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Calculation of Astrophysical Reaction Rate and Uncertainty for T(d,n)4He using Bayesian Statistical Approach Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-03-13 Seyyed Soheil Esmaeili, Abbas Ghasemizad, Omid Naserghodsi
One of the best methods to investigate and calculate a desired quantity using available limited data is the Bayesian statistical method, which has been recently entered the field of nuclear astrophysics and can be used to evaluate the astrophysical S-factors, the cross sections and, as a result, the nuclear reaction rates of Big Bang Nucleosynthesis. This study tries to calculate the astrophysical
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Are Odd Radio Circles phoenixes of powerful radio galaxies? Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-03-05 S. S. Shabala, P. M. Yates-Jones, L. A. Jerrim, R. J. Turner, M. G. H. Krause, R. P. Norris, B. S. Koribalski, M. Filipović, L. Rudnick, C. Power, R. M. Crocker
Odd Radio Circles (ORCs) are a class of low surface brightness, circular objects approximately one arcminute in diameter. ORCs were recently discovered in the Australian Square Kilometre Array Pathfinder (ASKAP) data, and subsequently confirmed with follow-up observations on other instruments, yet their origins remain uncertain. In this paper, we suggest that ORCs could be remnant lobes of powerful
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Early Accretion Onset in Long-Period Isolated Pulsars Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-02-27 M.D. Afonina, A.V. Biryukov, S.B. Popov
We model long-term magneto-rotational evolution of isolated neutron stars with long initial spin periods. This analysis is motivated by the recent discovery of young long-period neutron stars observed as periodic radio sources: PSR J0901-4046, GLEAM-X J1627-52, and GPM J1839-10. Our calculations demonstrate that for realistically rapid spin-down during the propeller stage isolated neutron stars with
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DARK SAGE: Next-generation semi-analytic galaxy evolution with multidimensional structure and minimal free parameters Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-02-27 Adam R. H. Stevens, Manodeep Sinha, Alexander Rohl, Mawson W. Sammons, Boryana Hadzhiyska, César Hernández-Aguayo, Lars Hernquist
After more than five years of development, we present a new version of Dark Sage, a semi-analytic model (SAM) of galaxy formation that breaks the mould for models of its kind. Included among the major changes is an overhauled treatment of stellar feedback that is derived from energy conservation, operates on local scales, affects gas gradually over time rather than instantaneously, and predicts a mass-loading
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EMU/GAMA: A Technique for Detecting Active Galactic Nuclei in Low Mass Systems Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-02-21 Jahang Prathap, Andrew M. Hopkins, Aaron S. G. Robotham, Sabine Bellstedt, José Afonso, Ummee T. Ahmed, Maciej Bilicki, Malcolm N. Bremer, Sarah Brough, Michael J. I. Brown, Yjan Gordon, Benne W. Holwerda, Denis Leahy, Ángel R. López-Sánchez, Joshua R. Marvil, Tamal Mukherjee, Isabella Prandoni, Stanislav S. Shabala, Tessa Vernstrom, Tayyaba Zafar
We propose a new method for identifying active galactic nuclei (AGN) in low mass (M* ≤ 1010M⊙) galaxies. This method relies on spectral energy distribution (SED) fitting to identify galaxies whose radio flux density has an excess over that expected from star formation alone. Combining data in the Galaxy and Mass Assembly (GAMA) G23 region from GAMA, Evolutionary Map of the Universe (EMU) early science
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A commensal Fast Radio Burst search pipeline for the Murchison Widefield Array Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-01-29 M. Sokolowski, I.S. Morrison, D. C. Price, G. Sleap, B. Crosse, A. Williams, L. Williams, C. James, B.W. Meyers, S. McSweeney, N.D.R. Bhat, G. Anderson
We present a demonstration version of a commensal pipeline for Fast Radio Burst (FRB) searches using a real-time incoherent beam from the Murchison Widefield Array (MWA). The main science target of the pipeline are bright nearby FRBs from the local Universe (including Galactic FRBs like from SGR 1935+2154) which are the best candidates to probe FRB progenitors and understand physical mechanisms powering
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Survey and monitoring of ASKAP’s RFI environment and trends I: Flagging statistics Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-01-29 L. Lourenço, A.P. Chippendale, B. Indermuehle, V.A. Moss, Tara Murphy, T.J. Galvin, G. Hellbourg, A.W. Hotan, E. Lenc, M.T. Whiting
We present an initial analysis of Radio Frequency Interference (RFI) flagging statistics from archived Australian SKA Pathfinder (ASKAP) observations for the ‘Survey and Monitoring of ASKAP’s RFI environment and Trends’ (SMART) project. SMART is a two-part observatoryled project combining analysis of archived observations with a dedicated, comprehensive RFI survey. The survey component covers ASKAP’s
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Plane polarisation in Comptonization process: A Monte Carlo study Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-01-29 Nagendra Kumar
High energies emissions observed in X-ray binaries (XRBs), active galactic nuclei (AGNs) are linearly polarised. The prominent mechanism for X-ray is the Comptonization process. We revisit the theory for polarisation in Compton scattering with unpolarised electrons and note that the ($k \times k^{\prime}$)-coordinate (in which, ($k \times k^{\prime}$) acts as a z-axis, here k and k′ are incident and
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M2P2 I: Maser Monitoring Parkes Program data description and Stokes-I OH maser variability Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-01-22 Anita Hafner, James A. Green, Ashie Burdon, Elena Popova, Dmitry Ladeyschikov, Shari Breen, Ross Alexander Burns, James O. Chibueze, M. D. Gray, Busaba Hutawarakorn Kramer, Gordon MacLeod, Andrey Sobolev, Maxim Voronkov
The Maser Monitoring Parkes Project (M2P2) is an ongoing project to observe masers towards high-mass star-forming regions (HMSFRs) using the 64 m CSIRO Parkes radio telescope, Murriyang. In this paper, we outline the project and introduce Stokes-I data from the first two years of observations. For the 63 sightlines observed in this project we identify a total of 1 514 individual maser features: 14
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Multi-periodicity in the high gravity blue large amplitude pulsator ZTF J071329.02-152125.2 Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-01-17 Chris Koen
New time series photometry of the pulsating hot subdwarf star ZTF J071329.02-152125.2 is presented. Rapid (timescale of hours) changes in the amplitude of the known pulsation in the star was observed. This could be ascribed to beating between three closely spaced frequencies, but analysis of all available photometry finds a range of different frequencies, with widely different amplitudes. A new frequency
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EMU/GAMA: Radio detected galaxies are more obscured than optically selected galaxies Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-01-17 U. T. Ahmed, A. M. Hopkins, J. Ware, Y. A. Gordon, M. Bilicki, M. J. I. Brown, M. Cluver, G. Gürkan, Á. R. López-Sánchez, D. A. Leahy, L. Marchetti, S. Phillipps, I. Prandoni, N. Seymour, E. N. Taylor, E. Vardoulaki
We demonstrate the importance of radio selection in probing heavily obscured galaxy populations. We combine Evolutionary Map of the Universe (EMU) Early Science data in the Galaxy and Mass Assembly (GAMA) G23 field with the GAMA data, providing optical photometry and spectral line measurements, together withWide-field Infrared Survey Explorer (WISE) infrared (IR) photometry, providing IR luminosities
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4XMM J182531.5−144036: A new persistent Be/X-ray binary found within the XMM-Newton serendipitous survey Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-01-15 A.B. Mason, A.J. Norton, J.S. Clark, S.A. Farrell, A.J. Gosling
We aim to investigate the nature of time-variable X-ray sources detected in the XMM-Newton serendipitous survey. The X-ray light curves of objects in the XMM-Newton serendipitous survey were searched for variability, and coincident serendipitous sources observed by Chandra were also investigated. Subsequent infrared spectroscopy of the counterparts to the X-ray objects that were identified using UKIDSS
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The depletion of star-forming gas by AGN activity in radio sources Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2024-01-09 S. J. Curran
Cold, neutral interstellar gas, the reservoir for star formation, is traced through the absorption of the 21-cm continuum radiation by neutral hydrogen (H i). Although detected in one hundred cases in the host galaxies of distant radio sources, only recently have column densities approaching the maximum value observed in Lyman-$\alpha$ absorption systems ($N_{{\textrm{H}\,\scriptsize{\textrm{I}}}}\sim
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Radio continuum from the most massive early-type galaxies detected with ASKAP RACS Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-12-15 Michael J.I. Brown, Teagan A. Clarke, Andrew M. Hopkins, Ray P. Norris, T.H. Jarrett
All very massive early-type galaxies contain supermassive blackholes, but are these blackholes all sufficiently active to produce detectable radio continuum sources? We have used the 887.5 MHz Rapid ASKAP Continuum Survey DR1 to measure the radio emission from morphological early-type galaxies brighter than $K_S=9.5$ selected from the 2MASS Redshift Survey, HyperLEDA, and RC3. In line with previous
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RadioGalaxyNET: Dataset and novel computer vision algorithms for the detection of extended radio galaxies and infrared hosts Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-12-11 Nikhel Gupta, Zeeshan Hayder, Ray P. Norris, Minh Huynh, Lars Petersson
Creating radio galaxy catalogues from next-generation deep surveys requires automated identification of associated components of extended sources and their corresponding infrared hosts. In this paper, we introduce RadioGalaxyNET, a multimodal dataset, and a suite of novel computer vision algorithms designed to automate the detection and localization of multi-component extended radio galaxies and their
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The Rapid ASKAP Continuum Survey V: Cataloguing the sky at 1 367.5 MHz and the second data release of RACS-mid Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-12-11 S. W. Duchesne, J. A. Grundy, George H. Heald, Emil Lenc, James K. Leung, David McConnell, Tara Murphy, Joshua Pritchard, Kovi Rose, Alec J. M. Thomson, Yuanming Wang, Ziteng Wang, Matthew T. Whiting
The Australian SKA Pathfinder (ASKAP) has surveyed the sky at multiple frequencies as part of the Rapid ASKAP Continuum Survey (RACS). The first two RACS observing epochs, at 887.5 (RACS-low) and 1 367.5 (RACS-mid) MHz, have been released (McConnell, et al. 2020, PASA, 37, e048; Duchesne, et al. 2023, PASA, 40, e034). A catalogue of radio sources from RACS-low has also been released, covering the sky
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Evolution of the magnetic field and flows of solar active regions with persistent magnetic bipoles before emergence Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-12-06 C.S. Alley, H. Schunker
Magnetic active regions on the Sun are harbingers of space weather. Understanding the physics of how they form and evolve will improve space weather forecasting. Our aim is to characterise the surface magnetic field and flows for a sample of active regions with persistent magnetic bipoles prior to emergence. We identified 42 emerging active regions (EARs), in the Solar Dynamics Observatory Helioseismic
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Lyman-α at Cosmic Noon II: The relationship between kinematics and Lyman-α in z ∼ 2–3 Lyman break galaxies Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-11-30 Garry Foran, Jeff Cooke, Emily Wisnioski, Naveen Reddy, Charles Steidel
We report for the first time a relationship between galaxy kinematics and net Lyman-$\alpha$ equivalent width (net Ly$\alpha$ EW) in star-forming galaxies during the epoch of peak cosmic star formation. Building on the previously reported broadband imaging segregation of Ly$\alpha$-emitting and Ly$\alpha$-absorbing Lyman break galaxies (LBGs) at $z\sim2$ (Paper I in this series) and previously at $z\sim3$
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Estimating stellar parameters and identifying very metal-poor stars for low-resolution spectra (R ∼ 200) Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-11-28 Tianmin Wu, Yude Bu, Jianhang Xie, Junchao Liang, Wei Liu, Zhenping Yi, Xiaoming Kong, Meng Liu
Very metal-poor (VMP, [Fe/H]<-2.0) stars serve as invaluable repositories of insights into the nature and evolution of the first-generation stars formed in the early galaxy. The upcoming China Space Station Telescope (CSST) will provide us with a large amount of spectral data that may contain plenty of VMP stars, and thus it is crucial to determine the stellar atmospheric parameters ($T_{\textrm{eff}}$
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The MAGPI survey: Drivers of kinematic asymmetries in the ionised gas of z ∼ 0.3 star-forming galaxies Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-11-28 R.S. Bagge, C. Foster, A. Battisti, S. Bellstedt, M. Mun, K. Harborne, S. Barsanti, T. Mendel, S. Brough, S.M. Croom, C.D.P. Lagos, T. Mukherjee, Y. Peng, R.-S. Remus, G. Santucci, P. Sharda, S. Thater, J. van de Sande, L.M. Valenzuela, E. Wisnioski, T. Zafar, B. Ziegler
Galaxy gas kinematics are sensitive to the physical processes that contribute to a galaxy’s evolution. It is expected that external processes will cause more significant kinematic disturbances in the outer regions, while internal processes will cause more disturbances for the inner regions. Using a subsample of 47 galaxies ($0.27
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Studying the internal structures of the central region of prestellar core L1517B in Taurus molecular cloud using ammonia (NH3) (1,1) and (2,2) lines Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-11-16 Atanu Koley
Measurement of internal structures in the prestellar core is essential for understanding the initial conditions prior to star formation. In this work, we study the ammonia lines (NH $_{3}$ ) (J, K = 1,1 and 2,2) in the central region of the prestellar core L1517B with the Karl G. Jansky Very Large Array (VLA) radio telescope (spatial resolution $\sim$ 3.7′′). Our analysis indicates that the central
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A near-field treatment of aperture synthesis techniques using the Murchison Widefield Array Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-11-10 S. Prabu, S.J. Tingay, A. Williams
Typical radio interferometer observations are performed assuming the source of radiation to be in the far-field of the instrument, resulting in a two-dimensional Fourier relationship between the observed visibilities in the aperture plane and the sky brightness distribution (over a small field of view). When near-field objects are present in an observation, the standard approach applies far-field delays
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Measuring the global 21-cm signal with the MWA-II: improved characterisation of lunar-reflected radio frequency interference Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-11-08 Himanshu Tiwari, Benjamin McKinley, Cathryn M. Trott, Nithyanandan Thyagarajan
Radio interferometers can potentially detect the sky-averaged signal from the Cosmic Dawn (CD) and the Epoch of Reionisation (EoR) by studying the Moon as a thermal block to the foreground sky. The first step is to mitigate the Earth-based radio frequency interference (RFI) reflections (Earthshine) from the Moon, which significantly contaminate the FM band $\approx 88-110$ MHz, crucial to CD-EoR science
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Inviscid protostellar disc ring formation and high-density ring edges due to the ejection and subsequent infall of material onto a protostellar disc Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-11-06 Kurt Liffman
Discs of gas and dust are ubiquitous around protostars. Hypothetical viscous interactions within the disc are thought to cause the gas and dust to accrete onto the star. Turbulence within the disc is theorised to be the source of this disc viscosity. However, observed protostellar disc turbulence often appears to be small and not always conducive to disc accretion. In addition, theories for disc and
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Dynamical aspects of Galactic habitability in N-body simulations Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-11-06 A. Mitrašinović, B. Vukotić, M. Micic, M. M. Ćirković
Recent studies of Galactic evolution revealed that the dynamics of the stellar component might be one of the key factors when considering galactic habitability. We run an N-body simulation model of the Milky Way, which we evolve for 10 Gyr, to study the secular evolution of stellar orbits and the resulting galactic habitability related properties, i.e., the density of the stellar component and close
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Modelling repetition in zDM: A single population of repeating fast radio bursts can explain CHIME data Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-10-26 C.W. James
Regardless of whether or not all fast radio bursts (FRBs) repeat, those that do form a population with a distribution of rates. This work considers a power-law model of this population, with rate distribution $\Phi_r \sim R^{{\gamma_r}}$ between ${R_{\rm min}}$ and ${R_{\rm max}}$. The zDM code is used to model the probability of detecting this population as either apparently once-off or repeat events
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MWA rapid follow-up of gravitational wave transients: Prospects for detecting prompt radio counterparts Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-10-26 J. Tian, G. E. Anderson, A. J. Cooper, K. Gourdji, M. Sokolowski, A. Rowlinson, A. Williams, G. Sleap, D. Dobie, D. L. Kaplan, Tara Murphy, S. J. Tingay, F. H. Panther, P. D. Lasky, A. Bahramian, J. C. A. Miller-Jones, C. W. James, B. W. Meyers, S. J. McSweeney, P. J. Hancock
We present and evaluate the prospects for detecting coherent radio counterparts to gravitational wave (GW) events using Murchison Widefield Array (MWA) triggered observations. The MWA rapid-response system, combined with its buffering mode ( $\sim$ 4 min negative latency), enables us to catch any radio signals produced from seconds prior to hours after a binary neutron star (BNS) merger. The large
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Radio Galaxy Zoo: Tagging radio subjects using text Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-10-16 Dawei Chen, Vinay Kerai, Matthew J. Alger, O. Ivy Wong, Cheng Soon Ong
RadioTalk is a communication platform that enabled members of the Radio Galaxy Zoo (RGZ) citizen science project to engage in discussion threads and provide further descriptions of the radio subjects they were observing in the form of tags and comments. It contains a wealth of auxiliary information which is useful for the morphology identification of complex and extended radio sources. In this paper
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Lyman-α at cosmic noon I: Lyα spectral type selection of z ∼ 2 – 3 Lyman break galaxies with broadband imaging Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-09-28 Garry Foran, Jeff Cooke, Naveen Reddy, Charles Steidel, Alice Shapley
High-redshift Lyman break galaxies (LBGs) are efficiently selected in deep images using as few as three broadband filters, and have been shown to have multiple intrinsic and small- to large-scale environmental properties related to Lyman-$\alpha$. In this paper we demonstrate a statistical relationship between net Lyman-$\alpha$ equivalent width (net Ly$\alpha$ EW) and the optical broadband photometric
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SimSpin v2.6.0—constructing synthetic spectral IFU cubes for comparison with observational surveys Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-09-11 K. E. Harborne, A. Serene, E. J. A. Davies, C. Derkenne, S. Vaughan, A. I. Burdon, C. del P Lagos, R. McDermid, S. O’Toole, C. Power, A. S. G. Robotham, G. Santucci, R. Tobar
In this work, we present a methodology and a corresponding code-base for constructing mock integral field spectrograph (IFS) observations of simulated galaxies in a consistent and reproducible way. Such methods are necessary to improve the collaboration and comparison of observation and theory results, and accelerate our understanding of how the kinematics of galaxies evolve over time. This code, SimSpin
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Deep learning for morphological identification of extended radio galaxies using weak labels Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-09-07 Nikhel Gupta, Zeeshan Hayder, Ray P. Norris, Minh Huynh, Lars Petersson, X. Rosalind Wang, Heinz Andernach, Bärbel S. Koribalski, Miranda Yew, Evan J. Crawford
The present work discusses the use of a weakly-supervised deep learning algorithm that reduces the cost of labelling pixel-level masks for complex radio galaxies with multiple components. The algorithm is trained on weak class-level labels of radio galaxies to get class activation maps (CAMs). The CAMs are further refined using an inter-pixel relations network (IRNet) to get instance segmentation masks
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The Rapid ASKAP Continuum Survey III: Spectra and Polarisation In Cutouts of Extragalactic Sources (SPICE-RACS) first data release Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-08-30 Alec J. M. Thomson, David McConnell, Emil Lenc, Timothy J. Galvin, Lawrence Rudnick, George Heald, Catherine L. Hale, Stefan W. Duchesne, Craig S. Anderson, Ettore Carretti, Christoph Federrath, B. M. Gaensler, Lisa Harvey-Smith, Marijke Haverkorn, Aidan W. Hotan, Yik Ki Ma, Tara Murphy, N. M. McClure-Griffiths, Vanessa A. Moss, Shane P. O’Sullivan, Wasim Raja, Amit Seta, Cameron L. Van Eck, Jennifer
The Australian SKA Pathfinder (ASKAP) radio telescope has carried out a survey of the entire Southern Sky at 887.5 MHz. The wide area, high angular resolution, and broad bandwidth provided by the low-band Rapid ASKAP Continuum Survey (RACS-low) allow the production of a next-generation rotation measure (RM) grid across the entire Southern Sky. Here we introduce this project as Spectral and Polarisation
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The Mopra Southern Galactic Plane CO Survey – data release 4– complete survey Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-08-22 K. O. Cubuk, M. G. Burton, C. Braiding, G. F. Wong, G. Rowell, N. I. Maxted, D. Eden, R. Z. E. Alsaberi, R. Blackwell, R. Enokiya, K. Feijen, M. D. Filipović, M. S. R. Freeman, S. Fujita, M. Ghavam, B. Gunay, B. Indermuehle, K. Hayashi, M. Kohno, T. Nagaya, A. Nishimura, K. Okawa, D. Rebolledo, D. Romano, H. Sano, C. Snoswell, N. F. H. Tothill, K. Tsuge, F. Voisin, Y. Yamane, S. Yoshiike
We present observations of the Mopra carbon monoxide (CO) survey of the Southern Galactic Plane, covering Galactic longitudes spanning $l = 250^{\circ}$ ($-110^{\circ}$) to $l = 355^{\circ}$ ($-5^{\circ}$), with a latitudinal coverage of at least $|b|<1^\circ$, totalling an area of $>$210 deg$^{2}$. These data have been taken at 0.6 arcmin spatial resolution and 0.1 km s$^{-1}$ spectral resolution
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Statistical analysis of kicked black holes from TNG300 simulation Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-08-18 M. Smole, M. Micic
Asymmetric emission of gravitational waves during mergers of black holes (BHs) produces a recoil kick, which can set a newly formed BH on a bound orbit around the centre of its host galaxy, or even completely eject it. To study this population of recoiling BHs we extract properties of galaxies with merging BHs from Illustris TNG300 simulation and then employ both analytical and numerical techniques
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Turbulence measurements in the neutral ISM from Hi-21 cm emission–absorption spectra Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-08-17 Atanu Koley
We study the correlation between the non-thermal velocity dispersion ($\sigma_{nth}$) and the length scale (L) in the neutral interstellar medium (ISM) using a large number of Hi gas components taken from various published Hi surveys and previous Hi studies. We notice that above the length-scale (L) of 0.40 pc, there is a power-law relationship between $\sigma_{nth}$ and L. However, below 0.40 pc,
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Detection of radio emission from stars via proper-motion searches Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-08-11 Laura N. Driessen, George Heald, Stefan W. Duchesne, Tara Murphy, Emil Lenc, James K. Leung, Vanessa A. Moss
We present a method for identifying radio stellar sources using their proper-motion. We demonstrate this method using the FIRST, VLASS, RACS-low and RACS-mid radio surveys, and astrometric information from Gaia Data Release 3. We find eight stellar radio sources using this method, two of which have not previously been identified in the literature as radio stars. We determine that this method probes
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Evolved galaxies in high-density environments across 2.0 ≤ z < 4.2 using the ZFOURGE survey Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-08-09 Georgia R. Hartzenberg, Michael J. Cowley, Andrew M. Hopkins, Rebecca J. Allen
To explore the role environment plays in influencing galaxy evolution at high redshifts, we study $2.0\leq z<4.2$ environments using the FourStar Galaxy Evolution (ZFOURGE) survey. Using galaxies from the COSMOS legacy field with ${\rm log(M_{*}/M_{\odot})}\geq9.5$, we use a seventh nearest neighbour density estimator to quantify galaxy environment, dividing this into bins of low-, intermediate-, and
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A novel approach for variable star classification based on imbalanced learning Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-08-09 Jingyi Zhang, Yanxia Zhang, Zihan Kang, Changhua Li, Yihan Tao, Yongheng Zhao, Xue-Bing Wu
The advent of time-domain sky surveys has generated a vast amount of light variation data, enabling astronomers to investigate variable stars with large-scale samples. However, this also poses new opportunities and challenges for the time-domain research. In this paper, we focus on the classification of variable stars from the Catalina Surveys Data Release 2 and propose an imbalanced learning classifier
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The Rapid ASKAP Continuum Survey IV: continuum imaging at 1367.5 MHz and the first data release of RACS-mid Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-08-02 S. W. Duchesne, A. J. M. Thomson, J. Pritchard, E. Lenc, V. A. Moss, D. McConnell, M. H. Wieringa, M. T. Whiting, Z. Wang, Y. Wang, K. Rose, W. Raja, Tara Murphy, J. K. Leung, M. T. Huynh, A. W. Hotan, T. Hodgson, G. H. Heald
The Australian SKA Pathfinder (ASKAP) is being used to undertake a campaign to rapidly survey the sky in three frequency bands across its operational spectral range. The first pass of the Rapid ASKAP Continuum Survey (RACS) at 887.5 MHz in the low band has already been completed, with images, visibility datasets, and catalogues made available to the wider astronomical community through the CSIRO ASKAP
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Probing the consistency of cosmological contours for supernova cosmology Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-07-24 P. Armstrong, H. Qu, D. Brout, T. M. Davis, R. Kessler, A. G. Kim, C. Lidman, M. Sako, B. E. Tucker
As the scale of cosmological surveys increases, so does the complexity in the analyses. This complexity can often make it difficult to derive the underlying principles, necessitating statistically rigorous testing to ensure the results of an analysis are consistent and reasonable. This is particularly important in multi-probe cosmological analyses like those used in the Dark Energy Survey (DES) and
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Measuring photometric redshifts for high-redshift radio source surveys Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-07-19 K. J. Luken, R. P. Norris, X. R. Wang, L. A. F. Park, Y. Guo, M. D. Filipović
With the advent of deep, all-sky radio surveys, the need for ancillary data to make the most of the new, high-quality radio data from surveys like the Evolutionary Map of the Universe (EMU), GaLactic and Extragalactic All-sky Murchison Widefield Array survey eXtended, Very Large Array Sky Survey, and LOFAR Two-metre Sky Survey is growing rapidly. Radio surveys produce significant numbers of Active
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The Parkes Pulsar Timing Array third data release Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-07-19 Andrew Zic, Daniel J. Reardon, Agastya Kapur, George Hobbs, Rami Mandow, Małgorzata Curyło, Ryan M. Shannon, Jacob Askew, Matthew Bailes, N. D. Ramesh Bhat, Andrew Cameron, Zu-Cheng Chen, Shi Dai, Valentina Di Marco, Yi Feng, Matthew Kerr, Atharva Kulkarni, Marcus E. Lower, Rui Luo, Richard N. Manchester, Matthew T. Miles, Rowina S. Nathan, Stefan Osłowski, Axl F. Rogers, Christopher J. Russell, John
We present the third data release from the Parkes Pulsar Timing Array (PPTA) project. The release contains observations of 32 pulsars obtained using the 64-m Parkes ‘Murriyang’ radio telescope. The data span is up to 18 yr with a typical cadence of 3 weeks. This data release is formed by combining an updated version of our second data release with $\sim$3 yr of more recent data primarily obtained using
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The host galaxy of FRB 20171020A revisited Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-07-11 Karen Lee-Waddell, Clancy W. James, Stuart D. Ryder, Elizabeth K. Mahony, Arash Bahramian, Bärbel S. Koribalski, Pravir Kumar, Lachlan Marnoch, Freya O. North-Hickey, Elaine M. Sadler, Ryan Shannon, Nicolas Tejos, Jessica E. Thorne, Jing Wang, Randall Wayth
The putative host galaxy of FRB 20171020A was first identified as ESO 601-G036 in 2018, but as no repeat bursts have been detected, direct confirmation of the host remains elusive. In light of recent developments in the field, we re-examine this host and determine a new association confidence level of 98%. At 37 Mpc, this makes ESO 601-G036 the third closest FRB host galaxy to be identified to date
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Survey-scale discovery-based research processes: Evaluating a bespoke visualisation environment for astronomical survey data Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-07-05 C. J. Fluke, D. Vohl, V. A. Kilborn, C. Murugeshan
Next-generation astronomical surveys naturally pose challenges for human-centred visualisation and analysis workflows that currently rely on the use of standard desktop display environments. While a significant fraction of the data preparation and analysis will be taken care of by automated pipelines, crucial steps of knowledge discovery can still only be achieved through various level of human interpretation
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Automatic detection of cataclysmic variables from SDSS images Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-06-29 Junfeng Huang, Meixia Qu, Bin Jiang, Yanxia Zhang
Investigating rare and new objects have always been an important direction in astronomy. Cataclysmic variables (CVs) are ideal and natural celestial bodies for studying the accretion process of semi-detached binaries with accretion processes. However, the sample size of CVs must increase because a lager gap exists between the observational and the theoretical expanding CVs. Astronomy has entered the
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On more than two decades of Celestial Reference Frame VLBI observations in the deep south: IVS-CRDS (1995–2021) Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-06-20 S. Weston, A. de Witt, Hana Krásná, Karine Le Bail, Sara Hardin, David Gordon, Shu Fengchun, Alan Fey, Matthias Schartner, Sayan Basu, Oleg Titov, Dirk Behrend, Christopher S. Jacobs, Warren Hankey, Federico Salguero, John E. Reynolds
The International VLBI Service for Geodesy and Astrometry (IVS) regularly provides high-quality data to produce Earth Orientation Parameters (EOP), and for the maintenance and realisation of the International Terrestrial and Celestial Reference Frames, ITRF and ICRF. The first iteration of the celestial reference frame (CRF) at radio wavelengths, the ICRF1, was adopted by the International Astronomical
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DeepGlow: An efficient neural network emulator of physical afterglow models for gamma-ray bursts and gravitational-wave events Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-06-20 Oliver M. Boersma, Joeri van Leeuwen
Gamma-ray bursts (GRBs) and double neutron star merger gravitational-wave events are followed by afterglows that shine from X-rays to radio, and these broadband transients are generally interpreted using analytical models. Such models are relatively fast to execute, and thus easily allow estimates of the energy and geometry parameters of the blast wave, through many trial-and-error model calculations
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Hydra II: Characterisation of Aegean, Caesar, ProFound, PyBDSF, and Selavy source finders Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-06-13 M. M. Boyce, A. M. Hopkins, S. Riggi, L. Rudnick, M. Ramsay, C. L. Hale, J. Marvil, M. T. Whiting, P. Venkataraman, C. P. O’Dea, S. A. Baum, Y. A. Gordon, A. N. Vantyghem, M. Dionyssiou, H. Andernach, J. D. Collier, J. English, B. S. Koribalski, D. Leahy, M. J. Michałowski, S. Safi-Harb, M. Vaccari, E. L. Alexander, M. Cowley, A. D. Kapinska, A. S. G. Robotham, H. Tang
We present a comparison between the performance of a selection of source finders (SFs) using a new software tool called Hydra. The companion paper, Paper I, introduced the Hydra tool and demonstrated its performance using simulated data. Here we apply Hydra to assess the performance of different source finders by analysing real observational data taken from the Evolutionary Map of the Universe (EMU)
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WALLABY pilot survey: The diversity of HI structural parameters in nearby galaxies Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-06-08 T. N. Reynolds, B. Catinella, L. Cortese, N. Deg, H. Dénes, A. Elagali, B.-Q. For, P. Kamphuis, D. Kleiner, B. S. Koribalski, K. Lee-Waddell, C. Murugeshan, W. Raja, J. Rhee, K. Spekkens, L. Staveley-Smith, J. M. van der Hulst, J. Wang, T. Westmeier, O. I. Wong, F. Bigiel, A. Bosma, B. W. Holwerda, D. A. Leahy, M. J. Meyer
We investigate the diversity in the sizes and average surface densities of the neutral atomic hydrogen (H i) gas discs in $\sim$280 nearby galaxies detected by the Widefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY). We combine the uniformly observed, interferometric H i data from pilot observations of the Hydra cluster and NGC 4636 group fields with photometry measured from ultraviolet, optical
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Hydra I: An extensible multi-source-finder comparison and cataloguing tool Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-06-08 M. M. Boyce, A. M. Hopkins, S. Riggi, L. Rudnick, M. Ramsay, C. L. Hale, J. Marvil, M. T. Whiting, P. Venkataraman, C. P. O’Dea, S. A. Baum, Y. A. Gordon, A. N. Vantyghem, M. Dionyssiou, H. Andernach, J. D. Collier, J. English, B. S. Koribalski, D. Leahy, M. J. Michałowski, S. Safi-Harb, M. Vaccari, E. L. Alexander, M. Cowley, A. D. Kapinska, A. S. G. Robotham, H. Tang
The latest generation of radio surveys are now producing sky survey images containing many millions of radio sources. In this context it is highly desirable to understand the performance of radio image source finder (SF) software and to identify an approach that optimises source detection capabilities. We have created Hydra to be an extensible multi-SF and cataloguing tool that can be used to compare
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HYPEREION—A precision system for the detection of the absorption profile centred at 78 MHz in the radio background spectrum Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-05-24 N. Patra, R. Wayth, M. Sokolowski, D. Price, B. McKinley, D. Kenney
The report of a detection of an absorption profile centred at 78 MHz in the continuum radio background spectrum by the EDGES experiment and its interpretation as the redshifted 21 cm signal of cosmological origin has become one of the most debated results of observational cosmology in recent times. The cosmological 21 cm has long been proposed to be a powerful probe for observing the early Universe
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Classical novae in the ASKAP pilot surveys Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-05-24 Ashna Gulati, Tara Murphy, David L. Kaplan, Roberto Soria, James K. Leung, Yuanming Wang, Joshua Pritchard, Emil Lenc, Stefan W. Duchesne, Andrew O’Brien
We present a systematic search for radio counterparts of novae using the Australian Square Kilometer Array Pathfinder (ASKAP). Our search used the Rapid ASKAP Continuum Survey, which covered the entire sky south of declination $+41^{\circ}$ ( $\sim$ $34000$ square degrees) at a central frequency of 887.5 MHz, the Variables and Slow Transients Pilot Survey, which covered $\sim$ $5000$ square degrees
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MWAX: A new correlator for the Murchison Widefield Array Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-04-27 I. S. Morrison, B. Crosse, G. Sleap, R. B. Wayth, A. Williams, M. Johnston-Hollitt, J. Jones, S. J. Tingay, M. Walker, L. Williams
We describe the design, validation, and commissioning of a new correlator termed ‘MWAX’ for the Murchison Widefield Array (MWA) low-frequency radio telescope. MWAX replaces an earlier generation MWA correlator, extending correlation capabilities and providing greater flexibility, scalability, and maintainability. MWAX is designed to exploit current and future Phase II/III upgrades to MWA infrastructure
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VERTICO V: The environmentally driven evolution of the inner cold gas discs of Virgo cluster galaxies Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-04-27 Adam B. Watts, Luca Cortese, Barbara Catinella, Toby Brown, Christine D. Wilson, Nikki Zabel, Ian D. Roberts, Timothy A. Davis, Mallory Thorp, Aeree Chung, Adam R.H. Stevens, Sara L. Ellison, Kristine Spekkens, Laura C. Parker, Yannick M. Bahé, Vicente Villanueva, María Jiménez-Donaire, Dhruv Bisaria, Alessandro Boselli, Alberto D. Bolatto, Bumhyun Lee
The quenching of cluster satellite galaxies is inextricably linked to the suppression of their cold interstellar medium (ISM) by environmental mechanisms. While the removal of neutral atomic hydrogen (H i) at large radii is well studied, how the environment impacts the remaining gas in the centres of galaxies, which are dominated by molecular gas, is less clear. Using new observations from the Virgo
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The role of impact parameter in typical close galaxy flybys Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-04-24 A. Mitrašinović, M. Micic
Close galaxy flybys, interactions during which two galaxies inter-penetrate, are frequent and can significantly affect the evolution of individual galaxies. Equal-mass flybys are extremely rare and almost exclusively distant, while frequent flybys have mass ratios $q=0.1$ or lower, with a secondary galaxy penetrating deep into the primary. This can result in comparable strengths of interaction between
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M dwarfs found in the first Byurakan spectral sky survey database. Gaia EDR3 and TESS data. Some preliminary results Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-04-20 K. S. Gigoyan, A. Sarkissian, G. R. Kostandyan, K. K. Gigoyan, M. Meftah, S. Bekki, N. Azatyan, F. Zamkotsian
In order to gain more information on the 236 M dwarfs identified in the First Byurakan Survey (FBS) low-resolution (lr) spectroscopic database, Gaia EDR3 high-accuracy astrometric and photometric data and Transiting Exoplanet Survey Satellite (TESS) data are used to characterise these M dwarfs and their possible multiplicity. Among the sample of 236 relatively bright $(7.3 < K_S < 14.4)$ M dwarfs,
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The thermal history of the intergalactic medium at 3.9 ≤ z ≤ 4.3 Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-04-18 T. Ondro, R. Gális
A new determination of the temperature of the intergalactic medium (IGM) over $3.9 \leq z \leq 4.3$ is presented. We applied the curvature method on a sample of 10 high-resolution quasar spectra from the Ultraviolet and Visual Echelle Spectrograph on the VLT/ESO. We measured the temperature at mean density by determining the temperature at the characteristic overdensity, which is tight function of
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A monitoring campaign (2013–2020) of ESA’s Mars Express to study interplanetary plasma scintillation Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-04-12 P. Kummamuru, G. Molera Calvés, G. Cimò, S. V. Pogrebenko, T. M. Bocanegra-Bahamón, D. A. Duev, M. D. Md Said, J. Edwards, M. Ma, J. Quick, A. Neidhardt, P. de Vicente, R. Haas, J. Kallunki, G. Maccaferri, G. Colucci, W. J. Yang, L. F. Hao, S. Weston, M. A. Kharinov, A. G. Mikhailov, T. Jung
The radio signal transmitted by the Mars Express (MEX) spacecraft was observed regularly between the years 2013–2020 at X-band (8.42 GHz) using the European Very Long Baseline Interferometry (EVN) network and University of Tasmania’s telescopes. We present a method to describe the solar wind parameters by quantifying the effects of plasma on our radio signal. In doing so, we identify all the uncompensated
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CosmoDRAGoN simulations—I. Dynamics and observable signatures of radio jets in cosmological environments Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-04-12 Patrick M. Yates-Jones, Stanislav S. Shabala, Chris Power, Martin G. H. Krause, Martin J. Hardcastle, Elena A. N. Mohd Noh Velastín, Georgia S. C. Stewart
We present the Cosmological Double Radio Active Galactic Nuclei (CosmoDRAGoN) project: a large suite of simulated AGN jets in cosmological environments. These environments sample the intra-cluster media of galaxy clusters that form in cosmological smooth particle hydrodynamics (SPH) simulations, which we then use as inputs for grid-based hydrodynamic simulations of radio jets. Initially conical jets
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The Southern-sky MWA Rapid Two-metre (SMART) pulsar survey—II. Survey status, pulsar census, and first pulsar discoveries Publ. Astron. Soc. Aust. (IF 6.3) Pub Date : 2023-04-11 N. D. R. Bhat, N. A. Swainston, S. J. McSweeney, M. Xue, B.W. Meyers, S. Kudale, S. Dai, S. E. Tremblay, W. van Straten, R. M. Shannon, K. R. Smith, M. Sokolowski, S. M. Ord, G. Sleap, A. Williams, P. J. Hancock, R. Lange, J. Tocknell, M. Johnston-Hollitt, D. L. Kaplan, S. J. Tingay, M. Walker
In Paper I, we presented an overview of the Southern-sky MWA Rapid Two-metre (SMART) survey, including the survey design and search pipeline. While the combination of MWA’s large field-of-view and the voltage capture system brings a survey speed of ${\sim} 450\, {\textrm{deg}}^{2}\,\textrm{h}^{-1}$ , the progression of the survey relies on the availability of compact configuration of the Phase II array