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Updated: Aug 5, 2026
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Crust Glass Formation Reveals the Neutron Star Birth Properties in IGR J17480-2446
1Ioffe Institute, Politekhnicheskaya 26, 194021 Saint Petersburg, Russia.
Physical Review Letters
|July 31, 2026
Summary
IGR J17480-2446, a neutron star in a low-mass X-ray binary, shows unusual cooling and spin. Accretion likely formed a glass layer, indicating an early recycling stage for this accreting pulsar.
Area of Science:
- Astrophysics
- Neutron star physics
- X-ray astronomy
Background:
- IGR J17480-2446 is a low-mass X-ray binary system.
- It features an accreting pulsar (neutron star) with an unusual 11 Hz spin frequency.
- The system exhibits very slow post-outburst crust cooling.
Purpose of the Study:
- To investigate the cause of the slow crust cooling in IGR J17480-2446.
- To determine the mass of accreted material and confirm the neutron star's accretion stage.
- To analyze the neutron star's spin and thermal state for insights into its birth properties.
Main Methods:
- Analysis of X-ray emission and cooling curves.
- Modeling of crustal thermal conductivity.
- Accretion physics and neutron star evolution models.
Main Results:
- The slow cooling suggests a low thermal conductivity layer in the neutron star's outer crust, possibly composed of glass.
- Glass layer formation is attributed to accretion-induced failure of the crystalline crust.
- The accreted mass is estimated at ΔM≈2.4×10⁻⁶ M⊙, confirming an early accretion stage.
- The neutron star possesses birth properties typically associated with recycled pulsars.
Conclusions:
- The observed properties of IGR J17480-2446 are consistent with an early stage of neutron star recycling.
- The formation of a glassy crust layer is a natural consequence of accretion.
- The neutron star's peculiar properties may stem from formation in an electron-capture supernova.
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