Researchers Tanmay Kumar Poddar, Sourov Roy, and Pratick Sarkar from the Indian Association for the Cultivation of Science in Kolkata, India, have delved into the intriguing world of dark photons and their potential interactions with visible light photons in extreme astrophysical environments. Their work, published in the journal Physical Review Letters, explores the implications of these interactions for our understanding of the universe and the energy sector.
Dark photons, or dark sector photons, are hypothetical particles that are thought to interact only weakly with ordinary matter. They are a compelling candidate for dark matter, which is believed to make up approximately 27% of the universe’s content but remains largely undetected. In their study, the researchers focused on the phenomenon of photon-dark photon oscillation, where a visible light photon can transform into a dark photon and vice versa, under specific conditions.
The team investigated this process in the intense magnetic and plasma environments surrounding compact astrophysical objects like neutron stars and black holes. They found that the complex, non-monotonic plasma density profiles in these environments can significantly enhance the resonant conversion between visible light photons and dark photons. This enhancement leads to stronger constraints on the photon-dark photon kinetic mixing parameter, a measure of how much these particles can intermingle.
By analyzing spectral data from the supermassive black hole M87* and the Crab pulsar-wind Nebula, the researchers derived new bounds on the photon-dark photon coupling. For M87*, they found a constraint of approximately 7×10^-6 at a dark photon mass of about 5×10^-7 electron volts (eV) for an oscillation distance of three times the photon sphere radius. For the Crab pulsar-wind Nebula, they obtained an even stronger constraint of approximately 8×10^-7 at a dark photon mass of about 4×10^-9 eV for oscillation baselines of around 1,000 kilometers.
While these constraints are not the strongest ever obtained, they are notable for being derived from realistic plasma backgrounds. Moreover, the researchers suggest that observations of compact objects with larger surface magnetic fields and measurements of photon spectra at lower frequencies could significantly improve these limits. This could have important implications for the energy sector, as a better understanding of dark photons and their interactions could potentially lead to new energy technologies or more efficient energy generation methods.
In the meantime, this research highlights the value of studying extreme astrophysical environments to probe fundamental physics and advance our understanding of the universe. As the researchers continue to refine their models and analyze new data, we can expect to learn even more about the enigmatic world of dark photons and their role in the cosmos.
Source: Poddar, T. K., Roy, S., & Sarkar, P. (2023). Photon-dark photon oscillation in M87 and Crab Nebula environments. Physical Review Letters, 130(1), 011001.
This article is based on research available at arXiv.