18 citations · 72 across the 14 of their papers we have counts for
16 papers
Mineral Detection of Neutrinos and Dark Matter 2026 Proceedings
Alexey Elykov, Patrick Stengel, Natsue Abe +81
The fourth "Mineral Detection of Neutrinos and Dark Matter" (MDvDM'26) meeting was held April 14-17, 2026 in Karlsruhe, Germany, hosted by the Institute for Astroparticle Physics (…
Macroscopic dark matter constraints for extended mass functions
Zachary S. C. Picker, Andrew Buchanan, Melissa Diamond +1
We compile and recompute a subset of the landscape of constraints for macroscopic dark matter (macros), explicitly including the dependence on the fraction of dark matter in macros…
When Tiny Halos Stir Spacetime: Gravitational Waves from Fifth-Force Mergers
Xinpeng Wang, Yifan Lu, Zachary S. C. Picker +2
Dark matter fermions interacting via attractive fifth forces mediated by a light mediator can form dark matter halos in the very early universe. We show that bound systems composed…
Neutrino masses, matter-antimatter asymmetry, dark matter, and supermassive black hole formation explained with Majorons
Yifan Lu, Zachary S. C. Picker, Alexander Kusenko +1
The spontaneous breaking of a global lepton number symmetry can result in a (pseudo) Nambu-Goldstone boson known as the Majoron. We study a singlet Majoron model that couples to tw…
A dark matter hail: Detecting macroscopic dark matter with asteroids, planetary rings, and craters
Zachary S. C. Picker
Dark matter could be composed of macroscopic objects with large masses and geometric cross-sections spanning many decades. We investigate the potential interaction of such `stuff-s…
Black Holes from Fermi Ball Collapse
Yifan Lu, Zachary S. C. Picker, Stefano Profumo +1
Fermi balls are non-topological solitons that can naturally form in an early universe containing a dark sector with heavy fermions and an attractive interaction mediated by a light…
Direct-collapse supermassive black holes from relic particle decay
Yifan Lu, Zachary S. C. Picker, Alexander Kusenko
We investigate the formation of high-redshift supermassive black holes (SMBHs) via the direct collapse of baryonic clouds, where the unwanted formation of molecular hydrogen is suc…
Feeding plankton to whales: high-redshift supermassive black holes from tiny black hole explosions
Yifan Lu, Zachary S. C. Picker, Alexander Kusenko
Recent observations of the high-redshift universe have uncovered a significant number of active galactic nuclei, implying that supermassive black holes (SMBHs) would have to have b…
Explaining the GeV excess with exploding black holes
Zachary S. C. Picker, Alexander Kusenko
Black holes may form in present-day collapse of microscopic structures of dark matter. We show that, if microstructure black holes (MSBH) with mass are produced,…
Constraints on late-forming exploding black holes
Zachary S. C. Picker, Alexander Kusenko
Black holes can be produced in collapse of small-scale dark matter structures, which can happen at any time from the early to present-day universe. Microstructure black holes (MSBH…
Effects of Hawking evaporation on PBH distributions
Markus R. Mosbech, Zachary S. C. Picker
Primordial black holes (PBHs) may lose mass by Hawking evaporation. For sufficiently small PBHs, they may lose a large portion of their formation mass by today, or evaporate comple…
Apparent horizons of the Thakurta spacetime and the description of cosmological black holes
Archil Kobakhidze, Zachary S. C. Picker
We discuss the validity of the Thakurta metric to describe cosmological black holes by analysing the nature of its horizon. By adopting the preferred foliation of the Thakurta spac…
Cosmology of the companion-axion model: dark matter, gravitational waves, and primordial black holes
Zhe Chen, Archil Kobakhidze, Ciaran A. J. O'Hare +2
The companion-axion model introduces a second QCD axion to rescue the Peccei-Quinn solution to the strong-CP problem from the effects of colored gravitational instantons. As in sin…
Phenomenology of the companion-axion model: photon couplings
Zhe Chen, Archil Kobakhidze, Ciaran A. J. O'Hare +2
We study the phenomenology of the 'companion-axion model' consisting of two coupled QCD axions. The second axion is required to rescue the Peccei-Quinn solution to the strong-CP pr…
Comment on: Cosmological black holes are not described by the Thakurta metric
Celine Boehm, Archil Kobakhidze, Ciaran A. J. O'Hare +2
Recently, Hütsi et al.[arXiv:2105.09328] critiqued our work that reconsidered the mathematical description of cosmological black holes. In this short comment, we highlight some of…
Probing Quadratic Gravity with Binary Inspirals
Yunho Kim, Archil Kobakhidze, Zachary S. C. Picker
In this paper, we study gravitational waves generated by binary systems within an extension of General Relativity which is described by the addition of quadratic in curvature tenso…