eXTP Overview
eXTP (enhanced X-ray Timing and Polarimetry Observatory) is the next flagship X-ray observatory designed to study matter and radiation under the most extreme conditions in the Universe. Its central science theme—“One Singularity, Two Stars, Three Extremes”—uses black holes, neutron stars, and possible quark stars to probe strong-field gravity, ultra-strong magnetic fields, and ultra-dense matter. By performing simultaneous spectral, timing, and polarimetric measurements, eXTP will connect the geometry, dynamics, and radiation physics of variable high-energy sources, while rapidly responding to transient and multi-messenger events.
eXTP combines large-area X-ray spectroscopy and fast timing with sensitive imaging polarimetry, wide-field transient monitoring, and measurements of the Cosmic X-ray Background. The main characteristics of the instruments are listed below:
| Instrument | Energy Range (keV) | Configuration | Effective area (cm²) |
| Spectroscopy Focusing Array (SFA) | 0.5-10 |
6 telescopes (5.25 m fl) |
>3000 (6 keV) |
| Polarimetry Focusing Array (PFA) | 2-10 |
3 telescopes (5.25 m fl) |
>350 (2 keV) |
| Wide-field Wide-band Camera (W2C) | 30-600 |
Coded mask imager |
>400 (60 keV, 48 DU) |
| Cosmic X-ray Background explorer (CXBe) | 10-100 | Collimator + shutter | ~250 (30 keV, 24 DU) |