On the 5th, the Chinese Academy of Sciences held a press conference to release the operation of China's Tianyan FAST and a series of important scientific achievements. Since its completion, China Tianyan FAST has continuously improved its operational efficiency and quality, with an annual observation time of more than 5,300 hours. So far, FAST has discovered about 500 pulsars, making it the most efficient device in the world since its operation.
FAST neutral hydrogen spectroscopy has made significant progress in measuring interstellar magnetic fields
Neutral hydrogen is the most abundant element in the universe, widely present at different times in the universe, and is one of the best tracers for the distribution of matter at different scales. The international collaborative team led by the National Astronomical Observatory used an original neutral hydrogen narrow-line self-absorption method to obtain high-confidence Zeeman effect measurements in the nuclear envelope of protostars for the first time using FAST. The discovery of a coherent magnetic field structure in the interstellar medium from cold neutral gas to protostar nuclei is different from the prediction of the Standard Model, providing important observational evidence for solving the "magnetic flux problem", one of the three classical problems of star formation. The results were officially published in the form of a cover article in the international academic journal Nature on January 6, 2022, Beijing time.
Obtain samples of the largest rapid radio burst event to date
Fast radio bursts (FRBs) are the brightest radio bursts in the universe, with unknown origins, and are the latest hotspots in astronomy. The international cooperation team led by the National Astronomical Observatory used FAST to observe fast radio burst FRB121102, detected 1652 burst events in about 50 days, obtained the largest sample of fast radio burst event to date, exceeded the total number of burst events published in all previous articles in the field, and revealed for the first time the complete energy spectrum of fast radio bursts and their bimodal structure.
The "Silver Road Surface Pulsar Snapshot Survey" project continues to discover millisecond pulsars
The discovery of pulsars is one of the main scientific targets of observations by large international radio telescopes. FAST's major priority project "Silver Road Surface Pulsar Snapshot Survey" has completed 8% of the planned search for the sky area in less than two years, accumulatively observing about 620 machines, and so far the project has discovered 279 new pulsars, of which 65 are millisecond pulsars and 22 in binary systems. The number of pulsars discovered in the year and a half of the work has surpassed the results of a 15-year search by the Arecibo Telescope in the United States.
Multi-band cooperative observations open up new directions for pulsar searches
Based on the international leading advantage of FAST sensitivity, the combination of FAST with the Fermi Gamma-ray Observatory's Large Field Telescope, an important space astronomical facility in the high-energy band, for space-earth integration coordination and follow-up observation, has the potential to produce major scientific breakthroughs. The research team discovered multiple pulsars and conducted multi-band observational analysis. Multi-band cooperative observation not only opens up a new direction for FAST pulsar search, but also opens up a new way to study the electromagnetic radiation mechanism of pulsars, providing more samples for the evolution of sub-star families and the detection of gravitational waves.
Based on the obvious advantages of ultra-high sensitivity, FAST has become a sharp tool in the field of medium and low frequency radio astronomy, and will produce scientific achievements to deepen human understanding of the universe in the direction of the origin and physical mechanism of fast radio bursts, neutral hydrogen universe research, pulsar search and physical research, pulsar timing and low-frequency gravitational wave detection.
It is planned to open 1% of the observation time to primary and secondary school students nationwide in 2022
It is understood that fast priority and major scientific projects in 2021 account for 50% of the total observation time. Since FAST was officially opened to the world, 27 international projects in 14 countries were approved and scientific observations were launched in August 2021. In the future, FAST will continue to operate with high quality, carry out scientific observations such as searching for pulsars and detecting gravitational waves, and plans to open 1% of the observation time to primary and secondary school students across the country in 2022, and primary and secondary school students will put forward scientific ideas and be helped by astronomers to help them realize them.
Chang Jin, academician of the Chinese Academy of Sciences and director of the National Astronomical Observatory, introduced that in future observations, FAST will be committed to finding sub-millisecond pulsars of less than 1 millisecond, which is also a system that the world is looking for; the second is to look for double stars composed of pulsars and black holes; the third point is the neutral hydrogen survey, which is the most advantageous place of FAST, its sensitivity is high, and it is expected to achieve major results in neutral hydrogen survey.
(CCTV reporter Shuai Junquan)