Year: 2017
Type: article
Abstract: The mergers of double neutron star (NS–NS) and black hole (BH)–NS binaries are promising gravitational wave (GW) sources for Advanced LIGO and future GW detectors. The neutron-rich ejecta from such merger events undergoes rapid neutron capture ( r -process) nucleosynthesis, enriching our Galaxy with rare heavy elements like gold and platinum. The radioactive decay of these unstable nuclei also powers a rapidly evolving, supernova-like transient known as a “kilonova” (also known as “macronova”). Kilonovae are an approximately isotropic electromagnetic counterpart to the GW signal, which also provides a unique and direct probe of an important, if not dominant, r -process site. I review the history and physics of kilonovae, leading to the current paradigm of week-long emission with a spectral peak at near-infrared wavelengths. Using a simple light curve model to illustrate the basic physics, I introduce potentially important variations on this canonical picture, including: $$\sim $$ ∼ day-long optical (“blue”) emission from lanthanide-free components of the ejecta; $$\sim $$ ∼ hour-long precursor UV/blue emission, powered by the decay of free neutrons in the outermost ejecta layers; and enhanced emission due to energy input from a long-lived central engine, such as an accreting BH or millisecond magnetar. I assess the prospects of kilonova detection following future GW detections of NS–NS/BH–NS mergers in light of the recent follow-up campaign of the LIGO binary BH–BH mergers.
Source: Living Reviews in Relativity
Author: Brian D. Metzger
Institution: Columbia University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
Awards: JINA Center for the Evolution of the Elements, PARTICLE ACCELERATION AND NON-THERMAL EMISSION IN GAMMA-RAY NOVAE THE DISCOVERY BY FERMI LAT OF GEV GAMMA-RAYS FROM CLASSICAL NOVAE ILLUSTRATES THAT, G2054975126, Signatures of Shocks and Particle Acceleration from Novae in our Galaxy, NUCLEAR REACTIONS PLAY A KEY ROLE IN THE ACCRETION DISKS AND OUTFLOWS ASSOCIATED WITH THE MERGER OF BINARY COMPACT OBJECTS AND THE CENTRAL ENGINES OF, G425872791, G540681716, G5868511136, G5974216233, Testing the Millisecond Magnetar Model for Gamma-Ray Bursts and Superluminous Supernovae, G7240239236, THE DISCOVERY BY FERMI LAT OF GEV GAMMA-RAYS FROM CLASSICAL NOVAE ILLUSTRATES THAT SHOCKS AND HIGH ENERGY PARTICLE ACCELERATION ARE COMMON IN NOVA OUTFLOWS. A MODEL WILL BE FURTHER DEVELOPED FOR THE MULTI-WAVELENGTH THERMAL AND NON-THERMAL EMISSION OF NOVA SHOCKS THAT INCLUDES FOR THE FIRST TIME EFFECTS SUCH AS RADIATIVE COOLING OF THE SHOCKED GAS A SELF-CONSISTENT TREATMENT OF THE IONIZATION OF THE UNSHOCKED MEDIUM AND THE EFFECTS OF RELATIVISTIC PARTICLES AND MAGNETIC FIELDS ON THE COMPRESSIBILITY AND EMISSION OF THE POST SHOCK GAS. FERMI DETECTIONS OF NOVAE WILL BE USED IN COMBINATION WITH GAMMA- RAY OPTICAL AND RADIO DATA TO CONSTRAIN THE EFFICIENCY AND SPECTRUM OF NON-THERMAL PARTICLE ACCELERATION AND MAGNETIC FIELD AMPLIFICATION IN NON-RELATIVISTIC SHOCKS., G868755391
OpenAlex ID: W4211256362