Physics of the Dark Universe

Journal: Physics of the Dark Universe

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Elsevier

ISSN

2212-6864

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Publications 1 - 10 of 13

A search for dark matter in Triangulum II with the MAGIC telescopes
MAGIC Collaboration; Acciari, Victor A.; Arbet Engels, Axel; et al. (2020)
Physics of the Dark Universe
Constraints on axion-like particles with the Perseus Galaxy Cluster with MAGIC
Abe, Hyuga; Abe, S.; Abhir, Jayant; et al. (2024)
Physics of the Dark Universe
Searching for galactic axions through magnetized media: The QUAX proposal
Barbieri, Riccardo; Braggio, Caterina; Carugno, Giovanni; et al. (2017)
Physics of the Dark Universe
The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
The CosmoVerse Network; Di Valentino, Eleonora; Levi Said, Jackson; et al. (2025)
Physics of the Dark Universe
The standard model of cosmology has provided a good phenomenological description of a wide range of observations both at astrophysical and cosmological scales for several decades. This concordance model is constructed by a universal cosmological constant and supported by a matter sector described by the standard model of particle physics and a cold dark matter contribution, as well as very early-time inflationary physics, and underpinned by gravitation through general relativity. There have always been open questions about the soundness of the foundations of the standard model. However, recent years have shown that there may also be questions from the observational sector with the emergence of differences between certain cosmological probes. In this White Paper, we identify the key objectives that need to be addressed over the coming decade together with the core science projects that aim to meet these challenges. These discordances primarily rest on the divergence in the measurement of core cosmological parameters with varying levels of statistical confidence. These possible statistical tensions may be partially accounted for by systematics in various measurements or cosmological probes but there is also a growing indication of potential new physics beyond the standard model. After reviewing the principal probes used in the measurement of cosmological parameters, as well as potential systematics, we discuss the most promising array of potential new physics that may be observable in upcoming surveys. We also discuss the growing set of novel data analysis approaches that go beyond traditional methods to test physical models. These new methods will become increasingly important in the coming years as the volume of survey data continues to increase, and as the degeneracy between predictions of different physical models grows. There are several perspectives on the divergences between the values of cosmological parameters, such as the model-independent probes in the late Universe and model-dependent measurements in the early Universe, which we cover at length. The White Paper closes with a number of recommendations for the community to focus on for the upcoming decade of observational cosmology, statistical data analysis, and fundamental physics developments.
Combined searches for dark matter in dwarf spheroidal galaxies observed with the MAGIC telescopes, including new data from Coma Berenices and Draco
The MAGIC Collaboration; Acciari, Victor A.; Ansoldi, Stefano; et al. (2022)
Physics of the Dark Universe
Milky Way dwarf spheroidal galaxies (dSphs) are among the best candidates to search for signals of dark matter annihilation with Imaging Atmospheric Cherenkov Telescopes, given their high mass-to-light ratios and the fact that they are free of astrophysical gamma-ray emitting sources. Since 2011, MAGIC has performed a multi-year observation program in search for Weakly Interacting Massive Particles (WIMPs) in dSphs. Results on the observations of Segue 1 and Ursa Major II dSphs have already been published and include some of the most stringent upper limits (ULs) on the velocity-averaged cross-section 〈σannv〉 of WIMP annihilation from observations of dSphs. In this work, we report on the analyses of 52.1h of data of Draco dSph and 49.5h of Coma Berenices dSph observed with the MAGIC telescopes in 2018 and in 2019 respectively. No hint of a signal has been detected from either of these targets and new constraints on the 〈σannv〉 of WIMP candidates have been derived. In order to improve the sensitivity of the search and reduce the effect of the systematic uncertainties due to the J-factor estimates, we have combined the data of all dSphs observed with the MAGIC telescopes. Using 354.3h of dSphs good quality data, 95% CL ULs on 〈σannv〉 have been obtained for 9 annihilation channels. For most of the channels, these results reach values of the order of 10−24cm3/s at ∼1TeV and are the most stringent limits obtained with the MAGIC telescopes so far.
Beyond ΛCDM: Problems, solutions, and the road ahead
Bull, Philip; Akrami, Yashar; Adamek, Julian; et al. (2016)
Physics of the Dark Universe
lenstronomy: Multi-purpose gravitational lens modelling software package
Birrer, Simon; Amara, Adam (2018)
Physics of the Dark Universe
Synergy between cosmological and laboratory searches in neutrino physics
Gerbino, Martina; Grohs, Evan; Lattanzim, Massimiliano; et al. (2023)
Physics of the Dark Universe
The intersection of the cosmic and neutrino frontiers is a rich field where much discovery space still remains. Neutrinos play a pivotal role in the hot big bang cosmology, influencing the dynamics of the universe over numerous decades in cosmological history. Recent studies have made tremendous progress in understanding some properties of cosmological neutrinos, primarily their energy density. Upcoming cosmological probes will measure the energy density of relativistic particles with higher precision, but could also start probing other properties of the neutrino spectra. When convolved with results from terrestrial experiments, cosmology can become even more acute at probing new physics related to neutrinos or even Beyond the Standard Model (BSM). Any discordance between laboratory and cosmological data sets may reveal new BSM physics and/or suggest alternative models of cosmology. We give examples of the intersection between terrestrial and cosmological probes in the neutrino sector, and briefly discuss the possibilities of what different laboratory experiments may see in conjunction with cosmological observatories.
A way forward for Cosmic Shear: Monte-Carlo Control Loops
Refregier, Alexandre; Amara, Adam (2014)
Physics of the Dark Universe
Weak lensing by large scale structure or ‘cosmic shear’ is a potentially powerful cosmological probe to shed new light on Dark Matter, Dark Energy and Modified Gravity. It is based on the weak distortions induced by large-scale structures on the observed shapes of distant galaxies through gravitational lensing. While the potentials of this purely gravitational effect are great, results from this technique have been hampered because the measurement of this weak effect is difficult and limited by systematics effects. In particular, a demanding step is the measurement of the weak lensing shear from wide field CCD images of galaxies. We describe the origin of the problem and propose a way forward for cosmic shear. Our proposed approach is based on Monte-Carlo Control Loops and draws upon methods widely used in particle physics and engineering. We describe the control loop scheme and show how it provides a calibration method based on fast image simulations tuned to reproduce the statistical properties of a specific cosmic shear data set. Through a series of iterative loops and diagnostic tests, the Monte Carlo image simulations are made robust to perturbations on modeling input parameters and thus to systematic effects. We discuss how this approach can make the problem tractable and unleash to full potential of cosmic shear for cosmology.
Simultaneously solving the H0 and σ8 tensions with late dark energy
Heisenberg, Lavinia; Villarrubia-Rojo, Hector; Zosso, Jann (2023)
Physics of the Dark Universe
In a model independent approach, we derive generic conditions that any late time modification of the ΛCDM expansion history must satisfy in order to consistently solve both the H0 and the σ8 tensions. Our results are fully analytical and the method is merely based on the assumption that the late-time deviations from ΛCDM remain small. For the concrete case of a dark energy fluid with deviations encoded in the expansion history and the gravitational coupling constant, we present necessary conditions on its equation of state. Solving both the H0 and σ8 tensions requires that w(z) must cross the phantom divide if Geff=G. On the other hand, for Geff=G+δG(z) and w(z)≤−1, it is required that [Formula presented] at some redshift z.

Publications 1 - 10 of 13

Journal: Physics of the Dark Universe

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