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Particle Physics Open Day

The Oxford Particle Physics

Program

Farrukh Azfar

Director of Graduate Studies for

Particle Physics(thanks Prof. Daniela Bortoletto& PP colleagues)

Higgs as a new tool for

discovery

Identify the new

physics of dark

matter

Oxford is addressing the science drivers of particle physics

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The physics of

Neutrino mass

Understanding

cosmic

acceleration

Explore the

unknown: new

particles and

new interactions

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The Standard Model

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The Standard Model

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1964 SM Theory

1984 LHC Design

1996 Start LHC construction

2009: first collisions

2012: Higgs Discovery

Why look beyond the Standard Model?

Experimental Evidence

Non-baryonic dark matter

(~23%)

Inferred from gravitational effects

Rotational speed of galaxies

Orbital velocities of galaxies in

clusters

Gravitational lensing

..

Dark Energy (~73%)

Accelerated Expansion of the

Universe

Neutrinos have mass and mix

Baryon asymmetry

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The Higgs boson The discovery of the Higgs Boson raises many questions

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The Higgs boson The discovery of the Higgs Boson raises many questions

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27km

Circumference

ATLAS

LHCb

The Large Hadron Collider A Discovery Machine

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Operates above energy scale of SM:

13 TeV in 2015

Probes new physics

ATLAS

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Barr, Bortoletto, CooperSarkar, Gwenlan, Hays,

Huffman, Issever, Nickerson, Shipsey,

Viehhauser, Weidberg

The Oxford ATLAS Group Our goals:

Shed light on new Higgs boson

Measure its properties

Improve our understanding of SM

Discover new physics beyond SM

Can we make & discover Dark Matter?

Are there heavier Higgs bosons?

Is nature supersymmetric?

Look for more Exotics signatures

Build key parts of next generation LHC

detector11

Supersymmetry

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New symmetry of

space and time

(extends rotations

and boosts)

Links fermions and

bosons

Provides

superpartner to

each SM particle

Lightest partner

Dark Matter

Path to unification

& string theory Dark matter

Oxford Higgs Group 3 academics: Bortoletto, Hays, Shipsey

2 Postdocs: Schopf (Hbb) and Artoni

(HZZ, H )

8 students: Ambroz, Foti, Karava, Marchese,

Tosciri, Wolker, Zemaityte, Zgubic

Measured the Higgs coupling to b-quarks!

More data will allow us to:

Probe the Higgs coupling to the second

generation

Test for physics beyond the SM (using for

example Effective Theory Interpretation)

Search for new scalar particles

Use of advanced analysis techniques (neural

networks) and major contributions to common

physics objects

Strong collaborations with theorists13

Higgs in run 2 of the LHC Oxford recent highlight contributions

Hbb observed(expected) significance: 5.4(5.5)

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Higgs in run 2 of the LHC

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Until 6 years ago the

Yukawa coupling was

essentially a conjecture

no such term had ever

been seen in nature

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Oxford SUSY group 2 Academics: Barr, Gwenlan

2 Postdocs: Backes (Electroweak

SUSY and triggers) and Nagai

(Strong SUSY)

5 DPhil Students: Liu, Nelson,

Gallardo, ONeill, Wuerzinger

Oxford students lead small teams &

have many world-first searches @LHC

Squarks, Gluinos, Scharm,

Higgsinos, Multijets,

Also contribute to ATLAS experiment

e.g. triggering on events with Dark

Matter

Possible to combine with theory studies

Supersymmetry example: Higgsinos Spin 1/2 partners of Higgs bosons

Excellent Dark Matter candidate

Should be at approx. same mass scale as Higgs

boson(s)

Search for leptons + invisible (weakly interacting)

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As of this year we are just starting to get sensitivity

Lots of other

electroweak/Higgsy

SUSY processes just

getting ripe for analysis

No Higgsino

in red area

Still to be

explored

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Instrumentation: Oxford Physics

Microstructure Detector Laboratory (OPMD)

A state-of-the art facility enhancing the development of new radiation sensors in Oxford and the UK

Development of novel detectors for particle physics, photon science, and astrophysics

Currently focusing on

Depleted Monolithic Pixel Detectors for ATLAS

Ultra Fast Silicon Detectors

CCD for LSST Sharma

ShipseyBortoletto

Arndt

Placket

Weatherill

Wood

Metodiev

What to expect as a Student in ATLAS Students work in small friendly teams

Have a big impact

Gain high visibility in ATLAS

Take responsibility for projects or

detectors

Long term stay at CERN

Shifts at the detector

21ATLAS CONTROL ROOM START OF RUN 2

LHCb

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try

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The LHCb experiment

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Several trillion B hadrons have

so far been produced at LHCb.

to make precision measurements of CP violation

to search for New Physics in rare B decays

Critical for allowing this physics are particle identification and excellent vertex reconstruction.

The RICH detectors were designed and build in Oxford

VELO is a major Oxford activity

LHCb is a general purpose experiment for

examining the forward region of the proton-proton

collisions

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CP violation!

CP-violation in beauty hadrons

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In beauty system, the SM predicts sizable CP-violation.

And this is what we see!

Rate of decay and CP-conjugated process are clearly different !

Often, the SM predictions are precise.

The goal then is to make Correspondingly precise measurements.

Any Inconsistencies would indicate New Physics at work !

B0K+-

B0barK-+Signal + residual

background

The apex of the CKM triangle is the world average measurement of their

value (from pre-LHC measurements of the triangles sides and angles). Large error on one of the key ingredients of a precise , determination!

Oxford driven analysis has measured =74+5 -6 deg using BD0K this

already equals the precision of previous measurements. Aiming to reduce

error to 3 deg

Precise CKM measurements

LHCb offers fantastic opportunities for graduate students

All graduate students are working on high-profile

analyses of LHC data.

Graduate students participate fully in the running

of the experiment at CERN.

BELOW: 3rd yr D.Phil. in the LHCb control

room

The Oxford LHCb Oxford enjoys an great position in the international

collaboration.

3 Academics + 1 RSF (Harnew, Wilkinson, John, Malde)

8 D.Phil (Bijorn, Gruberg Cazon, Murphy, Pili. Pullen,

Rollings Fischer, Scantlebury-Smead )

The physics of neutrinos T2K

HyperK

PROTODUNE

DUNE

SNO+

MICROBoNE

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T2K Neutrino Oscillation experiment

Measure disappearance of muon neutrinos to determine 23 and m2

Measure electron neutrino appearance

Determine if neutrinos and antineutrinos behave the same. In fact, there is a

chance to find CP violation in THIS experiment.

The group is also studying future neutrino experiments for CP violation discovery.

T2K results so far

T2K results so far

CP conserving values outside of 2 region

for both hierarchies

Upgrade SK to Hyper-K Start ~2022Total water mass of 0.99 Mt

Future = Liquid Argon in USA and Water Cherenkov in Japan

DUNE: planned long baseline

experiment. Start ~2022

4x10kT

PROTODUNE

770 t LAr mass

Exposed to H2 (DP)

and H4 (SP)

testbeams at CERN

(, K, , , )

Prototyping

production and

installation

Validating the design

and long-term

operational stability

Understanding,

calibration, dE/dx,

PID etc.

PROTODUNE SP

2018 data taking

Daniela Bortoletto, LISHEP 2018,

Salvador34

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The Dark Universe

LZ

LSST

7-tonne two-phase Xenon TPC (5.6t fiducial) to search for xenon

nuclei, recoiling in response to collisions by dark matter particles.

Oxford provides crucial TPC sensors/readout and simulations tools.

Full exploitation requires significant simulation and analysis effort.

Oxford group now focussing on analysis/simulation tasks.

Dark Matter Search with LZ (LUX-ZEPLIN)

Oxford team:Hans Kraus

Amy Cottle

Theresa Fruth

Andrew Stevens

Eilish Gibson

Matthew Tan

LZ at the Sanford Underground Research Facility48

50

ft b

elo

w

Installation and

Commissioning in

2019 / early 2020.

Plenty of D.Phil.

opportunities with

analysis of early

data!

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Exploring the nature of dark energy

Oxford LSST Camera Test Stand

Particle Astro Synergy

PP: Azfar/Tseng/ShipseyAstro:Davies/Dunkley/Fender/Ferriera/Jarvis/Lintott/ Miller

Dark Energy LSST Meeting Oxford July, 2016

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Mu3e Features

Charged lepton flavor violating

Via neutrino mixing

Suppressed by (m2/ mW

2)2

Expected BR(+e+e-e+) < 10-50

Importance

Observable BR only from New

Physics

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Welcome to Oxford Particle Physics