A possible observational evidence for θ−2\theta^{-2} angular distribution of opening half-angle of GRB jets

We propose a method to estimate the pseudo jet opening half-angle of GRBs using the spectral peak energy (\Ep)--peak luminosity relation (so called Yonetoku relation) as well as the \Ep--collimation-corrected $\gamma$-ray energy relation (so called Ghirlanda relation). For bursts with known jet break times and redshifts, we compared the pseudo jet opening half-angle with the standard one and found that the differences are within a factor 2. We apply the method to 689 long GRBS. We found that the distribution function of the pseudo jet opening half-angle obeys $f(\theta_j)\propto\theta_j^{-2.2 \pm 0.2}$ with possible cutoffs for $\theta_j 0.3$ although the log-normal fit is also possible. $\theta^{-2}$ distribution is compatible with the structured jet model. From the distribution function we found that the beaming correction for the rate of GRBs is $\sim 340$, which means $\sim 10^{-5}$ yr$^{-1}$ galaxy$^{-1}$ or only one in $10^2$ type Ib/c supernovae. We also found the evolution of the distribution function as a function of the redshift.Comment: 5 pages, 5 figures, submitted to MNRA

Lining of cast iron cylinder with copper alloy utilising high temperature oxidation

Lining the inner surface of a cast iron hydraulic cylinder with copper alloy would generally not be possible. In this study, the surface of a cast iron cylinder was decarburised by high temperature oxidation. The cylinder, after decarburisation, was filled with borax anhydride and heated at a temperature of 1203 K. Molten copper alloy was then injected into the cylinder, displacing the molten borax anhydride. After cooling, the embedded copper alloy was drilled along its centre axis so that a prescribed thickness of the copper alloy remained. Thus, the cast iron cylinder could be successfully lined with copper alloy

Nucleotide sequence of the genes, encoding the pentaheme cytochrome (dmsC) and the transmembrane protein (dmsB) involved in dimethyl sulfoxide respiration from Rhodobacter sphaeroides f. sp. denitrificans

AbstractThe nucleotide sequence of the genes encoding a pentaheme cytochrome (dmsC) and a transmembrane protein (dmsB) were determined upstream of the dmsA gene encoding dimethyl sulfoxide reductase from Rhodobacter sphaeroides f. sp. denitrificans. dmsC and dmsB encode proteins of 404 and 226 amino acid residues, which show 40% and 26% identity to the pentaheme cytochrome TorC and the transmembrane protein TorD, respectively, of the trimethylamine N-oxide reduction system in Escherichia coli

Rammohan Roy\u27s Views on the Judicial System (2)

The first part containing an Introduction and the first two chapters has been published in No. 64 of this Bulletin.This part consists of four chapters: Chap.3 Company\u27s Court of Justice, Chap.4 European Judges, Chap.5 Indian Judges, Law Officers and Pleaders, and Chap.6 Jury.The resume will be presented in the concluding part of this article