Abstract
White dwarf (WD) stars may radiate keV-energy axions produced in their stellar cores. This has been extensively studied as an extra channel by which WDs may cool, with some analyses even suggesting that axions can help explain the observed WD luminosity function. We show that the radiated axions may convert into x rays in the strong magnetic fields surrounding the WDs, leading to observable x-ray signatures. We use Suzaku observations of the WD RE J0317-853 to set the strongest constraints to date on the combination of the axion-electron (g_{aee}) times axion-photon (g_{aγγ}) couplings, and we show that dedicated observations of magnetic WDs by telescopes such as Chandra, XMM-Newton, and NuSTAR could increase the sensitivity to |g_{aee}g_{aγγ}| by over an order of magnitude, allowing for a definitive test of the axionlike-particle explanation of the stellar cooling anomalies.
Highlights
The quantum chromodynamics (QCD) axion, originally proposed to solve the strong CP problem [1,2,3,4], is a wellmotivated extension of the standard model of particle physics
It has been suggested that the observed white dwarf (WD) luminosity function prefers the existence of an axion [8,9], a claim further supported by period-drift measurements of WDs undergoing pulsations [11]
We show that x-ray telescope observations of magnetic white dwarf (WD) stars (MWDs) have the potential to probe a wide range of axion masses and couplings
Summary
The quantum chromodynamics (QCD) axion, originally proposed to solve the strong CP problem [1,2,3,4], is a wellmotivated extension of the standard model of particle physics. In this work we present a novel method, using x-ray observations of magnetic white dwarf (WD) stars (MWDs), to probe the existence of axions.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
