Bandwidth aspects in second generation current conveyors

This paper discusses bandwidth problems associated with second-generation current conveyors (CCII). In particular, our work is centered in high-capacitance applications, and has been oriented for wireless optical links and applied physics. We discuss techniques for improving bandwidth in these CCIIs, and develop a new CCII structure with larger bandwidth than traditional circuits. These circuits are then compared in terms of their noise and dynamic range characteristics. A test circuit was developed to verify these different bandwidth behaviors

Collider Detection of Dark Matter Electromagnetic Anapole Moments

Dark matter that interacts with the Standard Model by exchanging photons through higher multipole interactions occurs in a wide range of both strongly as well as weakly coupled hidden sector models. We study the collider detection prospects of these candidates, with a focus on Majorana dark matter that couples through the anapole moment. The study is conducted at the effective field theory level with the mono-$Z$ signature incorporating varying levels of systematic uncertainties at the high-luminosity LHC. The projected collider reach on the anapole moment is then compared to the reach coming from direct detection experiments like LZ. Finally, the analysis is applied to a weakly coupled completion with leptophilic dark matter.Comment: 24 pages, 9 figure

The Informativeness of Quarterly Financial Reporting: The Portuguese Case

With the Directive 2004/109/EC, of December 15, 2004 – Transparency Directive –, the European Union decided not to require listed companies to disclose financial information in the first and third quarters of each year. Each EU country now has to decide whether to oblige its companies to disclose this information. Using a sample of 1751 firm-earnings announcements between 1994 and 2004, this paper ascertains the informativeness of quarterly financial reporting in Portugal, one of the seven European countries where the disclosure of such information is currently compulsory in all quarters. Evidence suggests that the information of the first and third quarters, both in terms of price volatility and trading volume, is significant and not inferior to that of the remaining earnings announcements.Capital markets-based research; interim accounting disclosure; market reaction; market regulation