arXiv subjects

Mansi Dhuria

Publications and source records attributed to Mansi Dhuria.

24 records · Page 2Linked to original sources

arXiv2015

Explaining the CMS $eejj$ and $e\ \rm{missing}\ p_T \ jj$ excess and leptogenesis in superstring inspired $E_6$ models

We show that superstring inspired $E_6$ models can explain both the recently detected excess $eejj$ and $e\ \rm{missing}\ p_T \ jj$ signals at CMS, and also allow for leptogenesis. Working in a R-parity conserving low energy supersymmetric effective model, we show that the excess CMS events can be produced via the decay of exotic sleptons in Alternative Left-Right Symmetric Model of $E_6$, which can also accommodate leptogenesis at a high scale. On the other hand, either the $eejj$ excess or the $e\ \rm{missing}\ p_T \ jj$ excess can be produced via the decays of right handed gauge bosons, but some of these scenarios may not accommodate letptogenesis as there will be strong $B-L$ violation at low energy, which, along with the anomalous fast electroweak $B+L$ violation, will wash out all baryon asymmetry. Baryogenesis below the electroweak scale may then need to be implemented in these models.

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arXiv2015

Towards MQGP

For the Ouyang embedding we calculate the chemical potential mu_C due to a U(1) gauge field on the w.v. of N_f D7-branes wrapped around a 4-cycle in a resolved warped deformed conifold with (M)N (fractional)D3-branes of [1], and show the possible thermodynamical stability up to linear order in the embedding parameter. In the spirit of [2] we obtain the local type IIA mirror using SYZ mirror symmetry near (theta_{1,2},psi)=( ,{0,2pi,,4pi}) and then oxidize the same to M theory. We take two limits of this uplift:(i)g_s,g_sN_f,g_sM^2/N,g_s^2M N_f<<1,g_sM,g_sN>>1 similar to [1] effected by M eps^{-3d/2}, N eps^{-19d},g_s epsn^d,d>0 and eps<=O(0.01);(ii)the `MQGP limit' g_sM^2/N<<1, g_sN>>1 for finite g_s,M, effected by: g_s eps, M eps^{-3d/2},N eps^{-39d},d>0, eps<~1). The second limit is more suited for the study of QGP (See [3]) and can only be addressed in M theory. The uplift gives a black M3-brane solution whose near-horizon geometry near theta_{1,2}=0,pi-branches, preserves 1/8 SUSY. We obtain eta/s=1/4pi for the uplift and the diffusion constant for types IIB/IIA backgrounds comes out to be ~1/T, for both limits. The D=11 SUGRA action up to O(R^4,|G_4|^2) is expected to receive dominant contributions near =0,pi due to poles. Introducing a small-angle cut-off c and using the =c,(pi-c)-local uplift the specific heat from the IR-finite part of the action (c-independent) turns out to be positive indicative of the thermodynamical stability of the uplift. An ALD-gravity-type interpretation can be given to the counter-terms for(i). Its verified that the black M3-brane entropy S r_h^3 from M-theoretic thermodynamical methods and the horizon areas of types IIB/IIA/M3-brane solutions.

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arXiv2014

Topics in Supergravity Phenomenology

In the first part of the review article, we discuss the possibility of realizing "mu-split-like SUSY" scenario from a phenomenological model, which we show could be realizable locally as the large volume limit of a type IIB Swiss-Cheese Calabi-Yau orientifold involving a mobile space-time filling D3-brane localized at a nearly special Lagrangian three-cycle embedded in the "big" divisor and multiple fluxed stacks of space-time filling D7-branes wrapping the same "big" divisor. We show that the mass of one of the Higgs doublets can be produced to be of the order of 125 GeV whereas other Higgs as well as higgsino mass parameter to be very heavy- the "mu-split-like SUSY" scenario. Then we discuss the role of the heavy squarks/sleptons and the light Higgs in (i) obtaining long-lived gluinos (ii) in verifying that the NLSPs (squarks/sleptons/neutralino) decay into the LSP (gravitino) respects the BBN constraints with the lifetime of the LSP (gravitino) coming out to be of the order or larger than the age of the universe, (iii) getting gravitino relic abundance of around 0.1, and (iv) obtaining electronic EDM close to the experimental upper bounds. In second part of the review article, we obtain local M-theory uplift of Type IIB background involving non-compact (resolved) warped deformed conifold and (N) space time filling D3-branes placed on the singularity of the conifold, (M) D5-branes wrapped around compact 2-sphere, and (N_f) D7-branes wrapped around non-compact four-cycle via Strominger-Yau-Zaslow's mirror symmetry prescription and show the stability of the solution so obtained. We propose a new MQGP limit corresponding to finite-string-coupling (g_s~ 1)- large-t'Hooft-coupling regime of M-theory. Interestingly, we obtain eta/s=1/4 pi for the uplift and the diffusion constant D~1/T for types IIB/IIA backgrounds in the both limits.

hep-ph↗

arXiv2014

A Healthy Electron/Neutron EDM in D3/D7 mu-Split-Like SUSY

Within the framework of N=1 gauged supergravity, using a phenomenological model which can be obtained locally as a Swiss-Cheese Calabi-Yau string-theoretic compactification with a mobile D3-brane localized on a nearly sLag three-cycle in the Calabi-Yau and fluxed stacks of wrapped D7-branes, and which provides a natural realization of mu-Split SUSY, we show that in addition to getting a significant value of electron/neutron EDM d_{e,n}/e at two-loop level, one can obtain a sizable contribution of d_{e,n}/e even at one-loop level. We obtain d_{e}/e ~ O(10^{-29}) cm from two-loop diagrams involving heavy sfermions and a light Higgs, and d_{e}/e ~ O(10^{-32}) cm from one-loop diagram involving heavy chargino and a light Higgs. Also, d_{n}/e ~ O(10^{-33}) cm from one-loop diagram involving SM-like quarks and Higgs. Next, by considering a Barr-Zee diagram involving W bosons and Higgs, and conjecturing that the CP-violating phase can appear from a linear combination of Higgs doublet obtained in the context of mu-split SUSY, we obtain d_{e,n}/e ~ O(10^{-27}) cm at two-loop level .

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arXiv2013

(N)LSP Decays and Gravitino Dark Matter Relic Abundance in Big Divisor (nearly) SLagy D3/D7 mu-Split SUSY

Using the (nearly) Ricci-flat Swiss-Cheese metric of [1], in the context of a mobile space-time filling D3-brane restricted to a nearly special Lagrangian sub-manifold (in the large volume limit, the pull-back of the Kaehler form close to zero and the real part of the pull-back of e^{-i theta},theta=pi/2 times the nowhere-vanishing holomorphic three-form providing the volume form on the three-cycle) of the "big" divisor with (fluxed stacks of) space-time filling D7-branes also wrapping the "big" divisor (corresponding to a local minimum), we provide an explicit identification of the electron and the u-quark, as well as their SU(2)_L-singlet cousins, with fermionic super-partners of four Wilson line moduli; their superpartners turn out to be very heavy, the Higgsino-mass parameter turns out to be large, one obtains one light (with a mass of 125 GeV) and one heavy Higgs and the gluino is long lived (from a collider point of view) providing a possible realization of "mu-Split Supersymmetry". By explicitly calculating the lifetimes of decays of the co-NLSPs - the first generation squark/slepton and a neutralino - to the LSP - the gravitino - as well as gravitino decays, we verify that BBN constraints relevant to the former as well as the requirement of the latter to be (more than) the age of the universe, are satisfied. For the purpose of calculation of the gravitino relic abundance in terms of the neutralino/slepton relic abundance, we evaluate the latter by evaluating the netralino/slepton (co-)annihilation cross sections and hence show that the former satisfies the requirement for a Dark Matter candidate.

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arXiv2012

Towards Large Volume Big Divisor D3-D7 "mu-Split Supersymmetry" and Ricci-Flat Swiss-Cheese Metrics, and Dimension-Six Neutrino Mass Operators

We show that it is possible to realize a "mu-split SUSY" scenario [1] in the context of large volume limit of type IIB compactifications on Swiss-Cheese Calabi-Yau's in the presence of a mobile space-time filling D3-brane and a (stack of) D7-brane(s) wrapping the "big" divisor Sigma_B. For this, we investigate the possibility of getting one Higgs to be light while other to be heavy in addition to a heavy Higgsino mass parameter. Further, we examine the existence of long lived gluino that manifests one of the major consequences of mu-split SUSY scenario, by computing its decay width as well as lifetime corresponding to the 3-body decays of the gluino into a quark, a squark and a neutralino or Goldstino, as well as 2-body decays of the gluino into either a neutralino or a Goldstino and a gluon. Guided by the geometric Kaehler potential for Sigma_B obtained in [2] based on GLSM techniques, and the Donaldson's algorithm [3] for obtaining numerically a Ricci-flat metric, we give details of our calculation in [4] pertaining to our proposed metric for the full Swiss-Cheese Calabi-Yau, but for simplicity of calculation, close to Sigma_B, which is Ricci-flat in the large volume limit. Also, as an application of the one-loop RG flow solution for the Higgsino mass parameter, we show that the contribution to the neutrino masses at the EW scale from dimension-six operators arising from the Kaehler potential, is suppressed relative to the Weinberg-type dimension-five operators.

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