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Creators/Authors contains: "Forsgren, Nicole"

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  1. Full-duplex (FD)wireless communication, the simultaneoustransmissionandreceptionofwirelesssignalsonthesamefrequencychannel,has garneredsignificant attentionfromtheresearch community over the past decade. Softwaredefined radio (SDR) has become instrumental inbridgingthegapfromtheorytoimplementation,providingtheflexibilitynecessarytodesign anddeployFDradionodes, links,andnetworks. AspartoftheFull-DuplexWireless:FromIntegratedCircuitstoNetworks(FlexICoN)project, wehavedevelopedthreegenerationsofIC-based FDradiosthatutilizeGNURadioastheprimary controlandsignalprocessingplatform.Thispaperpresentsanoverviewof thedesignconsiderationsandtechniquesforimplementingFDin GNURadio,fromthetransmitandreceivesignal processingchainstobroadertestbedintegration. 
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  2. We use the method of characteristic sets with respect to two term orderings to prove the existence and obtain a method of computation of a bivariate dimension polynomial associated with a non-reflexive difference-differential ideal in the algebra of difference-differential polynomials with several basic derivations and one translation. As a consequence, we obtain a new proof and a method of computation of the dimension polynomial of a non-reflexive prime difference ideal in the algebra of difference polynomials over an ordinary difference field. We also discuss applications of our results to systems of algebraic difference-differential equations. 
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  3. Multivariate dimension polynomials associated with finitely generated differential and difference field extensions arise as natural generalizations of the univariate differential and difference dimension polynomials. It turns out, however, that they carry more information about the corresponding extensions than their univariate counterparts. We extend the known results on multivariate dimension polynomials to the case of difference-differential field extensions with arbitrary partitions of sets of basic operators. We also describe some properties of multivariate dimension polynomials and their invariants. 
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  4. We present a difference algebraic technique for the evaluation of the Einstein's strength of quasi-linear partial difference equations and some systems of such equations. Our approach is based on the properties of difference dimension polynomials that express the Einstein's strength and on the characteristic set method for computing such polynomials. The obtained results are applied to the comparative analysis of difference schemes for some chemical reaction-diffusion equations. 
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  5. We consider Hilbert-type functions associated with finitely generated inversive difference field extensions and systems of algebraic difference equations in the case when the translations are assigned positive integer weights. We prove that such functions are quasi-polynomials that can be represented as alternating sums of Ehrhart quasi-polynomials of rational conic polytopes. In particular, we generalize the author's results on difference dimension polynomials and their invariants to the case of inversive difference fields with weighted basic automorphisms. 
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  6. Abstract Despite the f0(980) hadron having been discovered half a century ago, the question about its quark content has not been settled: it might be an ordinary quark-antiquark ($${{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ ) meson, a tetraquark ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ q q ¯ ) exotic state, a kaon-antikaon ($${{\rm{K}}}\overline{{{\rm{K}}}}$$ K K ¯ ) molecule, or a quark-antiquark-gluon ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{g}}}$$ q q ¯ g ) hybrid. This paper reports strong evidence that the f0(980) state is an ordinary$${{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ meson, inferred from the scaling of elliptic anisotropies (v2) with the number of constituent quarks (nq), as empirically established using conventional hadrons in relativistic heavy ion collisions. The f0(980) state is reconstructed via its dominant decay channel f0(980) →π+π, in proton-lead collisions recorded by the CMS experiment at the LHC, and itsv2is measured as a function of transverse momentum (pT). It is found that thenq= 2 ($${{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ state) hypothesis is favored overnq= 4 ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{q}}}\overline{{{\rm{q}}}}$$ q q ¯ q q ¯ or$${{\rm{K}}}\overline{{{\rm{K}}}}$$ K K ¯ states) by 7.7, 6.3, or 3.1 standard deviations in thepT< 10, 8, or 6 GeV/cranges, respectively, and overnq= 3 ($${{\rm{q}}}\overline{{{\rm{q}}}}{{\rm{g}}}$$ q q ¯ g hybrid state) by 3.5 standard deviations in thepT< 8 GeV/crange. This result represents the first determination of the quark content of the f0(980) state, made possible by using a novel approach, and paves the way for similar studies of other exotic hadron candidates. 
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    Free, publicly-accessible full text available December 1, 2026
  7. A first search for beyond the standard model physics in jet multiplicity patterns of multilepton events is presented, using a data sample corresponding to an integrated luminosity of 138 fb 1 of 13 TeV proton-proton collisions recorded by the CMS detector at the LHC. The search uses observed jet multiplicity distributions in one-, two-, and four-lepton events to explore possible enhancements in jet production rate in three-lepton events with and without bottom quarks. The data are found to be consistent with the standard model expectation. The results are interpreted in terms of supersymmetric production of electroweak chargino-neutralino superpartners with cascade decays terminating in prompt hadronic R -parity violating interactions. 
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    Free, publicly-accessible full text available December 1, 2026
  8. A search for the rare decay D 0 μ + μ is reported using proton-proton collision events at s = 13.6 TeV collected by the CMS detector in 2022–2023, corresponding to an integrated luminosity of 64.5 fb 1 . This is the first analysis to use a newly developed inclusive dimuon trigger, expanding the scope of the CMS flavor physics program. The search uses D 0 mesons obtained from D * + D 0 π + decays. No significant excess is observed. A limit on the branching fraction of B ( D 0 μ + μ ) < 2.4 × 10 9 at 95% confidence level is set. This is the most stringent upper limit set on any flavor changing neutral current decay in the charm sector. 
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    Free, publicly-accessible full text available October 1, 2026
  9. A<sc>bstract</sc> A search for a heavy pseudoscalar Higgs boson, A, decaying to a 125 GeV Higgs boson h and a Z boson is presented. The h boson is identified via its decay to a pair of tau leptons, while the Z boson is identified via its decay to a pair of electrons or muons. The search targets the production of the A boson via the gluon-gluon fusion process, gg → A, and in association with bottom quarks,$$\text{b}\overline{\text{b}}\text{A }$$. The analysis uses a data sample corresponding to an integrated luminosity of 138 fb−1collected with the CMS detector at the CERN LHC in proton-proton collisions at a centre-of-mass energy of$$\sqrt{s}=13$$TeV. Constraints are set on the product of the cross sections of the A production mechanisms and the A → Zh decay branching fraction. The observed (expected) upper limit at 95% confidence level ranges from 0.049 (0.060) pb to 1.02 (0.79) pb for the gg → A process and from 0.053 (0.059) pb to 0.79 (0.61) pb for the$$\text{b}\overline{\text{b}}\text{A }$$process in the probed range of the A boson mass,mA, from 225 GeV to 1 TeV. The results of the search are used to constrain parameters within the$${\text{M}}_{\text{h},\text{EFT}}^{125}$$benchmark scenario of the minimal supersymmetric extension of the standard model. Values of tanβbelow 2.2 are excluded in this scenario at 95% confidence level for allmAvalues in the range from 225 to 350 GeV. 
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    Free, publicly-accessible full text available October 1, 2026