1. CERN meeting report, and more … D. Breton
ETD/online session - Frascati Meeting
December 3rd 2009

2. Outcome of the CERN meeting (1)
The meeting took place beginning of November:
Attendance was 14 people (all sub-systems represented, unfortunately except DCH)
It was very pleasant and useful
We spent one day going through the ETD architecture once again to convince ourselves our choices were coherent with our goals
No showstopper was raised!
We started discussing about the L1 trigger
New proposals emerged there and since, and we will discuss them in this session.
We finalized the chapters for the white paper (see farther).
We also realized that costing couln’t be performed without realistic numbers for all the different type of fast links, especially the readout links
we requested all the sub-detectors to give us estimations for these numbers before the meeting.
we had fruitful exchanges about these points since, and we have now a first good (?) estimation of these numbers.
We defined « Online » and discussed choices for Online technologies
Could LHC frameworks & packages be directly applicable?
Network protocols for event building and data transport

3. Outcome of the CERN meeting (2)
Discussing about level 1 trigger, we realized that its granularity is of high importance for the quality of the selection
In BABAR, crystals were summed by 24 before being used in the trigger algorithm, grouped in phi strips
We think that a much higher (full?) granularity trigger is feasible with today’s technology (like on LHCb for instance).
To this end, we would need all the calorimeter information to go to the EMT
=> like on BABAR, the EMC front-end readout could be untriggered
=> but the latency buffer could then reside in the EMT itself, thus keeping the same overall architecture and a reasonable number of ROMs
Drawback of this solution is that the number of calorimeter readout links (~ 600) would be significantly higher than the total of all other sub-detectors (~140) => BABAR like!
Anyhow, we have to find a way to reduce the granularity
detecting overlap & pileup at trigger level, Bhabha veto, etc.
Once finalized, all chapters of the white paper got names in front of them and first contributions of all subsystems already arrived!
These exchanges are really helpful for system understanding at all levels
We refined the needs for the WBS cost estimates (see farther)

4. ETD/online chapters for white paper (1)
4.9 System level introduction(DB + UM + SL)
Global architecture (DB + UM + SL)
Overall trigger strategy (SL + UM)
Event Size Estimation and trigger rates (SL + UM)
Dead time and buffer queue depth (SL)
4.10 Front-End Electronics (DB)
SVT Electronics (MV)
DCH Electronics (GF)
PID Electronics (DB)
Forward PID option
Barrel PID
EMC Electronics (VB)
Forward calorimeter
Barrel calorimeter
Backward option
IFR Electronics (ACR)

5. ETD/online chapters for white paper (2)
4.11 Electronics, Trigger, DAQ (ETD) and Online (DB + UM + SL)
Introduction to ETD (DB)
ETD components (DB)
Fast Control and Timing System (DB + DC + CB)
Clock, Control & Data Links (AA + RG)
Common Front-End Electronics (JM)
Read Out Module (MB + UM)
Experiment Control System (DC + SL)
Low Level Hardware Trigger (DB + UM + SL)
Online (SL + GM)
Software infrastructure
Event building
High Level Software Trigger
Data logging
Event data quality monitoring and display
Other components
Conclusions (DB + UM + SL)
Cost estimations consideration

6. ETD elements for SuperB_costing
EDIA [mm] M&S [k€]
1.7.10
ETD (without Trigger)
FCTS
144
150
FCTS crates and supplies 2 30
Control and Distribution Module (2) 12 10
Fast Control and Timing Module (15) 84 60
Clock & Control Link Switch Module (7) 36 40
Throttle Switch Module (2)
CFEE
FCTS mezzanine (400 + protos) 48
140
Level 1 Buffer Control 6
Readout link control & serializer
Option 1: triggered EMC => 400 links
Option 2: untriggered EMC => 1000 links
320
ROM
ROM crates and supplies (5) 75
ROM crate controller (7) 50
ROM boards (40 ? 8 links/board)
200
ECS
SPECS masters (400 + protos) 3
100
SPECS Mezzanine (400 + protos) 80
SPECS links (400 cat5+ cables) 16
Clock & Control Links (400) 20
Readout links

7. What we expect(ed) from this workshop
We will try to refine our estimations for the number of links => done.
the front-end dedicated ETD session (Wednesday at 9:00) will focus on this point.
all the types of links will be visited, including FCTS and ECS
be aware that these elements are deeply related to the system topology
We will go on discussing about level 1 trigger fundamentals in the second session (Thursday at 11:15)
We will wonder what could be an optimum number of readout links at the input of a ROM
We will try to have the first ETD cost estimation ready for the TB => done
Overall ETD cost without L1 trigger is ~1M€ (if 400 links => EMC)
Further discussions on Online (many informal)
Applicability of existing LHC software and frameworks to SuperB Online
Discussion of event building networking protocols and transports
Run Control and Experiment Control System
Review of data logging rates