# Presentation: 301831

## DPF 2002

**New Detectors for New Physics **
**Dan Green**
**Fermilab**

## Outline

**Introduction – Detectors and the SM Particles**
**Physics Questions and Detectors to Answer Them**
**EWSB (Higgs, SUSY) – CDF/D0 -> ATLAS/CMS**
**Baryon Asymmetry and CP Violation – CLEO, Belle/BaBar -> LHCb, BTeV –  Rare K, CKM, Lepton Flavor Violation **
**Neutrino Mass, Mixing – SuperK -> K2K -> JHF, MiniBoone Numi/Minos,  NGS (ICARUS,OPERA), SNO. AMANDA/RICE -> ICECUBE**
**QGP – RHIC(STAR/PHENIX) -> LHC HI Program (ALICE)**
**Dark Matter -  DAMA, CDMS, GLAST, AMS, MILAGRO **
**Extra Dimensions – Cavendish, AUGER, Colliders**
**Gravity Waves – LIGO, VIRGO, GEO  -> LISA**
**Future Developments and New Physics**
**Lepton Colliders – LEP/SLC -> LC**
**Higher Mass States - ?? Limits at hadron colliders.**

## New Detector Technologies

**Bruce Schumm (UC Santa Cruz)**
**    ****Mike Tuts (Columbia)**
**CDF and D0**
**ATLAS and CMS**
**BTeV and LHCb**
**TRD, RICH,TOF**
**Diamond pixels**
**Radiation hard electronics and optical links**
**New Accelerator Technologies - crucial**
**Snowmass 2001 Experimental Groups **
**LC R&D – next talk**

## Introduction

**Whatever happens, new Physics will decay into SM particle- quarks, leptons and gauge bosons.**
**We need to trigger, detect and do ID of the SM Particles.**
**Calorimetry will be used to measure electrons and photons as well as jets of quarks and gluons. Neutrinos will be inferred from missing E****T****. Muon particle id will use absorbers and “mip”. Tau id will come from “narrow” jets, ********->********W, W->********, ********, A. **
**Heavy flavor – b,c, ******** - will have displaced vertices. Momentum of charged tracks may be used in kinematics of jets, ******** and e.**

## Recent Detector Improvements

**Si: CCD, Pixels, Strips (LHC ~ -10****o****C),  Oxygenated -> cryogenic ?, diamond ?**
**Gas: MSGC - GEM, TRT, RPC, CSC**
**Calor: LAr, CsI, PbWO4, Scint (fibers), “Energy Flow”, Quartz fibers.**
**Transducers: VLPC, APD, HPD, MAPMT**
**Data FE + TX: Commercial deep submicron (radiation hard) IBM process, VCSEL optical links**
**ID: RICH, TRD, TOF, DIRC**
**Bolometry: Ge, NaI -> mK Temp, phonons + ionization ( ref. Cal 2000) **

**Concentrate on LHC/EWSB and calorimetry in what follows**

## LHC Detectors - Si Pixels

**The development of radiation hard Si pixel sensors and readout for the LHC experiments is the fruit of an intensive R&D program. Lesson of SSC and LHC is that a good R&D program is required.**

**Operate at low temperatures**

## CMS – All Si Tracker

**The existence of large volume commercially available sensors, 0.25 ********m IBM radiation hard FE circuits and optical links, and improved sensor structures operated at high bias voltage and low temperatures make this system (200 m****2****) feasible.**

## ATLAS Calorimeters – Noble Liquids

**ATLAS – electrode (accordion) R&D for high speed readout.**

## CMS Crystal Calorimetry

**Transducer – APD, developed for CMS, R&D**

**New crystal – PbWO4 developed for CMS, R&D – fast, compact and rad hard**

**Crystal + APD**

## Evading “Mixed Media”

**If you identify energy as hadronic, you can correct for non-linearity due to different ECAL, HCAL but not non-compensation, e.g. CMS data.**

** ****dF****o**** still causes dE but no additional penalty.**

- EE

- EH

## Non-compensation and dE/E

**F****o****(E). As E ->********, F****o**** -> 1 and dE -> 0 as log(E). e/h less important as energies increase. R&D for CMS on HF.**

## Dijet Mass at LEP, CDF/D0

**LEP – use beam constraints. dM/M ~  3.6%**
**CDF – no constraint available, no FSR cuts made, dM/M ~ 14 %. Crucial for H->bb, first find Z->bb.**

## Energy Flow Improves Jet Mass

-  **Tracking 10% @ 1 TeV, ECAL 5% stochastic, 1% constant, and HCAL 50% stochastic and 3% constant.**
**Note that a jet has <z****max****> ~ 0.22. For charged particles < 100 GeV (jets < 0.5 TeV) use tracks to measure E.**
**“****Old wine in new bottles”. Treat detector as a totality, not the sum of incoherent subsystems. The whole is then greater than the sum of parts.**

## Particle ID within a Jet

**A jet cone of**
**    ****radius 0.9 has**
**    ****~ 400 towers**
**    ****of HCAL and**
**    ****~ 10,000 towers**
**    ****of ECAL in CMS.**
**    ****Tower occupation**
**    ****is sparse -> can**
**    ****identify tracks with**
**    “****isolated” towers**
**   ****(calor must be fine**
**    ****grained)**

**(********,********) Lego of ECAL and HCAL within a jet**

## Track Matching

**For a Monte Carlo sample of 120 GeV Z’ match tracks in ******** and ******** to “hadronic” clusters within the jet – cone size ~ 0.9. Units are HCAL tower sizes.**

- d

- d

**E****T****(GeV)**

## Improved Dijet Mass

**There is a ~ 22 % improvement in the dijet mass resolution. This is welcome but clearly implies that calorimeter resolution is not the whole story**.

**Mean 81.7 GeV, (21%)                       Mean 105.5 GeV (17%)**

## Hadron Collider- Dijet dM/M

**A series of Monte Carlo studies were done in order to identify the elements contributing to the mass error. Quote low P****T****, Z -> JJ. dM/M ~ 13% without FSR**.

**FSR is the biggest effect. The underlying event is the second largest error (if cone R ~ 0.7). Calorimetry is a minor effect. Fold terms in quadrature.**

## CDF Study – Photon+Jet

**CDF studied energy flow using shower max (particle id) and tracking information. A similar ~ 24% improvement was seen.**

## Missing Transverse Energy

**Study done for CMS. Three major sources of missing E****T**** – incomplete angular coverage, B field “sweeping” to small angles and calorimetric energy resolution.**
**Clearly need radiation hard calorimetry to go to smaller angles – particularly as C.M. energy increases. Presently dose < 1 Grad at |********| = 5.**

## Improved Missing ET

**Use energy flow for all energy deposits, if matched. Missing E****T**** is a global variable. There is a 16% improvement in the missing E****T**** significance. More study needs to be done.**

## LA - High Speed Readout

**ATLAS – LAr accordion readout for LHC, 25 nsec bunch spacing – R&D**

- Io- t

## CMS-HPD Pulse Formation 

**Photocathode**
**Si Diode        E field**

**10 kV    ****h**

**HPD  - R&D for CMS HCAL. The p.e.gain ~ 10 kV and ionize a Si diode, with h collected.**

## CP Violation  

**SM CP violation is not sufficient to explain the observed B asymmetry. Thus look for new sources of CP violation (SUSY ?) – full court press, Belle/BaBar -> LHCb, BTeV and CKM, BNL 787.**

## Upgraded Detector for e+e- @1036

** **_**BABAR                 SUPERBABAR            Reason for change**_
**     ****Silicon                   Si pixels                        occupancy**
**     ****Drift Chamber     Si tracker (or TPC)     accumulated charge**
**     ****DIRC                    superDIRC                   remove water standoff box**
**     ****ECAL CsI(Tl)      LSO                              long decay time not rad hard**
**     ****IFR (K ****L****0 ********)          IFR’                              RPC’s******** sci fi (occupancy)**

**L increase of 100 x will be hard -> heavily upgraded detector**

## CP Violation – Rare K Decays

- BNL 787 -> BNL 949, CKM – high rate capability detectors,

- CKM detector

**CKM is an experiment in veto. Over constrain CKM with K and B decays.**

- K

- 

## Lepton Flavor Violation 

**Neutrino Mass -> lepton Flavor Mixing. BNL871, BNL865, FNAL799, MEGA, MECO – seesaw. PSI -**
** ****or **

**Straws, crystals**

## Neutrino Factories

**Intense  and pure**
**   ****beams needed for **
**   ****long baseline**
**   ****neutrino oscillation**
**   ****experiments – **
**   ****e.g. Proton Driver for NUMI,**
**   ****JHF, NuFact**
**Need a large area cheap,**
**   ****fast detector of ******** decays. **
**   ****OPERA (Pb/emulsion) in Gran**
**   ****Sasso.**
** ****LA – TPC (Icarus)**
**   ****Water Cerenkov?**
**   ****Fe/Scint?**

## Icarus EM Shower

**Icarus LA TPC allows for tracking and calorimetry for neutrino detectors with enormous granularity and detail.**

## STAR Tracking @ RHIC

**QGP ? Critical Temp ~ 160 MeV**
**Need extremely good tracking.**
**C.M. energy will increase ~ 50x at LHC w.r.t. RHIC. ALICE detector emphasizes tracking and low Pt, CMS/ATLAS focus on muons and high P****T**** calorimetry. **

## DM – Dynamic Measures

**Dynamic measure of mass (rotation curve, grav lensing) leads to conclusion that we do not know what the Universe is made of! **
**(forget dark energy...)**

## SUSY at LHC 

**SUSY will be **
**    ****extensively**
**    ****searched for at**
**    ****LHC and LC.**

**n.b. – SUSY is a good dark matter candidate giving correct relic abundance since neutralino annihilation is weak. Favors light SUSY.**

## Dark Matter – Direct 

**Double beta decay (Majorana Expt. – Ge), Dark Matter**
**Gran Sasso, CDMS – cryogenic bolometry**
**Look for elastic recoils, scale  ~ 10 keV. Present cross section limits ~ 10****-6**** pb (mK – phonons)**

## SUSY and DM

**Elastic scatter of neutralino off nuclei in direct detection. Next generation, 10 kg, T > 10 keV.**
**With ********  < 10****-8**** pb, M > 100 GeV, may still need  ~ 100x improvement if many SUSY points are to be uncovered.**

**If next generation is successful, many SUSY points (B,E,I ...) will be uncovered. Complements HEP searches.**

## High Energy Astrophysics

**Also look for DM via annihilations in sun, galaxy. Use Crab to calibrate. Cover energy range 0.1 GeV to 10 TeV.**

## AUGER – Black Holes

**LHC will cover ~ 10 TeV – DY for example. A 10****19**** eV cosmic ray (AUGER) has ~100 TeV C.M. energy**

**Extra dimensions –number,n, and size, M****D****, of**

## Gravitational Waves – LIGO, VIRGO

**Signals of 10****-22**** expected. Minimum at ~ 200 Hz – competition between seismic and shot noise. New window on the Universe. Improve with longer lever arm, reduced seismic. LIGO -> LISA, new ******** window**

## Future Developments

**At the LC, cross**
**    ****sections w.r.t**
**    ****LEP are down**
**    ****by large factors**
**    ****- 1/M****2**** scaling.**
**    ****Therefore, high**
**    ****L is needed – e.g.**
**    ****HH production**
**    ****(HHH coupling).**
**    ****A strong detector**
**    ****R&D program is**
**    ****needed (Snowmass)**

## LC Vertex Detector

**Need R&D to decide on best, e.g. b tags, pixel technology  for LC (e.g. CCD).**

## LC Outer Tracker

**Comparable resolution to CMS. B field choice and detector layer resolution to be decided (e.g. Si Drift – time stamp on track).**

## LC Energy Flow Study

**Boosted Z,W have**
**    ****dM/M ~ 3% . Look**
**    ****At **
**    ****Easier than at**
**    ****hadron colliders –**
**    ****FSR, fragmentation,**
**    ****pileup, underlying**
**    ****can be evaded. But,**
**    ****still need to confront**
**    ****multi-jet events.**

**Fine grained – size ~ Xo, ********, many depth segments ~ 3-d**

## Advanced Detector Research - DOE

- HEPAP recommends R&D effort
- DOE supports ADR program
- Lesson learned from SSC, LHC. For example, commercial radhard electronics process is crucial and ~ “sole source”.

## Exploring New Mass Scales

**Higher Mass -> higher luminosity -> radiation damage and occupation increases.**
**Fundamental 2 body production of new mass states goes as square of mass**

## New Physics in (s,L)

**In hadron colliders L and/or C.M. energy increases are both possible.**
**For masses ~ C.M.  Energy, L rises rapidly -> Energy is most important.**
**For masses << C.M. energy, L goes as the square of the mass.**

## Increased p-p L, s?

**Will require calorimetry which can withstand > 10 Mrad (ECAL) and > 2 Mrad (HCAL) for |********|<3.**
**Hermiticity (Missing E****T****) will require coverage to smaller angles as the C.M. energy increases and the “plateau” extends.**
** ****Forward calorimetry will need to endure > 1 Grad. Dose ~        .**
**The jump to higher masses will be hard.**

## Summary and Conclusions

**New detectors are on line – BaBar/Belle, CDF/D0 and many others.**
**The R&D for LHC detectors has been fruitful – e.g. ATLAS/CMS, LHCb, ALICE.**
**Many new detectors designed to address new Physics are in design or construction. Non-accelerator experiments are assuming a new importance.**
**New and vigorous R&D is needed for the design of the LC.**
**As the mass scale of new Physics increases, the required increase in luminosity will challenge the new detectors. **