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 Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The X-ray source RX J004717.4-251811 in the nearby starburst galaxy NGC 253was found to undergo changes from a low to a high state twice, during anXMM-Newton EPIC observation in December 2000 and also during a Chandraobservation one year earlier. These transitions are interpreted as egressesfrom eclipses of a compact object in a high mass X-ray binary system (HMXB).The phase of eclipse egress during the Chandra observation is given bybarycenter corrected MJD 51539.276+-0.006 and the binary period determined to p= (352.870+-0.012) d / n by the time difference between the two egresses andnumber n of periods in-between. Allowed periods may be further constrained byadditional XMM-Newton, Chandra, ROSAT, and Einstein observations resulting inonly seven acceptable periods with 1.47024 d and 3.20793 d most promising. Nosignificant regular pulsations of the source in the range 0.3-1000 s werefound. Fluctuations on time scales of 1000 s were observed together withextended intervals of low intensity. The energy spectrum during the brightstate can best be described by an absorbed flat power law (NH=1.9x10^21 cm^-2,Gamma=1.7). In the bright state the source luminosity is 4x10^38 erg/s (0.5--5keV), just compatible with the Eddington luminosity of a 1.4 M_sun neutronstar. A possible optical identification is suggested. RX J004717.4-251811parameters are compared to other eclipsing X-ray binaries (XRBs).Comment: 9 pages including 5 figures, accepted for publication in A&

RX J004717.4-251811: The first eclipsing X-ray binary outside the Local Group