CTP offline issues R Lietava 13112007 CTP offline

CTP offline issues R. Lietava, 13/11/2007 CTP offline issues 13/11/07

Outlook • • • Configuration file - Partition Counters – Cross section Interaction record – Pile up CTP data to ESD Trigger inputs - CTP Trigger inputs - detectors CTP offline issues 13/11/07 2

Configuration file: Start of Run ECS OC DB STARTPartition(name. cfg) SHUTTLE CTP proxy CTP offline issues TRIG DB DCS FXS 13/11/07 3

Configuration file Partition configuration: Interaction 1: Logical function of 4 inputs from VALID. CTPINPUTS Interaction 2: Logical function of 4 inputs from VALID. CTPINPUTS 1. CLASSname: TRIGDESCRIPTOR, CLUSTER, PFPROTECTION, BCMASK, ALLRARE. . . 50. CLASSname: TRIGDESCRIPTOR, CLUSTER, PFPROTECTION, BCMASK, ALLRARE *** TABLES: VALID. CTPINPUTS, VALID. CLUSTERS, VALID. PFPROTECTIONS, VALID. BCMASKS TRIGDESCRIPTOR = Logical function of inputs from VALID. CTPINPUTS CLUSTER, PFPROTECTION, BCMASK from TABLES. PRESCALER will not be in configuration file since we may change it during the RUN. CTP offline issues 13/11/07 4

Counters: Start of Run xsec DIM client ECS Open file (<7) STARTPartition(runnum) CTP proxy CTP offline issues Start counters CTP DIM server CTP File server 13/11/07 5

Counters: End of Run xsec DIM client ECS Close file STOPPartition(runnum) DCS FXS CTP proxy Stop counters CTP DIM server Shuttle OCDB CTP offline issues 13/11/07 6

Counters data • Counters read via. VME at CTP CPU ( not part of ‘normal’ data flow) • Data volume: 50 classes* 7 counters=350 words • Read 1 per min => 350*60=82 k. B/hour (to allow for RUN fragmentation and control counter overflow) • Data flow: - CTP -> DCS FXS ->SHUTTLE->OCDB • Counter data to be saved at RUN level in OFFLINE CTP offline issues 13/11/07 7

Interaction records Aim: to have full interaction history ± 88 μs for every event recorded by DAQ • Interaction = 2 different interactions as two independent functions of (first) 4 L 0 inputs are to be defined • For each interaction type and event ID (BC) are recorded • Interaction record = list of interactions in an ORBIT, up to 254 interactions per ORBIT • For each DAQ event the interaction records from 2 ORBITS before and 2 ORBITS after are to be added to the event trigger data => Interaction records part of ‘normal’ data stream CTP offline issues 13/11/07 8

CTP data to ESD Trigger and cluster mask or classes. CTPinoffline ‘normal’ language as in config file 13/11/07 issues 9

Trigger Inputs - CTP Options: SSM in BC mode : low data rate, adjacent BC ok, data transfer similar to DAQ RAW SSM in event mode: data rate ok, adjacent BC ok, data transfer similar to DAQ RAW L 2 a software trigger: data rate ok, no adjacent BC, data over DDL L 2 a any message: CTP dead time doubled, major project development, data over DDL Data transfer similar to DAQ RAW = Direct registration of CTP data in MSS with a registration in the Ali. En catalogue CTP offline issues 13/11/07 10

Trigger inputs - detectors • The trigger inputs recorded in the subdetector readout is the most natural way of providing the required data. • The inputs should be part of ESD. CTP offline issues 13/11/07 11

Summary • • • Configuration file (Partition); ok Counters – Cross section; ok Interaction record – Pile up; ok CTP data to ESD; ok Trigger inputs – CTP; see physics board decision • Trigger inputs – detectors; check status CTP offline issues 13/11/07 12

Back up CTP offline issues 13/11/07 13

Cross section and Luminosity • if you know L, you can calculate σ • if you know σ, you can calculate L CTP counters provides information about the number of interactions N(ΔT) http: //epweb 2. ph. bham. ac. uk/user/pedja/alice/: : CTP preliminary design review; Cross section calculation CTP offline issues 13/11/07 14

Trigger Class Logic and Counters • σclass - uncorrected cross section for class ‘class’ • NXa, NXb – counters at level X=[0, 1, 2] before and after vetoes (see picture). Formula assumes counters are cleared at the beginning • L – luminosity http: //epweb 2. ph. bham. ac. uk/user/lietava/alice. html Offline procedure for the cross Section calculation CTP offline issues 13/11/07 15

SSM - current mode • Records unbiased 1 M of BC = 27 milisec • Time to readout SSM ~ 2 sec • Suitable for trigger inputs study: 100 k. Hz of interaction rate => 1 M/400 = 2600 interactions • 1 k. Hz DAQ rate => 26 readout events, but biased by trigger selection • RND CTP trigger (special run) => 26 unbiased readout events but only 26/400 interactions => less than 0. 03 Hz of recorded interactions CTP offline issues 13/11/07 16

SSM Event mode (not implemented) SSM records only trigger inputs for triggered events and event ID Rate estimate: • RND triger • 1 k. Hz DAQ rate = 1 ms/event • SSM readout time ~ 2 sec • Event info compressed in 3*32 bit words => 1 SSM ~ 300 k events = 300 sec • 100 k. Hz interaction rate => 1/400 = 0. 0025 interaction/event • => 2. 5 Hz rate of nonempty events CTP offline issues 13/11/07 17

Interaction signals logic Ø 2 interactions can be defined ØInteraction: any logical function of 4 L 0 inputs CTP Preliminary Design Review, http: //www. ep. ph. bham. ac. uk/user/pedja/alice/ CTP offline issues 13/11/07 18