1 / 55

Improved Cherenkov Threshold detectors for heavy-ions experiment

Improved Cherenkov Threshold detectors for heavy-ions experiment. P. Martinengo,CERN – High-pT Physics at LHC,Tokaj’08. Can we extend the ALICE PID for hadrons above 5 GeV/c ?. ALICE Club - May 2, 2005 Paolo Martinengo. What means “high-pT“ ?. HMPID 3 σ p/K limit. HMPID TDR.

gerard
Download Presentation

Improved Cherenkov Threshold detectors for heavy-ions experiment

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Improved Cherenkov Threshold detectors for heavy-ions experiment P. Martinengo,CERN – High-pT Physics at LHC,Tokaj’08

  2. Can we extend the ALICE PID for hadrons above 5 GeV/c ? ALICE Club - May 2, 2005 Paolo Martinengo

  3. What means “high-pT“ ?

  4. HMPID 3σ p/K limit HMPID TDR U. Wiedemann, Heavy Ions Forum, 10 February 2004

  5. yesterday HMPID 3σ p/K limit HMPID TDR

  6. start of LHC yesterday HMPID 3σ p/K limit HMPID TDR

  7. first HI collision ? start of LHC yesterday HMPID 3σ p/K limit HMPID TDR

  8. Conclusion The HMPID is an excellent detector with a wrong name !

  9. Home work • Identify hadrons with pT ≥ 10 GeV/c track-by-track • Inclusive measurement, particle yields, • especially protons • Weak identification, i.e. Π,K – protons • can be enough

  10. Nγ(cm-1eV-1) ~ sin2θ (HMPID 1.5 cm liquid C6F14)

  11. ~ 2m

  12. LHCB RICH1 2.4 m • LHCB RICH2 2.0 m • BTeV RICH2 3.0 m • COMPASS > 3.0 m • CBM ~2.5 m • All fixed-target !

  13. “The examples set forth show the great importance which the radiation caused by particles moving at a speed greater than that of light has acquired in experimental physics. Even so, we have not by a long way exhausted all the possibilities for theirpractical use. There can be no doubt that the usefulness of this radiation will in the future be rapidly extended.” End of Čerenkov’s Nobel lecture (1958)

  14. ITC Improved Threshold Cherenkov or TIC Threshold Imaging Cherenkov ?

  15. Nice detector but the radiator is too long ( 1m for <6> γ’s )

  16. Theγ’s yield is too low but compact, simple layout well known and mastered technology θc is not measured butγ’s are associated to tracks arobust w.r.t. high multiplicity, noise Is it possible to improve the γ’s yield ?

  17. Yes, it is CaF2 IP C4F10 HMPID CsIphoto-cathode

  18. Quartz cut-off

  19. The HADES RICH HMPID’s brother, both sons of RD26

  20. 1.5 m

  21. Radiator thickness 36 to 65 cm, 12 to 22 γ’s

  22. C4F10 radiator

  23. Can we do better ?

  24. Yes, we can Window less ! CF4

  25. CF4 + CsI give 40 γ’s with 50 cm radiator !

  26. CF4 transparent down to 110 nm !

  27. Why not a GEM detector ? (perhaps with the ALTRO R/O) Nucl. Instrum. Methods Phys. Res., A 535 (2004) 324-329 Nucl. Instrum. Methods Phys. Res., A 523 (2004) 345-354

  28. CF4 radiator

  29. Interesting but not exactly what we want …

  30. DOUBLE RADIATOR TIC Window less ! CF4 C4F10 CaF2 window

  31. C4F10 + CF4 radiators But Čerenkov angles are very similar ! ( 3o and 1.8o)

  32. This would work but it is not elegant C4F10 CF4

  33. DOUBLE RADIATOR TIC Window less ! CF4 C4F10 CaF2 window

  34. 50 cm + 50 cm ~ 10 cm C4F10 CF4 ~2.5 cm ~3 cm

  35. First results from “test beam” 50 cm + 50 cm # of photons Total charge C4F10 C4F10 + CF4

  36. Single radiator TIC CaF2 IP C4F10 HMPID CsIphoto-cathode

  37. SIMULATION Cherenkov photons chamber Mirror (Giacomo Volpe)

  38. SIMULATION 5 GeV/c pions, 366 charged pads 3 GeV/c pions, 189 charged pads 10 GeV/c pions, 564 charged pads

  39. Blob diameter for C4F10, pad size = 0.8x0.8 cm2

  40. Nikolai Smirnov, Yale Univeristy More ideas… AeroGel, 10cm UV Mirror, spherical shape in ZY Double sided Read-out plane Triple GEM foils with CsI 50 cm CF4 gas CaF2 Window Y 50 cm X C4F10 gas R position: 500 cm. Bz: 0.5 T Z Particle track & UV photons

  41. Simulation for high Pt π+ Flat mirror Spherical mirror AeroGel, 10cm UV Mirror, spherical shape in ZY Double sided Read-out plane Triple GEM foils with CsI CF4 gas CaF2 Window C4F10 gas R Z In saturation: <N ph.e.>  25. (C4F10); 30. (CF4)

  42. A. Di Mauro et al, Presented at the Vienna Conf. on Instrum; to be published in NIM Thick GEM with resistive electrodes (RETGEM)- a fully spark protected detector Principle of operation Geometrical and electrical characteristics: Holes diameter 0.3-0.8 mm, pitch 0.7-1.2 mm, thickness 0.5-2 mm. Resitivity:200-800kΩ/□ Kapton type: 100XC10E 30mm or 70mm

  43. Fully spark -protected Summary of the main results obtained with kapton RETGEMs 1 mm thick Energy resolution ~30%FWHM for 6 keV Discovery: kapton can be coated with CsI and have after high QE QE~30% at λ=120nm Filled symbols-single RETGEM, open symbols –double RETGEMs Stars-gain measurements with double RETGEM coated with CsI layer. 15 min continues discharge With increase of the rate the amplitude drop, but now discharges

More Related