Science and Tech

And if there is no ring in the EHT data of the center of the galaxy M87

Radio images obtained from the reanalysis, showing the center of the elliptical galaxy M87.

Radio images obtained from the reanalysis, showing the center of the elliptical galaxy M87. – MIYOSHI ET AL

June 30. () –

A new independent analysis of Event Horizon Telescope (EHT) observational data for the center of the elliptical galaxy M87 has produced images with different characteristics.

Radio observation data from the center of the elliptical galaxy M87 obtained by the Event Horizon Telescope in April 2017 –published in 2019– and the methods by which the data was analyzed have been made publicly available throughout the world.

Investigators not involved in the EHT have independently reanalyzed these data and methods, thus validating the results presented by the EHT. In fact, several teams have published their detailed reanalysis results in research papers.

A research team consisting of Makoto Miyoshi (Assistant Professor at NAOJ (National Astronomical Observatory of Japan), Yoshiaki Kato (Recruited Researcher at RIKEN at the time of the study), and Junichiro Makino (Professor at Kobe University) re-analyzed the data. of M87 with standard tools and investigated the nature of the data. He publishes results in The Astrophysical Journal.

Instead of the ring structure observed by the EHT, the resulting images show a “core” in the galactic center, in addition to the astrophysical jet that extends from the core and the “knots” that apparently form part of the jet.

Many supermassive black holes emit astrophysical jets; the one that extends from the center of M87 has been known for more than 100 years, having been studied numerous times. The research team believes that it is the basis of this jet that their analysis has resolved.

The team notes that the 40-microarcsecond (1/25,000th of an arcsecond) ring structure seen in the EHT image is likely the result of insufficient data to resolve 40-microarcsecond structures, compared to the data for structures of other sizes, due to fewer telescopes involved in EHT observations at the time.

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