Chinese and Australian astrophysicists have discovered that neutron stars’ birth rates can be described by a unimodal distribution that smoothly turns on at a solar mass of 1.1 and peaks before declining as a sudden power method.
Impressions of the artist of Neutron Star. Image credit: Sci.News.
Neutron stars are dense remnants of giant stars, more than eight times as huge remnants as our Sun, born at the end of life with the explosion of a brilliant supernova.
These incredibly dense objects have a mass of one to twice the mass of the sun, compressed into a ball of the size of a city with a radius of just 10 km.
Astronomers usually only weigh the neutron stars (which measure how big they are) and are found in binary star systems with different objects, such as white d stars or other neutron stars.
However, in these systems, the first born neutron stars acquire extra mass from their peers through a process called attachment, making it difficult to determine the original birth amount.
“Understanding the birth mass of neutron stars is key to unlocking the history of their formation,” says Dr. Simon Stevenson, an Ozgrav researcher at Swinburne University.
“This work provides an important basis for interpreting gravitational wave detection in neutron star mergers.”
Dr. Stevenson and his colleagues analyzed samples of 90 neutron stars in the binary star system and considered the masses obtained from the birth of each neutron star to measure the distribution of neutron star masses at birth.
They discovered that neutron stars are usually born with a mass of about 1.3 solar masses, with heavier neutron stars being more rare.
“Our approach allows us to finally understand the mass of neutron stars at birth. This has been a long-standing question in astrophysics,” said Professor Xingjiang Zhu of Beijing Normal University.
“This discovery is important for interpreting new observations of neutron star masses from observations of gravitational waves.”
study It will be displayed in the journal Natural Astronomy.
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ZQ. you et al. Determination of the birth mass function of neutron stars from observations. Nut AthlonPublished online on February 26th, 2025. doi:10.1038/s41550-025-02487-w
Source: www.sci.news