Conveners
The Black Hole in M87: Block 1
- Brian Punsly (ICRANet)
- Jorge Armando Rueda Hernandez (ICRANet)
Description
The Event Horizon Telescope (EHT) has heightened interest in the black hole in M87. This sessions aims to explore the origin of the annulus of emission at 230 GHz that was detected by EHT. Particular interest is given to non-MHD, low density modelling of the region adjacent to the event horizon. Subjects of primary interest are magnetic reconnection and possible accretion in this limit, as well as jet launching. The high energy emission from this region is an important possibility. The session will also invite discussion of the most recent high resolution images of the jet (at 3mm wavelength).
The Event Horizon Telescope collaboration has released 1.3mm interferometric observations of the core of the galaxy M87. I will review the observations and the general physical principles involved in their interpretation. After describing the basic heuristics needed to understand the effect of a black hole on the observational appearance of nearby emission, I will emphasize that...
The 2017 Event Horizon Telescope (EHT) observations of the core of the galaxy M87 are the first electromagnetic observations probing event horizon scales of a black hole. The data strongly favor an observational appearance dominated by a ring of approximately 40 micro-arcseconds in diameter. However, many interesting questions remain about the appearance of the source. In particular, the...
The first image of the black hole (BH) M87* obtained by the Event Horizon Telescope (EHT) has the shape of a crescent extending from the E to WSW position angles, with a possibly distinct bright hotspot in the ESE sector. We have explored highly simplified toy models for geometric distribution and kinematics of emitting regions in the Kerr metric, assuming that the BH spin vector is fixed to...
Magnetic Reconnection is currently regarded as a rather important process in magnetically dominated regions of galactic and extragalactic sources like the surrounds of black holes and relativistic jets. In this contribution, we discuss briefly the theory of fast magnetic reconnection, especially when driven by turbulence which is very frequent in astrophysical flows, and its implications for...
Spinning black holes have long been suspected to be involved in some of the most extreme astrophysical phenomena such as AGN and their relativistic jets for supermassive black holes, and gamma-ray bursts for stellar-mass black holes. The activity of black holes is often associated with the creation and the launching of a relativistic magnetized plasma jet accompanied by efficient particle...
GRMHD simulations have been very successful in interpreting observations from M87*. However, they are unable to account for several important features, such as the plasma loading of the jet or the details of non-thermal radiation, from first principles. Kinetic simulations, on the other hand, are well suited to the task. In this talk, I will review what we have learned from these kinetic...
Magnetic reconnection in current sheets is conjectured to power bright TeV flares from the black hole in the center of the M87 Galaxy. It is unclear how, where, and when current sheets form in black-hole accretion flows. We show extreme resolution 3D general-relativistic magnetohydrodynamics and 2D general-relativistic particle-in-cell simulations to model reconnection and plasmoid formation...
