English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We have performed phase-resolved spectral analysis of the accreting pulsar1A~0535+262 based on observations of Insight-HXMT during the 2020 Type-IIoutburst of the source. We focus on the two-dimensional dependence of thecyclotron resonance scattering features (CRSFs) along the outburst time and atdifferent phases. The fundamental CRSF line (f-CRSF) shows different time- andphase-dependent behaviors. At higher luminosity, the phase profile of thef-CRSF energy changes from a single peak to double peaks, with the transitionoccurring at MJD 59185. On the contrary, the first harmonic CRSF (1-st CRSF) at$\sim$ 100 keV is only detected within a narrow phase range (0.8$-$1.0)accompanied by a shallow f-CRSF line. Based on these results, we speculate thatwhen the source enters the supercritical regime, the higher accretion columncan significantly enhance the harmonic line at a narrow phase through an"anti-pencil" beam at a higher energy band. At the same time, it will alsoaffect the behavior of the fundamental line.

Phase dependent evolution within large luminosity range of 1A 0535+262 observed by Insight-HXMT during 2020 giant outburst