Observations of GRB 100724B with the Fermi Gamma-Ray Burst Monitor (GBM) find that the spectrum is dominated by the typical Band functional form, which is usually taken to represent a non-thermal ...emission component, but also includes a statistically highly significant thermal spectral contribution. The simultaneous observation of the thermal and non-thermal components allows us to confidently identify the two emission components. The fact that these seem to vary independently favors the idea that the thermal component is of photospheric origin while the dominant non-thermal emission occurs at larger radii. Our results imply either a very high efficiency for the non-thermal process, or a very small size of the region at the base of the flow, both quite challenging for the standard fireball model. These problems are resolved if the jet is initially highly magnetized and has a substantial Poynting flux.
The synthesis and activity on the central nervous system of a series of 2-aryl or 2-alkyl-7-phenylhexahydroimidazo1,5-a pyrazin-3(2H)-ones (II a-f) are reported. The intermediate ...3-carbomethoxy-1-phenylpiperazine (X) was prepared in six steps from aniline and methyl-2-chloroacrylate. Compared with that of derivatives of Zetidoline, the depressant activity of (II a-f) is markedly reduced.
