# Mapping the X-ray Sky with SRG: First Results from eROSITA and ART-XC

Mar 15 – 20, 2020
Garching
Europe/Berlin timezone

## Young accreting binary populations in the pre-eROSITA era

Not scheduled
20m
Garching

Poster

### Speaker

Vallia Antoniou (Texas Tech University and CfA | Harvard & Smithsonian)

### Description

In this talk, I will discuss our current understanding of the formation efficiency of high-mass X-ray binaries (HMXBs) by focusing on results derived from young accreting binary populations in the Magellanic Clouds. Using data from our Chandra X-ray Visionary program, extensive shallow Chandra and XMM-Newton surveys and the literature for the Small and Large Magellanic Cloud (SMC and LMC), respectively, I will present the formation efficiency of HMXBs based on three different indicators: the number ratio of the HMXBs to the (a) total number of OB stars in the same area, (b) the local star-formation rate, and (c) the stellar mass produced during the specific star-formation burst, all as a function of the age of their parent stellar populations. Each of these indicators serves a different role, but in all cases, we find that the HMXB formation efficiency increases as a function of time (following a burst of star formation) up to ∼40-60 Myr, and then gradually decreases. The formation efficiency peaks at ∼30-40 Myr with average rates of ${\rm N(HMXBs)/SFR=339^{+78}_{-83}(M_{\odot}/yr)^{-1}}$, and ${\rm N(HMXB)/M_{\star}=8.74^{+1.0}_{-0.92}M_{\odot}^{-1}}$, in good agreement with previous estimates of the average formation efficiency in the broad ∼20-60 Myr age range. Furthermore, I will compare the formation efficiency of HMXBs in the SMC and the LMC. We have found that the formation efficiency of HMXBs in the LMC is ∼17 times lower than that in the SMC, primarily due to the different ages and metallicity of these X-ray binary populations in the two galaxies (Antoniou et al. 2016, 2019). Finally, I will discuss questions raised by both X-ray binary population studies and studies of individual objects of interest, and prospects for yet further progress from future observations performed by eROSITA.

Presenter status late abstract submission allowed by Andrea Merloni

### Primary author

Vallia Antoniou (Texas Tech University and CfA | Harvard & Smithsonian)

### Co-authors

Dr Andreas Zezas (University of Crete) Dr Jeremy Drake (CfA | Harvard & Smithsonian) Dr Carles Badenes (University of Pittsburgh)

### Presentation materials

There are no materials yet.