SiD

A Linear Collider Detector

SLAC Users Organization Annual Meeting September 17, 2009

John Jaros

LC Physics Case is Compelling as EverWe expect LHC to discover New Physics at the Terascale

Understanding the new discoveries will require the Linear Collider• Detailed and precise measurements are needed to understand the

mechanism of Electroweak Symmetry Breaking• Precision measurements of dark matter properties are required

to infer its role in cosmology• Precision measurements of SM processes will open windows

to higher energy scales

LoIs Have Advanced the LC Detector Case“Letters of Intent” were submitted for international review and

“validation” in March of 2009 by ILD, SiD, and 4th (detector concept groups)

• Register intent to develop and detail a design for an ILC detector, and to proceed with preparing a Technical Report in 2012 to accompany the ILC’s Technical Design for the machine

• Provide a full detector description, sub-detector status, and a discussion of machine-detector integration.

• Evaluate the performance of the proposed detector with full Monte Carlo simulation, including beam backgrounds

Both ILD and SiD have been “Validated” by the International Detector Advisory Group.

SiD Letter of Intent was submitted 31 March, 2009 and signed by 244 physicists and engineers, representing 77 institutions, worldwide

The SiD LoI and other information about SiD can be found on the SiD webpage:http://silicondetector.org/display/SiD/home

The LoI’s have accelerated progressin answering key questions

• Are the proposed designs feasible? Are they within reach technologically?

• Do the proposed designs make engineering sense? Are they buildable, supportable, alignable, and calibratable?Are machine and detector believably integrated?

• Can realistic detectors, in full simulation and accounting forbeam backgrounds, do justice to ILC physics?

• Jet energy resolution goal is E/E=3-4% to distinguish hadronic decays of W’s and Z’s, identify Higgs and Top, and measure W/Z energies precisely

• Excellent charged particle momentum resolution pt/pt2 ≤ 5 x 10-5 GeV-1

to identify Higgs in recoil and measure SUSY endpoint spectra precisely

• VX Tracker with impact parameter resolution = 5 10/psin3/2 [m]to measure Higgs Branching Fractions to bottom, charm, and gluons, and tag quark charge.

• Full solid angle coverage to capture multi-jet final states; hermetic calorimetry to utilize missing energy signals from SUSY

• Tolerance for intense backgrounds from beamstrahlung, gamma-gamma backgrounds, and sporadic showers from errant beams

Precision LC Physics Requires High Performance Detectors

Silicon Detector

VTX 5 layer Si pixels Barrel and Endcap

TRK 5 layer Si strip Barrel and Endcap

ECAL 30 layers Si/W 3.5 x 3.5 mm2 pixels

HCAL 40 layers RPC/Fe 4.5 1 x 1 cm2 cells

MAGNET 5T SC Solenoid

MUON 11x 20cm Fe layers RPC ~ 2 cm

Technical Feasibility: Low Mass Tracker

Sensor Modules tile lightweight CF+Rohrcell cylinders Prototype Hamamatsu Sensoris read out by two KPiX ASICS(2 x 1024 channels)

Power pulsing permits air cooling,minimizing tracker mass. X/Xo ~ 10-15 %

Si Provides Superb Momentum Resolution

p/p = 0.2%

Technical Feasibility: EcalConceptual engineering design for Si/W Ecal

Hamamatsu Sensors and KPiX prototypes are under test

Detector Gap

Hex Sensor (1024 pixels)

Technical Feasibility: HCalGlass RPC (Argonne) is a viable hcal detector candidate

RPC Slice Test Results

Multiplicity vs Efficiency Response to ElectronsNumber of Hits for Different Energies

Digital Hcal countsnumber of 1 x 1 cm2

cells hit in shower

Technical Feasibility: MDIIntegrate final quads Cryogenics, beamline connections, self-shielding

Push-Pull

All in all, there has been a good start on SiD’s conceptual engineering.

• SLIC provides full detector simulation in Geant4 - runtime detector description in XML - stdhep input

• org.lcsim reconstruction/analysis suite - XML detector geometry description - Java-based reconstruction & analysis framework - LCIO standard output

• SLAC Sim/Recon is playing a critical role in new detector development - Generation, Detector Simulation, Reconstruction critical for LoI studies - 100 M event MC samples for physics benchmarking and detector performance studies (thanks BaBar!)

Simulating SiD’s Performance withSLAC’s LC Simulation/Reconstruction Toolkit

Perfect for System Development easy to define detectors easy to use works on multiple OS

Being used for ATLAS studiesand Test Beam Analysis

Simulations use Full Monte CarloNewly Created Pattern Recognition codes• SiD Iowa Particle Flow Algorithm demonstrates desired jet

energy resolution in full SiD Monte Carlo

• SiD Pattern Recognition/Tracking is fully efficient with superb momentum resolution in full Monte Carlo

ZZ Events at 500 GeVE/E = 4.0 % (rms 90)

Vs cos Vs pT

p/p vs p

Backgrounds Fully Simulated• Salt and Pepper Backgrounds arise as 10 TeV of e+e- pairs hit the

beamcal, showering the detector with MeV photons ee,,, hads comprise a physics background for all events

• Tracker performance near perfect in full MC physics + all backgrounds

150 Bunches (TPC) 1 Bunch (Si Tracker)

Physics Benchmarking StudiesCan LC Detectors really do the Physics?

• LoI Benchmark Reactions

• Ground Rules: Full MC; Actual Reconstruction Code; Include backgrounds

Higgs Recoil Analysis

e+e -H +-H

MH = 0.040 GeV ZH/ZH = 0.031 for 250 fb-1

No Impact fromBackgrounds

Chargino and Neutralino Masses

• Reconstructed Boson Masses: PFA discriminates W’s and Z’s

• Reconstructed Boson Energies. The endpoints measure masses.

Pure Pure 0

EW EZ m() = 0.45 GeVm(2

0) = 0.49 GeVm(1

0) = 0.16GeV + SMBKG

What’s Next?

• The LoI’s have established a new level of confidence in detector feasibility and projected physics performance for LC detectors

• What remains is the homework for the Detector Technical Reports in 2012:

- Demonstrate proofs of principle for all critical components

- Complete a realistic conceptual engineering description for the detector and machine-detector integration

- Develop a correspondingly realistic simulation for the detector

- Benchmark the physics performance of the detector in full simulation, including backgrounds, at 500 GeV and 1 TeV.

SiD needs help in all these areas, significantly more support, and new collaborators to accomplish these goals.

SLAC’s SiD Group

SiD Department Marty Breidenbach John Jaros

SiD Sim/Recon Norman Graf Ron Cassell Tony Johnson Jeremy McCormick

SiD Ecal Electronics Gunther Haller Dieter Freytag

Ryan HerbstSiD Tracking Tim Nelson

Rich PartridgeSiD MDI/Polarization Tom Markiewicz Ken Moffeit Takashi MaruyamaSiD Benchmarking Tim BarklowSiD Vertex Detector Su Dong

Contact Us!

SLAC USERS working on SiDU Colorado S. Wagner

U. NauenbergUC Davis M. Tripathi R. Lander U Iowa M. Charles

U. MallikMississippi L. Cremaldi

J. Reidy H. Zhao

MIT R. Cowan P. Fisher D. Yamamoto

U Oregon J. Brau R. Frey N. Sinev D. Strom

UCSC B. SchummWisconsin H. Band

Plus Growing International Participation: Annecy KEK Tokyo RAL Oxford