Transcendence over Diversity: black women in the academy

Universities, like many major public institutions have embraced the notion of ‘diversity’ virtually uncritically- it is seen as a moral ‘good in itself’. But what happens to those who come to represent ‘diversity’- the black and minority ethnic groups targeted to increase the institutions thirst for global markets and aversion to accusations of institutional racism? Drawing on existing literature which analyses the process of marginalization in higher education, this paper explores the individual costs to black and female academic staff regardless of the discourse on diversity. However despite the exclusion of staff, black and minority ethnic women are also entering higher education in relatively large numbers as students. Such ‘grassroots’ educational urgency transcends the dominant discourse on diversity and challenges presumptions inherent in top down initiatives such as ‘widening participation’. Such a collective movement from the bottom up shows the importance of understanding black female agency when unpacking the complex dynamics of gendered and racialised exclusion. Black women’s desire for education and learning makes possible a reclaiming of higher education from creeping instrumentalism and reinstates it as a radical site of resistance and refutation

Bathyal demersal fishes of the Charlie-Gibbs Fracture Zone region (49°–54°N) of the Mid-Atlantic Ridge : III. Results from remotely operated vehicle (ROV) video transects

Peer reviewedPublisher PD

MeV Tau Neutrino in Gauge Mediated Supersymmetry Breaking Model

A supersymmetric model which naturally accommodates MeV tau neutrino within the framework of gauge mediated supersymmetry breaking is described. The lepton number violation is originally introduced in the messenger sector of the theory. A large slepton-Higgs mixing mass and a small lepton-higgsino mixing mass are generated at one-loop. Scalar tau neutrino has non-vanishing vacuum expectation value. These result in a non-zero \nu_{\tau} mass which is in the range of (1-10) MeV.Comment: 18 pages, latex, two figure

Links between deep-sea respiration and community dynamics

It has been challenging to establish the mechanisms that link ecosystem functioning to environmental and resource variation, as well as community structure, composition and compensatory dynamics. A compelling hypothesis of compensatory dynamics, known as 'zero-sum' dynamics, is framed in terms of energy resource and demand units, where there is an inverse link between the number of individuals in a community and the mean individual metabolic rate. However, body-size energy distributions that are non-uniform suggest a niche advantage at a particular size class, which suggests a limit to which metabolism can explain community structuring. Since 1989, the composition and structure of abyssal seafloor communities in the northeast Pacific and northeast Atlantic have varied inter-annually with links to climate and resource variation. Here, for the first time, class and mass-specific individual respiration rates were examined along with resource supply and time series of density and biomass data of the dominant abyssal megafauna, echinoderms. Both sites had inverse relationships between density and mean individual metabolic rate. We found fourfold variation in echinoderm respiration over inter-annual timescales at both sites, which were linked to shifts in species composition and structure. In the north-eastern Pacific, the respiration of mobile surface deposit feeding echinoderms was positively linked to climate-driven particulate organic carbon fluxes with a temporal lag of about one year, respiring about 1-6% of the annual particulate organic carbon flux

Tunneling of quantum rotobreathers

We analyze the quantum properties of a system consisting of two nonlinearly coupled pendula. This non-integrable system exhibits two different symmetries: a permutational symmetry (permutation of the pendula) and another one related to the reversal of the total momentum of the system. Each of these symmetries is responsible for the existence of two kinds of quasi-degenerated states. At sufficiently high energy, pairs of symmetry-related states glue together to form quadruplets. We show that, starting from the anti-continuous limit, particular quadruplets allow us to construct quantum states whose properties are very similar to those of classical rotobreathers. By diagonalizing numerically the quantum Hamiltonian, we investigate their properties and show that such states are able to store the main part of the total energy on one of the pendula. Contrary to the classical situation, the coupling between pendula necessarily introduces a periodic exchange of energy between them with a frequency which is proportional to the energy splitting between quasi-degenerated states related to the permutation symmetry. This splitting may remain very small as the coupling strength increases and is a decreasing function of the pair energy. The energy may be therefore stored in one pendulum during a time period very long as compared to the inverse of the internal rotobreather frequency.Comment: 20 pages, 11 figures, REVTeX4 styl

Lepton Flavour Violating Leptonic/Semileptonic Decays of Charged Leptons in the Minimal Supersymmetric Standard Model

We consider the leptonic and semileptonic (SL) lepton flavour violating (LFV) decays of the charged leptons in the minimal supersymmetric standard model (MSSM). The formalism for evaluation of branching fractions for the SL LFV charged-lepton decays with one or two pseudoscalar mesons, or one vector meson in the final state, is given. Previous amplitudes for the SL LFV charged-lepton decays in MSSM are improved, for instance the $\gamma$-penguin amplitude is corrected to assure the gauge invariance. The decays are studied not only in the model-independent formulation of the theory in the frame of MSSM, but also within the frame of the minimal supersymmetric SO(10) model within which the parameters of the MSSM are determined. The latter model gives predictions for the neutrino-Dirac Yukawa coupling matrix, once free parameters in the model are appropriately fixed to accommodate the recent neutrino oscillation data. Using this unambiguous neutrino-Dirac Yukawa couplings, we calculate the LFV leptonic and SL decay processes assuming the minimal supergravity scenario. A very detailed numerical analysis is done to constrain the MSSM parameters. Numerical results for SL LFV processes are given, for instance for tau -> e (mu) pi0, tau -> e (mu) eta, tau -> e (mu) eta', tau -> e (mu) rho0, tau -> e (mu) phi, tau -> e (mu) omega, etc.Comment: 36 pages, 3 tables, 5 .eps figure

Muon Track Reconstruction and Data Selection Techniques in AMANDA

The Antarctic Muon And Neutrino Detector Array (AMANDA) is a high-energy neutrino telescope operating at the geographic South Pole. It is a lattice of photo-multiplier tubes buried deep in the polar ice between 1500m and 2000m. The primary goal of this detector is to discover astrophysical sources of high energy neutrinos. A high-energy muon neutrino coming through the earth from the Northern Hemisphere can be identified by the secondary muon moving upward through the detector. The muon tracks are reconstructed with a maximum likelihood method. It models the arrival times and amplitudes of Cherenkov photons registered by the photo-multipliers. This paper describes the different methods of reconstruction, which have been successfully implemented within AMANDA. Strategies for optimizing the reconstruction performance and rejecting background are presented. For a typical analysis procedure the direction of tracks are reconstructed with about 2 degree accuracy.Comment: 40 pages, 16 Postscript figures, uses elsart.st

Results from the Antarctic Muon and Neutrino Detector Array (AMANDA)

We show new results from both the older and newer incarnations of AMANDA (AMANDA-B10 and AMANDA-II, respectively). These results demonstrate that AMANDA is a functioning, multipurpose detector with significant physics and astrophysics reach. They include a new higher-statistics measurement of the atmospheric muon neutrino flux and preliminary results from searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, gamma-ray bursters and diffuse sources producing muons in the detector, and diffuse sources producing electromagnetic or hadronic showers in or near the detector.Comment: Invited talk at the XXth International Conference on Neutrino Physics and Astrophysics (Neutrino 2002), Munich, Germany, May 25-30, 200