HEASA 2026 (29 Sep - 02 Oct)

Session

X-Ray / Gamma-Ray Binaries / Instrumentation

2 Oct 2026, 09:00

Description

Chair: Hartmut Winkler

52. Positron escape from dark matter spikes in black hole X-ray binaries

Mpho Kgoadi (University of the Witwatersrand)

02/10/2026, 09:00

X-Ray and Gamma-Ray Binaries

Contributed Talk

The anomalously fast orbital decay of the black hole X-ray binaries A0620−00 and XTE J1118+480 has been attributed to dynamical friction in dark matter density spikes, and annihilation within these spikes has recently been proposed as the origin of the high-energy positron excess measured by AMS-02. That proposal treats positron propagation using interstellar conditions throughout, neglecting...

37. Super-Eddington accretion and the formation of the massive neutron stars

Dr Lutendo Nyadzani (University of Johannesburg)

02/10/2026, 09:13

X-Ray and Gamma-Ray Binaries

Contributed Talk

Accretion onto the first-born neutron star during a super-Eddington episode has been proposed as one of the formation channels of the most massive neutron stars in the gravitational-wave catalogue, notably the components of GW190425. In this work, we examine the transfer of material from the outer disc to the stellar surface during the super-Eddington phase. We take into account the disc...

58. On the recent multiwavelength results of outbursting Be X-ray binaries

Itumeleng Monageng

02/10/2026, 09:26

X-Ray and Gamma-Ray Binaries

Contributed Talk

Be X-ray binaries, which constitute the largest subclass of high-mass X-ray binary systems, consist of a neutron star in an eccentric orbit around a Be star companion, accompanied by a geometrically thin Keplerian disc. These systems are strong candidates for being progenitors of gravitational waves, as their evolutionary process can ultimately lead to the formation of a binary system...

40. Einstein Probe: Exploring the Dynamic X-ray Universe

David Buckley (South African Astronomical Observatory)

02/10/2026, 09:39

Instrumentation

Contributed Talk

The study of the dynamic Universe is entering a new era of time-domain, multi-wavelength and multi-messenger astronomy. High-energy transients provide unique probes of black-hole accretion, compact objects, stellar explosions and the early Universe, while electromagnetic counterparts to gravitational-wave and neutrino events offer new opportunities for understanding the most energetic cosmic...

66. Assessing the Fringe Detectability of the Africa Millimetre Telescope for Event Horizon Telescope Observations

Hiiko Katjaita (University of Namibia)

02/10/2026, 09:52

Instrumentation

Contributed Talk

The Africa Millimetre Telescope (AMT), planned for construction in Namibia, will expand Africa’s contribution to millimetre very-long-baseline interferometry (VLBI) and the Event Horizon Telescope (EHT), supporting future EHT and multi-wavelength studies of supermassive black holes, accretion flows, and relativistic jets. Its ability to participate effectively in EHT observations will depend...