Tootfinder

Little Red Dots from Small-Scale Primordial Black Hole Clustering
Borui Zhang, Wei-Xiang Feng, Haipeng An
https://arxiv.org/abs/2507.07171 https://

Little Red Dots from Small-Scale Primordial Black Hole Clustering
The James Webb Space Telescope (JWST) observations have identified a class of compact galaxies at high redshifts ($4 \lesssim z \lesssim 11$), dubbed "little red dots" (LRDs). The supermassive black holes (SMBHs) of $10^{5-8}{\rm\,M}_{\odot}$ in LRDs favor a heavy-seed origin. We propose a mechanism for their formation: Clusters of primordial black holes, formed through long-short mode coupling on small scales in the early Universe, undergo sequential mergers over extended timescales. This mech…

A Common Origin of Asymmetric Self-interacting Dark Matter and Dirac Leptogenesis
Manoranjan Dutta, Nimmala Narendra
https://arxiv.org/abs/2506.22388 https…

A Common Origin of Asymmetric Self-interacting Dark Matter and Dirac Leptogenesis
Assuming dark matter to be asymmetric as well as self-interacting and neutrinos to be Dirac fermions, we propose a framework to address the observed baryon imbalance of the universe. We add three right-handed neutrinos $ν_{R_i},\,{i=1,2,3}$, one singlet fermion $χ$, a doublet fermion $ψ$, and heavy scalar doublets $η_i,\,{i=1,2}$ to the Standard Model. Both $χ$ and $ψ$ are fermions with non-zero charge under an extended $U(1)_{B-L} \times U(1)_D$ symmetry. Additionally, a $\mathcal{Z}_2$ …

Radio Galaxy Zoo: EMU -- paving the way for EMU cataloging using AI and citizen science
Hongming Tang, Eleni Vardoulaki, RGZ EMU collaboration
https://arxiv.org/abs/2506.16138

Radio Galaxy Zoo: EMU -- paving the way for EMU cataloging using AI and citizen science
The Evolutionary Map of the Universe (EMU) survey with ASKAP is transforming our understanding of radio galaxies, AGN duty cycles, and cosmic structure. EMUCAT efficiently identifies compact radio sources, yet struggles with extended objects, requiring alternative approaches. The Radio Galaxy Zoo: EMU (RGZ EMU) project proposes a general framework that combines citizen science and machine learning to identify around 4 million extended sources in EMU. This framework is expected to enhance the EM…

This https://arxiv.org/abs/2408.09964 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

Extended $δN$ formalism: Nonspatially Flat Separate Universe Approach
The $δN$ formalism is a powerful approach to compute non-linearly the large-scale evolution of the comoving curvature perturbation $ζ$. It assumes a set of FLRW patches that evolve independently, but in doing so, all the gradient terms are discarded, which are not negligibly small in models beyond slow-roll. In this Letter, we extend the formalism to capture these gradient corrections by encoding them in a homogeneous-spatial-curvature contribution assigned to each FLRW patch. For a concrete …

This https://arxiv.org/abs/2503.21368 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

The Jiutian simulations for the CSST extra-galactic surveys
We provide an overview of the Jiutian simulations, a hybrid simulation suite for the China Space Survey Telescope (CSST) extragalactic surveys. It consists of four complementary modules: the primary runs with high resolutions with the fiducial concordance cosmology, the emulator runs exploring the parameter uncertainties around the fiducial cosmology, the reconstruction runs intended for recovering the observed Universe position by position, and the extension runs employing extended cosmologies…

WIMP/FIMP dark matter and primordial black holes with memory burden effect
Amane Takeshita, Teruyuki Kitabayashi
https://arxiv.org/abs/2506.20071 https://

WIMP/FIMP dark matter and primordial black holes with memory burden effect
The lifetime of primordial black holes (PBHs), which were formed in the early universe, can be extended by the memory burden effect. Light PBHs may be in existence today and become a candidate for dark matter (DM). We assume that DM is made of thermally produced weakly interacting massive particles (WIMPs), WIMPs produced via Hawking radiation of PBHs, and survived PBHs via the memory burden effect. In addition, feebly interacting massive particles (FIMPs) are considered as an alternative to WI…

Extended datasamples under the lens of Brane World Theory
Kyra Jacobo, Dorian Araya
https://arxiv.org/abs/2506.15002 https://arxiv.or…

Extended datasamples under the lens of Brane World Theory
This work revises the Brane World Theory known as Randall-Sundrum with the modification of an exponential, redshift-dependent brane tension. This model is studied in a scenario assuming no dark energy, with the aim of determining whether it can reproduce the universe's acceleration on its own, without the addition of a dark energy fluid. Bayesian statistical analysis is performed in order to constrain the free parameters of each scenario using SLS, SNIa, OHD, and BAO data samples, the last two …