arXiv subjects

T. J. Galvin

Publications and source records attributed to T. J. Galvin.

At least 19 recordsLinked to original sources

arXiv2026

The MWA Interestingly Deep AStrophysical (MIDAS) Survey: Survey Description and First Data Release

We present the deepest MWA survey to date, targeting the GAMA9 and GAMA23 survey fields at 215.68 MHz. With a bandwidth of 30.72 MHz, the two images cover ${\sim}1250\text{ deg}^2$ for the GAMA9 field and ${\sim}850\text{ deg}^2$ for the GAMA23 field, with an angular resolution of ${\sim}60''$. The GAMA9 image was formed from 1 282 2-min snapshot observations (42.7 hours) and the GAMA23 image from 1 701 observations (56.7 hours) achieving depths of $0.923 \pm 0.003$ and $0.331 \pm 0.001$ mJy/beam at the field centres respectively. We processed the data with an updated version of the GLEAM-X pipeline tuned for deep surveys and make this MWA Deep Imaging Pipeline code public. Updates to the pipeline include automation of the observation downloading, calibration, and imaging along with optimisation of the CLEANing methods and parameters. Above $5σ$, we catalogue 53 419 and 80 407 radio components in the GAMA9 and GAMA23 fields respectively. We find that the completeness corrected source counts for both fields are in good agreement down to $25$-$50$ mJy with those from LOFAR and earlier MWA surveys. We demonstrate the utility of this survey by highlighting a few sources of particular interest and describing future science possible with this survey.

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arXiv2026

The Rapid ASKAP Continuum Survey (RACS) VIII: total intensity and circular polarization images and catalogues at 887.5 MHz from RACS-low2

We present a new data release from the Rapid ASKAP Continuum Survey (RACS), a widefield snapshot radio survey conducted with the Australian SKA Pathfinder (ASKAP). This data release contains the second RACS epoch to make use of ASKAP's low-frequency band, centred on 887.5 MHz with a bandwidth of 288 MHz, referred to as RACS-low2. This RACS-low2 data release includes both Stokes I and V imaging and catalogue data products covering the whole sky up to a declination of ~+48 degrees. RACS-low2 largely follows the observation footprint of the first low-band epoch, though includes additional coverage in the Northern Hemisphere. The observation scheduling and data processing follow previous RACS epochs, making use of autonomous scheduling and holography-derived primary beam models. The Stokes I and V catalogues are derived from images with a median point-spread function (PSF) of 14.2" times 11.8", and have median root-mean-square noise properties of 195 and 163 micro-Jy/PSF, for the Stokes I and V images, respectively. The consolidated Stokes I catalogue contains 3922151 sources. We also constructed a catalogue of Stokes V sources by measuring Stokes V images at the Stokes I source positions. For the 221 Stokes V measurements above the estimated leakage and detection thresholds we provide likely identifications, including detections of 61 radio stars, 85 pulsars, 43 AGN (many likely to be residual leakage), and one source that is not associated with a known astronomical object. These data products, including calibrated visibilities, images, source lists, and consolidated catalogues, are made publicly available through the CSIRO ASKAP Science Data Archive (CASDA).

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arXiv2026

Magnetised CGM Gas at z~1 revealed by SPICE-RACS

Magnetic fields are expected to permeate the circumgalactic medium (CGM) of galaxies, yet direct constraints at high redshift remain limited by the lack of high-quality Faraday rotation measure (RM) data. Using the RMs from SPICE-RACS DR2 combined with the DESI DR1 quasar catalogue, we compile the largest sample to date of 2483 quasar sightlines with associated RMs, including 612 with intervening Mg II absorbers tracing foreground galaxies and 1871 control sightlines without Mg II absorbers. After subtracting the Galactic RM contribution and restricting the analysis to sightlines with low Milky Way HI column density and H$α$ intensity, we obtain a foreground-cleaned sample of 757 quasars (191 Mg II / 566 control) spanning redshifts $0.13<z<3.45$. In this foreground-cleaned sample, Mg II sightlines exhibit a $4.5σ$ excess in the residual RM dispersion of $4.13 \pm 0.91~\mathrm{rad\,m^{-2}}$ relative to the control sample, at a median absorber redshift of $z\sim1.14$. This implies model-dependent CGM magnetic field strengths of $\sim0.4 - 0.8\, μ$G over projected radii of $20 - 150$ kpc. This indicates that substantial CGM magnetisation was already established by $z\sim1$, enabling new constraints on the growth and amplification of magnetic fields in galaxy halos over cosmic time.

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arXiv2026

A newly born spider system at the core of a radio shell: Evidence for a low-energy supernova

In a search for low surface brightness radio nebulae using the ASKAP-EMU survey, we discovered a faint radio shell, G289.6+5.8, and its central point radio source at the position of the soft gamma-ray source IGR J11187-5438. The central radio source is spatially coincident with a previously known low-mass X-ray binary (LMXB) with an M-type donor star. However, the newly determined Gaia DR3 distance of 267 pc and correspondingly low X-ray luminosity (3 x 10e31 erg/s) cast doubt on the LMXB classification. Neither radio nor X-ray pulsations are detected. Chance-alignments between radio shell, central radio source, optical star, gamma-ray, and X-ray sources appear unlikely. By combining all currently available evidence, we conclude that G289.6+5.8 is a remnant of a low-energy core-collapse explosion of an intermediate mass star (~8Msun) in a binary system with an M-type secondary, which remained bound after the explosion. In this scenario, G289.6+5.8 is a supernova remnant, while the central gamma- and X-ray source is associated with a young neutron star driving a pulsar wind interacting with its M-type stellar companion, making IGR J11187-5438 a nascent spider-type X-ray binary.

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arXiv2026

EMU/GAMA: Refining Dust Extinction Corrections for Hα Luminosity Functions Using Radio-Based Calibration

We present a novel approach to correcting H$α$ luminosity functions for dust extinction by calibrating against radio-based star formation rates (SFRs), using data from the Evolutionary Map of the Universe (EMU) and Galaxy and Mass Assembly (GAMA) surveys. Accurate dust correction is essential for deriving SFRs from rest-frame UV-optical emission lines, particularly as the \textit{James Webb Space Telescope} extends such measurements to galaxies at $z>5$. While a luminosity dependence of dust obscuration has long been recognised, our method exploits the empirical relationship between obscured (H$α$) and unobscured (radio) SFRs to provide a dust correction that can be applied where traditional spectroscopic techniques, e.g. Balmer line based approaches, are unavailable. We apply the SFR based dust correction to 25 published H$α$ luminosity functions spanning $0<z<8$, and derive corresponding star formation rate densities (SFRDs). Adopting the locally calibrated H$α$--radio relation ends up with an overestimate of the cosmic SFRD by more than two orders of magnitude at $z\gtrsim1$. Motivated by the luminosity dependent relation in the local Universe, we introduce a new model where the luminosity dependence of the dust obscuration decreases with increasing redshift. This approach can reproduce observed SFRDs across cosmic time. These results highlight the potential of a radio-based calibration for dust correction, where a luminosity dependent correction would need to decline in strength with increasing redshift. This implies that the dust content or distribution in galaxies at early epochs differs substantially from that in the local Universe.

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arXiv2026

GaLactic and Extragalactic All-sky Murchison Widefield Array survey eXtended (GLEAM-X) III: Galactic Plane

We present the third data release for the Galactic and Extragalactic All-Sky Murchison Widefield Array eXtended (GLEAM-X) survey, covering = 3800 deg2 of the southern Galactic Plane (GP) with \ang{233} < l < \ang{44} and |b| < \ang{11} across a frequency range of 72 - 231 MHz divided into 20 sub-bands. GLEAM-X observations were taken using the "extended" Phase-II configuration of the Murchison Widefield Array (MWA), which features baselines ranging from approximately 12 m to 5 km. This configuration limits sensitivity to the diffuse structure of the GP, with an angular resolution range of about 45'' to 2'. To achieve lower noise levels while being sensitive to a wide range of spatial scales (45''- \ang{15}), we combined these observations with the previous Galactic and Extragalactic All-Sky Murchison Widefield Array (GLEAM) survey. For the area covered, we provide images spanning the whole frequency range. A wide-band image over 170 - 231 MHz, with RMS noise of = 3 - 6 mJy/beam and source position accuracy within 1 arcseconds, is then used to perform source-finding, which yields 98,207 elements measured across 20 x 7.68 MHz frequency bands. The catalogue is 90% complete at 50 mJy within \ang{233} < l < \ang{324} and at 125 mJy in \ang{290} < l < \ang{44}, while it is 99.3% reliable overall. All the images and the catalogue are available online for download.

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arXiv2025

Limits on Unintended Radio Emission from Geostationary and Geosynchronous Satellites in the SKA-Low Frequency Range

We search data from the GLEAM-X survey, obtained with the Murchison Widefield Array (MWA) in 2020, for the presence of radio frequency interference from distant Earth-orbiting satellites, in the form of unintended emissions similar to those recently seen from objects in Low Earth Orbits (LEO). Using the GLEAM-X Dec = 1.6 degree pointing, which is stationary in azimuth (on the local Meridian) and elevation (near the celestial Equator), the very wide field of view of the MWA maintains custody of a large number of satellites in geostationary and geosynchronous (GEO) orbits in this direction for long periods of time. We use one night of GLEAM-X data in the 72 - 231 MHz frequency range to form stacked images at the predicted coordinates of up to 162 such satellites, in order to search for unintended radio emission. In the majority of cases, we reach 4 sigma upper limits of better than 1 mW Equivalent Isotropic Radiated Power (EIRP) in a 30.72 MHz bandwidth (dual polarisation), with the best limits below 10 uW. No convincing evidence for unintended emissions at these detection thresholds was found. This study builds on recent work showing an increasing prevalence of unintended emissions from satellites in LEO. Any such emission from objects in GEO could be a significant contributor to radio frequency interference experienced by the low frequency Square Kilometre Array and warrants monitoring. The current study forms a baseline for comparisons to future monitoring.

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arXiv2025

GLEAM-300: The GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey at 300 MHz

In this paper we present a wide-field radio survey at 300 MHz covering the sky from $-90^\circ \leq δ_\text{J2000} \lesssim +40^\circ$ using the Murchison Widefield Array (MWA). This 300-MHz survey follows the Galactic and Extragalactic All-sky MWA (GLEAM) survey, and provides an additional comparatively high-frequency data point to existing multi-frequency (72-231 MHz) data. With this data release we provide mosaic images and a catalogue of compact source components. We use two-minute snapshot observations covering 2015-2016, combining overlapping two-minute snapshot images to provide full-sensitivity mosaic images with a median root-mean-square noise of $9.1_{-2.8}^{+5.5}$ mJy beam$^{-1}$ and median angular resolution of $128.8^{\prime\prime} \times 112.5^{\prime\prime}$, with some position-dependent variation. We find a total of 338 080 unique Gaussian components across the mosaic images. The survey is the first at 300 MHz from the MWA covering the whole Southern Hemisphere. It provides a unique spectral data point that complements the existing GLEAM survey and the ongoing GLEAM-eXtended survey, and points toward results from the upcoming SKA-Low surveys.

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arXiv2025

Low radio frequency detections of known pulsars and identification of new candidates with GLEAM-X: GP

Image-based searches have become a complementary approach for identifying pulsars, particularly at MHz frequencies where scattering and high dispersion measures affect high-time resolution observations. In this work, we searched the Galactic Plane (GP) data release from the GaLactic and Extragalactic All-Sky Murchison Widefield Array eXtended (GLEAM-X) survey, a widefield continuum radio survey covering the 72 - 231 MHz frequency range, at the positions of known pulsars in the ATNF catalogue (version 2.6.2) that lie within its sky coverage. We present the spectral energy distribution for 193 known pulsars located at |b| < 11deg. Notably, 106 of these represent the first detections below 400 MHz. We also cross-match the GLEAM-X: GP compact source catalogue with unassociated sources in the Fermi Large Area Telescope (LAT) catalogue, filtering for gamma-ray spectral and variability properties, as well as coincidence with Active Galactic Nuclei (AGN). We have identified 106 possible pulsar candidates. This work demonstrates the importance of sensitive, low-frequency Galactic plane surveys for detecting emission from known pulsars and presents a potential way of searching for new pulsar candidates that would otherwise be missed by traditional time-domain searches.

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arXiv2025

ASKAP-EMU radio continuum detection of planetary nebula NGC 5189: the "Infinity" nebula

We report the radio continuum detection of well known Galactic Planetary Nebula (PN) NGC 5189, observed at 943 MHz during the Australian Square Kilometre Array Pathfinder (ASKAP) Evolutionary Map of the Universe (EMU) survey. Two detections of NGC 5189 have been made during the survey, of better resolution than previous radio surveys. Both measurements of the integrated flux density are consistent with each other, at $S_{\rm 943\,MHz} = 0.33\pm0.03$ Jy, and the spectral luminosity is $L_{\rm{943\,MHz}}$ = 8.89 $\times$ 10$^{13}$ W m$^{-2}$ Hz$^{-1}$. Using available flux density measurements for radio-detections of NGC 5189, we calculate a radio surface brightness at 1 GHz and measure $Σ_{\rm 1~GHz}$ = 6.0 $\times$ 10$^{-21}$ W m$^{-2}$ Hz$^{-1}$ sr$^{-1}$, which is in the expected range for Galactic PNe. We measure an apparent size of 3.4${'}$ $\times$ 2.2${'}$ corresponding to physical diameters of 1.48 pc $\times$ 0.96 pc, and combine available radio observations of NGC 5189 to estimate a spectral index of $α$ = 0.12 $\pm$ 0.05. Hence, we agree with previous findings that NGC 5189 is a thermal (free-free) emitting nebula. Additional measurements of the optical depth ($τ= 0.00246$) and electron density ($N_{e} = 138~cm^{-3}$) support our findings that NGC 5189 is optically thin at 943 MHz. Furthermore, the radio contours from the ASKAP-EMU image have been overlaid onto a Hubble Space Telescope (HST) Wide Field Camera 3 image, demonstrating that the radio morphology closely traces the optical. Notably, the contour alignment for the innermost region highlights the two envelopes of gas previously reported to be low-ionisation structures, which is considered a defining feature of post common-envelope PNe that surround a central Wolf-Rayet star.

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arXiv2025

The Polarisation Sky Survey of the Universe's Magnetism (POSSUM): Science Goals and Survey Description

The Australian SKA Pathfinder (ASKAP) offers powerful new capabilities for studying the polarised and magnetised Universe at radio wavelengths. In this paper, we introduce the Polarisation Sky Survey of the Universe's Magnetism (POSSUM), a groundbreaking survey with three primary objectives: (1) to create a comprehensive Faraday rotation measure (RM) grid of up to one million compact extragalactic sources across the southern ~50 per cent of the sky (20,630 deg$^2$); (2) to map the intrinsic polarisation and RM properties of a wide range of discrete extragalactic and Galactic objects over the same area; and (3) to contribute interferometric data with excellent surface brightness sensitivity, which can be combined with single-dish data to study the diffuse Galactic interstellar medium. Observations for the full POSSUM survey commenced in May 2023 and are expected to conclude by mid-2028. POSSUM will achieve an RM grid density of around 30-50 RMs per square degree with a median measurement uncertainty of ~1 rad m$^{-2}$. The survey operates primarily over a frequency range of 800-1088 MHz, with an angular resolution of 20'' and a typical RMS sensitivity in Stokes $Q$ or $U$ of 18 $μ$Jy beam$^{-1}$. Additionally, the survey will be supplemented by similar observations covering 1296-1440 MHz over 38 per cent of the sky. POSSUM will enable the discovery and detailed investigation of magnetised phenomena in a wide range of cosmic environments, as well as the interplay between these components. This paper reviews the current science case developed by the POSSUM Collaboration and provides an overview of POSSUM's observations, data processing, outputs, and its complementarity with other radio and multi-wavelength surveys, including future work with the SKA. [Abstract abridged]

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arXiv2025

The Evolutionary Map of the Universe: A new radio atlas for the southern hemisphere sky

We present the Evolutionary Map of the Universe (EMU) survey conducted with the Australian Square Kilometre Array Pathfinder (ASKAP). EMU aims to deliver the touchstone radio atlas of the southern hemisphere. We introduce EMU and review its science drivers and key science goals, updated and tailored to the current ASKAP five-year survey plan. The development of the survey strategy and planned sky coverage is presented, along with the operational aspects of the survey and associated data analysis, together with a selection of diagnostics demonstrating the imaging quality and data characteristics. We give a general description of the value-added data pipeline and data products before concluding with a discussion of links to other surveys and projects and an outline of EMU's legacy value.

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arXiv2025

A radio transient with unusually slow periodic emission

The high-frequency radio sky is bursting with synchrotron transients from massive stellar explosions and accretion events, but the low-frequency radio sky has so far been quiet beyond the Galactic pulsar population and the long-term scintillation of AGN. The low-frequency band, however, is sensitive to exotic coherent and polarised radio emission processes such as electron cyclotron maser emission from flaring M-dwarfs [1], stellar magnetospheric plasma interactions with exoplanets [2], and a population of steep-spectrum pulsars [3], making Galactic plane searches a prospect for blind transient discovery. Here we report an analysis of archival low-frequency radio data that reveals a periodic, low-frequency radio transient. We find that the source pulses every 18.18 minutes, an unusual periodicity not previously observed. The emission is highly linearly polarised, bright, persists for 30--60 s on each occurrence, and is visible across a broad frequency range. At times the pulses comprise short ($<0.5$-s) duration bursts; at others, a smoother profile is observed. These profiles evolve on timescales of hours. By measuring the dispersion of the radio pulses with respect to frequency, we have localised the source to within our own Galaxy, and suggest that it could be an ultra-long period magnetar.

astro-ph.HE↗

arXiv2025

A long-period radio transient active for three decades

Recently several long-period radio transients have been discovered, with strongly polarised coherent radio pulses appearing on timescales between tens to thousands of seconds [1,2]. In some cases the radio pulses have been interpreted as coming from rotating neutron stars with extremely strong magnetic fields, known as magnetars; the origin of other, occasionally periodic and less well-sampled radio transients, is still debated [3]. Coherent periodic radio emission is usually explained by rotating dipolar magnetic fields and pair production mechanisms, but such models do not easily predict radio emission from such slowly-rotating neutron stars and maintain it for extended times. On the other hand, highly magnetic isolated white dwarfs would be expected to have long spin periodicities, but periodic coherent radio emission has not yet been directly detected from these sources. Here we report observations of a long-period (21 minutes) radio transient, which we have labeled GPMJ1839-10. The pulses vary in brightness by two orders of magnitude, last between 30 and 300 seconds, and have quasi-periodic substructure. The observations prompted a search of radio archives, and we found that the source has been repeating since at least 1988. The archival data enabled constraint of the period derivative to $<3.6\times10^{-13}$s s$^{-1}$, which is at the very limit of any classical theoretical model that predicts dipolar radio emission from an isolated neutron star.

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arXiv2025

The Rapid ASKAP Continuum Survey (RACS) VI: The RACS-high 1655.5 MHz images and catalogue

We have conducted a widefield, wideband, snapshot survey using the Australian SKA Pathfinder (ASKAP) referred to as the Rapid ASKAP Continuum Survey (RACS). RACS covers $\approx$ 90% of the sky, with multiple observing epochs in three frequency bands sampling the ASKAP frequency range of 700 to 1800 MHz. This paper describes the third major epoch at 1655.5 MHz, RACS-high, and the subsequent imaging and catalogue data release. The RACS-high observations at 1655.5 MHz are otherwise similar to the previously released RACS-mid (at 1367.5 MHz), and were calibrated and imaged with minimal changes. From the 1493 images covering the sky up to declination $\approx$ +48$^\circ$, we present a catalogue of 2 677 509 radio sources. The catalogue is constructed from images with a median root-mean-square noise of $\approx$ 195 $μ$Jy PSF$^{-1}$ (point-spread function) and a median angular resolution of 11.8" by 8.1". The overall reliability of the catalogue is estimated to be 99.18%, and we find a decrease in reliability as angular resolution improves. We estimate the brightness scale to be accurate to 10%, and the astrometric accuracy to be within $\approx$ 0.6" in right ascension and $\approx$ 0.7" in declination after correction of a systematic declination-dependent offset. All data products from RACS-high, including calibrated visibility datasets, images from individual observations, full-sensitivity mosaics, and the all-sky catalogue are available at the CSIRO ASKAP Science Data Archive.

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arXiv2024

Low-Frequency Turnover Star Forming Galaxies I: Radio Continuum Observations and Global Properties

The broad-band radio spectral energy distribution (SED) of star-forming galaxies (SFGs) contains a wealth of complex physics. We aim to determine the physical emission and loss processes causing radio SED curvature and steepening to see which observed global astrophysical properties are correlated with radio SED complexity. We have acquired radio continuum data between 70 MHz and 17 GHz for a sample of 19 southern local (z < 0.04) SFGs. Of this sample 11 are selected to contain low-frequency (< 300 MHz) turnovers (LFTOs) in their SEDs and eight are control galaxies with similar global properties. We model the radio SEDs for our sample using a Bayesian framework whereby radio emission (synchrotron and free-free) and absorption or loss processes are included modularly. We find that without the inclusion of higher frequency data, single synchrotron power-law based models are always preferred for our sample; however, additional processes including free-free absorption (FFA) and synchrotron losses are often required to accurately model radio SED complexity in SFGs. The fitted synchrotron spectral indices range from -0.45 to -1.07 and are strongly anticorrelated with stellar mass suggesting that synchrotron losses are the dominant mechanism acting to steepen the spectral index in larger nearby SFGs. We find that LFTOs in the radio SED are independent from the inclination. The merging systems in our SFG sample have elevated specific star formation rates and flatter fitted spectral indices with unconstrained LFTOs. Lastly, we find no significant separation in global properties between SFGs with or without modelled LFTOs. Overall LFTOs are likely caused by a combination of FFA and ionisation losses in individual recent starburst regions with specific orientations and interstellar medium properties that, when averaged over the entire galaxy, do not correlate with global astrophysical properties.

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arXiv2024

A 2.9-hour periodic radio transient with an optical counterpart

We present a long-period radio transient (GLEAM-X J0704-37) discovered to have an optical counterpart, consistent with a cool main sequence star of spectral type M3. The radio pulsations occur at the longest period yet found, 2.9 hours, and were discovered in archival low-frequency data from the Murchison Widefield Array (MWA). High time resolution observations from MeerKAT show that pulsations from the source display complex microstructure and high linear polarisation, suggesting a pulsar-like emission mechanism occurring due to strong, ordered magnetic fields. The timing residuals, measured over more than a decade, show tentative evidence of a ~6-yr modulation. The high Galactic latitude of the system and the M-dwarf star excludes a magnetar interpretation, suggesting a more likely M-dwarf / white dwarf binary scenario for this system.

astro-ph.SR↗

arXiv2024

The GLEAMing of the first supermassive black holes: III. Radio sources with ultra-faint host galaxies

We present deep near-infrared $K_{\rm s}$-band imaging for 35 of the 53 sources from the high-redshift ($z > 2$) radio galaxy candidate sample defined in Broderick et al. (2022). These images were obtained using the High-Acuity Widefield $K$-band Imager (HAWK-I) on the Very Large Telescope. Host galaxies are detected for 27 of the sources, with $K_{\rm s} \approx 21.6$$-$$23.0$ mag (2$''$ diameter apertures; AB). The remaining eight targets are not detected to a median $3σ$ depth of $K_{\rm s} \approx 23.3$ mag ($2''$ diameter apertures). We examine the radio and near-infrared flux densities of the 35 sources, comparing them to the known $z > 3$ powerful radio galaxies with 500-MHz radio luminosities $L_{500\,{\rm MHz}} > 10^{27}$ W Hz$^{-1}$. By plotting 150-MHz flux density versus $K_{\rm s}$-band flux density, we find that, similar to the sources from the literature, these new targets have large radio to near-infrared flux density ratios, but extending the distribution to fainter flux densities. Five of the eight HAWK-I deep non-detections have a median $3σ$ lower limit of $K_{\rm s} \gtrsim 23.8$ mag ($1.5''$ diameter apertures); these five targets, along with a further source from Broderick et al. (2022) with a deep non-detection ($K_{\rm s} \gtrsim 23.7$ mag; $3σ$; $2''$ diameter aperture) in the Southern H-ATLAS Regions $K_{\rm s}$-band Survey, are considered candidates to be ultra-high-redshift ($z > 5$) radio galaxies. The extreme radio to near-infrared flux density ratios ($>10^5$) for these six sources are comparable to TN J0924$-$2201, GLEAM J0856$+$0223 and TGSS J1530$+$1049, the three known powerful radio galaxies at $z > 5$. For a selection of galaxy templates with different stellar masses, we show that $z \gtrsim 4.2$ is a plausible scenario for our ultra-high-redshift candidates if the stellar mass $M_{\rm *} \gtrsim 10^{10.5}\,{\rm M}_\odot$. [abridged]

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