Phonon anharmonicities in graphite and graphene

We determine from first-principles the finite-temperature properties--linewidths, line shifts, and lifetimes--of the key vibrational modes that dominate inelastic losses in graphitic materials. In graphite, the phonon linewidth of the Raman-active E2g mode is found to decrease with temperature; such anomalous behavior is driven entirely by electron-phonon interactions, and does not appear in the nearly-degenerate infrared-active E1u mode. In graphene, the phonon anharmonic lifetimes and decay channels of the A'1 mode at K dominate over E2g at G and couple strongly with acoustic phonons, highlighting how ballistic transport in carbon-based interconnects requires careful engineering of phonon decays and thermalization.Comment: 5 pages, 4 figures; typos corrected and reference adde

Search for new physics in Bs→μ+μ−B_s \rightarrow \mu^+ \mu^- and B→K(∗)μ+μ−B \rightarrow K^{(*)} \mu^+ \mu^-

Transitions of the type $b \to s l^+ l^-$ are flavour changing neutral current processes where new physics can enter in competing loop diagrams with respect to the Standard Model contributions. In these decays several observables sensitive to new physics, and where theoretical uncertainties are under control, can be constructed. Particularly interesting are the angular asymmetries in the decay $B_d \to K^* \mu^+ \mu^-$ and the measurement of the branching fraction of the decays $B_{s,d} \to \mu^+ \mu^-$. Recent measurements of these observables and the measurement of the isospin asymmetry in the decays $B \to K^{(*)} \mu^+ \mu^-$ are presented.Comment: Presented at Flavor Physics and CP Violation (FPCP 2012), Hefei, China, May 21-25, 201

What the alligator didn't know: natural selection and love in our mutual friend

This essay reads Our Mutual Friend as Dickens's rejoinder to Darwin's theory of evolution by natural selection, and sees it as a novel that is profoundly shaped by the imaginative impact of Darwin's work. However, the direct influence of On the Origin of Species is not the essay's major concern. Instead, the essay sees this novel as a response to some of the questions posed by Darwin's work about how a natural world driven by chance and contigency, death, waste and hunger might be redeemed. I focus on the figure of Mr Venus, the taxidermist who, I argue, is an affectionate portrait of Dickens's friend Richard Owen. By tracing Owen's involvement in debates over evolution and the origins of life, I show that these contemporary debates had a considerable backwash in a novel saturated with the metaphors of evolution, and centrally concerned with the nature of, and the relationship betweeen, life and death. I suggest that Mr Venus's shop is a comic version of the Hunterian Museum, over which Owen presided, and that its portrayal encapuslates the novel's concerns with evolution, life and death. I argue that Dickens's response to the challenge of Darwinism is to see love as the world's redemption, and that he uses transmuted versions of Mr Venus's shop as a vivid metaphor for the idea that love is the redeeming spark of life. I suggest, though, that in the post-Darwinian imaginative landscape, love could not redeem all, and that Dickens's redeeming vision of love is finally inadequate to save all his characters. 'What the alligator knew, ages deep in the slime' was that love was powerless against nature - and what it didn't know, and Dickens tried to show in this, his last completed novel, is that in spite of the ruthless rapacity of both nature and human society, love makes the world go round

Listen to me : the relationship between an organisation's listening environment and employees' openness to change : a thesis presented in partial fulfilment of the requirements for the degree of Masters of Business Studies (Communication) at Massey University, Wellington, New Zealand

Change is a reality of organisational life. New technologies, globalisation, the vagaries of the economic climate, and internal organisational pressures drive change today faster than ever before. Yet failure rates for change can be up to 70%. Understanding the different drivers of change, and what promotes change success, is therefore critical. Researchers are recognising that change is essentially a human event, and that individuals have a major role in determining whether organisational change will be successful. Employees’ attitudes towards change determine whether they will support or resist it. The focus of this study is on employee’s openness to change, and the extent to which this variable is affected by the listening environment created in the organisation by the supervisor and also that created between team members. An online survey was carried out of 485 employees in one public sector organisation in New Zealand. Measures were taken of employee openness to change, team listening environment, supervisor listening environment and potential demographic contributors. Findings were that the supervisor listening environment had a moderate effect on employees’ openness to change. It also had a similar effect on the team listening environment. However, the team listening environment was found to have only a small little impact on openness to change. Four employee variables— position, tenure, age and gender—were considered, and all were found to influence the relationship between the supervisor listening environment and openness to change. This was especially so for managers, employees between 35 and 54 years of age, and female employees. The impact of employee characteristics on the openness to change variable was also looked at. The only demographic variable that had an impact on openness to change was the position an employee holds in the organisation. The implications of these findings for management is that the quality of the interpersonal relationship between an employee, and their supervisor, as demonstrated by how the supervisor listens to them, creates an environment where employees feel listened to, cared for and connected. This influences an employee’s willingness to support new and different things, that is, their openness to change. This contributes in turn to whether the employee will embrace change or resist it, and ultimately influences whether the organisational change will be successful

Examination of uncertainties in nuclear data for cosmic ray physics with the AMS experiment

High-energy Li-Be-B nuclei in cosmic rays are being measured with unprecedent accuracy by the AMS experiment. These data bring valuable information to the cosmic ray propagation physics. In particular, combined measurements of B/C and Be/B ratios may allow to break the parameter degeneracy between the cosmic-ray diffusion coefficient and the size of the propagation region, which is crucial for dark matter searches. The parameter determination relies in the calculation of the Be and B production from collisions of heavier nuclei with the gas. Using the available cross-section data, I present for the first time an evaluation of the nuclear uncertainties and their impact in constraining the propagation models. I found that the AMS experiment can provide tight constraints on the transport parameters allowing to resolutely break the degeneracy, while nuclear uncertainties in the models are found to be a major limiting factor. Once these uncertainties are accounted, the degeneracy remains poorly resolved. In particular, the Be/B ratio at ~1 - 10 GeV/n is found not to bring valuable information for the parameter extraction. On the other hand, precise Be/B data at higher energy may be useful to test the nuclear physics inputs of the models.Comment: 4 figures, 6 pages, matches published versio