Papers by Abhijit Samanta
We study dependence of the atmospheric $\nu_\mu$ and $\bar{\nu}_\mu$ fluxes on the deviations of ... more We study dependence of the atmospheric $\nu_\mu$ and $\bar{\nu}_\mu$ fluxes on the deviations of 2-3 mixing from maximal $|45^\circ - \theta_{23}|$, on the $\theta_{23}$-octant and on the neutrino mass split $\Delta m_{32}^2$. Analytic expressions for the effect of $\theta_{23}$ deviation and the octant asymmetry are derived. We present conservative estimations of sensitivities of iron (magnetized) calorimeter detectors (ICAL) to these
The large iron calorimeter which is a tracking detector has the ability to measure the energy and... more The large iron calorimeter which is a tracking detector has the ability to measure the energy and the direction of the muon with high resolution. From the bending of the track in magnetic field it can also distinguish its charge. We have analyzed the atmospheric neutrino oscillation for this detector generating events by Nuance and then considering the muons produced
J Phys G Nucl Particle Phys, 2003
We study the effects of SO(10) D-terms on the allowed parameter space (APS) in models with t-b-tg... more We study the effects of SO(10) D-terms on the allowed parameter space (APS) in models with t-b-tgr and b-tgr Yukawa unification. The former is allowed only for moderate values of the D-term, if very precise (les5%) unification is required. Next we constrain the parameter space by looking for different dangerous directions where the scalar potential may be unbounded from below (UFB1 and UFB3). The common trilinear coupling A0 plays a significant role in constraining the APS. For very precise t-b-tgr Yukawa unification, -m16 lap A0 lap m16 can be probed at the LHC, where m16 is the common soft breaking mass for the sfermions. Moreover, an interesting mass hierarchy with very heavy sfermions but light gauginos, which is strongly disfavoured in models without D-terms, becomes fairly common in the presence of the D-terms. The APS exhibits interesting characteristics if m16 is not the same as the soft breaking mass m10 for the Higgs sector. In b-tgr unification models with D-terms, the APS consistent with Yukawa unification and radiative electroweak symmetry breaking, increases as the UFB1 constraint becomes weaker. However, for A0 lap 0, a stronger UFB3 condition still puts, for a given m16, a stringent upper bound on the common gaugino mass (m1/2) and a lower bound on m16 for a given m1/2. The effects of sign of mgr on Yukawa unification and UFB constraints are also discussed.
ABSTRACT A detailed investigation has been made on interfacial and rheological properties of natu... more ABSTRACT A detailed investigation has been made on interfacial and rheological properties of natural guar gum polymer and surfactant obtained from extracted soap nut shell. The experimental data were analyzed to find an optimum formulation of different chemicals. With the optimum concentration of different chemical slugs, flooding experiments were performed for enhanced recovery of oil over water flooding. Experimental results show that flooding with ASP slug gives better recovery (~ 25% of original oil in place after water flooding) over simply polymer and surfactant-polymer flooding. The polymer and surfactant used in this study are environment sustainable materials and show great potential to be used in future enhanced oil recovery operations.
International Journal of Oil Gas and Coal Technology, Mar 20, 2015
Polymers are often used as mobility controller for enhanced oil recovery. The present paper deals... more Polymers are often used as mobility controller for enhanced oil recovery. The present paper deals with the application of partially hydrolysed polyacrylamide (PHPA) polymer in enhanced oil recovery after the conventional water flooding. Experimental results show that viscosity of PHPA solution increases significantly on addition of small quantity of polymer, which in turn decreases the mobility ratio. The effect of frontal-advance velocity on the total relative mobility at different concentration of polymer has been discussed. A series of flooding experiments were performed in a flooding apparatus to observe the efficiency of polymer flooding at different concentration of PHPA. The crude oil is collected from Ahmedabad oil-field, India (total acid number of 0.038 mg KOH/g, gravity of 38.86° API and viscosity of 119 mPa.s at 30°C). The additional oil recoveries vary 16% to 20% of original oil in place (OOIP) depending on the polymer concentration.
Petroleum Science and Technology, 2011
ABSTRACT Experimental studies have been performed to explore the suitability of an eco-friendly s... more ABSTRACT Experimental studies have been performed to explore the suitability of an eco-friendly surfactant in enhanced oil recovery. In this respect, herbal surfactant has been isolated from soap nut and characterized by its morphology and physico-chemical properties. The extracted surfactant reduces the interfacial tension significantly over a wide range of concentrations. A series of flooding experiments have been carried out using the extracted surfactant and substantial incremental recoveries have been observed after the conventional water flooding. Use of alkali and polymer were found to improve the incremental recovery because of synergistic effects of surfactant, polymer and alkali.
Among the combinations $L_e-L_\mu$, $L_e-L_\tau$ and $L_\mu-L_\tau$ any one can be gauged in anom... more Among the combinations $L_e-L_\mu$, $L_e-L_\tau$ and $L_\mu-L_\tau$ any one can be gauged in anomaly free way with the standard model gauge group. The masses of these gauge bosons can be so light that it can induce long-range forces on the Earth due to the electrons in the Sun. This type of forces can be constrained significantly from neutrino oscillation. As the sign of the potential is opposite for neutrinos and antineutrinos, a magnetized iron calorimeter detector (ICAL) would be able to produce strong constraint on it. We have made conservative studies of these long-range forces with atmospheric neutrinos at ICAL considering only the muons of charge current interactions. We find stringent bounds on the couplings $ \alpha_{e\mu, e\tau} \lapp 1.65 \times 10^{-53}$ at 3$\sigma$ CL with an exposure of 1 Mton$\cdot$yr if there is no such force. For nonzero input values of the couplings we find that the potential $V_{e\mu}$ opposes and $V_{e\tau}$ helps to discriminate the mass hierarchy. However, both potentials help significantly to discriminate the octant of $\theta_{23}$. The explanation of the anomaly in recent MINOS data (the difference of $\Delta m^2_{32}$ for neutrinos and antineutrinos), using long-range force originated from the mixing of the gauge boson $Z^\prime$ of $L_\mu-L_\tau$ with the standard model gauge boson $Z$, can be tested at ICAL at more than 5$\sigma$ CL. We have also discussed how to disentangle this from the solution with CPT violation using the seasonal change of the distance between the Earth and the Sun.
Journal of Physics G Nuclear and Particle Physics, 2003
We study the effects of SO(10) D-terms on the allowed parameter space (APS) in models with t − b ... more We study the effects of SO(10) D-terms on the allowed parameter space (APS) in models with t − b − τ and b − τ Yukawa unifiction. The former is allowed only for moderate values of the D-term, if very precise (≤ 5%) unification is required. Next we constrain the parameter space by looking for different dangerous directions where the scalar potential may be unbounded from below (UFB1 and UFB3). The common trilinear coupling A 0 plays a significant role in constraing the APS. For very precise
Asia Pacific Journal of Chemical Engineering, 2008
Interaction between water-soluble polymers and anionic surfactants has been studied by surface te... more Interaction between water-soluble polymers and anionic surfactants has been studied by surface tension and conductivity measurements. Sodium dodecyl sulfate (SDS) and sodium dodecylbenzene sulfonate (SDBS) were used as surfactant while polyacrylamide (PAA), commercial grade partially hydrolyzed polyacrylamide (PHPA), and xanthan gum were used as water-soluble polymers for the present study. The behavior of surfactant-polymer interaction was found to be dependent on both surfactant and polymer concentrations. After the critical aggregation concentration (CAC), interaction between the water-soluble polymer and surfactants was started and above the polymer saturation point (PSP) polymer was saturated by surfactant with no further change of surface tension and conductivity of the solution. It has also been found that alkali (NaOH) and salts (Na 2 CO 3 , NaCl) have significant influence on the polymer-surfactant interaction.
Extended surfactants are amphiphiles containing a spacer arm with intermediate polarity between t... more Extended surfactants are amphiphiles containing a spacer arm with intermediate polarity between tail and head groups . This spacer arm plays the role of the so-called lipophilic linker , and seems to be a handy way to improve solubilization in microemulsions and to lower the surface or interfacial tension , particularly with long alkanes
We have explored the possibility of testing the unification of quark and lepton mixings along wit... more We have explored the possibility of testing the unification of quark and lepton mixings along with the unification of gauge couplings at LHC combined with cosmological data. We have considered the simplest supersymmetric model -minimal supergravity model. The only positive sign of µ (with conventional definition) is allowed if mν i < ∼ 1 eV. This limit on neutrino mass is strongly favored by cosmological data and the positive sign of µ is again preferred by g − 2 of muon. Very strong lower bounds on the sparticle masses are found correlated with mν i : mg > ∼ 1 TeV, mt 1 > ∼ 0.7 TeV, and mẽ L > ∼ 0.5 TeV for µ > 0 and mν i < ∼ 1 eV. All these bounds surprisingly follow the recent ATLAS results and are well above the ATLAS bounds. Then we have argued that the negative result of the search for sparticles at LHC may be a hint for quark-lepton unification and supportive for cosmological bounds. For both sign of µ the bounds are weakened when mν i increases over 1 eV.
Industrial Engineering Chemistry Research, 2010
Oil-in-water emulsions are important in the petroleum industry as a displacing fluid for enhanced... more Oil-in-water emulsions are important in the petroleum industry as a displacing fluid for enhanced oil recovery (EOR). To investigate the efficiency of oil-water emulsions in EOR, experiments were performed to characterize the emulsions in terms of their physicochemical properties and size distribution of the dispersed oil droplet in water phase. In the present study commercially available gear oil was used to prepare oil-inwater emulsions. Flooding experiments were also carried out to evaluate the effectiveness of the emulsion as displacing fluid for enhanced oil recovery. Substantial additional recoveries (more than 20% of original oil in place) over conventional water flooding were obtained in the present investigation.
In JHEP {\bf 1304}, 009 (2013) and arXiv:1303.2534 [hep-ph] the {\it reach of INO experiment} for... more In JHEP {\bf 1304}, 009 (2013) and arXiv:1303.2534 [hep-ph] the {\it reach of INO experiment} for determination of neutrino mass hierarchy and the sensitivity to both $\Delta m_{32}^2$ and $\theta_{23}$ have been reported, which are significantly underestimated and drastically different from earlier studies JHEP {\bf 1107}, 048 (2011), Phys. Rev. D {\bf 81}, 037302 (2010) and strongly dependent on the flux uncertainties. Here, we clarified that the effect on oscillation probability due to change of oscillation parameters are not considered appropriately due to improper binning of data, improper incorporation of resolutions, and rejection of high energy events $E\gapp $ 10 GeV.
The recent discovery of nonzero $\theta_{13}$ (equal to Cabbibo angle $\theta_C$ up to a factor o... more The recent discovery of nonzero $\theta_{13}$ (equal to Cabbibo angle $\theta_C$ up to a factor of $\sqrt{2}$), the masses of supersymmetric particles $\gapp$ TeV from LHC data, and the sum of three active neutrino masses $\sum_i m_{\nu_i}\lapp 1$ eV from the study of large scale structure of the universe motivate to study whether quark and lepton mixing have the same origin at the grand unification scale. We find that both results from neutrino experiments and LHC are complementary in quark-lepton unified models and a new constraint on SUSY parameters appears from electroweak symmetry breaking with a new correlation between the lower bounds on sparticle masses and the upper bound on $\sum_i m_{\nu_i}$. In addition, we find that only $\mu>0$ (which is favored by $(g-2)$ of muon) is allowed and $m_{\tilde q, \tilde \l} \gapp$ TeV if $\sum_i m_{\nu_i} \lapp 1$ eV. On the other hand, a small change in lower limit of $\theta_{13}$ from zero leads to a large increase in lower limits o...
Physics Letters B, 2010
We have studied CP T violation in neutrino oscillation considering three flavor framework with ma... more We have studied CP T violation in neutrino oscillation considering three flavor framework with matter effect. We have constructed a new way to find the oscillation probability incorporating CP T violating terms without any approximation. Then CP T violation with atmospheric neutrinos for a magnetized iron calorimeter detector considering the muons (directly measurable with high resolution) of the charge current events has been studied for zero and nonzero θ13 values. It is found that a potential bound of δb32 < ∼ 6 × 10 −24 GeV at 99% CL can be obtained with 1 Mton.year exposure of this detector; and unlike neutrino beam experiments, there is no possibility to generate 'fake' CP T violation due to matter effect with atmospheric neutrinos. The advantages of atmospheric neutrinos to discriminate CP T violation from CP violation and nonstandard interactions are also discussed.
Physics Letters B, 2009
We study the neutrino mass hierarchy at the magnetized Iron CALorimeter (ICAL) detector at India-... more We study the neutrino mass hierarchy at the magnetized Iron CALorimeter (ICAL) detector at India-based Neutrino Observatory with atmospheric neutrino events generated by the Monte Carlo event generator Nuance. We judicially choose the observables so that the possible systematic uncertainties can be reduced. The resolution as a function of both energy and zenith angle simultaneously is obtained for neutrinos and anti-neutrinos separately from thousand years un-oscillated atmospheric neutrino events at ICAL to migrate number of events from neutrino energy and zenith angle bins to muon energy and zenith angle bins. The resonance ranges in terms of directly measurable quantities like muon energy and zenith angle are found using this resolution function at different input values of θ 13 . Then, the marginalized χ 2 s are studied for different input values of θ 13 with its resonance ranges taking input data in muon energy and zenith angle bins. Finally, we find that the mass hierarchy can be explored up to a lower value of θ 13 ≈ 5 • with confidence level > 95% in this set up.
Experimental studies have been performed to explore the suitability of an eco-friendly surfactant... more Experimental studies have been performed to explore the suitability of an eco-friendly surfactant in enhanced oil recovery. In this respect, herbal surfactant has been isolated from soap nut and characterized by its morphology and physico-chemical properties. The extracted surfactant reduces the interfacial tension significantly over a wide range of concentrations. A series of flooding experiments have been carried out using the extracted surfactant and substantial incremental recoveries have been observed after the conventional water flooding. Use of alkali and polymer were found to improve the incremental recovery because of synergistic effects of surfactant, polymer and alkali.
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Papers by Abhijit Samanta