The stellar halo of the Galaxy

Stellar halos may hold some of the best preserved fossils of the formation history of galaxies. They are a natural product of the merging processes that probably take place during the assembly of a galaxy, and hence may well be the most ubiquitous component of galaxies, independently of their Hubble type. This review focuses on our current understanding of the spatial structure, the kinematics and chemistry of halo stars in the Milky Way. In recent years, we have experienced a change in paradigm thanks to the discovery of large amounts of substructure, especially in the outer halo. I discuss the implications of the currently available observational constraints and fold them into several possible formation scenarios. Unraveling the formation of the Galactic halo will be possible in the near future through a combination of large wide field photometric and spectroscopic surveys, and especially in the era of Gaia.Comment: 46 pages, 16 figures. References updated and some minor changes. Full-resolution version available at http://www.astro.rug.nl/~ahelmi/stellar-halo-review.pd

A review of elliptical and disc galaxy structure, and modern scaling laws

A century ago, in 1911 and 1913, Plummer and then Reynolds introduced their models to describe the radial distribution of stars in `nebulae'. This article reviews the progress since then, providing both an historical perspective and a contemporary review of the stellar structure of bulges, discs and elliptical galaxies. The quantification of galaxy nuclei, such as central mass deficits and excess nuclear light, plus the structure of dark matter halos and cD galaxy envelopes, are discussed. Issues pertaining to spiral galaxies including dust, bulge-to-disc ratios, bulgeless galaxies, bars and the identification of pseudobulges are also reviewed. An array of modern scaling relations involving sizes, luminosities, surface brightnesses and stellar concentrations are presented, many of which are shown to be curved. These 'redshift zero' relations not only quantify the behavior and nature of galaxies in the Universe today, but are the modern benchmark for evolutionary studies of galaxies, whether based on observations, N-body-simulations or semi-analytical modelling. For example, it is shown that some of the recently discovered compact elliptical galaxies at 1.5 < z < 2.5 may be the bulges of modern disc galaxies.Comment: Condensed version (due to Contract) of an invited review article to appear in "Planets, Stars and Stellar Systems"(www.springer.com/astronomy/book/978-90-481-8818-5). 500+ references incl. many somewhat forgotten, pioneer papers. Original submission to Springer: 07-June-201

Low socioeconomic status is an under-recognised source of challenges in academia

Barriers faced by underrepresented groups in academia have increasingly formed the basis of serious discussion, consideration, and policies, recently (in the UK) under the mantle of equality, diversity, and inclusivity (EDI). While such recognition has not solved the challenges encountered by, for instance, women and ethnic minorities, it has at least ensured that consideration of such issues is becoming a normal part of policy and practice. One underrepresented group in academia is low socioeconomic status (working class) backgrounds, a characteristic that intersects widely with other more commonly considered EDI groups. However, socioeconomic status is not a legally protected characteristic in the UK, which has resulted in it receiving less attention in terms of consideration of the barriers it imposes and possible mitigations needed. Moreover, unlike often more salient EDI characteristics such as gender and ethnicity, outward-facing cues of socioeconomic status are less visible at a glance, although they are often detectable in more subtle or indirect ways. Coupled with the attempts many working-class academics make to ‘mask’ cues of their background, this creates a situation whereby low socioeconomic status is a ‘hidden’ barrier that commonly remains unrecognised and unaddressed throughout much of academia. Here, we provide an overview of the challenges faced by working-class academic scientists based partly on the literature, which is currently limited, and partly from the experiences of our diverse working-class authorship team. In doing so, we hope to bring greater awareness of working-class backgrounds to the table in EDI discussions, and we provide suggestions for future research on and mitigation of the challenges faced by academic scientists from low socioeconomic status backgrounds

Low socioeconomic status is an under‐recognised source of challenges in academia

AbstractBarriers faced by underrepresented groups in academia have increasingly formed the basis of serious discussion, consideration, and policies, recently (in the UK) under the mantle of equality, diversity, and inclusivity (EDI). While such recognition has not solved the challenges encountered by, for instance, women and ethnic minorities, it has at least ensured that consideration of such issues is becoming a normal part of policy and practice. One underrepresented group in academia is low socioeconomic status (working class) backgrounds, a characteristic that intersects widely with other more commonly considered EDI groups. However, socioeconomic status is not a legally protected characteristic in the UK, which has resulted in it receiving less attention in terms of consideration of the barriers it imposes and possible mitigations needed. Moreover, unlike often more salient EDI characteristics such as gender and ethnicity, outward‐facing cues of socioeconomic status are less visible at a glance, although they are often detectable in more subtle or indirect ways. Coupled with the attempts many working‐class academics make to ‘mask’ cues of their background, this creates a situation whereby low socioeconomic status is a ‘hidden’ barrier that commonly remains unrecognised and unaddressed throughout much of academia. Here, we provide an overview of the challenges faced by working‐class academic scientists based partly on the literature, which is currently limited, and partly from the experiences of our diverse working‐class authorship team. In doing so, we hope to bring greater awareness of working‐class backgrounds to the table in EDI discussions, and we provide suggestions for future research on and mitigation of the challenges faced by academic scientists from low socioeconomic status backgrounds.</jats:p