Related papers: Stellar Evolution confronts Axion Models
Cosmological structure formation simulations of ultralight axion-like dark matter have shown that an axion star forms at the center of every dark matter halo in the Universe. These axion stars would then form in large numbers during the…
The status of the art for evolutionary models of low mass, population II stars is revisited, stressing the need for the models to be preliminarily tested with suitable observational data. The uncertainties still affecting the theory are…
Cosmologically stable, light particles that came into thermal contact with the Standard Model in the early universe may persist today as a form of hot dark matter. For relics with masses in the eV range, their role in structure formation…
The PVLAS signal has renewed the interest in light bosons coupled to the electromagnetic field. However, astrophysical bounds coming from the lifetime of the sun and the CAST experiment are seemingly in conflict with this result. We discuss…
We study the feasibility of a new generation axion helioscope, the most ambitious and promising detector of solar axions to date. We show that large improvements in magnetic field volume, x-ray focusing optics and detector backgrounds are…
We investigate the production of photons from coherently oscillating, spatially localized clumps of axionic fields (oscillons and axion stars) in the presence of external electromagnetic fields. We delineate different qualitative behaviour…
Axions and other light particles appear ubiquitously in physics beyond the Standard Model, with a variety of possible couplings to ordinary matter. Cosmology offers a unique probe of these particles as they can thermalize in the hot…
For the first time, we predict the axion spectra and their associated luminosities for several low-mass stars -- one and two solar masses stars in the main sequence and post-main sequence stages of evolution. Equally, we also compute the…
Stellar model atmospheres form the basis for any element abundance determination and hence are crucial ingredients for studies of stellar, galactic and cosmic evolution. With recent observational progress with the advent of 8m-class…
Low-mass particles such as neutrinos, axions, other Nambu-Goldstone bosons and gravitons are produced in the hot and dense interior of stars. Therefore, astrophysical arguments constrain the properties of these particles in ways which are…
The International Axion Observatory (IAXO) is a forth generation axion helioscope designed to detect solar axions and axion-like particles (ALPs) with a coupling to the photon $g_{a\gamma}$ down to a few $10^{-12}$ GeV$^{-1}$, 1.5 orders of…
In spite of the great effort made in the last decades to improve our understanding of stellar evolution, significant uncertainties remain due to our poor knowledge of some complex physical processes that require an empirical calibration,…
Axions and axion-like particles (ALPs) have gained immense attention in searches for beyond Standard Model (BSM) physics. Experiments searching for axions leverage their predicted couplings to Standard Model (SM) particles to look for…
Spectral evolution models are a widely used tool for determining the stellar content of galaxies. I provide a review of the latest developments in stellar atmosphere and evolution models, with an emphasis on massive stars. In contrast to…
A finite axion-nucleon coupling enables the production of axions in stellar environments via the thermal excitation and subsequent de-excitation of the $^{57}$Fe isotope. Given its low-lying excited state at 14.4 keV, $^{57}$Fe can be…
Axions as dark matter is an increasingly important subject in astrophysics and cosmology. Experimental and observational searches are mounting across the mass spectrum of axion-like particles, many of which require detailed knowledge of…
Many theoretically well-motivated extensions of the Standard Model of particle physics predict the existence of the axion and further ultralight axion-like particles. They may constitute the mysterious dark matter in the universe and solve…
We calculate the axion emission rate from reactions involving thermal pions in matter encountered in supernovae and neutron star mergers, identify unique spectral features, and explore their implications for astrophysics and particle…
The observed properties of stars and especially the neutrino signal of the supernova 1987A provide an upper limit to the axion mass, while the age and expansion rate of the universe provide a lower limit. There remains a "window of…
The understanding and modeling of the structure and evolution of stars is based on statistical physics as well as on hydrodynamics. Today, a precise identification and proper description of the physical processes at work in stellar…