Dresden, 27 Sept. 2007. OUTLINE. Introduction: an invitation for brainstorming Proton beam at CBM FAIR Total cross-section trigger at SPS CERN
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CBM-XYTER specialities and possibilities in high intensity proton-beam G. Vesztergombi CBM Collaboration Meeting Dresden, 27 Sept. 2007
OUTLINE Introduction: an invitation for brainstorming Proton beam at CBM FAIR Total cross-section trigger at SPS CERN Tagged neutrino beam for LHC Conclusions
DETNI-A 157Gd/Si Detector Module Goals • 108 n/sec in 100 cm2 • with 2 views, 2 hit/strip:400 MHz strip hit rate • with 5 Byte/hit:2 GByte/sec data Consequences • 128 channel ASIC • 20 chip/module • 20 MHz/chip • 100 MByte/chip 100 mm slide courtesy C.J.Schmidt
CBM-XYTER at FAIR Time structure difference between p and A beams High PT selection
AA collision: <Ntrack> = 3000 <Dt> = 1000 ns pp collision: <Ntrack> = 3 <Dt> = 1 ns pp AA x x x x Identical occupancy in AA and pp per microsec but 1000 times less in pp in nanosec window x x x x x x x x x x x x x x x x x x x x x x x x or x x x x x x x x x x x x x x x x x x x x x x Strip readout Pixel readout required
p p p trans trans trans g E >= p >= 0 long Lab g E Beam Lab High transverse momentum means high 3-momentum Illustration for mid-rapidity at sqrt(s) 7 and 14 GeV ( ) ( ) ( ) E g gb 0 Lab p = long gb g 0 0 0 0 1 • 3.5 1.5 5.25 • 2.0 7.0 • 3.0 10.5 • 90 6.6 1.5 9.9 • 2.0 13.2 • 3.0 19.8
No need for pixel detector for pp, pA high PT Less than 3 hits per cell: (x,y) and (u,v) gives unique solution Question: radiation hardness Assuming 1011 proton/s beam and 1% target interaction one gets in average 1 event/nanosec. Using 3ns time-window one can on-flight identify high PT (i.e. high momentum) tracks Event-building: select all hits which are compatible in time with the triggering 3ns window. Of course, one assumes that all particles are running with c and the Time-of-Flight correction for each channel is applied.
pp, pA physics Search for jet-quenching at SPS energies Quark Matter, Shanghai 2006
Total cross-section trigger Idea (without XYTER) was proposed in 1st FutureDAQ workshop in Munich 25-26.03.2004.
Beam Target NEAR FAR Valid interaction amin SHINE TPC experiment less than 107 proton/sec
TRIGGER First level: ANTI ( BEAM+NEAR+FAR) ACCEPT: No continuation for BEAM particle in NEAR module or multiple track in NEAR CORRECTIONS: elastic scattering with FAR NEAR inefficiency interaction in NEAR
Prototyping possibilities in SHINE/NA61 at SPS • Moderate beam intensity < 107 p/s during the spill • For identification of beam particles one needs only • XYTER cell of 5*5 cm2 surface with x and y readout • The number of strips depends on the requested resolution: • pitch=100 m in 5 cm requires 4 chips for x and y, respectively, • if one uses the DETNI 128 channel ASIC chip. • In total 8 times 8 = 64 ASIC chips would be required. • Test can be done in autumn 2008 or 2009. If sensors and xyter ASIC chips would be available, KFKI-RMKI could design and produce the interface.
LHC tagged neutrino possibility Slow beam-dump Total fill about 1015 proton , extraction time 3 hours: 1011 proton/s Secondaries with few hundred GeV: 1012 p/s decay probability: 10-3 Number of decay muons at tagging station: 109m/s Ideal rate for XYTER Assumption: “point-like” proton beam target , i.e. interaction point is known with reasonable accuracy. Much less load (faster extraction) for neutral K beam.
Unknowns: decay point: ZD and momenta: Pp,Pm,Pn Shielding Decay zone Z XYTER-wall
Unknowns are only the momenta: PK,Pp,Pm,Pn Decay zone Shielding MAGNET XYTER-wall Possible e,m identification
Expected UNK-Serpukhov rates Expected LHC rates Neutrino energies upto TeV cross-section increase High tagging efficiecy + Large detector 10-100 ev/s
Conclusions One can propose very interesting unique applications for XYTER: -in short timescale: SHINE total cross-section trigger -in medium: CBM proton physics -in long-range: LHC tagged neutrino from beam-dump
Understanding Data Acquisition System for N-XYTER www.gsi.de/documents/DOC-2007-Aug-28-2.ppt