Prospects of Dark Matter Direct Search under Deep Sea Water in India

There is compelling evidence from cosmological and astrophysical observations that about one quarter of theenergy density of the universe can be attributed to cold dark matter (CDM), whose nature and properties are still unknown. Around the world large numbers of experiments are using different techniques of dark matter direct and indirect detections. According to their experimental requirements location of the experiment prefer to use either underground, under ice, or under sea water. In a country like India, digging underground cavern and long tunnel is not very convenient. Therefore, authors look from the other solutions of this problem preferring to use deep sea water. In this article, we discuss the pros and corns of use of deep sea water in the dark matter search

Applications of Hubble Volume in Atomic Physics, Nuclear Physics, Particle Physics, Quantum Physics and Cosmic Physics

In this paper an attempt is made to emphasize the major shortcomings of standard cosmology. It can be suggested that, the current cosmological changes can be understood by studying the atom and the atomic nucleus through ground based experiments. If light is coming from the atoms of the gigantic galaxy, then redshift can be interpreted as an index of the galactic atomic ‘light emission mechanism’. In no way it seems to be connected with ‘galaxy receding’. With ‘cosmological increasing (emitted) photon energy’, observed cosmic redshift can be considered as a measure of the age difference between our galaxy and any observed galaxy. If it is possible to show that, (from the observer) older galaxy’s distance increases with its ‘age’, then ‘galaxy receding’ and ‘accelerating universe’ concepts can be put for a revision at fundamental level. At any given cosmic time, the product of ‘critical density’ and ‘Hubble volume’ gives a characteristic cosmic mass and it can be called as the ‘Hubble mass’. Interesting thing is that, Schwarzschild radius of the ‘Hubble mass’ again matches with the ‘Hubble length’. Most of the cosmologists believe that this is merely a coincidence. At any given cosmic time,’Hubble length’ can be considered as the gravitational or electromagnetic interaction range. If one is willing to think in this direction, by increasing the number of applications of Hubble mass and Hubble volume in other areas of fundamental physics like quantum physics, nuclear physics, atomic physics and particle physics - slowly and gradually - in a progressive way, concepts of ‘Black hole Cosmology’ can be strengthened and can also be confirmed

Alignment Studies for Tungsten Near L3 Sub-Shell Threshold Via Theoretical, Experimental and Empirical Methods

Alignment studies are made for tungsten near L3 sub-shell threshold using theoretical, experimental and empirical approaches. Experimentally to measure alignment parameter, the angular distribution of L x-rays of tungsten (W-74) is measured in the angular range 0° to 120°, where maximum anisotropy is expected. The experimental measurements are performed in XRF laboratories of Raja Ramanna Center for Advanced Technology (RRCAT), Indore, India using a three-dimensional double reflection set-up. The weighted average of alignment values with 10% error comes 0.155 ± 0.009. Theoretically, the value of alignment parameter A20 is calculated using non-relativistic dipole approximation in a point Coulomb potential and is found 0.151 at L3 threshold energy (10.676 keV). For empirical A20 evaluations, IGELCS interpolated experimental LXRF cross-section σ*Lg (g = α, ℓ) values of Mann et al with 8% reported errorsare used along with the radiative decay rates. The comparison among theoretical, experimental and empirical values are similar and values being >0.1 at L3 threshold energy are certainly higher than the 5 to 8 percent uncertainties quoted in earlier experimental results

Partial as Well as Total Photon Interaction Effective Atomic Numbers for Some Concretes

Photon interaction effective atomic number (Zeff) for partial as well as total photon interaction processes has been computed using logarithmic interpolation method for seven different concretes viz. (i) Ordinary, (ii) Hematite - Serpentine, (iii) Ilmenite - Limonite, (iv) Basalt - magnetite, (v) Ilmenite, (vi) Steel - scrap and (vii) Steel - magnetite concrete in the wide energy range from 10.0 keV to 100 GeV. It has been concluded that this method has an advantage over the atomic to electronic cross-section ratio method especially for mixtures in the intermediate energy level. However, due to lack of experimental data in the higher energy region, it is difficult to discuss, its validity in these energy regions

Third Harmonic Generation of a Short Pulse Laser in a Tunnel Ionizing Plasma: Effect of Self-Defocusing

Third harmonic generation of a Gaussian short pulse laser in a tunnel ionizing plasma is investigated. A Gaussian short pulse laser propagating through a tunnel ionizing plasma generates third harmonic wave. Inhomogeneity of the electric field along the wavefront of the fundamental laser pulse causes more ionization along the axis of propagation while less ionization off axis, leading to strong density gradient with its maximum on the axis of propagation. The medium acts like a diverging lens and pulse defocuses strongly. The normalized third harmonic amplitude varies periodically with the distance with successive maxima acquiring lower value. The self-defocusing of the fundamental laser pulse decays the intensity of the third harmonic pulse

Surface Wear Studies in Some Materials Using α-induced Reactions

The radio-activity produced during the irradiation of 63,65Cu, 59Co, 93Nb and 121,123Sb targets with α-particles have been measured using activation technique. he yields of radioactive isotopic products 66,67,68 Ga, 61 Cu, 96g,mTc and 123,124,126I have been determined in the energy range ≈ 10-40 MeV using stacked foil Technique. Radioactive counting of samples was performed with a high-resolution gamma-spectrometer. As light ion beams produce an extremely narrow layer of activities in the surface of a material, these reactions may be useful for thin layer activation study

Cluster Radioactivity in 127I

Using the preformation cluster model of Gupta and collaborators we have studied all the possible cluster decay modes of 127 I. The calculated half-lives are compared with recently measured lower limits of cluster decay half-lives (for the clusters like 24Ne, 28Mg, 30Mg, 32Si, 34Si, 48Ca and 49Sc) of 127I. Our calculated half-life values lies well above the experimentally measured lower limits and the trend of the values also matches with experimental ones

Elemental Analysis of Nanomaterial Using Photon-Atom Interaction Based EDXRF Technique

Presence of trace amount of foreign impurities (both metallic and non-metallic) in standard salts used for sample preparation and during the synthesis process can alter the physical and chemical behavior of the pure and doped nano-materials. Therefore, it becomes important to determine concentration of various elements present in synthesized nano-material sample. In present work, the elemental and compositional analysis of nano-materials synthesized using various methods has been performed using photon-atom interaction based energy dispersive x-ray fluorescence (EDXRF) technique. This technique due to its multielement analytical capability, lower detection limit, capability to analyze metals and non-metals alike and almost no sample preparation requirements can be utilized for analysis of nano-materials. The EDXRF spectrometer involves a 2.4 kW Mo anode x-ray tube (Pananalytic, Netherland) equipped with selective absorbers as an excitation source and an LEGe detector (FWHM = 150 eV at 5.895 keV, Canberra, US) coupled with PC based multichannel analyzer used to collect the fluorescent x-ray spectra. The analytical results showed good agreements with the expected values calculated on the basis of the precursor used in preparation of nano-materials