Herbig Stars: A Quarter Century of Progress

TL;DR

This paper reviews 25 years of research on Herbig Ae/Be stars, highlighting advances in understanding their properties, disks, accretion processes, and potential for planet formation, and proposes a new definition.

Contribution

It provides a comprehensive update on Herbig Ae/Be stars since 1998, including new insights into their disks, accretion, and planet formation evidence.

Findings

Enhanced understanding of circumstellar disk properties

Evidence for planet formation in Herbig star disks

Refined criteria for classifying Herbig Ae/Be stars

Abstract

Herbig Ae/Be stars are young contracting stars on the radiative track in the HR diagram on their way to the main sequence. These stars provide a valuable link between high and low mass stars. Here we review the progress that has been made in our understanding of these fascinating objects and their disks since the last major review on this topic published in 1998. We begin with a general overview of these stars and their properties. We then discuss the accretion of circumstellar material onto these stars. Next we discuss the dust and gas properties of the circumstellar disk before exploring the evidence for planet formation in these disks. We conclude with a brief discussion of future prospects for deepening our understanding of these sources and propose a new working definition of Herbig Ae/Be stars.