Moderadores
Dark Matter: Indirect Detection: Indirect messengers
- Christopher Dessert (Flatiron Institute)
Dark Matter: Indirect Detection: Photons I
- Nirmal Raj (Indian Institute of Science)
Dark Matter: Indirect Detection: Stars and galaxies
- Matthew Baumgart ()
Dark Matter: Indirect Detection: Photons II
- Christopher Cappiello ()
This contribution presents the latest searches for dark matter with the KM3NeT neutrino telescope. Indirect searches for neutrinos from dark matter annihilations primarily probe weakly interacting massive particles (WIMPs). The largest flux is expected from WIMP annihilations in celestial objects with a large density of dark matter, such as the Galactic Centre and the Sun. In this work,...
Antimatter cosmic rays and gamma rays are powerful probes for indirect dark matter (DM) detection. In this talk, I will present the CosmiXs framework, which provides state-of-the-art predictions for the energy spectra of cosmic messengers—antiprotons, positrons, gamma rays, neutrinos, and antideuterons—produced from DM annihilation or decay. The spectra are calculated using the...
The study of cosmic rays with indirect detection searches provides a powerful tool to test the properties of dark matter (DM), especially through their potential imprints on the injection spectra. Adopting a model-independent approach, we systematically explore the characteristics of cosmic ray injection spectra arising from DM scenarios exhibiting a richer phenomenology. Our analysis goes...
The creation of anti-nuclei in the Galaxy has been discussed as a possible signal of exotic production mechanisms such as primordial black hole evaporation or dark matter decay/annihilation in addition to the more conventional production from cosmic-ray interactions. Tentative observations of cosmic-ray andideuteron and antihelium by the AMS-02 collaboration have re-energized the quest to use...
In this talk, we present a tuning of PYTHIA and a coalescence model that leads to realistic predictions of antinuclei production. This tuning is validated against LEP data including the fragmentation function of $b$-quarks into into $b$-hadrons, which is crucial for determining the $\bar{\Lambda}_b^0$ multiplicity. The coalescence model is tuned to ALICE data for the $\overline{\text{D}}$ and...
In this talk, we present our recent work on cosmic antimatter signatures from primordial black holes (PBHs). Light primordial black holes may have formed in the early Universe, and could contribute to the dark matter content of our Galaxy. Their Hawking evaporation into particles could lead to the production of antinuclei, which propagate and arrive at Earth as cosmic rays with a flux peaked...
Astrophysical jets from powerful active galactic nuclei (AGN) have recently been proposed as promising probes of dark matter (DM) in the sub-GeV mass range. These jets accelerate cosmic rays (CRs) to very high energies, which can then interact with their environments to produce multiwavelength (MW) emission ranging from radio frequencies to TeV $\gamma$ rays. If DM consists of light particles,...
The 3.5 keV line is a purported emission line observed in galaxies, galaxy clusters, and the Milky Way whose origin is inconsistent with known atomic transitions and has previously been suggested to arise from dark matter (DM) decay. I show why the line cannot arise from DM decay, and then describe work in which collaborators and I reanalyzed the datasets providing the bulk of the evidence for...
Fifteen years of the Fermi Large Area Telescope (LAT) data in the halo region of the Milky Way (MW) are analyzed to search for gamma rays from dark matter annihilation. Gamma-ray maps within the region of interest (|l| < 60 deg, 10 < |b| < 60 deg) are modeled using point sources, the GALPROP models of cosmic-ray interactions, isotropic background, and templates of Loop I and the Fermi bubbles,...
Weak-scale Dark Matter (DM) particles annihilating into lepton-rich channels in the Galaxy not only produce $\gamma$-rays via prompt radiation, but also generate abundant energetic $e^\pm$, which subsequently emit through inverse Compton scattering or bremsstrahlung (collectively called `secondary-radiation photons'). While the prompt $\gamma$-rays concentrate at high-energy, the secondary...
We present a novel algorithm for both forecasting and recasting upper limits (ULs) on dark matter (DM) annihilation cross sections. The forecasting method relies solely on the instrument response functions (IRFs) to predict ULs for a given observational setup. The recasting procedure uses published ULs to reinterpret results for alternative DM models or channels, without requiring access to...
We critically reassess the Minimal Dark Matter model and propose novel indirect detection signatures. Specifically, we compute the photon flux associated with the originally proposed accidentally stable SU(2) 5-plet, arising from Dark Matter bound state formation and Sommerfeld-enhanced annihilations. Our analysis reveals several distinctive spectral features that constitute promising targets...
Our understanding of the $\gamma$-ray sky has improved dramatically in the past decade, however, the unresolved $\gamma$-ray background (UGRB) still has a potential wealth of information about the faintest $\gamma$-ray sources pervading the Universe. Statistical cross-correlations with tracers of cosmic structure can indirectly identify the populations that most characterize the $\gamma$-ray...
The QCD axion, originally proposed to resolve the strong CP problem, is also a compelling dark matter (DM) candidate. In strong magnetic fields, such as those surrounding neutron stars, axions can convert into photons, potentially generating detectable radio signals. This axion-photon coupling offers a unique avenue for experimental searches in a well-defined mass range. In this seminar, I...
In this talk, we summarize our research on stellar streams as a new and complementary target for dark matter (DM) searches with gamma rays.
Stellar streams whose progenitor is a dwarf galaxy (dG) are particularly interesting targets for DM searches, since dGs are thought to be highly DM-dominated systems. We expect these streams to have lost most of their DM content during the stretching...
https://arxiv.org/abs/2506.01152
A number of studies assert that dark matter (DM) subhaloes without a baryonic counterpart and with an inner cusp always survive no matter the strength of the tidal force they undergo.
In this work, we perform a suite of numerical simulations specifically designed to analyse the evolution of the circular velocity peaks ($V_\mathrm{max}$, and its radial value...
The Dark Matter (DM) distribution within a few kpc of the center of galaxies is essential for indirect detection searches and probing the particle nature of DM. Below the kpc scale, we examine external galaxies where adiabatically growing black holes lead to the formation highly dense DM region dubbed the DM spike. These spikes may lie within galaxy radio jets, such as M87, where minimal...
A gamma-ray source has been identified at the center of the Sagittarius (Sgr) dwarf spheroidal. It is unclear whether the observed gamma-ray emission is from a millisecond pulsar population or from dark matter annihilation within the Sgr halo. Probing this ambiguity requires accurate knowledge of the Sgr dark matter distribution. However, since Sgr is in the process of tidal disruption, there...
Dark matter capture by celestial objects is widely studied as one of the methods to indirectly detect dark matter. Celestial objects, such as neutron stars, brown dwarfs, and planets, first gravitationally attract ambient dark matter particles. If dark matter particles are heavy enough, they transfer energy to those objects upon scattering, being gravitationally bound. This process ends up...
Jupiter has long been considered a pre-eminent target for dark matter searches, due to its proximity, mass, and low astrophysical backgrounds. However, low-mass dark matter ($\leq$400 MeV) is expected to efficiently evaporate from the Jovian core via interactions with standard model particles, limiting searches for dark matter effects. We show that in the case of leptophilic dark matter,...
The General Antiparticle Spectrometer (GAPS) is a balloon-borne cosmic-ray experiment designed to search for light antinuclei at kinetic energies below 0.25 GeV/n, a largely unexplored range that may carry distinctive signatures of dark matter.
The instrument consists of a ten-layer lithium-drifted silicon tracker, cooled by a novel oscillating heat pipe thermal system, and is enclosed on all...
While there exists overwhelming evidence pointing to the existence of dark matter (DM) as one of the components of the Universe, “what is the nature of DM?”, remains as one of the unsolved puzzles of modern physics. Several hypotheses and theories propose a new kind of particle to explain DM. Among them, candidates as Weekly Interactive Massive Particles (WIMPs), and ultra-light DM as...
Dwarf irregular galaxies (dIrrs) are rotationally supported galaxies, located in the Local Volume, and are considered to host star-forming regions with a low star-forming rate. Their gamma-ray background signal is expected to be low, making them interesting targets for WIMP Dark Matter (DM) indirect searches. Following previous works on dIrrs, we present the best four dIrrs targets for the...
The next decade will definitively test the “minimal” dark matter
paradigm. This is the attractive idea that extending the Standard
Model with a new electroweak multiplet allows for a simple resolution
of the Universe’s missing mass puzzle by a thermal relic particle.
We project CTAO limits for all real SU(2) multiplets consistent with
unitarity and find that with 500 hours of Galactic Center...
Axions and axion-like particles (ALPs) are hypothetical particles predicted by several extensions of the Standard Model and compelling dark matter candidates. Their conversion into photons in the presence of magnetic fields can leave distinctive imprints on the photon spectra of astrophysical sources. In gamma-ray astronomy, photon-ALP conversions may produce observable energy-dependent...
Under the hypothesis that thermal relic particles populate the dark matter halo of the Milky Way, strong indirect signals in cosmic radiation are expected from the regions where the dark matter density is high. In particular, the Galactic Center is potentially hosting the largest indirect signal from dark matter pair-annihilation (or decay), which in many theoretically well-motivated models...
Primordial Black Holes (PBHs) are hypothesized to have been formed in the Early Universe as a result of density fluctuations. In recent years, PBHs have gained attention, in part, for the possibility that they can account for a fraction or all the dark matter content of the Universe. PBHs formed with a mass around $10^{14}$g to $10^{15}$g should be evaporating in present times through the...
In this talk, I will present bounds on the variation of fundamental constants from the cosmic microwave background (CMB). In our theoretically motivated model, the variation is modulated by a scalar field that behaves as an ultralight dark matter (ULDM). We self-consistently compute the effects of the variation of constants on big bang nucleosynthesis (BBN) and propagate those effects to the...
