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

We present 15 high mass X-ray binary (HMXB) candidates in the disk of M31 forwhich we are able to infer compact object type, spectral type of the donorstar, and age using multiwavelength observations from NuSTAR, Chandra, and theHubble Space Telescope (HST). The hard X-ray colors and luminosities fromNuSTAR permit the tentative classification of accreting X-ray binary systems bycompact object type, distinguishing black hole from neutron star systems. Wefind hard state black holes, pulsars, and non-magnetized neutron starsassociated with optical point source counterparts with similar frequency. Wealso find nine non-magnetized neutron stars coincident with globular clustersand an equal number of pulsars with and without point source opticalcounterparts. We perform spectral energy distribution (SED) fitting for themost likely optical counterparts to the HMXB candidates, finding 7 likely highmass stars and 1 possible red Helium burning star. The remaining 7 HMXB opticalcounterparts have poor SED fits, so their companion stars remain unclassified.Using published star formation histories, we find that the majority of HMXBcandidates --- X-ray sources with UV-bright point source optical counterpartcandidates --- are found in regions with star formation bursts less than 50 Myrago, with 3 associated with young stellar ages (<10 Myr). This is consistentwith similar studies of HMXB populations in the Magellanic Clouds, M33, NGC300, and NGC 2403.

Young Accreting Compact Objects in M31: The Combined Power of NuSTAR, Chandra, and Hubble