ATLAS Upgrade for SLHC by wuyunqing

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									 ATLAS Upgrade for SLHC
(with emphasis on electronics aspects)


           PH Faculty Meeting April 2008



             Philippe Farthouat, CERN
                              Presentation Overview


                Organisation of upgrade activities

                Expected changes in the detector

                Tracker upgrade

                Electronics

                CERN participation

                Summary



Ph. Farthouat                     PH Faculty Meeting April 2008   2
                              Presentation Overview


                Organisation of upgrade activities

                Expected changes in the detector

                Tracker upgrade

                Electronics

                CERN participation

                Summary



Ph. Farthouat                     PH Faculty Meeting April 2008   3
                                 Upgrade Organisation




                  Ref: https://edms.cern.ch/file/690177/1/Upgrade_Org_PO.doc
                Indico pages: http://indico.cern.ch/categoryDisplay.py?categId=350


Ph. Farthouat                        PH Faculty Meeting April 2008                   4
           Coordination of R&D activities

       Proposal made to the USG                            A number of proposals issued so far

       Established lightweight review procedure
       for approval
                                                           ATLAS welcome joint R&D activities with
                                                           other experiments (CMS)
       Circulation to collaboration board
                                                                Versatile link and GBT
            More groups joining?
                                                                130 nm or lower processes
                                                                Power distribution
       Second discussion in USG
            Sufficient resources?


       Decision about recommendation by USG

       Review procedure during the lifetime of
       the project
            Review office




Ph. Farthouat                         PH Faculty Meeting April 2008                                  5
                              Presentation Overview


                Organisation of upgrade activities

                Expected changes in the detector

                Tracker Upgrade

                Electronics

                CERN participation

                Summary



Ph. Farthouat                     PH Faculty Meeting April 2008   6
          Areas with significant changes
                Luminosity 1034                  1035 cm-2 s-1

Complete Inner detector
                           Parts of muon system



                                                          Interface to machine:
                                                               •Beam Pipe
                                                                •Shielding
                                                            •Possible machine
                                                              magnets inside




                                Forward calorimeter
Ph. Farthouat             PH Faculty Meeting April 2008                       7
                              Beam Pipe & Shielding
       Currently central part of ATLAS beampipe is Be, rest is
       Stainless Steel
            SS gives large backgrounds, especially to muon system


       SS gets activated          Access problems for maintenance
            Change to Al for ~2009
            Change to all Be for SLHC
            Be is expensive compared to SS, but cheap compared to muon
            chambers!
            It gives a big reduction in background in critical areas of muon
            system
                A factor 2 or better


       Shielding
            Already highly optimised, only small improvements possible


Ph. Farthouat                      PH Faculty Meeting April 2008               8
                                                                       Muon system
    Hit rate might be too high in some
    places

    Large uncertainty on the
    background rate
         Need to wait for first beam before
         knowing what the real rate is
         Current detector done with some
         safety factor on the simulated hit
         rate
         If at low end and a complete Be
         beam pipe in place, the precision
         chambers can remain


    Replacement or adaptation of the
    current readout electronics might be
    needed (see later)

    On going R&D
         Micromegas for both tracking and
         trigger (CERN involvement)
         Thin MDT
         TGC for both tracking and trigger

Ph. Farthouat                                 PH Faculty Meeting April 2008          9
                                            Calorimeters (1)


       EM calorimeter should work even with high pile up
            Adaptation of the digital filters in the back-end electronics
            Front-end electronics might require some changes


       Detecting elements of the Tile calorimeter do not
       need replacement
            However electronics very likely does (see later)




Ph. Farthouat                  PH Faculty Meeting April 2008                10
                                          Calorimeters (2)
                                                                HEC
                                                             electronics



       HEC front-end electronics in the                       FCAL
       cryostat. If a replacement is
       needed (because of radiation
       level) it will imply a major work

       Forward calorimeters need
       some adaptation because the
       liquid argon might boil…




Ph. Farthouat                PH Faculty Meeting April 2008                 11
                              Presentation Overview


                Organisation of upgrade activities

                Expected changes in the detector

                Tracker Upgrade

                Electronics

                CERN participation

                Summary



Ph. Farthouat                     PH Faculty Meeting April 2008   12
                                         Strawman layout




      All silicon: pixel, short strips (3.5 cm), long strips (9 cm)

      40M channels in Si strips (6M in the current detector)

      160M channels in Si pixel (80M in the current detector)
Ph. Farthouat                PH Faculty Meeting April 2008            13
                                                                             Radiation

         Radius in cm                   Dose in kGy
                5.05                      15800
            12.25                          2540
                29.9                       760
                51.4                       300
                43.9                       450
                108                         70

                        For 3000 fb-1




Ph. Farthouat                                PH Faculty Meeting April 2008               14
                                                                   Pixels
       Sensors for B-layer
            3D Si (Parker, Da Via et al)
            Thin silicon + 3D interconnects
            (Nisius et al)
            Gas over thin pixel (GOSSIP) (van
            de Graaf et al)
            Diamond pixels (Kagan et al)


       Front-end electronics IC
            Willing to have chips 4 times larger
            as current one and pixel size 2
            times smaller (50 x 250 µm)
            ~22000 channels/chip
            Development in 130nm CMOS
            technology for B-layer replacement
            CERN micro-electronics for
            technology access and CAE server

Ph. Farthouat                      PH Faculty Meeting April 2008            15
                Strips: Super-modules




                                                From Geneva University




Ph. Farthouat   PH Faculty Meeting April 2008                            16
                                                              Strips: Staves
                10cm detectors, each with 4 rows of chips on hybrids



                                            ~ 1 meter


                                    Carbon honeycomb or foam

                                                                                 Carbon fiber
       Bus cable
                                                                                 facing


                   Hybrids             Coolant tube structure          Readout IC’s

       Hybrids glued to detectors and this assembly glued to mechanical/cooling support


                                                  From Lawrence Berkeley National Lab.


Ph. Farthouat                       PH Faculty Meeting April 2008                           17
                                                                      Engineering
       Engineering organisation being put in place

       PO engineering and Design Office
            Shielding and machine interface


       ID System Engineering + Project Management (or engineering
       management and coordination)
            Centralized engineering team for integration:
                Integrated Design, System Engineering, all Structures and Interfaces, Assembly
                & Integration on surface, Installation, Services, Tooling
            Working groups on specific topics:
                Engineering / Integration
                     Engineering Layout, Structures, Services & PP, Interfaces, Installation …
                Services
                     Analysis and impact of existing Atlas Services on detector design


       Important CERN participation
            PO Project engineer: R. Vuillermet
            ID Project engineer: A. Cattinaccio

Ph. Farthouat                         PH Faculty Meeting April 2008                              18
                              Presentation Overview


                Organisation of upgrade activities

                Expected changes in the detector

                Tracker Upgrade

                Electronics

                CERN participation

                Summary



Ph. Farthouat                     PH Faculty Meeting April 2008   19
                           Electronics upgrade


       General concern for the electronics in the cavern

       Level-1 trigger

       Muon readout electronics

       Calorimeters readout electronics

       New readout electronics for the tracker



Ph. Farthouat            PH Faculty Meeting April 2008     20
                                                General concerns
       The electronics installed in the cavern will be affected by the higher
       level of radiation

       ATLAS rules defined safety factors for the radiation tolerance of the
       electronics
            Don’t know yet if we are on the safe side or not
            Major upgrades could be required if not
                Power supplies
                FE electronics of the calorimeters and muon chambers
                Control devices (ELMBs)
            Wait for the beam for final assessment


       A substantial fraction of the front-end electronics will be obsolete at
       the time of SLHC
            Could need a replacement in case of high level of failure


       R&D starting to be ready in case


Ph. Farthouat                        PH Faculty Meeting April 2008               21
                                                 Level-1 Trigger
       More complexe algorithms might be needed
            For instance, currently level-1 calorimeter only performs
            object counting
            So far no need for tracking in level-1


       Can both the latency and the L1A rate be
       maintained at their current values?
            2.5 µs and 75-100 kHz


       Very much linked to what will happen to readout
       systems of the calorimeters and muon chambers

       No real work started yet

Ph. Farthouat                  PH Faculty Meeting April 2008            22
                                       Muon readout




Ph. Farthouat   PH Faculty Meeting April 2008         23
                                 Calorimeters readout
       Additional radiation tests of the front-end electronics needed
       when LHC background known

       Both Lar and Tile calorimeters are looking at a new front-end
       system reading out everything at BC rate
            Large dynamic range (14-16 bits) ADC @ 40 MHz
            High data throughput
                Lar 1600 FE boards, each of them delivering 100 Gbits/s
            Backend electronics for readout and level-1 trigger
                High bandwidth backplane (ATCA,…)
            A bit brute force but allows very high flexibility for the trigger




Ph. Farthouat                     PH Faculty Meeting April 2008                  24
                      Strips readout architecture
     Cooling In                  Module #1            Module #2            Module #10

  TTC, Data &
  DCS fibers
                   Opto

                   SMC

   DCS env. IN     DCS
                   interlock
Cooling Out
                  SMC
                  Hybrid                                     Service bus
      PS cable


       Simulation data for the short strips show that a super-module
       will deliver ~3.2 Gbits/s of data
              SMC          GBT
              Optical readout link      Versatile link


       Front-end chip and Module controller

       Power distribution
Ph. Farthouat                        PH Faculty Meeting April 2008                      25
                                                         Front-end IC

       Very much interested in 130 nm technology or
       below
            Support from CERN for technology access highly
            appreciated
            Building blocks very welcome


       Also interested in the possibility of accessing SiGe
       option
            Possible power saving of the input stage of the FEIC by a
            factor three




Ph. Farthouat                 PH Faculty Meeting April 2008             26
                   Front-end IC development


       Binary readout as in current detector
            Called ABC-next


       First version being designed in 250nm technology
            To be used as test vehicle for the modules development
            Includes several option for readout speed
            Includes all the bit and pieces to be used with different
            powering schemes




Ph. Farthouat                  PH Faculty Meeting April 2008            27
                                                ABC-next




Ph. Farthouat   PH Faculty Meeting April 2008              28
                Next steps for the strips readout
       Finalise specifications based on the prototyping activity and choice
       of power scheme

       Move ABC-Next in 130nm CMOS technology

       Schedule not yet clear                                   Foot-prints for
                                                                   Module
                                                                  Controller
                                                                      &
                                                                Power devices




                                                                 ABC-next



Ph. Farthouat                   PH Faculty Meeting April 2008                     29
                        Development for Pixels


       Main activity is the design of the FEIC for the B-
       layer replacement
            To happen in 2012-2013


       130nm CMOS technology being used

       No CERN involvement in the design however needs
       CERN support for the access to the technology and
       for having an available CAE workstation at CERN
            Design done by several teams remotely located



Ph. Farthouat                PH Faculty Meeting April 2008   30
                                       Power Distribution
    All arguments given by Federico already
         The number of channels in the tracker is going to increase
         The new electronics technologies need less power but not less current
         What is a pain today will be an unsolvable problem


    A lot of R&D on-going
         ATLAS R&D proposal put forward about a year ago
         WP2 in the DG white paper
         ACES recommended to have common work on the subject
         Workpackage in EU FP7
         Common working group on power distribution

    Two alternatives looked at
         DC-DC converters either switched capacitors or air-core
         inductors (including WP2 presented this morning)
         Serial powering


Ph. Farthouat                    PH Faculty Meeting April 2008                   31
                                                 Serial Powering

       Currently used Parallel Powering:
                      constant         constant             constant    constant
   Powerlines         voltage          voltage              voltage     voltage
   Modules




       Idea of Serial Powering:
  TWO        constant
  powerlines current


   Modules
                10V       7.5V                 5V                2.5V       0V

Ph. Farthouat                    PH Faculty Meeting April 2008                     32
                                Serial Powering (cont.)

                                                                  on chip
    Basic principle:                                                                     LinReg
                                                                   ShuntReg
         Constant current through all
         modules
         Voltages generated on FE chips or
         modules by
                Shunt regulators
                Linear regulators
                                                                            FE chip


                  Shunt             FE                             FE        Linear
                  regulator         core                           core      regulator



                  Shunt             FE                             FE        Linear
                  regulator         core                           core      regulator

Ph. Farthouat                              PH Faculty Meeting April 2008                          33
                           Serial Powering (cont.)


       Attractive concept however not simple at system
       level
            Power optimisation difficult
                If several voltages are needed at the FE level (very likely for
                reducing digital power)
                Always max current going through the system
            Difficult to completly switch off a device
                Current still flowing through a non zero impedance
            Floating modules
                AC coupled or optics readout
                Issue with the grounding



Ph. Farthouat                    PH Faculty Meeting April 2008                    34
                         Summary of Developments
       Complete list of R&D available in EDMS
            Folder ATLAS upgrades
            https://edms.cern.ch/cedar/plsql/navigation.tree?cookie=7469794&p_top_id=1349898803&p_top_type=P&p_open_id=1278926912&p_open_type=P




       Electronics R&D in two main categories
            Generic studies of technologies
            Targetting a particular detector


       Common R&D with CMS are welcome
            Versatile link: formally submitted and reviewed by both
            experiments
            Common working group on power distribution




Ph. Farthouat                                             PH Faculty Meeting April 2008                                                           35
                                                                                Schedule
       Schedule unclear and we need a common date for the machine, ATLAS and
       CMS
            Not the case so far


       New tracker is the most demanding in terms of time

       Based on the experience of the current Si strips detector, and assuming the
       detector construction can be faster than what was achieved, we end up with
       the following schedule for the availability of the readout electronics (front-end
       IC, module controller, GBT and opto and power devices):
                   R&D                End Y-7
                   Specifications               End of Y-7
                   Final design                              Y-6 and Y-5
                   Production start                                        Beginning Y-4
                   Detector ready                                                          Beginning Y

       To be taken with care
            Two years faster than the current construction
                DMILL FE chip production slow
            Components on the super-module control hybrid might be available a bit later than
            FEIC and Module Controller

Ph. Farthouat                         PH Faculty Meeting April 2008                                      36
                              Presentation Overview


                Organisation of upgrade activities

                Expected changes in the detector

                Tracker Upgrade

                Electronics

                CERN participation

                Summary



Ph. Farthouat                     PH Faculty Meeting April 2008   37
                      CERN participation




Ph. Farthouat   PH Faculty Meeting April 2008   38
                              Presentation Overview


                Organisation of upgrade activities

                Expected changes in the detector

                Tracker Upgrade

                Electronics

                CERN participation

                Summary



Ph. Farthouat                     PH Faculty Meeting April 2008   39
                                                                        Summary
       ATLAS requires a substantial upgrade for SLHC
            Inner detector, Fcal, Part of the muon chambers

       The electronics part may need more upgrade because of
            Radiation level
            Obsolesence and aging of some parts
            Will know more after LHC start

       R&D activity started
            Detectors & Electronics

       Electronics R&D in power distribution, readout links and front-end
       designs
            Some common developments with CMS
            CERN « common projects » in line with needs
               Final and detailled specifications still to be defined


       CERN participation (and funding) not yet defined


Ph. Farthouat                          PH Faculty Meeting April 2008              40

								
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