140 citations · 856 across the 26 of their papers we have counts for
26 papers
Thermodynamics of oscillating neutrinos
Lucas Johns
The title theory is formulated. It entails a quantum-coherent variant of the Fermi-Dirac distribution and casts new light on neutrino oscillations. It might enable the incorporatio…
Neutrino many-body correlations
Lucas Johns
This paper responds to suggestions that the standard approach to collective neutrino oscillations leaves out potentially important quantum many-body correlations. Arguments in favo…
Collisional flavor instability in dense neutrino gases
Zewei Xiong, Lucas Johns, Meng-Ru Wu +1
Charged-current neutrino processes such as and destroy the flavor coherence among the weak-interaction…
Evolution of collisional neutrino flavor instabilities in spherically symmetric supernova models
Zewei Xiong, Meng-Ru Wu, Gabriel Martínez-Pinedo +4
We implement a multi-group and discrete-ordinate neutrino transport model in spherical symmetry which allows to simulate collective neutrino oscillations by including realistic col…
Collisional instabilities of neutrinos and their interplay with fast flavor conversion in compact objects
Lucas Johns, Zewei Xiong
Fast and collisional flavor instabilities possibly occur in the neutrino decoupling regions of core-collapse supernovae and neutron-star mergers. To gain a better understanding of…
Self-consistency in models of neutrino scattering and fast flavor conversion
Lucas Johns, Hiroki Nagakura
Several recent numerical studies have examined the effects of neutrino neutral-current scattering on fast flavor conversion (FFC). Those studies are in apparent conflict, with some…
Where, when and why: occurrence of fast-pairwise collective neutrino oscillation in three-dimensional core-collapse supernova models
Hiroki Nagakura, Lucas Johns, Adam Burrows +1
Fast-pairwise collective neutrino oscillation represents a key uncertainty in the theory of core-collapse supernova (CCSN). Despite the potentially significant impact on CCSN dynam…
Geometric and Majorana phases in neutrino oscillations
Lucas Johns
Geometric (Aharonov--Anandan) phases in neutrino oscillations have been claimed [Phys. Lett. B 780 (2018) 216] to be sensitive to the Majorana phases in neutrino mixing. More recen…
New method for detecting fast neutrino flavor conversions in core-collapse supernova models with two-moment neutrino transport
Hiroki Nagakura, Lucas Johns
Fast-pairwise neutrino oscillations potentially affect many aspects of core-collapse supernova (CCSN): the explosion mechanism, neutrino signals, and nucleosynthesis in the ejecta.…
Fast flavor instabilities and the search for neutrino angular crossings
Lucas Johns, Hiroki Nagakura
With the recognition that fast flavor instabilities likely affect supernova and neutron-star-merger neutrinos, using simulation data to pin down when and where the instabilities oc…
Collisional flavor instabilities of supernova neutrinos
Lucas Johns
A lingering mystery in core-collapse supernova theory is how collective neutrino oscillations affect the dynamics. All previously identified flavor instabilities, some of which mig…
Constructing angular distributions of neutrinos in core collapse supernova from zero-th and first moments calibrated by full Boltzmann neutrino transport
Hiroki Nagakura, Lucas Johns
Two-moment neutrino transport methods have been widely used for developing theoretical models of core-collapse supernova (CCSN), since they substantially reduce the computational b…
The Hydrogen Mixing Portal, Its Origins, and Its Cosmological Effects
Lucas Johns, Seth Koren
Hydrogen oscillation into a dark-sector state has recently been proposed as a novel mechanism through which hydrogen can be cooled during the dark ages -- without direct coupl…
Hydrogen Mixing as a Novel Mechanism for Colder Baryons in 21 cm Cosmology
Lucas Johns, Seth Koren
The anomalous 21 cm absorption feature reported by EDGES has galvanized the study of scenarios in which dark matter (DM) siphons off thermal energy from the Standard Model (SM) gas…
Fast oscillations, collisionless relaxation, and spurious evolution of supernova neutrino flavor
Lucas Johns, Hiroki Nagakura, George M. Fuller +1
Mounting evidence indicates that neutrinos likely undergo fast flavor conversion (FFC) in at least some core-collapse supernovae. Outcomes of FFC, however, remain highly uncertain.…
Neutrino oscillations in supernovae: angular moments and fast instabilities
Lucas Johns, Hiroki Nagakura, George M. Fuller +1
Recent theoretical work indicates that the neutrino radiation in core-collapse supernovae may be susceptible to flavor instabilities that set in far behind the shock, grow extremel…
Derivation of the sterile neutrino Boltzmann equation from quantum kinetics
Lucas Johns
An extensive, growing body of work has been penned on cosmologies that include one or more sterile neutrinos. Early entries in the literature formulated a Boltzmann-like equation d…
Neutrino oscillations in a trapping potential
Lucas Johns
A number of derivations of the standard neutrino oscillation formula are known, each one providing its own unique insights. Common to all treatments is the assumption that neutrino…
Self-interacting sterile neutrino dark matter: the heavy-mediator case
Lucas Johns, George M. Fuller
For active-sterile mixing to be responsible for the full relic abundance of dark matter additional new physics is needed beyond the keV-scale sterile neutrino itself. The extra ing…
Catching Element Formation In The Act
Chris L. Fryer, Frank Timmes, Aimee L. Hungerford +216
Gamma-ray astronomy explores the most energetic photons in nature to address some of the most pressing puzzles in contemporary astrophysics. It encompasses a wide range of objects…
Time's arrow and life's origin
Lucas Johns
The thermodynamic arrow-of-time problem is thought to be resolved by the observation that our universe initially was---and still is---far from equilibrium. The psychological arrow-…
Strange mechanics of the neutrino flavor pendulum
Lucas Johns, George M. Fuller
We identify in the flavor transformation of astrophysical neutrinos a new class of phenomena, a common outcome of which is the suppression of flavor conversion. Appealing to the eq…
Geometric phases in neutrino oscillations with nonlinear refraction
Lucas Johns, George M. Fuller
Neutrinos propagating in dense astrophysical environments sustain nonlinear refractive effects due to neutrino-neutrino forward scattering. We study geometric phases in neutrino os…
An optimization-based approach to calculating neutrino flavor evolution
Eve Armstrong, Amol V. Patwardhan, Lucas Johns +3
We assess the utility of an optimization-based data assimilation (D.A.) technique for treating the problem of nonlinear neutrino flavor transformation in core collapse supernovae.…