Astronomers watched sleeping neutron star, NGC 7793 P13 coming back to life

P13, a neutron star undergoing supercritical accretion (Image: Ehime University)

Astronomers have tracked NGC 7793 P13 for over a decade consistently. The neutron star shows dramatic changes in X-ray brightness and rotation speed. It has become a key target for studying extreme astrophysical processes. Long-term observations reveal new insights into ultraluminous X-ray sources in galaxies.

Supercritical Accretion Powers Extreme Energy

Gas falls onto the star at extraordinary rates, forming accretion columns. These columns emit intense X-ray radiation from the star’s magnetic poles. The process explains how neutron stars achieve ultraluminous emission levels. Scientists study it to understand compact objects across the universe.

Brightness Fluctuations Observed Over Years

Between 2011 and 2024, P13’s luminosity changed more than 100-fold consistently. During 2021, the star entered a faint phase, dimming significantly. By 2022, X-ray emission rebounded, reaching record levels by 2024. These fluctuations help map interactions between matter and the star’s magnetic field.

Rotation Rate Follows Accretion

The star’s rotation speed accelerated and decelerated in line with brightness. Spin acceleration doubled during rebrightening events, showing column dynamics evolve. This demonstrates strong connection between accretion rate and rotational changes. Such observations offer clues about magnetic field and matter interactions.

Implications For Astrophysics Research

The findings provide new understanding of ultraluminous X-ray sources in detail. These findings inform models of supercritical accretion around neutron stars and black holes. P13 exemplifies how compact objects can produce extreme energy outputs. It highlights dynamic, high-energy processes occurring in nearby galaxies.

Future Monitoring And Discoveries

Ongoing observations will track long-term cycles of brightness and spin consistently. Astronomers plan to combine X-ray, optical, and radio data for deeper insights. Study on these systems helps predict behaviour of other ultraluminous X-ray sources. NGC 7793 P13 remains a laboratory for extreme stellar physics research continuously.