Trigger Cross Section Monitoring at the CMS Experiment

1. Trigger CrossSection Monitoringat the CMS Experiment Richard Ruiz 2007 September 13th University of Chicago

2. Outline • Motivation for monitoring trigger cross section • Trigger Cross Section Monitoring at CDF (XMon) • Consumer Client & Fitter • Trigger Cross Section Monitoring at CMS (TXMon) • Introduction to XMon at CMS • Implementing XMon Fitter (My Project) • Future Plan for TXMon at CMS Richard Ruiz

3. Motivation(Why we monitor Trigger Cross Section?) • The probability of a certain reaction can be expressed in terms of physics cross section, σp, a proportionality const. with dimension of area • Ex. At Tevatron Run II, for pp->Z->eeσp ∙ B ~ 270pb (Measured Constant) • Trigger Cross Section, σt, is defined as: • σt = Linst, (Trigger Rate) (Inst. Luminosity) • Ideally triggers contain all signal and no ‘noise’ • σt(Linst) = σp = constant , • However, in practice σt varies as a function of Linst dN dt Richard Ruiz

4. Motivation con’t • High-Energy Hadron Collider experiments like CDF, DØand CMS need triggers to filter the event data withsubstantial reduction factors • Very large beam crossing frequency: fTev= 2.5MHz (396ns), fLHC=40MHz (25ns) • Large Hadron-Hadron cross section • Not all data can be recorded... But we can ~100Hz • Trigger monitors are important • To ensure only interesting data is being recorded • CDF’s XMon is a working example of a trigger monitor which records and displays σt(Linst) Richard Ruiz

5. Trigger Cross Section Monitoringat CDF (XMon) • XMon Online Consumer Monitor • XMon Online Consumer Client • Collects trigger and lumi information fromConsumer Server Logger (CSL) • Tabulates, returns trigger status and alarms if necessary • XMon Fitter • Plots and statistically fits tabulated data • Returns .html file with plots and statistical data Richard Ruiz

6. Implementing Trigger Cross Section Monitoring at CMS • Based on CMS internal note 2007/025, CMShas decided to implement CDF’s XMon at CMS under the name TXMon • TXMon was to be established in two phases • TXMon Fitter (XMon Fitter) • Mostly experimentally independent • TXMon Source & Client (XMon OCC) • Experimentally dependent • Not yet started Richard Ruiz

7. TXMon Fitter • Same function as XMon • Plot, fit and generate .html files • What makes TXMon different from XMon is that • … runs on both 32-bit AND 64-bit CMSSW Env. • … generalized for n triggers and n trigger levels • … more optional output • … more user friendly (for general usage) Richard Ruiz

8. TXMon Fitter Examples • Generated by using CDF XMon root files • Identical, minus aesthetic changes, to XMon Fitter Richard Ruiz

9. Conclusion of Summer • Trigger monitoring system based off of CDF’s XMon is currently worked on and made available for CMS • σt vs. Linst fitting software has already been made andis ready for use from CMS CVS • Future plans include: • TXMon Consumer development will be started soon • Effort to put scalar information in event stream in ongoing • First chance for live test will be Cosmic Run December • LHC slated to go online Mid~Late 2008 Richard Ruiz

10. A Word of Thanks • Prof. Kim for this opportunity • Ms. Marilyn Smith • Prof. Kaori Maeshima for this project • Dr. Kevin Berkett & Dr. Alan Stone for their help • Dr. Matt Worcester & Prof. David Saltzberg • Oringal CDF XMon developers • Dr. Charles Plager & Dr. Nagesh Kulkarni • Original XMon Fitter developer & current maintainer Richard Ruiz

11. Richard Ruiz