Thursday, 6th of July

Location: 21 Wally’s Walk, Rm 2.300

Facilitators: Lara Sharp, James Murray & Jackie Bondell

In this session, the EPOC team will engage participants in a series of hands-on activities to activate their innovative design skills, review best practices for Astronomy outreach, and create a low-tech demo/activity to use on their outreach endeavours!

Location: Rm 163, ground floor

Zoom link:  https://macquarie.zoom.us/j/87986414345

Facilitator: Paul Hancock

This short course of three sequential and connected workshops will use Google Colaboratory and scikit learn to understand how to "do ML" with some astronomy-relevant data sets. Attendance of all three sessions (one per day) is required.

** This session has reached capacity for in-person attendance. 

Location: Mason theatre, ground floor

Zoom link: https://macquarie.zoom.us/j/82321436522

Slack channel: #asa2023-mw-localuniverse

Chair: Anita Hafner, Co-Chair: Jayender Kumar

11:00am: Chemistry as a Tracer of the Milky Way's Assembly History - Daniel Zucker, Macquarie University

Chemistry -- in the form of stellar spectroscopic abundances -- provides a key parameter space for tracing the assembly history of the Milky Way. Using abundance information we can infer some of the properties of the progenitors of stellar streams and structures, as well as distinguish between the remnants of ""true"" Milky Way mergers (e.g., Gaia-Sausage-Enceladus) and dynamical structures composed of stars likely born in-situ (e.g., Nyx). I will discuss how abundance data from two ongoing Australian-led surveys -- GALAH and S5 --  are being used for understanding the nature of stellar streams and phase-space-resolved stellar overdensities, as well as identifying discrete accretion events, and will also explore some of the limitations that confront us as we try to apply chemistry to deciphering the Galaxy's complex history. 

11:15am: Who is In, and Who is Not? Determining the Gaia Survey Selection Function - Alfred Castro Ginard, Leiden Observatory/Monash University

What is the probability that an astronomical object of certain properties enters the Gaia catalogue (or not)? The GaiaUnlimited project aims to enable the full potential of Gaia by characterising its survey selection function, as well as for different subsamples of the data, which are key ingredients in most statistical studies of the Milky Way. By comparing Gaia with deeper imaging from the Dark Energy Camera Plane Survey (DECaPS), we have developed an empirical model of the completeness in the Gaia pipeline, as a function only of the observed G magnitude and position over the sky, which accounts for both the effects of crowding and the complex Gaia scanning law. We also demonstrate the recipe to estimate the selection function of the stars present in a subsample of Gaia data, given that the subsample is completely contained in the Gaia parent catalogue, and how it can be extended to include the selection functions of other surveys (e.g. WEAVE, GALAH). Finally, we demonstrate the use of these selection functions by showing that the asymmetry in the Gaia-Sausage/Enceladus debris is merely due to selection effects.

11:30am: Mg isotope ratios reveal the accreted component of the Milky Way - Madeleine McKenzie*, ANU

The question of how galaxies form and evolve across cosmic time is central to Australian astronomy. In the context of lambda CDM cosmology and hierarchical assembly structure formation, dwarf galaxies are the closest existing analogues to high redshift proto-galaxies that merged to form our Milky Way (MW). Serving as unique laboratories for studying stellar nucleosynthesis, the elemental abundances of stars from dwarf galaxies play a pivotal role in constraining their chemical enrichment history. The discovery of a high- and low-alpha sequence revolutionised our understanding of the assembly history of the MW, with low [alpha/Fe] stars representing the accreted component of the MW, such as Sequoia and Gaia-Sausage-Enceladus. To date, almost all studies of dwarf galaxies and halo substructure have focused exclusively on element abundance ratios. Nucleosynthesis, however, operates on the isotopic level. In this talk, I will discuss how Mg isotope ratios have the power to unveil accreted dwarf galaxy stars in a way that has never been explored before and reveal details of SNeII or AGB contributions that cannot be discerned from element abundances alone.

11:45am: Magnetic fields in the turbulent, multiphase interstellar medium - Amit Seta, ANU

Magnetic fields are a dynamically important component of the interstellar medium (ISM) of star-forming galaxies. The ISM is turbulent due to several driving mechanisms (i.e., supernova explosions and gravitational instabilities), and this turbulence amplifies and maintains magnetic fields in the ISM via the turbulent dynamo (i.e., the process of converting turbulent kinetic energy to magnetic energy). Furthermore, the ISM is multiphase due to various heating and cooling processes. The properties of turbulence and, by extension, magnetic fields differ with the ISM phase. The talk will discuss some of the theoretical, observational, and numerical aspects of magnetic fields and turbulent dynamo in the multiphase ISM.

12:00pm: CN and CO Features: Key Indicators of Red Giant Evolutionary Phase - Kirsten Banks*, UNSW/ASTRO-3D

Data-driven analysis can infer physical properties of red giant stars from spectroscopy when asteroseismic data are not available. By analysing optical and infrared spectra, we can derive asteroseismic quantities, which indicate a star’s evolutionary phase. This enables us to distinguish red clump (RC) stars, which are standard candles, from first-ascent red giant branch (RGB) stars that are not. This allows large spectroscopic surveys to identify RC stars with minimal RGB contamination which can benefit Galactic archaeology studies investigating the chemodynamical structure of the Milky Way. I will present recent results confirming that CN and CO features are effective spectroscopic indicators of red giant evolution. This work uses 49 red giant stars with moderate-resolution VLT/X-Shooter spectra to build on previous work by Hawkins et al. (2018), expanding the wavelength range tenfold, covering both the optical and near-infrared. The Cannon was utilised to generate a spectral model, trained on the spectra of 49 stars with stellar and asteroseismic labels sourced from the GALAH survey and K2 mission respectively, that revealed which spectroscopic features most effectively encode red giant evolution. 

Poster sparklers in this session:

P1: Andrew Cameron, Swinburne 

P8: Lachlan Marnoch*, Macquarie University

P15: Yuzhe Song, Swinburne 

P54: Justin Clancy*, University of Melbourne

Location: T2, second floor

Zoom link: https://macquarie.zoom.us/j/81099211834

Slack channel: #asa2023-pulsars

Chair: Adelle Goodwin, Co-Chair: Alma Sebastian

11:00am: Long-period radio transients - Natasha Hurley-Walker†, Curtin Uni./ICRAR

SKA pathfinder instruments are probing the radio sky in new ways, searching the sky on timescales hitherto unexplored. Sensitive image-plane surveys are discovering new kinds of radio transients, with unusual temporal, spectral, and polarisation properties. Two intriguing periodic transients were published last year: a pulsar-like object repeating every 76s that is growing fainter with time (Caleb et al. 2022), and a short-lived radio transient repeating every 18 minutes (Hurley-Walker et al. 2022a). Both are potential examples of  “ultra-long period” (ULP) magnetars, and their radio emission might be explained by a temporary twisting and/or reorganisation of their intense magnetic fields. These discoveries are spurring new searches for similar long-period sources. Last year we conducted a transient imaging survey of the Galactic plane with the MWA at 200 MHz. We were successful in detecting a further long-period transient, which compared to previous examples shows different pulse morphologies, polarisation behaviour, and a staggeringly different activity window. Timing estimates place the source  below the conventional “death lines” of emission mechanisms that explain radio emission in neutron stars. These sources are just the tip of the iceberg of a new population, the exploration of which will illuminate the behaviour of neutron stars and therefore physics in extreme environments. I will conclude the talk with future survey plans across a range of telescopes.

11:15am: Interstellar scintillation of the Double Pulsar using MeerKAT  - Jacob Askew*, Swinburne/OzGrav

One of the most important astrophysical objects is the double pulsar. The short 2.5-hour orbital period and the presence of two neutron-stars observed as radio pulsars has enabled some of the most stringent tests of relativistic gravity and has the potential to probe nuclear equations of state. However, to make more precise tests, it is necessary to improve on the distance measurement. The distance to the system has been measured using very long baseline interferometry and through pulsar timing. There is growing evidence of systematic discrepancies between the two measurements. It is possible to measure the distance independently using interstellar scintillation: the interference the pulsar radiation experiences caused by the turbulent interstellar medium. Here we present a scintillation analysis of the double pulsar from a year-long campaign with the MeerKAT radio telescope. We present a model for the interstellar medium along the line of sight to the pulsar.  We use this model to infer an independent distance to the pulsar.  We then outline systematic effects that can be impacting all three distance measurements. We conclude by discussing how revised distance estimates will impact future tests of relativity with the system.

11:30am: Rocks around the clock? A case study of pulsar-asteroid interactions with PSR J0738-4042 - Marcus Lower, CSIRO

Long-term pulsar monitoring projects have begun to uncover a growing population of variable pulsars that display correlated changes in their spin-down rates and pulse profile shapes. Some of this behaviour may result from these pulsars interacting with the in-falling asteroids. In this talk I will present a comprehensive case study on PSR J0738-4042, one of the most well-known transient spin-down/shape changing pulsars. Using an expanded, 50-year dataset, we constructed continuous models for the spin-down and profile shape evolution of this pulsar. Curiously, we found the pulsar failed to exhibit a substantial change in spin-down in coincidence with a previously under-reported shut-down of a bright profile component. We discuss the challenges these observations pose for physical models for generating such behaviour and conclude that interactions between the pulsar and in-falling asteroids remains the most likely explanation.

11:45am: The CRAFT FRB surveys: recent results and the value of commensality - Marcin Glowacki, Curtin Uni./ICRAR

The Australian Square Kilometre Array Pathfinder (ASKAP) is one of the leading fast radio burst (FRB) detection and localisation telescopes. On behalf of the Commensal Real-time ASKAP Fast Transients (CRAFT) Survey team I will present an update on work from the past year. Localisations of FRBs to their host galaxies with <1 arcsecond precision have been steadily increasing. Our FRB localisations have been used to constrain the Hubble Constant, and with high time resolution (3 ns) data analysis investigate scattering screen models of the FRB signal. I will present our latest sample of FRBs and host galaxies, combined with dedicated optical imaging and spectroscopic follow-up often the ESO VLT. I also highlight the value of CRAFT being a commensal survey, where in collaboration with the Widefield ASKAP L-band Legacy All-sky Blind surveY (WALLABY) we made the first commensal detection of an FRB and neutral hydrogen (HI) emission within the same host galaxy - only the fourth published detection of HI gas in an FRB host galaxy. 

12:00pm: The first Fast Radio Burst at a redshift of 1 - Stuart Ryder, Macquarie Uni./AAL

Fast Radio Bursts (FRBs) have incredible potential as cosmological probes, but only if they can be detected and localised to galaxies at redshifts above 1. We present FRB 20220610A discovered with ASKAP, and confirmed with X-shooter on the ESO VLT to have originated from a host galaxy system at a redshift just above 1, almost twice as far as any known FRB. The high burst energy confirms the presence of an energetic burst population at high redshift, and bodes well for ASKAP+CRACO and eventually SKA to discover FRBs at cosmologically-interesting redshifts.

Poster sparklers in this session:

P1: Andrew Cameron, Swinburne 

P8: Lachlan Marnoch*, Macquarie University

P15: Yuzhe Song, Swinburne 

P54: Justin Clancy*, University of Melbourne

Location: Mason theatre, ground floor

Zoom link: https://macquarie.zoom.us/j/82321436522

Slack channel: #asa2023-facilities-surveys-outreach

Chair: Kirsten Banks, Co-Chair: Ben Montet

2:30pm: SkyMapper Southern Survey - Data Release 4 - Christopher Onken†, ANU

We present the fourth data release from the SkyMapper Southern Survey (SMSS). Covering the full Southern hemisphere in 6 optical filters, with half a million images acquired over more than 7 years, DR4 increases the survey's area of deep sky coverage and improves its photometric quality by calibrating to synthetic photometry from Gaia's low-resolution spectra. SMSS DR4 is being made available to astronomers worldwide to support research stretching from Solar System objects to high-redshift quasars. We will describe the enhancements in DR4 and demonstrate the data access tools of the SkyMapper node of the All-Sky Virtual Observatory.

2:45pm: The Rapid ASKAP Continuum Survey - Stefan Duchesne†, CSIRO

Surveys of the sky at myriad wavelengths provide a view into the large-scale properties of the Universe while also allowing studies of individual and sometimes unique astrophysical objects and processes. The Australian SKA Pathfinder (ASKAP) is completing a series of shallow radio-frequency surveys as part of the Rapid ASKAP Continuum Survey” (RACS). RACS covers three radio-frequency bands centered on 888, 1367, and 1632 MHz and covers the whole sky up to declination +48 degrees. RACS provides a combination of frequency, sensitivity (~ 150-300 micro Jansky/beam), and resolution (~8-15 arcsec) that fills a niche in the existing ecosystem of all-sky surveys. Imaging and catalogue releases are underway and focus on the continuum total intensity and circularly polarized emission of the sky accessible to ASKAP, featuring >3M radio sources in each of the three bands. As well as this continuum component, spectro-polarimetric work in linear polarization is also underway. On behalf of the team behind RACS, I will describe the surveys, highlight a selection of science results so far, and report on the progress of RACS. 

3:00pm: SDSS-V: The fifth generation of the Sloan Digital Sky Survey - Andrew Casey, Monash University

The Sloan Digital Sky Survey is one of the most successful astrophysics experiments, with nearly 20 public data releases made over 23 years. The fifth generation of SDSS is now acquiring multi-epoch optical and infrared spectroscopy across the entire sky, as well as contiguous integral-field unit spectroscopy of the Milky Way and local volume galaxies. These data address the three mapper programs of SDSS-V: (1) the Black Hole Mapper will explore the growth of black holes in the universe; (2) the Milky Way Mapper will comprehensively map stars and dust in our galaxy's disk, and (3); the Local Volume Mapper will contiguously map the local bubble with integral-field unit spectra. This data volume will exceed previous generations of SDSS by orders of magnitude, and is only realisable with new telescopes, new fibre-fed positioning systems, and new approaches to data analysis and calibration. The science goals of SDSS-V -- and the technologies used to achieve them -- have strong overlap with Australian astronomy, and there are opportunities for Australia to continue to make key contributions. In this talk I will present a first look at the new scientific discoveries of SDSS-V, as well as the telescopes, instruments, and software that underpins that science.

3:15pm: Balancing the Equation: Representation of Scientists in High School Physics - Kathryn Ross, Curtin Uni./ICRAR

The visibility of female role models in science is vital for engaging and retaining women in scientific fields. Unfortunately, for many minorities in STEM, there is a lack of accessible and relatable role models, especially at critical career stages where students are considering potential career paths. In this talk, we present the results of a comprehensive content analysis of year 11 and year 12 Physics courses around Australia and the biased representation of scientists within them. In particular, this talk will discuss the problematic narrative of the “lone-male-genius” and the Eurocentric focus of all content and their implications for gender diverse and minority students. Lastly, this talk will outline possible solutions to address this issue, including the accreditation of scientific discoveries to include female scientists and explicit discussion of structural barriers preventing the participation and progression of women in STEM and the role research institutes and higher education will need to have in addressing these complex issues. 

3:30pm: Motivating students in an online astronomy course - Kate Jackson, UNSW

Student motivation is a perennial problem in all stages of education. Most students find astronomy a fascinating and intriguing topic, but even in tertiary astronomy courses, it can be a struggle to maintain student motivation. Students are typically extrinsically motivated, often by grades and other rewards systems, but extensive research shows that intrinsic motivation leads to more positive outcomes, such as a growth mindset, better grades, lower academic misconduct, and more fulfilment in goals and achievements. To reduce instances of academic dishonesty, students must be intrinsically motivated to learn, which can be fostered through increasing students' feelings of competence and autonomy (i.e., by allowing greater freedom of choice and creativity). Using imagery has also been shown to increase non-science students’ motivations and understanding of scientific concepts. By designing courses and assessments that use imagery, give students choice, and allow for creativity, students’ intrinsic motivation should increase. This presentation focuses on the approach and development of the learning activities in a wholly online introductory astronomy course and highlights simple evidence-based techniques that improve students’ intrinsic motivation.

3:45pm: SciX: Scalable and sustainable authentic research experiences for high-school students - Laura McKemmish, UNSW

In NSW, the new Yr 12 HSC Science Extension course recommends students find university mentorship to support their individual research projects. The SciX high-school outreach program (unsw.to/scix) has been developed and refined to meet this demand in an equitable, sustainable, scalable, effective and quality-controlled way. SciX centres around an intensive one-week authentic research experience with online pre-work and post-summer-school Q&A sessions. High school students select a research area, such as astronomy or spectroscopy, and are placed in small groups led by SciX mentors, usually paid PhD candidates. Students are taught disciplinary research topics and tools then supported to develop their individual hypothesis and conduct their research. Surveys show students not only love the experience, but strongly increase their self-identification as a scientist and develop crucial transferable and scientific skills. Mentors develop important professional skills, e.g. in supervising, mentoring, teaching and management. Careful project design and program structure are crucial for delivering a high-quality, scalable experience with modest resources. As inspiration for how you might deliver short enriching research experiences for high-school or undergraduate students, I will describe how SciX has addressed key challenges to scale to more than 150 students (63% female) with 40% fee-waivers for low-SES and regional students."

Poster sparklers in this session:

P83: James Tocknell, AAO Macquarie

P85: Vanessa Moss, CSIRO

P88: Nian Jiang, Astralis

P89: Chris Lidman, ANU

Location: T2, second floor

Zoom link: https://macquarie.zoom.us/j/81099211834

Slack channel: #asa2023-data-pipelines

Chair: Simon O’Toole, Co-Chair: Saurav Mishra

2:30pm: Science Operations with the SKAO

- Shari Breen, SKAO (45 mins)

3:15pm: Data Central: from Data Archive to Science Platform - Elizabeth Davies, Macquarie Uni./AAO

The Data Central Science Platform has revolutionised how astronomical research teams manage projects across the full data lifecycle. Launched back in August 2017, Data Central has evolved rapidly over the past 6 years, from an optical data archive, to a fully-fledged Science Platform, enabling researchers to make key discoveries with their data across multiple domains. Data Central provides instant access to both cutting edge and legacy data across a breadth of national and international facilities and instruments. We provide user-focused exploration alongside complementary cross-matched data to facilitate new scientific discoveries. Users can run analyses, data reduction routines, and publish data to the world, all on a single platform; a crucial step forward in the era of big-data, where large data volumes are no longer manageable on desktop machines. Here we present the ecosystem as a whole, the current top-level services (data access, data processing and analysis, team management, cloud storage), a brief dive into the underbelly and the complexities faced when designing, deploying and scaling a Science Platform, services to be launched this year, and our future milestones. We’ll detail how you can access support and services from Data Central for your team, or scientific projects.

3:30pm: Build Your Own Adventure: Next Generation Applications Powered By Data Central - Brent Miszalski, AAO/Macquarie Uni.

Data Central has developed unique infrastructure that allows astronomers to build their own next generation web applications. Using modern Python web services it is now possible to replicate, in your web browser, many of the traditional astronomical workflows including data reduction pipeline execution, harvesting and aggregation of archival data, and data visualisation and analysis. In this talk we will present an overview of our current capabilities including the Data Aggregation Service (data harvesting for single sources from online services and archives), the Pipeline As a Web Service (PAWS) model for data reduction (automatic on demand reduction of archival data), and a Target Selection Service (efficient classification and interactive visualisation of images and catalogues for large target lists). Astronomers may engage Data Central via the Astronomy Data And Computing Services (ADACS) Merit Allocation Program to collaboratively build their own next generation applications based upon our extensible infrastructure. Web applications may incorporate a mix of proprietary data (accessible only to designated teams) or publicly accessible data hosted by Data Central or elsewhere.

3:45pm: Australia's multi-faceted contributions to ESO's VLT data reduction pipelines: improvements, innovations, and future initiatives - Nuria Lorente, AAO, Macquarie Uni.

The ESO Pipelines project brings together decades of expertise from AAO Macquarie and ANU Stromlo in the field of innovative algorithms, data, and software engineering, for the development and maintenance of pipeline data reduction software for 21 ESO VLT instruments. In this talk we will present highlights of the last 4 yrs of data reduction improvements, and discuss the innovations we are working on with ESO as part of the EDPS system rollout which will underpin operational and user data reduction in the ELT era. Finally we will share how you can access ESO’s powerful CPL library - the backbone of ESO pipelines - through python, to easily write your own data manipulation scripts and prototypes.

Poster sparklers in this session:

P83: James Tocknell, AAO Macquarie

P85: Vanessa Moss, CSIRO

P88: Nian Jiang, Astralis

P89: Chris Lidman, ANU