Hidden Charged Dark Matter

Abstract: Can dark matter be stabilized by charge conservation, just as the electron is in the standard model? We examine the possibility that dark matter is hidden, that is, neutral under all standard model gauge interactions, but charged under an exact U(1) gauge symmetry of the hidden sector. Such candidates are predicted in WIMPless models, supersymmetric models in which hidden dark matter has the desired thermal relic density for a wide range of masses. Hidden charged dark matter has many novel properties not shared by neutral dark matter: (1) bound state formation and Sommerfeld-enhanced annihilation after chemical freeze out may reduce its relic density, (2) similar effects greatly enhance dark matter annihilation in protohalos at redshifts of z ~ 30, (3) Compton scattering off hidden photons delays kinetic decoupling, suppressing small scale structure, and (4) Rutherford scattering makes such dark matter self-interacting and collisional, potentially impacting properties of the Bullet Cluster and the observed morphology of galactic halos. We analyze all of these effects in a WIMPless model in which the hidden sector is a simplified version of the minimal supersymmetric standard model and the dark matter is a hidden sector stau. We find that charged hidden dark matter is viable and consistent with the correct relic density for reasonable model parameters and dark matter masses in the range 1 GeV < m_X < 10 TeV. At the same time, in the preferred range of parameters, this model predicts cores in the dark matter halos of small galaxies and other halo properties that may be within the reach of future observations. These models therefore provide a viable and well-motivated framework for collisional dark matter with Sommerfeld enhancement, with novel implications for astrophysics and dark matter searches.

• The paper presents a hidden sector U(1) gauge model where dark matter carries a hidden charge while remaining neutral to Standard Model interactions.
• It shows that hidden charged dark matter can achieve consistent relic densities over a 1 GeV to 10 TeV mass range, with enhanced low-velocity annihilation via the Sommerfeld effect.
• The study highlights potential astrophysical signatures, including altered halo morphologies and the possibility of connector particles bridging hidden and observable sectors.

Analysis of Hidden Charged Dark Matter Models

The examined paper presents an intricate study analyzing the concept of hidden charged dark matter that interacts exclusively within a hidden sector U(1) gauge symmetry. The authors, Feng et al., explore the implications of dark matter candidates that are neutral with respect to all standard model (SM) gauge interactions but carry charge under an exact gauge symmetry that remains confined to the hidden sector. They explore numerous properties and dynamic behaviors arising from the distinctive characteristics of such hidden charged dark matter, notably within frameworks like WIMPless models and minimal supersymmetric standard models (MSSM).

The prominent highlight is the viability of hidden charged dark matter maintaining consistent relic density across a wide range of masses, approximately 1 GeV to 10 TeV, while concurrently remaining consistent with astrophysical observations and theoretical expectations. A salient feature explored is the Sommerfeld effect, which can significantly enhance annihilation cross-sections at low velocities—a potential mechanism impacting dark matter annihilation rates in protohalos and influencing the structuring of dark matter halos. Furthermore, the research investigates potential formation of bound states when dark matter particles are charged, exploring implications for kinetic decoupling, small-scale structure modulation, and the observable properties of galactic halos.

The analysis rigorously addresses potential impacts on the Bullet Cluster and otherwise observable elliptical galactic halos, noting that Charge conservation and long-range interactions inherent in their model may lead to collisional and self-interacting dark matter scenarios, influencing morphological characteristics of smaller galaxies’ dark matter halos. The outcomes suggest that while their model provides theoretical advantages akin to conventional WIMPs, their astrophysical signatures differ substantially, necessitating potential adjustments in the interpretation of direct and indirect dark matter search experiments.

Theoretical implications extend to revealing possibilities for multi-component dark matter dynamics, configurations where hidden charged dark matter could manifest alongside other hidden sector particles, offering a cohesive framework for tackling ongoing issues relating to dark matter’s role within smaller galactic scales and its interaction dynamics.

Feng et al. elevate the discourse by hypothesizing on the adaptability of their model to potential connector particles that may bridge hidden and observable sector communications, extending the significance to laboratory and collider explorations, showing remarkable adaptability of this conceptual framework for real-world applications. Innovative experimental setups might encounter new avenues for validation, bearing significance in the subtle corners of reduced mass-scan dark energy laboratory confines and the field of cosmological observations that could be realized in future space-based or remote ground facilities.

In conclusion, hidden charged dark matter provides a flexible and comprehensive paradigm that invites further inquiry into non-conventional dark matter models. This theoretical research yields a technically ambitious yet promising route toward resolving some of the enigmatic behaviors of dark matter, particularly when encountered on the relatively smaller galactic scale. Such exploration remains indispensable in understanding not only the cosmological narrative of dark matter evolution but also unlocking more profound theoretical relationships that could redefine dark matter interactions today and in prospective observation vistas.