Recovery of chromite values from tailings of COB plant using enhanced gravity concentrator

In world scenario, India is ranked third largest producer of chromite ore. Odisha Mining Corporation Ltd. is operating a chromite ore beneficiation (COB) plant with a capacity of 0.15 mtpa. The process route basically involves comminution, classification followed by gravity separation. The present plant practice generates tailings with some chromite values associated with it. In the present study, an attempt was made to recover chromite values from the tailings using enhanced gravity separator such as Falcon concentrator, a high g-force generating equipment. The tailing sample is very fine grained in nature and contains significant amount (~68 Wt.%) of particle below 11 μm. The chemical analysis of head sample shows a value of 20.23% Cr2O3. Mineralogical study revealed that chromite is the major chromite bearing mineral and clay, gibbsite and spinel are the major gangue minerals present in the material. The process parameters are optimised with respect to feed particle size, bowl rotation speed and the back water flow rate. It was observed that high rotation of the bowl and high back water flow rate favour generating a clean concentrate with Cr2O3 more than 40% with >68% recovery

Artery tertiary lymphoid organs control aorta immunity and protect against atherosclerosis via vascular smooth muscle cell lymphotoxin β receptors

Tertiary lymphoid organs (TLOs) emerge during nonresolving peripheral inflammation, but their impact on disease progression remains unknown. We have found in aged Apoe−/− mice that artery TLOs (ATLOs) controlled highly territorialized aorta T cell responses. ATLOs promoted T cell recruitment, primed CD4+ T cells, generated CD4+, CD8+, T regulatory (Treg) effector and central memory cells, converted naive CD4+ T cells into induced Treg cells, and presented antigen by an unusual set of dendritic cells and B cells. Meanwhile, vascular smooth muscle cell lymphotoxin β receptors (VSMC-LTβRs) protected against atherosclerosis by maintaining structure, cellularity, and size of ATLOs though VSMC-LTβRs did not affect secondary lymphoid organs: Atherosclerosis was markedly exacerbated in Apoe−/−Ltbr−/− and to a similar extent in aged Apoe−/−Ltbrfl/flTagln-cre mice. These data support the conclusion that the immune system employs ATLOs to organize aorta T cell homeostasis during aging and that VSMC-LTβRs participate in atherosclerosis protection via ATLOs

Constraints on Astro-unparticle Physics from SN 1987A

SN 1987A observations have been used to place constraints on the interactions between standard model particles and unparticles. In this study we calculate the energy loss from the supernovae core through scalar, pseudo scalar, vector, pseudo vector unparticle emission from nuclear bremsstrahlung for degenerate nuclear matter interacting through one pion exchange. In order to examine the constraints on $d_{\cal U}=1$ we considered the emission of scalar, pseudo scalar, vector, pseudo vector and tensor through the pair annihilation process $e^+e^-\to {\cal U} \gamma$. In addition we have re-examined other pair annihilation processes. The most stringent bounds on the dimensionless coupling constants for $d_{\cal U} =1$ and $\Lambda_{\cal U}= m_Z$ are obtained from nuclear bremsstrahlung process for the pseudo scalar and pseudo-vector couplings $\bigl|\lambda^{\cal P}_{0,1}\bigr|\leq 4\times 10^{-11}$ and for tensor interaction, the best limit on dimensionless coupling is obtained from $e^+ e^-\to {\cal U} \gamma$ and we get $\bigl|\lambda^{\cal T}\bigr| \leq 6\times 10^{-6}$.Comment: 12 pages, 2 postscript figure

Constraints from Solar and Reactor Neutrinos on Unparticle Long-Range Forces

We have investigated the impact of long-range forces induced by unparticle operators of scalar, vector and tensor nature coupled to fermions in the interpretation of solar neutrinos and KamLAND data. If the unparticle couplings to the neutrinos are mildly non-universal, such long-range forces will not factorize out in the neutrino flavour evolution. As a consequence large deviations from the observed standard matter-induced oscillation pattern for solar neutrinos would be generated. In this case, severe limits can be set on the infrared fix point scale, Lambda_u, and the new physics scale, M, as a function of the ultraviolet (d_UV) and anomalous (d) dimension of the unparticle operator. For a scalar unparticle, for instance, assuming the non-universality of the lepton couplings to unparticles to be of the order of a few per mil we find that, for d_UV=3 and d=1.1, M is constrained to be M > O(10^9) TeV (M > O(10^10) TeV) if Lambda_u= 1 TeV (10 TeV). For given values of Lambda_u and d, the corresponding bounds on M for vector [tensor] unparticles are approximately 100 [3/Sqrt(Lambda_u/TeV)] times those for the scalar case. Conversely, these results can be translated into severe constraints on universality violation of the fermion couplings to unparticle operators with scales which can be accessible at future colliders.Comment: 13 pages, 3 figures. Minor changes due to precision in numerical factors and correction in figure labels. References added. Conclusions remain unchange

Search for Higgs bosons of the Universal Extra Dimensions at the Large Hadron Collider

The Higgs sector of the Universal Extra Dimensions (UED) has a rather involved setup. With one extra space dimension, the main ingredients to the construct are the higher Kaluza-Klein (KK) excitations of the Standard Model Higgs boson and the fifth components of the gauge fields which on compactification appear as scalar degrees of freedom and can mix with the former thus leading to physical KK-Higgs states of the scenario. In this work, we explore in detail the phenomenology of such a Higgs sector of the UED with the Large Hadron Collider (LHC) in focus. We work out relevant decay branching fractions involving the KK-Higgs excitations. Possible production modes of the KK-Higgs bosons are then discussed with an emphasis on their associated production with the third generation KK-quarks and that under the cascade decays of strongly interacting UED excitations which turn out to be the only phenomenologically significant modes. It is pointed out that the collider searches of such Higgs bosons face generic hardship due to soft end-products which result from severe degeneracies in the masses of the involved excitations in the minimal version of the UED (MUED). Generic implications of either observing some or all of the KK-Higgs bosons at the LHC are discussed.Comment: 25 pages, 9 figures and 1 tabl

Two body non-leptonic Λb\Lambda_b decays in the large NcN_c limit

The two body non-leptonic $\Lambda_b$ decays are analyzed in the HQET with factorization approximation and large $N_c$ limit. In this limit, $\Lambda_b$ and $\Lambda_c$ baryons can be treated as the bound states of chiral soliton and heavy meson, and consequently the Isgur-Wise function comes out in a straight forward manner. The results obtained remain well below their previously predicted upper limit

New Physics in Bs -> J/psi phi: a General Analysis

Recently, the CDF and D0 collaborations measured indirect CP violation in Bs -> J/psi phi and found a hint of a signal. If taken at face value, this can be interpreted as a nonzero phase of Bs-Bsbar mixing (beta_s), in disagreement with the standard model, which predicts that beta_s ~= 0. In this paper, we argue that this analysis may be incomplete. In particular, there can be new physics (NP) in the bbar -> sbar c cbar decay. If so, the value of beta_s is different than for the case in which NP is assumed to be present only in the mixing. We have examined several models of NP and found that, indeed, there can be significant contributions to the decay. These effects are consistent with measurements in B -> J/psi K* and Bd -> J/psi Ks. Due to the NP in the decay, polarization-dependent indirect CP asymmetries and triple-product asymmetries are predicted in Bs -> J/psi phi.Comment: 28 pages, JHEP, no figures. Considerable changes made. Abstract and main text of paper modified to alter presentation. Appendix added. References added. Conclusions unchanged

Study of Bs-> \phi l^+ l^-$ Decay in a Single Universal Extra Dimension

Utilizing form factors calculated within the light-cone sum rules, we have evaluated the decay branching ratios of $B_s\to \phi\gamma$ and $B_s\to \phi \ell^+\ell^-$ in a single universal extra dimension model (UED), which is viewed as one of the alternative theories beyond the standard model (SM). For the decay $B_s \to \phi \ell^+\ell^-$, the dilepton invariant mass spectra, the forward-backward asymmetry, and double lepton polarization are also calculated. For each case, we compared the obtained results with predictions of the SM. In lower values of the compactification factor 1/R, the only parameter in this model, we see the considerable discrepancy between the UED and SM models. However, when 1/R increases, the results of UED tend to diminish and at $1/R = 1000 \mathrm{GeV}$, two models have approximately the same predictions. Compared with data from CDF of $B_s \to \phi \mu^+ \mu^-$, the 1/R tends to be larger than $350 \mathrm{GeV}$. We also note that the zero crossing point of the forward-backward asymmetry is become smaller, which will be an important plat to prob the contribution from the extra dimension model. The results obtained in this work will be very useful in searching new physics beyond SM. Moreover, the order of magnitude for branching ratios shows a possibility to study these channels at the Large Hadron Collider (LHC), CDF and the future super-B factory.Comment: 13 pages, 16 figure

Neutral Gauge Boson Contributions to the Dimuon Charge Asymmetry in B Decays

Recently, the D0 Collaboration measured the CP-violating like-sign dimuon charge asymmetry in neutral B decays, finding a 3.2sigma difference from the standard-model (SM) prediction. A non-SM charge asymmetry a_sl^s suggests a new-physics (NP) contribution to Bs-Bsbar mixing. In this case, in order to explain the measured value of a_sl^s within its 1sigma range, NP must be present in Gamma_12^s, the absorptive part of the mixing. In this paper, we examine whether such an explanation is possible in models with flavor-changing Z (ZFCNC) or Z' (Z'FCNC) gauge bosons. The models must also reproduce the measured values of the indirect CP asymmetry S_psi-phi in Bs -> J/psi phi, and Delta Gamma_s, the Bs-Bsbar width difference. We find that the ZFCNC model cannot reproduce the present measured values of S_psi-phi and a_sl^s within their 1sigma ranges. On the other hand, in the Z'FCNC model, the values of all three observables can be simultaneously reproduced.Comment: 18 pages, 7 figures, JHEP format. Some ZFCNC equations corrected, ZFCNC analysis redone, references added, conclusions unchange

Constraint on compactification scale via recently observed baryonic Λb→Λℓ+ℓ−\Lambda_b\rightarrow \Lambda \ell^+ \ell^- channel and analysis of the Σb→Σℓ+ℓ−\Sigma_b \rightarrow \Sigma \ell^+ \ell^- transition in SM and UED scenario

We obtain a lower limit on the compactification scale of extra dimension via comparison of the branching ratio in the baryonic $\Lambda_b\rightarrow \Lambda \mu^+ \mu^-$ decay channel recently measured by CDF collaboration and our previous theoretical study. We also use the newly available form factors calculated via light cone QCD sum rules in full theory to analyze the flavour changing neutral current process of the $\Sigma_b \rightarrow \Sigma \ell^+ \ell^-$ in universal extra dimension scenario in the presence of a single extra compact dimension. We calculate various physical quantities like branching ratio, forward-backward asymmetry, baryon polarizations and double lepton polarization asymmetries defining the decay channel under consideration. We also compare the obtained predictions with those of the standard model.Comment: 32 Pages, 27 Figures and one Tabl