European ALMA operations: the interaction with and support to the users

The Atacama Large Millimetre/submillimetre Array (ALMA) is one of the largest and most complicated observatories ever built. Constructing and operating an observatory at high altitude (5000m) in a cost effective and safe manner, with minimal effect on the environment creates interesting challenges. Since the array will have to adapt quickly to prevailing weather conditions, ALMA will be operated exclusively in service mode. By the time of full science operations, the fundamental ALMA data product shall be calibrated, deconvolved data cubes and images, but raw data and data reduction software will be made available to users as well. User support is provided by the ALMA Regional Centres (ARCs) located in Europe, North America and Japan. These ARCs constitute the interface between the user community and the ALMA observatory in Chile. For European users the European ARC is being set up as a cluster of nodes located throughout Europe, with the main centre at the ESO Headquarters in Garching. The main centre serves as the access portal and in synergy with the distributed network of ARC nodes, the main aim of the ARC is to optimize the ALMA science output and to fully exploit this unique and powerful facility. The aim of this article is to introduce the process of proposing for observing time, subsequent execution of the observations, obtaining and processing of the data in the ALMA epoch. The complete end-to-end process of the ALMA data flow from the proposal submission to the data delivery is described.Comment: 7 pages, three figure

Making Sense of EU State-aid Requirements; The case of Green Services

This article describes the establishment of a new local governance arrangement called `Green Service¿ in the Netherlands. Under this programme, farmers are financially rewarded - by both public and private bodies - for their nature and landscape management and development activities. Despite a general positive stance, it has taken considerable efforts and time for these programmes to take off, in particular due to uncertainties and discussions on whether these activities would be feasible under the EU state aid regime. The multi level setting in which these rules had to be complied with contributed much to the long lasting discussion on how to interpret these rules and threatened the credibility of this new governance arrangement. We will describe and explain this process by using a so-called `processual institutional¿ approach and more specifically by drawing on the socio-cognitive literature on conflict escalation (Pruitt and Rubin 1986; Rubin, Pruitt et al. 1994)

Hydrogen 21-Centimeter Emission from a Galaxy at Cosmological Distance

We have detected the neutral atomic hydrogen (HI) emission line at a cosmologically significant distance (z=0.18) in the rich galaxy cluster Abell 2218 with the Westerbork Synthesis Radio Telescope. The HI emission originates in a spiral galaxy 2.0 megaparsecs from the cluster core. No other significant detections have been made in the cluster, suggesting that the mechanisms that remove neutral gas from cluster galaxies are efficient. We infer that fewer than three gas-rich galaxies were accreted by Abell 2218 over the past 10^9 years. This low accretion rate is qualitatively consistent with low-density cosmological models in which clusters are largely assembled at z>1.Comment: 7 pages, 2 figures. Science 2001 September 7; 293, 1800 (in reports). Also available from http://www.sciencemag.org/cgi/content/abstract/293/5536/180

International students' loneliness, depression and stress levels in COVID-19 crisis. The role of social media and the host university

The move to university life is characterized by strong emotions, some of them negative, such as loneliness, anxiety, and depression. These negative emotions are strengthened due to the obligatory lockdown due to the COVID-19 pandemic. Previous research indicates association among the use of social media, university satisfaction, and the aforementioned emotions. We report findings from 248 international undergraduates in The Netherlands, all students at the International School of Business. Our results indicate strong correlations between anxiety, loneliness, and COVID-19-related stress with university satisfaction together with social capital. Keywords: COVID-19; Pandemic; lockdown; loneliness; depression; anxiety; international studentsComment: 14 page

An HI survey of the Centaurus and Sculptor Groups - Constraints on the space density of low mass galaxies

We present results of two 21-cm HI surveys performed with the Australia Telescope Compact Array in the nearby Centaurus A and Sculptor galaxy groups. These surveys are sensitive to compact HI clouds and galaxies with HI masses as low as 3E+06 Msun, and are therefore among the most sensitive extragalactic HI surveys to date. The surveys consist of sparsely spaced pointings that sample approximately 2% of the groups' area on the sky. We detected previously known group members, but we found no new HI clouds or galaxies down to the sensitivity limit of the surveys. If the HI mass function had a faint end slope of alpha = 1.5 below M_{HI} = 10^{7.5} Msun in these groups, we would have expected ~3 new objects. Cold dark matter theories of galaxy formation predict the existence of a large number low mass DM sub-halos that might appear as tiny satellites in galaxy groups. Our results support and extend similar conclusions derived from previous HI surveys that a HI rich population of these satellites does not exist.Comment: Accepted for publication in A&

The Luminosity Function and Surface Brightness Distribution of HI Selected Galaxies

We measure the z=0 B-band optical luminosity function (LF) for galaxies selected in a blind HI survey. The total LF of the HI selected sample is flat, with Schechter parameters M*=-19.38_{-0.62}^{+1.02} + 5 log h mag and alpha=-1.03_{-0.15}^{+0.25}, in good agreement with LFs of optically selected late-type galaxies. Bivariate distribution functions of several galaxy parameters show that the HI density in the local Universe is more widely spread over galaxies of different size, central surface brightness, and luminosity than is the optical luminosity density. The number density of very low surface brightness (>24.0 mag/arcsec^2) gas-rich galaxies is considerably lower than that found in optical surveys designed to detect dim galaxies. This suggests that only a part of the population of LSB galaxies is gas rich and that the rest must be gas poor. However, we show that this gas-poor population must be cosmologically insignificant in baryon content. The contribution of gas-rich LSB galaxies (>23.0 mag/arcsec^2) to the local cosmological gas and luminosity density is modest (18_{-5}^{+6} and 5_{-2}^{+2} per cent respectively); their contribution to Omega_matter is not well-determined, but probably < 11 per cent. These values are in excellent agreement with the low redshift results from the Hubble Deep Field.Comment: Accepted for publication in MNRAS, 12 pages 6 figure

Nuclear versus Coal plus CCS: A Comparison of Two Competitive Base-load Climate Control Options

In this paper we analyze the relative importance and mutual behavior of two competing base-load electricity generation options that each are capable of contributing significantly to the abatement of global CO2 emissions: nuclear energy and coal-based power production complemented with CO2 capture and storage (CCS). We also investigate how, in scenarios from an integrated assessment model that simulates the economics of a climate-constrained world, the prospects for nuclear energy would change if exogenous limitations on the spread of nuclear technology were relaxed. Using the climate change economics model WITCH we find that until 2050 the resulting growth rates of nuclear electricity generation capacity become comparable to historical rates observed during the 1980s. Given that nuclear energy continues to face serious challenges and contention, we inspect how extensive the improvements of coal-based power equipped with CCS technology would need to be if our model is to significantly scale down the construction of new nuclear power plants.Economic Competition, Electricity Sector, Nuclear Power, Coal Power, CCS, Renewables, Climate Policy

Environmental Externalities of Geological Carbon Sequestration Effects on Energy Scenarios

Geological carbon sequestration seems one of the promising options to address, in the near term, the global problem of climate change, since carbon sequestration technologies are in principle available today and their costs are expected to be affordable. Whereas extensive technological and economic feasibility studies rightly point out the large potential of this ‘clean fossil fuel’ option, relatively little attention has been paid so far to the detrimental environmental externalities that the sequestering of CO2 underground could entail. This paper assesses what the relevance might be of including these external effects in long-term energy planning and scenario analyses. Our main conclusion is that, while these effects are generally likely to be relatively small, carbon sequestration externalities do matter and influence the nature of future world energy supply and consumption. More importantly, since geological carbon storage (depending on the method employed) may in some cases have substantial external impacts, in terms of both environmental damage and health risks, it is recommended that extensive studies are performed to quantify these effects. This article addresses three main questions: (i) What may energy supply look like if one accounts for large-scale CO2 sequestration in the construction of long-term energy and climate change scenarios; (ii) Suppose one hypothesizes a quantification of the external environmental costs of CO2 sequestration, how do then these supposed costs affect the evolution of the energy system during the 21st century; (iii) Does it matter for these scenarios whether carbon sequestration damage costs are charged directly to consumers or, instead, to electricity producers?Geological carbon storage, External costs, Energy scenarios

Climate Uncertainty and the Necessity to Transform Global Energy Supply

This paper analyses the policy relevance of the dominant uncertainties in our current scientific understanding of the terrestrial climate system, and provides further evidence for the need to radically transform - this century - our global infrastructure of energy supply, given the global average temperature increase as a result of anthropogenic carbon dioxide emissions. We investigate the effect on required CO2 emission reduction efforts, both in terms of how much and when, of our uncertain knowledge today of the climate sensitivity to a doubling in them atmospheric CO2 concentration. Also the roles of carbon-free energy and energy savings, and their evolutions over time, are researched, as well as their dependence on some of our characteristic modelling features. We use a top-down model in which there are two competing energy sources, fossil and non-fossil. Technological change is represented endogenously through learning curves, and modest but non-zero demand exists for the relatively expensive carbon-free energy resource.Global warming, CO2 emissions, Climate sensitivity, Fossil to non-fossil transition, Carbon-free power, Energy savings