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Searches for Supersymmetry

Oliver Buchmueller∗

Imperial College London

E-mail: [email protected]

on behalf of the ATLAS and CMS Collaborations

Since its first physics operation in 2010, the Large Hadron Collider at CERN has set a precedent in searches for supersymmetry. This proceeding report provides a brief overview on the current status of searches for supersymmetry at the LHC.

The European Physical Society Conference on High Energy Physics -EPS-HEP2013 18-24 July 2013 Stockholm, Sweden

∗Speaker.

  • c
  • ꢀ Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.

http://pos.sissa.it/

Searches for Supersymmetry

Oliver Buchmueller

  • MSUGRA/CMSSM: tan(ꢀ) = 30, A = -2m0, µ > 0
  • Status: SUSY 2013

0

1000
900 800 700 600 500 400 300

ꢃꢂ

95% CL limits.ꢄSUSY theory not included.

LSP

Expected

ATLAS Preliminary

  • L dt = 20.1 - 20.7 fb-1
  • s = 8 TeV

0-lepton, 2-6 jets

ATLAS-CONF-2013-047

Observed Expected

,

ꢁ

0-lepton, 7-10 jets

arXiv: 1308.1841

Observed Expected

0-1 lepton, 3 b-jets

ATLAS-CONF-2013-061

Observed Expected

1-lepton + jets + MET

ATLAS-CONF-2013-062

Observed Expected

1-2 taus + jets + MET

ATLAS-CONF-2013-026

Observed Expected

2-SS-leptons, 0 - ꢅ 3 b-jets

Observed

ATLAS-CONF-2013-007

  • 0
  • 1000
  • 2000
  • 3000
  • 4000
  • 5000
  • 6000

m0 [GeV]

Figure 1: 95% C.L. limits for different ATLAS searches defined in the CMSSM

1. Introduction

The landscape of searches for Supersymmetry (SUSY) has changed dramatically since the
Large Hadron Collider (LHC) at CERN began physics operation in 2010. By the end of 2011 the

experiments CMS [1] and ATLAS [2] had collected about 5 fb−1 of integrated luminosity each at a center-of-mass energy of 7 TeV. In 2012 the LHC operated at a center-of-mass energy of 8 TeV and each experiment collected approximately 20 fb−1 of data at this energy.
In this proceeding report I will focus on the status of searches for SUSY at the LHC. A more detailed and comprehensive overview is provided in the September 2013 update of the experimental review for SUSY searches in the PDG [3]. For more details on LEP and Tevatron results see also earlier PDG reviews [4].

2. Summary of R-parity conserving searches

If the multiplicative quantum number of R-parity, R = (−1)3(B−L)+2S, where B and L are baryon and lepton numbers and S is the spin, is conserved the lightest SUSY particle (LSP) is stable and often assumed to be a weakly interacting massive particle. The LSP escapes undetected through the experiment, leading to final states with several hadronic jets, large missing transverse energy, and possible leptons and photons in the final state.

2

Searches for Supersymmetry

Oliver Buchmueller

mLSP!

[GeV]!

Direct squark!

Gluino mediated !

mSUSY = mq˜

mSUSY = mg˜

q˜ !

g˜ !

1000!

!

1

u˜ !

ATLAS-CONF-2013-047 !

L

1

0

0

¯

˜

b !

!g˜ !

0

CMS-PAS-SUS-12-024!

˜

ATLAS-CONF-2013-037 !

t !

0

¯g˜ !

!

1

750!

Direct stop in “gap”!

ATLAS-CONF-2013-061!

mSUSY = mt˜

0

˜

ATLAS-CONF-2013-068!

!

!

t !

0

CMS-PAS-SUS! -13-011!

˜

t !

!

!

Direct slepton!

500!

lL !

˜

Direct χ! ±/χ02

BR=100%!

1

ATLAS-CONF-!

02

mSUSY = mχ± = mχ

1

2013-049!

all limits are !

lR !

˜

observed nominal 95% CLs limits! RP conserved !

χ±1 χ2(light l)

0

˜

χ±1 χ2(heavy l)

0

˜

250!

CMS-PAS-SUS-13-006!

mSUSY!

[GeV]!

0!
0!

  • 1250!
  • 1500!

37

  • 750!
  • 1000!

  • 500!
  • 250!

Figure 2: Illustrative summary plot for the most important simplified model limits.

ATLAS and CMS have performed many searches looking for R-parity conserving SUSY sig-

natures. Figure 1 shows limits in the framework of the CMSSM, assuming tanβ = 30, A0 = −2m0, and µ > 0, for several ATLAS searches. In this constrained SUSY model gluino masses below ≈1.3 TeV are excluded for all squark masses, while for equal gluino and squark masses, the limit is around 1.7 TeV. Furthermore, squark masses below 1.6 TeV are excluded for all gluino masses. The CMS collaboration has not yet provided an interpretation of their 8 TeV searches in the CMSSM but the performance is expected to be very similar.
Another important interpretation approach, even less dependent on fundamental assumptions, is the characterisation of the searches in terms of simplified models. Such models assume a limited set of SUSY particle production and decay modes and leave open the possibility to vary masses and other parameters freely. Today, ATLAS and CMS have adopted simplified models as the primary framework to provide interpretations of their searches. Figure 2 shows an illustrative overview of limits for the most important simplified models that are considered.
For gluino masses rather similar limits, ranging from 1.2 TeV to 1.4 TeV, are obtained from different model assumptions. This shows that the LHC is probing a large region in SUSY parameter space for direct gluino production at the 1 TeV scale and beyond.
Limits defined in simplified models on squark mass are not only much weaker but also vary strongly depending on the assumed properties of the decay chain. As shown in Figure 2, limits on direct squark production only go up 800 GeV under the assumption of an eightfold mass-

3

Searches for Supersymmetry

Oliver Buchmueller

  • Summary of CMS RPV SUSY Results*
  • EPSHEP 2013

~g → qllν

λλ

SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb EXO-12-049 L=19.5 /fb EXO-12-049 L=19.5 /fb SUS-13-013 L=19.5 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-12-027 L=9.2 /fb SUS-13-003 L=19.5 9.2 /fb SUS-12-027 L=9.2 /fb SUS-13-003 L=19.5 9.2 /fb SUS-13-003 L=19.5 /fb EXO-12-002 L=4.8 /fb

122

~g → qllν

g → qllν λ123 g → qbtµ λ'
~

233

~

Prompt LSP decays

231

~g → qbtµ λ'

233

~g → qqb λ''

113/223

~g → qqq λ''

112 323

~g → tbs λ''

~g → qqqq λ''

q → qllν λ112 ~

122

~q → qllν

λ

q → qllν λ123 q → qbtµ λ'
~

233

~

231

~q → qbtµ λ'

233 112 122

~qR → qqqq λ''

~tR → µeνt

λλ

~

s = 7 TeV s = 8 TeV

tR → µτνt

tR → µτνt λ123

~

233

~tR → tbtµ λ'

CMS Preliminary

t → bτ λ'233

~

333

  • 0
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  • 1000
  • 1200
  • 1400
  • 1600
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*Observed limits, theory uncertainties not included Only a selection of available mass limits Probe *up to* the quoted mass limit

Mass scales [GeV]

Figure 3: Summary plot for R-parity violating CMS searches. The corresponding ATLAS results are similar.

degeneracy for first and second generation squarks. If, however, only a single squark is assumed to be light, this limit weakens to only ≈ 450 GeV for the best possible scenario of very light neutralinos. For the production of single bottom squarks the best limit improves to around 650 GeV due to better control of the SM background via the identification of b quarks in the final state.
For top squarks the situation is even more complex because of the many different decay chains that must be considered. While in the best case limits of up to 700 GeV are possible, there are also regions in SUSY parameter space where even for light neutralinos top squarks above a few hundred GeV cannot be ruled out by the LHC searches.
Pair production of chargino, neutralinos, and sleptons at the LHC, for masses of several hundreds of GeV, is at least two orders of magnitude smaller than for coluored SUSY particles (e.g. top squark pair production). Therefore, high statistics data samples are required to constrain these SUSY particles. Today, depending on the assumed scenario limits on these particles vary from around 700 GeV in the most optimistic case to only a few hundred GeV for more pessimistic decay topologies. Much more data will be needed to push these limits above the 1 TeV scale.
Further results of SUSY searches can be obtained from the public result pages of ATLAS [5]

and CMS [6].

3. Summary of R-parity violating searches

If R-parity is violated, new terms λi jk, λi0jk and λi0j0k appear in the super potential, where i jk are

4

Searches for Supersymmetry

Oliver Buchmueller

Preliminary

ATLAS SUSY Searches* - 95% CL Lower Limits

Status: SUSY 2013

ATLAS

R

√

  • L dt = (4.6 - 22.9) fb−1
  • s = 7, 8 TeV

R

Emiss L dt[fb−1

]

e, µ, τ, γ

  • Model
  • Jets
  • Mass limit
  • Reference

T

2-6 jets 3-6 jets 7-10 jets 2-6 jets 2-6 jets 3-6 jets 0-3 jets 2-4 jets 0-2 jets
-

˜q, g˜ ˜g

m(q˜)=m(g˜) any m(q˜) any m(q˜)

MSUGRA/CMSSM MSUGRA/CMSSM MSUGRA/CMSSM

  • 0
  • Yes

Yes Yes Yes Yes
20.3 20.3 20.3 20.3 20.3 20.3 20.3 4.7

1.7 TeV

ATLAS-CONF-2013-047 ATLAS-CONF-2013-062
1308.1841

1 e, µ

1.2 TeV
1.1 TeV

˜g

0

seh

χ˜0

q˜q˜, q˜→q

1

˜q

χ˜0

0

740 GeV

ATLAS-CONF-2013-047 ATLAS-CONF-2013-047 ATLAS-CONF-2013-062 ATLAS-CONF-2013-089
1208.4688 m( 1)=0 GeV

cr

χ˜0

g˜g˜, g˜→qq¯

1

˜g

χ˜0

0

1.3 TeV

m( 1)=0 GeV

ae

1 e, µ 2 e, µ 2 e, µ

˜g

χ˜0

χ˜±

χ˜0

χ˜±

±χ˜01

Yes
-

1.18 TeV 1.12 TeV

1.24 TeV

m( 1)<200 GeV, m( )=0.5(m( 1)+m(g˜))

g˜g˜, g˜→qq 1 →qqW

χ˜0

˜g

χ˜0

S

g˜g˜, g˜→qq(ℓℓ/ℓν/νν)

m( 1)=0 GeV

1

˜

e

˜g

tanβ<15

  • GMSB (ℓ NLSP)
  • Yes

Yes Yes Yes Yes Yes Yes

vi

˜

˜g

tanβ >18

GMSB (ℓ NLSP) GGM (bino NLSP) GGM (wino NLSP)
1-2 τ 2 γ
1 e, µ + γ

γ

20.7 4.8

1.4 TeV

1.07 TeV

ATLAS-CONF-2013-026
1209.0753

s

χ˜0

ul

˜g

m( 1)>50 GeV

c

-

χ˜0

nI

˜g

ATLAS-CONF-2012-144
1211.1167

4.8 4.8

619 GeV

m( 1)>50 GeV

χ˜0

GGM (higgsino-bino NLSP) GGM (higgsino NLSP) Gravitino LSP

˜g

1 b
0-3 jets mono-jet

900 GeV

m( 1)>220 GeV

˜

2 e, µ (Z)
0

˜g

5.8 10.5

690 GeV
645 GeV

  • m(H)>200 GeV
  • ATLAS-CONF-2012-152

  • ATLAS-CONF-2012-147
  • m(g˜)>10−4 eV

F1/2 scale

.neg

01

.de

¯

χ˜0

χ˜

˜g ˜g ˜g ˜g

  • 0
  • 3 b

7-10 jets
Yes Yes Yes Yes
20.1 20.3 20.1 20.1

1.2 TeV
1.1 TeV
1.34 TeV 1.3 TeV

ATLAS-CONF-2013-061
1308.1841 m( 1)<600 GeV

g˜→bb

χ˜0

χ˜0

¯

g˜→tt

1

0

m( 1) <350 GeV

χ˜0

0-1 e, µ 0-1 e, µ

χ˜0

m

¯

g˜→tt

1

3 b 3 b

ATLAS-CONF-2013-061 ATLAS-CONF-2013-061 m( 1)<400 GeV

χ˜+

χ˜0

¯

g˜→bt

1

m( 1)<300 GeV

χ˜0

χ˜0

1308.2631

˜

b1

˜

b1

˜

t1

˜

t1

˜

t1

˜

t1

˜

t1

˜

t1

˜˜

b1

˜˜

b

˜˜

0
2 b 0-3 b 1-2 b 0-2 jets 2 jets
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
20.1 20.7 4.7

100-620 GeV
275-430 GeV

m( 1)<90 GeV

b1

b1, b1→b

1

χ˜±

˜

χ˜±

χ˜0

2 e, µ (SS)
1-2 e, µ 2 e, µ

ATLAS-CONF-2013-007 1208.4305, 1209.2102

1, b1→t

  • m( 1 )=2 m(
  • )

1

1

  • s
  • n

kroi

χ˜±

χ˜0

˜ ˜

t1

t

1(light), t1→b

110-167 GeV

130-220 GeV

m( 1)=55 GeV

1

tauc

χ˜0

χ˜0

χ˜±

  • ˜
  • ˜

  • ˜ ˜
  • ˜

20.3 20.3 20.1 20.7 20.5 20.3 20.7 20.7

ATLAS-CONF-2013-048 ATLAS-CONF-2013-065
1308.2631

  • m( 1) =m(t1)-m(W)-50 GeV, m(t1)<<m(
  • )

t1 1(light), t1→Wb

t

1

1

ud

χ˜0

2 e, µ

χ˜0

qs

  • ˜ ˜
  • ˜

˜

225-525 GeV

m( 1)=0 GeV

t1

t

1(medium), t1→t

1

χ˜±

χ˜0

χ˜±

χ˜0

o

  • r
  • .

neg

˜ ˜

  • 0
  • 2 b

1 b 2 b

150-580 GeV 200-610 GeV
320-660 GeV

t1

t

1(medium), t1→b

m( 1)<200 GeV, m( 1 )-m( 1)=5 GeV

1

p

χ˜0 χ˜0

1 e, µ

χ˜0

  • ˜ ˜
  • ˜

˜

ATLAS-CONF-2013-037 ATLAS-CONF-2013-024 ATLAS-CONF-2013-068 ATLAS-CONF-2013-025 ATLAS-CONF-2013-025

tc

m( 1)=0 GeV

t1

t

1(heavy), t1→t

1χ˜0

˜ ˜

0

m( 1)=0 GeV

χ˜0

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t1

t

1(heavy), t1→t

1

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χ˜0

mono-jet/c-tag

˜

˜

t1

˜

t1

˜

t2

  • ˜ ˜
  • ˜

0

90-200 GeV

m(t1)-m( 1)<85 GeV

t1

tt1, t1→c

d

1

˜ ˜

χ˜0

2 e, µ (Z) 3 e, µ (Z) t1 1(natural GMSB)

500 GeV
271-520 GeV

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    Search for long-lived supersymmetry in final states with jets and missing energy in the CMS detector Christian Laner Ogilvy Imperial College London Department of Physics A thesis submitted to Imperial College London for the degree of Doctor of Philosophy ii Abstract An inclusive search for supersymmetry in final states with jets and missing transverse momentum is performed in proton-proton col- lisions at a centre-of-mass energy of 13 TeV. A data sample with an 1 integrated luminosity of 35.9 fb− recorded by the CMS detector in 2016 at the CERN LHC is analysed. The observed signal candidate event counts are found to be in agreement with the standard model expectation. Within the context of simplified models, the masses of promptly decaying bottom, top and mass-degenerate light-flavour squarks are excluded at 95% confidence level up to 1050, 1000 and 1325 GeV, respectively. The gluino mass is excluded up to 1900, 1650 and 1650 GeV for a gluino decaying promptly via the afore- mentioned squarks. The result is also interpreted in the context of simplified models of split supersymmetry. Lower limits are placed on the mass of a long-lived gluino for a wide range of lifetimes. Gluino masses up to 1750 and 900 GeV are excluded for gluinos with a lifetime of 1 mm and metastable gluinos, respectively. These results provide complementary coverage to dedicated searches for long-lived particles at the LHC. iii Declaration I declare that this thesis is the result of my own work. All work produced by others is referenced appropriately.
  • Albert, A., Bauer, M., Brooke, J., Buchmueller, O., Cerdeno, D. G., Citron, M., Davies, G., Cosa, A

    Albert, A., Bauer, M., Brooke, J., Buchmueller, O., Cerdeno, D. G., Citron, M., Davies, G., Cosa, A

    Albert, A., Bauer, M., Brooke, J., Buchmueller, O., Cerdeno, D. G., Citron, M., Davies, G., Cosa, A. D., Roeck, A. D., Simone, A. D., Pree, T. D., Ellis, J., Flaecher, H., Fairbairn, M., Ellis, J., Grohsjean, A., Hahn, K., Haisch, U., Harris, P. C., ... Wardle, N. (2017). Towards the next generation of simplified Dark Matter models. Physics of the Dark Universe, 16, 49-70. https://doi.org/10.1016/j.dark.2017.02.002 Peer reviewed version License (if available): CC BY-NC-ND Link to published version (if available): 10.1016/j.dark.2017.02.002 Link to publication record in Explore Bristol Research PDF-document This is the author accepted manuscript (AAM). The final published version (version of record) is available online via Elsevier at http://www.sciencedirect.com/science/article/pii/S2212686417300079. Please refer to any applicable terms of use of the publisher. University of Bristol - Explore Bristol Research General rights This document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/red/research-policy/pure/user-guides/ebr-terms/ Towards the next generation of simplified Dark Matter models Andreas Albert,1 Martin Bauer,2 Jim Brooke,3 Oliver Buchmueller,4 David G. Cerde˜no,5 Matthew Citron,3 Gavin Davies,3 Annapaola de Cosa,6 Albert De Roeck,7,8 Andrea De Simone,9 Tristan Du Pree,7 Henning Flaecher,4 Malcolm Fairbairn,10 John Ellis,10,11 Alexander Grohsjean,12 Kristian Hahn,13 Ulrich Haisch,10,14 Philip C.
  • Search for a Supersymmetric Higgs Boson Using Multilepton Signatures with the CMS Detector at the Large Hadron Collider

    Search for a Supersymmetric Higgs Boson Using Multilepton Signatures with the CMS Detector at the Large Hadron Collider

    Search for a Supersymmetric Higgs Boson using Multilepton Signatures with the CMS Detector at the Large Hadron Collider Department of Physics Graduate School, Chonnam National University Kim, Zero Jaeho A dissertation submitted in partial fulfillment of the reuirements for the degree of Doctor of Philosophy in Physics August 2013 \Let there be light", and there was light Genesis 1:3, the Hole Bible Abstract Search for a Supersymmetric Higgs Boson using Multilepton Signatures with the CMS Detector at the Large Hadron Collider Kim, Zero Jaeho Department of Physics Graduate School, Chonnam National University (Supervised by Professor Jae Yool Kim) p A search for supersymmetric higgs boson in proton-proton collisions at s = 8 TeV is presented, focusing on events with three and four leptons and large missing energy. The analyzed data corresponds to a total integrated luminosity of 19.5 fb−1 recorded by the CMS detector. The search uses a fully data-driven method to estimates residual Standard Model backgrounds. The analysis is performed on both of the channel of µµ+µ(e) and µµ+µµ(ee), The observed event rates are in agreement with expectations from the standard model. The results are used to set limits on the direct production of charginos, neutralinos, and sleptons in terms of limits on the parameter space, as well as a Simplified Model and Gauge Mediated Supersymmetry Breaking model. And the GMSB models with region of mass parameter µ between 330 and 370 for µµ + µ and over 310 for µµ + e channel, which has the theoretical cross section out of the 95% C.L expected limit with two standard deviation, is proposed to check across with relevant study repeatedly.
  • Pdfs Parton Distribution Functions SD Spin-Dependent SI Spin-Independent SM Standard Model (Of Particle Physics) Super-K Super-Kamiokande Xxiv

    Pdfs Parton Distribution Functions SD Spin-Dependent SI Spin-Independent SM Standard Model (Of Particle Physics) Super-K Super-Kamiokande Xxiv

    University of Melbourne Doctoral Thesis Phenomenology of Particle Dark Matter by Rebecca Kate Leane ORCID: 0000-0002-1287-8780 A thesis submitted in fulfillment of the requirements for the degree of Doctor of Philosophy in the School of Physics Faculty of Science University of Melbourne May 5, 2017 iii Declaration of Authorship I, Rebecca Kate Leane, declare that this thesis: • comprises only my own original work, except where indicated in the preface, • was done wholly while in candidature; • gives due acknowledgement in the text to all other materials consulted; • and is fewer than 100,000 words in length, exclusive of Tables, Figures, Bib- liographies, or Appendices. Signed: Date: v “I was just so interested in what I was doing I could hardly wait to get up in the morning and get at it. One of my friends said I was a child, because only children can’t wait to get up in the morning to get at what they want to do.” – Barbara McClintock (Nobel Prize in Medicine) vii Abstract The fundamental nature of dark matter (DM) remains unknown. In this thesis, we explore new ways to probe properties of particle DM across different phe- nomenological settings. In the first part of this thesis, we overview evidence, candidates and searches for DM. In the second part of this thesis, we focus on model building and signals for DM searches at the Large Hadron Collider (LHC). Specifically, in Chapter 2, the use of effective field theories (EFTs) for DM at the LHC is explored. We show that many widely used EFTs are not gauge invariant, and how, in the context of the mono-W signal, their use can lead to unphysical signals at the LHC.
  • Interplay and Characterization of Dark Matter Searches at Colliders and in Direct Detection Experiments

    Interplay and Characterization of Dark Matter Searches at Colliders and in Direct Detection Experiments

    Interplay and Characterization of Dark Matter Searches at Colliders and in Direct Detection Experiments Sarah A. Malik,a Christopher McCabe,b;c Henrique Araujo,a Alexander Belyaev,d;e C´elineBœhm,b Jim Brooke,f Oliver Buchmueller,a Gavin Davies,a Albert De Roeck,g;h Kees de Vries,a Matthew J. Dolan,i John Ellis,g;j Malcolm Fairbairn,j Henning Flaecher,f Loukas Gouskos,k Valentin V. Khoze,b Greg Landsberg,l Dave Newbold,f Michele Papucci,m Timothy Sumner,a Marc Thomasd;e and Steven Worme aHigh Energy Physics Group, Blackett Laboratory, Imperial College, Prince Consort Road, London, SW7 2AZ, UK bInstitute for Particle Physics Phenomenology, Durham University, Durham, DH1 3LE, UK cGRAPPA, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands dSchool of Physics and Astronomy, University of Southampton, Highfield, Southampton, SO17 1BJ, UK eParticle Physics Department, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, UK f HH Wills Physics Laboratory, Tyndall Avenue, Bristol, BS8 1TL, UK gPhysics Department, CERN, CH1211 Gen`eve23, Switzerland hAntwerp University, B2610 Wilrijk, Belgium iTheory Group, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA jTheoretical Particle Physics and Cosmology Group, Department of Physics, King's College Lon- don, London, WC2R 2LS, UK kUniversity of California, Santa Barbara, Department of Physics Broida Hall, Bldg. 572, Santa Barbara, CA 93106-9530, USA lPhysics Department, Brown University, Providence, Rhode Island 02912, USA mLawrence Berkeley National Laboratory, Berkeley, CA 94720, USA Abstract: In this White Paper we present and discuss a concrete proposal for the consis- tent interpretation of Dark Matter searches at colliders and in direct detection experiments.
  • Job Description

    Job Description

    Job Description Job Description Job Title: Research Associate AION Project Department/Division/Faculty: High Energy Physics, Department of Physics, Faculty of Natural Sciences Campus location: South Kensington Campus with regular travel throughout the United Kingdom, and international travel Job Family/Level: Research Family, Research Associate* Responsible to: Professor Oliver Buchmueller, Professor of Physics Key Working Relationships: Academic staff, Research Associates, PhD students, (internal) Mechanical and Electronic Engineers) Key Working Relationships Members of the AION collaboration (external) Contract type: Full-time, Fixed-term post for two years in the first instance, with the possibility of extension dependent on future funding. Purpose of the Post • The primary focus will be on the novel Atom Interferometer Observatory and Network (AION) project (website, paper), where the group has major responsibilities in building a new Ultracold Strontium Laboratory at Imperial and to perform essential research and development of the underlying Strontium atom interferometry. The AION project was recently funded by EPSRC and STFC via the Quantum Technology for Fundamental Science (QTFP) call. This programme will deliver deployable quantum technology to study dark matter and gravitational waves by constructing 10m and 100m scale instruments, paving the way for a km-scale facility, and eventually a spaced based detector. The institutions involved in AION are: University of Birmingham, University of Cambridge, Imperial College London (lead), Kings College London, University of Liverpool, University of Oxford, and STFC Rutherford Appleton Laboratory, In addition, the project is in partnership with UK National Quantum Technology Hub in Sensors and Timing, Birmingham, UK, the MAGIS Collaboration, US and the Fermi National Accelerator Laboratory, US.