Abstract
Laser-based searches of the yet unobserved vacuum birefringence might be sensitive for very light hypothetical particles carrying a tiny fraction of the electron charge. We show that, with the help of contemporary techniques, polarimetric investigations driven by an optical laser pulse of moderate intensity might allow for excluding regions of the parameter space of these particle candidates which have not been discarded so far by laboratory measurement data. Particular attention is paid to the role of a Gaussian wave profile. It is argued that, at energy regimes in which the vacuum becomes dichroic due to these minicharges, the transmission probability of a probe beam through an analyzer set crossed to the initial polarization direction will depend on both the induced ellipticity as well as the rotation of the initial polarization plane. The weak and strong field regimes, relative to the attributes of these minicharged particles, and the relevance of the polarization of the strong field are investigated.
Highlights
The Standard Model of particle physics is currently understood as an effective theory, where charge quantization seems to be conceived as a fundamental principle
We have studied the prospects that laser-based experiments, designed to detect vacuum birefringence, offer for probing hypothetical degrees of freedom with a tiny fraction of the electron charge
Throughout this investigation, we have indicated that the vacuum of Mini-Charged Particles (MCPs) might induce ellipticity and rotation on the incoming polarization plane, even though the probe photon energy is much below the threshold of electron-positron pair production
Summary
The Standard Model of particle physics is currently understood as an effective theory, where charge quantization seems to be conceived as a fundamental principle. We are only interested in asymptotically large spacetime distances [φ → ∞], i.e., when the high-intensity laser field is turned off, which restores the original integration limits Inserting this expression into Eq (8) and taking into account the tensorial decomposition of the polarization tensor [see Eq (5)], we end up with 1 |δθ(ǫ, mǫ)| ≈ 2 sin(2θ0). Using high-purity polarimetric techniques for xrays [66, 67] (QED) vacuum birefringence could be measured with a similar setup by combining a x-ray probe and a strong optical field [QED-induced dichroism is exponentially small, δθQED = 0 for practical purposes] Such an experiment is envisaged at HIBEF [46]. Nshot counts the number of laser shots used for a measurement, T denotes the transmission coefficient of all optical components and Nin is the number of incoming x-ray probe photons, respectively
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
