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 report an X-ray study of the evolved Galactic supernova remnant (SNR)G156.2+5.7 based on six pointing observations with Suzaku. The remnant's largeextent (100$\arcmin$ in diameter) allows us to investigate its radial structurein the northwestern and eastern directions from the apparent center. The X-rayspectra were well fit with a two-component non-equilibrium ionization modelrepresenting the swept-up interstellar medium (ISM) and the metal-rich ejecta.We found prominent central concentrations of Si, S and Fe from the ejectacomponent; the lighter elements of O, Ne and Mg were distributed moreuniformly. The temperature of the ISM component suggests a slow shock (610-960km s$^{-1}$), hence the remnant's age is estimated to be 7,000-15,000 yr,assuming its distance to be $\sim$1.1 kpc. G156.2+5.7 has also been thought toemit hard, non-thermal X-rays, despite being considerably older than any othersuch remnant. In response to a recent discovery of a background cluster ofgalaxies (2XMM J045637.2+522411), we carefully excluded its contribution, andreexamined the origin of the hard X-ray emission. We found that the residualhard X-ray emission is consistent with the expected level of the cosmic X-raybackground. Thus, no robust evidence for the non-thermal emission was obtainedfrom G156.2+5.7. These results are consistent with the picture of an evolvedSNR.

A Suzaku Study of Ejecta Structure and Origin of Hard X-ray Emission in the Supernova Remnant G156.2+5.7