Temperature Measurement during Thermonuclear X-ray Bursts with BeppoSAX

TL;DR

This study measures temperature evolution during thermonuclear X-ray bursts in low-mass X-ray binaries using BeppoSAX data, employing a novel ratio method to determine temperature without traditional spectroscopy.

Contribution

Introduces a new technique to estimate burst temperatures from count rate ratios, bypassing standard time-resolved spectroscopy methods.

Findings

Temperatures up to ~3.0 keV were observed without photospheric radius expansion.

High temperatures occurred across different spectral states.

Analysis included 22 bursts from six sources.

Abstract

We have carried out a study of temperature evolution during thermonuclear bursts in LMXBs using broad band data from two instruments onboard BeppoSAX, the MECS and the PDS. However, instead of applying the standard technique of time resolved spectroscopy, we have determined the temperature in small time intervals using the ratio of count rates in the two instruments assuming a blackbody nature of burst emission and different interstellar absorption for different sources. Data from a total of twelve observations of six sources were analysed during which 22 bursts were detected. We have obtained temperatures as high as ~3.0 keV, even when there is no evidence of photospheric radius expansion. These high temperatures were observed in the sources within different broadband spectral states (soft and hard).