UA9 Status & Plans UA9 Status & Plans U. Wienands, SLAC U. Wienands, SLAC LARP LTV @ CERN LARP LTV @ CERN Acknowledgment to W. Scandale, Spokesperson of UA9, for providing me with most Acknowledgment to W. Scandale, Spokesperson of UA9, for providing me with most of the material. of the material. U. Wienands, SLAC 1 LARP CM15, 02-Nov-10
UA9 Goals UA9 Goals • UA9 is a rather large multi-lab collaboration: UA9 is a rather large multi-lab collaboration: • – CERN, BNL, INFN(4 labs), IHEP, Imperial, JINR, PNPI, SLAC • Its goals are to: Its goals are to: • – Characterize crystals suitable for beam collimation in the SPS and, ultimately, the LHC – Proof of principle and demonstration of collimation efficiency in the SPS – Pending results, extension to mount a beam-collimation experiment with crystals in the LHC. U. Wienands, SLAC 2 LARP CM15, 02-Nov-10
Sep 2010 H8 telescopes Sep 2010 H8 telescopes trigger XY XY UV XY scintillators plane planes plane plane d2 d3 d1 [~10m] d4 [~10m] beam 25 cm crystal position Image with the TPC-GEM � 5 planes altogether (10 silicon strip sensors) June 2010 each plane provides 2 co-ordinates: XY or UV � UV plane = XY plane rotated through 45 0 (resolves ambiguities for multiple hits / trigger) Proton channeling � 65 m downstream: TPC- GEM and Medipix (fast scan) + Planar GEM 72 µ rad deflection U. Wienands, SLAC 3 LARP CM15, 02-Nov-10
Si Strip Detector Si Strip Detector » CMS LHC Si strip readout system » Provided by Imperial College group » DAQ, calibration, raw data and recorded » Tested in H8 in June one telescope working suitable for UA9 physics investigation U. Wienands, SLAC 4 LARP CM15, 02-Nov-10
H8 Results H8 Results S. Montesano U. Wienands, SLAC 5 LARP CM15, 02-Nov-10
UA9 (SPS) Setup in 2010 UA9 (SPS) Setup in 2010 New goniometer and 2 new crystals Roman pot without detectors U. Wienands, SLAC 6 LARP CM15, 02-Nov-10
UA9 Setup (cont UA9 Setup (cont’ ’d) d) Tal 2 station U. Wienands, SLAC 7 LARP CM15, 02-Nov-10
Roman Pot #2 Roman Pot #2 Very close to TAL, better position to see channeled beam! No detectors yet Place to install 4 Medipix (2 Horiz and 2 Vert.) Relevant to measure channeled beam direction in conjunction with the RP1 (from centroids) U. Wienands, SLAC 8 LARP CM15, 02-Nov-10
Beam Collimation Beam Collimation Beam axis Beam propagation Impact Collimator Core Core parameter Particle Unavoidable losses Primary Primary halo (p) halo (p) Secondary Secondary � halo halo p Shower Shower Tertiary halo Tertiary halo � Impact parameter collimator p � 1 µ m Primary Secondary e collimator p Absorber Absorber Shower Shower SC magnets e Super- and particle conducting physics exp. magnets R.W. Assmann W/Cu W/Cu CFC CFC replace by crystal U. Wienands, SLAC 9 LARP CM15, 02-Nov-10
Channeled Beam on MediPix Channeled Beam on MediPix U. Wienands, SLAC 10 LARP CM15, 02-Nov-10
2009 Result (Crystal #1) 2009 Result (Crystal #1) W. � Scandale • Rotate crystal, detect • Rotate crystal, detect et al. / PLB Crystal no. 1 (strip) (nuclear-) scattering (nuclear-) scattering 692 (2010) • Loss reduction in • Loss reduction in 1 expt. data channeling mode ( � 5) channeling mode ( � 5) 2 simulation – smaller than in MonteCarlo simulation ( � 36) • • Alignment errors induced Alignment errors induced by by – vertical torsion of the crystal – inaccuracy of the Goniometer • Deflection efficiency for • Deflection efficiency for crystal 1 and 2 : (75±4)% crystal 1 and 2 : (75±4)% and (85±5)% and (85±5)% U. Wienands, SLAC 11 LARP CM15, 02-Nov-10
2010 Result: Crystal #3 2010 Result: Crystal #3 • Loss reduction in • Loss reduction in channeling mode ( � channeling mode ( � 16) 16) 1 expt. data – smaller than in 2 simulation MonteCarlo simulation ( � 33) – larger than in crystal 1 ( � 5) • Small variations of • Small variations of the deflection angle the deflection angle in different scans in different scans – [better control of the alignment errors] U. Wienands, SLAC 12 LARP CM15, 02-Nov-10
Angular Scan of Crystal #3 Angular Scan of Crystal #3 • • Crystal at 4.5 � Crystal at 4.5 � – Nuclear loss ratio � 35 – Channeling at 100 µrad • • Crystal at 6 � Crystal at 6 � – Nuclear loss ratio � 8 – Channeling at 60 µrad U. Wienands, SLAC 13 LARP CM15, 02-Nov-10
Collimator Scans Collimator Scans Spray of the LHC collimator Detector U. Wienands, SLAC 14 LARP CM15, 02-Nov-10
LHC Collimator Scan of Crystal 3 LHC Collimator Scan of Crystal 3 Channeling efficiency 80% U. Wienands, SLAC 15 LARP CM15, 02-Nov-10
TAL 2 Scans TAL 2 Scans • Dispersive area of the SPS sensitive to diffractive Dispersive area of the SPS sensitive to diffractive • events events – channeled particles don’t hit TAL2 (on 1 st path) Halo leakage Spray of TAL2 TAL2 BLM U. Wienands, SLAC 16 LARP CM15, 02-Nov-10
Collimation leakage in a high-dispersive area Collimation leakage in a high-dispersive area � A) tail of the circulating beam (r.u.)=count rate/circulating intensity AM=amorphous orientation ! fast depletion in channeling mode CH=channeling orientation ! linear descent of the population in amorphous orientation (or with the tungsten scatterer) � B) multiple Coulomb scattering ! fast depletion by high probability of prompt channeling at the first crystal hit ! slow depletion due to multi-turn hits of the amorphous primary (very slow extraction) � C) shadow of the absorber ! low population due to low probability of nuclear interaction in channeling mode ! off-momentum halo due to diffractive hits with the amorphous primary and TAL U. Wienands, SLAC 17 LARP CM15, 02-Nov-10
UA9 Main Results UA9 Main Results • Crystal collimation works very well based on Crystal collimation works very well based on • channeling process channeling process – Optimal crystal alignment easily detected and achieved – Collimation leakage in amorphous orientation larger than in channeling • Collimation leakage rate reduced by more than a Collimation leakage rate reduced by more than a • factor of 5 at the TAL2 in the dispersive location factor of 5 at the TAL2 in the dispersive location (sextant 5, position 22) (sextant 5, position 22) – Nuclear loss rate (including diffractive) strongly depressed – In channeling versus amorphous mode : � 16 in multi- turn (SPS) U. Wienands, SLAC 18 LARP CM15, 02-Nov-10
UA9 Plans UA9 Plans • Complete the runs in 2010 • Complete the runs in 2010 – (pending request of one additional shift of 8 h to partly compensate the two UA9 shifts used to fill LHC) – Main goals • Improve the estimate of the collimation efficiency • Improve loss map detection in the dispersive area • Test the remaining crystals • Add one or two Medipix in the Roman pot 2 (–> 2011) • Test with IONS Pb82 • • Extension of the UA9 apparatus in the 2011 winter shutdown Extension of the UA9 apparatus in the 2011 winter shutdown – Replace gonios 1 and 2 with more accurate short goniometers (suited for LHC) – Complete the beam loss detectors (a coincidence telescope everywhere) – Fill the RP2 with 4 medipix and 2 fiber hodoscopes – Add SPS collimators and loss detectors in 2 more areas to introduce betatronic aperture restrictions. • Request submitted for similar run time in SPS and H8 next year. • Request submitted for similar run time in SPS and H8 next year. – endorsed by the CERN SPSC U. Wienands, SLAC 19 LARP CM15, 02-Nov-10
SPS Results vs vs LHC Requirements LHC Requirements SPS Results U. Wienands, SLAC 20 LARP CM15, 02-Nov-10
Road Map towards an LHC Expt. Road Map towards an LHC Expt. • Crystals in preparation at PNPI and INFN-Ferrara to be tested in H8 • Crystals in preparation at PNPI and INFN-Ferrara to be tested in H8 • Goniometer in preparation with and industrial partnership with • Goniometer in preparation with and industrial partnership with CINEL, to be tested in H8 CINEL, to be tested in H8 – IHEP also proposed to build new goniometers for SPS, should fit LHC also • Special instrumentation [loss detectors and mini-Roman pots] in • Special instrumentation [loss detectors and mini-Roman pots] in preparation at CERN with the help of INFN and Imperial College to be preparation at CERN with the help of INFN and Imperial College to be tested at the SPS tested at the SPS • Simulation! • Simulation! – Simulation working group to be formed (CERN, INFN, IHEP, …) – important for both the SPS expts as well as any planning for LHC • Layout of a possible installation at the LHC • Layout of a possible installation at the LHC – There are flanges in the LHC available, details to be worked out, close coordination with LHC ops and LHC collimation group needed. U. Wienands, SLAC 21 LARP CM15, 02-Nov-10
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