Technological advances for the LHCb upgrade Marina Artuso Syracuse University

2 A few current LHCb physics highlights M. Artuso CPAD/Argonne D 0 -D 0 oscillations First evidence for B s ➝  most precise 1/10/20132 precise measurement of CPV in B s

3 more highlights 1/10/2013M. Artuso CPAD/Argonne3 BK*μμ & new physics in loops q 2 (GeV 2 ) search for Majorana ν

A new look at LHCb M. Artuso CPAD/Argonne Unique features of LHCb: particle detection in the forward region (down to beam-pipe) special particle identification capability in particular for hadrons due to RICH detector precise vertexing  1/10/20134

5 LHCb Upgrade: physics motivation tree diagram loop diagrams Working hypothesis: assume that tree level diagrams are dominated by SM and loop diagrams could contain NP, lots of opportunities to pursue evidence for new physics:  B s mixing observables  B(s),Λ b K*l + l -  CKM angle γ measured from tree mediated processes and loop mediated processes…  but also: Majorana neutrinos, lepton flavor violation in τ decays..

Upgrade goals  In order to reach the required sensitivity for these measurements we want a ≥ 10 increase in our data sample through:  Increase nominal luminosity (1-2x10 33 cm -2 s -1 )  Increase efficiency on beauty and charm hadronic final states trigger ( ≥ 2)  Schedule:  R&D phase in progress and should end in 2014  Installation during long shutdown ~2018. M. Artuso CPAD/Argonne1/10/20136

7 Expected sensitivity to key channels M. Artuso CPAD/Argonne1/10/20137 arXiv:1208:3355

8 Running at L ~ 2x10 33 cm -2 s -1 M. Artuso CPAD/Argonne LHCb Upgrade Event Environment:  L  L ~ 2x10 33 cm -2 s -1 with 40 MHZ beam crossing frequency  ~26 MHz rate for crossings with ≥ 1 interaction  μ ~ ∙ /10/20138

M. Artuso CPAD/Argonne 2011 First Trigger Level: Hardware Muon/ECAL/HCAL 1.1 MHz readout 2011 First Trigger Level: Hardware Muon/ECAL/HCAL 1.1 MHz readout The hadronic channel yields saturate at high luminosity LHCb trigger evolution 1/10/20139

10 The LHCb upgrade M. Artuso CPAD/Argonne New VELO telescope (pixel or strip) No Aerogel/new photon detector for RICH New Si strip TT New IT (Si or Scintilla ting fiber) Remove M1, SPD/PS New front-end electronics and data acquisition network 1/10/201310

M. Artuso CPAD/Argonne Data acquisition strategy 1/10/201311

12 The Tell40 DAQ board M. Artuso CPAD/Argonne Input 96 GBT links Output 10 GbE links Input 96 GBT links Output 10 GbE links The GBT is a radiation tolerant chip that can be used to implement multipurpose high speed ( Gb/s user bandwidth) bidirectional optical links for high-energy physics experiments. 1/10/201312

13 changes to the tracking system 1/10/2013M. Artuso CPAD/Argonne13

Tracking  At L=2x10 33 cm -2 s -1 the event topology is more complex:  More primary vertices  Increased track multiplicity  Bunch-to-bunch spillover  Detector occupancy  The challenge:  Suppress ghost tracks (incorrect combination of track segments)  low processing time in HLT (~25 ms)  Maintain high track efficiency (~90% when p≥5GeV)  Excellent momentum, time, and vertex resolution M. Artuso CPAD/Argonne1/10/201314

VELO Upgrade - pixel option  4 sensors per side  One sensor, 3 chips  Each chip has 256x256 pixels  55 x 55  m 2 1/10/2013M. Artuso CPAD/Argonne15 ~15mm ASIC ~43mm Sensor tile : Beam Distance to the closest chip ≤7 mm. Distance to the closest chip ≤7 mm. Sensor 200um ASIC150um Substrate 400um Cooling channel Bot Sensor 200um ASIC150um Connector cross section Strip option studied as well

The environment 1/10/2013M. Artuso CPAD/Argonne16 Radiation:  order of 370 Mrad in 10 year lifetime  and about MeV n eq cm -2 s -1  Highly non-uniform occupancy per chip  Average # particles / chip / bx (25 ns)  Hottest chip sees 5.8*40 = ~230 Mtrack/s  Each track has 2.2 hits on average -> ~ 500 Mhits/s per chip Other:  To be operated in vacuum Cooling and outgassing challenge See Jan Buytaert’s talk on micro-channel cooling on Thursday afternoon  Moveable structure Constraints on the cabling

17 The material issue: RF foil M. Artuso CPAD/Argonne1/10/201317

18 The material issue: low mass cooling 1/10/2013M. Artuso CPAD/Argonne18 microchannel CO 2

19 The TT intermediate tracker M. Artuso WIT2012, May  4-fold purpose:  Selection of high momentum tracks in an early stage of the online track trigger.  Reconstruct trajectories of long-lived tracks decaying outside the VELO  Track segment to ease pattern recognition and ease matching between VELO and T station track segments  Reconstruction of momentum of slow particles To achieve this:  use 4-6 planes of Si strip sensors with shorter strip lengths (2.5 to 10 cm)  Increase acceptance at high  To achieve this:  use 4-6 planes of Si strip sensors with shorter strip lengths (2.5 to 10 cm)  Increase acceptance at high 

T Station Upgrade M. Artuso CPAD/Argonne Two options for IT replacement:  Silicon strips (current technology, but lower mass and larger coverage)  250 μm Scintillating Fiber Tracker read out by SiPM  A single Scintillating Fiber technology implementation for the the whole T station plane is being studied IT-fiber detector layout: 1/10/ Readout by SiPM with readout cells 0.25 x 1.32 mm R&D ongoing to validate this option: radiation hardness of SiPM, need dedicated shielding, low temperature… Need to keep the fibre straight to ~50 µm and flat to ~200 µm over 2.5 m!

21 Particle identification M. Artuso CPAD/Argonne No major changes envisaged for calorimeter and muon system Hadron ID (RICH): Immediate changes: replace HPD with maPMT For a later date: TORCH: Provide low momentum PID (important for flavor tagging) measure the time of flight of Cherenkov photons produced in 1 cm thick 6x5 m 2 plate Located after T stations resolution in arrival time per p.e. needed ~70 ps

Conclusions  The LHCb upgraded detector is poised to pursue a vast array of very exciting physics topics with great discovery potential.  The trigger/data acquisition concept is based on shipping the zero suppressed data from the front end to an event builder farm where a complex and flexible HLT trigger exploiting the tracking information to reconstruct the event topology can be implemented.  The tracking system for the upgrade is designed to sustain higher data rates and radiation, as well as mass minimization in mechanical support and cooling.  We are looking forward to this exciting chapter of the experiment. M. Artuso CPAD/Argonne1/10/201322

M. Artuso CPAD/Argonne The End 1/10/201323

24 The occupancy challenge M. Artuso CPAD/Argonne Front end ASIC must digitize, zero suppress and transmit event data at 40 MHz Occupancy minuscule compared to other pixel devices, but huge data rates 1 ASIC has to transmit Gbit/s 1/10/201324

25 Readout Scheme M. Artuso CPAD/Argonne1/10/201325

26 Generic sub-detector readout and control M. Artuso CPAD/Argonne Common electronics 1/10/201326

Staging 40 MHz readout LLT as “throttle”:  Hadronic final states such as  benefit the most  Can see the effect of current trigger at 1 MHz M. Artuso CPAD/Argonne   K   L =10 33 cm -2 s -1 1/10/201327