Related papers: FUors, EXors and the role of intermediate objects
Context. Episodic accretion in young stellar objects (YSOs) is thought to play a critical role in addressing the "luminosity problem" associated with star formation. However, optical surveys tend to bias against sources that are heavily…
Context. In August 2010, the sudden optical brightening of two young stellar objects, located in the North America/Pelican Nebula Complex, was announced. Early observations indicated that these objects may belong to the FUor or EXor class…
Improving our understanding of the initial conditions and earliest stages of protostellar collapse is crucial to gain insight into the origin of stellar masses, multiple systems, and protoplanetary disks. Observationally, there are two…
In the present paper we discuss a selection of facts and questions related to observations and evolutionary calculations of massive single stars and massive stars in interacting binaries. We focus on the surface chemical abundances, the…
The first stages of planet formation usually occur when the host star is still in a (relatively) dense star-forming region, where the effects of the external environment may be important for understanding the outcome of the planet formation…
Disks are ubiquitous in stellar astronomy, and play a crucial role in the formation and evolution of stars. In this contribution we present an overview of the most recent results, with emphasis on high spatial and spectral resolution. We…
The initial conditions, physics, and outcome of planet formation are now constrained by detailed observations of protoplanetary disks, laboratory experiments, and the discovery of thousands of extrasolar planetary systems. These…
We present the results of a comparison between classical and newly identified EXor based on literature data and aimed at recognizing possible differences or similarities of both categories. Optical and near-IR two-color diagrams, modalities…
We summarize recent significant progress in the development of a first-principles formalism to describe the formation and evolution of matter in very high energy heavy ion collisions. The key role of quantum fluctuations both before and…
Optical and infrared surveys have detected increasing numbers of disc accretion outbursts in young stars. Some models of these FU Ori-type events predict that the outburst should start at near- to mid-infrared wavelengths before an optical…
This prospective chapter gives our view on the evolution of the study of circumstellar discs within the next 20 years from both observational and theoretical sides. We first present the expected improvements in our knowledge of…
In this paper, I present and discuss some recent observational results which may have important implications for our understanding of late phases of binary evolution.
Newly formed stars are often observed to possess circumstellar disks, from which mass continues to be accreted onto the star and fed into outflowing jets, and which eventually may evolve into dusty debris disks and planetary systems. Recent…
Long-lasting episodes of high accretion can strongly impact stellar and planetary formation. However, the universality of these events during the formation of young stellar objects (YSOs) is still under debate. Accurate statistics of strong…
Extremely Red Objects (EROs) provide the important possibility to shed light on the formation and evolution of the present-day massive ellipticals. On one hand, they allow to select z>1 old passively evolving spheroidals and to compare…
We present a pedagogic discussion on the role of novel phases of dense baryonic matter in ``neutron'' stars. Qualitative aspects of the physics that drives phase transitions and some of its astrophysical consequences are discussed.…
Using recent data from photometric monitoring and data from the photographic plate archives we aim to study, the long-term photometric behavior of FUors. The construction of the historical light curves of FUors could be very important for…
We highlight recent theoretical and observational progress in several areas of neutron star astrophysics, and discuss the prospect for advances in the next decade.
Comets, asteroids and moons that orbit stars and planets exterior to our solar system are prefixed with "exo". While the existence of these objects is certain, our understanding of their physical properties, composition, and diversity is…
Since the 1990's, protoplanetary disks and planetary disks have been intensively observed from the optical to the millimetre wavelength and many models have been developed to investigate their gas and dust properties and dynamics. These…