Limited Liability and the Known Unknown

Limited liability is a double-edged sword. On the one hand, limited lia-bility may help overcome investors’ risk aversion and facilitate capital formation and economic growth. On the other hand, limited liability is widely believed to contribute to excessive risk-taking and externaliza-tion of losses to the public. The externalization problem can be mitigated imperfectly through existing mechanisms such as regulation, mandatory insurance, and minimum capital requirements. These mechanisms would be more effective if information asymmetries between industry and poli-cymakers were reduced. Private businesses typically have better infor-mation about industry-specific risks than policymakers. A charge for limited liability entities—resembling a corporate income tax but calibrated to risk levels—could have two salutary effects. First, a well-calibrated limited liability tax could help compensate the public fisc for risks and reduce externalization. Second, a limited liability tax could force private industry actors to reveal information to policymakers and regulators, thereby dynamically improving the public response to externalization risk. Charging firms for limited liability at initially similar rates will lead relatively low-risk firms to forgo limited liability, while relatively high-risk firms will pay for limited liability. Policymakers will then be able to focus on the industries whose firms have self-identified as high risk, and thus develop more finely tailored regulatory responses. Because the ben-efits of making the proper election are fully internalized by individual firms, whereas the costs of future regulation or limited liability tax changes will be borne collectively by industries, firms will be unlikely to strategically mislead policymakers in electing limited or unlimited lia-bility. By helping to reveal private information and focus regulators’ at-tention, a limited liability tax could accelerate the pace at which poli-cymakers learn, and therefore, the pace at which regulations improve

Search for neutrinoless double beta decay with the NEMO-3 detector: first results

The NEMO-3 detector, which has been operating in the Frejus Underground Laboratory since February 2003, is devoted to searching for neutrinoless double beta decay (\beta\beta 0 \nu). The expected performance of the detector has been successfully achieved. Half-lives of the two neutrinos double beta decay (\beta\beta 2 \nu$) have been measured for ^{100} Mo, ^{82}Se, ^{96}Zr, ^{116}Cd and ^{150}Nd. After 265 days of data collection from February 2003 until March 2004, no evidence for neutrinoless double beta decay (\beta\beta 0 \nu) was found from \sim 7 kg of ^{100} Mo and \sim 1 kg of ^{82} Se. The corresponding lower limits for the half-lives are 3.5 \times 10^{23} years at 90% C.L for ^{100} Mo and 1.9 \times 10^{23} years for ^{82}Se. Limits for the effective Majorana neutrino mass are < \hspace{-0.5mm} m_{\nu} \hspace{-0.5mm} > < 0.7-1.2 eV for ^{100} Mo and \linebreak < \hspace{-0.5mm} m_{\nu \hspace{-0.5mm} > < 1.3-3.2 eV for ^{82}Se. Radon is the dominant background today and a Radon-free purification system will be in operation by the end of september 2004. The NEMO-3 expected sensitivity after 5 years of data is 0.2 eV.Comment: 5 pages, 4 figures, invited talk given at the 21st International Conference on Neutrino Physics and Astrophysics, (Neutrino 2004) 14-19 June 2004, College de France - Pari

Longitudinal vector form factors in weak decays of nuclei

The longitudinal form factors of the weak vector current of particles with spin $J = 1/2$ and isospin $I = 1/2$ are determined by the mass difference and the charge radii of members of the isotopic doublets. The most promising reactions to measure these form factors are the reactions with large momentum transfers involving the spin-1/2 isotopic doublets with a maximum mass splitting. Numerical estimates of longitudinal form factors are given for nucleons and eight nuclear spin-1/2 isotopic doublets.Comment: 6 pages. Talk given at the 10th MEDEX'15 meeting Matrix Elements for the Double-beta-decay Experiments, Prague, June 9-12, 201