The Right to Be Cold: One Woman’s Fight to Protect the Arctic and Save the Planet from Climate Change by Sheila Watt-Cloutier

Review of Sheila Watt-Cloutier\u27s The Right to Be Cold: One Woman\u27s Fight to Protect the Arctic and Save the Planet from Climate Change

Explosions of LBV and Post-LBV Stars

In this contributed talk I presented the observational evidence for supernova (SN) explosions of stars in the luminous blue variable (LBV) and the immediate post-LBV evolutionary phases. We now have compelling indications that two recent SNe of Type II-“narrow” (IIn) were the explosions of LBVs, including the direct identification of the progenitor LBV for one of these examples. A recent SN of Type Ic exploded as a helium star, two years after the powerful LBV outburst of its progenitor. These cases were also discussed by other presenters at this Workshop in some detail. I instead focus more on another example, SN2001em, which was first identified as a Type Ib/c, but later evolved to Type IIn. I argue that the progenitor of this SN exploded as a Wolf- Rayet (WR) star, following an eruptive LBV phase. Furthermore, I suggest that two “SN impostors,” i.e., extragalactic massive stars observed to undergo pre-SN LBV eruptions (similar to η Carinae), may well have evolved to the WR phase in real time

Tailoring e-commerce sites to ease recovery after disruptions

Developers of e-commerce applications are often unrealistic about how their Web site is going to be used, and about possible outcomes during site usage. The most commonly considered outcomes of a user's visit to a site are firstly that the visit culminates in a sale, and secondly that the user leaves the site without buying anything - perhaps to return later. In the second case, sites often "remember" any accumulated items so that a shopper can return at a later stage to resume shopping. In this paper, we consider certain disruptions, such as breakdowns, problems caused by human errors and interruptions, which could affect the outcome of the e-commerce shopping experience. These events have definite and possibly long-lasting effects on users, and applications should therefore be developed to cater for these eventualities so as to enhance the usability of the site and encourage further usage. We develop a model for analysing e-commerce application usage and, using this model, propose an evaluation strategy for determining whether an e-commerce site is resistant to such factors. The proposed evaluation mechanism is applied to three sites to arrive at what we call a "disruption-resistance score"

Using Λb→Λμ+μ−\Lambda_b\to \Lambda\mu^+\mu^- data within a Bayesian analysis of ∣ΔB∣=∣ΔS∣=1|\Delta B| = |\Delta S| = 1 decays

We study the impact of including the baryonic decay $\Lambda_b\to \Lambda(\to p \pi^-)\mu^+\mu^-$ in a Bayesian analysis of $|\Delta B | = |\Delta S| = 1$ transitions. We perform fits of the Wilson coefficients $C_{9}$, $C_{9'}$, $C_{10}$ and $C_{10'}$, in addition to the relevant nuisance parameters. Our analysis combines data for the differential branching fraction and three angular observables of $\Lambda_b\to \Lambda(\to p \pi^-)\mu^+\mu^-$ with data for the branching ratios of $B_s \to \mu^+\mu^-$ and inclusive $b \to s\ell^+\ell^-$ decays. Newly available precise lattice QCD results for the full set of $\Lambda_b \to \Lambda$ form factors are used to evaluate the observables of the baryonic decay. Our fits prefer shifts to $C_{9}$ that are opposite in sign compared to those found in global fits of only mesonic decays, and the posterior odds show no evidence of physics beyond the Standard Model. We investigate a possible hadronic origin of the observed tensions between theory and experiment.Comment: 9 pages, 2 figures; v2 as published: added some clarifications, changed setup for model comparisons, expanded conclusion

Zero-Recoil Sum Rules for Λb→Λc\Lambda_b \to \Lambda_c Form Factors

We set up a zero recoil sum rule to constrain the form factors of the $\Lambda_b \to \Lambda_c$ transition. Our results are compared with the recent lattice calculation for these transitions. We find the same situation as in the case for $B \to D^*$: The lattice results practically saturate the sum rules, leaving basically no room for excited states.Comment: 8 pages, 5 figure