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We perform numerical analysis of double-pinched Borel-Laplace QCD sum rules for the strangeless semihadronic $\tau$-decay data of ALEPH Collaboration in the (V+A)-channel. The $D=0$ contribution to the theoretical contour integral in the sum rules is evaluated by two related (truncated) Fixed Order perturbation theory methods (FO and ${\widetilde {\rm FO}}$), and by Principal Value (PV) of the Borel integration. We use for the full Adler function the Operator Product Expansion (OPE) with the terms of dimension $D=0, 4, 6$. The $D=6$ OPE contribution in this work, with two terms, is improved in comparison with our previous works [1, 2], in the sense that it involves the recently known noninteger values $\gamma^{(1)}(O_6^{(j)})/\beta_0$ of the effective leading-order anomalous dimensions. The higher order terms of the $D=0$ part of the Adler function are generated in a renormalon-motivated approach, in such a way that the resulting renormalon ambiguities originating from the infrared renormalons at $u=2, 3$ can be cancelled by the corresponding $D=4, 6$ OPE contributions of the Adler function. The Borel-Laplace sum rules are then used to extract, at each truncation index $N_t$ in the considered methods (FO, ${\widetilde {\rm FO}}$, PV), the values of the coupling $\alpha_s$ and of the condensates $\langle O_4 \rangle$, $\langle O_6^{(1)} \rangle$ and $\langle O_6^{(2)} \rangle$. The optimal values of the index $N_t$, in each method, is then determined by requiring the local insensitivity of the resulting double-pinched momenta $a^{(2,0)}$ and $a^{(2,1)}$. Averaging over the three methods, the extracted value of the ${\bar {\rm MS}}$ coupling is $\alpha_s(m_{\tau}^2) = 0.3179^{+0.0051}_{-0.0087}$, corresponding to $\alpha_s(M_Z^2)=0.1184^{+0.0007}_{-0.0011}$., Comment: 25 pages, 8 figures

We obtain an improved determination of the normalization of the leading infrared renormalon of the Bjorken sum rule: $Z_B (n_f=3)= -0.407\pm 0.119 $. Estimates of higher order terms of the perturbative series are given. We compute the Bjorken sum rule with hyperasymptotic precision by including the leading terminant, associated with the first infrared renormalon. We fit the experimental data to the operator product expansion theoretical prediction with $\hat f_{3}^{\rm PV}$ as the free parameter. We obtain a good agreement with the experiment with $\hat f_{3}^{\rm PV}\times 10^3=32^{+187}_{-196}\;{\rm GeV}^{2}$ for $Q^2 \geq 1$ GeV$^2$., Comment: 25 pages, 8 Figures; v2: small numerical modification due to finite charm mass corrections. Physical results unchanged. References added. It matches the PRD version

We use improved truncated Operator Product Expansion (OPE) for the Adler function, involving two types of terms with dimension $D=6$, in the double-pinched Borel-Laplace Sum Rules and Finite Energy Sum Rules for the V+A channel strangeless semihadronic $\tau$ decays. The generation of the higher order perturbative QCD terms of the $D=0$ part of the Adler function is carried out using a renormalon-motivated ansatz incorporating the leading UV renormalon and the first two leading IR renormalons. The trunacted $D=0$ part of the Sum Rules is evaluated by two variants of the fixed-order perturbation theory (FO), by Principal Value of the Borel resummation (PV), and by contour-improved perturbation theory (CI). For the experimental V+A channel spectral function we use the ALEPH $\tau$-decay data. We point out that the truncated FO and PV evaluation methods account correctly for the renormalon structure of the Sum Rules, while this is not the case for the truncated CI evaluation. We extract the value of the ${\overline {\rm MS}}$ coupling $\alpha_s(m_{\tau}^2) = 0.3235^{+0.0138}_{-0.0126}$ [$\alpha_s(M_Z^2)=0.1191 \pm 0.0016$] for the average of the two FO methods and the PV method, which we consider as our main result. If we included in the average also CI extraction, the value would be $\alpha_s(m_{\tau}^2) = 0.3299^{+0.0232}_{-0.0225}$ [$\alpha_s(M_Z^2)=0.1199^{+0.0026}_{-0.0028}$]. This work is an extension and improvement of our previous work [Eur.Phys.J.C81 (2021) 10, 930] where we used for the truncated OPE a more naive (and widely used) form and where the extracted values for $\alpha_s(M_Z^2)$ were somewhat lower., Comment: v3: 20 pages, 6 figures; corrected list of references

We present a determination of the perturbative QCD (pQCD) coupling using the V+A channel ALEPH $\tau$-decay data. The determination involves the double-pinched Borel-Laplace Sum Rules and Finite Energy Sum Rules. The theoretical basis is the Operator Product Expansion (OPE) of the V+A channel Adler function in which the higher order terms of the leading-twist part originate from a model based on the known structure of the leading renormalons of this quantity. The applied evaluation methods are contour-improved perturbation theory (CIPT), fixed-order perturbation theory (FOPT), and Principal Value of the Borel resummation (PV). All the methods involve truncations in the order of the coupling. In contrast to the truncated CIPT method, the truncated FOPT and PV methods account correctly for the suppression of various renormalon contributions of the Adler function in the mentioned sum rules. The extracted value of the ${\overline {\rm MS}}$ coupling is $\alpha_s(m_{\tau}^2) = 0.3116 \pm 0.0073$ [$\alpha_s(M_Z^2)=0.1176 \pm 0.0010$] for the average of the FOPT and PV methods, which we regard as our main result. On the other hand, if we include in the average also the CIPT method, the resulting values are significantly higher, $\alpha_s(m_{\tau}^2) = 0.3194 \pm 0.0167$ [$\alpha_s(M_Z^2)=0.1186 \pm 0.0021$]., Comment: v3: 36 pages, 11 figures. Matched published version

We give the hyperasymptotic expansion of the energy of a static quark-antiquark pair with a precision that includes the effects of the subleading renormalon. The terminants associated to the first and second renormalon are incorporated in the analysis when necessary. In particular, we determine the normalization of the leading renormalon of the force and, consequently, of the subleading renormalon of the static potential. We obtain $Z_3^F(n_f=3)=2Z_3^V(n_f=3)=0.37(17)$. The precision we reach in strict perturbation theory is next-to-next-to-next-to-leading logarithmic resummed order both for the static potential and for the force. We find that the resummation of large logarithms and the inclusion of the leading terminants associated to the renormalons are compulsory to get accurate determinations of $\Lambda_{\overline{\rm MS}}$ when fitting to short-distance lattice data of the static energy. We obtain $\Lambda_{\overline{\rm MS}}^{(n_f=3)}=338(12)$ MeV and $\alpha(M_z)=0.1181(9)$. We have also found strong consistency checks that the ultrasoft correction to the static energy can be computed at weak coupling in the energy range we have studied., Comment: 37 pages, 14 figures. References added. Minor modification. To meet journal version

We give the hyperasymptotic expansion of the plaquette with a precision that includes the terminant associated to the leading renormalon. Subleading effects are also considered. The perturbative series is regulated using the principal value prescription for its Borel integral. We use this analysis to give a determination of the gluon condensate in SU(3) pure gluodynamics that is independent of the scale and renormalization scheme used for the coupling constant: $\langle G^2 \rangle_{\rm PV} (n_f=0)=3.15(18)\; r_0^{-4}$., Comment: 20 pages, 9 figure. To meet journal version

We give the hyperasymptotic expansion of the plaquette with a precision that includes the terminant associated to the leading renormalon. Subleading effects are also considered. The perturbative series is regulated using the principal value prescription for its Borel integral. We use this analysis to give a determination of the gluon condensate in SU(3) pure gluodynamics that is independent of the scale and renormalization scheme used for the coupling constant: $\langle G^2 \rangle_{\rm PV} (n_f=0)=3.15(18)\; r_0^{-4}$., Comment: 20 pages, 9 figure. To meet journal version

We give the hyperasymptotic expansion of the energy of a static quark-antiquark pair with a precision that includes the effects of the subleading renormalon. The terminants associated to the first and second renormalon are incorporated in the analysis when necessary. In particular, we determine the normalization of the leading renormalon of the force and, consequently, of the subleading renormalon of the static potential. We obtain $Z_3^F(n_f=3)=2Z_3^V(n_f=3)=0.37(17)$. The precision we reach in strict perturbation theory is next-to-next-to-next-to-leading logarithmic resummed order both for the static potential and for the force. We find that the resummation of large logarithms and the inclusion of the leading terminants associated to the renormalons are compulsory to get accurate determinations of $\Lambda_{\overline{\rm MS}}$ when fitting to short-distance lattice data of the static energy. We obtain $\Lambda_{\overline{\rm MS}}^{(n_f=3)}=338(12)$ MeV and $\alpha(M_z)=0.1181(9)$. We have also found strong consistency checks that the ultrasoft correction to the static energy can be computed at weak coupling in the energy range we have studied., Comment: 37 pages, 14 figures. References added. Minor modification. To meet journal version

We evaluate QCD effects in the neutrinoless double beta ($0\nu\beta\beta$) decay, originating from new physics short-range mechanism in the form of five dimension-9 operators. For this, we employ the one-loop and two-loop renormalization group equations (RGEs) for the corresponding Wilson coefficients, performing the RGE-evolution from the new physics scales (estimated as $\Lambda ~ \sim 10^2$ GeV) to the typical spacelike $0\nu\beta\beta$-scale $Q \sim 0.1$ GeV. Since the latter scale is clearly nonperturbative, we apply various infrared-safe (IR-safe) variants of QCD where the running coupling has no Landau singularities at low spacelike $Q$. We point out that the correct treatment of the IR-safe analogs of the (noninteger) powers of the couplings is important. It turns out that in most cases of the considered operators the resulting QCD effects can be significant in this process, i.e., can be stronger than the effects of the present uncertainties in the nuclear matrix elements., Comment: 34 pages, 11 figures. v3: discussions added, principally in the new Sec. VI; results unchanged; version published in Phys. Rev. D; App.B is based partly on App.B of arXiv:1812.01580

We give the hyperasymptotic expansion of the plaquette with a precision that includes the terminant associated to the leading renormalon. Subleading effects are also considered. The perturbative series is regulated using the principal value prescription for its Borel integral. We use this analysis to give a determination of the gluon condensate in SU(3) pure gluodynamics that is independent of the scale and renormalization scheme used for the coupling constant: $\langle G^2 \rangle_{\rm PV} (n_f=0)=3.15(18)\; r_0^{-4}$., Comment: 20 pages, 9 figure. To meet journal version

We give the hyperasymptotic expansion of the energy of a static quark-antiquark pair with a precision that includes the effects of the subleading renormalon. The terminants associated to the first and second renormalon are incorporated in the analysis when necessary. In particular, we determine the normalization of the leading renormalon of the force and, consequently, of the subleading renormalon of the static potential. We obtain $Z_3^F(n_f=3)=2Z_3^V(n_f=3)=0.37(17)$. The precision we reach in strict perturbation theory is next-to-next-to-next-to-leading logarithmic resummed order both for the static potential and for the force. We find that the resummation of large logarithms and the inclusion of the leading terminants associated to the renormalons are compulsory to get accurate determinations of $\Lambda_{\overline{\rm MS}}$ when fitting to short-distance lattice data of the static energy. We obtain $\Lambda_{\overline{\rm MS}}^{(n_f=3)}=338(12)$ MeV and $\alpha(M_z)=0.1181(9)$. We have also found strong consistency checks that the ultrasoft correction to the static energy can be computed at weak coupling in the energy range we have studied., Comment: 37 pages, 14 figures. References added. Minor modification. To meet journal version

We give the hyperasymptotic expansion of the energy of a static quark-antiquark pair with a precision that includes the effects of the subleading renormalon. The terminants associated to the first and second renormalon are incorporated in the analysis when necessary. In particular, we determine the normalization of the leading renormalon of the force and, consequently, of the subleading renormalon of the static potential. We obtain $Z_3^F(n_f=3)=2Z_3^V(n_f=3)=0.37(17)$. The precision we reach in strict perturbation theory is next-to-next-to-next-to-leading logarithmic resummed order both for the static potential and for the force. We find that the resummation of large logarithms and the inclusion of the leading terminants associated to the renormalons are compulsory to get accurate determinations of $\Lambda_{\overline{\rm MS}}$ when fitting to short-distance lattice data of the static energy. We obtain $\Lambda_{\overline{\rm MS}}^{(n_f=3)}=338(12)$ MeV and $\alpha(M_z)=0.1181(9)$. We have also found strong consistency checks that the ultrasoft correction to the static energy can be computed at weak coupling in the energy range we have studied., Comment: 37 pages, 14 figures. References added. Minor modification. To meet journal version

We give the hyperasymptotic expansion of the plaquette with a precision that includes the terminant associated to the leading renormalon. Subleading effects are also considered. The perturbative series is regulated using the principal value prescription for its Borel integral. We use this analysis to give a determination of the gluon condensate in SU(3) pure gluodynamics that is independent of the scale and renormalization scheme used for the coupling constant: $\langle G^2 \rangle_{\rm PV} (n_f=0)=3.15(18)\; r_0^{-4}$., Comment: 20 pages, 9 figure. To meet journal version

Given an observable and its operator product expansion (OPE), we present expressions that carefully disentangle truncated sums of the perturbative series in powers of $\alpha$ from the non-perturbative (NP) corrections. This splitting is done with NP power accuracy. Analytic control of the splitting is achieved and the organization of the different terms is done along an super/hyper-asymptotic expansion. As a test we apply the methods to the static potential in the large $\beta_0$ approximation. We see the superasymptotic and hyperasymptotic structure of the observable in full glory., Comment: 60 pages, 11 figures, 2 Tables. Minor changes to meet journal version. Conclusions unchanged

My dissertation examines the unique case of South Korean tenant shopkeepers waging collective actions to protect themselves from dispossession and displacement while mobilizing under their collective identity as workers. Korea presents an optimal site for analyzing when and how the precarity caused by tenants’ lack of rights over their shops—a crucial means of production for tenant workers—can activate the formation of a new class consciousness. This case study pushes the existing labor literature to question the boundary of the working class. With the labor literature’s predominant focus on wage workers, self-employed workers are too often ignored as part of the modern proletariat. Yet, self-employed workers continue to constitute a large proportion of the global workforce in late industrialized and developing countries, and these workers tend to be low-skilled, low-educated, elderly and retired workers pushed out of the formal workforce. The precarity of the self-employed is especially salient in Asia and Africa where the fastest rates of urbanization are occurring, accompanied by intensifying speculation in urban spaces, which exacerbates the precarity of those who depend on urban space to make a living—i.e., independent waste pickers, street vendors, and artists, along with tenant shopkeepers. I argue that the lopsided representation of the working class can create major blind spots in our ability to identify agents of social change. To elucidate the processes that newly led these workers to organize, I combine theories of class formation, social transformation, and social movements from the political sociology literature with an analysis of space drawing from the urban scholarship. I find that tenant shopkeepers creatively utilize urban spaces that their shops occupy by transforming these mundane spaces of commerce into symbolic spaces of political resistance. Through such practices, urban space becomes not only a source of workers’ precarity but also a space f

These proceedings review recent work on hyperasymptotic constructions to the operator product expansion. Quantities we consider are the static potential and the pole mass., Comment: 9 pages, 7 figures, Proceedings for the 22th International Conference in Quantum Chromodynamics (QCD 19), 2-5 July 2019, Montpellier, France

We construct hyperasymptotic expansions for the heavy quark pole mass regulated using the principal value (PV) prescription. We apply such hyperasymptotic expansions to the $B/D$ meson masses, and $\bar \Lambda $ computed in the lattice. The issue of the uncertainty of the (top) pole mass is critically reexamined. The present theoretical uncertainty in the relation between ${\bar m}_t$, the $\bar{\rm MS}$ top mass, and $m_{t, \rm PV}$, the top pole mass regulated using the PV prescription, is numerically assessed to be $\delta m_{t,\rm PV}= 28\;{\rm MeV}$ for ${\bar m}_t =163$ GeV., Comment: 52 pages, 27 figures; v2: 56 pages, extra clarifications, one extra appendix, added references. Journal version

Given an observable and its operator product expansion (OPE), we present expressions that carefully disentangle truncated sums of the perturbative series in powers of $\alpha$ from the non-perturbative (NP) corrections. This splitting is done with NP power accuracy. Analytic control of the splitting is achieved and the organization of the different terms is done along an super/hyper-asymptotic expansion. As a test we apply the methods to the static potential in the large $\beta_0$ approximation. We see the superasymptotic and hyperasymptotic structure of the observable in full glory., Comment: 60 pages, 11 figures, 2 Tables. Minor changes to meet journal version. Conclusions unchanged

My dissertation examines the unique case of South Korean tenant shopkeepers waging collective actions to protect themselves from dispossession and displacement while mobilizing under their collective identity as workers. Korea presents an optimal site for analyzing when and how the precarity caused by tenants’ lack of rights over their shops—a crucial means of production for tenant workers—can activate the formation of a new class consciousness. This case study pushes the existing labor literature to question the boundary of the working class. With the labor literature’s predominant focus on wage workers, self-employed workers are too often ignored as part of the modern proletariat. Yet, self-employed workers continue to constitute a large proportion of the global workforce in late industrialized and developing countries, and these workers tend to be low-skilled, low-educated, elderly and retired workers pushed out of the formal workforce. The precarity of the self-employed is especially salient in Asia and Africa where the fastest rates of urbanization are occurring, accompanied by intensifying speculation in urban spaces, which exacerbates the precarity of those who depend on urban space to make a living—i.e., independent waste pickers, street vendors, and artists, along with tenant shopkeepers. I argue that the lopsided representation of the working class can create major blind spots in our ability to identify agents of social change. To elucidate the processes that newly led these workers to organize, I combine theories of class formation, social transformation, and social movements from the political sociology literature with an analysis of space drawing from the urban scholarship. I find that tenant shopkeepers creatively utilize urban spaces that their shops occupy by transforming these mundane spaces of commerce into symbolic spaces of political resistance. Through such practices, urban space becomes not only a source of workers’ precarity but also a space f

These proceedings review recent work on hyperasymptotic constructions to the operator product expansion. Quantities we consider are the static potential and the pole mass., Comment: 9 pages, 7 figures, Proceedings for the 22th International Conference in Quantum Chromodynamics (QCD 19), 2-5 July 2019, Montpellier, France

Given an observable and its operator product expansion (OPE), we present expressions that carefully disentangle truncated sums of the perturbative series in powers of $\alpha$ from the non-perturbative (NP) corrections. This splitting is done with NP power accuracy. Analytic control of the splitting is achieved and the organization of the different terms is done along an super/hyper-asymptotic expansion. As a test we apply the methods to the static potential in the large $\beta_0$ approximation. We see the superasymptotic and hyperasymptotic structure of the observable in full glory., Comment: 60 pages, 11 figures, 2 Tables. Minor changes to meet journal version. Conclusions unchanged

We construct hyperasymptotic expansions for the heavy quark pole mass regulated using the principal value (PV) prescription. We apply such hyperasymptotic expansions to the $B/D$ meson masses, and $\bar \Lambda $ computed in the lattice. The issue of the uncertainty of the (top) pole mass is critically reexamined. The present theoretical uncertainty in the relation between ${\bar m}_t$, the $\bar{\rm MS}$ top mass, and $m_{t, \rm PV}$, the top pole mass regulated using the PV prescription, is numerically assessed to be $\delta m_{t,\rm PV}= 28\;{\rm MeV}$ for ${\bar m}_t =163$ GeV., Comment: 52 pages, 27 figures; v2: 56 pages, extra clarifications, one extra appendix, added references. Journal version

Given an observable and its operator product expansion (OPE), we present expressions that carefully disentangle truncated sums of the perturbative series in powers of $\alpha$ from the non-perturbative (NP) corrections. This splitting is done with NP power accuracy. Analytic control of the splitting is achieved and the organization of the different terms is done along an super/hyper-asymptotic expansion. As a test we apply the methods to the static potential in the large $\beta_0$ approximation. We see the superasymptotic and hyperasymptotic structure of the observable in full glory., Comment: 60 pages, 11 figures, 2 Tables. Minor changes to meet journal version. Conclusions unchanged

We construct hyperasymptotic expansions for the heavy quark pole mass regulated using the principal value (PV) prescription. We apply such hyperasymptotic expansions to the $B/D$ meson masses, and $\bar \Lambda $ computed in the lattice. The issue of the uncertainty of the (top) pole mass is critically reexamined. The present theoretical uncertainty in the relation between ${\bar m}_t$, the $\bar{\rm MS}$ top mass, and $m_{t, \rm PV}$, the top pole mass regulated using the PV prescription, is numerically assessed to be $\delta m_{t,\rm PV}= 28\;{\rm MeV}$ for ${\bar m}_t =163$ GeV., Comment: 52 pages, 27 figures; v2: 56 pages, extra clarifications, one extra appendix, added references. Journal version

Experimental data obtained for the polarized Bjorken sum rule (BSR) $\Gamma_1^{p-n}(Q^2)$ are fitted by using predictions derived within a truncated operator product expansion (OPE) approach to QCD. Four QCD versions are considered: perturbative QCD (pQCD) in the MSbar scheme, Analytic Perturbation Theory (APT), and 2$\delta$ and 3$\delta$ analytic QCD versions. In contrast to pQCD, these QCD variants do not have Landau singularities at low positive $Q^2$, which facilitates the fitting procedure significantly. The fitting procedure is applied first to the experimental data of the inelastic part of BSR, and the known elastic contributions are added after the fitting. In general, when 2$\delta$ and 3$\delta$ QCD coupling is used the fitted curves give the best results, within the $Q^2$-range of the fit as well as in extended $Q^2$-intervals. When the fitting procedure is applied to the total BSR, i.e., to the sum of the experimental data and the elastic contribution, the quality of the results deteriorates significantly., Comment: 29 pages, 8 figures; to appear in EPJ C

El borrego cimarrón del desierto (Ovis canadensis) es una especie con una distribución espacial restringida, debido a que requiere de características específicas de hábitat que le provean agua, alimento, cobertura y espacio; factores determinantes en la selección de sitios de distribución. O. c. weemsi tiene el estatus de especie Sujeta a Protección Especial y, actualmente, solo se ha registrado en algunas zonas de Sonora, Baja California y Baja California Sur. La Isla El Carmen, Baja California Sur, pertenece al Parque Marino Nacional Bahía de Loreto, por su ubicación geográfica, condiciones climáticas, escasez de agua, tipos de vegetación y topoformas es un sitio de enorme interés para realizar investigaciones en ecosistemas de zonas áridas. Se determinó la distribución del borrego cimarrón (O c. weemsi) introducido en la Isla, mediante el método de conteo por franjas, modificado por Hayne; y el registro a través de avistamiento de ejemplares en los aguajes, para reforzar las observaciones de la estructura poblacional de la especie. Asimismo, se registraron la inclinación del terreno, época del año, distribución de aguajes y presencia de comederos para determinar su efecto en la estructura de la población. Se estimó una densidad de 4.96 borregos km-2, con un total de 1 151 observaciones. Se calcularon 616 individuos en una superficie de 12 428 ha con matorral desértico sarcocaule.

We consider a phenomenologycal parametrization of the QCD running coupling which arises from the dispersion relation respecting the holomorphic properties of the physical QCD observables in the complex momentum plane. The parameters are fixed by the following requirements: 1) at enough high energies, it reproduces the underlying perturbative coupling, 2) at intermediate energy momenta, it reproduces the experimental semihadronic tau decay ratio, and 3) in the deep IR regime, it satisfies the qualitative properties coming from recent lattice results. Finally, we apply this new coupling to low-energy available experimental data. In particular, to Borel sum rules for {\tau}-decay, extracting the values of the dimension 4 and 6 condensates, to the V-channel Adler function, and to polarized Bjorken Sum Rule., Comment: 6 pages, 1 table, 5 figures. Contribution to the proceedings of the 20th International Conference in Quantum Chromodynamics (QCD 17), 3 July - 7 July 2017, Montpellier, France

We investigate the Bjorken polarized sum rule (BSR) in three approaches to QCD with analytic (holomorphic) coupling: Analytic Perturbation Theory (APT), Two-delta analytic QCD (2$\delta$anQCD), and Three-delta lattice-motivated analytic QCD in the three-loop and four-loop MOM scheme (3l3$\delta$anQCD, 4l3$\delta$anQCD). These couplings do not have unphysical (Landau) singularities, and have finite values when the transferred momentum goes to zero, which allows us to explore the infrared regime. With the exception of APT, these theories at high momenta practically coincide with the underlying perturbative QCD (pQCD) in the same scheme. We apply them in order to verify the Bjorken sum rule within the range of energies available in the data collected by the experimental JLAB collaboration, i.e., $0.05 GeV^2

The product of the gluon dressing function and the square of the ghost dressing function in the Landau gauge can be regarded to represent, apart from the inverse power corrections 1/Q^{2n}, a nonperturbative generalization A(Q^2) of the perturbative QCD running coupling a(Q^2)=alpha_s(Q^2)/pi. Recent large volume lattice calculations for these dressing functions indicate that the coupling defined in such a way goes to zero as A(Q^2)~Q^2 when the squared momenta Q^2 go to zero (Q^2<<1 GeV^2). In this work we construct such a QCD coupling A(Q^2) which fulfills also various other physically motivated conditions. At high momenta it becomes the underlying perturbative coupling a(Q^2) to a very high precision. And at intermediate low squared momenta Q^2~1 GeV^2 it gives results consistent with the data of the semihadronic tau lepton decays as measured by OPAL and ALEPH. The coupling is constructed in a dispersive way, resulting as a byproduct in the holomorphic behavior of A(Q^2) in the complex Q^2-plane which reflects the holomorphic behavior of the spacelike QCD observables. Application of the Borel sum rules to tau-decay V+A spectral functions allows us to obtain values for the gluon (dimension-4) condensate and the dimension-6 condensate, which reproduce the measured OPAL and ALEPH data to a significantly better precision than the perturbative MSbar coupling approach., Comment: 43 pages, 15 figures, v4: improved presentation in the text, results unchanged; new references added ([7-8,28-29,40,44-45,47,52-53,127-128]); to appear in J.Phys.G

El borrego cimarrón del desierto (Ovis canadensis) es una especie con una distribución espacial restringida, debido a que requiere de características específicas de hábitat que le provean agua, alimento, cobertura y espacio; factores determinantes en la selección de sitios de distribución. O. c. weemsi tiene el estatus de especie Sujeta a Protección Especial y, actualmente, solo se ha registrado en algunas zonas de Sonora, Baja California y Baja California Sur. La Isla El Carmen, Baja California Sur, pertenece al Parque Marino Nacional Bahía de Loreto, por su ubicación geográfica, condiciones climáticas, escasez de agua, tipos de vegetación y topoformas es un sitio de enorme interés para realizar investigaciones en ecosistemas de zonas áridas. Se determinó la distribución del borrego cimarrón (O c. weemsi) introducido en la Isla, mediante el método de conteo por franjas, modificado por Hayne; y el registro a través de avistamiento de ejemplares en los aguajes, para reforzar las observaciones de la estructura poblacional de la especie. Asimismo, se registraron la inclinación del terreno, época del año, distribución de aguajes y presencia de comederos para determinar su efecto en la estructura de la población. Se estimó una densidad de 4.96 borregos km-2, con un total de 1 151 observaciones. Se calcularon 616 individuos en una superficie de 12 428 ha con matorral desértico sarcocaule.

El borrego cimarrón del desierto (Ovis canadensis) es una especie con una distribución espacial restringida, debido a que requiere de características específicas de hábitat que le provean agua, alimento, cobertura y espacio; factores determinantes en la selección de sitios de distribución. O. c. weemsi tiene el estatus de especie Sujeta a Protección Especial y, actualmente, solo se ha registrado en algunas zonas de Sonora, Baja California y Baja California Sur. La Isla El Carmen, Baja California Sur, pertenece al Parque Marino Nacional Bahía de Loreto, por su ubicación geográfica, condiciones climáticas, escasez de agua, tipos de vegetación y topoformas es un sitio de enorme interés para realizar investigaciones en ecosistemas de zonas áridas. Se determinó la distribución del borrego cimarrón (O c. weemsi) introducido en la Isla, mediante el método de conteo por franjas, modificado por Hayne; y el registro a través de avistamiento de ejemplares en los aguajes, para reforzar las observaciones de la estructura poblacional de la especie. Asimismo, se registraron la inclinación del terreno, época del año, distribución de aguajes y presencia de comederos para determinar su efecto en la estructura de la población. Se estimó una densidad de 4.96 borregos km-2, con un total de 1 151 observaciones. Se calcularon 616 individuos en una superficie de 12 428 ha con matorral desértico sarcocaule.

We compute the right top quark coupling in the aligned two-Higgs-doublet model. In the Standard Model the real part of this coupling is dominated by QCD-gluon-exchange diagram, but the imaginary part, instead, is purely electroweak at one loop. Within this model we show that values for the imaginary part of the coupling up to one order of magnitude larger than the electroweak prediction can be obtained. For the real part of the electroweak contribution we find that it can be up to three orders of magnitude larger than the standard model one. We also present detailed results of the one loop analytical computation.

Newer lattice results indicate that, in the Landau gauge at low spacelike momenta, the gluon propagator and the ghost dressing function are finite nonzero. This leads to a definition of the QCD running coupling, in a specific scheme, that goes to zero at low spacelike momenta. We construct a running coupling which fulfills these conditions, and at the same time reproduces to a high precision the perturbative behavior at high momenta. The coupling is constructed in such a way that it reflects qualitatively correctly the holomorphic (analytic) behavior of spacelike observables in the complex plane of the squared momenta, as dictated by the general principles of Quantum Field Theories. Further, we require the coupling to reproduce correctly the nonstrange semihadronic decay rate of tau lepton which is the best measured low-momentum QCD observable with small higher-twist effects. Subsequent application of the Borel sum rules to the V+A spectral functions of tau lepton decays, as measured by OPAL Collaboration, determines the values of the gluon condensate and of the V+A 6-dimensional condensate, and reproduces the data to a significantly higher precision than the usual MSbar running coupling., Comment: v4: 23 pages, 9 figures; improved discussion; new Sec.V and new references added; version to appear in J.Phys.G

We update our perturbative determination of MSbar bottom quark mass mb(mb), by including the recently obtained four-loop coefficient in the relation between the pole and MSbar mass. First the renormalon subtracted (RS or RS') mass is determined from the known mass of the Upsilon(1S) meson, where we use the renormalon residue Nm obtained from the asymptotic behavior of the coefficient of the 3-loop static singlet potential. MSbar mass is then obtained using the 4-loop renormalon-free relation between the RS (RS') and MSbar mass. We argue that the effects of the charm quark mass are accounted for by effectively using Nf=3 in the mass relations. The extracted value is mb(mb) = 4222(40) MeV, where the uncertainty is dominated by the renormalization scale dependence., Comment: 6 pages; presented at ACAT 2016, 18-22 January 2016, UTFSM, Valparaiso, Chile

We provide three Fortran programs which evaluate the QCD analytic (holomorphic) couplings $\mathcal{A}_{\nu}(Q^2)$ for complex or real squared momenta $Q^2$. These couplings are holomorphic analogs of the powers $a(Q^2)^{\nu}$ of the underlying perturbative QCD (pQCD) coupling $a(Q^2) \equiv \alpha_s(Q^2)/\pi$, in three analytic QCD models (anQCD): Fractional Analytic Perturbation Theory (FAPT), Two-delta analytic QCD (2$\delta$anQCD), and Massive Perturbation Theory (MPT). The index $\nu$ can be noninteger. The provided programs do basically the same job as the Mathematica package anQCD.m in Mathematica published by us previously, Ref.[1], but are now written in Fortran., Comment: 7 pages; the programs can be downloaded from the web page gcvetic.usm.cl

We apply (Fractional) Analytic Perturbation Theory (FAPT) to the QCD analysis of the nonsinglet nucleon structure function $F_2(x,Q^2)$ in deep inelastic scattering up to the next leading order and compare the results with ones obtained within the standard perturbation QCD. Based on a popular parameterization of the corresponding parton distribution we perform the analysis within the Jacobi Polynomial formalism and under the control of the numerical inverse Mellin transform. To reveal the main features of the FAPT two-loop approach, we consider a wide range of momentum transfer from high $Q^2\sim 100 {\rm GeV}^2$ to low $Q^2\sim 0.3 {\rm GeV}^2$ where the approach still works., Comment: 14 pages, 4 figures, 1 table; v3: Improve clarity and some details, references are also added. Version accepted for publication in PRD

We implement our past investigations in the quark-antiquark interaction through a non-perturbative running coupling defined in terms of a gluon mass function, similar to that used in some Schwinger-Dyson approaches. This coupling leads to a quark-antiquark potential, which satisfies not only asymptotic freedom but also describes linear confinement correctly. From this potential, we calculate the bottomonium and charmonium spectra below the first open flavor meson-meson thresholds and show that for a small range of values of the free parameter determining the gluon mass function an excellent agreement with data is attained., Comment: 13 pages, 4 figures; v3: version accepted for publication in Journal of Physics G

We provide three Fortran programs which evaluate the QCD analytic (holomorphic) couplings $\mathcal{A}_{\nu}(Q^2)$ for complex or real squared momenta $Q^2$. These couplings are holomorphic analogs of the powers $a(Q^2)^{\nu}$ of the underlying perturbative QCD (pQCD) coupling $a(Q^2) \equiv \alpha_s(Q^2)/\pi$, in three analytic QCD models (anQCD): Fractional Analytic Perturbation Theory (FAPT), Two-delta analytic QCD (2$\delta$anQCD), and Massive Perturbation Theory (MPT). The index $\nu$ can be noninteger. The provided programs do basically the same job as the Mathematica package anQCD.m in Mathematica published by us previously, Ref.[1], but are now written in Fortran., Comment: 7 pages; the programs can be downloaded from the web page gcvetic.usm.cl

We apply (Fractional) Analytic Perturbation Theory (FAPT) to the QCD analysis of the nonsinglet nucleon structure function $F_2(x,Q^2)$ in deep inelastic scattering up to the next leading order and compare the results with ones obtained within the standard perturbation QCD. Based on a popular parameterization of the corresponding parton distribution we perform the analysis within the Jacobi Polynomial formalism and under the control of the numerical inverse Mellin transform. To reveal the main features of the FAPT two-loop approach, we consider a wide range of momentum transfer from high $Q^2\sim 100 {\rm GeV}^2$ to low $Q^2\sim 0.3 {\rm GeV}^2$ where the approach still works., Comment: 14 pages, 4 figures, 1 table; v3: Improve clarity and some details, references are also added. Version accepted for publication in PRD

We outline here the motivation for the existence of analytic QCD models, i.e., QCD frameworks in which the running coupling $A(Q^2)$ has no Landau singularities. The analytic (holomorphic) coupling $A(Q^2)$ is the analog of the underlying pQCD coupling $a(Q^2) \equiv \alpha_s(Q^2)/\pi$, and any such $A(Q^2)$ defines an analytic QCD model. We present the general construction procedure for the couplings $A_{\nu}(Q^2)$ which are analytic analogs of the powers $a(Q^2)^{\nu}$. Three analytic QCD models are presented. Applications of our program (in Mathematica) for calculation of $A_{\nu}(Q^2)$ in such models are presented. Programs in both Mathematica and Fortran can be downloaded from the web page: gcvetic.usm.cl., Comment: 7 pages, 2 figures; uses JPConf style; based on the presentation given by G.C. at the 16th International workshop on Advanced Computing and Analysis Techniques in physics research (ACAT 2014), Prague, Czech Republic, September 1-5, 2014; to appear in the proceedings by the IOP Conference Series publishing

We provide a Mathematica package that evaluates the QCD analytic couplings (in the Euclidean domain) $\mathcal{A}_{\nu}(Q^2)$, which are analytic analogs of the powers $a(Q^2)^{\nu}$ of the underlying perturbative QCD (pQCD) coupling $a(Q^2) \equiv \alpha_s(Q^2)/\pi$, in three analytic QCD models (anQCD): Fractional Analytic Perturbation Theory (FAPT), Two-delta analytic QCD (2$\delta$anQCD), and Massive Perturbation Theory (MPT). The analytic (holomorphic) running couplings $\mathcal{A}_{\nu}(Q^2)$, in contrast to the corresponding pQCD expressions $a(Q^2)^{\nu}$, reflect correctly the analytic properties of the spacelike observables ${\cal D}(Q^2)$ in the complex $Q^2$ plane as dictated by the general principles of quantum field theory. They are thus more suited for evaluations of such physical quantities, especially at low momenta $|Q^2| \sim 1 \ {\rm GeV}^2$., Comment: v3: 35 pp., 7 figs.; improved programs which work in Mathematica 9 and 10; improved presentation of the text (Sec.2 shorter, Sec.4 enlarged); to appear in Computer Physics Communications

We obtain an improved determination of the normalization constant of the first infrared renormalon of the pole mass (and the singlet static potential). For $N_f=3$ it reads $N_m=0.563(26)$. Charm quark effects in the bottom quark mass determination are carefully investigated. Finally, we determine the bottom quark mass using the NNNLO perturbative expression for the $\Upsilon(1S)$ mass. We work in the renormalon subtracted scheme, which allows us to control the divergence of the perturbation series due to pole mass renormalon. Our result for the ${\overline {\rm MS}}$ mass reads ${\overline m}_{b}({\overline m}_{b})=4201(43)$ MeV., Comment: 37 pages, 11 figures, minor changes in presentation, version to appear in JHEP

We consider the gluon propagator in the Landau gauge at low spacelike momenta and with the dressing function $Z(Q^2)$ at the two-loop order. We incorporate the nonperturbative effects by making the (noninteger) powers of the QCD coupling in the dressing function $Z(Q^2)$ analytic (holomorphic) via the Fractional Analytic Perturbation Theory (FAPT) model, and simultaneously introducing the gluon dynamical mass in the propagator as motivated by the previous analyses of the Dyson-Schwinger equations. The obtained propagator has behavior compatible with the unquenched lattice data ($N_f=2+1$) at low spacelike momenta $0.4 \ {\rm GeV} < Q \lesssim 10$ GeV. We conclude that the removal of the unphysical Landau singularities of the powers of the coupling via the (F)APT prescription, in conjunction with the introduction of the dynamical mass $M \approx 0.62$ GeV of the gluon, leads to an acceptable behavior of the propagator in the infrared regime., Comment: 9 pages, 3 figures

We provide a Mathematica package that evaluates the QCD analytic couplings (in the Euclidean domain) $\mathcal{A}_{\nu}(Q^2)$, which are analytic analogs of the powers $a(Q^2)^{\nu}$ of the underlying perturbative QCD (pQCD) coupling $a(Q^2) \equiv \alpha_s(Q^2)/\pi$, in three analytic QCD models (anQCD): Fractional Analytic Perturbation Theory (FAPT), Two-delta analytic QCD (2$\delta$anQCD), and Massive Perturbation Theory (MPT). The analytic (holomorphic) running couplings $\mathcal{A}_{\nu}(Q^2)$, in contrast to the corresponding pQCD expressions $a(Q^2)^{\nu}$, reflect correctly the analytic properties of the spacelike observables ${\cal D}(Q^2)$ in the complex $Q^2$ plane as dictated by the general principles of quantum field theory. They are thus more suited for evaluations of such physical quantities, especially at low momenta $|Q^2| \sim 1 \ {\rm GeV}^2$., Comment: v3: 35 pp., 7 figs.; improved programs which work in Mathematica 9 and 10; improved presentation of the text (Sec.2 shorter, Sec.4 enlarged); to appear in Computer Physics Communications

We outline here the motivation for the existence of analytic QCD models, i.e., QCD frameworks in which the running coupling $A(Q^2)$ has no Landau singularities. The analytic (holomorphic) coupling $A(Q^2)$ is the analog of the underlying pQCD coupling $a(Q^2) \equiv \alpha_s(Q^2)/\pi$, and any such $A(Q^2)$ defines an analytic QCD model. We present the general construction procedure for the couplings $A_{\nu}(Q^2)$ which are analytic analogs of the powers $a(Q^2)^{\nu}$. Three analytic QCD models are presented. Applications of our program (in Mathematica) for calculation of $A_{\nu}(Q^2)$ in such models are presented. Programs in both Mathematica and Fortran can be downloaded from the web page: gcvetic.usm.cl., Comment: 7 pages, 2 figures; uses JPConf style; based on the presentation given by G.C. at the 16th International workshop on Advanced Computing and Analysis Techniques in physics research (ACAT 2014), Prague, Czech Republic, September 1-5, 2014; to appear in the proceedings by the IOP Conference Series publishing

We obtain an improved determination of the normalization constant of the first infrared renormalon of the pole mass (and the singlet static potential). For $N_f=3$ it reads $N_m=0.563(26)$. Charm quark effects in the bottom quark mass determination are carefully investigated. Finally, we determine the bottom quark mass using the NNNLO perturbative expression for the $\Upsilon(1S)$ mass. We work in the renormalon subtracted scheme, which allows us to control the divergence of the perturbation series due to pole mass renormalon. Our result for the ${\overline {\rm MS}}$ mass reads ${\overline m}_{b}({\overline m}_{b})=4201(43)$ MeV., Comment: 37 pages, 11 figures, minor changes in presentation, version to appear in JHEP

We consider the gluon propagator in the Landau gauge at low spacelike momenta and with the dressing function $Z(Q^2)$ at the two-loop order. We incorporate the nonperturbative effects by making the (noninteger) powers of the QCD coupling in the dressing function $Z(Q^2)$ analytic (holomorphic) via the Fractional Analytic Perturbation Theory (FAPT) model, and simultaneously introducing the gluon dynamical mass in the propagator as motivated by the previous analyses of the Dyson-Schwinger equations. The obtained propagator has behavior compatible with the unquenched lattice data ($N_f=2+1$) at low spacelike momenta $0.4 \ {\rm GeV} < Q \lesssim 10$ GeV. We conclude that the removal of the unphysical Landau singularities of the powers of the coupling via the (F)APT prescription, in conjunction with the introduction of the dynamical mass $M \approx 0.62$ GeV of the gluon, leads to an acceptable behavior of the propagator in the infrared regime., Comment: 9 pages, 3 figures