We present the first X-ray polarimetric measurement of the neutron star low-mass X-ray binary system AX J1745.6−2901 conducted by the Imaging X-ray Polarimetry Explorer (IXPE) satellite. This transient source, located within ∼1 (Formula presented) .′ 5 of the Galactic center, was observed serendipitously during a MAXI J1744−294 observation with a duration of 150 ks. The complex nature of the region in which AX J1745.6−2901 is located poses a challenge for studying its polarization. By performing a detailed analysis of the contamination from MAXI J1744−294 and the Galactic center diffuse emission, we find the source polarization degree PD = 14.7% ± 4.0% and polarization angle PA = 122° ± 8°. The phase-resolved analysis shows increase in polarization during the eclipse phase, with PD = 34.2% ± 8.7%, suggesting that the polarization-inducing mechanisms are of scattering nature, probably originating from disk winds.
Mikušincová, R., Marra, L., Manikantan, H., Bianchi, S., Capitanio, F., Chakraborty, S., et al. (2026). The First X-Ray Polarimetry of an Eclipsing Low-mass X-Ray Binary: Serendipitous IXPE Observation of AX J1745.6–2901. THE ASTROPHYSICAL JOURNAL, 1005(1) [10.3847/1538-4357/ae7341].
The First X-Ray Polarimetry of an Eclipsing Low-mass X-Ray Binary: Serendipitous IXPE Observation of AX J1745.6–2901
Marra, Lorenzo;Bianchi, Stefano;Ciancarella, Raul;Gianolli, Vittoria E.;Gnarini, Andrea;Matt, Giorgio;Parra, Maxime;Taverna, Roberto;Ursini, Francesco;
2026-01-01
Abstract
We present the first X-ray polarimetric measurement of the neutron star low-mass X-ray binary system AX J1745.6−2901 conducted by the Imaging X-ray Polarimetry Explorer (IXPE) satellite. This transient source, located within ∼1 (Formula presented) .′ 5 of the Galactic center, was observed serendipitously during a MAXI J1744−294 observation with a duration of 150 ks. The complex nature of the region in which AX J1745.6−2901 is located poses a challenge for studying its polarization. By performing a detailed analysis of the contamination from MAXI J1744−294 and the Galactic center diffuse emission, we find the source polarization degree PD = 14.7% ± 4.0% and polarization angle PA = 122° ± 8°. The phase-resolved analysis shows increase in polarization during the eclipse phase, with PD = 34.2% ± 8.7%, suggesting that the polarization-inducing mechanisms are of scattering nature, probably originating from disk winds.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
