532 citations · 1.7k across the 53 of their papers we have counts for
45 papers · 1 filter
Perturbative QCD correction to the nonleptonic weak rate in dense quark matter
Matti Heikinheimo, Hanna Lempiäinen, Risto Paatelainen +2
We present the first calculation of the leading perturbative quantum chromodynamics (QCD) correction to the nonleptonic weak flavor-equilibration rate in dense quark matter. The co…
Cosmic ray boosted dark matter with momentum dependent interactions can explain the LZ 248 keV event
Matti Heikinheimo, Niklas Zimmermann
The LZ experiment has recently reported an observation of a single event with characteristics of a nuclear recoil at a high recoil energy of 248 keV, where no background events are…
Anisotropic electron scattering and Migdal effect in semiconductor detectors
Aula Al-Adulrazzaq, Paolo Settembri, Sebastian Sassi +4
Cryogenic semiconductor detectors are widely used in dark matter direct detection. Electronic excitations in these materials can be caused either by direct dark matter electron sca…
Landau-Zener formula and resonant axion conversion in neutron star magnetospheres
Matti Heikinheimo, Topi Sirkiä, Kimmo Tuominen
We investigate the Landau-Zener description of resonant axion-photon conversion in neutron star magnetospheres. We find that this picture often fails for axion conversions to milli…
Fast numerical evaluation of dark matter direct detection event rates
Sebastian Sassi, Aula Al-Adulrazzaq, Matti Heikinheimo +1
The mathematical expression for the dark matter nuclear recoil event rate in a detector consists of a six dimensional integral over the velocity distribution of dark matter in the…
Axion Superradiance in Dipole Magnetic Fields of Pulsars
Topi Sirkiä, Matti Heikinheimo, Kimmo Tuominen
We consider constraints on the axion-photon coupling by superradiance due to a plasma instability in the magnetospheres of millisecond pulsars. We compute the growth rate of a supe…
Probing the dark matter velocity distribution via daily modulation
Matti Heikinheimo, Kai Nordlund, Sebastian Sassi +1
We consider dark matter velocity distributions with an anisotropic component, and analyze how the velocity structure can be probed in a solid state ionization detector with no dire…
Anatomy of real intermediate state-subtraction scheme
Kalle Ala-Mattinen, Matti Heikinheimo, Kimmo Kainulainen +1
We study the origin of the real intermediate state subtraction problem and compare its different solutions. We show that the ambiguity in subtraction schemes arises from the on-she…
Gravitational waves from composite Higgs models
Mads T. Frandsen, Matti Heikinheimo, Martin Rosenlyst +2
We study possible strong first-order electroweak phase transitions in Composite Higgs models and we quantify the part of parameter space that can be probed with future gravitationa…
Daily and annual modulation rate of low mass dark matter in silicon detectors
Abolfazl Dinmohammadi, Matti Heikinheimo, Nader Mirabolfathi +4
Low threshold detectors with single-electron excitation sensitivity to nuclear recoil events in solid-state detectors are also sensitive to the crystalline structure of the target…
Vector dark matter in supercooled Higgs portal models
Mads T. Frandsen, Matti Heikinheimo, Mattias E. Thing +2
We consider extensions of the Standard Model by a hidden sector consisting of a gauge field coupled with a scalar field. Assuming the absence of dimensionful parameters in the tree…
Anisotropic ionization threshold and directional sensitivity in solid state DM detectors
Matti Heikinheimo, Sebastian Sassi, Kimmo Tuominen +2
The threshold displacement energy for nuclear recoils depends strongly on the direction of the recoiling nucleus with respect to the crystal lattice. Assuming that similar dependen…
Energy loss in low energy nuclear recoils in dark matter detector materials
Sebastian Sassi, Matti Heikinheimo, Kimmo Tuominen +4
Recent progress in phonon-mediated detectors with eV-scale nuclear recoil energy sensitivity requires an understanding of the effect of the crystalline defects on the energy spectr…
Momentum distributions of cosmic relics: Improved analysis
Kalle Ala-Mattinen, Matti Heikinheimo, Kimmo Kainulainen +1
We solve coupled momentum-dependent Boltzmann equations for the phase space distribution of cosmic relic particles, without resorting to approximations of assuming kinetic equilibr…
Identification of the low energy excess in dark matter searches with crystal defects
Matti Heikinheimo, Sebastian Sassi, Kai Nordlund +2
An excess of events of unknown origin at low energies below 1 keV has been observed in multiple low-threshold dark matter detectors. Depending on the target material, nuclear recoi…
Solar neutrinos and dark matter detection with diurnal modulation
Sebastian Sassi, Abolfazl Dinmohammadi, Matti Heikinheimo +4
We investigate the diurnal modulation of the event rate for dark matter scattering on solid targets arising from the directionally dependent defect creation threshold energy. In pa…
Pseudo-Goldstone dark matter: gravitational waves and direct-detection blind spots
Tommi Alanne, Nico Benincasa, Matti Heikinheimo +4
Pseudo-Goldstone dark matter is a thermal relic with momentum-suppressed direct-detection cross section. We study the most general model of pseudo-Goldstone dark matter arising fro…
Velocity Dependent Dark Matter Interactions in Single-Electron Resolution Semiconductor Detectors with Directional Sensitivity
Matti Heikinheimo, Kai Nordlund, Kimmo Tuominen +1
We investigate the velocity and recoil momentum dependence of dark matter interactions with ordinary matter. In particular we focus on the single-electron resolution semiconductor…
Direct and indirect probes of Goldstone dark matter
Tommi Alanne, Matti Heikinheimo, Venus Keus +2
There exists a general model framework where dark matter can be a vanilla WIMP-like thermal relic with a mass of (100 GeV), but it still escapes direct detection. This ha…
Cosmological constraints on light flavons
Matti Heikinheimo, Katri Huitu, Venus Keus +1
The Froggatt-Nielsen mechanism is a well-motivated framework for generating the fermion mass hierarchy. This mechanism introduces flavons, complex scalars which are singlet under t…
Hidden strongly interacting massive particles
Matti Heikinheimo, Kasper Langaeble, Kimmo Tuominen
We consider dark matter as Strongly Interacting Massive Particles (SIMPs) in a hidden sector, thermally decoupled from the Standard Model heat bath. Due to its strong interactions,…
Prospects for indirect detection of frozen-in dark matter
Matti Heikinheimo, Tommi Tenkanen, Kimmo Tuominen
We study observational consequences arising from dark matter (DM) of non-thermal origin, produced by dark freeze-out from a hidden sector heat bath. We assume this heat bath was po…
Vacuum Stability and Perturbativity of SU(3) Scalars
Matti Heikinheimo, Kristjan Kannike, Florian Lyonnet +3
We calculate the vacuum stability conditions and renormalisation group equations for the extensions of standard model with a higher colour multiplet scalar up to the representation…
The Dawn of FIMP Dark Matter: A Review of Models and Constraints
Nicolás Bernal, Matti Heikinheimo, Tommi Tenkanen +2
We present an overview of scenarios where the observed Dark Matter (DM) abundance consists of Feebly Interacting Massive Particles (FIMPs), produced non-thermally by the so-called…