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/

Zendy Open

Presents the pdf analysis as premium feature

PDF Analysis

Insights

Presents the summarisation as premium feature

Summarisation

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

We have analyzed XMM-Newton observations of the high energy peaked blazar,PKS 2155-304, made on 24 May 2002 in the 0.3 - 10 keV X-ray band. Theseobservations display a mini-flare, a nearly constant flux period and a strongflux increase. We performed a time-resolved spectral study of the data, bydividing the data into eight segments. We fitted the data with a power-law anda broken power-law model, and in some of the segments we found a noticeablespectral flattening of the source's spectrum below 10 keV. We also performedtime-resolved cross-correlation analyses and detected significant hard and softlags (for the first time in a single observation of this source) during thefirst and last parts of the observation, respectively. Our analysis of thespectra, the variations of photon-index with flux as well as the correlationand lags between the harder and softer X-ray bands indicate that both theparticle acceleration and synchrotron cooling processes make an importantcontribution to the emission from this blazar. The hard lags indicate avariable acceleration process. We also estimated the magnetic field value usingthe soft lags. The value of the magnetic field is consistent with the valuesderived from the broad-band SED modeling of this source.

Flux and spectral variability of the blazar PKS 2155-304 with XMM-Newton: Evidence of Particle Acceleration and Synchrotron Cooling