AstroSat's view of 4U 1735-44: spectral, temporal, and type I X-ray burst studies

Title

AstroSat's view of 4U 1735-44: spectral, temporal, and type I X-ray burst studies

Creator

Lavanya S.; Thomas N.T.; Gudennavar S.B.; Bubbly S.G.

Description

This study utilizes the simultaneous broad-band observations of 4U 1735-44 from AstroSat, offering enhanced spectral and temporal resolution, to investigate its spectral properties, temporal behaviour, and burst characteristics. Spectral, type I X-ray burst, and temporal analyses on 4U 1735-44 were performed using AstroSat/Soft X-ray Telescope and Large Area X-ray Proportional Counter (LAXPC) observations. The hardness-intensity diagram from LAXPC-20 showed a positive correlation between hardness and intensity, with a pattern resembling the banana branch typical of atoll sources. Spectral analysis carried out in the 0.7-20.0 keV energy range, using the model combination - (), suggested a cool accretion disc truncated at a large distance from the neutron star in the system. Time-resolved spectral studies of two type I X-ray bursts detected from the source revealed evidence of photospheric radius expansion, allowing for an estimation of the source distance. Temporal analysis showed the presence of low-frequency quasi-periodic oscillation at 69 Hz (3.3 significance with more than 99 per cent confidence) and prominent noise features below 30 Hz. 2024 The Author(s).

Source

Monthly Notices of the Royal Astronomical Society, Vol-534, No. 3, pp. 2783-2794.

Date

2024-01-01

Publisher

Oxford University Press

Subject

accretion, accretion discs; stars: neutron; X-rays: binaries; X-rays: bursts; X-rays: individual: 4U 1735-44

Coverage

Lavanya S., Department of Physics and Electronics, CHRIST University, Karnataka, Bangalore, 560029, India; Thomas N.T., Department of Physics and Electronics, CHRIST University, Karnataka, Bangalore, 560029, India; Gudennavar S.B., Department of Physics and Electronics, CHRIST University, Karnataka, Bangalore, 560029, India; Bubbly S.G., Department of Physics and Electronics, CHRIST University, Karnataka, Bangalore, 560029, India

Rights

All Open Access; Gold Open Access

Relation

ISSN: 358711; CODEN: MNRAA

Format

Online

Language

English

Type

Article

Identifier

https://doi.org/10.1093/mnras/stae2269

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