Working group report: Collider Physics

This is summary of the activities of the working group on collider physics in the IXth Workshop on High Energy Physics Phenomenology (WHEPP-9) held at the Institute of Physics, Bhubaneswar, India in January 2006. Some of the work subsequently done on these problems by the subgroups formed during the workshop is included in this report.     

Synthesis of 5H-Triazolo[1,5-d]- and 5H- Tetrazolo- [1,5-d]thieno[3,2-f]-1,4-diazepin-6(7H)-ones

5H-Triazolo[1,5-d]- and 5H-tetrazolo[1,5-d]thieno[3,2-f]-1,4-diazepin-6(7H)-ones have been obtained by the base catalysed ring expansion reaction of 5-chloromethyl-1,2,4-triazolo[1,5-c]- and 5-chloromethyltetrazolo- [1,5-c]thieno[3,2-e]pyrimidines. The required thienopyrimidine derivatives were synthesized from 2-amino-3-triazolyl- and 2-amino-3-tetrazolylthiophenes by acylation, followed by dehydrative cyclization.     

Dielectric loss of poly(vinylacetate) at electric fields of 400 kV/cm

Using quasi-steady-state and time-resolved high-field impedance techniques, the frequency-dependent dielectric permittivity of poly(vinylacetate) has been studied at electric field amplitudes as high as 400 kV/cm. The relative changes of the dielectric loss depend quadratically on the field amplitude and reach about 1 %. The magnitude and frequency-dependence of this non-linear dielectric effect and its time evolution after applying the high field are consistent with energy absorption from the field being at the source of the non-linear behavior. Based upon a phenomenological model of heterogeneous dynamics at isothermal conditions, the observed changes can be explained by locally increased configurational temperatures and the resulting accelerated dynamics.     

On the singularity of Green's tensor for a perfectly conducting semi-infinite cone

This paper is intended to clarify a misunderstanding concerningthe source singularity of the electric Green's tensor for aperfectly conducting semi-infinite cone of circular cross-section.Tai's series expansion of the Green's tensor is known to lacka singular term at the source region. Jones has reconstructedthe solution to this problem and has pointed out the differencebetween his result and that of Tai. The aim of our paper isto demonstrate that, although Jones's closed-form solution iscorrect, there is a mistake in his comparison with Tai's seriessolution. We conclude that one of the two additional singularterms that Jones claims as missing from Tai's formula must beomitted. Besides, we compare Jones's closed-form solution withSmyshlyaev's solution to the very same problem. We concludethat the magnetic field expressions given by Jones and Smyshlyaevcoincide, but a singular term is missing from Smyshlyaev's expressionfor the electric field.     

Heterocyclization of functionalized ketene acetals: Synthesis of pyrimidines via vinylamidine intermediates

Stable N-(carbethoxycyanovinyl)amidines have been isolated from the reaction of benzamidine with carbethoxycyanoketene S,N-acetals and have been found to cyclize to 4-chloro-, 4-amino- and 4-hydroxypyrimidines depending upon the cyclizing agent employed.     

Scattering by small defects in the neighbourhood of a fluid-solid interface

The scattering of incident plane elastic waves by a varietyof different defects that lie upon a fluid-solid interface isconsidered here using matched asymptotic expansions. The expansionscheme is developed in terms of a parameter , the ratio of typicaldefect length scale to a typical wavelength of the incidentfield, taken to be small. Three different canonical situations occur and these are illustratedvia three specific examples treated here: a rigid strut, anedge crack, and a rigid strip. In each case the leading-ordermatching is performed to identify the leading-order contributionof the defect to the acoustic field in the far field. In particular,each defect is identified with a source of dipole response ininterfacial stress of displacement. It is shown in the limit as s<<s1 that in the inner problemsthe fluid and solid pieces uncouple in a particularly convenientmanner allowing analytical solutions to be deduced. These arethen matched with appropriate outer solutions.     

Reaction of nitriles under acidic conditions. Part I. A general method of synthesis of condensed pyrimidines

Nitriles are known to give rise to salts of different compositions with halogen acids. Many of the reactions undergone by nitriles under the influence of halogen acids are, in many cases, assumed to proceed via the intermediate formation of highly reactive imidoyl derivatives. The intermediates produced, in situ, by the reaction of nitriles with hydrogen chloride should, in principle, be capable of reacting with compounds containing appropriately placed nucleophilic and electrophilic centers leading to the formation of a heterocycle incorporating the C=N of the nitrile. Thus, the reaction of aliphatic, aromatic and heterocyclic nitriles with a variety of ortho aminocarbonyl derivatives such as nitriles, amides, esters and ketones of benzene, thiophen, furan, pyrrole, benzothiophene and pyridothiophene have been found to yield the corresponding condensed pyrimidines in fair to good yields. This constitutes a facile and versatile one-pot synthesis of condensed pyrimidines.     

B and collider physics: Working group report

This report summarises the work done during WHEPP-6 (Institute of Mathematical Sciences, Chennai, India, Jan 3–15, 2000) in Working group on ‘B and collider physics’.