1 / 21

MUON FLUX MEASUREMENTS AT THE LSC

MUON FLUX MEASUREMENTS AT THE LSC. Héctor Gómez Maluenda, University of Zaragoza. hgomez@unizar.es. JRA1-N2 Meeting, Zaragoza, Nov 23 rd 2007. Outline. Introduction Detection system features Preliminary tests at sea level Measurements in LSC Outlook Summary and Conclusions.

mary-gilmore
Download Presentation

MUON FLUX MEASUREMENTS AT THE LSC

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. MUON FLUX MEASUREMENTS AT THE LSC Héctor Gómez Maluenda, University of Zaragoza. hgomez@unizar.es JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  2. Outline • Introduction • Detection system features • Preliminary tests at sea level • Measurements in LSC • Outlook • Summary and Conclusions JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  3. Introduction • Need to check the theoretical value for the muon flux LSC Depth: 2450 mwe Expected Muon Flux: ~3 10-3 m-2 s-1 JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  4. Detection system features • Detectors • 2 Plastic scintillators BICRON BC 408 of 80 x 40 x 5 cm3. • 2 light guides with PMTs coupled to the scintillators. JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  5. Detection system features • Electronic Chain • NIM Fast – Slow standard coincidence system. JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  6. Detection system features • Readout • C-code based acquisition program using a 32 channel I/O digital card. • Storage of the energy of both detectors and time (up to 100 s accuracy) for each coincidence event allowing energy and time analysis. JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  7.  Detection system features Muons produce a coincidence event releasing an energy average of 2 MeV per cm. <E>T~10 MeV Most of the gammas coming from natural background (up to ~3 MeV) release all the energy in one detector  Rejected event. Our set up allows to detect muons coming from a solid angle of ~2 JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  8. Preliminary tests at sea level • We made some measurements in Zaragoza (200 m above sea level) in order to adjust the DAQ (gain, thresholds…) and to check the efficiency of the system. • The total muon flux expected for a 2 solid angle is 125 m-2s-1. • PDG. S. Eidelman et al., Physics Letters B 592, 1 (2004) JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  9. Preliminary tests at sea level • 3 different regions in the spectra - Background region. - Intermediate region. JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  10. Preliminary tests at sea level • 3 different regions in the spectra - Background region. - Intermediate region. -Muon region. JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  11. Preliminary tests at sea level • 3 different regions in the spectra  = 105.64 ± 0.02 (stat.) m-2 s-1 • Systematic errors (~10%): • - Not 2 solid angle. • - Unconsidered shielding. • - Efficiency less than 100%. • - Lose of muons: • No coincidence. • Less energy deposit than expected. Muon Flux COMPATIBLE RESULTS JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  12. Measurements in LSC • Location JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  13. Measurements in LSC • Results: 50.8 days of measurement.  = 3.94 ± 0.02 (stat.) ± 0.4 (sys.) 10-3 m-2 s-1 Slightly higher than expected value WHY? JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  14. Measurements in LSC • A Possible Explanation: Mountain Profile. JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  15. Measurements in LSC • A Possible Explanation: Mountain Profile. PRELIMINARY Hall B 5.04 ± 0.06(stat) ± 0.5(sys) 10-3m-1s-1 +28% Hall A 3.94 ± 0.02(stat) ± 0.4(sys) 10-3m-1s-1 Old Lab 3.59 ± 0.04(stat) ± 0.4(sys) 10-3m-1s-1 -9% JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  16. Outlook • Complete measurements in the Old Lab and Hall B at LSC trying to corroborate and quantify the influence of the mountain profile in the muon flux. • Make a Monte Carlo study to estimate the muon flux in the different locations (ongoing). JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  17. Summary and Conclusions • We developed and tested successfully an experimental set up to measure the muon flux. • The muon flux measured at the Hall A of the LSC seems to be slightly higher than the expected value regarding the depth of the Lab. • A possible explanation for this difference could be the dependence between the muon flux and the mountain profile. • Preliminary measurements in other locations of the LSC and the Old Lab seem to corroborate this theory. • More accurate measurements and Monte Carlo simulations are ongoing to obtain final conclusions. JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  18. MUON FLUX MEASUREMENTS IN THE LSC Héctor Gómez Maluenda, University of Zaragoza. hgomez@unizar.es JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  19. Stability of the Rate Different orientation JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  20. Different Analysis Methods Method i) Chu & Chl > 600 Method ii) Chu & Chl > 170 Method iii) Chu || Chl >170 JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

  21. Different Analysis Methods JRA1-N2 Meeting, Zaragoza, Nov 23rd 2007

More Related