COMPACT

“Understanding gravity using a COMprehensive search for fast-spinning Pulsars And CompacT binaries” (COMPACT) is an ERC starting grant project in Astrophysics, hosted at the Max Planck Institute for Radio Astronomy from May 01, 2023. The project was awarded to Dr. Vivek Venkatraman Krishnan and runs for a duration of 5 years.

COMPACT aims to further our understanding of gravity and nuclear physics through discoveries of highly relativistic binary pulsar systems and ultra-fast spinning pulsars. These discoveries are done via a tailor made, targeted pulsar search survey with observation of dense clusters of stars called Globular Clusters.

Pulsars - rotating neutron stars that emit radio light along its magnetic poles - are some of the densest objects in the Universe. A teaspoon of neutron star matter can weigh as much as Mount Everest. It is impossible to create such high densities on Earth, so astronomical observations provide the only way of understanding ultra-dense matter. When these pulsars are in binary systems with another star, they exhibit relativistic orbital effects that can be measured and compared with the predictions from theories of gravity such as Einstein’s General Relativity. Such tests provide the rare possibility to understand if, when and where nature deviates from Einstein’s predictions. COMPACT aims to discover sources that are best suited to help in these endeavors. COMPACT will employ novel signal processing algorithms to find pulsars in very short orbital period binary systems, and pulsars that spin extremely fast (of the order of a millisecond or less). Such COMPACT discoveries are also natural gravitational wave emitters; a significant fraction of which would inevitably be detected by current or future gravitational wave detectors, thereby providing crucial multi-messenger constraints for such detections.

COMPACT will use two of the most sensitive radio telescopes in the world for this endeavor – The 100-m Effelsberg telescope in Germany, and the MeerKAT radio interferometer in South Africa.