arXiv subjects

Ahmed Ali

Publications and source records attributed to Ahmed Ali.

At least 73 records · Page 4Linked to original sources

arXiv2019

Interpretation of the Narrow $J/ψp$ Peaks in $Λ_b \to J/ψp K^-$ Decay in the Compact Diquark Model

Recently, the LHCb Collaboration have updated their analysis of the resonant $J/ψp$ mass spectrum in the decay $Λ_b^0 \to J/ψp K^-$. In the combined Run~1 and Run~2 LHCb data, three peaks are observed, with the former $P_c(4450)^+$ state split into two narrow states, $P_c(4440)^+$ and $P_c(4457)^+$, having the masses $M=(4440.3\pm 1.3^{+4.1}_{-4.7})$ MeV and $M=(4457.3\pm 0.6^{+4.1}_{-1.7})$ MeV, and decay widths $Γ=(20.6\pm 4.9^{+8.7}_{-10.1})$ MeV and $Γ=(6.4\pm 2.0^{+5.7}_{-1.9})$ MeV, respectively. In addition, a third narrow peak, $P_c(4312)^+$, having the mass $M=(4311.9\pm 0.7^{+6.8}_{-0.6})$ MeV and decay width $Γ=(9.8\pm 2.7^{+3.7}_{-4.5})$ MeV is also observed. The LHCb analysis is not sensitive to broad $J/ψp$ contributions like the former $P_c(4380)^+$, implying that there could be more states present in the data. Also the spin-parity, $J^P$, assignments of the states are not yet determined. We interpret these resonances in the compact diquark model as hidden-charm diquark-diquark-antiquark baryons, having the following spin and angular momentum quantum numbers: $P_c(4312)^+ =\{\bar c [cu]_{s=1} [ud]_{s=0}; L_P=0, J^P=3/2^-\}$, the $S$-wave state, and the other two as $P$-wave states, with $P_c(4440)^+ =\{\bar c [cu]_{s=1} [ud]_{s=0}; L_P=1, J^P=3/2^+\}$ and $P_c(4457)^+ = \{\bar c [cu]_{s=1} [ud]_{s=0}; L_P=1, J^P=5/2^+ \}$. The subscripts denote the spins of the diquarks and $L_P=0,1$ is the orbital angular momentum quantum number of the pentaquark. These assignments are in accord with the heavy-quark-symmetry selection rules for $Λ_b$-baryon decays, in which the spin $S=0$ of the light diquark $[ud]_{s=0}$ is conserved. The masses of observed states can be accommodated in this framework and the two heaviest states have the positive parities as opposed to the molecular-like interpretations.

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arXiv2018

Discovery potential of stable and near-threshold doubly heavy tetraquarks at the LHC

We study the LHC discovery potential of the double-bottom tetraquarks $bb \bar u \bar d$, $bb \bar u \bar s$ and $bb \bar d \bar s$, the lightest of which having $J^P=1^+$, called $T^{\{bb\}}_{[\bar u \bar d]}$, $T^{\{bb\}}_{[\bar u \bar s]}$ and $T^{\{bb\}}_{[\bar d \bar s]}$, are expected to be stable against strong decays. Employing the Monte Carlo generators MadGraph5$\_$aMC@NLO and Pythia6, we simulate the process $pp\to \bar b b\bar b b$ and calculate the $b b$-diquark jet configurations, specified by the invariant mass interval $m_{bb} < M_{T^{\{bb\}}_{[\bar q \bar q']}} + ΔM$. Estimates of $ΔM$ from the measured product $σ(pp \to B_c^+ +X){\cal B}(B_c^+\to J/ψπ^+)$ are presented and used to to get the $b b$-diquark jet cross sections in double-bottom hadrons $σ(pp \to H_{\{bb\}} +X)$, where $H_{\{bb\}} $ represent tetraquarks and baryons. This is combined with the LHCb data on the fragmentation $b \to Λ_b$ and $b \to B$ to obtain $σ(pp\to T^{\{bb\}}_{[\bar u\bar d]} +X) = (2.4 ^{+0.9}_{-0.6})\ \text{nb} $, and about a half of this for the $T^{\{bb\}}_{[\bar{u}\bar{s}]}$ and $T^{\{bb\}}_{[\bar d \bar s]}$. We also present estimates of the production cross sections for the mixed bottom-charm tetraquarks, $bc \bar u \bar d$, $bc \bar u \bar s$ and $bc \bar d \bar s$, obtaining $σ(pp\to T^{[bc]}_{[\bar u \bar d]} +X)= (48^{+19}_{-12})\ {\rm nb}$, and the related ones having $T^{[bc]}_{[\bar u \bar s]}$ and $T^{[bc]}_{[\bar d \bar s]}$. They have excellent discovery potential at the LHC, as their branching ratios in various charge combinations of $BD_{(s)} (γ)$ are anticipated to be large.

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arXiv2018

Prospects of discovering stable double-heavy tetraquarks at a Tera-$Z$ factory

Motivated by a number of theoretical considerations, predicting the deeply bound double-heavy tetraquarks $T^{\{bb\}}_{[\bar u \bar d]}$, $T^{\{bb\}}_{[\bar u \bar s]}$ and $T^{\{bb\}}_{[\bar d \bar s]}$, we explore the potential of their discovery at Tera-$Z$ factories. Using the process $Z \to b \bar b b \bar b$, we calculate, employing the Monte Carlo generators MadGraph5$\_$aMC@NLO and Pythia6, the phase space configuration in which the~$b b$ pair is likely to fragment as a diquark. In a jet-cone, defined by an invariant mass interval $m_{bb} < M_{T^{\{bb\}}_{[\bar q \bar q']}} + ΔM$, the sought-after tetraquarks $T^{\{bb\}}_{[\bar q \bar q^\prime]}$ as well as the double-bottom baryons,~$Ξ_{bb}^{0,-}$, and $Ω_{bb}^-$, can be produced. Using the heavy quark--diquark symmetry, we estimate $\mathcal{B} (Z \to T^{\{bb\}}_{[\bar u \bar d]} + \; \bar b \bar b) = (1.4^{+1.1}_{-0.5}) \times 10^{-6}$, and about a half of this for the $T^{\{bb\}}_{[\bar{u}\bar{s}]}$ and $T^{\{bb\}}_{[\bar d \bar s]}$. We also present an estimate of their lifetimes using the heavy quark expansion, yielding $τ(T^{\{bb\}}_{[\bar q \bar q^\prime]}) \simeq 800$~fs. Measuring the tetraquark masses would require decays, such as $T^{\{bb\} -}_{[\bar u \bar d]} \to B^- D^- π^+$, $T^{\{bb\} -}_{[\bar u \bar d]} \to J/ψ\overline K^0 B^-$, $T^{\{bb\} -}_{[\bar u \bar d]} \to J/ψK^- \overline B^0$, $T^{\{bb\} -}_{[\bar u \bar s]} \to Ξ_{bc}^0 Σ^-$, and $T^{\{bb\} 0}_{[\bar d \bar s]} \to Ξ_{bc}^0 \barΣ^0$, with subsequent decay chains in exclusive non-leptonic final states. We estimate a couple of the decay widths and find that the product branching ratios do not exceed~$10^{-5}$. Hence, a good fraction of these modes will be required for a discovery of $T^{\{bb\}}_{[\bar q \bar q']}$ at a Tera-$Z$ factory.

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arXiv2018

Convolutional Neural Networks and Language Embeddings for End-to-End Dialect Recognition

Dialect identification (DID) is a special case of general language identification (LID), but a more challenging problem due to the linguistic similarity between dialects. In this paper, we propose an end-to-end DID system and a Siamese neural network to extract language embeddings. We use both acoustic and linguistic features for the DID task on the Arabic dialectal speech dataset: Multi-Genre Broadcast 3 (MGB-3). The end-to-end DID system was trained using three kinds of acoustic features: Mel-Frequency Cepstral Coefficients (MFCCs), log Mel-scale Filter Bank energies (FBANK) and spectrogram energies. We also investigated a dataset augmentation approach to achieve robust performance with limited data resources. Our linguistic feature research focused on learning similarities and dissimilarities between dialects using the Siamese network, so that we can reduce feature dimensionality as well as improve DID performance. The best system using a single feature set achieves 73% accuracy, while a fusion system using multiple features yields 78% on the MGB-3 dialect test set consisting of 5 dialects. The experimental results indicate that FBANK features achieve slightly better results than MFCCs. Dataset augmentation via speed perturbation appears to add significant robustness to the system. Although the Siamese network with language embeddings did not achieve as good a result as the end-to-end DID system, the two approaches had good synergy when combined together in a fused system.

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arXiv2017

A New Look at the $Y$ Tetraquarks and $Ω_c$ Baryons in the Diquark Model

We analyze the hidden charm $P$-wave tetraquarks in the diquark model, using an effective Hamiltonian incorporating the dominant spin-spin, spin-orbit and tensor interactions. We compare with other $P$-wave system such as $P$-wave charmonia and the newly discovered $Ω_c$ baryons, analysed recently in this framework. Given the uncertain experimental situation on the $Y$ states, we allow for different spectra and discuss the related parameters in the diquark model. In addition to the presently observed ones, we expect many more states in the supermultiplet of $L=1$ diquarkonia, whose $J^{PC}$ quantum numbers and masses are worked out, using the parameters from the currently preferred $Y$-states pattern. The existence of these new resonances would be a decisive footprint of the underlying diquark dynamics.

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arXiv2017

Speech Recognition Challenge in the Wild: Arabic MGB-3

This paper describes the Arabic MGB-3 Challenge - Arabic Speech Recognition in the Wild. Unlike last year's Arabic MGB-2 Challenge, for which the recognition task was based on more than 1,200 hours broadcast TV news recordings from Aljazeera Arabic TV programs, MGB-3 emphasises dialectal Arabic using a multi-genre collection of Egyptian YouTube videos. Seven genres were used for the data collection: comedy, cooking, family/kids, fashion, drama, sports, and science (TEDx). A total of 16 hours of videos, split evenly across the different genres, were divided into adaptation, development and evaluation data sets. The Arabic MGB-Challenge comprised two tasks: A) Speech transcription, evaluated on the MGB-3 test set, along with the 10 hour MGB-2 test set to report progress on the MGB-2 evaluation; B) Arabic dialect identification, introduced this year in order to distinguish between four major Arabic dialects - Egyptian, Levantine, North African, Gulf, as well as Modern Standard Arabic. Two hours of audio per dialect were released for development and a further two hours were used for evaluation. For dialect identification, both lexical features and i-vector bottleneck features were shared with participants in addition to the raw audio recordings. Overall, thirteen teams submitted ten systems to the challenge. We outline the approaches adopted in each system, and summarise the evaluation results.

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arXiv2017

WERd: Using Social Text Spelling Variants for Evaluating Dialectal Speech Recognition

We study the problem of evaluating automatic speech recognition (ASR) systems that target dialectal speech input. A major challenge in this case is that the orthography of dialects is typically not standardized. From an ASR evaluation perspective, this means that there is no clear gold standard for the expected output, and several possible outputs could be considered correct according to different human annotators, which makes standard word error rate (WER) inadequate as an evaluation metric. Such a situation is typical for machine translation (MT), and thus we borrow ideas from an MT evaluation metric, namely TERp, an extension of translation error rate which is closely-related to WER. In particular, in the process of comparing a hypothesis to a reference, we make use of spelling variants for words and phrases, which we mine from Twitter in an unsupervised fashion. Our experiments with evaluating ASR output for Egyptian Arabic, and further manual analysis, show that the resulting WERd (i.e., WER for dialects) metric, a variant of TERp, is more adequate than WER for evaluating dialectal ASR.

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arXiv2017

MIT-QCRI Arabic Dialect Identification System for the 2017 Multi-Genre Broadcast Challenge

In order to successfully annotate the Arabic speech con- tent found in open-domain media broadcasts, it is essential to be able to process a diverse set of Arabic dialects. For the 2017 Multi-Genre Broadcast challenge (MGB-3) there were two possible tasks: Arabic speech recognition, and Arabic Dialect Identification (ADI). In this paper, we describe our efforts to create an ADI system for the MGB-3 challenge, with the goal of distinguishing amongst four major Arabic dialects, as well as Modern Standard Arabic. Our research fo- cused on dialect variability and domain mismatches between the training and test domain. In order to achieve a robust ADI system, we explored both Siamese neural network models to learn similarity and dissimilarities among Arabic dialects, as well as i-vector post-processing to adapt domain mismatches. Both Acoustic and linguistic features were used for the final MGB-3 submissions, with the best primary system achieving 75% accuracy on the official 10hr test set.

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arXiv2017

Exotics: Heavy Pentaquarks and Tetraquarks

For many decades after the invention of the quark model in 1964 there was no evidence that hadrons are formed from anything other than the simplest pairings of quarks and antiquarks, mesons being formed of a quark-antiquark pair and baryons from three quarks. In the last decade, however, in an explosion of data from both $e^+e^-$ and hadron colliders, there are many recently observed states that do not fit into this picture. These new particles are called generically "exotics". They can be either mesons or baryons. Remarkably, they all decay into at least one meson formed of either a $c\overline{c}$ or $b\overline{b}$ pair. In this review, after the introduction, we explore each of these new discoveries in detail first from an experimental point of view, then subsequently give a theoretical discussion. These exotics can be explained if the new mesons contain two-quarks and two-antiquarks (tetraquarks), while the baryons contain four-quarks plus an antiquark (pentquarks). The theoretical explanations for these states take three divergent tracks: tightly bound objects, just as in the case of normal hadrons, but with more constituents, or loosely bound "molecules" similar to the deuteron, but formed from two mesons, or a meson or baryon, or more wistfully, they are not multiquark states but appear due to kinematic effects caused by different rescatterings of virtual particles; most of these models have all been post-dictions. Both the tightly and loosely bound models predict the masses and related quantum numbers of new, as yet undiscovered states. Thus, future experimental discoveries are needed along with theoretical advances to elucidate the structure of these new exotic states.

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arXiv2017

Mass spectrum of spin-1/2 pentaquarks with a $c\bar{c}$ component and their anticipated discovery modes in $b$-baryon decays

The LHCb discovery of the two baryonic states $P_c^+(4380)$ and $P_c^+(4450)$, having $J^{P}=3/2^-$ and $J^{P}=5/2^+$, respectively, in the process $pp \to b \bar{b} \to Λ_b X$, followed by the decay $Λ_b \to J/ψ\; p\; K^-$, has motivated a number of theoretical models. Interpreting them as compact $\{\bar{c}\; [c u] \; [ud]; L_{\mathcal{P}}=0,1\}$ objects, the mass spectroscopy of the $J^P=3/2^-$ and $J^P=5/2^+$ pentaquarks was worked out by us for the pentaquarks in the $SU(3)_F$ multiplets, using an effective Hamiltonian based on constituent diquarks and quarks. Their possible discovery modes in $b$-baryon decays were also given using the heavy quark spin symmetry. In this paper, we calculate the mass spectrum of the hidden $c\bar{c}$ pentaquarks having $J^{P}=\frac{1}{2}^\pm$ for the $SU(3)_F$ multiplets and their anticipated discovery modes in $b$-baryon decays. Some of the $P_c^+(J^P=1/2^\pm$) pentaquarks, produced in the $Λ_{b}$ decays may have their masses just below the $J/ψ\, p$ threshold, in which case they should be searched for in the modes $ P_c^+(J^P=1/2^\pm) \to η_c\; p,\;\; μ^+ μ^- \;p,\;\; e^+ e^-\; p$.

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arXiv2016

Multi-view Dimensionality Reduction for Dialect Identification of Arabic Broadcast Speech

In this work, we present a new Vector Space Model (VSM) of speech utterances for the task of spoken dialect identification. Generally, DID systems are built using two sets of features that are extracted from speech utterances; acoustic and phonetic. The acoustic and phonetic features are used to form vector representations of speech utterances in an attempt to encode information about the spoken dialects. The Phonotactic and Acoustic VSMs, thus formed, are used for the task of DID. The aim of this paper is to construct a single VSM that encodes information about spoken dialects from both the Phonotactic and Acoustic VSMs. Given the two views of the data, we make use of a well known multi-view dimensionality reduction technique known as Canonical Correlation Analysis (CCA), to form a single vector representation for each speech utterance that encodes dialect specific discriminative information from both the phonetic and acoustic representations. We refer to this approach as feature space combination approach and show that our CCA based feature vector representation performs better on the Arabic DID task than the phonetic and acoustic feature representations used alone. We also present the feature space combination approach as a viable alternative to the model based combination approach, where two DID systems are built using the two VSMs (Phonotactic and Acoustic) and the final prediction score is the output score combination from the two systems.

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arXiv2016

Automatic Dialect Detection in Arabic Broadcast Speech

We investigate different approaches for dialect identification in Arabic broadcast speech, using phonetic, lexical features obtained from a speech recognition system, and acoustic features using the i-vector framework. We studied both generative and discriminate classifiers, and we combined these features using a multi-class Support Vector Machine (SVM). We validated our results on an Arabic/English language identification task, with an accuracy of 100%. We used these features in a binary classifier to discriminate between Modern Standard Arabic (MSA) and Dialectal Arabic, with an accuracy of 100%. We further report results using the proposed method to discriminate between the five most widely used dialects of Arabic: namely Egyptian, Gulf, Levantine, North African, and MSA, with an accuracy of 52%. We discuss dialect identification errors in the context of dialect code-switching between Dialectal Arabic and MSA, and compare the error pattern between manually labeled data, and the output from our classifier. We also release the train and test data as standard corpus for dialect identification.

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arXiv2016

Rare B-Meson Decays at the Crossroads

Experimental era of rare $B$-decays started with the measurement of $B \to K^* γ$ by CLEO in 1993, followed two years later by the measurement of the inclusive decay $B \to X_s γ$, which serves as the standard candle in this field. The frontier has moved in the meanwhile to the experiments at the LHC, in particular, LHCb, with the decay $B^0 \to μ^+ μ^-$ at about 1 part in $10^{10}$ being the smallest branching fraction measured so far. Experimental precision achieved in this area has put the standard model to unprecedented stringent tests and more are in the offing in the near future. I review some key measurements in radiative, semileptonic and leptonic rare $B$-decays, contrast them with their estimates in the SM, and focus on several mismatches reported recently. They are too numerous to be ignored, yet , standing alone, none of them is significant enough to warrant the breakdown of the SM. Rare $B$-decays find themselves at the crossroads, possibly pointing to new horizons, but quite likely requiring an improved theoretical description in the context of the SM. An independent precision experiment such as Belle II may help greatly in clearing some of the current experimental issues.

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arXiv2016

Heavy quark symmetry and weak decays of the $b$-baryons in pentaquarks with a $c\bar{c}$ component

The discovery of the baryonic states $P_c^+(4380)$ and $P_c^+(4450)$ by the LHCb collaboration has evoked a lot of theoretical interest. These states have the minimal quark content $c \bar{c} u u d$. Interpreted as hidden charm diquark-diquark-antiquark baryons, the assigned spin and angular momentum quantum numbers are $P_c^+(4380)= \{\bar{c} [cu]_{s=1} [ud]_{s=1}; L_{\mathcal{P}}=0, J^{\rm P}=\frac{3}{2}^- \}$ and $P_c^+(4450)= \{\bar{c} [cu]_{s=1} [ud]_{s=0}; L_{\mathcal{P}}=1, J^{\rm P}=\frac{5}{2}^+ \}$, where $s=0,1$ are the spins of the diquarks and $L_{\mathcal{P}}=0,1$ are the orbital angular momentum quantum numbers of the pentaquarks. We point out that heavy quark symmetry allows only the higher mass pentaquark state $P_c^+(4450)$ having $[ud]_{s=0}$ to be produced in $Λ_b^0$ decays, whereas the lower mass state $P_c^+(4380)$ having $[ud]_{s=1}$ is disfavored. Pentaquark spectrum is rich enough to accommodate a $J^P=\frac{3}{2}^-$ state, which has the correct light diquark spin $\{\bar{c} [cu]_{s=1} [ud]_{s=0}; L_{\mathcal{P}}=0, J^{\rm P}=\frac{3}{2}^- \}$ to be produced in $Λ_b^0$ decays. Assuming that the orbital mass difference between the charmed pentaquarks is similar to the corresponding mass difference in the charmed baryons, we estimate the mass of the lower pentaquark $J^P=3/2^-$ state to be about 4110 MeV and suggest to reanalyze the LHCb data to search for this third state. We present the spectroscopy of the $S$- and $P$-wave pentaquark states having a $c\bar{c}$ pair and three light quarks using an effective Hamiltonian approach. Some of these pentaquarks can be produced in weak decays of the $b$-baryons. Combining heavy quark symmetry and the $SU(3)_F$ symmetry results in strikingly simple relations among the decay amplitudes which are presented here.

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arXiv2016

Multiquark Hadrons - A New Facet of QCD

I review some selected aspects of the phenomenology of multiquark states discovered in high energy experiments. They have four valence quarks (called tetraquarks) and two of them are found to have five valence quarks (called pentaquarks), extending the conventional hadron spectrum which consists of quark-antiquark $(q\bar{q})$ mesons and $qqq$ baryons. Multiquark states represent a new facet of QCD and their dynamics is both challenging and currently poorly understood. I discuss various approaches put forward to accommodate them, with emphasis on the diquark model.

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arXiv2015

Improved Estimates of The $B_{(s)}\to V V$ Decays in Perturbative QCD Approach

We reexamine the branching ratios, $CP$-asymmetries, and other observables in a large number of $B_q\to VV(q=u,d,s)$ decays in the perturbative QCD (PQCD) approach, where $V$ denotes a light vector meson $(ρ, K^*, ω, ϕ)$. The essential difference between this work and the earlier similar works is of parametric origin and in the estimates of the power corrections related to the ratio $r_i^2=m_{V_i}^2/m_B^2(i=2,3)$ ($m_V$ and $m_B$ denote the masses of the vector and $B$ meson, respectively). In particular, we use up-to-date distribution amplitudes for the final state mesons and keep the terms proportional to the ratio $r_i^2$ in our calculations. Our updated calculations are in agreement with the experimental data, except for a limited number of decays which we discuss. We emphasize that the penguin annihilation and the hard-scattering emission contributions are essential to understand the polarization anomaly, such as in the $B\to ϕK^*$ and $B_s \to ϕϕ$ decay modes. We also compare our results with those obtained in the QCD factorization (QCDF) approach and comment on the similarities and differences, which can be used to discriminate between these approaches in future experiments.

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arXiv2014

Precise Calculation of the Dilepton Invariant-Mass Spectrum and the Decay Rate in $B^\pm \to π^\pm μ^+ μ^-$ in the SM

We present a precise calculation of the dilepton invariant-mass spectrum and the decay rate for $B^\pm \to π^\pm \ell^+ \ell^-$ ($\ell^\pm = e^\pm, μ^\pm $) in the Standard Model (SM) based on the effective Hamiltonian approach for the $b \to d \ell^+ \ell^-$ transitions. With the Wilson coefficients already known in the next-to-next-to-leading logarithmic (NNLL) accuracy, the remaining theoretical uncertainty in the short-distance contribution resides in the form factors $f_+ (q^2)$, $f_0 (q^2)$ and $f_T (q^2)$. Of these, $f_+ (q^2)$ is well measured in the charged-current semileptonic decays $B \to π\ell ν_\ell$ and we use the $B$-factory data to parametrize it. The corresponding form factors for the $B \to K$ transitions have been calculated in the Lattice-QCD approach for large-$q^2$ and extrapolated to the entire $q^2$-region using the so-called $z$-expansion. Using an $SU(3)_F$-breaking Ansatz, we calculate the $B \to π$ tensor form factor, which is consistent with the recently reported lattice $B \to π$ analysis obtained at large~$q^2$. The prediction for the total branching fraction ${\cal B} (B^\pm \to π^\pm μ^+ μ^-) = (1.88 ^{+0.32}_{-0.21}) \times 10^{-8}$ is in good agreement with the experimental value obtained by the LHCb Collaboration. In the low $q^2$-region, heavy-quark symmetry (HQS) relates the three form factors with each other. Accounting for the leading-order symmetry-breaking effects, and using data from the charged-current process $B \to π\ell ν_\ell$ to determine $f_+ (q^2)$, we calculate the dilepton invariant-mass distribution in the low $q^2$-region in the $B^\pm \to π^\pm \ell^+ \ell^-$ decay. This provides a model-independent and precise calculation of the partial branching ratio for this decay.

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arXiv2013

Hadroproduction of $Υ(nS)$ above $B\bar B$ Thresholds and Implications for $Y_b(10890)$

Based on the non-relativistic QCD factorization scheme, we study the hadroproduction of the bottomonium states $Υ(5S)$ and $Υ(6S)$. We argue to search for them in the final states $Υ(1S,2S,3S)π^+π^-$, which are found to have anomalously large production rates at $Υ(5S)$. The enhanced rates for the dipionic transitions in the $Υ(5S)$-energy region could, besides $Υ(5S)$, be ascribed to $Y_b(10890)$, a state reported by the Belle collaboration, which may be interpreted as a tetraquark. The LHC/Tevatron measurements are capable of making a case in favor of or against the existence of $Y_b(10890)$, as demonstrated here. Dalitz analysis of the $Υ(1S,2S,3S)π^+π^-$ states from the $Υ(5S)/Y_b(10890)$ decays also impacts directly on the interpretation of the charged bottomonium-like states, $Z_b(10600)$ and $Z_b(10650)$, discovered by Belle in these puzzling decays.

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