Proton albedo spectrum observation in low latitude region at Hyderabad, India

The flux and the energy spectrum of low energy (30-100 MeV) proton albedos, have been observed for the first time in a low latitude region, over Hyderabad, India. The preliminary results, based on the quick look data acquisition and display system are presented. A charged particle telescope, capable of distinguishing singly charged particles such as electrons, muons, protons in low energy region, records the data of both upward as well as downward moving particles. Thus spectra of splash and re-entrant albedo protons have been recorded simultaneously in a high altitude Balloon flight carried out on 8th December, 1985, over Hyderabad, India. Balloon floated at an latitude of approx. 37 km (4 mb)

A bi-directional charged particle telescope to observe flux, energy spectrum and angular distribution of relativistic and non-relativistic particles

A Charged Particle Telescope (CPT) was designed, fabricated and calibrated to make the following observations: (1) discrimination between various singly charged particles, e.g., electrons, muons and protons, in about 5 to 100 MeV energy range; (2) measurement of the flux and the energy of the charged particles incident to the telescope from two opposite directions and stopping in the telescope, thus obtaining flux and energy spectrum of downward and upward moving charged particles; and (3) measurement of the broad angular distribution of selected particles as a function of azimuthal angle. This telescope can be used to study low energy electron, muon and proton energy spectra. The experiment was flown in a high altitude balloon from Hyderabad, India, in December 1984. This same equipment is also useful in ground level electron, muon spectrum study

Effect of some feed filament parameters and weave on compressional properties of air-jet textured yarn fabrics

The influence of some feed filament parameters and weave on compression and recovery behaviour of air-jet textured yarn fabrics has been studied and compared with their corresponding parent yarn fabrics. Fabric low load compression-recovery behaviour has been analysed by defining initial thickness, compression parameter, recovery parameter and resiliency. Fabrics made from coarser yarn (larger total yarn dtex) have higher initial thickness and compression parameter while lower recovery parameter and resiliency, as compared to fabrics made from finer yarn. Fabrics are woven with two woven structures, namely plain and twill weave to assess the effect of fabric structure on compression and recovery behaviour of the fabrics. Twill woven fabrics exhibit a higher value of all compressional parameters compared to their equivalent plain woven fabrics. Parent yarn fabrics exhibit a low value of all compressional properties, irrespective of change in any feed yarn characteristics as compared to their equivalent textured yarn fabrics

Effect of linear density of feed yarn filaments and air-jet texturing process variables on compressional properties of woven fabrics

The influence of yarn feed and process parameters used in the production of air-jet textured yarn on compression and recovery behavior of air-jet textured yarn fabric has been studied. Yarn linear density per filament and air-jet texturing process parameters, such as overfeed, air pressure and texturing speed are the key factors which influence yarn structure and hence fabric properties. The individual effect of feed yarn properties and air-jet process variables in the production of air-jet textured yarn has been studied in term of potential contribution and normalized regression coefficient on fabric low load compression behavior. Fabric low load compression-recovery behavior has been analyzed by defining compression parameter, recovery parameter and resiliency. Analysis shows that most dominating factor to explain the air-jet textured yarn fabric low-load compression properties is overfeed percentage, while linear density per filament is most dominating factor affecting fabric resiliency

Effect of some feed filament parameters and weave on compressional properties of air-jet textured yarn fabrics

9-13The influence of some feed filament parameters and weave on compression and recovery behaviour of air-jet textured yarn fabrics has been studied and compared with their corresponding parent yarn fabrics. Fabric low load compression-recovery behaviour has been analysed by defining initial thickness, compression parameter, recovery parameter and resiliency. Fabrics made from coarser yarn (larger total yarn dtex) have higher initial thickness and compression parameter while lower recovery parameter and resiliency, as compared to fabrics made from finer yarn. Fabrics are woven with two woven structures, namely plain and twill weave to assess the effect of fabric structure on compression and recovery behaviour of the fabrics. Twill woven fabrics exhibit a higher value of all compressional parameters compared to their equivalent plain woven fabrics. Parent yarn fabrics exhibit a low value of all compressional properties, irrespective of change in any feed yarn characteristics as compared to their equivalent textured yarn fabrics

Effect of linear density of feed yarn filaments and air-jet texturing process variables on compressional properties of fabrics

Effect of filament fineness and process parameters employed in the production of air-jet textured yarns has been studied on the compression and recovery of union fabrics made from air-jet textured yarns as weft and twisted filament yarns as warp. Filament linear density and process parameters such as overfeed, air pressure and texturing speed affect the textured yarn structure and hence fabric properties. The individual effect of filament fineness and process variables in the production of air-jet textured yarn has been studied in terms of potential contribution and normalized regression coefficient on fabric low load compression behavior. Fabric low load compression-recovery behavior has been analyzed in terms of compression parameter, recovery parameter and resiliency. Analysis shows that most dominating factor to explain the low load compression properties of air-jet textured yarn fabric is overfeed percentage, while linear density per filament is most dominating factor affecting fabric resiliency

Search for TeV γ\gamma -rays from H1426+428 during 2004-07 with the TACTIC telescope

The BL Lac object H1426+428 ($z\equiv 0.129$) is an established source of TeV $\gamma$-rays and detections of these photons from this object also have important implications for estimating the Extragalactic Background Light (EBL) in addition to the understanding of the particle acceleration and $\gamma$-ray production mechanisms in the AGN jets. We have observed this source for about 244h in 2004, 2006 and 2007 with the TACTIC $\gamma$-ray telescope located at Mt. Abu, India. Detailed analysis of these data do not indicate the presence of any statistically significant TeV $\gamma$-ray signal from the source direction. Accordingly, we have placed an upper limit of $\leq1.18\times10^{-12}$ $photons$ $cm^{-2}$ $s^{-1}$ on the integrated $\gamma$-ray flux at 3$\sigma$ significance level.Comment: 11 pages, 5 figures accepted for publication in Journal of Physics G: Nuclear and Particle Physic

Constraining a possible time variation of the gravitational constant G with terrestrial nuclear laboratory data

Testing the constancy of the gravitational constant G has been a longstanding fundamental question in natural science. As first suggested by Jofr\'{e}, Reisenegger and Fern\'{a}ndez [1], Dirac's hypothesis of a decreasing gravitational constant $G$ with time due to the expansion of the Universe would induce changes in the composition of neutron stars, causing dissipation and internal heating. Eventually, neutron stars reach their quasi-stationary states where cooling due to neutrino and photon emissions balances the internal heating. The correlation of surface temperatures and radii of some old neutron stars may thus carry useful information about the changing rate of G. Using the density dependence of the nuclear symmetry energy constrained by recent terrestrial laboratory data on isospin diffusion in heavy-ion reactions at intermediate energies and the size of neutron skin in $^{208}Pb$ within the gravitochemical heating formalism, we obtain an upper limit of the relative changing rate of $|\dot{G}/G|\le4\times 10^{-12}yr^{-1}$ consistent with the best available estimates in the literature.Comment: 27 pages, 11 figures, and 2 tables. Accepted version to appear in PRC (2007

Evaluation of safed musH (Chlorophytum borivilianum Santapau & Fernandes) germplasm

Safed musU (Ch 10 rophy tum borivilianum Santapau & Fernandes), an herbaceous plant belonging to the family liliaceae is mostly collected from wild sources as its tubers are in high demand in indigenous systems of medicine in the preparation of a aphrodesiac drug for curing general debility. Safed musH germplasm were evaluated for their performance. A large variability was observed in terms of morphological and yield attributing characters and tuber yield among the germplasm. CB/MS-6 gave highest number of leaves planrl (23.S), number of tubers planrl (10.2), tuber thickness (0.80 cm) and fresh (65.3 g planrl) and dry (S.5 g plant-I) tuber yield. Further, two distinct plant types (prostrate or spreading and erect) were observed among these accessions. Observations on the crop grown in farmer's field in different locations revealed the feasibility of its cultivation in semi arid areas of Andhra Pradesh, Madhya Pradesh and Maharashtra. &nbsp