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In: arXiv

Multi-field TDiff theories: the mixed regime case Antonio L. Maroto, Prado Mart’in-Moruno, Diego Tessainer arXiv:2507.16616v2 Announce Type: replace-cross Abstract: We study theories breaking diffeomorphism (Diff) invariance down to the subgroup of transverse diffeomorphisms (TDiff), consisting of multiple scalar fields in a cosmological background. In particular, we focus on models involving a field dominated by its kinetic term and a field dominated by its potential, coupled to gravity through power-law functions of the metric determinant. The Diff symmetry breaking results in the individual energy-momentum tensors not being conserved, although the total conservation-law is satisfied. Consequently, an energy exchange takes place between the fields, acting as anRead More →

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In: arXiv

GSE vs. LMC: reshaping of radially biased stellar haloes by satellites Adam M. Dillamore, Jason L. Sanders, Richard A. N. Brooks arXiv:2603.11159v1 Announce Type: new Abstract: Perturbations from the Large Magellanic Cloud (LMC) of the Milky Way’s stellar and dark matter haloes are well-established. However, studies have generally not considered haloes with high radial anisotropy, like debris from the Gaia Sausage-Enceladus (GSE) in the Milky Way. We run a series of test particle simulations of stellar haloes with different velocity anisotropies $betain[0.5,0.9]$. The LMC causes these initially axisymmetric haloes to become approximately triaxial. Their major axes are aligned with its orbital plane and tilted byRead More →

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In: arXiv

Orbital Dynamics and Gravitational Wave Signatures of Extreme Mass Ratio Inspirals in Galactic Dark Matter Halos Guo-He Li, Chen-Kai Qiao, Jun Tao arXiv:2603.02414v2 Announce Type: replace-cross Abstract: In astrophysics, extreme mass ratio inspiral (EMRI) systems, which consist of a central supermassive black hole and a stellar-mass compact object (SCO), are typically embedded in galactic dark matter (DM) halos. This dark matter environment inevitably affects the orbital dynamics of the SCO and the gravitational wave (GW) signals emitted by the system. In this work, we select two typical dark matter halo profiles — the Navarro-Frenk-White (NFW) and Beta models — to systematically investigate their specific impactsRead More →

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In: arXiv

The TRGB-SBF Project. IV. A Color Calibration of the TRGB in the JWST F090W+F150W Filters Maksim I. Chazov, Dmitry I. Makarov, R. Brent Tully, Gagandeep S. Anand, Lidia N. Makarova, Yotam Cohen, John P. Blakeslee, Michele Cantiello, Joseph B. Jensen, Gabriella Raimondo arXiv:2603.11160v1 Announce Type: new Abstract: Observations with JWST in the F090W band provide a powerful tool for determining galaxy distances based on tip of the red giant branch (TRGB) measurements. It is a great convenience that the TRGB lies at an almost constant absolute magnitude level at low metallicities. However, the TRGB becomes fainter at high metallicities in the F090W filter. Details ofRead More →

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In: arXiv

The shocking features in the closest rich galaxy cluster Norma Chong Ge, Ming Sun, Mpati Ramatsoku, Chris Nolting, B"arbel S. Koribalski arXiv:2603.12082v1 Announce Type: new Abstract: The merger shocks generated by the collision of galaxy clusters elevate the pressure within the intracluster medium, significantly influencing the evolution of embedded cluster galaxies. We detect a merger shock (Mach number $sim 1.3$) on the northwest side of the closest rich galaxy cluster Norma (A3627), using XMM-Newton and Chandra data. The textbook ram pressure stripping (RPS) galaxy ESO 137-001 appears to be located in the post-shock region. The shock boosts RPS and may induce the formation of theRead More →

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In: arXiv

FlowSN: Normalising Flows for Simulation-Based Inference under Realistic Selection Effects applied to Supernova Cosmology Benjamin M. Boyd, Kaisey S. Mandel, Matthew Grayling, Ayan Mitra, Richard Kessler, Maximilian Autenrieth, Aaron Do, Madeleine Ginolin, Lisa Kelsey, Gautham Narayan, Matthew O’Callaghan, Nikhil Sarin, Stephen Thorp arXiv:2603.11165v1 Announce Type: new Abstract: We present FlowSN, a statistical framework using simulation-based inference with normalising flows to account for selection effects in observational astronomy. Failure to account for selection effects can lead to biased inference on global parameters. An example is Malmquist bias, where detection limits result in a sample skewed towards brighter objects. In Type Ia supernova (SN Ia) cosmology, theseRead More →

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In: arXiv

Comparing the $M_{gas}-N_{yso}$ Relation inside a Giant Molecular Cloud Carlos G. Rom’an-Z’u~niga (Instituto de Astronom’ia UNAM Mexico), Aina Palau (Instituto de Radioastronom’ia y Astrof’isica UNAM Mexico), Javier Ballesteros-Paredes (Instituto de Radioastronom’ia y Astrof’isica UNAM Mexico), Manuel Zamora-Avil’es (Instituto Nacional de Astrof’isica ‘Optica y Electr’onica Mexico), Joshua Peltonen (Department of Physics University of Alberta Canada), Karla Guti’errez-Davila (Instituto de Radioastronom’ia y Astrof’isica UNAM Mexico) arXiv:2603.12212v1 Announce Type: new Abstract: In this paper we present a simple analysis around scaling relations derived from the Schmidt conjecture for star-forming molecular clouds, at the intra-cloud scale. Using a hierarchical tree (dendrograms) above a constant threshold ($A_V$ = 7 mag),Read More →

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In: arXiv

Isophote shape analysis and the unfortunate subtlety of dwarf galaxy structure A. E. Watkins, I. Lazar, T. Sedgwick, G. Martin, S. Kaviraj, D. Kakkad, C. Collins, B. Bichang’a arXiv:2603.11166v1 Announce Type: new Abstract: Dwarf galaxies ($M_{*}/M_{odot} lesssim 10^{9.5}$), being sensitive to key evolutionary drivers like baryonic feedback and tidal perturbation, are crucial for understanding galaxy evolution as a whole. Their abundance and faintness, however, ensures that most will be studied primarily via broadband imaging for the foreseeable future. It is thus crucial to identify the most informative broadband-derivable quantities in the dwarf regime. As studies of widely used morphological parameters like concentration, asymmetry, and smoothnessRead More →

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In: arXiv

Phase Retrieval using Nonlinear Curvature Sensing within Convergent Beams Justin R. Crepp, Caleb G. Abbott, James Smous, Matthew Engstrom, Brian Sands arXiv:2603.11832v1 Announce Type: cross Abstract: Path-length diversity methods may be used for adaptive optics (AO) systems to retrieve phase and amplitude information by measuring intensity across multiple planes. Observations that rely on free-space propagation, such as the nonlinear curvature wavefront sensor (WFS), have been shown to offer excellent sensitivity and robustness to scintillation. However, the default design results in a large opto-mechanical footprint due to unavoidable geometric-optics and wave-optics effects. Measurements recorded in a convergent beam would improve instrument compactness, while concentrating light intoRead More →

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In: arXiv

Gravitational Wave Measurement of the Mbh-Mbulge Intrinsic Scatter at High Redshift Cayenne Matt, Kayhan G"ultekin, Gabriella Agazie, Nikita Agarwal, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Jeremy G. Baier, Paul T. Baker, Bence B’ecsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, Robin Case, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. DeCesar, Paul B. Demorest, Heling Deng, Lankeswar Dey, Timothy Dolch, Graham M. Doskoch, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Emiko C. Gardiner, Nate Garver-Daniels, Peter A. Gentile, Kyle A. Gersbach,Read More →

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In: arXiv

Novel density profile for isothermal cores of dark matter halos Vinh Tran, Xuejian Shen, Mark Vogelsberger, Daniel Gilman, Stephanie O’Neil, Cian Roche, Oliver Zier, Jiarun Gao arXiv:2411.11945v4 Announce Type: replace Abstract: We present a novel analytic density profile for halos in self-interacting dark matter (SIDM) models, which accurately captures the isothermal-core configuration, i.e. where both the density and velocity dispersion profiles exhibit central plateaus in the halo innermost region. Importantly, the profile retains a simple and tractable functional form. We demonstrate analytically how our density profile satisfies the aforementioned conditions, with comparisons to other contemporary functional choices. We further validate the profile using idealized N-bodyRead More →

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In: arXiv

Large-scale environments of star-forming active galactic nuclei: How black hole mass, accretion rate, and luminosity connect to dark matter halos G. Mountrichas, F. J. Carrera, F. Shankar, A. Georgakakis arXiv:2603.11169v1 Announce Type: new Abstract: Understanding the relative roles of large-scale environment and internal host-galaxy processes in shaping AGN activity is essential for constraining models of black-hole growth and galaxy evolution. We investigate how the environment of X-ray selected active galactic nuclei (AGN) relates to black-hole growth and accretion properties, and whether these introduce an environmental dependence beyond that expected from the host galaxy itself. Combining the XXL and Stripe 82X surveys, we construct samples ofRead More →

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In: arXiv

Atmospheric Characterisation with the Twinkle Space Telescope Following Advances from JWST Observations Tailong Zhang, Benjamin Wilcock, Sushuang Ma, Giovanna Tinetti, Lawrence Bradley, Ian Stotesbury, Marcell Tessenyi, Jonathan Tennyson arXiv:2508.10386v2 Announce Type: replace Abstract: The Twinkle Space Telescope is a satellite designed for spectroscopic observations of a wide range of extrasolar and solar system objects. Equipped with a 0.45 m diameter telescope and a spectrometer covering from 0.5 to 4.5 {mu}m simultaneously, Twinkle will be launched in a sun-synchronous, low-Earth orbit, and it is expected to operate for seven years. Twinkle is developed, managed and operated by Blue Skies Space (BSSL), a space science data companyRead More →

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In: arXiv

Long GRB 250916A: an Off-axis Powerlaw Jet with Thermal Cocoon Utkarsh Pathak (Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India), Sameer K. Patil (Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India), Hitesh Tanenia (Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India), Tanishk Mohan (Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India), Xander J. Hall (McWilliams Center for Cosmology and Astrophysics, Department of Physics, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA), Yogesh Wagh (Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India), Viswajeet SwainRead More →

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In: arXiv

Stellar Cores Live Long and Prosper in Cuspy Dark Matter Halos Jenni H"akkinen (University of Helsinki), Alexander Rawlings (University of Helsinki, Max-Planck-Institut f"ur Astrophysik), Till Sawala (University of Helsinki), Matthew G. Walker (Carnegie Mellon University) arXiv:2512.05719v2 Announce Type: replace Abstract: The existence of cuspy or cored centers of dark matter halos is a crucial discriminant between different dark matter models. It has recently been claimed based on dynamical arguments that perfectly cored stellar systems cannot survive inside cuspy dark matter halos, which would make the observation of stellar cores in ultrafaint dwarf galaxies, where dark matter cores cannot form through baryonic processes, a direct falsificationRead More →

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In: arXiv

The Kinematically Hot, Extremely Metal-Poor C-19 Stellar Stream in DESI DR2 Nasser Mohammed, Joseph Y. Tang, Ting S. Li, Sergey E. Koposov, Raymond G. Carlberg, Emma Jarvis, Andrew P. Li, Nathan Sandford, Gustavo E. Medina, Wenting Wang, Monica Valluri, Alexander H. Riley, Leandro Beraldo e Silva, Joan Najita, Mika Lambert, Songting Li, J. Aguilar, S. Ahlen, D. Bianchi, D. Brooks, T. Claybaugh, A. P. Cooper, A. de la Macorra, J. E. Forero-Romero, E. Gazta~naga, S. Gontcho A Gontcho, G. Gutierrez, R. Joyce, S. Juneau, R. Kehoe, T. Kisner, A. Kremin, M. Landriau, L. Le Guillou, M. Manera, A. Meisner, R. Miquel, S. Nadathur, W. J.Read More →

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In: arXiv

Spectral Decomposition Reveals Surface Processes on Europa Gideon Yoffe, Sahar Shahaf arXiv:2603.10520v2 Announce Type: replace Abstract: Competing processes shape Europa’s surface: geological activity replenishes material through resurfacing, while bombardment by charged particles alters surface chemical composition. Each process leaves distinct spectral signatures. We present a novel data-driven analysis of JWST NIRSpec-IFU observations of Europa’s leading hemisphere across three observing geometries, targeting nine spectral bands sensitive to water ice, radiolytic products, and volatiles. Through spectral factorization, we isolate the dominant components of spectral variability and reconstruct their spatial distributions. We find that CO2 enrichment extends beyond Tara Regio, and covers multiple chaos units in a lens-likeRead More →

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In: arXiv

Spontaneous Baryogenesis and Primordial Black Hole Dark Matter from Ultra-Slow-Roll Inflation Shyam Balaji arXiv:2603.11177v1 Announce Type: new Abstract: We propose a unified framework where the totality of dark matter (DM), the baryon asymmetry of the universe, and a detectable stochastic gravitational wave (GW) background originate from ultra-slow-roll (USR) inflation. The drastic suppression of the inflaton velocity during the USR phase, required for primordial black hole (PBH) DM production, can also set the initial conditions for spontaneous baryogenesis via a derivative coupling. This mechanism establishes a predictive correlation between the PBH abundance and the baryon yield, effectively fixing the reheating temperature $T_textrm{reh}$ as a function ofRead More →

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In: arXiv

Resonances in binary extreme mass ratio inspirals Jo~ao S. Santos, Vitor Cardoso, Alexandru Lupsasca, Jos’e Nat’ario, Maarten van de Meent arXiv:2601.02468v2 Announce Type: replace-cross Abstract: Stellar-mass binaries evolving in the vicinity of supermassive black holes (SMBHs) may be common in the universe, either in active galactic nuclei or in other astrophysical environments. Here, we study in detail the resonant excitation of SMBH modes driven by a nearby stellar-mass binary. The resulting resonant energy fluxes vary with the orbital location and frequency of the binary, exhibiting a rich and complex structure. In particular, we find that the total energy flux radiated to infinity is maximized atRead More →

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In: arXiv

A systematic study of AGN feedback in a disk galaxy I: global overview Yuxuan Zou, Feng Yuan, Suoqing Ji, Luis C. Ho, Yingjie Peng, Jing Wang, Bocheng Zhu, Tao Wang arXiv:2603.11179v1 Announce Type: new Abstract: This is the first paper in a series using our MACER framework to investigate the evolution of a disk galaxy, which emphasizes the role of active galactic nucleus (AGN) feedback and incorporates cosmological inflows. This paper presents the model setup and the overall results. The predicted AGN duty cycle of approximately 0.49% is consistent with observations. Analysis of the AGN luminosity and star formation rate (SFR) light curves reveals aRead More →