2015-04-27 Alan Astbury R. Keeler Scienst 1934 -- 2014

1 Scientiic Antecedents

• Graduate of Nantwich and Acton Grammar School • Alan told me he was parcularly lucky to have excellent teachers • First Class Honours degree in at the University 2015-04-27 of Liverpool • PhD research supervisors (): R. Keeler • Sir Alec Merrison, • Hugh Muirhead (was a member of Powell’s group that discovered the pion and an acve member of UA1). He wrote a well known textbook.

2 Outline

Overview of Alan’s scienfic work in historical order.

• His worked covered nuclear physics to high energy parcle physics

2015-04-27 Two themes emerge:

• Alan worked on the leading scienfic problems of his me. R. Keeler • He used the most technologically advanced apparatus that was available

3 Liverpool Synchrocyclotron

Photo of the rotang capacitor used to modulate the RF at the 400 MeV accelerator. An external beam could be

extracted.

2015-04-27 R. Keeler

4 Liverpool (graduate Student)

Capture Rates for Negave Muons in Various Elements

Proc. Phys. Soc. 72, (1958)

• Physics interest was tesng the theory of universal weak 2015-04-27 interacons • External negave parcle beam (86 % pions, 11% electrons, 3% R. Keeler muons) • Muons stopped in target and decay me measured

5 Liverpool ( Leverhulm Research Fellow) Angular Distribuon of Neutrons Following Nuclear Capture of Polarized Muons Phys. Rev. Leers 15, 1959 Tesng V-A weak coupling

Results support violaon

µ− + p → n+ν 2015-04-27 ! ! ! Harwell neutron counter with N(θ)∝1+ασ i p/ p gamma ray suppression R. Keeler 15% polarizaon for stopped muons in sulfur target !⊗!magnetic!field

Asymmetry in direcon of n emission

6 Liverpool ( Leverhulm Research Fellow)

A measurement of the Total Cross Secon for the Producon of Neutral Pions in Proton-Proton Collisions at

383 MeV Proc. Phys. Soc. 78 (1961)

Uses a measurement of gamma rays at a special angle 2015-04-27

γ dσ (θ ) R. Keeler σ = 2π ppπ 0 dΩ where cos−1( 1/3) {37° ,102 ) !θ = ± = °

Result: 59±9 μb

Mandelstam Resonance Theory 7 cannot account for all of the producon cross secon Berkeley

Search for Neutrino-induced Reacons

Physical Review Leers 11 (1963) p + n ν µ + → µ +

! 2015-04-27 • W mass > 1.1 GeV

OR R. Keeler • cross secon less than 4x10-32 (~10-40)

8 Berkeley

Using the 184 inch synchrotron

Commissioned a bent-crystal spectrometer

Measured 2015-04-27 Pionic X-rays R. Keeler

Results presented at conferences.

9 Rutherford Appleton Laboratory RAL (Research Associate)

Nimrod Weak Focusing proton synchrotron 2015-04-27 7 GeV, 1012 / pulse R. Keeler 0.5 Hz pulse rate.

Start operaons 1963

10

CJSD/JD retirement/July 02/pg4 RAL Nimrod

Two Pion Decay of the Meson K 0 2015-04-27 ! 2 Phys. Rev. Le. 14 (1965) Throughout its life, physics programme was directed mainly to studying baryon resonances • Nimrod beamlines in 1964 R. Keeler • First generation experiments measured π ±±pKp,and pptotal cross-sections, differential Confirmaon of CP violaon in K-long decays cross-sections and polarisation • Also Kd± total cross-section, ππ− pn→→0 and η nnppn and charge exchange processes momentum spectrum 1.5 < p< 5.0 GeV/c K 0 CJSD/JD retirement/July 02/pg5 ! 2 5 m evacuated decay chamber Decay parcles are momentum analyzed by two 11 spectrometers with bending magnets and sonic spark chambers

RAL CP Violation

• 54±9 2pi events observed • BR = (2.08±0.35)x10-3 Today’s value=(1.967±10)x10-3

2015-04-27 K2pi R. Keeler K3pi Ke3 Kmu3

pions in the forward 12 direction RAL (Tenured PSO)

Measurement of the Electron Asymmetry Parameter in the Decay of Polarized Hyperons. Σ− Nucl. Phys. B39 (1972)

Cabbibo Theory • 1.13 GeV/c pions − • Measured polarizaon is small Σ 2015-04-27 P=-0.32±11 R. Keeler − p+ − K + π + → Σ + Σ− → n+ e− +ν 43 decays observed g Result: A = −0.4+0.52 g −1.5 ! V g 13 A = +0.3 Predicon: g ! V RAL Nucleon-Nucleon

Small Angle Proton-Proton Scaering at 7.85 GeV/c Phys. Les. 14 (1965)

Measure the cross secon in the very forward direcon. 2015-04-27 Strong-EM interference region will give phase

Total cross secon can be calculated from the opcal theorem R. Keeler

14 RAL

Another group reported anomalous result that violated the

Opcal Theorem

2015-04-27 Results here are consistent with other data and predicted dispersion relaon R. Keeler

15 CERN PS Physics CERN Yellow reports: 71-25, 72-10, 74-10 Papers

_ + − + Differenal Cross Secon for between 0.8 and 2.4 GeV/c !pp → π π ,K K

Phys. Le B 47 (1973) 2015-04-27

_ Interpretaons of the Differenal Cross Secons for . !pp → π π R. Keeler Phys. Le. B 47 (1973)

− + Some Observaons on the Differenal Cross secons for . !pp → K K Phys. Le. B 49 (1974)

16 CERN PS

Electrostacally separated anproton beam Wire chamber based magnec spectrometer

2015-04-27 R. Keeler

17 CERN PS

Angular

distribuons measured

at 10 incident 2015-04-27 momenta.

R. Keeler Phase shi analysis done.

18 CERN PS

Phase shi analysis

There are many more states available in 2015-04-27 anproton proton

annihilaon than there R. Keeler are in proton-proton interacons.

This table keeps track of various fit results 19 RAL

Kaon-nucleon interacons searching for a forbidden S=1, I=0

baryon state

Polarizaon in K+n Charge Exchange Scaering Between 0.851 2015-04-27 GeV/c and 1.351 GeV/c

Phys. Le. B R. Keeler

No forbidden states detected.

20 UA1 (co-spokesperson)

Anproton-proton

collider 540 GeV Centre of Mass 2015-04-27 R. Keeler

21 UA1 Hadron Calorimeter

UK provides:

• Hadron Calorimeter (Iron-Scinllator with wavelength shier readout)

• Return yoke for a transverse magnec field 2015-04-27 • Inside the box were a: • Lead-Scinllator R. Keeler electromagnec calorimeter • Central Dri Chamber

22 UA1 Hadron Calorimeter 0.8 Resoluon = E(GeV ) !

2015-04-27 R. Keeler

Missing Transverse Energy Resoluon of each component is Gaussian σ = 0.4⋅ E i !!E!measured!in!GeV with ! ∑ i T where the sum is typically < 100 GeV 23

UA1 Trigger

50 kHz event rate Reduced to 3Hz • Tape wring speed

Calorimeter trigger was combined with a muon trigger 2015-04-27

Eventually a 168E (emulator) was used as a high level trigger R. Keeler

24 UA1 startup Group Enormous ! T n ! i s ! t h e ! p r o ! b < a b n i li t y > ! o = f ! o b 6 s e . 5 r v 7 i n g ! n ! c h a r g e d ! t r a c k s 25 R. Keeler 2015-04-27 UA1 W Missing Transverse Energy (Martyn Corden – U. Birmingham)

2015-04-27 R. Keeler

26 UA1 W

Experimental Observaon of Isolated Large Transverse Energy Electrons with associated Missing Energy at √s=540 GeV.

Phys. Les 122B (1983) 2015-04-27 R. Keeler

M = 81+5 !GeV/c2 ! W −5

27 Telegram to CERN DG from 2015-04-27 Margaret R. Keeler Thatcher, PM UK 28 Margaret Thatcher

2015-04-27 R. Keeler

29

British PM 2015-04-27 telegram R. Keeler to Alan

30 W discovery

2015-04-27 R. Keeler

31 UA1 Z

Experimental Observaon of Lepton Pairs of Invariant Mass around 95 GeV/c2 at the CERN SPS Collider

Phys. Les B126 (1983) 2015-04-27

2 M = 95.2±2.5!GeV/c R. Keeler ! Z

32 UA1 W & Z Electron angular distribuon W is spin 1 parcle ρ and Sin2(θ ) measured

W 2015-04-27 R. Keeler

33 UA1 Di-Jets Spin 1 Gluon exchange Factorizaon à leading order structure funcons

2015-04-27 R. Keeler

Bill Sco RAL

34 UA1 3-Jets

Scale breaking

Running of the strong coupling constant 2015-04-27 R. Keeler

35 UA1 3 Jets

2015-04-27

Gluon R. Keeler Bremsstrahlung

36 Alan arrives in Victoria (1983)

Earliest group photo I could find

2015-04-27 R. Keeler

37 UA1 Ramping Run

SPS cycled between 200 and 900 GeV.

2015-04-27 R. Keeler

38 UA1 Bose-Einstein Correlations

First Student in Canada - Margret Fincke-Keeler Bose-Einstein Correlaons in An-p p Interacons at √s=0.2 TeV to 0.9 TeV Nucl. Phys. B 226 (1989)

2015-04-27 R. Keeler

39 TMP 2,2,4,4 tetramethylpentane

• Does it compensate?

2015-04-27 R. Keeler

40 No, it does not. SLD

Designed and built liquid argon- lead electromagnec calorimeter in collaboraon with Caltech. 2015-04-27 R. Keeler

41 OPAL (Director of TRIUMF)

LEP: Electron-positron collider Z pole and then above the WW threshold

Victoria Group worked on:

• Silicon microvertex detector upgrade 2015-04-27 • Responsible for near-real me data reconstrucon

Our tau physics work started with three technical notes that Alan took R. Keeler a very big interest in: TN 139 (1993) A New Clustering Algorithm for tau Decays A. Astbury et al TN 186 (1993) A New Clustering Algorithm for tau Decays : II R. Sobie TN174 (1993) A Study of Electromagnec Shower Profiles in the Electromagnec Barrel Calorimeter 42 M. Vincter, A. Astbury, R. Keeler, R. Sobie OPAL

Some thesis topics that Alan was involved with:

1. The W Boson Spin Density matrix at OPAL (I. Bailey – Lancaster)

2. Search for Excited Charged Leptons in Electron-Positron 2015-04-27 Collisions (B. Vachon – McGill) 3. A Precision Measurement of the Rao of the Effecve R. Keeler Vector to Axial-Vector Couplings of the Weak Neutral Current at the Z0 Pole (M. Vincter – Carleton) 4. Measurement of the Neutral Current in the Standard Model using the Tau Polarizaon Asymmetries Determined from − − the decay (M. τ → ρ ντ Rosvick – industry) 5. Measurement of the Product Branching Rao f (b → Λ )BR(Λ → Λl−ν X) (Johannes ! b b Steuerer – Industry) 43

ATLAS

Hadronic Endcap

Calorimeter 2015-04-27 R. Keeler

44 Module 0 - prototype

First module made at TRIUMF and tested in the North Hall at

CERN 2015-04-27 R. Keeler

45 A Sample Talk

A typical aside -

2015-04-27 A reference to King Canute R. Keeler

Not sure what inexorable event was being referred to

46 ATLAS

UVic summer 2013

- contribung good council and sharp physics insight 2015-04-27 R. Keeler

47 48 R. Keeler 2015-04-27