116 citations · 540 across the 21 of their papers we have counts for
21 papers
The COSMIC WISPers White Paper: The physics case for Weakly Interacting Slim Particles
Ariel Arza, Deniz Aybas, Shyam Balaji +124
Axions and other very weakly interacting slim particles (WISPs), with masses below 1 GeV, arise naturally in many extensions of the Standard Model of particle physics. In particula…
Probing Ultralight Dark Matter at the Mega-Planck Scale with the Thorium Nuclear Clock
Jason Arakawa, Jack F. Doyle, Elina Fuchs +10
Ultralight dark matter is expected to induce oscillations of nuclear parameters. These oscillations are characterized by extremely weak couplings or high suppression scales, with t…
Is the Conventional Picture of Coherence Time Complete? Dark Matter Recoherence
Chaitanya Paranjape, Gilad Perez, Wolfram Ratzinger +1
The local solar gravitational potential forms a basin for ultralight dark matter (ULDM), with discrete energy levels. Even if barely populated, it introduces a new characteristic t…
Search for a solar-bound axion halo using the Global Network of Optical Magnetometers for Exotic physics searches
Tatum Z. Wilson, Derek F. Jackson Kimball, Samer Afach +50
We report on a search for a gravitationally bound solar axion halo using data from the Global Network of Optical Magnetometers for Exotic physics searches (GNOME), a worldwide arra…
Search for high-frequency gravitational waves via re-analysis of cavity axion data
Younggeun Kim, Jordan Gué, Changhao Xu +17
Monochromatic high-frequency gravitational waves (HFGW) provide a distinctive probe of new physics scenarios, most notably axion clouds around rotating black holes formed via super…
Superhorizon Isocurvature as a Window into Dark Matter Production
Christopher Gerlach, Wolfram Ratzinger, Pedro Schwaller
In the presence of primordial isocurvature perturbations, for example in a separate dark radiation sector, the superhorizon evolution of curvature perturbations becomes nontrivial.…
Generalized neutrino isocurvature
Christopher Gerlach, Wolfram Ratzinger, Pedro Schwaller
Searches for neutrino isocurvature usually constrain a specific linear combination of isocurvature perturbations. In this work, we discuss realistic cosmological scenarios giving r…
Probing New Forces with Nuclear Clocks
Cédric Delaunay, Seung J. Lee, Roee Ozeri +3
Clocks based on nuclear isomer transitions promise exceptional stability and precision. The low transition energy of the thorium-229 isomer makes it an ideal candidate, as it has b…
Searching for dark matter with the Th-229 nuclear lineshape from laser spectroscopy
Elina Fuchs, Fiona Kirk, Eric Madge +5
The recent laser excitation of the low-lying Th-229 isomer transition is starting a revolution in ultralight dark matter searches. The enhanced sensitivity of this transition to th…
Nelson-Barr ultralight dark matter
Michael Dine, Gilad Perez, Wolfram Ratzinger +1
We show that, in the Nelson-Barr solution to the strong CP-problem, a naturally light scalar can arise. It gives rise to a completely new phenomenology beyond that of the celebrate…
A Coordinate-Independent Formalism for Detecting High-Frequency Gravitational Waves
Wolfram Ratzinger, Sebastian Schenk, Pedro Schwaller
In an external electric or magnetic field, a gravitational wave (GW) may be converted into electromagnetic radiation. We present a coordinate-invariant framework to describe the GW…
Probing an ultralight QCD axion with electromagnetic quadratic interaction
Hyungjin Kim, Alessandro Lenoci, Gilad Perez +1
The axion-gluon coupling is the defining feature of the QCD axion. This feature induces additional and qualitatively different interactions of the axion with standard model particl…
Primordial gravitational waves in the nano-Hertz regime and PTA data -- towards solving the GW inverse problem
Eric Madge, Enrico Morgante, Cristina Puchades-Ibáñez +4
In recent years, several pulsar timing array collaborations have reported first hints for a stochastic gravitational wave background at nano-Hertz frequencies. Here we elaborate on…
One to rule them all: CMB spectral distortions can probe domain walls, cosmic strings and low scale phase transitions
Nicklas Ramberg, Wolfram Ratzinger, Pedro Schwaller
We present a new probe of purely gravitationally coupled sectors with large anisotropies. These anisotropies are damped via gravitational interactions with the baryon-photon fluid,…
Audible Axions with a Booster: Stochastic Gravitational Waves from Rotating ALPs
Eric Madge, Wolfram Ratzinger, Daniel Schmitt +1
Gravitational waves provide a novel way to probe axions or axion-like particles coupled to a dark photon field, even in the absence of couplings to Standard Model particles. In the…
Axion Fragmentation on the Lattice
Enrico Morgante, Wolfram Ratzinger, Ryosuke Sato +1
We analyze the phenomenon of axion fragmentation when an axion field rolls over many oscillations of a periodic potential. This is particularly relevant for the case of relaxion, i…
Gravitational Wave Echo of Relaxion Trapping
Abhishek Banerjee, Eric Madge, Gilad Perez +2
To solve the hierarchy problem, the relaxion must remain trapped in the correct minimum, even if the electroweak symmetry is restored after reheating. In this scenario, the relaxio…
Gravitational Waves from an Axion-Dark Photon System: A Lattice Study
Wolfram Ratzinger, Pedro Schwaller, Ben A. Stefanek
In this work, we present a lattice study of an axion - dark photon system in the early Universe and show that the stochastic gravitational wave (GW) background produced by this sys…
Whispers from the dark side: Confronting light new physics with NANOGrav data
Wolfram Ratzinger, Pedro Schwaller
The NANOGrav collaboration has recently observed first evidence of a gravitational wave background (GWB) in pulsar timing data. Here we explore the possibility that this GWB is due…
Gravitational wave probes of axion-like particles
Camila S. Machado, Wolfram Ratzinger, Pedro Schwaller +1
We have recently shown that axions and axion-like particles (ALPs) may emit an observable stochastic gravitational wave (GW) background when they begin to oscillate in the early un…
Audible Axions
Camila S. Machado, Wolfram Ratzinger, Pedro Schwaller +1
Conventional approaches to probing axions and axion-like particles (ALPs) typically rely on a coupling to photons. However, if this coupling is extremely weak, ALPs become invisibl…