De Opleidingscommissie

Wellicht heb je term 'opleidingscommissie' (OLC) wel eens gehoord, maar weet je eigenlijk niet wat deze commissie precies doet. Om de OLC meer bekendheid te geven onder studenten volgt een korte toelichting

Thomson scattering in a low-pressure neon mercury positive column

The electron density and the electron temperature in a low-pressure neon mercury positive column are determined using Thomson scattering. Special attention has been given to the stray light reduction in the Thomson scattering setup. The results are obtained in a discharge tube with a 26 mm diam, 10 mbar of neon, a mercury pressure inbetween 0.14 and 0.85 Pa, and an electric current ranging from 100 to 400 mA. The systematic error in the electron density is 15%–45%, the statistical error is 25%–35%. The total error in the electron temperature is 15%–35%. ©2001 American Institute of Physics

Hervorming EU suikerbeleid: gevolgen voor ontwikkelingslanden

Door de in de hervorming van het EU-suikerbeleid voorgestelde prijsverlaging van 33% zullen de exportinkomsten van een aantal ontwikkelingslanden aanzienlijk lager uitvallen. Daling van de Europese productie en van de gesubsidieerde export biedt deze landen echter ook mogelijkheden om hun aandeel op derde markten te vergroten

Commissie BBruut stelt zich voor

Hier stellen de leden van de commissie BBruut zich voor. Komend jaar zullen zij de verantwoording op zich nemen om vier prachtige edities te maken van het semiwetenschappelijke magazine de Bestuurskundige berichten

The low-energy limit of AdS(3)/CFT2 and its TBA

We investigate low-energy string excitations in AdS3 × S3 × T4. When the worldsheet is decompactified, the theory has gapless modes whose spectrum at low energies is determined by massless relativistic integrable S matrices of the type introduced by Al. B. Zamolodchikov. The S matrices are non-trivial only for excitations with identical worldsheet chirality, indicating that the low-energy theory is a CFT2. We construct a Thermodynamic Bethe Ansatz (TBA) for these excitations and show how the massless modes’ wrapping effects may be incorporated into the AdS3 spectral problem. Using the TBA and its associated Y-system, we determine the central charge of the low-energy CFT2 to be c = 6 from calculating the vacuum energy for antiperiodic fermions — with the vacuum energy being zero for periodic fermions in agreement with a supersymmetric theory — and find the energies of some excited states

Lifting asymptotic degeneracies with the Mirror TBA

We describe a qualitative feature of the AdS_5 x S^5 string spectrum which is not captured by the asymptotic Bethe ansatz. This is reflected by an enhanced discrete symmetry in the asymptotic limit, whereby extra energy degeneracy enters the spectrum. We discuss how finite size corrections should lift this degeneracy, through both perturbative (Luscher) and non-perturbative approaches (the Mirror TBA), and illustrate this explicitly on two such asymptotically degenerate states.Comment: v3, 20 pages, 1 figure, 2 tables, as publishe

Excess mortality among essential workers in England and Wales during the COVID-19 pandemic: an updated analysis

BACKGROUND: Excess mortality from all causes combined during the COVID-19 pandemic in England and Wales in 2020 was predominantly higher for essential workers. In 2021, the vaccination programme had begun, new SARS-CoV-2 variants were identified and different policy approaches were used. We have updated our previous analyses of excess mortality in England and Wales to include trends in excess mortality by occupation for 2021. METHODS: We estimated excess mortality for working age adults living in England and Wales by occupational group for each month in 2021 and for the year as a whole. RESULTS: During 2021, excess mortality remained higher for most groups of essential workers than for non-essential workers. It peaked in January 2021 when all-cause mortality was 44.6% higher than expected for all occupational groups combined. Excess mortality was highest for adults working in social care (86.9% higher than expected). CONCLUSION: Previously, we reported excess mortality in 2020, with this paper providing an update to include 2021 data. Excess mortality was predominantly higher for essential workers during 2021. However, unlike the first year of the pandemic, when healthcare workers experienced the highest mortality, the highest excess mortality during 2021 was experienced by social care workers