Research for the International Linear Collider Professor Andy White October 2005

What do we know now (2005)?

What don’t we know now (2005)! - Why particles have mass - Whether all four forces merge at high energies - If we live in more than Four dimensions - What is the Dark Matter - What is the Dark Energy - …?

Contributions to the Higgs mass Produces an infinite result due to summation over momenta of particles in the circular loop. Is there a Hiigs field that gives mass to particles?

A possible cure? …add a contribution that cancels the bad contributions: But this requires new particles !

A better merging if SUSY is included!

Many of our present questions should be answered at the Large Hadron Collider

UTA is a member of the ATLAS Collaboration

…but ATLAS discoveries will need have detailed follow up and verification before we know what the real nature of the new physics is!

ILC - Accelerator 5 bunch trains/s 337 ns between collisions Luminosity : 3.4x10 34 cm -2 s -1 (6000xLEP) Physics rates e+e- qq 330/hr e+e- W+W- 930/hr e+e- tt 70/hr e+e- HX 17/hr Background rates e+e- qq 0.1 /Bunch Train e+e-  X 200 /Bunch Train ~ 90 – 1000 GeV Superconducting RF Technology

ZHH Emphasize precision measurements – in a difficult environment – many multijet final states. σ(e+e-gZHH) = 0.3 fb ILC - Physics ?? Optimizing the physics for 1 or 2 detectors??

SiD Detector Solenoid

ILC – Detector Requirements - Good momentum resolution e.g. for ZH with Z -> µµ - Vertex resolution for flavor tagging c/b - Good jet energy energy and jet-jet mass resolution - Good coverage for missing energy - Good separation of charged/photons/neutral clusters -> Good pattern recognition, two track separation

Physics examples driving calorimeter design Higgs production e.g. e + e - -> Z h separate from WW, ZZ (in all jet modes) Higgs couplings e.g. - g tth from e + e - -> tth -> WWbbbb -> qqqqbbbb ! - g hhh from e + e - -> Zhh Higgs branching ratios h -> bb, WW *, cc, gg,  Strong WW scattering: separation of e + e - -> WW -> qqqq e + e - -> ZZ -> qqqq and e + e - -> tt Missing mass peak or bbar jets

Physics examples driving calorimeter design -All of these critical physics studies demand:  Efficient jet separation and reconstruction  Excellent jet energy resolution  Excellent jet-jet mass resolution + jet flavor tagging Plus… We need very good forward calorimetry for e.g. SUSY selectron studies, and… ability to find/reconstruct photons from secondary vertices e.g. from long-lived NLSP ->  G

Can we use a “traditional” approach to calorimetry? (using only energy measurements based on the calorimeter systems) 60%/  E 30%/  E H. Videau Target region for jet energy resolution

Don’t underestimate the complexity!

Digital Hadron Calorimetry Physics requirements emphasize segmentation/granularity (transverse AND longitudinal) over intrinsic energy resolution. - Depth  4 (not including ECal ~ 1 ) + tail-catcher(?) -Assuming PFlow: - sufficient segmentation (#channels) to allow efficient charged particle tracking. - for “digital” approach – sufficiently fine segmentation (#channels) to give linear energy vs. hits relation - efficient MIP detection (threshold, cell size) - intrinsic, single (neutral) hadron energy resolution must not degrade jet energy resolution. 

GEM-based Digital Calorimeter Concept

GEM – production 70  m 140  m Copper edges Hole profile Exposed kapton

GEM – operation -2100V ∆V ~400V 0V

(10 x 10) – 4 active area = 96 channels Trace edge connector -> Fermilab 32 ch board 305mm x 305mm layer Disc/DAQ under design by U.W.

First 30cm x 30cm 3M GEM foils

Development of GEM sensitive layer 9-layer readout pc-board 3 mm 1 mm Non-porous, double-sided adhesive strips GEM foils Gas inlet/outlet (example) Cathode layer Absorber strong back Fishing-line spacer schematic Anode(pad) layer (NOT TO SCALE)

DHCAL/GEM Module concepts GEM layer slides into gap between absorber sheets Include part of absorber in GEM active layer - provides structural integrity Side plates alternate in adjacent modules

GDE (Design) (Construction) Technology Choice Acc CDR TDRStart Global Lab. Det. Detector Outline Documents CDRsLOIs R&D Phase Collaboration Forming Construction Detector R&D Panel Tevatron SLAC B LHC HERA T2K Done! Detector “Window for Detector R&D

CALICE SiW ECAL CALICE TILE HCAL+TCMT Combined CALICE TILE OTHER ECALs CALICE DHCALs and others Combined Calorimeters PFA and shower library Related Data Taking >2009 ILCD R&D, calibration Phase I: Detector R&D, PFA development, Tech. Choice Phase II Phase 0: Prep. Timeline of Beam Tests , tracking, MDI, etc From Jae Yu

Many challenging and exciting projects on Linear Collider R&D! -> Detector design -> Prototype construction/testing -> High speed electronics -> Computer simulations (need help!) -> Physics studies (need help!) x22812 Room 241