the electronics system of the alfa forward detector for luminosity measurements in atlas
DESCRIPTION
The Electronics System of the ALFA Forward Detector for Luminosity Measurements in ATLAS. Presenter : F . Anghinolfi B. Allongue 1 , J. Alozy 1 , G. Blanchot 1 , S. Franz 1 , W . Iwanski 1 , V. Lorentzen 2 , B. Lundberg 3 , S . Jakobsen 4 , K. Korcyl 5. - PowerPoint PPT PresentationTRANSCRIPT
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27/9/2011 TWEPP 2011 F. Anghinolfi CERN/PH/ESE 1
The Electronics System of the ALFA Forward Detector for
Luminosity Measurements in ATLAS
Presenter : F. Anghinolfi
B. Allongue1, J. Alozy1, G. Blanchot1, S. Franz1, W. Iwanski1, V. Lorentzen2 , B. Lundberg3, S. Jakobsen4, K.
Korcyl5
1CERN, 2HIST Trondheim , 3Lund University, 3NPI Copenhagen, 5INP PAN, Cracow
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27/9/2011 TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2
ALFA
Mechanics Electronics Detector
LHC
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27/9/2011 TWEPP 2011 F. Anghinolfi CERN/PH/ESE 3
ALFA : Absolute Luminosity Measurement
Each “RP” is a 20x20mm mini tracker made of 10 planes of staggered scintillating fibers in U and V directions, plus 2 scintillating plates covering the tracking area for producing trigger signals
Two small trackers symmetrically placed around the proton beam, the detector to beam distance can be as low as 1.5mm. Measure the elastic beam scattering at very low distance of the beam.
One “UP”
One “DOWN”UP
DOWN
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 4
ALFA R/O electronics
27/9/2011
Up Down
Up Down
Up Down
Up Down
RR13 alcove
RR17 alcove
USA15 counting
room
250m + through tunnel & galleries 250m + through tunnel & galleries
In alcove : LV power supplies
In alcove : LV power supplies
USA15 :HV unitsDCS control & monitorRODLV PFC and controlCTP
Each station (A, B):2 pots (up and down)2 readout systems (PMF + Motherboard)1 (main) Patch Box2 HV dispatchers
For A&B :1 optolink dispatcher
Each station (A, B):2 pots (up and down)2 readout systems (PMF + Motherboard)1 (main) Patch Box2 HV dispatchers
For A&B :1 optolink dispatcher
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE
ALFA R/O electronics
27/9/2011 5
RR13/17 alcove
USA15 counting
room
In alcove : LV power supplies USA15 :
HV unitsDCS control & monitorRODLV PFC and controlCTP
LV voltages
380V DC
Maraton Control
Connections Source/dest.LV Power Local alcoves
TTC USA15, fiber
Data (Read) USA15, fiber
Control & Monitoring
USA15, CAN bus
HV USA15, electrical
Patch Box B
Down B
Up B
Down A
Up A
Patch Box A
HV Patch Opto Patch
Control & Monitoring (DCS)
TTC, Data
local tunnel
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE
ALFA R/O electronics
27/9/2011 6
USA15 counting
room
USA15 :HV unitsDCS control & monitorRODLV PFC and controlCTP
Connections Source/dest.Main Trigger Air core, USA15
(CTP)
OVLP Trigger USA15, electrical
Down B
Up B
Down A
Up A
local tunnel
Main Trigger
Main Trigger
2 overlap Trigger
2 overlap Trigger
2 overlap Trigger
2 overlap Trigger
Main Trigger
Main Trigger
TRIGGER SIGNALS
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE
ALFA R/O electronics
27/9/2011 7
PMT readout
MAROC ALFA-R Motherboard Tunnel USA15
L1 Buffer & serializer 40Mb/s
Serializer 1.2Gb/s
TrackData Flow
PMT readout Line DriversTrigger Flow
PMT readout Registers SPI interfaceConfiguration Flow
ROD
DCS
CTP, Trigger Logic
On Each Pot
FE structure : PMF
MAROC ALFA-T Trigger Mez. Tunnel USA15
“Lucid” PMF
Mask/AND
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ALFA R/O electronics
27/9/2011 8TWEPP 2011 F. Anghinolfi CERN/PH/ESE
PMT readout L1 Buffer & serializer 40Mb/s
Serializer 1.2Gb/sData Flow
A DTrigger Latency
Buffer
Ser
ializ
er
FE structure : PMF (23x)
Fast ShaperPer channel adjustable Gain Variable Threshold
MAROC2 ASIC
Trigger LatencyBuffer & Ser.MAROC2 configuration
ALFA-R FPGA
Amplifier Discriminator
Ser
ializ
er
Buffer23x
Buffer & Ser.Data FormatALFA-R Data Flow controlSPI interface
ALFA-M FPGA
64 channels
On MotherboardKapton cable
Tracking Data flow on each detector
To USA15
From PMT
Trigger
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 9
ALFA R/O electronics
• Aimed for compact, removable electronics• Minimal cabling constraints (from USA to RP)• FE Electronics centered around the MAROC2
ASIC developed by LAL/Orsay for MA-PMT readout systems
• Partial Radiation Hardness (Power supplies and regulation, ELMB, TTC GOL QPLL etc …)
27/9/2011
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 10
Detector and Front-End Parts
27/9/2011
3 stacked PCB mounted on the MAPAMT pins : HV distribution, signal distribution, active layer (pictures on the right)
MAROC side
ALFAR FPGA side
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27/9/2011 TWEPP 2011 F. Anghinolfi CERN/PH/ESE 11
Detector View
● 10 tracking modules, 3 overlaps and 2 triggers
● 1460 fibres and trigger lightguide bundles to optical connectors
● 2 LED and 2 PT100 sensor
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 12
ALFA Electronics on each pot
Detector
23 PMFs :5 rows1460 readout channels
Connections Source/dest.LV Power Local alcoves
TTC USA15, fiber
Data (Read) USA15, fiber
Control & Monitoring USA15, CAN bus
Triggers USA15, electrical
“Motherboard”
Targets :
Collects and serialize data from 23 PMFs
Long distance links to USA15 (no repeaters)
Independent control and monitor through ELMB
Removed from tunnel when not in use27/9/2011
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Functions distributed in the front-end electronics
27/9/2011 TWEPP 2011 F. Anghinolfi CERN/PH/ESE 13
ALFA_T2 Trigger Main +2 Trigger OVLP
ALFA_M
DataReq
L1A
ALFA_R
DataReady
DataOut+BCR+ECR
DataReady
DataOut+BCR+ECR
x1
x23
64 Tracks
On Mezzanine
On PMFDataReq
L1A
L1A
ELMB
On Motherboard
ALFA_T functions : Local Trigger PatternMain Trigger ChargeTrigger rate counterLED pulser
ALFA_R functions : Tracking PatternTrack Detector Charge measurement *
ALFA_M functions : SYNC & SEND DATATrack Detector Charge measurement *SPI interface (PVSS control)
* : Special run, very low trigger rate, standalone ALFA, special data format
ELMB/PVSS functions : MAROC configurationChannel maskingLED Pulse parametersTrigger pattern configurationLatency adjustmentMonitoring
To GOL
SPI
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 14
Motherboard Main Functionalities• 23 PMFs for measurement with 64 pixels >> 64 bits of data for each PMF• PMF passes its raw data serially to the ALFA-M controller• ALFA M collects raw data with the same L1ID and then transmit it through a GOL link to the ROD
DATA ROD(USA15)
TTCModule(USA15)
TTC CAN BUS
5 PMFs
5 PMFs
4 PMFs
4 PMFs
5 PMFs
MB1 connector
MB2 connector
MB3 connector
MB4 connector
MB5 connector
CAN BUS connector
GOL connector
ALFA MFPGA
Motherboard
Serial links
ELMBTTC rx
TTC Connector
GOL chip
QPLL
SPI
POWER• System
clocked at 40MHz, few KHz L1 rate
• 11A, 5V (with 23 PMFs)
27/9/2011
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 1527/9/2011
TTCR
FPGAALTERA
EP3C40F780C6N
+7V (MB)+5V (MB)
QPLL (40MHz LVDS)
SPI Bus (from MB)
Regulators
Trigger Pattern (LVDS @ 40 MHz)
Trigger Data (LVDS @ 40 MHz)
Spare IO (8)
Spare LVDS (3)
Interface toTrigger
Mezzanine
Motherboard Details
References Temp probe
PMF
confi
g (S
PI)
PMFs Row
ADC
Anal
og
Dat
aRea
dy/O
ut
PMF
confi
g (S
PI)
PMFs Row
ADC
Anal
og
Dat
aRea
dy/O
ut
PMF
confi
g (S
PI)
PMFs Row
ADC
Anal
og
Dat
aRea
dy/O
ut
PMF
confi
g (S
PI)
PMFs Row
ADC
Anal
og
Dat
aRea
dy/O
utTTCRx
PMF
confi
g (S
PI)
PMFs Row
ADC
Anal
og
Dat
aRea
dy/O
ut
SPIDCS CAN
busELMB
Opt
o Io
latio
n
Ports
Optolink
VCSELData
GOL
Monitors
Pin Diode
Clock distribution
Optolink
QPLL 50MHz
Capability of track charge measurement(to measure charge collection degradation)
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 16
Trigger Mezzanine Functionalities• 4 “LUCID” PMFs for Trigger charge measurement and time detection• Triggers Outputs are programmable combination of Trigger inputs (2 main, 2 OVLP)• Two programmable pulse generators for in-detector test LEDs
DATA
POWER
Main1 Trigger
OVLP1 Trigger
Main2 Trigger
OVLP2 Trigger
Main Trigger PMF
OVLP Trigger PMF
Main Trigger PMF
OVLP Trigger PMF
Mezzanine
DriversSPI
MB connector
MB connector
Test LEDs (2)Main Trigger (1) OVLP Trigger (2)
MotherBoard
ALFA TFPGA
27/9/2011
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17TWEPP 2011 F. Anghinolfi CERN/PH/ESE27/9/2011
PMF LUCID 1 PMF LUCID 2
Interface Interface
Trig1,2 Trig3,4
ADC ADC
Anal
og
Anal
og
FPGAALTERA EP3C25F256CN
+7V (MB)+5V (MB)
QPLL (40MHz LVDS)
SPI Bus (from MB)
PMFConfig
PMF Config
DACLED Driver
LED Pulse LED1
LED2
Main Trigger
Overlap 1
Overlap 2
Air-core
OVL1
OVL2
NIM Drivers
Regulators
Trigger Pattern (LVDS @ 40 MHz)
Trigger Data (LVDS @ 40 MHz)
Spare IO (8)
Spare LVDS (3)
Interface to “LUCID” PMFs (LUND Devlpt.)Two PMFs plugged on the mezzanine;Two interface holding lemo inputs and attenuators on top of LUCID PMFs.
Interface to MB:Two connectors to bring power and to interface with ALFA-R: clock, config bus, trigger pattern, qdc outputs;Spare single ended and LVDS IOs.
Trigger Mezzanine DetailsCapability of trigger charge measurement : the trigger charge is measured and transmitted at every L1, together with tracking data and the trigger pattern
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27/9/2011 TWEPP 2011 F. Anghinolfi CERN/PH/ESE 18
• The Trigger mezzanine contains the circuits for :
LED Pulsers (2 LEDs installed in each pot for light excitation)
Trigger Logic (trigger signal can be a combination of the 4 trigger sources)
Main Trigger charge measurements
Triggers signal processed by the MAROC2 chip, mounted on the LUCID PMF
MB
Mezzanine
Lucid PMFWith Maroc
TriggersInputs
TriggersInputs
Adaptor
= LEMO connector
Main TriggerOverlap 1Overlap 2LED Pulse 1LED Pulse 2
Connectors
Trigger Mezzanine Details (2)
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ALFA “Motherboard” implementation
27/9/2011 TWEPP 2011 F. Anghinolfi CERN/PH/ESE 19
FPGA
ELMB
TriggerMezzanine
Temp Connector
ELMBConn.1
ELMBConn.2
Power Conn. TTC Fiber
GOLlink
ELMB : control and monitoring
Trigger Mezzanine
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ALFA Electronics implementation
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Partial view of the kaptons cabling, PMF are located inside,HV connectors on the right trigger signals on the left. White wires are the internal HV lines.
PMT, PMF and kaptons are enclosed in a dark box, the motherboard carrying other elements (ELMB, trigger mezzanine) is vertical on the edge
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2127/9/2011
Electronics commissionning
No light HV ON Light ~1p.e.HV 950V
Electronics commissioning was performed on the 8 systems just before installation and repeated after installation
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2227/9/2011
Electronics commissioning
Electrical test stand : one charge signal injected in one channel. The method was used to verify the channel mapping for DAQ reconstruction
LED test stand : one long distance LED (about 1m and light diffuser) is used to illuminate all channels. In this plot one PMF “row” is not operational, as well as a 3 other PMTs (HV off)
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2327/9/2011
Electronics commissioning
Internal LED pulser : light is passing through leaks in the optical connectors. More light at the center (where the LED is located). Test on one RP system after its installation in the tunnel.
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2427/9/2011
Electronics commissioning
Internal LED pulser : ON LINE MONITORING
Top left figure : on-line hits display
Top right figure : Number of hits per layer
Left : number of layer with hits
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2527/9/2011
Electronics commissioning
TOP : first tracks reconstruction, after installation.LHC normal run, ALFA in “garage” mode
Top right : Accumulated hits display on one detector (20 layers), LHC normal run, ALFA in garage mode
Bottom right figure : Reconstructed tracks projection. Double hits reconstruction show up reco outside of the detector area
Plots are Courtesy of ALFA soft team
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2627/9/2011
Electronics commissioning
Detector layer hits during LHC runs,20 layers in one RP, garage position
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2727/9/2011
Electronics commissioning
Trigger signals Charge measurements (internal LED) for the 8 pots
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2827/9/2011
Installation in LHC Tunnel
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 2927/9/2011
ALFA Electronics
• All 8 pots fully operational right after installation in January 2011
• The track signals charge measurement will be installed during 2011 winter shut down (firmware update)
• Connections to the ATLAS CTP and trigger signals timing adjustment performed after installation (commissioning still going on, insertion to the Level 1 ATLAS trigger system)
• Some specific LHC runs with low beta angle are used to commission the detector for physics (in coordination with TOTEM)
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ALFA ELECTRONICS
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SPARES
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Data readout : modified modes
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ALFAT
ALFAR
ALFAT
Event
Maroc Delay Pipelined track hit
ALFAR
ALFAT
ALFAT
L1
Pipelined TRIG hit
Pipelined TRIG_ADC hit
DataReq
Maroc + combinatorialDelay
Maroc + MUX + ADC Delay
Buffer
Buffer
Buffer
Track hit
TRIG hit
TRIG hit
BC tag, L1 tag
ALFAR
ALFAT
Problem here : the interval is made of 3 successive functions :1 – MAROC (50ns)2 – Scan channels (up to 5 = 5us ?)3 - ADC (500ns) It may exceed the latency time (?)
Warning . TheMUX ADC delay is different for the two QDC channels !
SER.
SER.
To MB
To MB
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Trigger QDC readout : modified modes
32
Trigger Counters12 significant bits 16 significant bitsBCID/L1ID
Trigger Pattern16 significant bits
64 bits (4 groups of 16 bits)
T.Count number of bits :
Hypothesis : for an average count per ms the maximum theoritical count is 40K. 16 bits is 65K. There is no minimum count limit.A realistic number would be 200 (5Khz hit rate, no background)
Trigger Charge 2Trigger Charge 112 significant bits
27/9/2011 TWEPP 2011 F. Anghinolfi CERN/PH/ESE
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TWEPP 2011 F. Anghinolfi CERN/PH/ESE 3327/9/2011
Electronics commissionning
No lightHV ON
Light ~1p.e.HV 950V
Light ~1p.e.HV 900V