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The Chitwan Valley is one of the largest Dun Valleys in the Himalayan foothills of Nepal. Dun gravels perhaps deposited in the late Pleistocene to very early Holocene about 22,000-7000 yr. B.P. Chitwan Dun Valley is underlain by Dun fan gravels or Dun gravels which form unconfined to semiconfined or leaky confined aquifers. The study area, situated in the NW part of the valley occupies an area of 70.8 km2.The hydrogeological situation in the study area is inferred from drilling data of Ground Water Resources Development Board (GWRDB), Agriculture Development Project Janakpur (ADPJ) and several private drilling companies .The Chitwan Dun Valley constitutes a closed groundwater system in the Siwalik Zone of Nepal Himalaya. The study area reveals the existence of two definite groundwater sub-basin each having its own hydraulic system and is a part of single large regional groundwater basin. Annual potential evapotranspiration (PET) calculated at Rampur (station no 0902) for five-year period (1990-1995) is 1.68 mm/day. Annual precipitation data recorded at Rampur is 2214 mm. Area of recharge is 70.8 km2 and estimation of total groundwater storage(reserve) is 87.31 MCM per year, and dynamic reserve or annual potential recharge is estimated as 48.60 MCM per year.   doi: 10.3126/bdg.v12i0.2249 Bulletin of the Department of Geology, Vol. 12, 2009, pp. 43-54

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This research work was carried out to analyze the X-ray flares in Blazar Mkn 421 using data from XMM-Newton observation (Observation ID: 0658801301) that lasted for 8 hours. EPIC/pn data was used for statistical analysis of the light and spectrum curve in energy ranges from 0.3 to 10.0 keV. The best fit model for the spectrum was found to be the additive model (log-parabola + black-body). The measured integrated flux in the energy range of 0.3-2 keV is  5.015x10-10 ergs cm-2 s-1 with an associated uncertainty range of (5.010 – 5.020) x 10-10 ergs cm-2 s-1 at a 90% confidence level. Similarly, the measured integrated flux in the energy range of 2-10 keV is 2.398 x  10-10 ergs cm-2 s-1 with an associated uncertainty range of (2.392 – 2.405) x  10-10 ergs cm-2 s-1 at a 90% confidence level. The fractional variability of 0.444 is relatively high, which indicates that the source is variable. The fall in count per second per energy around 2 keV in the spectrum curve suggests that the intensity of X-rays decreases in a power law manner after a strong flare at this energy. The count-rate distribution of the observation analyzed is best described by a normal distribution which suggests that the emission mechanism in the blazar is governed by additive processes.

Diffraction phenomenon occurs when the wavelength of the wave is comparable to the size of the obstacle. Tunneling through a barrier occurs when the particle size is comparable to the width of the barrier. The Transmission probability versus potential energy curve is hyperbolic in nature. This main aim of this article is to show that there is no probability of penetrating the particle through the barrier if barrier width is extremely larger and extremely smaller than the particle size. The condition for tunneling is similar to the necessary and sufficient condition for diffraction to occur. The various examples presented here shows that the penetration of the particle through the barrier is only possible when the size of the particle is comparable to the size of the barrier height. This article shows that probability occurrence, Wave-particle duality and uncertainty of a particle exists only when there is comparable size between the particle and its barrier width.