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A survey of shipping finance research: setting the future research agenda
Financing shipping related investment projects has always been a focal area of debate and research within the international maritime industry since access to funding can determine the competitiveness of a capital-intensive business as well as its success or failure under adverse market conditions. This paper provides, for the first time, a comprehensive and structured survey of all published research in the area of shipping finance and investment. The review spans approximately four decades (1979-2018) of empirical evidence, including 162 studies published in 48 scholarly journals, complemented with select books and book chapters. The study provides a bibliometric analysis and comprehensive synthesis of existing research offering an invaluable source of information for both the academic community and business practice, shaping the future research agenda in shipping finance and investment
4MOST: Project overview and information for the First Call for Proposals
We introduce the 4-metre Multi-Object Spectroscopic Telescope (4MOST), a new high-multiplex, wide-field spectroscopic survey facility under development for the four-metre-class Visible and Infrared Survey Telescope for Astronomy (VISTA) at Paranal. Its key specifications are: a large field of view (FoV) of 4.2 square degrees and a high multiplex capability, with 1624 fibres feeding two low-resolution spectrographs (), and 812 fibres transferring light to the high-resolution spectrograph (). After a description of the instrument and its expected performance, a short overview is given of its operational scheme and planned 4MOST Consortium science; these aspects are covered in more detail in other articles in this edition of The Messenger. Finally, the processes, schedules, and policies concerning the selection of ESO Community Surveys are presented, commencing with a singular opportunity to submit Letters of Intent for Public Surveys during the first five years of 4MOST operations
White dwarf pollution by hydrated planetary remnants: hydrogen and metals in WDJ204713.76-125908.9
WD J204713.76–125908.9 is a new addition to the small class of white dwarfs with helium-dominated photospheres that
exhibit strong Balmer absorption lines and atmospheric metal pollution. The exceptional abundances of hydrogen observed
in these stars may be the result of accretion of water-rich rocky bodies. We obtained far-ultraviolet and optical spectroscopy
of WD J204713.76–125908.9 using the Cosmic Origin Spectrograph on-board the Hubble Space Telescope and X-shooter on
the Very Large Telescope, and identify photospheric absorption lines of nine metals: C, O, Mg, Si, P, S, Ca, Fe, and Ni. The
abundance ratios are consistent with the steady-state accretion of exo-planetesimal debris rich in the volatile elements carbon
and oxygen, and the transitional element sulphur, by factors of 17, 2, and 4, respectively, compared to the bulk Earth. The
parent body has a composition akin to Solar system carbonaceous chondrites, and the inferred minimum mass, 1.6 × 1020 g, is
comparable to an asteroid 23 km in radius. We model the composition of the disrupted parent body, finding from our simulations
a median water mass fraction of 8 per cent
WD 0141−675: a case study on how to follow-up astrometric planet candidates around white dwarfs
This work combines spectroscopic and photometric data of the polluted white dwarf WD 0141−675, which has a now retracted astrometric super-Jupiter candidate, and investigates the most promising ways to confirm Gaia astrometric planetary candidates and obtain follow-up data. Obtaining precise radial velocity measurements for white dwarfs is challenging due to their intrinsic faint magnitudes, lack of spectral absorption lines, and broad spectral features. However, dedicated radial velocity campaigns are capable of confirming close-in giant exoplanets (a few MJup) around polluted white dwarfs, where additional metal lines aid radial velocity measurements. Infrared emission from these giant exoplanets is shown to be detectable with JWST Mid-Infrared Instrument (MIRI) and will provide constraints on the formation of the planet. Using the initial Gaia astrometric solution for WD 0141−675 as a case study, if there were a planet with a 33.65 d period or less with a nearly edge-on orbit, (1) ground-based radial velocity monitoring limits the mass to <15.4 MJup, and (2) space-based infrared photometry shows a lack of infrared excess and in a cloud-free planetary cooling scenario, a substellar companion would have to be <16 MJup and be older than 3.7 Gyr. These results demonstrate how radial velocities and infrared photometry can probe the mass of the objects producing some of the astrometric signals, and rule out parts of the brown dwarf and planet mass parameter space. Therefore, combining astrometric data with spectroscopic and photometric data is crucial to both confirm and characterize astrometric planet candidates around white dwarfs