1 / 11

Relative Luminosity Analysis from PHENIX

Relative Luminosity Analysis from PHENIX. RIKEN BNL Research Center KAWABATA TAKAHIRO. Instruments. GL1P scaler - crossing-by-crossing scalers for 120 crossings (60 crossings in run 2) - live time only - consists of 4 channels M.B. ( BBCLL1 NTCwide )

wren
Download Presentation

Relative Luminosity Analysis from PHENIX

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. Relative Luminosity Analysis from PHENIX RIKEN BNL Research Center KAWABATA TAKAHIRO

  2. Instruments GL1P scaler - crossing-by-crossing scalers for 120 crossings (60 crossings in run 2) - live time only - consists of 4 channels M.B. (BBCLL1NTCwide ) NTCnarrow / BBCLL1 / ZDC (N&S) • Luminosity monitors • BBCLL1 (|Z| < 75 cm) • NTCwide • NTCnarrow (|Z| < 40 cm) • ZDC NTCS NTCN BBCN

  3. Relative luminosity • no critical item for AN measurement in run-2 • important for ALL measurement in run-3 • 10–4 level precision required for sub-% level asymmetry measurement • normalization in the cross section measurement stability of each luminosity monitor ? • which is the best ?

  4. Scaler Counts GL1P counts vs Crossing number - #10 and #30 … large emittance - #15-19 … abort gap (Yellow) - #55-59 … abort gap (Blue) Only NTC counts beam-gas events. ZDC has low statistics.

  5. Specific Luminosity • Specific Luminosity • Normalized and plotted as a function of crossing number • Specific luminosity fluctuates by 2-5%. • NTCn is less stable. - only NTC counts beam-gas events. • ZDC has low statistics.

  6. RZDC/BBC RBBC/NTCn Fill Number Systematic Error on Relative Luminosity Ratio between GL1P channels must be one. - Shown with the statistical errors by solid circles and lines. Evaluate for random classification.- All bunches were randomly sorted into Group A and B. - Repeat the calculation 400 times. - Shown by shaded area. Systematic error has fill dependence. - ~0.3% for good fill. - Improve by adding all fills up to ~0.2%.

  7. Time Dependence • Spin relative luminosity RXY is plotted as a function of time. - solid lines .. Statistical error - shaded region .. Systematic + Statistical • Each point shows 10,000-sec time slot. • Background colors indicate fills. • RXY has a fill dependence. RZDC/BBC RBBC/NTCn Time (DD/MM)

  8. Correlation between Specific Luminosities • Correlation between spe. lumi. are plotted. • Fluctuation of spe. lumi. is not important. • Systematic errors depend on widths of loci.

  9. Dependence on Z-vertex width • Differences in specific luminosities are plotted as a function of the Z-vertex wdith. • Dependence on Z-vertex width is not clear. • Bunch selection by Z-vertex width did not work well.

  10. Bunch Selection Several bunches with the bad spe. lumi. are excluded - shaded region …. before the selection - black line …. after the selection - red line … statistical error - solid circle … RXY Bunch sel. slightly improves bad fills, but not good fills. Results on RXY are ….- NTCn/M.B. … 1.0005 +/- 0.10% - BBC/M.B. … 0.9974 +/- 0.36% - ZDC/M.B. … 0.9981 +/- 0.37% - BBC/NTCn … 0.9969 +/- 0.41% - ZDC/NTCn … 0.9975 +/- 0.44% - ZDC/BBC … 1.0007 +/- 0.15%by summing up Run40117-40655. RBBC/NTCn RZDC/BBC Fill Number

  11. Summary • GL1P data from PHENIX were analyzed for relative luminosity study. • Systematic error has a fill dependence. - ~0.3% for good fill, 0.15% for Run40117-40655 - Small dependence on Z-vertex width - Slightly improved by bunch selection • Procedure for fill diagnosis should be established.

More Related