Institutional Factors behind Effectiveness of Irrigation: A Study in the Brahmaputra Valley in Eastern India

As the adverse consequences of the policies of input subsidy and increasing food-grain procurement prices became prominent in Indian agriculture, researchers and policy makers documented the need for policy changes. For sustaining production of rice, there are now calls for shift of emphasis from large farmers in Green Revolution areas in Northwest India to small and marginal farmers in Eastern and rain-fed areas, where returns to both labor and capital are high and potentials for exploiting the existing technology are yet largely untapped. A major constraint on exploiting such potentials in parts of Eastern India such as the Brahmaputra Valley is paucity of irrigation. While investment for expanding irrigation capacity is needed, it is equally important to put necessary institutions in place to ensure that the installed capacity is effectively utilized. This study based on survey of 172 farms from three agro-climatic zones of the Brahmaputra Valley has found that farmers control over management and operation of irrigation system is crucial in determining their success in effectively using irrigation in terms of level and intensity of productivity increasing practices associated with irrigation. The study hence suggests that to improve effectiveness, and thereby reap higher social returns on public investment on irrigation, involvement of farmers in operation and management of public sector irrigation systems should be secured. In view of the effectiveness of small-scale private tube-wells and the abundance of ground water reserves in the Brahmaputra valley, facilitation of private investments in such sys tems is recommended for expanding total irrigation capacity.Effectiveness of irrigation, institutions, stake holding farmers, regulations, Brahmaputra Valley, Institutional and Behavioral Economics, Resource /Energy Economics and Policy,

Non-equilibrium phonon dynamics in trapped ion systems

We propose a concrete experiment to probe the non-equilibrium local dynamics of the one-dimensional Bose-Hubbard model using a trapped ion system consisting of a linear chain of few Ba^+ ions prepared in a state of transverse motional mode which corresponds to a fixed number of phonons per ion. These phonons are well-known to be described by an effective Bose-Hubbard model. We propose a protocol which leads to a sudden local sign reversal of the on-site interaction strength of this Hubbard model at one of the sites and demonstrate that the subsequent non-equilibrium dynamics of the model can be experimentally probed by measuring the time-dependent phonon number in a specific motional state of the Ba+ ions. We back our experimental proposal with exact numerical calculation of the dynamics of a Bose-Hubbard model subsequent to a local quench.Comment: The submission contains 5 pages and 4 figure

Orbital physics of polar Fermi molecules

We study a system of polar dipolar fermions in a two-dimensional optical lattice and show that multi-band Fermi-Hubbard model is necessary to discuss such system. By taking into account both on-site, and long-range interactions between different bands, as well as occupation-dependent inter- and intra-band tunneling, we predict appearance of novel phases in the strongly-interacting limit

Color Transparency: past, present and future

We review a unique prediction of Quantum Chromo Dynamics, called color transparency (CT), where the final (and/or initial) state interactions of hadrons with the nuclear medium must vanish for exclusive processes at high momentum transfers. We retrace the progress of our understanding of this phenomenon, which began with the discovery of the $J/\psi$ meson, followed by the discovery of high energy CT phenomena, the recent developments in the investigations of the onset of CT at intermediate energies and the directions for future studies.Comment: 41 pages, 27 figures, to appear in Prog. Nucl. Part. Phy

Tribrid Inflation in Supergravity

We propose a novel class of F-term hybrid inflation models in supergravity (SUGRA) where the $\eta$-problem is resolved using either a Heisenberg symmetry or a shift symmetry of the Kaehler potential. In addition to the inflaton and the waterfall field, this class (referred to as tribrid inflation) contains a third 'driving' field which contributes the large vacuum energy during inflation by its F-term. In contrast to the ''standard'' hybrid scenario, it has several attractive features due to the property of vanishing inflationary superpotential (W_inf=0) during inflation. While the symmetries of the Kaehler potential ensure a flat inflaton potential at tree-level, quantum corrections induced by symmetry breaking terms in the superpotential generate a slope of the potential and lead to a spectral tilt consistent with recent WMAP observations.Comment: To appear in the proceedings of SUSY09; 5 page

Effect of processing on fracture toughness of silicon carbide as determined by Vickers indentations

Several alpha-SiC materials were processed by hot isostatic pressing (HIPing) and by sintering an alpha-SiC powder containing boron and carbon. Several beta-SiC materials were processed by HIPing a beta-SiC powder with boron and carbon additions. The fracture toughnesses K(sub 1c) of these beta- and alpha-SiC materials were estimated from measurements of Vickers indentations. The three formulas used to estimate K(sub 1c) from the indentation fracture patterns resulted in three ranges of K(sub 1c) estimates. Furthermore, each formula measured the effects of processing differently. All three estimates indicated that fine-grained HIPed alpha-SiC has a higher K(sub 1c) than coarsed-grained sintered alpha-SiC. Hot isostatically pressed beta-SiC, which had an ultrafine grain structure, exhibited a K(sub 1c) comparable to that of HIPed alpha-SiC