Tue·Nov 1, 2016Tuesday·November 1, 2016

1. 01*

   FormTracer - A Mathematica Tracing Package Using FORM

   Anton K. Cyrol🇩🇪 · Mario Mitter🇩🇪 · Nils Strodthoff🇺🇸

   We present FormTracer, a high-performance, general purpose, easy-to-use Mathematica tracing package which uses FORM. It supports arbitrary space and spinor dimensions as well as an arbitrary number of simple compact Lie groups. While keeping the usability of the Mathematica interface, it relies on the efficiency of FORM. An additional performance gain is achieved by a decomposition algorithm that avoids redundant traces in the product tensors spaces. FormTracer supports a wide range of syntaxes which endows it with a high flexibility. Mathematica notebooks that automatically install the package and guide the user through performing standard traces in space-time, spinor and gauge-group spaces are provided.

   hep-phhep-thComput.Phys.Commun.(2017)·100 citations
2. 02*

   Testing Lorentz and CPT Symmetries in Penning Traps

   Yunhua Ding🇺🇸

   A modified Dirac equation with general Lorentz- and CPT-violating operators in the electromagnetic field is studied. Constraints on and possible sensitivities to Lorentz-violating coefficients in the nonminimal sector up to mass-dimension six can be obtained by analyzing Penning-trap results involving anomaly frequencies.

   hep-ph0 citations
3. 03*

   Inflection-point Higgs Inflation

   Nobuchika Okada🇺🇸 · Digesh Raut🇺🇸

   Inflection-point inflation is an interesting possibility to realize a successful slow-roll inflation when inflation is driven by a single scalar field with its initial value below the Planck mass (${\varphi }_I\lesssim M_{Pl}$). In order for a renormalization group (RG) improved effective $\lambda {\varphi }^4$ potential to develop an inflection-point, the quartic coupling $\lambda (\varphi )$ must exhibit a minimum with an almost vanishing value in its RG evolution, namely $\lambda ({\varphi }_I)\simeq 0$ and ${\beta }_{\lambda }({\varphi }_I)\simeq 0$, where ${\beta }_{\lambda }$ is the beta-function of the quartic coupling. As an example, we consider the minimal gauged $B-L$ extended Standard Model at the TeV scale, where we identify the $B-L$ Higgs field as the inflaton field. For a successful inflection-point inflation, which is consistent with the current cosmological observations, the mass ratios among the $Z^{\prime }$ gauge boson, the right-handed neutrinos and the $B-L$ Higgs boson are fixed. Our scenario can be tested in the future collider experiments such as the High-Luminosity LHC and the SHiP experiments. In addition, the inflection-point inflation provides a unique prediction for the running of the spectral index $\alpha \simeq -2.7\times 10^{-3}{\left(\frac{60}{N}\right)}^2$ ($N$ is the $e$-folding number), which can be tested in the near future.

   hep-phastro-ph.COPRD(2017)·42 citations
4. 04*

   Precision determination of the small-$x$ gluon from charm production at LHCb

   Rhorry Gauld🇬🇧 · Juan Rojo🇳🇱

   The small-$x$ gluon in global fits of parton distributions is affected by large uncertainties from the lack of direct experimental constraints. In this work we provide a precision determination of the small-$x$ gluon from the exploitation of forward charm production data provided by LHCb for three different centre-of-mass (CoM) energies: 5~TeV, 7~TeV and 13~TeV. The LHCb measurements are included in the PDF fit by means of normalized distributions and cross-section ratios between data taken at different CoM values, $R_{13/7}$ and $R_{13/5}$. We demonstrate that forward charm production leads to a reduction of the PDF uncertainties of the gluon down to $x\simeq 10^{-6}$ by up to an order of magnitude, with implications for high-energy colliders, cosmic ray physics and neutrino astronomy.

   hep-phhep-exPRL(2017)·106 citations
5. 05*

   The unexplored landscape of two-body resonances

   Nathaniel Craig🇺🇸 · Patrick Draper🇺🇸 · Kyoungchul Kong🇺🇸 · Yvonne Ng🇺🇸 · Daniel Whiteson🇺🇸

   We propose a strategy for searching for theoretically-unanticipated new physics which avoids a large trials factor by focusing on experimental strengths. Searches for resonances decaying into pairs of visible particles are experimentally very powerful due to the localized mass peaks and have a rich history of discovery. Yet, due to a focus on subsets of theoretically-motivated models, the landscape of such resonances is far from thoroughly explored. We survey the existing set of searches, identify untapped experimental opportunities and discuss the theoretical constraints on models which would generate such resonances.

   hep-phhep-exActa Phys.Polon.B(2019)·35 citations
6. 06*

   Neutralino pair production via photon-photon collisions at the ILC

   M. Demirci🇹🇷 · A. I. Ahmadov🇦🇿

   We provide complete one-loop predictions for the direct production of the neutralino pairs via photon-photon collisions which appears for the first time at one-loop level in the minimal supersymmetric standard model at the International Linear Collider. We present a comprehensive investigation of the dependence of total cross section on the center-of-mass energy and the tan$\beta$ for three different scenarios based on gaugino/Higgsino fractions of the neutralinos. Furthermore, by investigating the behavior with the most relevant parameters $\mu$ and $M_2$, we exhibit regions of the parameter space where the enhancement of the cross section is large enough to be detectable at linear colliders. Our analysis shows that the corresponding production cross section reaches its highest values when the lightest neutralino ${\tilde{\chi }}_1^0$ has a dominant Higgsino component and/or the next-to-lightest neutralino ${\tilde{\chi }}_2^0$ has a dominant gaugino component.

   hep-phPRD(2016)·10 citations
7. 07*

   Lorentz-Violating QCD Corrections to Deep Inelastic Scattering

   A. R. Vieira🇺🇸

   In this work, we present CPT- and Lorentz-violating corrections to observable quantities in electron-proton scattering. We also show how the theoretical prediction can be used together with data to establish bounds on a coefficient for CPT and Lorentz violation in the QCD sector.

   hep-phCPT and Lorentz Symmetry, pp. 232-234 (20…·0 citations
8. 08*

   $f_2(1810)$ as a triangle singularity

   Ju-Jun Xie🇨🇳 · Li-Sheng Geng🇨🇳 · Eulogio Oset🇪🇸

   We perform calculations showing that a source producing $K^{\ast }{\bar{K}}^{\ast }$ in $J=2$ and $L=0$ gives rise to a triangle singularity at $1810$ MeV with a width of about $200$ MeV from the mechanism $K^{\ast }\to \pi K$ and then $K{\bar{K}}^{\ast }$ merging into the $a_1(1260)$ resonance. We suggest that this is the origin of the present $f_2(1810)$ resonance and propose to look at the $\pi a_1(1260)$ mode in several reactions to clarify the issue.

   hep-phPRD(2017)·31 citations
9. 09*

   Puzzle of the ${\Lambda }_c$ spectrum

   Qi-Fang Lü🇨🇳 · Yubing Dong🇨🇳 · Xiang Liu🇨🇳 · Takayuki Matsuki🇯🇵

   There is a puzzle in the ${\Lambda }_c^{+}$ family, i.e., one member with $J^P=3/2^{+}$ is missing in a $L=2$ multiplet which the heavy quark effective theory predicts, and $J^P$'s of ${\Lambda }_c(2765{)}^{+}$ and ${\Lambda }_c(2940{)}^{+}$ are unknown. Using a light diquark picture to calculate baryon masses, we study possible assignments of two ${\Lambda }_c$'s with unknown $J^P$ and the missing ${\Lambda }_c^{+}$ with $3/2^{+}$ for $L=2$, and we find the most probable possibility that the peak corresponding to ${\Lambda }_c(2880{)}^{+}$ actually includes a missing member with spin $3/2^{+}$ for $L=2$ and that quantum numbers of ${\Lambda }_c(2765{)}^{+}$ and ${\Lambda }_c(2940{)}^{+}$ are $2S(1/2^{+})$ and $2P(1/2^{-})$, respectively.

   hep-phhep-exnucl-thNucl.Phys.Rev.(2018)·28 citations
10. 10*

    Field reparametrization in effective field theories

    Giampiero Passarino (Turin U. & INFN, Turin)🇮🇹

    Debate topic for Effective Field Theory (EFT) is the choice of a "basis" for $\text{mrdim}=6$ operators Clearly all bases are equivalent as long as they are a "basis", containing a minimal set of operators after the use of equations of motion and respecting gauge invariance. From a more formal point of view a basis is characterized by its closure with respect to renormalization. Equivalence of bases should always be understood as a statement for the S-matrix and not for the Lagrangian, as dictated by the equivalence theorem. Any phenomenological approach that misses one of these ingredients is still acceptable for a preliminar analysis, as long as it does not pretend to be an EFT. Here we revisit the equivalence theorem and its consequences for EFT when two sets of higher dimensional operators are connected by a set of non-linear, noninvariant, field reparametrizations.

    hep-phEur.Phys.J.Plus(2017)·38 citations
11. 11*

    Legendre Analysis of Hadronic Reactions

    Ya.I. Azimov🇷🇺

    Expansions over Legendre functions are suggested as a model-independent way of compact presentation of modern precise and high-statistics data for two-hadron reactions. Some properties of the expansions are described.

    hep-phhep-exnucl-exnucl-th1 citation
12. 12*

    Chiral phase transition of QCD with $N_f=2+1$ flavors from holography

    Danning Li🇨🇳 · Mei Huang🇨🇳

    Chiral phase transition for three-flavor $N_f=2+1$ QCD with $m_u=m_d\ne m_s$ is investigated in a modified soft-wall holographic QCD model. Solving temperature dependent chiral condensates from equations of motion of the modified soft-wall model, we extract the quark mass dependence of the order of chiral phase transition in the case of $N_f=2+1$, and the result is in agreement with the "Colombia Plot", which is summarized from lattice simulations and other non-perturbative methods. First order phase transition is observed around the three flavor chiral limit $m_{u/d}=0,m_s=0$, while at sufficient large quark masses it turns to be a crossover phase transition. The first order and crossover regions are separated by a second order phase transition line. The second order line is divided into two parts by the $m_{u/d}=m_s$ line, and the $m_s$ dependence of the transition temperature in these two parts are totally contrast, which might indicate that the two parts are governed by different universality classes.

    hep-phJHEP(2017)·47 citations
13. 13*

    Thermodynamical String Fragmentation

    Nadine Fischer🇦🇺 · Torbjörn Sjöstrand🇸🇪

    The observation of heavy-ion-like behaviour in pp collisions at the LHC suggests that more physics mechanisms are at play than traditionally assumed. The introduction e.g. of quark-gluon plasma or colour rope formation can describe several of the observations, but as of yet there is no established paradigm. In this article we study a few possible modifications to the Pythia event generator, which describes a wealth of data but fails for a number of recent observations. Firstly, we present a new model for generating the transverse momentum of hadrons during the string fragmentation process, inspired by thermodynamics, where heavier hadrons naturally are suppressed in rate but obtain a higher average transverse momentum. Secondly, close-packing of strings is taken into account by making the temperature or string tension environment-dependent. Thirdly, a simple model for hadron rescattering is added. The effect of these modifications is studied, individually and taken together, and compared with data mainly from the LHC. While some improvements can be noted, it turns out to be nontrivial to obtain effects as big as required, and further work is called for.

    hep-phJHEP(2017)·101 citations
14. 14*

    Neutrinos: Fast & Curious

    Gabriela Barenboim🇪🇸

    The Standard Model has been effective way beyond expectations in foreseeing the result of almost all the experimental tests done up so far. In it, neutrinos are massless. Nonetheless, in recent years we have collected solid proofs indicating little but non zero masses for the neutrinos (when contrasted with those of the charged leptons). These masses permit neutrinos to change their flavor and oscillate, indeed a unique treat. In these lectures, I discuss the properties and the amazing potential of neutrinos in and beyond the Standard Model.

    hep-ph2 citations
15. 15*

    Higgs Mass and Muon $g-2$ Anomaly in MSSM with Gauge-Gravity hybrid Mediation

    Bin Zhu🇨🇳 · Ran Ding🇨🇳 · Tianjun Li🇨🇳

    In general, we can propose the hybrid supersymmetry breakings and hybrid mediations in the Supersymmetric Standard Models (SSMs). In this paper, we study the hybrid mediation for supersymmetry (SUSY) breaking. In particular, we study how to keep the good properties of gravity mediation, gauge mediation, and anomaly mediation, while solve their problems simultaneously. As an example, we consider the anomaly-gravity mediation, where all the supersymmetric particles (sparticles) obtain the SUSY breaking soft terms from the traditional gravity mediation while gauge mediation gives dominant contributions to the soft terms in the colored sector due to the splitted messengers. Thus, we can realize the electroweak supersymmetry naturally where the sleptons, sneutrinos, and electroweakinos are light within one TeV while the squarks and gluino are heavy around a few TeVs. And then we can explain 125 GeV Higgs mass, satisfy the LHC SUSY search bounds, and explain the anomalous magnetic momement of muon, etc. Moreover, the gluino and squarks are well beyond the current LHC Run II searches.

    hep-phPRD(2017)·18 citations
16. 16*

    Delayed versus accelerated quarkonium formation in a magnetic field

    Kei Suzuki🇰🇷 · Su Houng Lee🇰🇷

    Formation time of heavy quarkonia in a homogeneous magnetic field is analyzed by using a phenomenological ansatz of the vector current correlator. Because the existence of a magnetic field mixes vector quarkonia ($J/\psi$, ${\psi }^{\prime }$) and their pseudoscalar partners (${\eta }_c$, ${\eta }_c^{\prime }$), the properties of the quarkonia can be modified through such a spin mixing. This means that the formation time of quarkonia is also changed by the magnetic field. We show the formation time of vector quarkonia is delayed by an idealized constant magnetic field, where the formation time of the excited state becomes longer than that of the ground state. As a more realistic situation in heavy-ion collisions, effects by a time-dependent magnetic field are also discussed, where delayed formation of $J/\psi$ and ${\psi }^{\prime }$ and very early formation of ${\eta }_c$ and ${\eta }_c^{\prime }$ are found.

    hep-phnucl-exnucl-thPRC(2017)·31 citations
17. 17*

    Effects of non-minimal Universal Extra Dimension on $B\to X_s\gamma$

    Anindya Datta (University of Calcutta)🇮🇳 · Avirup Shaw (Indian Association for the Cultivation of Science)🇮🇳

    We estimate contributions from Kaluza-Klein excitations of third generation quarks and gauge bosons to the branching ratio of $B\to X_s\gamma$ decay process in 5-Dimensional Universal Extra Dimensional scenario with non-vanishing boundary localised terms. This model is conventionally known as non-minimal Universal Extra Dimensional model. We have derived the lower limit on the size of the extra dimension by comparing our theoretical estimation of the branching ratio which includes next-to-next-to leading order QCD corrections with its experimentally measured value. Coefficients of the boundary localised terms have also been constrained. 95 \% C.L. lower limit on inverse of radius of compactification ($R^{-1}$) can be as large as 670 GeV for some choice of the value of coefficients of boundary localised terms.

    hep-phPRD(2017)·17 citations
18. 18*

    Fractal aspects of hadrons

    Airton Deppman🇧🇷 · Eugenio Megias🇪🇸

    The non extensive aspects of $p_T$ distributions obtained in high energy collisions are discussed in relation to possible fractal structure in hadrons, in the sense of the thermofractal structure recently introduced. The evidences of self-similarity in both theoretical and experimental works in High Energy and in Hadron Physics are discussed, to show that the idea of fractal structure of hadrons and fireballs have being under discussion for decades. The non extensive self-consistent thermodynamics and the thermofractal structure allow one to connect non extensivity to intermittence and possibly to parton distribution functions in a single theoretical framework.

    hep-phEPJ Web Conf.(2017)·7 citations
19. 19*

    Differential cross section for the Higgs boson production in 4-lepton channel and $k_T$-factorization

    Vaibhav S. Rawoot🇮🇳 · Rashidul Islam🇮🇳 · Mukesh Kumar🇿🇦

    We present our study of the differential cross section for the Higgs boson production in $k_T$-factorization framework. The $k_T$-factorization formalism includes a convolution over unintegrated parton distribution functions (uPDF) and off-shell parton level matrix element. The off-shell matrix element calculated considering initial gluons to be off-shell. We have considered only gluon fusion process which is dominant production mechanism for the Higgs boson production at LHC. We have used Ciafaloni-Catani-Fiorani-Marchesini (CCFM) uPDF based on CCFM evolution equations. We have compared our results with fixed order estimates up to NNLO+NNLL obtained using HRes tool within collinear factorization framework as well as with the ATLAS and CMS measurements of the corresponding differential distributions. This study will play an important role in understanding differential cross section within $k_T$-factorization framework.

    hep-phPoS(2017)·0 citations
20. 20*

    Non-perturbative gluon-hadron inputs for all available forms of QCD factorization

    B.I. Ermolaev🇷🇺 · S.I. Troyan🇷🇺

    Description of hadronic reactions at high energies is conventionally done on basis of QCD factoriza- tion so that factorization convolutions involve non-perturbative inputs mimicking non-perturbative contributions and perturbative evolution of those inputs. We construct the inputs for the gluon- hadron scattering amplitudes in the forward kinematics and, using the Optical theorem, convert them into inputs for gluon distributions in the both polarized and unpolarized hadrons. Firstly, we derive general mathematical criteria which any model for the inputs should obey and then suggest a Resonance Model satisfying those criteria. This model is inspired by a simple observation: after emitting an active parton off the hadron, the remaining ensemble of spectators becomes unstable and therefore it can be described through factors of the resonance type. Exploiting Resonance Model, we obtain non-perturbative inputs for gluon distributions in unpolarized and polarized hadrons for all available forms of QCD factorization: Basic, KT - and Collinear Factorizations. We compare the obtained inputs to the inputs available in the literature.

    hep-ph1 citation
21. 21*

    Complementarity Between Hyperkamiokande and DUNE

    Osamu Yasuda🇯🇵 · Shinya Fukasawa🇯🇵 · Monojit Ghosh🇯🇵

    In this talk we present our results on the sensitivity to the neutrino mass hierarchy, the octant of the mixing angle and the CP phase in the future long baseline experiments T2HK and DUNE as well as in the atmospheric neutrino observation at Hyperkamiokande (HK).

    hep-ph0 citations
22. 22*

    Nuclear and Quark Matter at High Temperature

    T.S.Biro🇭🇺 · A.Jakovac🇭🇺 · Z.Schram🇭🇺

    We review important ideas on nuclear and quark matter description on the basis of high- temperature field theory concepts, like resummation, dimensional reduction, interaction scale separation and spectral function modification in media. Statistical and thermodynamical concepts are spotted in the light of these methods concentrating on the - partially still open - problems of the hadronization process.

    hep-phnucl-thEPJA(2017)·7 citations
23. 23*

    Will atmospheric neutrino experiment at Hyper-Kamiokande see non-standard interaction effects?

    Osamu Yasuda🇯🇵

    In this talk we discuss the possibility to test the hypothesis, which has been proposed to explain the tension between the mass-squared differences of the solar neutrino and KamLAND experiments by the non-standard flavor-dependent interaction in neutrino propagation, with the atmospheric neutrino observations at the future Hyper-Kamiokande experiment.

    hep-ph1 citation
24. 24*

    Do fragmentation functions in factorization theorems correctly treat non-perturbative effects?

    John Collins🇺🇸

    Current all-orders proofs of factorization of hard processes are made by extracting the leading power behavior of Feynman graphs, i.e., by extracting asymptotics strictly order-by-order in perturbation theory. The resulting parton densities and fragmentation functions include non-perturbative effects. I show how there are missing elements in the proofs; these are related to and exemplified by string and cluster models of hadronization. The proofs rely on large rapidity differences between different parts of graphs for the process; but in reality large rapidity gaps are filled in

    hep-phPoS(2017)·5 citations
25. 25*

    Holographic QCD predictions for production and decay of pseudoscalar glueballs

    Frederic Brünner🇦🇹 · Anton Rebhan🇦🇹

    The top-down holographic Witten-Sakai-Sugimoto model for low-energy QCD, augmented by finite quark masses, has recently been found to be able to reproduce the decay pattern of the scalar glueball candidate f0(1710) on a quantitative level. In this Letter we show that this model predicts a narrow pseudoscalar glueball heavier than the scalar glueball and with a very restricted decay pattern involving eta or eta' mesons. Production should be either in pairs or in association with eta(') mesons. We discuss the prospect of discovery in high-energy hadron collider experiments through central exclusive production by comparing with eta' pair production.

    hep-phhep-thnucl-thPLB(2017)·24 citations
26. 26*

    Jet structure modifications in heavy-ion collisions with JEWEL

    Raghav Kunnawalkam Elayavalli🇺🇸

    Key features of jet-medium interactions in heavy-ion collisions are modifications to the jet structure. Recent results from experiments at the LHC and RHIC have motivated several theoretical calculations and monte carlo models towards predicting these observables simultaneously. In this report, the recoil picture in \textsc{Jewel} is summarized and two independent procedures through which background subtraction can be performed in \textsc{Jewel} are introduced. Information of the medium recoil in \textsc{Jewel} significantly improves its description of several jet shape measurements.

    ↳ nucl-thhep-phJ.Phys.Conf.Ser.(2017)·4 citations
27. 27*

    Impact of finite density on spectroscopic parameters of decuplet baryons

    K. Azizi🇹🇷 · N. Er🇹🇷 · H. Sundu🇹🇷

    The decuplet baryons, $\Delta$, ${\Sigma }^{\ast }$, ${\Xi }^{\ast }$ and ${\Omega }^{-}$, are studied in nuclear matter by using the in-medium QCD sum rules. By fixing the three momentum of the particles under consideration at the rest frame of the medium, the negative energy contributions are removed. It is obtained that the parameters of the $\Delta$ baryon are more affected by the medium against the ${\Omega }^{-}$ state, containing three strange quarks, whose mass and residue do not affected by the medium, considerably. We also find the vector and scalar self energies of these baryons in nuclear matter. By the recent progresses at $\bar{P}$ANDA experiment at FAIR and NICA facility it may be possible to study the in-medium properties of such states even the multi-strange ${\Xi }^{\ast }$ and ${\Omega }^{-}$ systems in near future.

    ↳ nucl-thhep-phPRD(2016)·11 citations
28. 28*

    Solar, supernova, atmospheric and geo neutrino studies using JUNO detector

    W.L. Guo🇨🇳 · R. Han🇨🇳 · Y.F. Li🇨🇳 · G. Salamanna🇮🇹

    Aside from its primary purpose of shedding light on the mass hierarchy (MH) using reactor anti-neutrinos, the JUNO experiment in Jiangmen (China) will also contribute to study neutrinos from non-reactor sources. In this poster we review JUNO's goals in the realms of supernova, atmospheric, solar and geo-neutrinos; present the related experimental issues and provide the current estimates of its potential. For a typical galactic SN at a distance of 10 kpc, JUNO will record about 5000 events from inverse beta decay, 2000 events from elastic neutrino-proton scattering, 300 events from neutrino-electron scattering, and the charged current and neutral current interactions on the ${}^{12}\mathrm{C}$ nuclei. For atmospheric neutrinos, JUNO should be able to detect ${\nu }_e$ and ${\nu }_{\mu }$ charged current events. Optimistically, a determination of the MH could be achieved at the 1.8$\sigma$ (2.6$\sigma$) level after 10 (20) years of data taking. JUNO will also study solar neutrinos from ${}^7\mathrm{Be}$ and ${}^8\mathrm{B}$, at low ($\approx$1 MeV) and higher energies respectively, to improve our understanding of the matter effects on the oscillation mechanism and of the solar metallicity. Challenges come primarily from the radioactive and cosmogenic backgrounds: the expected performance for two benchmark scintillator radio-purities, are shown. The flux of geo-neutrinos gives us an insight on the Earth composition and formation. We will show how the increased sample size given by JUNO's large sensitive mass of 20 KTon liquid scintillator will provide data to answer to several geological questions among which the U/Th ratio and mantle measurements.

    ↳ hep-exastro-ph.HEhep-phphysics.ins-detPoS(2017)·2 citations
29. 29*

    Thermal dynamics on the lattice with exponentially improved accuracy

    Jan Pawlowski🇩🇪 · Alexander Rothkopf🇩🇪

    We present a novel simulation prescription for thermal quantum fields on a lattice that operates directly in imaginary frequency space. By distinguishing initial conditions from quantum dynamics it provides access to correlation functions also outside of the conventional Matsubara frequencies ${\omega }_n=2\pi nT$. In particular it resolves their frequency dependence between $\omega =0$ and ${\omega }_1=2\pi T$, where the thermal physics $\omega \sim T$ of e.g.~transport phenomena is dominantly encoded. Real-time spectral functions are related to these correlators via an integral transform with rational kernel, so their unfolding is exponentially improved compared to Euclidean simulations. We demonstrate this improvement within a $0+1$-dimensional scalar field theory and show that spectral features inaccessible in standard Euclidean simulations are quantitatively captured.

    ↳ hep-latcond-mat.quant-gashep-phnucl-thPLB(2018)·14 citations
30. 30*

    Direct photon-hadron correlation measurement and a way towards photon-triggered jets at RHIC

    Nihar Ranjan Sahoo (For the STAR Collaboration)🇺🇸

    We report the results of ${\gamma }_{\mathrm{dir}}$ and ${\pi }^0$-hadron azimuthal correlations as a measure of the away-side jet-like correlated yields in central Au+Au and p+p collisions at $\sqrt{s_{{}_{NN}}}$=200 GeV in the STAR experiment. The charged-hadron per-trigger yields at mid-rapidity with respect to high-$p_T$ ${\gamma }_{\mathrm{dir}}$ and ${\pi }^0$ in central Au+Au collisions are compared with p+p collisions. Within uncertainties, the same $z_T$ (~$p_T^{\mathrm{assoc}}$ / $p_T^{\mathrm{trig}}$) dependence of the suppression is observed for ${\gamma }_{\mathrm{dir}}$ and ${\pi }^0$ - triggers. The results are compared with energy-loss model predictions. The $\gamma -\mathrm{jet}$ measurements can provide further understanding on the redistribution of in-medium energy loss. Ongoing $\gamma -\mathrm{jet}$ studies in the STAR experiment are also discussed.

    ↳ nucl-exhep-exhep-phJ.Phys.Conf.Ser.(2017)·0 citations
31. 31*

    Electromagnetic corrections to the leptonic decay rates of charged pseudoscalar mesons: lattice results

    V. Lubicz🇮🇹 · G. Martinelli🇮🇹 · C.T. Sachrajda🇬🇧 · F. Sanfilippo🇬🇧 · S. Simula🇮🇹 · N. Tantalo🇮🇹 · C. Tarantino🇮🇹

    Electromagnetic effects in the leptonic decay rates ${\pi }^{+}\to {\mu }^{+}\nu$ and $K^{+}\to {\mu }^{+}\nu$ are evaluated for the first time on the lattice. Following a method recently proposed in Ref. [1] the emission of virtual photons at leading order in the electromagnetic coupling is evaluated on the lattice and the infrared divergence computed for a point-like meson at finite lattice volume is subtracted. The physical decay rate is then obtained by adding the emission of real and virtual photons regularised with a photon mass. Using the gauge ensembles produced by the European Twisted Mass Collaboration with $N_f=2+1+1$ dynamical quarks the feasibility of our approach is demonstrated. Preliminary results for the electromagnetic corrections to charged (neutral) pion and kaon masses as well as to the leptonic decay rates of charged pions and kaons are presented.

    ↳ hep-lathep-phPoS(2016)·18 citations
32. 32*

    Masses and decay constants of $D_{(s)}^{\ast }$ and $B_{(s)}^{\ast }$ mesons in Lattice QCD with $N_f=2+1+1$ twisted-mass fermions

    V. Lubicz🇮🇹 · A. Melis🇮🇹 · S. Simula🇮🇹

    We present a lattice calculation of the decay constants and masses of $D_{(s)}^{\ast }$ and $B_{(s)}^{\ast }$ mesons using the gauge configurations produced by the European Twisted Mass Collaboration (ETMC) with $N_f=2+1+1$ dynamical quarks and at three values of the lattice spacing $a\sim 0.06-0.09$ fm. Pion masses are simulated in the range $m_{\pi }\sim 210-450$ MeV, while the strange and charm quark masses are close to their physical values. We computed the ratios of vector to pseudoscalar decay constants or masses for various values of the heavy-quark mass $m_h$ in the range $0.7m_c^{phys}\lesssim m_h\lesssim 3m_c^{phys}$. In order to reach the physical b-quark mass, we exploited the HQET prediction that, in the static limit of infinite heavy-quark mass, all the considered ratios are equal to one. We obtain: $f_{D^{\ast }}/f_D=1.078(36),$ $m_{D^{\ast }}/m_D=1.0769(79)$, $f_{D_s^{\ast }}/f_{D_s}=1.087(20)$, $m_{D_s^{\ast }}{m}_{D_s}=1.0751(56)$, $f_{B^{\ast }}/f_B=0.958(22)$, $m_{B^{\ast }}/m_B=1.0078(15)$, $f_{B_s^{\ast }}/f_{B_s}=0.974(10)$ and $m_{B_s^{\ast }}/m_{B_s}=1.0083(10)$. Combining them with the corresponding experimental masses from the PDG and the pseudoscalar decay constants calculated by ETMC, we get: $f_{D^{\ast }}=223.5(8.4)\mathrm{MeV}$, $m_{D^{\ast }}=2013(14)\mathrm{MeV}$, $f_{D_s^{\ast }}=268.8(6.6)\mathrm{MeV}$, $m_{D_s^{\ast }}=2116(11)\mathrm{MeV}$, $f_{B^{\ast }}=185.9(7.2)\mathrm{MeV}$, $m_{B^{\ast }}=5320.5(7.6)\mathrm{MeV}$, $f_{B_s^{\ast }}=223.1(5.4)\mathrm{MeV}$ and $m_{B_s^{\ast }}=5411.36(5.3)\mathrm{MeV}$.

    ↳ hep-lathep-phPoS(2017)·14 citations
33. 33*

    Limits on hadron spectrum from bulk medium properties

    Wojciech Broniowski🇵🇱

    We bring up the fact that the bulk thermal properties of the hadron gas, as measured on the lattice, preclude a very fast rising of the number of resonance states in the QCD spectrum, as assumed by the Hagedorn hypothesis, unless a substantial repulsion between hadronic resonances is present. If the Hagedorn growth continued above masses ~1.8 GeV, then the thermodynamic functions would noticeably depart from the measured lattice values at temperatures above 140 MeV, just below the transition temperature to quark-gluon plasma.

    ↳ nucl-thhep-phBled Workshops Phys.(2016)·3 citations
34. 34*

    Reconsidering seismological constraints on the available parameter space of macroscopic dark matter

    David Cyncynates🇺🇸 · Joshua Chiel🇺🇸 · Jagjit Sidhu🇺🇸 · Glenn D. Starkman🇺🇸

    Using lunar seismological data, constraints have been proposed on the available parameter space of macroscopic dark matter (macros). We show that actual limits are considerably weaker by considering in greater detail the mechanism through which macro impacts generate detectable seismic waves, which have wavelengths considerably longer than the diameter of the macro. We show that the portion of the macro parameter space that can be ruled out by current seismological evidence is considerably smaller than previously reported, and specifically that candidates with greater than or equal to nuclear density are not excluded by lunar seismology.

    ↳ astro-ph.COastro-ph.EPhep-phPRD(2017)·20 citations
35. 35*

    Asymptotically Safe Grand Unification

    Borut Bajc🇸🇮 · Francesco Sannino🇩🇰

    Phenomenologically appealing supersymmetric grand unified theories have large gauge representations and thus are not asymptotically free. Their ultraviolet validity is limited by the appearance of a Landau pole well before the Planck scale. One could hope that these theories save themselves, before the inclusion of gravity, by generating an interacting ultraviolet fixed point, similar to the one recently discovered in non-supersymmetric gauge-Yukawa theories. Employing a-maximization, a-theorem, unitarity bounds, as well as positivity of other central charges we nonperturbatively rule out this possibility for a broad class of prime candidates of phenomenologically relevant supersymmetric grand unified theories. We also uncover candidates passing these tests, which have either exotic matter or contain one field decoupled from the superpotential. The latter class of theories contains a model with the minimal matter content required by phenomenology.

    ↳ hep-thhep-lathep-phJHEP(2016)·60 citations
36. 36*

    Towards a quantitative understanding of high $p_T$ flow harmonics

    Jorge Noronha (Sao Paulo U.)🇧🇷

    In this proceedings I briefly review the recent progress achieved on the calculation of $v_n$ at high $p_T$ via the coupling of a jet energy loss model with full event-by-event viscous hydrodynamics. It is shown that that this framework can simultaneously describe experimental data for $R_{AA}$, $v_2$, and $v_3$ at high $p_T$. High $p_T$ $v_2$ is found to be approximately linearly correlated with the soft $v_2$ on an event-by-event basis, which opens up a new way to correlate soft and hard observables in heavy ion collisions.

    ↳ nucl-thhep-phnucl-exJ.Phys.Conf.Ser.(2017)·2 citations
37. 37*

    Proton radius from electron-proton scattering and chiral perturbation theory

    Marko Horbatsch🇨🇦 · Eric A. Hessels🇨🇦 · Antonio Pineda🇪🇸

    We determine the root-mean-square proton charge radius, $R_{\mathrm{p}}$, from a fit to low-$Q^2$ electron-proton elastic scattering cross section data with the higher moments fixed (within uncertainties) to the values predicted by chiral perturbation theory. We obtain $R_{\mathrm{p}}=0.857(11)$ fm. This number falls between the value obtained from muonic hydrogen analyses and the CODATA value (based upon atomic hydrogen spectroscopy and electron-proton scattering determinations).

    ↳ nucl-thhep-phnucl-exphysics.atom-phPRC(2017)·57 citations
38. 38*

    Mathematical aspects of the nuclear glory phenomenon: from backward focusing to Chebyshev polynomials

    Vladimir B. Kopeliovich (INR of RAS, Moscow & MIPT, Moscow)🇷🇺

    The angular dependence of the cumulative particles production off nuclei near the kinematical boundary for multistep process is defined by characteristic polynomials in angular variables $J_N^2(z_N^{\theta })$, where $\theta$ is the polar angle defining the momentum of the final (cumulative) particle, $z_N^{\theta }=cos(\theta /N)$, the integer $N$ being the multiplicity of the process (the number of interactions). Physical argumentation, exploring the small phase space method, leads to the appearance of equations for these polynomials $J_N^2[cos(\pi /N)]=0$. The recurrent relations between polynomials with different $N$ are obtained, and their connection with known in mathematics Chebyshev polynomials of 2-d kind is established. As a result of this equality, differential cross section of the cumulative particle production has characteristic behaviour $d\sigma \sim 1/\sqrt{\pi -\theta }$ at $\theta \sim \pi$ (the backward focusing effect). Such behaviour takes place for any multiplicity of the interaction, beginning with $n=3$, elastic or inelastic (with resonances excitations in intermediate states), and can be called the nuclear glory phenomenon, or 'Buddha's light' of cumulative particles.

    ↳ nucl-thhep-phJ.Phys.Conf.Ser.(2017)·1 citation
39. 39*

    Strongly coupled $\mathcal{N}=4$ super Yang-Mills plasma on the Coulomb branch I: Thermodynamics

    Kiminad A. Mamo🇺🇸

    We study $\mathcal{N}=4$ super Yang-Mills theory on the Coulomb branch (cSYM) in the strong coupling limit by using the AdS/CFT correspondence. The dual geometry is the rotating black 3-brane Type IIB supergravity solution with a single non-zero rotation parameter $r_0$ which sets a fixed mass scale corresponding to the scalar condensate $<\mathcal{O}>\sim r_0^4$ in the Coulomb branch. We introduce a new ensemble where $T$ and $<\mathcal{O}>$ are held fixed, i.e., the free energy $F(T,<\mathcal{O}>)$ is a function of $T$ and $<\mathcal{O}>$. We compute the equation of state (EoS) of $\mathcal{N}=4$ cSYM at finite $T$, as well as the heavy quark-antiquark potential and the quantized mass spectrums of the scalar and spin-2 glueballs at $T=0$. By computing the Wilson loop (minimal surface) at $T=0$, we determine the heavy quark-antiquark potential $V(L)$ to be the Cornell potential, which is confining for large separation $L$. At $T\ne 0$, we find two black hole branches: the large black hole and small black hole branches. For the large black hole branch, that has positive specific heat, we find qualitatively similar EoS to that of pure Yang-Mills theory on the lattice. For the small black hole branch, that has negative specific heat, we find an EoS where the entropy and energy densities decrease with $T$. We also find a second-order phase transition between the large and small black hole branches with critical temperature $T_c=T_{min}$.

    ↳ hep-thgr-qchep-phnucl-thPRD(2019)·5 citations
40. 40*

    Strongly coupled $\mathcal{N}=4$ super Yang-Mills plasma on the Coulomb branch II: Transport coefficients and hard probe parameters

    Kiminad A. Mamo🇺🇸

    We study $\mathcal{N}=4$ super Yang-Mills theory on the Coulomb branch (cSYM) by using its Type IIB supergravity dual. We compute the transport coefficients, and hard probe parameters of $\mathcal{N}=4$ cSYM at finite temperature $T$. We use the rotating black 3-brane solution of Type IIB supergravity with a single non-zero rotation parameter $r_0$ after analytically continuing $r_0\to -i{r}_0$, and in an ensemble where the Hawking temperature $T$ and a scalar condensate $<\mathcal{O}>\sim r_0^4$ are held fixed. We find that the bulk viscosity to entropy density ratio of the large black hole branch decreases with temperature and has a maxima around the critical temperature $T_c$ while, for the small black hole branch, it increases with temperature. The other transport coefficients and parameters of hard probes, such as the conductivity, jet quenching parameter, drag force, and momentum diffusion coefficients of the large black hole branch increase with temperature and asymptote to their conformal value while, for the small black hole branch, they decrease with temperature.

    ↳ hep-thhep-phnucl-thPRD(2019)·6 citations
41. 41*

    Physical effects involved in the measurements of neutrino masses with future cosmological data

    Maria Archidiacono🇩🇪 · Thejs Brinckmann🇩🇪 · Julien Lesgourgues🇩🇪 · Vivian Poulin🇫🇷

    Future Cosmic Microwave Background experiments together with upcoming galaxy and 21-cm surveys will provide extremely accurate measurements of different cosmological observables located at different epochs of the cosmic history. The new data will be able to constrain the neutrino mass sum with the best precision ever. In order to exploit the complementarity of the different redshift probes, a deep understanding of the physical effects driving the impact of massive neutrinos on CMB and large scale structures is required. The goal of this work is to describe these effects, assuming a summed neutrino mass close to its minimum allowed value. We find that parameter degeneracies can be removed by appropriate combinations, leading to robust and model independent constraints. A joint forecast of the sensitivity of Euclid and DESI surveys together with a CORE-like CMB experiment leads to a $1\sigma$ uncertainty of $14$~meV on the summed neutrino mass. However this particular combination gives rise to a peculiar degeneracy between $M_{\nu }$ and the optical depth at reionization. Independent constraints from 21-cm surveys can break this degeneracy and decrease the $1\sigma$ uncertainty down to $12$~meV.

    ↳ astro-ph.COhep-phJCAP(2017)·126 citations
42. 42*

    Initial conditions for hydrodynamics from weakly coupled pre-equilibrium evolution

    Aleksas Mazeliauskas🇺🇸

    We use leading order effective kinetic theory to simulate the pre\nobreakdash-equilibrium evolution of transverse energy and flow perturbations in heavy-ion collisions. We provide a Green function which propagates the initial perturbations of the energy-momentum tensor to a time when hydrodynamics becomes applicable. With this map, the pre-thermal evolution from saturated nuclei to hydrodynamics can be modeled in the framework of weakly coupled QCD.

    ↳ nucl-thhep-phJ.Phys.Conf.Ser.(2017)·0 citations
43. 43*

    Looking for Lorentz Violation in Short-Range Gravity

    Rui Xu🇺🇸

    General violations of Lorentz symmetry can be described by the Standard-Model Extension (SME) framework. The SME predicts modifications to existing physics and can be tested in high-precision experiments. By looking for small deviations from Newton gravity, short-range gravity experiments are expected to be sensitive to possible gravitational Lorentz-violation signals. With two group's short-range gravity data analyzed recently, no nonminimal Lorentz violation signal is found at the micron distance scale, which gives stringent constraints on nonminimal Lorentz-violation coefficients in the SME.

    ↳ gr-qchep-ph1 citation
44. 44*

    Susceptibilities from a black hole engineered EoS with a critical point

    Israel Portillo🇺🇸

    Currently at the Beam Energy Scan at RHIC experimental efforts are being made to find the QCD critical point. On the theoretical side, the behavior of higher-order susceptibilities of the net-baryon charge from Lattice QCD at ${\mu }_{{}_B}=0$ may allow us to estimate the position of the critical point in the QCD phase diagram. However, even if the series expansion continues to higher-orders, there is always the possibility to miss the critical point behavior due to truncation errors. An alternative approach is to use a black hole engineered holographic model, which displays a critical point at large densities and matches lattice susceptibilities at ${\mu }_{{}_B}=0$. Using the thermodynamic data from this black hole model, we obtain the freeze-out points extracted from the net-protons distribution measured at STAR and explore higher order fluctuations at the lowest energies at the beam energy scan to investigate signatures of the critical point.

    ↳ nucl-thhep-phJ.Phys.Conf.Ser.(2017)·7 citations
45. 45*

    Nonperturbative beta function of twelve-flavor SU(3) gauge theory

    Anna Hasenfratz🇺🇸 · David Schaich🇺🇸

    We study the discrete beta function of SU(3) gauge theory with Nf=12 massless fermions in the fundamental representation. Using an nHYP-smeared staggered lattice action and an improved gradient flow running coupling ${\tilde{g}}_c^2(L)$ we determine the continuum-extrapolated discrete beta function up to $g_c^2\approx 8.2$. We observe an IR fixed point at $g_{\star }^2=7.3\left({}_{-2}^{+8}\right)$ in the $c=\sqrt{8t}/L=0.25$ scheme, and $g_{\star }^2=7.3\left({}_{-3}^{+6}\right)$ with c=0.3, combining statistical and systematic uncertainties in quadrature. The systematic effects we investigate include the stability of the $(a/L)\to 0$ extrapolations, the interpolation of ${\tilde{g}}_c^2(L)$ as a function of the bare coupling, the improvement of the gradient flow running coupling, and the discretization of the energy density. In an appendix we observe that the resulting systematic errors increase dramatically upon combining smaller $c\lesssim 0.2$ with smaller $L\le 12$, leading to an IR fixed point at $g_{\star }^2=5.9(1.9)$ in the c=0.2 scheme, which resolves to $g_{\star }^2=6.9\left({}_{-1}^{+6}\right)$ upon considering only $L\ge 16$. At the IR fixed point we measure the leading irrelevant critical exponent to be ${\gamma }_g^{\star }=0.26(2)$, comparable to perturbative estimates.

    ↳ hep-lathep-phJHEP(2018)·70 citations
46. 46*

    Inflation from periodic extra dimensions

    Tetsutaro Higaki🇯🇵 · Yoshiyuki Tatsuta🇯🇵

    We discuss a realization of a small field inflation based on string inspired supergravities. In theories accompanying extra dimensions, compactification of them with small radii is required for realistic situations. Since the extra dimension can have a periodicity, there will appear (quasi-)periodic functions under transformations of moduli of the extra dimensions in low energy scales. Such a periodic property can lead to a UV completion of so-called multi-natural inflation model where inflaton potential consists of a sum of multiple sinusoidal functions with a decay constant smaller than the Planck scale. As an illustration, we construct a SUSY breaking model, and then show that such an inflaton potential can be generated by a sum of world sheet instantons in intersecting brane models on extra dimensions containing $T^2/{\mathbb{Z}}_2$ orbifold. We show also predictions of cosmic observables by numerical analyzes.

    ↳ hep-thhep-phJCAP(2017)·22 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.