2023 CDM Annual Workshop

7:00-9:00

Breakfast (for those staying the night before)

Promenade Restaurant

8:30-9:00

30

Registration (for those not registered on previous days)

Function foyer (outside Ballrooms)

9:00-9:10

10

Welcome to Country

Uncle Rod

9:10-9:30

20

Welcome from Director and housekeeping

Elisabetta Barberio / Anita Vecchies

Session 1

Session Chair - Tony Williams

Ballrooms 1 + 2

9:30-10:00

30

Keynote presentation - Status and prospects of underground Direct Detection experiments

Marc Schumann

The direct detection of dark matter particles scattering off a laboratory target is a way to probe the dark matter around us. I will briefly review the current status of the field and what is required to cover the entire accessible parameter space before irreducible neutrino backgrounds limit the detection sensitivity.

10:00-10:30

30

Keynote presentation - LHC summary talk

Paul Jackson

The ATLAS experiment at the Large Hadron Collider (LHC) is one of the most powerful tools in the search for dark matter. Dark matter is a mysterious substance that makes up about 85% of the matter in the universe, but it cannot be directly observed because it does not interact with light or other forms of electromagnetic radiation. However, dark matter does interact with ordinary matter through gravity, and this interaction can be indirectly detected by the ATLAS experiment.

One way that ATLAS searches for dark matter is by looking for events with large missing transverse momentum. Missing transverse momentum is a measure of the amount of momentum that is missing from an event. If dark matter particles are produced in a collision at the LHC, they will escape the detector without interacting with it, leaving behind a signature of missing transverse momentum. ATLAS has also conducted searches for dark matter by looking for decays of the Higgs boson into invisible particles and other invisible signatures. If the Higgs boson can decay into dark matter particles, it would provide a direct link between dark matter and the Standard Model of particle physics. To date, ATLAS has not found any definitive evidence for dark matter. However, the experiment has placed important constraints on the properties of dark matter particles. These constraints have helped to guide the development of new theories of dark matter, and they will continue to be important as the search for dark matter continues.

This talk will cover the contributions to searches being made by Centre researchers and discuss our efforts in work to upgrade the detector for future higher energy and intensity collisions at the LHC.

10:30-11:00

30

Icebreaker activity

Anita Vecchies

This will be a group activity on each table. We will ask the room a simple question and give each table a few minutes to discuss their answers. Then half the table (every second person) gets up and swaps to another table where you will answer the next question. And repeat until we have run out of time. The questions will be light (eg. What’s your favourite beverage?) and some with a bit of a physics focus (eg. what’s your favourite equation) it’s not mandatory for everyone on the table to answer every question.

11:00-11:30

30 min

Morning Tea

Function foyer (outside Ballrooms)

Session 2

Session Chair - Irene Bolognino

Ballrooms 1 + 2

11:30-12:00

30

Keynote presentation - Theory summary talk - Astroparticle

Celine Boehm

12:00-13:00

60

EDI training session - Part 1 - Neurodiversity presentation - Supporting a neurodiverse workforce

Ash Vance and Chris Ferguson from Untapped Talent

13:00-14:00

60 min

Lunch

Function foyer (outside Ballrooms)

Session 3

Session Chair - Celine Boehm

Ballrooms 1 + 2

14:00-15:00

60

EDI training session - Part 2 - Neurodiversity workshop

Facilitated by Ash Vance and Chris Ferguson from Untapped Talent

15:00-15:15

15

Impact of nuclear structure on nuclear responses to WIMP elastic scattering

Raghda Abdel Khaleq

We build on previous work by investigating the sensitivity of nuclear response functions to nuclear structure for WIMP-nucleus elastic scattering, employing nuclear shell model interactions which differ from those used in previous literature to facilitate comparison between different nuclear structure results. This is performed for isotopes relevant to direct detection experiments:19F , 23Na, 28−30Si, 40Ar, 127I, 70,72−74,76Ge and 128−132,134,136Xe. Our integrated nuclear response values sometimes exhibit large (up to orders-of-magnitude) factor differences compared to those in previous works for certain WIMP-nucleus interaction channels and their associated isotopes. We highlight potential nuclear modelling uncertainties in WIMP-nucleus scattering amplitudes, and deduce the effect of these uncertainties on the scattering cross-sections associated with the XENON100 and LUX direct detection experiments for natXe isotopes.

15:15-15:30

15

Probing dark matter with gravitational waves

Giovanni Tomaselli

Future gravitational wave detectors will enable precision studies of black hole environments. Possible scenarios include: accretion disks, dark matter overdensities, or superradiant clouds of ultralight bosons. I will show how these environments alter the gravitational waveform, and how their characteristic imprint can allow us to identify them. I will then focus on the case of a cloud of ultralight bosons, discussing its properties, as well as its extremely peculiar gravitational wave signatures.

15:30-16:00

30 min

Afternoon Tea

Function foyer (outside Ballrooms)

Session 4

Session Chair - Theresa Fruth

Ballrooms 1 + 2

16:00-16:15

15

Dark Galaxies in the WALLABY survey

Jeremy Mould

WALLABY is a survey of the southern hemisphere in neutral hydrogen with the Australian Square Kilometre Array Pathfinder. In the pilot survey we are finding that 1% of the detected galaxies have no optical counterpart. Dark matter inferred from the velocity field of the gas is the main component of these galaxies.

16:15-16:30

15

Improving ATLAS Hadronic Object Performance with ML/AI Algorithms

Albert Kong

Experimental uncertainties related to hadronic object reconstruction can limit the precision of physics analyses at the LHC, and so improvements in performance have the potential to broadly increase the impact of results. Hadronic object reconstruction is also one of the most promising settings for cutting-edge machine learning and artificial intelligence algorithms at the LHC. Recent refinements to reconstruction and calibration procedures for ATLAS jets and MET result in reduced uncertainties, improved pileup stability and other performance gains. In this contribution, selected highlights of these developments will be presented.

16:30-16:45

15

First science run results of XENONnT

Yajing Xing

The XENONnT experiment, situated at the Laboratori Nazionali del Gran Sasso in Italy, is a leading experiment in the search for Dark Matter (DM). With its 5.9-tonne liquid xenon time projection chamber, this experiment seeks to detect weakly-interacting massive particles (WIMPs) as the primary objective. Having achieved unprecedented purity and background level, it opens the door to exploring various other rare signals, such as solar axions, axion-like particles, bosonic dark matter, and even solar neutrinos. This talk will provide an overview of the XENONnT detector, its performance, and the key findings from its first science run.

16:45-17:00

15

Exploring light dark matter with the Migdal effect in hydrogen-doped liquid xenon

Alexander Ritter

An ongoing challenge in dark matter direct detection is to improve the sensitivity to light dark matter in the MeV-GeV mass range. One proposal is to dope a liquid noble-element direct detection experiment with a lighter element such as hydrogen, while another avenue is to exploit the Migdal effect, where a nuclear recoil leads to electronic ionisation or excitation. Combining these ideas we find that current and future liquid-xenon detectors doped with hydrogen could have sensitivity to dark matter masses as low as 5 MeV. Notably, this technique substantially enhances the sensitivity of direct detection to spin-dependent proton scattering, well beyond the reach of any current experiments.

17:00-17:10

10

Group photo

Assemble on lawn outside the Stamford Grand

17:10-1830

80 min

Poster Session - platters provided

There will be a cash bar at the session where people can purchase their own drinks

Ballroom 3

Full details here: 2023 CDM Annual Workshop Poster Session - (Public) ARC CoE for Dark Matter Particle Physics - Confluence (atlassian.net)

During the poster session, there will be a photographer in Ballroom 5 set up to take profile photos of any Centre members that would like them. These will be provided to you after the workshop for you to use on the Centre website or LinkedIn etc.

There will also be a short opportunity to take some smaller group photos.

7:00-9:00

Breakfast (for those staying the night before)

Promenade Restaurant

8:30-9:00am

30

Registration (for those not registered on previous days)

Function foyer (outside Ballrooms)

Session 1

Session Chair - Sara Diglio

Ballrooms 1 + 2

9:00-9:30

30

Keynote presentation - Theory summary talk

Peter Cox

9:30-10:00

30

Keynote presentation - Metrology summary talk

Michaela Froehlich

Nuclear recoils induced by dark matter interactions typically have energies in a region heavily affected by environmental radioactive and cosmic background. Thus, metrology activities are largely focused on how to measure radioactivity in detector materials and the associated laboratory environment. This talk will focus on the most important radioactive species likely to impact detector capability, namely K-40, I-129 and Pb-210.

10:00-10;30

30

Keynote presentation - WISP/Axion summary talk

Michael Tobar

The axion is a putative particle that should exist to solve the strong CP problem in QCD, and if it exists can be calculated to be created in the early Universe and can account for all the perceived dark matter. The axion is predicted to interact with standard model particles allowing various avenues for detection. If axions interact with photons, Maxwell’s equations of electrodynamics are modified through the chiral anomaly g_{aγγ}, and solving these equations in various situations has allowed the determination of a variety of experimental techniques to search for axion dark matter. We will review how electrodynamics is modified, and show how to calculate the sensitivity of a variety of experiments over a variety of mass ranges.

More recently interactions between putative axions and magnetic monopoles have been revisited, in this case the axion-photon coupling parameter space is expanded from one parameter to three (g_{aγγ}, g_{aEM}, g_{aMM}), allowing new ways to search for axions and a possible indirect way to determine if magnetically charged matter exists. We propose to undertake new experiments during the life time of this Centre, giving a new opportunity for significant alternative searches for dark matter.

10:30-11:00

30

SABRE South update

Phillip Urquijo

The SABRE (Sodium iodide with Active Background REjection) experiment aims to detect an annual rate modulation from dark matter interactions in ultra-high purity NaI(Tl) crystals in order to provide a model independent test of the signal observed by DAMA/LIBRA. It is made up of two separate detectors; SABRE South located at the Stawell Underground Physics Laboratory (SUPL), in regional Victoria, Australia, and SABRE North at the Laboratori Nazionali del Gran Sasso (LNGS).

SABRE South is designed to disentangle seasonal or site-related effects from the dark matter-like modulated signal by using an active veto and muon detection system.  Ultra-high purity NaI(Tl) crystals are immersed in a linear alkyl benzene (LAB) based liquid scintillator veto, further surrounded by passive steel and polyethylene shielding and a plastic scintillator muon veto. Significant work has been undertaken to understand and mitigate the background processes, that take into account radiation from the detector materials, from both intrinsic and cosmogenic activated processes, and to understand the performance of both the crystal and veto systems. SABRE South will be assembled and commissioned in 2024/2025.

This talk will report the general status of SABRE South.

https://darkmatteraustralia.atlassian.net/wiki/download/attachments/1662681103/SABRE Annual Meeting.pdf?api=v2

11:00-11:30

30 min

Morning Tea

Function foyer (outside Ballrooms)

Session 2

Session Chair - Gary Hill

Ballrooms 1 + 2

11:30-12:00

30

DSTG priorities, projects, job opportunities and tips

Damian Marinaro

Damian will present a brief introduction to the Defence Science and Technology Group and provide insights on working with and for DSTG. Some of the research areas of interest to Defence will be outlined, intended as a primer to stimulate further discussion during and following the Workshop.

12:00-13:00

60

Mentoring activity - speed networking

Michaela Froehlich

The Speed Mentoring session will consist of 1:1 mentoring sessions for 5 min each and then the mentees will go to another mentor, so that they have the opportunity to talk to several mentors during this time.  

For this event, we would consider a mentee to be a student or an ECR. 

A mentor could be an ECR or a more senior person. Please fill out this form indicating whether you will participate as a mentor or mentee. 

https://forms.office.com/r/iVUk8WFy4E

13:00-14:00

60 min

Lunch

Collect a packed lunch from function foyer (outside Ballrooms) and you can eat it inside or take outside.

Session 3

Session Chair - Greg Lane

Ballrooms 1 + 2

14:00-14:15

15

Cosmic dust as a dark matter discriminator

Adam Ussing

Cold dark matter models explain the large-scale universe to a high degree of accuracy, but tensions with observations persist. Warm dark matter has been proposed as an alternative to cold dark matter to solve tensions. To test this we used cold and warm dark matter simulations with different stellar physics prescriptions and used the dust as our metric to probe the underlying dark matter model from an observational standpoint.

14:15-14:30

15

ORGAN Phase 1B: Results and Future Plans

Aaron Quiskamp

We report the results of Phase 1b of The ORGAN Experiment, a microwave cavity haloscope searching for dark matter axions in the 107.42−111.93 µeV mass range. The search excludes axions with two-photon coupling gaγγ ≥ 4 × 10^−12 GeV^−1 with 95% confidence interval, setting the best upper bound to date. This result was achieved using a tunable rectangular cavity, and was the first axion search to be conducted with such a cavity.

14:30-14:45

15

Luminous Proton Loops Thermalise Light Dark Matter

Joshua Wood

The DM-proton elastic scattering cross-section is a benchmark search for many direct detection experiments. Given a non-zero cross-section with protons, dark matter would necessarily interact with photons at one-loop. These one-loop interactions can thermalise light dark matter during BBN, violating bounds on the effective number of relativistic species at this time. We calculate and present novel limits on the DM-proton elastic scattering cross-section due to this effect.

14:45-15:00

15

Hide and Super-Seek: Searching for Displaced Vertices with Missing Transverse Energy at the ATLAS Detector

Emily Filmer

Supersymmetry is one proposed extension to the Standard Model. It has been difficult to search for experimentally, given its low interaction with SM particles, however higher collider energies and increased data collection at the ATLAS Detector allow us to probe new and promising areas of phase space. This talk will outline the search for Displaced Vertices at the ATLAS Detector, using Missing Transverse Energy. Building on a previous analysis, we use new vertexing methods and better understanding of the detector backgrounds to enhance our sensitivity to long-lived gluinos.

15:00-15:45

45 min

Afternoon Tea - EDI Committee meet and greet

Function foyer (outside Ballrooms)

Session 4

Session Chair - Andrew Stuchbery

Ballrooms 1 + 2

15:45-16:00

15

FlameNEST: powerful statistical inference for the LZ and XLZD experiments

Robert James

FlameNEST is a novel approach to statistical inference for liquid xenon time projection chambers that enables the incorporation of higher-dimensional observable spaces and correlated shape-varying nuisance parameters in a computationally efficient manner. It is currently being for statistical inference and detector calibration fits enabling dark matter searches with the world-leading LUX-ZEPLIN (LZ) experiment, as well as for sensitivity studies towards a next-generation liquid xenon experiment within the XLZD consortium. In this talk, the principles behind the framework are presented, and examples of its use for both LZ and XLZD are given. We highlight future activities for both projects and the role that FlameNEST will play in each.

16:00-16:15

15

Global QCD analysis and dark photons

Nicholas Hunt-Smith

We performed a global QCD analysis of high energy scattering data within the JAM Monte Carlo framework, including a coupling to a dark photon that augments the Standard Model (SM) electroweak coupling via kinetic mixing with the hypercharge B boson. We first set limits on the dark photon mass and mixing parameter assuming that the SM is the true theory of Nature, taking into account also the effect on g – 2 of the muon. If instead we entertain the possibility that the dark photon may play a role in deep-inelastic scattering (DIS), we find that the best fit is preferred over the SM at 6.5σ, even after accounting for missing higher order uncertainties. The improvement in χ2 with the dark photon is stable against all the tests we have applied, with the improvements in the theoretical predictions spread across a wide range of x and Q2. The largest improvement corresponds to the fixed target and HERA DIS data, while the best fit yields a value of g – 2 which significantly reduces the disagreement with the latest experimental determination.

16:15-16:30

15

The Twisted Anyon Cavity Resonator as a Potential Dark Matter Detector and Sensing Device

Emma Paterson

The minimum axion mass detectable by existing photonic dark matter searches is set by the detector's frequency and hence size, which places the lower limit around 10^(−7) eV, leaving the ultra-light dark matter (ULDM) parameter space relatively unexplored. In this work, a new class of electromagnetic resonator is described; the Anyon Cavity Resonator, which has the potential to couple to ULDM
axions. This is possible due to the existence of a single electromagnetic mode with non-zero helicity, which is generated in vacuo through a pure photonic magneto-electric coupling of a transverse electric (TE) and transverse magnetic (TM) mode. The resonator is based on twisted hollow structures that possess mirror asymmetry. The origin of these high helicity modes is demonstrated using finite element simulation. It is predicted that these cavities will have the capability to search for dark matter down to 10^(−24) eV with a minimum coupling strength of 10^(−15.8) GeV^(−1); covering a completely unexplored region of parameter space.

16:30-16:45

15

Advancing stellar constraints on weakly interacting slim particles

Fred Hiskens

Stellar evolution has historically provided some of the strongest constraints on weakly interacting slim particles (WISPs), a collection of non-thermal dark matter candidates characterised by their light masses and feeble interactions with the Standard Model. Recent improvements in observational and theoretical astrophysics, combined with known limitations for several existing bounds, offer new opportunities for advancing these limits. This talk focuses on two examples of such advancements, namely our use of the $R_2$ parameter of globular clusters to provide the strongest constraint on the axion-photon coupling in a wide range of parameter space, and our improvements on existing static limits on dark photons using simulations of globular cluster stars.

16:45-17:00

15

Search for new physics in final states with objects originating from a top-quark, a charm-quark and large EmissT in pp collisions at √s=13TeV

Tristan Ruggeri

A search for the pair-production of stops decaying to c-quark, top-quark and neutralinos is reported using a pp dataset with an integrated luminosity of 139 fb−1 collected with the ATLAS detector at √s=13TeV. The signal is searched for in events containing several energetic jets, of which at least one is c-tagged, large missing transverse momentum and no charged leptons. This search is motivated by non-minimal flavour violation extensions of the minimal supersymmetric standard model.

17:00

Close

18:30-21:30

Workshop Dinner and Awards

Ballrooms 3-4

21:30-12:00

Jiving at Jetty Bar

7:00-9:00

Breakfast (for those staying the night before)

Promenade Restaurant

Session 1

Session Chair - Matt Dolan

Ballrooms 1 + 2

9:00-9:30

30

Keynote presentation - Translation (XEMIS project)

Dominique Thers

In the context of the development of new technologies used for the Direct Search of Dark Matter with liquid xenon, my team at Subatech undertook the design of a Compton camera in order to initiate a potential widening of the impact of medical imaging. The project called XEMIS (XEnon Medical Imaging System) is based on an innovative instrument currently being installed at the Nantes University Hospital. During the workshop, I will present the motivations for this new technology, the targeted experimental results and also the main instrumental challenges. Scientific exploitation of the instrument and the first images are expected in 2024.

9:30-10:00

30

Keynote presentation - Collaborating wtih ANSTO

Richard Garrett

A brief overview of ANSTO will be given. ANSTO operates major national research infrastructure on behalf of the nation, notably the Australian Synchrotron, the Australian Centre for Neutron Scattering and the Centre for Accelerator Science. In addition, it applies nuclear science and technology in three main research areas: the Nuclear Fuel Cycle, the Environment, and Human Health. Accelerator science and technology are central to many of ANSTO’s facilities and research programs. Some thoughts on the direction of accelerator science and technology in Australia and internationally will be presented.

10:00-10:15

15

SUPL update

Sue Barrell

10:15-10:30

15

Outreach and Education update

Various on behalf of Jackie Bondell

10:30-11:00

30

Morning tea and Outreach Kit displays

Function foyer (outside Ballrooms)

Session 2

Session Chair - Jeremy Mould

Ballrooms 1 + 2

11:00-11:30

30

ECR updates and highlights from ECRs

ECR committee and various

11:30-12:00

30

Director wrap up and plans for 2024

Elisabetta Barberio

12:00-13:00

60

Lunch

Function foyer (outside Ballrooms)