NIKHEF –D0 meeting, June 6, 2001 Freya Blekman, NIKHEF Amsterdam SMT pedestal management Weekly NIKHEF – NIJMEGEN – D0 meeting June 6, 2001 Freya Blekman

NIKHEF –D0 meeting,June 6, 2001

Freya Blekman, NIKHEF Amsterdam

SMT pedestal managementWeekly NIKHEF – NIJMEGEN – D0 meeting

June 6, 2001Freya Blekman

Summary:Outline of current SMT statusWhat is the next step?SDAQ vs. PDAQYet again: DatabasesThe smt_ped_tools Some results



SMT status (current)100% of the SMT is now cabled95 % of the barrels has been read outFor the F-disks and H-disks, this is a bit lower (around 90%)Still some HV problems, nothing major.Still only running in full-readout mode.



What is the next step?We can now only run whilst reading out all (=800,000) channels of the SMT. This load is not possible for the DAQ (nor will it ever be)SMT will eventually be running in sparse mode‘sparse’ = with pedestal subtraction on the

svx readout chip (~= ADC) and zero-surpression.



What to do: get those Pedestals!Every channel has its own ADC.The pedestal values have only been measured in lab, and even there not very well.When downloading the chip, the pedestals can be set.Pedestal values are retrieved (per channel) in the calibration database and in the online (=‘hardware’) database



Pedestal measurementAt D0, there are two ways to measure the pedestal values of the silicon

1. Take data and look at the average data per channel (= Primary Data Acquisition)

2. When not running, put charge on every channel and do a raw pedestal measurement. (=Secondary Data Acquisition)



SDAQ vs. PDAQ (1)

PDAQ + : Use the data you already have to compensate. ‘Standard’ way to do it.

PDAQ - : You need data ! (and lots of it)

PDAQ - : Cannot readout full SMT unless sparse mode: will only be reading out channel with hit and two neighbors.



PDAQ vs. SDAQ (2)

SDAQ + : It’s relatively quick.(few hours)

SDAQ - : It’s not clear that charge deposition on Si strips has the same result as real life.

SDAQ - : Remove SMT from global run.

SDAQ - : Program still very unreliable(for instance, it ignores the 9th chip on 9-chip

ladders. 50% of the SMT barrel detectors are 9-chip ladders.)



Several SDAQ runs (unbiased ladders)Database problems (solved now)smt_ped_tools (in cvs)

ROOT-based guiCreate_ntuple program

SMT_pedestals.root

Some small macros

Last few weeks:



create_ntuple.xCPP codeUses 2 packages:

D0omORACLEConnects to ORACLE calibration DB

HepTuple Creates root files

Creates root ntuple



create_ntuple.x (2)Why not directly in root?Too much trouble with TSQL classes in root. TSQL works (after a lot of work) on linux, when you have administrator privileges.One of the CDF ORACLE gurus recently (last month) got it working at fnal.I decided that it wasn’t worth wile trying, you don’t want to connect to the database every time anyway.



Smt_ped_gui.CUses ROOTROOT has gui classesIs essentially a big root MacroPlots averages as a function of run number.Options for HDI type selection



Smt_ped_gui/rootMacros/Ready:

Channel maps (semi-interactive)

Near future:Pedestals as a function of integrated luminosityis dependent of availability of1. My time2. Luminosity data (Mike Begel)



Results (1)

Direct output of

smt_ped_tools/

smt_ped_gui.C



Results (2)Run 121545Ladder type

Barrel 4Layer 2Ladder3

Double-sided, 6 svx chips

one of the detectors closest to (0,0,0)



Results (3)Run 121545Ladder type

Barrel 4Layer 3Ladder3

Double-sided, 9 svx chips

SDAQ 9th chip problem visible

Documents

NIKHEF –D0 meeting, June 6, 2001 Freya Blekman, NIKHEF Amsterdam SMT pedestal management Weekly NIKHEF – NIJMEGEN – D0 meeting June 6, 2001 Freya Blekman