Presentation is loading. Please wait.

Presentation is loading. Please wait.

Over the Last Couple of Weeks Gave talk at CMS Run Coordination Workshop –See Jay’s talk Two CSC Online computers have been replaced in the past two weeks…

Similar presentations


Presentation on theme: "Over the Last Couple of Weeks Gave talk at CMS Run Coordination Workshop –See Jay’s talk Two CSC Online computers have been replaced in the past two weeks…"— Presentation transcript:

1 Over the Last Couple of Weeks Gave talk at CMS Run Coordination Workshop –See Jay’s talk Two CSC Online computers have been replaced in the past two weeks… –Got lucky: happened between fills… no beam time lost 11 Nov 2010G. Rakness (UCLA)1

2 “Runtime” critical machines Cannot run without… –csc-fed[1,2] –csc-tf –ttc-csc –HV computers (running SLC3, hot swap exists in ISR) Process should be able to move to another host –csc-sv Run control configuration should not depend on these hosts –csc-pc[1,2]  as luck would have it, csc-pc1 died today –csc-daq (local DAQ) –csc-dqm (local DQM) Not used at run time… –csc-dcs-pc[1,2] (used for XMAS monitoring) –Rest of DCS computers are going to set up to have hot swaps over the Dec-Feb Technical Stop… 11 Nov 2010G. Rakness (UCLA)2 I made this list yesterday and presented it to the online software group…

3 Trigger timing 11 Nov 2010G. Rakness (UCLA)3 Status as of 17 August 2010: CSC’s prefiring at few-parts-per-mill… (All analysis by Chris) Had aimed for 204…  Should aim to hit 204.5… Had aimed for 205…  205 is still OK… Clean up the early ones… Scheme: clean up early CSC’s, leave the late ones alone…

4 Tightening CSC Trigger Timing 20 Aug 2010G. Rakness (UCLA) 4 After Plot average AFEB time per chamber Changes implemented 29 Oct 2010 C. Farrell (UCLA) ME2/1, ME3/1, ME4/1 Other chambers Before

5 Subtlety to previous plots… There are 3 outliers which are outside the range of these plots which are late by ~1bx... –ME-1/3/31 = 26.4nsec –ME+2/1/13 = 25.4nsec –ME+3/1/4 = 26.1nsec In all cases, the parameters that were changed to shift 2nsec touch the boundaries which separate the “good” from the “bad” regions: –alct_tx_clock_delay=16 and alct_tx_posneg=1 and alct_tof_delay=12. As it turns out, this region is hard to deal with, and needs to be handled in a case-by-case basis. –Some on the edge are faster than others on the edge (with the same parameters) by 1bx.  Thus, we speed up the trigger by 1bx on those following chambers by setting alct_tx_posneg=0 and subtracting 1 from match_trig_alct_delay (and alct_bx0_delay) 11 Nov 2010G. Rakness (UCLA)5

6 Some Heavy Stable Charged Particle papers “Properties of hadron distributions in reactions containing very heavy quarks,” J. D. Bjorken, Phys. Rev. D 17 (1978) 171. “Hunting Half-integer charged, heavy hadrons from higher dimensions,” G. Ingelman and C. Wetterich, Phys. Lett B174 (1986) 109. “Search for Heavy Stable Charged Particles in 1.8-TeV pp-bar Collisions at the Fermilab Collider,” F. Abe et al., Phys. Rev. Lett. 63 (1989) 1447. “Limits on the production of massive stable charged particles,” F. Abe, et al., Phys. Rev. D 46 (1992) 1889. “Search for Long-Lived Charged Massive Particles in pp-bar Collisions at s=1.8TeV,” D. Acosta, et al., Phys. Rev. Lett. 90 (2003) 131801. “Search for Long-Lived Charged Massive Particles with the D0 Detector,” V. M. Abazov, et al., Phys. Rev. Lett. 102 (2009) 161802. “Search for Long-Lived Massive Charged Particles in 1.96 TeV pp-bar Collisions,” T. Aaltonen, et al. Phys. Rev. Lett. 103 (2009) 021802. “Stable Massive Particles at Colliders,” M. Fairbairn, et al., Phys. Rept. 438 (2007) 1. 11 Nov 2010G. Rakness (UCLA)6

7 Some things I learned from those papers… Every paper calls these particles something different… –CDF: Heavy Stable Charged Particle, CHArged Massive Particles (CHAMP), Massive Stable Particles (MSP) –D0: Charged Massive Stable Particle (CMSP) –Fairbairn, et al.: Stable Massive Particles (SMPs) –CMS: Heavy Stable Charged Particle (HSCP) Many many many models which either go beyond or supersymmetrize the standard model expect to see heavy stable charged particles of some sort… –Conserved (or almost conserved) global quantum number –Suppressed decay due to coupling or kinematics –Can be strongly interacting (R-hadrons) or weakly interacting… … see next page… 11 Nov 2010G. Rakness (UCLA)7

8 An incomplete list of models includes… Supersymmetry –Minimally Supersymmetric Standard Model –Gauge Mediated Symmetry Breaking –Split Supersymmetry –Super Gravity Extra dimensions: KK-parity Magnetic Monopoles … 11 Nov 2010G. Rakness (UCLA)8

9 Basic expectations of HSCP Low velocity Large p T Muon-like penetration –Note: this last is driven by kinematics… Massive object colliding with small object cannot lose much energy…  A model-independent search should look for these “smoking guns” As experimental techniques developed over time, they grew to look for… –Signals in the muon detectors –TOF discrimination –High p T –Large dE/dX I thought it was interesting that the analysis paper from CMS preferred to focus on a model-dependent search, focusing on dE/dX… 11 Nov 2010G. Rakness (UCLA)9

10 Some biases one might expect from the models Pair production preferred –Prompt single production from standard model particles implies vanishingly small production rate Single particle production as decay product from another particle… Strongly interacting heavy particles (i.e., R-hadrons) contain most of the energy in the jet –Single particle-dominated jet… 11 Nov 2010G. Rakness (UCLA)10 hep-ph/0611040

11 And now for something completely different… CLCT muonic timing plan of attack Did I get the sign wrong? –Test before and after with equation including bx and sub- bx changes… If I were to get the sign right (correct offline, if needed)… –Can I understand the posneg and rx communication parameters “bad zone” Fix and automate I’ll start working on that this week… 11 Nov 2010G. Rakness (UCLA)11

12 Greg “To do” Near term Understand and fix CLCT muonic timing Work on CSC dE/dX –Start from Chris’ code and plot of SCA data for muons and compare with MC –Goal (eventually): Implement in HLT, together with timing cut? Figure out list of CEO’s for Spring 2011 Make sure others do CEO: HV state from ON  STANDBY in between fills… Online Software: prepare for Dec-Feb technical stop Longer term items at 904 TTCci consolidation with Calibration Runs Online software –Put ALCT firmware database check into ALCT firmware write routine –Resurrect ALCT self-test –ALCT hot-channel mask in xml file/config DB –Expert config check –Configuration check with separated DMB and CFEB 11 Nov 2010G. Rakness (UCLA)12


Download ppt "Over the Last Couple of Weeks Gave talk at CMS Run Coordination Workshop –See Jay’s talk Two CSC Online computers have been replaced in the past two weeks…"

Similar presentations


Ads by Google