Cosmology and Nongalactic Astrophysics
TDCOSMO XXVI: Uniform lens modeling of eight doubly imaged quasars
Ryan Brady, Xiang-Yu Huang, Simon Birrer et al. (+7 more)
We present the first uniform gravitational lens modeling analysis of eight doubly imaged
quasars from multi-band observations with the Hubble Space
Telescope. Previous time-delay cosmography analyses by the TDCOSMO Collaboration have primarily relied on quadruply imaged
quasars, while doubly imaged systems, despite being more abundant, remain underutilized due to their fewer
geometric constraints. Using an open-source $\texttt{Lenstronomy}$ framework, we reconstruct the
lensing systems with a pipeline tailored for doubles. Comparing our results to the literature, the modeled Einstein radii agree at an average of 1.5$\sigma$, which is expected given data and modeling heterogeneity, while modeled image separations differ from
Gaia DR2 measurements with an r.m.s of only 3.6 mas. We find a strong correlation between Fermat potential precision and the surface brightness of the spatially extended host arcs, establishing that arc surface brightness is the primary driver of mass model precision in doubly imaged systems. To further quantify the information contributed by the lensed arcs, we performed a conjugate point analysis that uses only the
quasar image positions to constrain the lens mass profiles. The resulting posteriors are substantially broader than those from full image modeling, and a strong anti-correlation between mass parameter hypervolume and arc magnitude additionally confirms that arc brightness determines the degree to which the lens mass profile can be constrained in doubles. A hierarchical cosmographic analysis incorporating time-delay measurements and
stellar kinematics to infer $\text{H}_0$ will be presented in a subsequent publication. The uniform pipeline and arc surface brightness trends established here will significantly accelerate the construction of time-delay cosmography samples from the large lens populations expected from LSST, Roman, and Euclid.
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All authors Ryan Brady, Xiang-Yu Huang, Simon Birrer, Anowar J. Shajib, Nafis Sadik Nihal, Cameron Lemon, Martin Millon, Veronica Motta, Dominique Sluse, Frederic Courbin
Astrophysics of Galaxies
Can BLR line profile shape improve single-epoch black hole mass estimates?
Lizvette Villafaña, Tommaso Treu, Shu Wang et al. (+7 more)
The virial coefficient ($f$), which is meant to encapsulate broad-line region (BLR) geometry and kinematics, remains one of the largest sources of systematic uncertainty in black hole mass estimates for Active
Galactic Nuclei (AGNs). While the use of a sample average $\langle f \rangle$ enables black hole mass estimates across large samples and cosmological distances, individual AGNs may deviate from this average due to differences in BLR structure and viewing angle. In previous work, we reported marginal evidence for a correlation between $f$ and the shape of the broad H$\beta$ emission line, $\log_{10}(\mathrm{FWHM}/\sigma)$. In this work, we update our sample to include ten new sources with CARAMEL BLR dynamical modeling, increasing both the black hole mass range and statistical power of our analysis. We find marginal evidence for a correlation between $f$ and $\log_{10}(\mathrm{FWHM}/\sigma)$, with a slope and intrinsic scatter consistent with previous results. The confirmation of this trend across a larger sample further supports the idea that line profile shape may reflect BLR properties in a way that directly impacts $f$. If confirmed with future BLR dynamical modeling of sources within a wider range of $\log_{10}(\mathrm{FWHM}/\sigma)$, this relationship could enable empirical estimates of the virial coefficient and improve single-epoch black hole mass estimates across
cosmic time.
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All authors Lizvette Villafaña, Tommaso Treu, Shu Wang, Misty C. Bentz, Brendon J. Brewer, Aaron J. Barth, Jong-Hak Woo, Matthew A. Malkan, Vardha N. Bennert, Vivian U
High Energy Astrophysical Phenomena
Ultra-thick warm absorbers: Enlarging the parameter space of AGN ionised outflows
R. Middei, E. Piconcelli, E. Nardini et al. (+9 more)
The analysis of X-ray absorption features in active
galactic nuclei (AGN) provides a wealth of information about the physical properties of the matter surrounding supermassive black holes (SMBHs). While standard correlations between the ionisation state, column density, and velocity typically distinguish between disc winds and warm absorbers, some sources exhibit properties that significantly deviate from these trends. We investigate a class of X-ray absorbers, which we define as ultra-thick warm absorbers (UTWAs), identified in a sample of 12 AGN. These absorbers are characterised by exceptionally high column densities and ionisation parameters (($\log (N_{\rm H}/\rm cm^{-2})\gtrsim22.5$ and $0.5 \lesssim \log(\xi/\rm erg~cm~s^{-1})$ $ \lesssim 2.5$)) that lie outside the typical ranges observed in standard warm absorbers. We performed detailed X-ray spectral analyses of both unpublished and archival XMM-Newton, NuSTAR, and Swift
datasets to characterise the physical properties of UTWAs in four of these twelve sources. We studied their variability on timescales ranging from days to years and explored their connection with other spectral features. All AGN hosting UTWAs in our sample exhibit extreme soft X-ray variability, in some cases up to an order of magnitude, primarily driven by changes in the absorbing gas. In a subset of these sources (four out of 12), the UTWAs are accompanied by signatures of ultra-fast
outflows (UFOs) in the Fe K$\alpha$ energy range. UTWAs represent a rare but crucial phase of AGN feedback. We discuss their physical origin, their potential connection with UFOs, and provide insights into why these high-column density, unusually ionised absorbers appear so rarely in local AGN samples.
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All authors R. Middei, E. Piconcelli, E. Nardini, A. Marinucci, M. Laurenti, A. Luminari, A. Trindade Falcão, A. Tortosa, M. Perri, S. Puccetti, D. Ł. Król, L. Borrelli
Astrophysics of Galaxies
Decoupling the AGN outflow and star-forming disk kinematics in the nuclear region of NGC 7582 with JWST NIRSpec and MIRI/MRS
Oscar Veenema, Niranjan Thatte, Dimitra Rigopoulou et al. (+24 more)
We present a detailed study of the inner regions of NGC~7582, a nearby Seyfert~2
galaxy, from the
Galaxy Activity,
Torus and
Outflow Survey (GATOS). The
galaxy hosts a circumnuclear
star-forming disk and an AGN-driven biconical ionised
outflow. Using JWST NIRSpec and MIRI/MRS integral-field spectroscopy, we analyse ionic emission lines spanning a wide range of ionisation potentials (IPs, $\sim 8$–$126$ eV). Gaussian line-profile fitting reveals kinematic stratification: low-IP species ($\lesssim 20$ eV; e.g., [Fe II], [Ar II], [Ne II]) trace ordered disk rotation with PA $\sim -12 \pm 3^\circ$, while high-IP species ($\gtrsim 35$ eV; e.g., [O IV], [Mg IV], [Ne V]) follow the
outflow with PA $\sim 54 \pm 10^\circ$. Outflowing gas exhibits systematically higher velocity dispersions ($119 \pm 13$ km/s) than the disk ($78 \pm 11$ km/s), consistent with turbulent or bulk motions. Intermediate-IP lines, [S III], [Ar III], and [Ne III], show contributions from both components, with the
outflow characterised by higher dispersion, lower amplitude, and higher velocities in double-Gaussian fits. For these lines, a thin inclined disk plus one-dimensional
outflow model enables robust separation and quantification of the disk and
outflow velocity fields. The
outflow is consistent with a hollow bicone capable of accelerating gas beyond the local escape velocity, implying most material is unlikely to be re-accreted. The ionisation cone opening angle shows no dependence on IP, indicating the AGN
torus polar regions are largely unobscured. Our study provides new insights into AGN-driven
outflows and circumnuclear disk dynamics, offering a framework to disentangle overlapping ISM kinematics in nearby active
galaxies.
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All authors Oscar Veenema, Niranjan Thatte, Dimitra Rigopoulou, Ismael García-Bernete, Almudena Alonso-Herrero, Miguel Pereira-Santaella, Anelise Audibert, Enrica Bellocchi, Andrew J. Bunker, Steph Campbell, Francoise Combes, Ric I. Davies, Fergus R. Donnan, Santiago García-Burillo, Omaira Gonzalez Martin, Laura Hermosa Muñoz, Erin K. S. Hicks, Sebastian F. Hoenig, Alvaro Labiano, Nancy A. Levenson, Chris Packham, Cristina Ramos Almeida, Claudio Ricci, Rogemar A. Riffel, David Rosario, Taro Shimizu, Lulu Zhang
Instrumentation and Methods for Astrophysics
Joint Multiband Photometry with crowdsource
Jayashree Behera, Edward F. Schlafly, Aaron M. Meisner et al. (+1 more)
We present a new multiband extension to the crowdsource photometric pipeline, enabling simultaneous fitting across multiple imaging bands in crowded fields. The core idea is that multiple images of the same part of the sky should have the same sources at the same locations; only the fluxes in the different images should be allowed to vary in fitting. The framework also allows us to use all images of a given region to detect faint sources, with configurable weighting among the different bandpasses as appropriate for different source spectra. Similar concepts are already present in other crowded field packages like DAOPHOT and DOLPHOT; we now include it in the crowdsource fitting approach. We describe the mathematical formulation of the multiband fit and demonstrate its performance using the Wide-field Infrared Survey Explorer (WISE) W1 and W2 imaging as a concrete application. The multiband
algorithm improves flux consistency and reduces band-to-band positional scatter relative to independent-band fitting. We test the method on unWISE coadded tiles spanning both sparse and crowded regions and quantify improvements in photometric agreement and astrometric stability. This framework provides a general foundation for future multiband crowded-field catalogs.
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All authors Jayashree Behera, Edward F. Schlafly, Aaron M. Meisner, Lucas Napolitano
Astrophysics of Galaxies
$N$-body modelling of the ED-2 stream progenitor shows Gaia BH3's formation involved dynamical interactions
Daniel Marín Pina, Mark Gieles, Sara Rastello et al. (+3 more)
Context. The
Gaia collaboration announced the discovery of a binary of a massive black hole (33 M$_\odot$) with a low-mass
giant star (
Gaia BH3) in the ED-2
stellar stream. The properties of this binary, as well as its position in the stream, challenge a formation scenario invoking only isolated binary
evolution. Aims. We aim to quantify the importance of cluster dynamics in the formation of
Gaia BH3 in the progenitor cluster of the ED-2 stream. Methods. We perform detailed N-body simulations of the progenitor cluster of the ED-2 stream, including the effects of single and binary
stellar evolution. We compare these simulations to observations of the ED-2 stream and the properties of
Gaia BH3. Results. We determine that
Gaia BH3 most likely formed as an exchange binary which underwent multiple strong dynamical interactions. We highlight the importance of cluster dynamics in assembling
Gaia BH3, and disfavour a formation scenario where it evolved unperturbed by dynamical interactions. Conclusions. The role of dynamics should be considered when interpreting the properties of the population of
star-black hole binaries found in the next
Gaia Data Release.
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All authors Daniel Marín Pina, Mark Gieles, Sara Rastello, Clàudia Garcia-Diago, Giuliano Iorio, Marc Ardèvol
Instrumentation and Methods for Astrophysics
Seismic background mitigation with the Lunar Gravitational-wave Antenna
Han Yan and Jan Harms
Lunar gravitational-wave (GW) detectors relying on the measurement of the response of the Moon to GWs are susceptible to a seismic background, which might pose a fundamental sensitivity limitation. The Lunar Gravitational-wave
Antenna (LGWA) was conceived as an array of accelerometers with the idea that data can be processed to distinguish between a GW signal and the seismic background. As a result, the seismic noise of the GW measurement would be mitigated. However, so far, no quantitative assessment of the mitigation of the seismic background has been provided. In this article, we derive the analytical expressions for the optimal squared signal-to-noise ratio for a two-station array in an isotropic, random, Gaussian seismic field. Our numerical analysis reveals that the capacity to mitigate the seismic noise critically depends on the distance between the two stations relative to the seismic-correlation length. We demonstrate that optimal placement of the two stations can yield significant improvements in the equivalent seismic noise amplitude spectral density (ASD), approximately a factor of 2.3 at 0.3 Hz, compared to the measurement with a single station in the seismic-noise-dominated limit. The equivalent ASD of the seismic noise also exhibits distinct oscillatory and mitigation features arising from the Bessel-function structure of the noise correlation.
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Cosmology and Nongalactic Astrophysics
Bound or blown: the fate of hot gas in galaxy groups
R. Seppi, D. Eckert, J. Schaye et al. (+14 more)
The impact of AGN feedback on the hot gas content of
galaxy groups remains a key uncertainty in
galaxy formation and its connection to the large scale structure of the Universe. We aim to compare the XMM-Newton Group AGN Project (X-GAP) sample to the hydrodynamical FLAMINGO simulations, which span a wide range of AGN feedback prescriptions. We construct X-GAP analogues by forward-modelling the full selection function, including detection and observational systematics, and generate end-to-end XMM-Newton mock observations analysed consistently with the data. We study multiple observables, including the L–T and Mgas–T relations, number of groups, mean temperature, and velocity dispersion, accounting for their covariance. The forward model accurately recovers input luminosities, gas masses, and core-excised temperatures for regular systems, enabling direct comparison in observable space. The normalisation of the scaling relations is the best discriminator between feedback models, while
cosmic variance introduces > 20% fluctuations in the number of detected systems, making counts alone a weak discriminator. Models with intermediate feedback strength provide the best agreement with X-GAP, with the fgas-2sigma model yielding the lowest tension of only 0.8sigma, while the most extreme feedback scenario (fgas-8sigma) is ruled out at > 4sigma. Our results indicate that the thermodynamic properties of
galaxy groups favour feedback stronger than the fiducial FLAMINGO calibration, but disfavour the most ejective models. This highlights the importance of combining forward modelling and multi-observable constraints to probe the fate of hot
baryons in low-mass
haloes.
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All authors R. Seppi, D. Eckert, J. Schaye, J. Braspenning, M. Schaller, B. D. Oppenheimer, E. O'Sullivan, F. Gastaldello, L. Lovisari, M. A. Bourne, M. Sun, A. Finoguenov, H. Khalil, G. Gozaliasl, K. Kolokythas, Y. E. Bahar, R. Santra
Instrumentation and Methods for Astrophysics
The effects of image augmentations when training machine learning models in astronomy
Leon H. Butterworth and Ashley Spindler
We measure the influence of image augmentations and training
dataset size when training a deep neural network to classify
galaxy morphology. Data augmentation is an integral step when training machine learning models and often astronomers add augmentations assuming they will always improve the performance of their models. We train multiple versions of the same pre-existing Zoobot model using different image augmentations and different
dataset sizes from 230,000
galaxy images from
Galaxy Zoo DECaLS to determine whether this assumption is necessarily true. We find that generally, the addition of image augmentations does improve a deep neural network's performance, however, this improvement is significantly diminished as the training
dataset size increases. The choice of specific augmentations (provided they are sensible) does not seem to be as important as simply having augmentations as different augmentations result in similar increases in performances. We find that for a model of a given size, there exists a saturation point (when the model's capacity has been filled with data) that cannot be surpassed with data augmentations. We find that more complex augmentations result in longer training times and might not lead to improved performance. If augmentations are added to the training process (which is recommended), simpler augmentations might be sufficient, depending on the size of the
dataset and model. We therefore encourage astronomers to carefully consider their use of image augmentations in an effort to reduce wasted time and computational resources.
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Cosmology and Nongalactic Astrophysics · Cross-listed from gr-qc
Bouncing cosmologies from Born-Infeld-type gravity
Yermek Aldabergenov, Wei Lin, Rongjian Li et al. (+2 more)
We construct a Born-Infeld-type $f(R,{\cal G})$ modification of
gravity, where ${\cal G}$ is the Gauss-Bonnet term, by
embedding Born-Infeld electrodynamics in a five-dimensional pure modified
gravity. This method leads to the correspondence between
curvature scalars and electromagnetic field strength scalars – $R\leftrightarrow F_{\mu\nu}F^{\mu\nu}$ and ${\cal G}\leftrightarrow (\epsilon_{\mu\nu\rho\sigma}F^{\mu\nu}F^{\rho\sigma})^2$ – allowing us to replicate the structure of Born-Infeld electrodynamics in the gravitational sector. The resulting Born-Infeld-type
gravity is a ghost-free $f(R,{\cal G})$ theory which reduces to Einstein
gravity in the low energy limit. In this work we focus on bouncing cosmological solutions of such a theory, which require positive spatial
curvature. By using both the Jordan and Einstein frame analyses, we find a vast space of bouncing solutions with different asymptotic behaviors, including solutions with multiple bounces grouped together. Observational consequences of such solutions will be investigated in the future.
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All authors Yermek Aldabergenov, Wei Lin, Rongjian Li, Ding Ding, Yidun Wan
Earth and Planetary Astrophysics
A Monte Carlo method for tracking dust properties during coagulation in protoplanetary disks
Nerea Gurrutxaga, Vignesh Vaikundaraman and Joanna Drazkowska
Dust growth is a crucial step in
planet formation, and the efficiency of this process is controlled by the physical and chemical properties of the
dust grains. Monte Carlo-based methods are commonly used to follow the collisional
evolution of
dust while tracking their properties. However, current Monte Carlo methods in
planet formation do not strictly conserve the global inventory of
dust properties across the protoplanetary disk, causing fluctuations that can grow over time and affect predictions of
dust evolution. Here we present a coagulation
algorithm that ensures the global conservation of
dust properties while resolving the spatial
evolution of
dust. The method is validated against analytical solutions for standard coagulation kernels and benchmarked in a two-dimensional disk. We show that the method reproduces standard results, resolves the full
dust population, and improves the resolution of the small-grain regime compared to other Monte Carlo methods for modeling global
dust evolution. Finally, using a test case that includes sublimation and condensation of water interacting with silicates, we demonstrate strict conservation of each component's mass during coagulation, establishing the method as a valuable tool for tracking
dust properties in protoplanetary disks.
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Astrophysics of Galaxies
The Bulge Cluster Origin (BulCO) survey with CRIRES at the ESO-VLT: a chemical screening of the Globular Cluster NGC 6553
A. Bartolomei, L. Origlia, C. Fanelli et al. (+10 more)
In this paper we present the chemical screening of the
stellar population belonging to the globular cluster NGC 6553 in the
Galactic bulge. This study has been conducted in the contest of the Bulge Cluster Origin (BulCO) survey, an ESO-VLT Large Program currently ongoing with CRIRES in the NIR domain. This survey is performing an unprecedented chemical screening of 17
stellar systems orbiting the Milky Way bulge, with the aim of unveiling their origin and true nature. Here we present and discuss the abundances of 18 elements produced via distinct nucleosynthetic channels for 14 red
giant branch
stars belonging to NGC 6553. We found a mean [Fe/H] = -0.20 $\pm$ 0.01 dex, and about
solar-scaled iron-peak elements, confirming that this is one of the most metal-rich globular clusters in the Milky Way. We also found [X/Fe] enhancement of $\alpha$ and several other light elements. Furthermore, we assess the presence of multiple populations typical of genuine globular clusters from the significant spreads in Na, N, and C, and an almost vertical Na-O anti-correlation. Finally, by using classical ([$\alpha$/Fe] vs [Fe/H]) and newly-defined ([V/Fe] and [Zn/Fe] vs [Fe/H]) "chemical DNA tests", we prove its in-situ formation within the
Galactic bulge.
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All authors A. Bartolomei, L. Origlia, C. Fanelli, L. Chiappino, F. R. Ferraro, B. Lanzoni, C. Pallanca, M. Loriga, M. Cadelano, D. Romano, E. Dalessandro, D. Massari, E. Valenti
Astrophysics of Galaxies
Multi-component, axisymmetric dynamical models of dSphs based on distribution functions: inferences on dark matter and intermediate-mass black holes in Draco and Ursa Minor
R. Pascale, G. Battaglia, J.M. Arroyo-Polonio et al. (+3 more)
Dwarf spheroidal
galaxies (dSphs) are
prime laboratories for studying dark matter (DM) and the black hole demographics in the low-mass regime. These systems are also often flattened; nevertheless most studies rely on spherical models, potentially affecting dynamical inferences. We introduce the first multi-component, axisymmetric dynamical models of dSphs based on distribution functions and apply them to the Milky Way dSphs Draco and Ursa Minor. The
stellar distribution is described by chemo-dynamically distinct axisymmetric populations tracing a spherical potential generated by a dominant DM
halo and a central intermediate-mass BH (IMBH). The models are fitted to discrete
stellar data from a
Gaia-based astrometric sample and two spectroscopic
datasets providing line-of-sight velocities and
metallicities, testing robustness across samples. We compare the DM properties under different modelling assumptions, including flattened one- and spherical two-component models. Both
galaxies are better described by two
stellar populations: a metal-rich, kinematically colder and concentrated component, and a more extended metal-poor one with hotter kinematics. We detect weak rotation, dynamically unimportant and ignored in the models. We measure a cuspy DM density profile in Draco ($\gamma=0.98_{-0.26}^{+0.28}$), and a more cored distribution ($\gamma=0.37_{-0.24}^{+0.31}$) for Ursa Minor. The DM
halo of Draco remains stable across all models and
datasets, making it the most robustly determined in the Local Group and highly relevant for indirect DM searches. We show that modelling flattened systems with spherical models can bias the DM inner slope towards cuspier values, while we find no degeneracy between inner
halo density and inclination. We find no evidence for IMBHs and place upper limits on their masses, $\log M_{\rm BH}[M_{\odot}] < 5.2$ for Draco and $< 3.33$ for Ursa Minor (95% confidence).
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All authors R. Pascale, G. Battaglia, J.M. Arroyo-Polonio, E. Vasiliev, C. Nipoti, G.F. Thomas
Astrophysics of Galaxies
Galactic tides and the outer density profile of the Sculptor and Ursa Minor dwarf spheroidals
Daniel A. Boyea, Julio F. Navarro, Jaclyn Jensen et al. (+1 more)
Most
dwarf spheroidal (dSph) satellites of the Milky Way follow exponential surface density profiles that decline sharply in the outer regions. The Sculptor (Scl) and Ursa Minor (UMi) dSphs deviate from this trend and show a clear excess of
stars in the outskirts. Individual members have recently been identified as far as ${\sim}10$ effective radii from the center in both systems. We study whether far-outlying
stars in Scl and UMi may result from
Galactic tidal forces using idealized N-body simulations. Our results indicate that, on their current orbits, neither
galaxy has experienced
tidal forces sufficient to affect its
stellar density profile. The observed velocity dispersion and size of Scl and UMi imply the
dwarfs are simply too dense to have been affected by
Galactic tides. We also find weak
tidal evolution when including the effects of the Large Magellanic Cloud, which our simulations suggest substantially perturbed Scl's orbit during a close encounter. Our results are insensitive to assumptions about the detailed dark matter density profile of either
galaxy, including the presence of an inner core. We conclude that the outlying
stars in Scl or UMi are not of
tidal origin, but rather innate features that possibly reflect past merger events or the presence of multiple dynamical components.
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All authors Daniel A. Boyea, Julio F. Navarro, Jaclyn Jensen, Raphaël Errani
Cosmology and Nongalactic Astrophysics
Cosmic gas accretion from filaments onto galaxy clusters using the IllustrisTNG simulation
Jade Pasté, Céline Gouin, Nabila Aghanim et al. (+1 more)
Galaxy clusters grow through the matter
accretion from the
cosmic web, mainly along filaments. We aim to characterize the gas
accretion onto clusters, focusing on the role of filaments in driving anisotropic inflows and thermodynamic properties, as it remains a key challenge for cosmology. In this study, we analyzed 415
galaxy clusters from the IllustrisTNG-300 hydrodynamical simulation at $z=0$. Anisotropic signatures are highlighted by probing both isotropically and anisotropically (gas in filaments only), the radial profiles of gas properties (including temperature,
entropy, density, and pressure), and the radial velocity distributions. Our results highlight two distinct regimes of gas
accretion depending on the cluster-centric distances. In the cluster environment ($\sim$ 2-4$R_{200}$), fast infalling warm gas tunneled by
cosmic filaments enters the warm-hot circumcluster medium, but filaments remain colder due to their slow thermalization with the surrounding, generating transverse temperature gradients. At the cluster outskirts ($\sim$ 1-2$R_{200}$), gas infalling along filaments enters the hot intracluster medium, with a strong tangential velocity gradient. Warm gas tends to penetrate clusters from filaments, while hot gas is preferentially ejected beyond them. The mass and dynamical state of clusters significantly impact these
accretion features, with relaxed and massive clusters exhibiting stronger and more extended temperature discontinuities. Overall, this work emphasizes a coherent picture of anisotropic gas
accretion from filaments onto clusters. While virial shocks tend to be observed near the cluster boundary, especially at the filament-cluster interface. We do not find strong evidence of
accretion shocks around filaments, suggesting slow thermalization of filament gas as it enters the dense warm-hot circum-cluster environment.
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All authors Jade Pasté, Céline Gouin, Nabila Aghanim, Jenny G. Sorce
Astrophysics of Galaxies
SN Ia Population Machine. I. A Unified Cosmological Simulation-Binary Synthesis Framework Establishing Non-universal Delay-time Distributions and Cosmic Progenitor-channel Dominance Crossover
Suk-Jin Yoon, Inhyuk Park, Woong-Bae G. Zee et al. (+6 more)
We present a forward-modeling framework for synthesizing Type Ia
supernova (SN Ia) populations by coupling cosmological hydrodynamic simulations to binary population synthesis (BPS). Using IllustrisTNG
star particles as simple
stellar populations, we generate binaries and evolve them with COMPAS to produce synthetic SNe Ia tagged with explosion times and progenitor channels (single- and double-degenerate; SD and DD). This cosmology-BPS pipeline enables self-consistent, end-to-end tracking of SN Ia populations from individual
galaxies to
cosmic scales. The model reproduces key SN-related observables, including host-
galaxy demographics, delay-time distributions (DTDs), SN-rate trends with host properties and
redshift, and a progenitor-age 'step' implicated by the mass step in Hubble residuals. Our main findings are as follows. (1) Contrary to the standard assumption, DTDs appear intrinsically non-universal: their form depends on progenitor channel and
metallicity, and thus varies systematically across hosts and with
redshift. The commonly adopted DTD is therefore best regarded as a population-averaged approximation rather than a fundamental kernel. (2) We predict that the dominant SN Ia progenitor population shifts from SD to DD with
cosmic time, with a demographic crossover near z = 0.5 (~5.2 Gyr ago). This non-monolithic SN Ia population with a
redshift-dependent SD/DD mixture weakens the universality implicit in a single globally calibrated standardization. Taken together,
evolution in both the DTD and the channel mixture can imprint
redshift-dependent systematics on SN Ia luminosities, strengthening the case for jointly inferring progenitor/host-driven effects alongside
cosmic acceleration. The full catalogue and analysis scripts are available via Zenodo.
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All authors Suk-Jin Yoon, Inhyuk Park, Woong-Bae G. Zee, Chul Chung, Jun-Sung Moon, Sanjaya Paudel, Kiyun Yun, Myung-Hun Kim, Eun-Taek Gim
Earth and Planetary Astrophysics
ORCHARD: A General Planetary Evolution Code
Roberto Tejada Arevalo, Adam Burrows, Ankan Sur et al. (+1 more)
We present ORCHARD, a publicly available planetary
evolution code based on the gas
giant evolution code, APPLE, capable of modeling the
evolution and structures of terrestrial, super-Earth, sub-Neptune, Neptune, and gas
giant planets and
exoplanets from 0.5 M$_\oplus$ to 10 M$_J$. It supports not only the inhomogeneous and non-adiabatic
evolution of gas
giants and sub-Neptunes, but also the solidification of the mantles and cores of terrestrial
planets, sub-Neptunes, and super-Earths. ORCHARD incorporates a state-of-the-art hydrogen-helium equation of state, “metal" equations of state (water, ice mixtures, enstatite/perovskite, olivine/forsterite, iron), and atmospheric boundary conditions ranging from detailed non-gray radiative transfer models for
Solar System
giants to irradiated sub-Neptune atmospheres and bare rocky surfaces. \txt{ORCHARD} also supports static calculations with state-of-the-art equations of state. The purpose of ORCHARD is to provide the scientific community with a flexible, unified tool for modeling planetary structures and
evolution across the entire mass continuum of general astrophysical and planetary interest.
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All authors Roberto Tejada Arevalo, Adam Burrows, Ankan Sur, Yubo Su
Cosmology and Nongalactic Astrophysics
spectroxide: A code package for computing cosmic microwave background spectral distortions
Ethan Baker, Hongwan Liu and Siddharth Mishra-Sharma
We present spectroxide, a code package for computing
cosmic microwave background spectral distortions in which all ${\sim}14{,}500$ lines of Rust code, Python interface, and ${\sim}400$ automated tests were written by an AI assistant (Claude Code) under human physicist supervision. The solver evolves the
photon Boltzmann equation under Compton scattering, double Compton emission, and Bremsstrahlung from $z \sim 5 \times 10^6$ to the present, computing spectral distortions from arbitrary heat and
photon injection within this
redshift range. No fully open-source code of this kind is publicly available; we validate against analytic limits, published spectra, and publicly available precomputed Green's function tables. We document the development as a case study in AI-assisted scientific computing, highlighting how domain expertise caught physics bugs (incorrect dimensional prefactors, near-cancellation errors) that evaded the full automated test suite, and provide recommendations for best practices in human–AI collaborative development of scientific software. We make spectroxide publicly available on GitHub.
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Astrophysics of Galaxies
The evolution of the baryonic content and mass profiles of satellite galaxies in the MTNG simulations
Sergio Contreras, Raul E. Angulo, Giovanni Aricò et al. (+5 more)
Empirical models often rely on key relations from the
galaxy–
halo connection to construct mock
galaxy catalogues. These relations typically describe central
galaxies more accurately than satellite
galaxies, which are generally less massive and orbit within larger
haloes. Satellite
galaxies are affected by a variety of physical processes that pose significant challenges for modelling. In this work, we use \MTNG, a state-of-the-art cosmological hydrodynamic simulation, to study the
evolution of the baryonic component of satellites. Using the merger trees from this simulation, we follow the
evolution of all $z=0$ satellite
galaxies, tracking their
stellar mass, gas mass, and $r$- and $U$-band magnitudes. We characterise this
evolution using proxies including the fraction of subhalo mass and maximum circular velocity remaining relative to infall, the pericentric distance, and the time since infall. All of these quantities are commonly available in
gravity-only simulations and can therefore be used to model these trends in simpler
galaxy population models. We find that the gas mass, which is well described by the remaining subhalo mass fraction, declines much more rapidly than the other components, with satellites losing $\sim 80\%$ of their gas by the time the subhalo has lost half of its total mass. By contrast, the
evolution of
stellar mass and magnitudes is overall slower and is better described by the reduction of the host subhalo $v_{\rm max}$. We then examine the
evolution of satellite mass profiles. We find that, although stripping is strongest in the outer regions, the intermediate and inner parts of satellites experience mass loss at early times. The results of this work can be used by empirical models and
galaxy formation models built on
gravity-only simulations to improve their descriptions of satellite
galaxies.
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All authors Sergio Contreras, Raul E. Angulo, Giovanni Aricò, Lurdes Ondaro-Mallea, Sownak Bose, Lars Hernquist, Ruediger Pakmor, Volker Springel
Astrophysics of Galaxies
The Thermodynamic and Kinematic Evolution of Circumgalactic Gas around $z=1$ in the IllustrisTNG model
Daniel DeFelippis, Shy Genel and Greg L. Bryan
The circumgalactic medium (CGM) is known to contain multiphase gas in various stages of
evolution and interaction with the
galaxy. In order to characterize its detailed behavior on short timescales, we use a subregion of the TNG100 cosmological simulation to study the
evolution of the $z=1$ CGM around six
galaxies in $10^{11.5}-10^{12}$ $M_{\odot}$
halos at a high time cadence of $\approx2$ Myr. We use Monte Carlo tracer particles to follow this CGM gas forward in time in a Lagrangian way and determine how its thermodynamic and kinematic properties change. We find that CGM gas mixes between different temperature and density phases quickly and within $\approx500$ Myr evolves into distinct cold ($T\approx10^4$ $\rm{K}$) and warm-hot ($T\approx10^{5.5}$ $\rm{K}$) phases at small and large distances from the
galaxy, respectively, regardless of its initial ($z=1$)
halo-centric radius. This is largely driven by feedback from the
galaxy, which heats and ejects cold gas that had previously cooled and accreted toward and occasionally into the
galaxy from the outer CGM. We see signatures of this process in autocorrelations of kinematic quantities, which take $\approx400$ Myr to fully decorrelate from their initial values, suggesting a timescale over which feedback disrupts and reprocesses CGM gas. We also examine gas in narrow temperature and density ranges associated with commonly observed ions and find that gas that is O VI-like stays in its phase for hundreds of Myr longer than gas that is Mg II-like or C IV-like, suggesting that CGM observations of different species could probe gas in different evolutionary states, even if the gas is cospatial.
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Cosmology and Nongalactic Astrophysics
Malcolm Fairbairn, María Olalla Olea-Romacho, Juan Urrutia et al. (+1 more)
Primordial magnetic fields (PMFs) enhance small-scale structure formation through the Lorentz force acting on
baryons, boosting the abundance of low-mass
halos and their hosted
galaxies. We show that the reionisation history calibrated with the UV luminosity function (UVLF) provides stringent bounds: strong PMFs induce a characteristic double reionisation at $z \approx 24$ that is incompatible with CMB measurements of the optical depth, yielding $\sqrt{\left\langle B^2 \right\rangle} < 0.27\,{\rm nG}$ and $< 0.18\,{\rm nG}$ for $n_B = -2$ and $n_B = 2$ respectively at $95\%\,{\rm CL}$ using Planck priors on $\tau$. This establishes early
galaxy observables as among the most sensitive probes of PMFs in Gaussian, non-helical scenarios.
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All authors Malcolm Fairbairn, María Olalla Olea-Romacho, Juan Urrutia, Ville Vaskonen
Cosmology and Nongalactic Astrophysics
Cosmological Impact of Redshift-Dependent Type Ia Supernovae Calibration
Seyed Hamidreza Mirpoorian, Meng-Xiang Lin and Levon Pogosian
Type Ia
supernovae (SNIa) play a central role in constraining the late-time expansion history of the Universe and are directly implicated in current cosmological tensions. Motivated by the possibility of unaccounted
redshift-dependent calibration systematics or new physics, we investigate the impact of a phenomenological correction to SNIa magnitudes that scales with
cosmic look-back time. We parameterize this effect with a free amplitude and constrain it using a combination of
cosmic microwave background,
baryon acoustic oscillation, and SNIa data, considering both $\Lambda$CDM and dynamical dark energy models. Importantly, our parameterization is not intended to serve as a proxy for SNIa progenitor age, as current observations show no significant difference in standardized SNIa brightness between young and old progenitor populations at low
redshift. We find no evidence for a
redshift-dependent calibration effect when fitting uncalibrated SNIa data, and its inclusion has a negligible impact on cosmological parameters within $\Lambda$CDM, nor does it qualitatively change the inferred dynamics of evolving dark energy. When incorporating a prior on the SNIa absolute magnitude from SH0ES, a nonzero calibration parameter is weakly preferred within $\Lambda$CDM. Interestingly, with dynamical dark energy, the preference of a nonzero calibration parameter increases to $4.3\sigma$, and it can accommodate both the distance ladder and early-Universe constraints, reducing the Hubble tension to $1.5\sigma$, with the best-fit model effectively corresponding to a constant equation of state with $w < -1$. Overall, our results indicate that
redshift-dependent SNIa calibration effects, as parameterized here, are not supported by current data within $\Lambda$CDM, but can play a role in reconciling cosmological
datasets when combined with extensions to the late-time expansion history.
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Astrophysics of Galaxies
The lifetime of 100,000 molecular clouds in the nearby Universe
Z. Bazzi, M. I. N. Kobayashi, D. Colombo et al. (+25 more)
Multiple mechanisms are proposed for the formation of
giant molecular clouds (GMCs), from gravitational free-fall caused by self-
gravity to
stellar feedback-driven gas compression. Both the
galactic environment and
galaxy conditions could play an additional role in enhancing the formation via their gas surface density and
star formation activity. In this paper, we make use of a catalog of 108,466 GMCs identified by F770W PHANGS–JWST imaging across 66
galaxies at a homogenized resolution of 30~pc. We measure the mass spectra in various
galactic regions, whose power-law slopes vary from $-1.2$ to $-2.0$. We then estimate the formation time of each cloud using a model where GMCs form from multiple feedback compression, and find that clouds with masses $\leq 10^{5}\,M_{\odot}$ form, on average, in 20~Myr, with more massive clouds ($\sim 10^{6}$–$10^{7}\,M_{\odot}$) taking up to 100~Myr. We also find that cloud formation proceeds most rapidly in the central regions of
galaxies, with formation timescales that are typically shorter by $\sim 5$–$10$~Myr compared to
galactic disks. This effect is most pronounced in central molecular zones with enhanced
star formation, highlighting the role of intense massive
star formation, high molecular gas surface densities, and strong supersonic compressions in accelerating cloud formation. However,
star formation is generally inefficient as the cloud lifetime is $\sim 1\,\%$ of the molecular depletion time. The formation time of clouds is $\sim 0.1$~dex longer than the free-fall time. This hints that
magnetic fields,
stellar feedback, or other mechanisms may prolong their formation instead of immediate free-fall collapse. This indicates a longevity of massive GMCs. The GMC ages also show only limited variation with galactocentric radius in both spiral and disk
galaxies, suggesting that cloud formation proceeds similarly in these
galaxy types.
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All authors Z. Bazzi, M. I. N. Kobayashi, D. Colombo, F. Bigiel, A. K. Leroy, S. E. Meidt, R. S. Klessen, E. Rosolowsky, R. Chown, D. A. Dale, S. Dlamini, M. Greve, S. K. Stuber, M. Boquien, T. G. Williams, H.-A. Pan, M. Querejeta, L. Ramambason, A. Romanelli, T. Saito, L. E. C. Romano, M. J. Jiménez-Donaire, H. Kim, D. Pathak, H. Koziol, J.Sutter, J.C. Lee, the PHANGS collaboration
Astrophysics of Galaxies
Connecting the dusty dots: dust depletion and extinction of local interstellar clouds
T. Ramburuth-Hurt, A. De Cia, J.-K. Krogager et al. (+2 more)
Investigating the chemical complexity of the interstellar medium (ISM) is key for understanding its physical nature and
evolution. In this work, we study parsec-scale interstellar
dust clouds in the neutral ISM of the Milky Way using two different probes:
dust depletion and
dust extinction. We examine their relationship to investigate the distribution of metals and
dust in the
Solar neighbourhood, and how they are related to the Local Bubble. We use measurements of
dust depletion for individual gas clouds along sight lines of sight towards bright O/B
stars within 1.1 kpc of the Sun, derived from UV absorption-line spectra. We combine these with parsec-scale 3D
dust extinction density maps out to 1.25 kpc. We assume a correlation between
dust depletion and
dust extinction density, which we use to imply that the absorption components are spatially associated with the peaks in
dust extinction density, and to pinpoint the likely locations of the gas clouds in physical space. We identify peaks in the
dust extinction curves, and then associate the stronger peaks with the strongest
dust depletion components. Independent distance measurements along the line of sight towards one of our targets, theta1 Ori C, validates our results. In our sample, the minimum distance between clouds that have significantly different chemical properties is ~ 100pc, giving an indication on the physical scale on which chemical mixing remains incomplete in the ISM of the Milky Way. For five of the eight targets, we report
dust depletion values for gas clouds associated with the Local Bubble. Additionally, we find a velocity gradient that is consistent with the expansion of the Local Bubble, further supporting our methodology. Overall, we show that it is possible to use complementary information from
dust depletion and
dust extinction to build more detailed maps of ISM metal and
dust distributions.
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All authors T. Ramburuth-Hurt, A. De Cia, J.-K. Krogager, C. Ledoux, A. J. Fox
High Energy Astrophysical Phenomena
Spectral Evidence of Heavy Nuclei from the Neutron Star Crust in Magnetar Bursts
Sheng-Lun Xie, Yun-Wei Yu, Shao-Lin Xiong et al. (+1 more)
The crust of a
neutron star (NS) provides a unique laboratory for studying matter under extreme density and
magnetic field conditions that cannot be realized in terrestrial experiments. However, direct observational constraints on its composition have remained very limited. Magnetar bursts provide a promising means to probe the
nuclear composition of the outer crust, as their energy release may be associated with stress-driven yielding of the crustal Coulomb
lattice (including plastic deformation) and
magnetic reconnection in the surrounding magnetosphere. We develop a general-purpose radiative transfer framework for a strongly magnetized electron–ion thermal
plasma (MEITP) and apply it to the observed X-ray burst spectra. The spectral fits disfavor light-ion compositions and instead favor
plasmas characterized by effective charge numbers around $Z \sim 37$. These results provide spectral evidence for the participation of heavy
nuclei in magnetar bursts, offer new observational constraints on the baryonic content and the location of the emitting fireballs, and further imply a crustal origin of the heavy ions.
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All authors Sheng-Lun Xie, Yun-Wei Yu, Shao-Lin Xiong, Wang-Chen Xue
Solar and Stellar Astrophysics
Analysis of the Gaia DR3 planetary nebula candidates and the possible symbiotic stars among them
Lionel Mulato, Jaroslav Merc, Stéphane Charbonnel et al. (+3 more)
The
Gaia DR3, released in June 2022, included low-resolution BP/RP (XP) spectra that have been exploited for the classification of various types of emission-line objects using machine-learning techniques. The
Gaia Extended
Stellar Parametrizer for Emission-Line
Stars (ESP-ELS)
algorithm identified 273 sources as potential planetary nebulae (PNe). We aim to analyze the PN sample produced by the ESP-ELS
algorithm to investigate the true nature of the objects classified as PNe. We extracted all sources from the catalog classified as PNe by the ESP-ELS
algorithm and filtered out 200 objects with secure classifications available in the literature. Of these, $\sim$65% correspond to known
Galactic or Magellanic compact PNe, and $\sim$20% to D- or D'-type symbiotic systems. The XP spectra of the remaining sources were visually inspected, leading to a subset of 14 promising candidates showing strong emission features attributable to H$\alpha$ and [O III] $\lambda$5007. Although typical of PNe, such features are also consistent with D- or D'-type symbiotics, known to mimic compact PNe. We obtained spectroscopic follow-up observations for these objects with the 2SPOT facilities in Chile and France, complemented by an analysis of archival photometric data to further constrain their nature. We report the identification of nine bona-fide or likely D- or D'-type symbiotic systems, one planetary nebula in the LMC, one polar cataclysmic variable, and three possible Be
stars in (or in the direction of) the SMC, within our sample of 14 objects.
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All authors Lionel Mulato, Jaroslav Merc, Stéphane Charbonnel, Olivier Garde, Pascal le Dû, Thomas Petit
Astrophysics of Galaxies
Dynamical Modeling of the Broad-Line Region with High-Mass Active Galactic Nuclei and Constraints on the Virial Factor
Shu Wang, Jong-Hak Woo, Lizvette Villafaña et al. (+2 more)
We present the results of broad-line region (BLR) dynamical modeling for eight high-mass active
galactic nuclei (AGNs) from the Seoul National University AGN Monitoring Project, by constraining BLR geometry and kinematics as well as black hole (BH) mass ($M_{\rm BH}$). We find that the H$\beta$-emitting BLRs are best described as thick disks viewed at intermediate inclinations, with emission preferentially originating from the far side of the BLR. BLR kinematics show a combination of rotational, inflowing and outflowing components. By comparing the $M_{\rm BH}$ from dynamical modeling with the virial products based on reverberation lags and line widths, we determine the virial factor $f$ for individual AGNs. Combining our sample with those $M_{\rm BH}$ consistently determined from BLR dynamical modeling, yielding a total of 38 objects, we derive a virial factor for future $M_{\rm BH}$ estimation of log$_{10}({f})_{\rm pred}=0.69\pm0.21$ based on $\sigma_{\rm line,rms}$ and $-0.08\pm0.23$ based on FWHM$_{\rm mean}$. The derived virial factor is consistent with that inferred by aligning the reverberation-mapped AGNs with quiescent
galaxies in the $M_{\rm BH}$-$\sigma_{\ast}$relation, supporting the assumption that local active and inactive
galaxies follow the same $M_{\rm BH}$-$\sigma_{\ast}$ relation. Our updated $f$ values exhibit an intrinsic dispersion of $\sim0.2$ dex, which allows for a more precise $M_{\rm BH}$ estimates than those based on the $M_{\rm BH}$-$\sigma_{\ast}$ relation. Our sample extends the dynamical modeling-based reverberation sample to $M_{\rm BH}$ $\sim$ [$10^8$, $10^{8.5}$] $M_{\odot}$ range, where the virial factor from the the AGN $M_{\rm BH}$-$\sigma_{\ast}$ relation remains poorly constrained, underscoring the unique value of dynamical modeling analysis in constraining the $M_{\rm BH}$ of the most massive BHs.
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All authors Shu Wang, Jong-Hak Woo, Lizvette Villafaña, Tommaso Treu, Elena Gallo
Astrophysics of Galaxies
Halfway to the Peak: Kinematic Signatures of Stable Rotating Disks in Luminous Infrared Galaxies at z=0.5-0.6
Miriam Eleazer, Alexandra Pope, Anna Sajina et al. (+13 more)
We present a kinematic study of six infrared-luminous
galaxies observed with the Mid-InfraRed Instrument Medium-Resolution Spectrometer (MIRI/MRS) onboard JWST. These
galaxies lie at $z = 0.5$–$0.6$, midway between the present day and the peak of
cosmic star formation. Our sample spans a range of
star formation (SF) and active
galactic nucleus (AGN) contributions to the mid-infrared emission. We characterize the dynamical state of these IR-luminous
galaxies and assess how AGN activity influences the kinematics of the interstellar medium. Using mid-IR atomic lines, we map
galaxy kinematics beyond the local Universe for the first time. The spatial resolution of MIRI/MRS (3.0 kpc for 0.46$\arcsec$ at z $\sim$ 0.55) allows us to resolve the internal kinematics of our targets. We compute kinematic maps in three different emission lines ([Ar II]6.99$\mu$m, [Ne II]12.81$\mu$m, and H$_2$ 0-0 S(5)6.91$\mu$m). Using the [Ar II]6.99$\mu$m kinematic maps, we derive rotation curves for these sources. All
galaxies exhibit ordered rotation, with \(V/\sigma \geq 2\), consistent with stable disks. Although some show minor disturbances, we find no strong evidence for recent major mergers or
galaxy-wide ionized
outflows. We find no correlation between \(V/\sigma\) and AGN fraction, suggesting AGN activity does not significantly disrupt global kinematics or that disk disruption is not required to trigger AGN. However,
galaxies with higher AGN fractions show elevated central dispersions, indicating localized
turbulence, possibly due to AGN feedback,
stellar feedback,
accretion or bulge structure. These IR-luminous
galaxies likely represent mature, rotationally supported disks, with AGN activation occurring after disk assembly.
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All authors Miriam Eleazer, Alexandra Pope, Anna Sajina, Lin Yan, Jason Young, Stacey Alberts, Lee Armus, Kristen Coppin, Daniel Dale, Duncan Farrah, Thiago Gonçalves, Jed McKinney, Nicole Nesvadba, Patrick Ogle, Roxana Popescu, Sylvain Veilleux
Cosmology and Nongalactic Astrophysics
SWIM: Stochastic Warm Inflation Module to generate and analyse Warm Inflationary power spectrum
Umang Kumar and Suratna Das
Numerical analysis to determine the form of the scalar power spectrum in Warm Inflationary paradigm is inevitable. One further needs numerical techniques to analyse any Warm Inflation model with the current observational data through the MCMC codes that are available publicly, like COSMOMC or Cobaya. We present SWIM (
Stochastic Warm Inflation Module) written in C++ and Python, that not only helps generate the Warm Inflationary scalar power spectrum, either semi-analytically or fully numerically, but also is integrated with Cobaya enabling the user to constrain the model parameters with current CMB data and thus to put any Warm Inflation model to test. SWIM numerically solves the standard
stochastic perturbation equations of Warm Inflation without any approximations, uses machine learning techniques to speed up the MCMC analysis while analysing the fully numerical power spectrum that significantly reduces the computational cost, and is able to accommodate any Warm Inflation model with any form of inflationary potential and dissipative coefficient for numerical analysis. We show that SWIM, in most of the cases, outperforms other numerical codes on Warm Inflation that are designed to yield only the semi-analytical power spectrum as far as the runtimes are concerned. We further point out that there can be situations where the semi-analytical way of determining the scalar power spectrum in Warm Inflation can fall short, and one needs the full numerical power spectrum for parameter estimation given the observational data. In such cases, SWIM is the only code available so far that is designed to perform the task. Hence, SWIM offers a complete numerical platform for thorough analysis of Warm Inflation models against the current cosmological data. SWIM has been made publicly available at https://github.com/umg-kmr/SWIM.
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Cosmology and Nongalactic Astrophysics
Measurement of the Weyl Potential Evolution and $E_G$ Statistic from KiDS-1000, BOSS and 2dFLenS
Xuwei Zhang, Ming Zhang, Yunliang Ren et al. (+1 more)
A recently developed model-independent approach to measuring the Weyl potential has shown some tensions with $\Lambda$CDM (Lambda Cold Dark Matter) in DES (Dark Energy Survey) Y3 data. We apply this framework to Kilo-Degree Survey (KiDS-1000) weak
lensing and BOSS/2dFLenS
galaxy clustering using the KiDS Cosmology Analysis Pipeline (KCAP) in two
redshift bins. To apply this method to the BOSS spectroscopic wedges, we take the early-time power spectrum from a
redshift where General Relativity (GR) is recovered and jointly fit the late-time observables $\hat{b}$, $\hat{f}$, and $\hat{J}$. With Planck18 priors, the CMASS measurement of $\hat{J}$ is $1.50\sigma$ below the GR prediction, while the LOWZ measurement remains consistent with it. The decrease in the central value of $\hat{J}$ from LOWZ to CMASS provides a mild indication of the previously reported “
Lensing is low” behavior. Without Planck18 priors, we obtain $E_G(0.38)=0.503\pm0.054$ and $E_G(0.61)=0.444\pm0.054$, both consistent with GR. Furthermore, phenomenological
gravity tests also show no significant preference for modified
gravity.
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All authors Xuwei Zhang, Ming Zhang, Yunliang Ren, Xiaofeng Yang