Line detections in photospheric radius expansion bursts from 4U 1820-303
Line detections in photospheric radius expansion bursts from 4U 1820-303
Context: NICER (Neutron star Interior Composition ExploreR) is the instrument of choice for the spectral analysis of type I X-ray bursts, as it provides high throughput at X-ray CCD resolution, down to 0.3 keV. Aims: This study investigates whether the energies of absorption lines detected in photospheric radius expansion (PRE) …