Related papers: Stellar Evolution Bounds on the ALP-Photon Couplin…
X-ray telescopes are an exceptional tool for searching for new fundamental physics. In particular, X-ray observations have already placed world-leading bounds on the interaction between photons and axion-like particles (ALPs). ALPs are…
Axion Like Particles (ALPs), postulated to solve the strong-CP problem, are predicted to couple with photons in the presence of magnetic fields, which may lead to a significant change in the observed spectra of gamma-ray sources such as…
Current models of galaxy evolution suggest that feedback from active galactic nuclei is needed to explain the high-luminosity cutoff in the galaxy luminosity function. Exactly how an AGN outflow couples with the ambient medium and…
A multiwavelength study of galaxies is important to understand their formation and evolution. Only in the recent past, thanks to the Atacama Large (Sub) Millimeter Array (ALMA), were we able to study the far-infrared (IR) properties of…
Open and globular star clusters have served as benchmarks for the study of stellar evolution due to their supposed nature as simple stellar populations of the same age and metallicity. After a brief review of some of the pioneering work…
If axions or other low-mass pseudoscalars couple to electrons (``fine structure constant'' $\alpha_a$) they are emitted from red giant stars by the Compton process $\gamma+e\to e+a$ and by bremsstrahlung $e+(Z,A)\to (Z,A)+e+a$. We construct…
The post-asymptotic giant branch (AGB) phase is arguably one of the least understood phases of the evolution of low- and intermediate- mass stars. The recent post-AGB evolutionary sequences computed by Miller Bertolami (2016) are at least…
The binary star alpha Aurigae (otherwise known as Capella) is extremely important to understand the core hydrogen and helium burning phases of the stars, as the primary star is likely evolving through the core helium burning phase, and the…
The Peccei-Quinn mechanism proposed to solve the CP problem of Quantum Chromodynamics has as consequence the existence of axions, hypothetical weakly interacting particles whose mass is constrained to be on the sub-eV range. If these…
Information about the space-time evolution of colliding nuclei can be extracted correlating particles emitted from nuclear collisions. The high density of particles produced in the STAR experiment allows the measurement of non-identical…
In this work, for the first time, we use seismic data as well as surface abundances to model the supergiant $\alpha$-Ori, with the goal of setting an upper bound on the axion-photon coupling constant $g_{a\gamma}$. We found that, in…
Stars are powerful sources for weakly interacting particles that are produced by nuclear or plasma processes in their hot interior. These fluxes can be used for direct measurements (e.g. solar or supernova neutrinos) or the back-reaction on…
We study axion-like particles (ALPs) whose dominant interactions are with gluons and third-generation quarks, and whose couplings to light Standard Model (SM) particles arise at one loop. These loop-induced effects lead to ALP decays and…
We interpret the recent excess in a rare decay of the Higgs boson, $H\to Z\gamma$, using a light axion-like particle (ALP) in the massrange $0.05 - 0.1$ GeV.The dominant decay of such a light ALP is into a pair of collimated photons, whose…
We study the AGN-host co-evolution issue here by focusing on the correlation between the hard X-ray emission from central AGNs and the stellar populations of the host galaxies. By focusing on the galaxies with strong H$\alpha$ line emission…
We explore the evolution of collisionally merged stars in the blue straggler region of the HR diagram. The starting models for our stellar evolution calculations are the results of the smoothed particle hydrodynamics (SPH) simulations of…
Several laboratory experiments have published limits on axionlike particles (ALPs) with feeble couplings to electrons and masses in the keV-MeV range, under the assumption that such ALPs comprise the dark matter. We note that ALPs decay…
In a first paper, HIPPARCOS astrometric and kinematic data were used to calibrate both infrared K and IRAS luminosities at the same time as kinematic parameters of Long Period Variable stars (LPVs). Individual estimated absolute magnitudes…
A fundamental goal of modern-day astrophysics is to understand the connection between supermassive black hole (SMBH) growth and galaxy evolution. Merging galaxies offer one of the most dramatic channels for galaxy evolution known, capable…
The nebular evolution is followed from the vicinity of the asymptotic-giant branch across the Hertzsprung-Russell diagram until the white-dwarf domain is reached, using various central-star models coupled to different initial envelope…