Large magnetic field effect on back electron transfer from uncharged radical to its cationic partner in anionic micelle

The magnetic field effect (MFE) on the radical pair (RP) generated by photoexcitation of the acetyl derivative of phenyl pyrylium ion (APP⁺) in the presence of biphenyl, an electron donor, has been investigated. The escape yield at 3.5 T is more than ten times the zero-field value. The MFE reaches near-saturation twice, once at fields of the order of 10mT and again at about 3.5 T. The low-field variation of the MFE conforms to the pattern expected for the isotropic HFC mechanism, and the high-field variation to that expected for the relaxation mechanism. In this particular system two types of radical pair are generated, one by electron transfer from the donor to the acceptor and another by H-abstraction from the micelle. The MFEs on the two types of ³RP have been compared.     

SuSeFLAV: A program for calculating supersymmetric spectra and lepton flavour violation

The program SuSeFLAV is introduced for computing supersymmetric mass spectra with flavour violation in various supersymmetric breaking scenarios with/without see-saw mechanism. A short user guide summarizing the compilation, executables and the input files is provided.     

Conditions for Optimal Scheduling for the Three-machine Problem

This note proposes a simpler formulation for the conditionssuggested by Eltman & Townsend for the three-machine problem,which if satisfied must result in one job preceding anotherin an optimal sequence. These are compared with Johnson's conditions.     

Results from PAMELA,ATIC and FERMI: Pulsars or dark matter?

It is well known that dark matter dominates the dynamics of galaxies and clusters of galaxies. Its constituents remain a mystery despite an assiduous search for them over the past three decades. Recent results from the satellite-based PAMELA experiment show an excess in the positron fraction at energies between 10 and 100 GeV in the secondary cosmic ray spectrum. Other experiments, namely ATIC, HESS and FERMI, show an excess in the total electron (e ⁺ + e ⁻) spectrum for energies greater than 100 GeV. These excesses in the positron fraction as well as the electron spectrum can arise in local astrophysical processes like pulsars, or can be attributed to the annihilation of the dark matter particles. The latter possibility gives clues to the possible candidates for the dark matter in galaxies and other astrophysical systems. In this article, we give a report of these exciting developments.     

A model of evaluating the pseudogap temperature for high-temperature superconductors

We have presented a model of evaluating the pseudogap temperature for high-temperature superconductors using paraconductivity approach. The theoretical analysis is based on the crossing point technique of the conductivity expressions. The pseudogap temperature T^? is found to depend on dimension and is calculated for 2D and 3D superconducting samples. Numerical calculation is given in favour of the YBCO and doped SmFeAsO_1?x samples.     

Flavoured co-annihilation

In minimal supergravity (mSUGRA) or CMSSM, one of the main co-annihilating partners of the neutralino is the lightest stau, $\tilde{\tau}_1$ . In the presence of flavour violation in the right-handed sector, the co-annihilating partner would be a flavour mixed state. The flavour effect is two-fold: (a) It changes the mass of $\tilde{\tau}_{1}$ , thus modifying the parameter space of the co-annihilation and (b) flavour violating scatterings could now contribute to the cross-sections in the early Universe. In fact, it is shown that for large enough ??~0.2, these processes would constitute the dominant channels in co-annihilation regions. The amount of flavour mixing permissible is constrained by flavour violating ?????? or ????e processes. For ??_RR mass insertions, the constraints from flavour violation are not strong enough in some regions of the parameter space due to partial cancellations in the amplitudes. In mSUGRA, the regions with cancelations within LFV amplitudes do not overlap with the regions of co-annihilations. In non-universal Higgs model (NUHM), however, these regions do overlap leading to significant flavoured co-annihilations. At the LHC and other colliders, these regions can constitute for interesting signals.