Article
Astronomy & Astrophysics
Sandeep Kumar Acharya, Jens Chluba
Summary: The observed excess radio background has puzzled scientists for over a decade. A recent new physics solution involves the decay of dark matter into dark photons which then convert into standard photons in the reionization era. This simple power-law model fits the current data closely, although additional work is needed to address challenges and improve the model.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Eleonora Di Valentino, Nils A. Nilsson, Mu-In Park
Summary: This study proposes a renormalizable, higher derivative, Lorentz-violating quantum gravity model without ghost problems known as Hoava gravity. Furthermore, a Hoava gravity-based dark energy (HDE) model is proposed by identifying the additional contributions from Lorentz-violating terms as an effective energy-momentum tensor in Einstein equation. The results show a preference for non-flat universes in the cosmic microwave background, baryon acoustic oscillation, and supernova Ia data tests, aligning with the cosmic concordance model.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Sandeep Kumar Acharya, Jiten Dhandha, Jens Chluba
Summary: The excess radio background observed at similar to 0.1-10GHz has sparked scientific debate in recent years. A recent hypothesis suggests that the soft photon emission from accreting primordial black holes could explain this signal. However, our study shows that the expected ultraviolet photon emission from these accreting black holes would fully ionize the universe at z > 6, thereby diminishing the 21-cm absorption signature at z similar to 20 and conflicting with the current limits of cosmic microwave background anisotropy and average spectral distortion.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Sandeep Kumar Acharya, Jens Chluba
Summary: The Sunyaev-Zeldovich effect is a widely used probe for studying cosmology through the scattering of photons from the cosmic microwave background by hot cluster electron gas. This study investigates the scattering of other photon backgrounds, specifically the cosmic infrared background (CIB), in cluster medium. The analysis reveals an underestimation of the all-sky CIB distortion due to neglecting the intracluster scattering contribution, and suggests a redshift dependence in the single-cluster CIB scattering signal, which can be utilized in future cosmological studies with CMB experiments.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Eleonora Di Valentino, Alessandro Melchiorri, Olga Mena, Supriya Pan, Weiqiang Yang
Summary: Recent measurements by the Planck satellite suggest a preference for a closed universe, but this conflicts with low redshift observables such as Type Ia supernovae luminosity distances. Interacting dark energy models could help reconcile these discrepancies in a closed Universe, indicating potential for a different coupling and curvature above 99% confidence level. This highlights the significance of broader cosmological data analyses and the possibility of better agreement between theory and observations by relaxing flatness and vacuum energy assumptions.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Weiqiang Yang, Eleonora Di Valentino, Supriya Pan, Yabo Wu, Jianbo Lu
Summary: This article compares various dynamical dark energy models using different observational data and discusses the alleviation of H-0 tension. Bayesian evidence analysis shows that all models perform better than Lambda CDM scenario, with the CPL model being the best in fitting the data and solving H-0 tension. However, the tension reappears when considering the baryon acoustic oscillations data, not supporting the dynamical dark energy solution.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Shikhar Mittal, Girish Kulkarni
Summary: In this study, we computed the isotropic radiation background from Hawking emission of primordial black holes (PBHs) and found that even under the extreme assumption that all dark matter is in the form of PBHs, the resulting radio brightness temperature is highly subdominant compared to the observed excess radio background. We also considered the alternative possibility of radio emission from gas accretion onto supermassive PBHs.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
M-A Sanchis-Lozano, F. Melia, M. Lopez-Corredoira, N. Sanchis-Gual
Summary: Recent research has found that there is a maximum correlation angle in the two-point angular temperature correlations of cosmic microwave background (CMB) radiation, which contradicts the prediction of standard cosmology. The angular power spectrum of the CMB also shows a dominance of odd-over-even parity multipoles. This paper examines the relationship between these features and their impact on the theoretical fit to the Planck 2018 data. The results suggest that considering both the maximum correlation angle and the parity imbalance is crucial for optimizing the fit.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Eleonora Di Valentino
Summary: The study combines multiple measurements of the Hubble constant, resulting in an optimistic estimate of H-0 = 72.94 +/- 0.75 km s(-1) Mpc(-1), significantly different from the ACDM model. The research also highlights various new phenomena that emerge in different dark energy cosmological models, such as phantom dark energy and coupling between dark matter and dark energy.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Sergei F. Shandarin
Summary: The study examines the density distribution of dark matter at caustic surfaces and the corresponding geometrical features, as well as the methods and challenges in identifying caustics in numerical simulations. The halo boundary is found to be asymmetrical, but a convex hull is a good approximation. Analyses of kinetic and potential energies, as well as examination of the two-dimensional phase space, confirm that the halo is gravitationally bound. The discovery of non-ellipsoidal oval shapes in a sample of halos from large simulations shows promise for further detailed analysis on higher resolution simulations.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
L. Gelo, C. J. A. P. Martins, N. Quevedo, A. M. M. Vieira
Summary: The redshift dependence of the cosmic microwave background temperature has important implications for fundamental cosmology, and its constraining power is comparable to other background cosmology probes.
Article
Astronomy & Astrophysics
Nanoom Lee, Yacine Ali-Haimoud
Summary: This study introduces a new formalism to compute the impact of small-scale baryon perturbations on free-electron abundance and applies it to probe cosmic microwave background anisotropies. Analysis on four different combinations of fluctuation modes shows that Planck data is consistent with the absence of small-scale isocurvature perturbations.
Article
Astronomy & Astrophysics
E. Camphuis, K. Benabed, S. Galli, E. Hivon, M. Lilley
Summary: This study focuses on the analytical calculation of covariance matrices for estimating cosmological parameters, particularly in the observation of CMB using small footprints. A new approximation method is introduced to improve the accuracy in predicting wide bandpowers, achieving over four times the precision compared to current approaches. The results are not only applicable to CMB observations but also to other cosmological probes requiring the calculation of pseudo-power spectrum covariance matrices.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Abineet Parichha, Shiv Sethi
Summary: This study proposes a decaying WIMP model that can address the issues with the CDM model at small scales. By comparing the predictions of this model with CMB and galaxy clustering data, the effectiveness of the model is demonstrated and constraints on certain parameters are obtained.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Wonsub Cho, Ki-Young Choi, Hee Jung Kim
Summary: We studied the impact of the interaction between dark matter and the cosmic neutrino background on the evolution of galactic dark matter halos. We found that energy transfer from the cosmic background neutrinos can heat the center of the galaxy and lead to core formation. For small galaxies, such as satellite galaxies of the Milky Way, core formation is particularly efficient. We were able to put a conservative constraint on the non-relativistic elastic scattering cross section.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Hendrik Muller, Christoph Behrens, David J. E. Marsh
Summary: The method proposed in this study combines Lyα forest tomography with different inversion algorithms to estimate the equation of state of the intergalactic medium in the quasi-linear regime of structure formation. By analyzing 21 high-quality quasar spectra, the estimation is more precise than existing estimates, particularly on small redshift bins. The study also provides measurements for temperature-density relation and photoionization rate.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Viraf M. Mehta, Mehmet Demirtas, Cody Long, David J. E. Marsh, Liam McAllister, Matthew J. Stott
Summary: In this study, an extensive analysis of axion masses and interactions in compactifications of type IIB string theory was performed, revealing that black hole superradiance excludes certain regions of Calabi-Yau moduli space. The study shows that the properties of astrophysical black holes can probe theories with axion masses falling in a superradiant band, unless disrupted by large axion self-interactions. The mass spectrum of axions is largely determined by the Kahler parameters, with constraints on superradiance conditions varying depending on the value of h(1,1).
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Jan Schuette-Engel, David J. E. Marsh, Alexander J. Millar, Akihiko Sekine, Francesca Chadha-Day, Sebastian Hoof, Mazhar N. Ali, Kin Chung Fong, Edward Hardy, Libor Smejkal
Summary: It has been proposed that certain antiferromagnetic topological insulators may contain axion quasiparticles which can be used to detect axion dark matter. By calculating electromagnetic boundary conditions, transmission and reflection coefficients, a model is presented to measure resonant frequencies and damping coefficients of the material, confirming the existence of axion quasiparticles. The research shows that transmission spectroscopy can be used to achieve resonant conversion of axion dark matter into THz photons in a material volume independent of the resonant frequency.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
A. Lague, J. R. Bond, R. Hlozek, K. K. Rogers, D. J. E. Marsh, D. Grin
Summary: This study tests the effective field theory approach to mixed ultralight axion dark matter using mock galaxy catalogs and detects an anisotropic signature of ultralight axions in the galaxy quadrupole. The upper bounds for axion relic density are obtained based on galaxy clustering statistics from the Baryon Oscillation Spectroscopic Survey, with improved constraints compared to using only cosmic microwave background data. The computational cost is reduced by 70% through the development of an augmented interpolation scheme.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Review
Multidisciplinary Sciences
Francesca Chadha-Day, John Ellis, David J. E. Marsh
Summary: This article reviews the development of the axion as a candidate particle for dark matter. It describes the historical roots of the axion in the Standard Model of particle physics and the problem of charge-parity invariance of the strong nuclear force. It discusses the production of the axion as a dark matter candidate and its interactions with ordinary matter.
Article
Astronomy & Astrophysics
Moslem Zarei, Soroush Shakeri, Mohammad Sharifian, Mehdi Abdi, David J. E. Marsh, Sabino Matarrese
Summary: A detection scheme for Axion-Like Particles (ALPs) based on axion-photon interaction in a non-uniform magnetic field is proposed. The experiment allows exclusion of a range of axion masses not covered by other techniques.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Mona Dentler, David J. E. Marsh, Renee Hlozek, Alex Lague, Keir K. Rogers, Daniel Grin
Summary: Gravitational weak lensing by dark matter haloes leaves a measurable imprint in galaxy shear correlation function. Fuzzy dark matter (FDM), composed of ultralight axion-like particles, suppresses matter power spectrum and shear correlation. Our analysis sets a new lower limit to FDM particle mass, improving the mass bound by almost two orders of magnitude compared to previous constraints.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Physics, Multidisciplinary
David J. E. Marsh
Summary: This paper discusses how time series obtained from searches for ultralight bosonic dark matter can be used to determine the quantum state of the dark matter. While the example is trivial, it is hoped to encourage experimental exploration.
ANNALEN DER PHYSIK
(2023)
Article
Astronomy & Astrophysics
Liina M. Chung-Jukko, Eugene A. Lim, David J. E. Marsh, Josu C. Aurrekoetxea, Eloy de Jong, Bo-Xuan Ge
Summary: This study demonstrates the instability of compact axion stars due to the electromagnetic Chern-Simons term through fully nonlinear numerical relativity. The research shows that compact axion stars are only stable when the coupling constant is below the critical value.
Article
Astronomy & Astrophysics
David Ellis, David J. E. Marsh, Benedikt Eggemeier, Jens Niemeyer, Javier Redondo, Klaus Dolag
Summary: The peak-patch algorithm is used to identify the densest minicluster seeds in the initial axion density field. Tracking the subsequent gravitational collapse, it is found that the late-time miniclusters can be described by Navarro-Frenk-White profiles or a power-law density profile. Assuming that all miniclusters with an unresolved scale radius follow a power-law plus axion star density profile, a significant number of miniclusters dense enough for gravitational microlensing are identified. Higher resolution simulations are needed to explore the inner structure and axion star formation further.
Article
Astronomy & Astrophysics
Jiajun Chen, Xiaolong Du, Erik W. Lentz, David J. E. Marsh
Summary: In this paper, we investigate the Bose-Einstein condensation of a scalar field with an attractive self-interaction, with or without gravitational interactions. Our full dynamical simulation confirms that the condensation timescale due to self-interaction is inversely proportional to the square of the number density n and the self-coupling constant g: τ ∝ n(-2)g(-2). Additionally, we analyze the condensation timescale when both self-interaction and gravity are important and find that the condensation time scales according to an additive model for the cross section. We discuss the relevance of our findings to theoretical models of boson star formation by condensation.
Article
Astronomy & Astrophysics
Gerrit S. Farren, Daniel Grin, Andrew H. Jaffe, Renee Hlozek, David J. E. Marsh
Summary: This paper investigates the impact of ultralight axion dark matter on the kinetic Sunyaev-Zel'dovich (kSZ) effect and provides new analytic expressions for calculating the observables. The results indicate that future CMB measurements have the potential to detect the presence of axion dark matter and estimate its mass range.
Article
Astronomy & Astrophysics
Jiajun Chen, Xiaolong Du, Erik W. Lentz, David J. E. Marsh, Jens C. Niemeyer
Summary: This study investigates the formation and growth of boson stars and their surrounding miniclusters through gravitational condensation using nonlinear dynamical numerical methods, considering attractive and repulsive self-interactions. Strong attractive self-interactions can cause instability and collapse of boson stars, while repulsive self-interactions promote their formation and result in solutions with larger radii.
Article
Physics, Particles & Fields
Peter Athron, Csaba Balazs, Ankit Beniwal, J. Eliel Camargo-Molina, Andrew Fowlie, Tomas E. Gonzalo, Sebastian Hoof, Felix Kahlhoefer, David J. E. Marsh, Markus Tobias Prim, Andre Scaffidi, Pat Scott, Wei Su, Martin White, Lei Wu, Yang Zhang
Summary: The excess of electron recoil events observed in the XENON1T experiment has been proposed to potentially indicate axion-like particles (ALPs) originated from the Sun or dark matter halo, or due to trace amounts of tritium in the experiment. Combining XENON1T data with astrophysical probes supports the dark matter ALP hypothesis, despite the need for tuning unknown parameters. Bayesian analysis does not show strong preference for the ALP interpretation of the XENON1T excess over the background hypothesis, despite the tensions in the case of solar ALPs.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Astronomy & Astrophysics
David Ellis, David J. E. Marsh, Christoph Behrens
Summary: The study presents a modified peak patch excursion set formalism for computing the mass and size distribution of QCD axion miniclusters, based on a fully non-Gaussian initial density field obtained from numerical simulations of axion string decay. Strong agreement with N-body simulations is found at significantly lower computational cost. The method employs a spherical collapse model and provides fitting functions for the modified barrier in the radiation era.