Physics and Detectors at the ILC

Fermilab P5 Meeting February 1, 2008 John Jaros

Particle Physics Needs a Linear Collider

• The physics of the terascale has captured the collective imagination of our field.

• We are at the threshold of discovering new phenomena and making fundamental advances in understanding mass, dark matter, and the properties of space and time.

• The LHC will introduce this chapter in particle physics, discover new phenomena, and guide our next steps.

• We will need the Linear Collider to elucidate and understand the the new physics.

Understanding the mechanism of EWSB requires the breadth of

measurements and the level of precision only the Linear Collider will provide.

Unique High Precision Higgs Branching Fraction Measurements

All branching ratios, good to ~few %, not 10’s of %. Precision needed to distinguish MSM and MSSM, 2HD, etc. Sensitivity to invisible decays, non-standard couplings to W,Z

Pinning Down Electroweak Symmetry Breaking

The Ideal Higgs Tag: e+e-ZHH

MSM?MSSM?2HD????

Dimuon Recoil Mass for Range of mH Coupling Mass?

Z0

• Critical Couplings DeterminedHiggs Top Yukawa Coupling

Higgs Self Coupling and the

Higgs Potential

Pinning Down Electroweak Symmetry Breaking

Possible at LHC?

Impossible at LHC

The most decisive test of EWSB

g/g ~ 10%

/ ~ 25%

Proving SUSY’s SUSY

SUSY may well be discovered at the LHC. Understanding if the new particles are in fact supersymmetric will depend on the precision measurements of masses, couplings, and mixing angles uniquely possible at the linear collider.

Precision Mass Measurements at ILC

Thresholdm~50MeV

Energy Spectrumm~100 MeV

m+ m0

Finding the SUSY Lagrangian and Fundamental SUSY Parameters

Precision mass measurements of charginos and neutralinos from the LC will allow the low energy SUSY parameters to be determined. With LHC input on squarks and gluinos, these can be evolved to high scales, to determine the fundamental SUSY parameters. High precision is the sine qua non.

Test Unification, Find MGUT, Explore SUSY Breaking

Understanding the Dark Matter

Precision LC mass and coupling measurements, in conjunction with measurements from LHC, will provide sharp predictions of the cosmological relic DM density, for various sparticle masses and mixings. These can be compared to the measured density.

Detailed knowledge of couplings will allow accurate estimation of DM-matter cross-sections, and calibrate indirect and direct DM searches.

LC Physics Challenges Detector DesignNot just a LEP/SLC or LHC Detector!

Jet Energy ResolutionE/E = 3-4%

Momentum Resolutionp/p2 = 5 x 10-5 [GeV-1]

Impact Parmeter Resolution b = 5 10/p sin3/2 [m]

Solid Angle Coverage = 4-

Present studies have quantified the benefits of excellent performance

Improving Ejet/ Ejet from 60% 30% is worth 40% more integrated luminosity(E/E = 30%/E is comparable to E/E = 3-4% for E~100 GeV)

• Improved Accuracy for Higgs mass from e+e-ZHqqbb

• Significance vs Insignificance for Higgs Self Coupling

Challenge for Calorimetry: Double Jet Energy Resolution

jet

jet

42 MeV

E0.3

E

hM

jet

jet

50 MeV

E0.6

E

hM

jet

jet

42 MeV

E0.3

E

hM

hhh

hhh

g

g

E/√E

30%

60%

Challenge for Tracking: Resolution X 5!

• Dimuon Recoil Higgs Mass

5

3

1.0 10

1.0 10

85 MeVh

a

b

M

5

3

8.0 10

1.0 10

273 MeVh

a

b

M

5

3

1.0 10

1.0 10

85 MeVh

a

b

M

Recoil Mass (GeV)

Recoil Mass(GeV)

2 sint

t t

p ba

p p

e e ZH

X

1

350

500

s GeV

L fb

Higgs Recoil Mass Measurement Improves as Tracker Momentum Resolution Improves

Characterize the Momentum Resolution with the parameter a:

An eightfold improvement in resolution is worth a factor of 10 in luminosity!ILC designs 5-10 x better than LEP!

ILC Environment Benign Compared to LHC…

LHC ILC• Event Rates

Inclusive 1 GHz (min bias) 1 kHz ( ->hadrons)

• Bunch Crossings 25ns (40 Mhz) 300ns (15kHz) DC 0.5% Duty Factor

• Triggering Level 1 & 2 40MHz -> 1kHz No Hardware Trigger Level 3 ~100 Hz Software ~100 Hz Software

• Radiation Field 1-100 MRad/Yr 10 kRad/Yr

• Occupancy Per bunch 23 min bias 0.3 ->hadrons 100 tracks 2 tracks

…but it poses its own challenges.

Example: Event pileup can overwhelm the VXD• Bunch train structure can swamp the inner layers of the VXD with

beamstrahlung induced pair backgrounds.

• To reduce occupancies to 5 mm-2, the effective readout speedmust be increased. New technologies are needed.

• Getting enough power in for faster readout, taking enough heat out, are real challenges for “massless” detectors!

ILC Detector R&D

• ILC physics and the ILC environment require detector R&D beyond that developed for LEP/SLC, the Tevatron, and LHC.

• An impressive world effort is underway on R&D for ILC detectors, including that organized by R&D Collaborations (TPC, SILC, CALICE, FCAL), the detector concepts, and individual institutions.

R&D Progress: Particle Flow Calorimetry and PFAs

• An excellent start! Still needConfirmationExperimental Proof (not so easy!)

How to Get Ejet/Ejet = 3-4% ?

Mark Thompson’s Pandora is a PFA Proof of Principle =EE

PFA’s measure jet energies by summing up charged track momenta, photon energies,and neutral hadron energy by differentiating their respective depositionsin the calorimeters. Highly segmented, imaging calorimetry is the key.

R&D Progress: Particle Flow Calorimetry

• Highly Segmented ECALs: Si/W and Scint/W

• RPCs and GEMs are being developed for DHCALRPC Slice Test Sliced 8 GeV Electron 30x30 cm2 GEM GEM MIP Signal

Calice Beam Test Results 12 mm2 Si Sensor with ASIC Readout

Crossed 1 x 4 cm Scint Stripsreadout with SiPMs

R&D Progress: Tracking

Module Design Tiling on C Fiber Barrels Barrel Deflections

LCTPC (R&D Collab) is developing high precision TPCs

Prototype Under Construction80 cm diameter/80 cm drift lengthTest GEMS and Micromega Readout7 Modules ~20x20cm each

SiD and SILC are developing low mass, high precision Si Trackers

• Among the regions, Europe has been the most successful in supporting detector R&D, with the US a rather distant second. Asia (mostly Japan) has recently increased support to roughly the level of the US.

ILC Detector R&D Status & Funding

Report from the WWS R&D (Damerell) Panel (2006)

Manpower Equipment

US lags badly Ditto, and gettingworse.

Are we losing an opportunity?

• In the US, support for detector R&D has been administered by LCDRD for the DOE and NSF, under the auspices of the ALCPG. Support has grown from 800k$/year in FY05 to 2.2M$/year for FY07, but is still well shy of support in Europe.Support in FY08 is uncertain or worse.

• The DOE and NSF conducted a joint review of US ILC detector R&D at Argonne in June 2007. Their report concludes:

“The committee was very pleased with the many advances made to date, despite the less than optimal funding available. The committee strongly encourages the funding agencies to increase the level of support substantially so as to position the US groups to be major players in the development of the ILC detectors.”

ILC Detector R&D Status & Funding

DoE/NSF ILC Detector review, Jun 19-20, 2007H.Weerts

Overview

Everything included as far as we know ILC Detector R&D Needs 100M$/5 years

Argonne (Weerts)

Integrated ILC Detector DesignsSiD LDC GLD

•Solenoid Designs B=5,4,3 Tesla•Si vs TPC Tracking•“Particle Flow” Calorimeters

4th

•Dual Solenoid•Compensating Cal•TPC Tracking

ILD

The Need for Integrated Designs

• Interaction Region Design needs intimate coordination between the machine and the detectors to reach ILC luminosity goals and control backgrounds. Realistic detector designs are a necessity.

• Detector subsystem designs must be integrated to optimize the balance of physics performance and cost.

• Conceptual engineering designs add the realism needed to assess and benchmark detector performance.

They force attention to real world problems: support structures, dead spaces, supplying power, removing heat, retrieving data, getting access for repair, and overall assembly. Smoke and mirrors not allowed.

• Realistic designs are needed to understand costs.

• ILC Baseline: 14 mrad crossing, 2 detectors push-pull, surface assembly• Must coordinate designs for the experimental hall, surface assembly, push-

pull, cryo, and vacuum with the Machine.

Machine-Detector Interface

Experimental Hall and Access ShaftsDoor opening Procedure, on the beam

Cut away view of IR Quads embedded in detector.

Present Designs can do the Physics

Momentum Resolution meets Tracking Efficiency ~ 100%

goal of p/p2 < 5 x 10-5 (GeV-1)

e.g. SiD

e.g. LDC

Jet Energy Resolution α E/E= α/E ~ 30 %/ E

e.g. GLDs=mZ

0.5%

Detector Costs• WWS Cost Panel (Breidenbach, Videau, Maki) evaluated costs

of GLD, LDC, and SiD• Costs include M&S and Manpower and Contingency in 2007

$’s. (Assumed 1 Yen=.00854$; 1 Euro=1.20$)• Mix of Manpower and M&S varies region by region by custom,

but totals are comparable.• Cost Drivers:

Solenoids and Calorimeters• Manpower:

1250-1550 person-years

Detector Cost: 460-560 M$

e.g.

• Oversaw Concept Launch SiD and LDC Concepts at ALCPG Vancouver 2004GLD Concept at ACFA Meeting Taipai 20044th Concept at ECFA Vienna 2005

• Called for Detector Outline Documents 2005

• Called for Detector Concept Report 2006Companion to GDE’s Reference Design Report

• Instituted Detector R&D Reviews 2007

• WWS Proposed Detector Roadmap 2007to ILCSC

ILCSC Called for Detector Letters of Intent andappointed Sakue Yamada Experimental Research Director. LOI’s will likely be due Spring 2009.

World Wide Study (WWS) Coordinates ILC Detector Development

Concepts DefinedTeams Assembled

Tracking, Cal, VXD

Case for Physics and Detectors

How Soon do we need LC Detectors?• Detector readiness must match machine readiness.

ILC plans to begin Technical Design Phase II in 2010 to prepare a proposal by 2012.

The detectors must start technical designs on the same timetable. Start 2010.

• Conceptual engineering and proof of principle R&D are needed prior to TDPII. ILC has been doing this for a decade or more.

ILC detector design and detector R&D lag badly. It’s time to catch up. Also needed for the LOI. Start NOW.

• It takes a Collaboration to design a detector and do detector R&D. This effort has begun with the ILC Concept Studies and R&D Collaborations, but has a long way to go. People can’t join this effort without support. Start NOW.

To be ready for this opportunity, LC Detector Design

and Development must be ramped up Now.

Conclusions

• Linear Collider Physics is compelling. LC is the right next step.• ILC Physics and Environment challenge the current state of the

art for detectors. • New detector technologies for ILC detectors are being

developed. There’s been impressive progress, but much more development is needed.

• US Funding for ILC detector R&D and detector design needs a significant boost to be ready when LHC results and ILC readiness can justify going forward.

• Integrated Detector Concepts are being developed which can do the physics, coordinate IR design, and evaluate the costs.

• We are starting on the next step, developing detector LOIs.