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Follow-up on blinded data in DSTs

Updated on Thu, 2018-10-04 10:44. Originally created by genevb on 2018-06-29 13:53.
This is a follow-up to the topic of what would be blinded from the 2018-06-26 discussion at the joint ABC / CME focus group meeting....

PicoDsts:

These PicoDst branches were proposed by analyzers for blinding, with EventId not set to zero, but replaced by a pseudo event number to be sure event mixing works OK. I'm not sure BField is important to blind as the whole of Run 18 was taken with a single field (and it turns out that the PicoDst maker uses it to project tracks to the EMC), so this will not be blinded.
BLIND 
*Br    1 :Event.mRunId : Int_t mRunId[Event_]                                *
*Br    2 :Event.mEventId : Int_t mEventId[Event_]                            *
*Br    3 :Event.mFillId : UShort_t mFillId[Event_]                           *
*Br    4 :Event.mBField : Float_t mBField[Event_]                            *
*Br    5 :Event.mTime : Int_t mTime[Event_]                                  *

*Br   44 :Event.mZDCx : UInt_t mZDCx[Event_]                                 *
*Br   45 :Event.mBBCx : UInt_t mBBCx[Event_]                                 *
*Br   46 :Event.mBackgroundRate : Float_t mBackgroundRate[Event_]            *
*Br   47 :Event.mBbcBlueBackgroundRate :                                     *
*Br   48 :Event.mBbcYellowBackgroundRate :                                   *
*Br   49 :Event.mBbcEastRate : Float_t mBbcEastRate[Event_]                  *
*Br   50 :Event.mBbcWestRate : Float_t mBbcWestRate[Event_]                  *
*Br   51 :Event.mZdcEastRate : Float_t mZdcEastRate[Event_]                  *
*Br   52 :Event.mZdcWestRate : Float_t mZdcWestRate[Event_]                  *
We also discussed zeroing the vertex X and Y (but not Z, which is needed for analysis), and replacing the track origin 3-vector components with the 3-vector DCA components (because calculating the DCAs is all that these quantities are used for) IF the primary vertex positions gave information about the beam. My homework was to look at the beams from the two species and verify whether distinctive information is there: my conclusion is that one cannot tell the species from the collision vertices, so it appears we need NOT take any further action on these and they can stay unblinded, avoiding changing the PicoDsts:
DON'T
BLIND		 
*Br    6 :Event.mPrimaryVertex.mX1 : Float_t mX1[Event_]                     *
*Br    7 :Event.mPrimaryVertex.mX2 : Float_t mX2[Event_]                     *

*Br   72 :Track.mOrigin.mX1 : Float_t mX1[Track_]                            *
*Br   73 :Track.mOrigin.mX2 : Float_t mX2[Track_]                            *
*Br   74 :Track.mOrigin.mX3 : Float_t mX3[Track_]                            *
There was no trigger information in the PicoDst that needed blinded, from what was discussed. For example, the same trigger IDs were used for both species, while a trigger ID is still needed to know on which events to run the analyses, so there is no reason to blind:
DON'T
BLIND		 
*Br   15 :Event.mTriggerIds : vector mTriggerIds[Event_]       *


MuDsts:

We did not discuss the MuDst, but it would seem that the above-mentioned blinding would be achieved by blinding:
BLIND 
MuEvent.mRunInfo.* (modulo the magnetic field)
MuEvent.mEventInfo.* (modulo a pseudo event ID as already noted)
And perhaps the only trigger and trigger detector info needed to be kept for analysis is the trigger IDs, and the ADC (& pedestal) information used to reconstruct reaction planes (from what I can tell, the ZdcSmd information cannot be used to clearly distinguish the species):
DON'T
BLIND		 
MuEvent.mTriggerIdCollection.mNTriggerId.mId[64]
MuEvent.mZdcTriggerDetector.mZdcSmdEast[16]
MuEvent.mZdcTriggerDetector.mZdcSmdWest[16]
MuEvent.mBbcTriggerDetector.mAdc[48]
MuEvent.mBbcTriggerDetector.mPed[128]
...so the rest of the trigger data could be blinded without concern, as a conservative approach:
BLIND 
MuEvent.mL0Trigger.*
MuEvent.mTriggerIdCollection.*
MuEvent.mTriggerData
MuEvent.mVpdTriggerDetector.*
MuEvent.mMtdTriggerDetector.*
MuEvent.mCtbTriggerDetector.*
MuEvent.mZdcTriggerDetector.*
MuEvent.mBbcTriggerDetector.*
MuEvent.mEmcTriggerDetector.*
MuEvent.mFpdTriggerDetector.*
MuEvent.mFmsTriggerDetector.*


-Gene
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