Massive galaxies with very young AGN

Gigahertz Peaked Spectrum (GPS) radio galaxies are generally thought to be the young counterparts of classical extended radio sources and live in massive ellipticals. GPS sources are vital for studying the early evolution of radio-loud AGN, the trigger of their nuclear activity, and the importance of feedback in galaxy evolution. We study the Parkes half-Jansky sample of GPS radio galaxies of which now all host galaxies have been identified and 80% has their redshifts determined (0.122 < z < 1.539). Analysis of the absolute magnitudes of the GPS host galaxies show that at z > 1 they are on average a magnitude fainter than classical 3C radio galaxies. This suggests that the AGN in young radio galaxies have not yet much influenced the overall properties of the host galaxy. However their restframe UV luminosities indicate that there is a low level of excess as compared to passive evolution models.Comment: To appear in the proceedings of "Formation and Evolution of Galaxy Bulges", IAUS 245; M. Bureau, E. Athanassoula & B. Barbuy, ed

Contests with rank-order spillovers

This paper presents a unified framework for characterizing symmetric equilibrium in simultaneous move, two-player, rank-order contests with complete information, in which each player’s strategy generates direct or indirect affine “spillover” effects that depend on the rank-order of her decision variable. These effects arise in natural interpretations of a number of important economic environments, as well as in classic contests adapted to recent experimental and behavioral models where individuals exhibit inequality aversion or regret. We provide the closed-form solution for the symmetric Nash equilibria of this class of games, and show how it can be used to directly solve for equilibrium behavior in auctions, pricing games, tournaments, R&D races, models of litigation, and a host of other contests. – Contests ; auctions ; spillovers -- Dieser Artikel entwickelt einen einheitlichen Rahmen zur Charakterisierung des symmetrischen Gleichgewichts eines Wettkampfes unter vollständiger Information, in dem zwei Spieler gleichzeitig ihren Einsatz wählen und die Strategie eines Spielers direkte oder indirekte Auswirkung auf den Gegenspieler hat. Diese Externalität hängt entscheidend von der Rangfolge der Entscheidungsvariablen ab. Solche Effekte finden sich in einer Vielzahl wichtiger ökonomischer Problemstellungen. Auch typische Wettkämpfe können in diesem Rahmen analysiert werden, wenn sie im Sinne jüngster experimenteller und verhaltensorientierter Modelle angepasst werden und angenommen wird, dass Individuen eine Abneigung gegen Ungleichheit haben oder Bedauern empfinden, falls sie einen unnötig hohen Einsatz gewählt haben. Wir geben das symmetrische Nash- Gleichgewicht für diese Klasse von Spielen an und zeigen, wie es direkt angewendet werden kann, um das gleichgewichtige Verhalten in Auktionen, Preissetzungsspielen, Wettkämpfen, Wettbewerb um Forschung und Entwicklung, Modellen für Rechtsstreitigkeiten und einer Reihe weiterer Wettkämpfe zu analysieren.

Comparative Analysis of Litigation Systems: An Auction-Theoretic Approach

A simple auction-theoretic framework is used to examine symmetric litigation environments where the legal ownership of a disputed asset is unknown by the court. The court observes only the quality of the case presented by each party, and awards the asset to the party presenting the best case. Rational litigants influence the quality of their cases by hiring skillful attorneys. This framework permits us to compare the equilibrium legal expenditures that arise under a continuum of legal systems. The British rule, American rule, and some recently proposed legal reforms are special cases of our model.auctions, contests, litigation, fee-shifting

Comparative Analysis of Litigation Systems: An Auction-Theoretic Approach

A simple auction-theoretic framework is used to examine symmetric litigation environments where the legal ownership of a disputed asset is unknown by the court. The court observes only the quality of the case presented by each party, and awards the asset to the party presenting the best case. Rational litigants influence the quality of their cases by hiring skillful attorneys. This framework permits us to compare the equilibrium legal expenditures that arise under a continuum of legal systems. The British rule, American rule, and some recently proposed legal reforms are special cases of our model. ZUSAMMENFASSUNG - (Vergleichende Analyse von Prozeßsystemen: Ein auktionstheoretischer Ansatz) Anhand eines einfachen auktionstheoretischen Ansatzes werden symmetrische Prozeßumwelten untersucht, bei denen der Eigentümer des Streitgegenstandes dem Gericht nicht bekannt ist. Das Gericht kann nur die Qualität der durch die einzelnen Parteien präsentierten Argumente beobachten und dann jener Partei den Vermögenszuschlag geben, die die besten Argumente präsentiert hat. Rationale Prozeßparteien beeinflussen die Qualität ihrer Argumente durch den Einsatz geschickter Anwälte. Der gewählte Ansatz erlaubt es, die im Gleichgewicht entstehenden Prozeßkosten für ein Kontinuum von Rechtssystemen zu vergleichen. Die britische Rechtsregelung, die amerikanische Rechtsregelung und einige jüngst vorgeschlagene Rechtsformen sind Spezialfälle des vorgestellten Modells.Auctions; Contests; Litigation; Fee-Shifting

The Herodotus Paradox

The Babylonian bridal auction, described by Herodotus, is regarded as one of the earliest uses of an auction in history. Yet, to our knowledge, the literature lacks a formal equilibrium analysis of this auction. We provide such an analysis for the two-player case with complete and incomplete information, and in so doing identify what we call the “Herodotus Paradox.”

Contests with Rank-Order Spillovers

This paper presents a unified framework for characterizing symmetric equilibrium in simultaneous move, two-player, rank-order contests with complete information, in which each player’s strategy generates direct or indirect affine “spillover” effects that depend on the rank-order of her decision variable. These effects arise in natural interpretations of a number of important economic environments, as well as in classic contests adapted to recent experimental and behavioral models where individuals exhibit inequality aversion or regret. We provide the closed-form solution for the symmetric Nash equilibria of this class of games, and show how it can be used to directly solve for equilibrium behavior in auctions, pricing games, tournaments, R&D races, models of litigation, and a host of other contests.

Tortuous ways to the extraction of neutron observables from inclusive lepton scattering

We analyze new JLAB data for inclusive electron scattering on various targets. Computed and measured total inclusive cross sections in the range $0.3\lesssim x\lesssim 0.95$ show on a logarithmic scale reasonable agreement for all targets. However, closer inspection of the Quasi-Elastic components bares serious discrepancies. EMC ratios which may contain less systematic errors fare the same. The above observations for the new data do not enable the extraction of the magnetic form factor (FF) $G_M^n$ and the Structure Function (SFs) $F_2^n$ of the neutron, although the application of exactly the same analysis to older data had been successful. We add to the above analysis older CLAS collaboration on $F_2^D$. Removing some scattered points, it appears possible to obtain the above mentioned neutron information. We compare our results with others from alternative sources. Particular attention is paid to the A=3 iso-doublet. Present data exist only for $^3$He, but the available input and charge symmetry also enable computations for $^3$H. Their average is the computed iso-scalar part and is compared with the empirical modification of $^3$He towards a fictitious A=3 iso-singlet.Comment: 27 pages, 30 figure

Deuteron Magnetic Quadrupole Moment From Chiral Effective Field Theory

We calculate the magnetic quadrupole moment (MQM) of the deuteron at leading order in the systematic expansion provided by chiral effective field theory. We take into account parity and time-reversal violation which, at the quark-gluon level, results from the QCD vacuum angle and dimension-six operators that originate from physics beyond the Standard Model. We show that the deuteron MQM can be expressed in terms of five low-energy constants that appear in the parity- and time-reversal-violating nuclear potential and electromagnetic current, four of which also contribute to the electric dipole moments of light nuclei. We conclude that the deuteron MQM has an enhanced sensitivity to the QCD vacuum angle and that its measurement would be complementary to the proposed measurements of light-nuclear EDMs

Faint, Evolving Radio AGN in SDSS Luminous Red Galaxies

We detect and study the properties of faint radio AGN in Luminous Red Galaxies (LRGs). The LRG sample comprises 760,000 objects from a catalog of LRG photometric redshifts constructed from the Sloan Digital Sky Survey (SDSS) imaging data, and 65,000 LRGs from the SDSS spectroscopic sample. These galaxies have typical 1.4 GHz flux densities in the 10s-100s of microJy, with the contribution from a low-luminosity AGN dominating any contribution from star formation. To probe the radio properties of such faint objects, we employ a stacking technique whereby FIRST survey image cutouts at each optical LRG position are sorted by the parameter of interest and median-combined within bins. We find that median radio luminosity scales with optical luminosity (L_opt) as L_1.4 GHz ~ L_opt^(beta), where beta appears to decrease from beta ~ 1 at z = 0.4 to beta ~ 0 at z = 0.7, a result which could be indicative of AGN cosmic downsizing. We also find that the overall LRG population, which is dominated by low-luminosity AGN, experiences significant cosmic evolution between z = 0.2 and z = 0.7. This implies a considerable increase in total AGN heating for these massive ellipticals with redshift. By matching against the FIRST catalog, we investigate the incidence and properties of LRGs associated with double-lobed (FR I/II) radio galaxies. (Abridged)Comment: 12 pages, 9 figures, Accepted by A

Trehalose is required for the acquisition of tolerance to a variety of stresses in the filamentous fungus Aspergillus nidulans

Trehalose is a non-reducing disaccharide found at high concentrations in Aspergillus nidulans conidia and rapidly degraded upon induction of conidial germination. Furthermore, trehalose is accumulated in response to a heat shock or to an oxidative shock. The authors have characterized the A. nidulans tpsA gene encoding trehalose-6-phosphate synthase, which catalyses the first step in trehalose biosynthesis. Expression of tpsA in a Saccharomyces cerevisiae tps1 mutant revealed that the tpsA gene product is a functional equivalent of the yeast Tps1 trehalose-6-phosphate synthase. The A. nidulans tpsA-null mutant does not produce trehalose during conidiation or in response to various stress conditions. While germlings of the tpsA mutant show an increased sensitivity to moderate stress conditions (growth at 45 °C or in the presence of 2 mM H2O2), they display a response to severe stress (60 min at 50 °C or in the presence of 100 mM H2O2) similar to that of wild-type germlings. Furthermore, conidia of the tpsA mutant show a rapid loss of viability upon storage. These results are consistent with a role of trehalose in the acquisition of stress tolerance. Inactivation of the tpsA gene also results in increased steady-state levels of sugar phosphates but does not prevent growth on rapidly metabolizable carbon sources (glucose, fructose) as seen in Saccharomyces cerevisiae. This suggests that trehalose 6-phosphate is a physiological inhibitor of hexokinase but that this control is not essential for proper glycolytic flux in A. nidulans. Interestingly, tpsA transcription is not induced in response to heat shock or during conidiation, indicating that trehalose accumulation is probably due to a post-translational activation process of the trehalose 6-phosphate synthase