Quantum bound states for a derivative nonlinear Schrodinger model and number theory

A derivative nonlinear Schrodinger model is shown to support localized N-body bound states for several ranges (called bands) of the coupling constant eta. The ranges of eta within each band can be completely determined using number theoretic concepts such as Farey sequences and continued fractions. For N > 2, the N-body bound states can have both positive and negative momentum. For eta > 0, bound states with positive momentum have positive binding energy, while states with negative momentum have negative binding energy.Comment: Revtex, 7 pages including 2 figures, to appear in Mod. Phys. Lett.

Handling qualities aspects of NASA YF-12 flight experience

The handling qualities of the YF-12 airplane as observed during NASA research flights over the past five years were reviewed. Aircraft behavior during takeoff, acceleration, climb, cruise, descent, and landing are discussed. Pilot comments on the various flight phases and tasks are presented. Handling qualities parameters such as period, damping, amplitude ratios, roll-yaw coupling, and flight path response sensitivity are compared to existing and proposed handling qualities criteria. The influence of the propulsion systems, stability augmentation, autopilot systems, atmospheric gusts, and temperature changes are also discussed. YF-12 experience correlates well with flying qualities criteria, except for longitudinal short period damping, where existing and proposed criteria appear to be more stringent than necessary

Accretion disc-corona and jet emission from the radio-loud narrow-line Seyfert 1 galaxy RX J1633.3+4719

We perform X-ray/ultraviolet (UV) spectral and X-ray variability studies of the radio-loud narrow-line Seyfert 1 (NLS1) galaxy RX J1633.3+4719 using XMM-Newton and Suzaku observations from 2011 and 2012. The 0.3-10 keV spectra consist of an ultrasoft component described by an accretion disc blackbody (kT_in = 39.6^{+11.2}_{-5.5} eV) and a power law due to the thermal Comptonization ({\Gamma} = 1.96^{+0.24}_{-0.31}) of the disc emission. The disc temperature inferred from the soft excess is at least a factor of 2 lower than that found for the canonical soft excess emission from radio-quiet NLS1s. The UV spectrum is described by a power law with photon index 3.05^{+0.56}_{-0.33}. The observed UV emission is too strong to arise from the accretion disc or the host galaxy, but can be attributed to a jet. The X-ray emission from RX J1633.3+4719 is variable with fractional variability amplitude $F_{\rm var}$=13.5$\pm1.0$ per cent. In contrast to radio-quiet active galactic nuclei (AGN), X-ray emission from the source becomes harder with increasing flux. The fractional rms variability increases with energy and the rms spectrum is well described by a constant disc component and a variable power-law continuum with the normalization and photon index being anticorrelated. Such spectral variability cannot be caused by variations in the absorption and must be intrinsic to the hot corona. Our finding of possible evidence for emission from the inner accretion disc, jet and hot corona from RX J1633.3+4719 in the optical to X-ray bands makes this object an ideal target to probe the disc-jet connection in AGN.Comment: 12 pages, 11 figures, 3 tables, Published in MNRA

Detection of the high energy cut-off from the Seyfert 1.5 galaxy NGC 5273

We perform the NuSTAR and Swift/XRT joint energy spectral fitting of simultaneous observations from the broad-line Seyfert 1.5 galaxy NGC 5273. When fitted with the combination of an exponential cut-off power-law and a reflection model, a high energy cut-off is detected at 143$^{+96}_{-40}$ keV with 2-sigma significance. Existence of such cut-off is also consistent with the observed Comptonizing electron temperature when fitted with a Comptonization model independently. We observe a moderate hard X-ray variability of the source over the time-scale of ~12 years using INTEGRAL/ISGRI observations in the energy range of 20-100 keV. When the hard band count rate (6-20 keV) is plotted against the soft band count rate (3-6 keV), a hard offset is observed. Our results indicate that the cut-off energy may not correlate with the coronal X-ray luminosity in a simple manner. Similarities in parameters that describe coronal properties indicate that the coronal structure of NGC 5273 may be similar to that of the broad-line radio galaxy 3C 390.3 and another galaxy MCG-5-23-16 where the coronal plasma is dominated by electrons, rather than electron-positron pairs. Therefore, the coronal cooling is equally efficient to the heating mechanism keeping the cut-off energy at low even at the low accretion rate.Comment: 11 pages, 6 figures, 1 table, accepted for publication in MNRA

Pseudo-hermitian interaction between an oscillator and a spin half particle in the external magnetic field

We consider a spin half particle in the external magnetic field which couples to a harmonic oscillator through some pseudo-hermitian interaction. We find that the energy eigenvalues for this system are real even though the interaction is not PT invariant.Comment: Latex, no figs, 8 pages. (To appear in Mod. Phys. Lett. A

Study on yield potentiality and spatial requirement of rice varieties (Oryza sativa L.) in system of rice intensification (SRI) under red and laterite zone of West Bengal, India

Field experiment was conducted at Rice Research Station, Bankura during kharif season 2009 and 2010 to study the yield potentiality and spatial requirement of rice varieties in system of rice intensification (SRI) under red and laterite zone of West Bengal. The experiment was laid out in a randomized complete block design (RCBD) in a three replications with two rice varieties (Swarna and Lalat). Performances of swarna and lalat varieties in SRI as compared to conventional method of rice cultivation (CMRC) were investigated. Swarna (MTU 7029) has yielded maximum grain yield (6.07, 5.66 and 5.86 t ha-1 during 2009, 2010 and in pooled, respectively) from the treatment T7 (25 × 25 cm spacing) under SRI. Lowest grain yield (3.55, 3.23 and 3.38 t ha-1 during 2009, 2010 and in pooled, respectively) was recorded from treatment T9 (Lalat at 20 × 15 cm spacing) under CMRC. SRI technology has potential in increasing more grain yield, it saves seed requirement and irrigation water and chemical fertilizer considering than conventional method of cultivation. Rice cultivation is more sustainable and profitable for the farmers in SRI under the red and laterite zone of West Bengal

Effect of different sources of organic matter on the yield of rice and soil health in red and lateritic zone of West Bengal, India

Field experiment was conducted to study effect of different sources of organic matter on the yield of rice and soil at Rice Research Station, Bankura, West Bengal, India during kharif season of 2009, 2010 and 2011. Average of three years data revealed that inclusion of vermi-compost in the fertilizers schedule of rice cultivation [variety: Swarna (MTU 7029)] increased the grain yield (30.26%) as well as straw yield (32.70%). However higher pH was observed in treatments receiving paddy straw application and organic carbon (%) was also higher in the respective plots where vermi-compost and paddy straw was applied. Regarding available P2O5, there was an increasing trend up to 13-20 kg ha-1 in vermi-compost and green manure applied plots. In case of available K2O, there was a decrease value in all treatments were observed. So there was a positive balance of P and negative balance of K

Yield of aerobic rice affected by high temperature stress during summer season -A study from red and laterite zone of West Bengal, India

Field experiment on the performance of aerobic direct seeded rice (ADSR) under red and laterite zone of West Bengal was conducted at Rice Research Station, Bankura, West Bengal, India during summer season, 2012. The experimental soil was sandy loam with acidic in nature (pH: 5.2). The results exhibited that the grain yield (1 t ha-1) of rice in aerobic situation was low. This might be due to high atmospheric temperature during flowering period, which results in poor grain setting in panicle and most of them became chaffy due to spikelet sterility. Ultimately, it produced low grain yield of rice in aerobic situation during summer season due to high temperature at flowering period, grain formation and grain ripening stages. Thus, aerobic rice system of cultivation needed good management practices

On Matrix Product States for Periodic Boundary Conditions

The possibility of a matrix product representation for eigenstates with energy and momentum zero of a general m-state quantum spin Hamiltonian with nearest neighbour interaction and periodic boundary condition is considered. The quadratic algebra used for this representation is generated by 2m operators which fulfil m^2 quadratic relations and is endowed with a trace. It is shown that {\em not} every eigenstate with energy and momentum zero can be written as matrix product state. An explicit counter-example is given. This is in contrast to the case of open boundary conditions where every zero energy eigenstate can be written as a matrix product state using a Fock-like representation of the same quadratic algebra.Comment: 7 pages, late

Discrepancy between sub-critical and fast rupture roughness: a cumulant analysis

We study the roughness of a crack interface in a sheet of paper. We distinguish between slow (sub-critical) and fast crack growth regimes. We show that the fracture roughness is different in the two regimes using a new method based on a multifractal formalism recently developed in the turbulence literature. Deviations from monofractality also appear to be different in both regimes