Discovery of thermonuclear Type-I X-ray bursts from the X-ray binary MAXI J1807+132

• Autores: Albayati, A. C.; Altamirano, D.; Jaisawal, G. K.; Bult, P.; Rapisarda, S.; Mancuso, Giulio Cesare; Güver, T.; Arzoumanian, Z.; Chakrabarty, D.; Chenevez, J.; Court, J. M. C.; Gendreau, K. C.; Guillot, S.; Keek, L.; Malacaria, C.; Strohmayer, T. E.
• Año de publicación: 2021
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: STARS: INDIVIDUAL (MAXI J1807+132); STARS: NEUTRON; X-RAYS: BINARIES; X-RAYS: BURSTS
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

MAXI J1807+132 is a low-mass X-ray binary (LMXB) first detected in outburst in 2017. Observations during the 2017 outburst did not allow for an unambiguous identification of the nature of the compact object. MAXI J1807+132 that was detected in outburst again in 2019 and was monitored regularly with Neutron Star Interior Composition Explorer(NICER). In this paper, we report on 5 days of observations during which we detected three thermonuclear (Type-I) X-ray bursts, identifying the system as a neutron star LMXB. Time-resolved spectroscopy of the three Type-I bursts revealed typical characteristics expected for these phenomena. All three Type-I bursts show slow rises and long decays, indicative of mixed H/He fuel. We find no strong evidence that any of the Type-I bursts reached the Eddington Luminosity; however, under the assumption that the brightest X-ray burst underwent photospheric radius expansion, we estimate a <12.4 kpc upper limit for the distance. We searched for burst oscillations during the Type-I bursts from MAXI J1807+132 and found none (<10 per cent amplitude upper limit at 95 per cent confidence level). Finally, we found that the brightest Type-I burst shows a ∼1.6 s pause during the rise. This pause is similar to one recently found with NICER in a bright Type-I burst from the accreting millisecond X-ray pulsar SAX J1808.4-3658. The fact that Type-I bursts from both sources can show this type of pause suggests that the origin of the pauses is independent of the composition of the burning fuel, the peak luminosity of the Type-I bursts, or whether the NS is an X-ray pulsar.
Fil: Albayati, A. C.. University of Southampton; Reino Unido
Fil: Altamirano, D.. University of Southampton; Reino Unido
Fil: Jaisawal, G. K.. Technical University of Denmark; Dinamarca
Fil: Bult, P.. University of Maryland; Estados Unidos
Fil: Rapisarda, S.. Shanghai Astronomical Observatory Chinese Academy Of Sciences; China
Fil: Mancuso, Giulio Cesare. Universidad Nacional de La Plata; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; Argentina
Fil: Güver, T.. Istanbul Üniversitesi; Turquía
Fil: Arzoumanian, Z.. Nasa Goddard Space Flight Center; Estados Unidos
Fil: Chakrabarty, D.. MIT Kavli Institute For Astrophysics And Space Research; Estados Unidos
Fil: Chenevez, J.. Technical University of Denmark; Dinamarca
Fil: Court, J. M. C.. Texas Tech University; Estados Unidos
Fil: Gendreau, K. C.. Nasa Goddard Space Flight Center; Estados Unidos
Fil: Guillot, S.. Universite de Toulouse; Francia
Fil: Keek, L.. NASA Marshall Space Flight Cente; Estados Unidos
Fil: Malacaria, C.. NASA Marshall Space Flight Cente; Estados Unidos
Fil: Strohmayer, T. E.. Nasa Goddard Space Flight Center; Estados Unidos