Radio spectrum of the AXP J1810-197 and of its profile components

As part of a European Pulsar Network (EPN) multi-telescope observing campaign, we performed simultaneous multi-frequency observations at 1.4, 4.9 and 8.4 GHz during July 2006 and quasi-simultaneous multi-frequency observations from Decem- ber 2006 until July 2007 at 2.7, 4.9, 8.4, 14.6 and 32 GHz, in order to obtain flux density measurements and spectral features of the 5.5-sec radio-emitting magnetar AXP J1810-197. We monitored the spectral evolution of its pulse shape which consists of a main pulse (MP) and an interpulse (IP). We present the flux density spectrum of the average profile and of the separate pulse components of this first-known radio-emitting transient anomalous X-ray pulsar. We observe a decrease of the flux density by a factor of 10 within 8 months and follow the disappearance of one of the two main components. Although the spectrum is generally flat, we observe large fluctuations of the spectral index with time. For that reason we have made some measurements of modulation indices for individual pulses in order to also investigate the origin of these fluctuations.Comment: accepted for publication in MNRAS, 9 pages, 7 figures, 5 table

Derived counterparts of fusion categories of quantum groups

In this text, we study derived versions of the fusion category associated to Lusztig's quantum group $\textbf{U}_q$. The categories that so arise are non-semisimple but recovers the usual fusion ring when passing to complexified Grothendieck rings. On the derived level it turns out that it is possible to define fusion for $\textbf{U}_q$ without using the notion of tilting modules. Hence, we arrive at a definition of the fusion ring that makes sense in any spherical category. We apply this new definition to the small quantum group and we related with some rings of A. Lachowska

SOCIALLY EFFICIENT ALLOCATION OF GM AND NON-GM CROPS UNDER CONTAMINATION RISK

This paper develops a model of optimal allocation of GM and non-GM crops under contamination risk. The model is used to compare the producer optimal crop allocation at equilibrium to the social efficient crop allocation. From the socially optimum conditions, the paper identifies production environments under which GM crops are more likely to be overplanted.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,