Wed·Apr 6, 2016Wednesday·April 6, 2016

1. 01*

   Production of tau lepton pairs with high pT jets at the LHC and the TauSpinner reweighting algorithm

   J. Kalinowski🇵🇱 · W. Kotlarski🇩🇪 · E. Richter-Was🇵🇱 · Z. Was🇵🇱

   The TauSpinner algorithm allows to modify the physics of the Monte Carlo generated samples due to the changed assumptions of event production dynamics, without re-generating events. To each event it attributes weights: the spin effects of tau-lepton production or decay, or the production mechanism are modified. There is no need to repeat the detector response simulation. We document the extension to 2 to 4 processes in which the matrix elements for the parton-parton scattering amplitudes into a tau-lepton pair and two outgoing partons are used. Tree-level matrix elements for the Standard Model processes, including the Higgs boson production are used. Automatically generated codes by MadGraph5 have been adapted. Tests of the matrix elements, reweighting algorithm and numerical results are presented. For averaged tau lepton polarisation, we perform comparison of 2 to 2 and 2 to 4 matrix elements used to calculate the spin weight in pp to tau tau j j events. We show, that for events with tau-lepton pair close to the Z-boson peak, the tau-lepton polarisation calculated using 2 to 4 matrix elements is very close to the one calculated using 2 to 2 Born process only. For the m_(tautau) masses above the Z-boson peak, the effect from including 2 to 4 matrix elements is also marginal, however when restricting into subprocesses qq,q bar q to tau tau j j only, it can lead to a 10% difference on the predicted tau-lepton polarisation. Choice of electroweak scheme can have significant impact. The modification of the electroweak or strong interaction can be performed with the re-weighting technique. TauSpinner v.2.0.0, allows to introduce non-standard couplings for the Higgs boson and study their effects in the vector-boson-fusion. The discussion is relegated to forthcoming publications.

   hep-phhep-exEPJC(2016)·16 citations
2. 02*

   Comparison of associated Higgs boson-radion and Higgs boson pair production processes

   E. Boos🇷🇺 · S. Keizerov🇷🇺 · E. Rakhmetov🇷🇺 · K. Svirina🇷🇺

   Many models, in particular, the brane-world models with two branes, predict the existence of the scalar radion, whose mass can be somewhat smaller than those of all the Kaluza-Klein modes of the graviton and Standard Model (SM) particles. Due to its origin the radion interacts with the trace of the energy-momentum tensor of the SM. The fermion part of the radion interaction Lagrangian is different from that for the SM Higgs boson due to the presence of additional terms playing a role for off-shell fermions. It was shown previously that for the case of the single radion and single Higgs boson production processes in association with an arbitrary number of SM gauge bosons all the contributions to the perturbative amplitudes appearing due to these additional terms were cancelled out making the processes similar up to a replacement of masses and overall coupling constants. For the case of the associated Higgs boson-radion and the Higgs boson pair production processes involving the SM gauge bosons the similarity property also takes place. However a detailed consideration shows that in this case it is not enough to replace simply the masses and the constants ($m_h\to m_r$ and $v\to {\Lambda }_r$). One should also rescale the triple Higgs coupling by the factor $\xi \equiv 1+\frac{m_r^2-m_h^2}{3m_h^2}$.

   hep-phhep-thPRD(2016)·8 citations
3. 03*

   Diphoton excess and VV-scattering

   G.Cynolter🇭🇺 · J . Kovács🇭🇺 · E.Lendvai🇭🇺

   We consider minimal effective interactions of the 750 GeV mass resonance observed recently by ATLAS and CMS. Assuming a new scalar and gauge invariant effective interactions leads to non-trivial two particle scattering amplitudes with asymptotic gauge boson states. The longitudinally polarized $W\pm$ and $Z$ bosons interacting via dimension-five effective operators provide stringent constraints on the validity of the effective model. The large width found by ATLAS implying a bound of approximately 500 GeV already below the resonance, turns this scenario unlikely. For production mainly in gluon fusion we get an upper bound of $\sim 1.3$ TeV and strong limits on the masses of the underlying vector-like fermions are given.

   hep-phMod.Phys.Lett.A(2016)·9 citations
4. 04*

   One-loop Matching and Running with Covariant Derivative Expansion

   Brian Henning🇺🇸 · Xiaochuan Lu🇺🇸 · Hitoshi Murayama🇺🇸

   We develop tools for performing effective field theory (EFT) calculations in a manifestly gauge-covariant fashion. We clarify how functional methods account for one-loop diagrams resulting from the exchange of both heavy and light fields, as some confusion has recently arisen in the literature. To efficiently evaluate functional traces containing these "mixed" one-loop terms, we develop a new covariant derivative expansion (CDE) technique that is capable of evaluating a much wider class of traces than previous methods. The technique is detailed in an appendix, so that it can be read independently from the rest of this work. We review the well-known matching procedure to one-loop order with functional methods. What we add to this story is showing how to isolate one-loop terms coming from diagrams involving only heavy propagators from diagrams with mixed heavy and light propagators. This is done using a non-local effective action, which physically connects to the notion of "integrating out" heavy fields. Lastly, we show how to use a CDE to do running analyses in EFTs, \textit{i.e.} to obtain the anomalous dimension matrix. We demonstrate the methodologies by several explicit example calculations.

   hep-phhep-thJHEP(2018)·139 citations
5. 05*

   Soft gluon resummation for associated gluino-gaugino production at the LHC

   B. Fuks🇫🇷 · M. Klasen🇩🇪 · M. Rothering🇩🇪

   We perform a threshold resummation calculation for the associated production of gluinos and gauginos at the LHC to the next-to-leading logarithmic accuracy. Analytical results are presented for the process-dependent soft anomalous dimension and the hard function. The resummed results are matched to a full next-to-leading order calculation, for which we have generalised the previously known results to the case of supersymmetric scenarios featuring non-universal squark masses. Numerically, the next-to-leading logarithmic contributions increase the total next-to-leading order cross section by 7 to 20% for central scale choices and gluino masses of 3 to 6 TeV, respectively, and reduce its scale dependence typically from up to $\pm 12$% to below $\pm 3$%.

   hep-phhep-exJHEP(2016)·17 citations
6. 06*

   Physics from solar neutrinos in dark matter direct detection experiments

   David G. Cerdeno (IPPP, Durham U.)🇬🇧 · Malcolm Fairbairn (King's Coll. London)🇬🇧 · Thomas Jubb (IPPP, Durham U.)🇬🇧 · Pedro A. N. Machado (Madrid, IFT and Madrid, Autonoma U.)🇪🇸 · Aaron C. Vincent (IPPP, Durham U.)🇬🇧 · Celine Boehm (IPPP, Durham U. and Annecy, LAPTH)🇬🇧

   The next generation of dark matter direct detection experiments will be sensitive to both coherent neutrino-nucleus and neutrino-electron scattering. This will enable them to explore aspects of solar physics, perform the lowest energy measurement of the weak angle to date, and probe contributions from new theories with light mediators. In this article, we compute the projected nuclear and electron recoil rates expected in several dark matter direct detection experiments due to solar neutrinos, and use these estimates to quantify errors on future measurements of the neutrino fluxes, weak mixing angle and solar observables, as well as to constrain new physics in the neutrino sector. Our analysis shows that the combined rates of solar neutrino events in second generation experiments (SuperCDMS and LZ) can yield a measurement of the $pp$ flux to 2.5% accuracy via electron recoil, and slightly improve the ${}^8$B flux determination. Assuming a low-mass argon phase, projected tonne-scale experiments like DARWIN can reduce the uncertainty on both the $pp$ and boron-8 neutrino fluxes to below 1%. Finally, we use current results from LUX, SuperCDMS and CDMSlite to set bounds on new interactions between neutrinos and electrons or nuclei, and show that future direct detection experiments can be used to set complementary constraints on the parameter space associated with light mediators.

   hep-phJHEP(2016)·170 citations
7. 07*

   p-wave Annihilating Dark Matter from a Decaying Predecessor and the Galactic Center Excess

   Jeremie Choquette🇨🇦 · James M. Cline🇨🇦 · Jonathan M. Cornell🇨🇦

   Dark matter (DM) annihilations have been widely studied as a possible explanation of excess gamma rays from the galactic center seen by Fermi/LAT. However most such models are in conflict with constraints from dwarf spheroidals. Motivated by this tension, we show that p-wave annihilating dark matter can easily accommodate both sets of observations due to the lower DM velocity dispersion in dwarf galaxies. Explaining the DM relic abundance is then challenging. We outline a scenario in which the usual thermal abundance is obtained through s-wave annihilations of a metastable particle, that eventually decays into the p-wave annihilating DM of the present epoch. The couplings and lifetime of the decaying particle are constrained by big bang nucleosynthesis, the cosmic microwave background and direct detection, but significant regions of parameter space are viable. A sufficiently large p-wave cross section can be found by annihilation into light mediators, that also give rise to Sommerfeld enhancement. A prediction of the scenario is enhanced annihilations in galaxy clusters.

   hep-phastro-ph.COastro-ph.HEPRD(2016)·37 citations
8. 08*

   Lab-based limits on the Carroll-Field-Jackiw Lorentz-violating electrodynamics

   Y.M.P. Gomes🇧🇷 · P.C. Malta🇧🇷

   The CPT-odd and Lorentz-violating Carroll-Field-Jackiw modification of electrodynamics is discussed and we study its effects on the energy spectrum of hydrogen, as well as in the generation of a momentum-dependent electric dipole moment for charged leptons. We also briefly comment on the possibility of the detection of Lorentz violation in measurements of vacuum birefringence in resonant cavities. The bounds found are based on local laboratory experimental limits and are not competitive with the ones coming from astrophysical considerations.

   hep-phPRD(2016)·54 citations
9. 09*

   A Visible QCD Axion from an Enlarged Color Group

   Tony Gherghetta🇺🇸 · Natsumi Nagata🇺🇸 · Mikhail Shifman🇺🇸

   We consider the possibility of an enlarged QCD color group, SU(3+$N^{\prime }$) spontaneously broken to SU(3)${}_c\times$SU($N^{\prime }$) with extra vector-like quarks transforming in the fundamental representation. When the heavy quarks are integrated out below the PQ-breaking scale, they generate an axion coupling which simultaneously solves the strong CP problem for both gauge groups. However, the axion mass now receives a new nonperturbative contribution from the SU($N^{\prime }$) confinement scale, which can be substantially larger than the QCD scale. This can increase the axion mass to be at or above the electroweak scale. This visible axion can then decay into gluons and photons giving rise to observable signals at Run-II of the LHC. In particular, if the mass is identified with the 750 GeV diphoton resonance then the new confinement scale is $\sim$ TeV and the PQ-breaking scale is $\sim$ 10 TeV. This predicts vector-like quarks and a PQ scalar resonance in the multi-TeV range, with the possibility that dark matter is an SU($N^{\prime }$) baryon.

   hep-phhep-thPRD(2016)·138 citations
10. 10*

    Top-quark pole mass in the tadpole-free MS-bar scheme

    Stephen P. Martin🇺🇸

    The complex pole mass of the top quark is presented at full two-loop order in the Standard Model, augmenting the known four-loop QCD contributions. The input parameters are the MS-bar Yukawa and gauge couplings, the Higgs self-coupling, and the Higgs vacuum expectation value (VEV). Here, the VEV is defined as the minimum of the full effective potential in Landau gauge, so that tadpoles vanish. This is an alternative to earlier results that instead minimize the tree-level potential, resulting in a VEV that is gauge-fixing independent but accompanied by negative powers of the Higgs self-coupling in perturbative expansions. The effects of non-zero Goldstone boson mass are eliminated by resummation. I also study the renormalization scale dependence of the calculated pole mass.

    hep-phPRD(2016)·34 citations
11. 11*

    Gauge $U(1)$ Dark Symmetry and Radiative Light Fermion Masses

    Corey Kownacki🇺🇸 · Ernest Ma🇺🇸

    A gauge $U(1)$ family symmetry is proposed, spanning the quarks and leptons as well as particles of the dark sector. The breaking of $U(1)$ to $Z_2$ divides the two sectors and generates one-loop radiative masses for the first two families of quarks and leptons, as well as all three neutrinos. We study the phenomenological implications of this new connection between family symmetry and dark matter. In particular, a scalar or pseudoscalar particle associated with this $U(1)$ breaking may be identified with the 750 GeV diphoton resonance recently observed at the Large Hadron Collider (LHC).

    hep-phPLB(2016)·33 citations
12. 12*

    Anomalous Top and Bottom Yukawa Couplings and LHC Run 1 Data

    Nobuhito Maru🇯🇵 · Nobuchika Okada🇺🇸

    In some extensions of the Standard Model, Yukawa couplings of the physical Higgs boson can be deviated from those in the Standard Model. We study a possibility whether or not such anomalous Yukawa couplings are consistent with the LHC Run 1 data. It is found that sizable deviations of top and bottom (and tau) Yukawa couplings from the Standard Model predictions can nicely fit the data. New physics beyond the Standard Model can be revealed through more precise measurements of such anomalous Yukawa couplings at the LHC Run 2 in the near future. We also discuss a simple setup which can leads to anomalous Yukawa couplings.

    hep-ph4 citations
13. 13*

    Multiparticle production: an old-fashioned view

    V.A. Schegelsky🇷🇺 · M.G. Ryskin🇷🇺

    We consider the dynamics of high energy multiparticle production and discuss how the space-time picture of inelastic interaction may reveal itself in identical particles Bose-Einstein correlations.

    hep-ph2 citations
14. 14*

    $D_{s0}^{\ast }(2317)$ and $DK$ scattering in $B$ decays from BaBar and LHCb data

    Miguel Albaladejo🇪🇸 · Daisuke Jido🇯🇵 · Juan Nieves🇪🇸 · Eulogio Oset🇪🇸

    We study the experimental $DK$ invariant mass spectra of the reactions $B^{+}\to {\bar{D}}^0{D}^0{K}^{+}$, $B^0\to D^{-}{D}^0{K}^{+}$ (measured by the BaBar Collaboration) and $B_s\to {\pi }^{+}{\bar{D}}^0{K}^{-}$ (measured by the LHCb Collaboration), where an enhancement right above the threshold is seen. We show that this enhancement is due to the presence of $D_{s0}^{\ast }(2317)$, which is a $DK$ bound state in the $I(J^P)=0(0^{+})$ sector. We employ a unitarized amplitude with an interaction potential fixed by heavy meson chiral perturbation theory. We obtain a mass $M_{D_{s0}^{\ast }}=2315_{-17}^{+12}{}_{-5}^{+10}\text{MeV}$, and we also show, by means of the Weinberg compositeness condition, that the $DK$ component in the wave function of this state is $P_{DK}=70_{-6}^{+4}{}_{-8}^{+4}\%$, where the first (second) error is statistical (systematic).

    hep-phEPJC(2016)·59 citations
15. 15*

    Complex Scaling in Neutrino Mass Matrix

    Rome Samanta🇮🇳 · Probir Roy🇮🇳 · Ambar Ghosal🇮🇳

    Using the residual symmetry approach, we propose a complex extension of the scaling ansatz on $M_{\nu }$ which allows a nonzero mass for each of the three light neutrinos as well as a nonvanishing ${\theta }_{13}$. Leptonic Dirac CP violation must be maximal while atmospheric neutrino mixing need not to be exactly maximal. Each of the two Majorana phases, to be probed by the search for $0\nu \beta \beta$ decay, has to be zero or $\pi$ and a normal neutrino mass hierarchy is allowed.

    hep-phActa Phys.Polon.Supp.(2016)·9 citations
16. 16*

    Mini Force: the (B-L) + xY gauge interaction with a light mediator

    Hye-Sung Lee🇰🇷 · Seokhoon Yun🇰🇷

    The relevant phenomenology and the best search schemes of a subelectroweak-scale gauge boson can be vastly different depending on its coupling. For instance, the rare decay into a light gauge boson and the high precision parity test can be sensitive if it has an axial coupling. The minimal gauge extension of the standard model with the U(1)_{B-L + xY} requires only three right-handed neutrinos, well-suited to the current neutrino mass and mixing data, and no additional exotic matter fields. We study the light gauge boson of this symmetry in detail including its axial coupling property from the hypercharge shift.

    hep-phPRD(2016)·21 citations
17. 17*

    QCD topological susceptibility from the nonlocal chiral quark model

    Seung-il Nam🇰🇷 · Chung-Wen Kao🇹🇼

    We investigate the QCD topological susceptibility ${\chi }_t$ by using the nonlocal chiral quark model (NL$\chi$QM). This model is based on the liquid instanton QCD-vacuum configuration in which $\mathrm{SU}(3)$ flavor symmetry is explicitly broken by the current quark mass $(m_{u,d},m_s)\approx (5,135)$ MeV. To compute ${\chi }_t$, the local topological charge density operator $Q_t(x)$ is derived from the effective partition function of NL$\chi$QM. We take into account the contributions from the leading-order (LO) ones $\sim \mathcal{O}(N_c)$ in the $1/N_c$ expansion. We also verify that the analytical expression of ${\chi }_t$ in NL$\chi$QM satisfy the Witten-Veneziano (WV) and the Leutwyler-Smilga (LS) formulae. Once the average instanton size and inter-instanton distance are fixed with $\bar{\rho }=1/3$ fm and $\bar{R}=1$ fm, respectively, all the associated model parameters are all determined self-consistently within the model, including the $\eta$ and ${\eta }^{\prime }$ weak decay constants. We obtain the results such as $F_{\eta }=96.77$ MeV and $F_{{\eta }^{\prime }}=102.53$ MeV for instance. Numerically we observe that ${\chi }_t=(165.57\mathrm{MeV}{)}^4$ in our full calculation. This value is comparable with its empirical one ${\chi }_t=(175\pm 5\mathrm{MeV}{)}^4$. We also find that our ${\chi }_t^{\mathrm{WV}}={\chi }_t^{\mathrm{QL}}=(194.30,\mathrm{MeV}{)}^4$ in the quenched limit and ${\chi }_t^{\mathrm{LS}}=(162.54\mathrm{MeV}{)}^4$ in the chiral limit. Consequently, we conclude that ${\chi }_t<{\chi }_t^{\mathrm{QL}}$. Our result also implies that the $(10\sim 20)\%$ decrease with the dynamical quark contributions.

    hep-phhep-latnucl-thJ.Korean Phys.Soc.(2017)·0 citations
18. 18*

    QCD Axion as a Bridge Between String Theory and Flavor Physics

    Y. H. Ahn🇰🇷

    We construct a string-inspired model, motivated by the flavored Peccei-Quinn (PQ) axions, as a useful bridge between flavor physics and string theory. The key feature is two anomalous gauged $U(1)$ symmetries, responsible for both the fermion mass hierarchy problem of the standard model and the strong CP problem, that combine string theory with flavor physics and severely constrain the form of the F- and D-term contributions to the potential. In the context of supersymmetric moduli stabilization we stabilize the size moduli with positive masses while leaving two axions massless and one axion massive. We demonstrate that, while the massive gauge bosons eat the two axionic degrees of freedom, two axionic directions survive to low energies as the flavored PQ axions.

    hep-phhep-thPRD(2016)·13 citations
19. 19*

    Fun with higher-loop Feynman diagrams

    Thomas Luthe🇩🇪 · York Schroder🇨🇱

    We review recent progress that we have achieved in evaluating the class of fully massive vacuum integrals at five loops. After discussing topics that arise in classification, evaluation and algorithmic codification of this specific set of Feynman integrals, we present some selected new results for their expansions around $4-2\epsilon$ dimensions.

    hep-phJ.Phys.Conf.Ser.(2016)·10 citations
20. 20*

    The Hagedorn-type structure of the non-perturbative gluon pressure within the mass gap approach to QCD

    V. Gogokhia🇭🇺 · A. Shurgaia🇬🇪 · M. Vasuth🇭🇺

    We have shown in detail that the low-temperature expansion for the non-perturbative gluon pressure has the Hagedorn-type structure. Its exponential spectrum of all the effective gluonic excitations are expressed in terms of the mass gap. It is this which is responsible for the large-scale dynamical structure of the QCD ground state. The non-perturbative gluon pressure properly scaled has a maximum at some characteristic temperature $T=T_c=266.5\text{MeV}$, separating the low- and high temperature regions. It is exponentially suppressed in the $T\to 0$ limit. In the $T\to T_c$ limit it demonstrates an exponential rise in the number of dynamical degrees of freedom. Its exponential increase behavior with temperature is valid only up to $T_c$. This makes it possible to identify $T_c$ with the Hagedorn-type transition temperature $T_h$, i.e., to put $T_h=T_c$ within the mass gap approach to QCD at finite temperature. The non-perturbative gluon pressure has a complicated dependence on the mass gap and temperature near $T_c$ and up to approximately $(4-5)T_c$. In the limit of very high temperatures $T\to \infty$ its polynomial character is confirmed, containing the terms proportional to $T^2$ and $T$, multiplied by the corresponding powers of the mass gap. \end{abstract}

    hep-ph0 citations
21. 21*

    Analyses of whole transverse momentum distributions in $p\bar{p}$ and $pp$ collisions by using a modified version of Hagedorn's formula

    Takuya Mizoguchi🇯🇵 · Minoru Biyajima🇯🇵 · Naomichi Suzuki🇯🇵

    To describe the transverse distribution of charged hadrons at 1.96 TeV observed by the CDF collaboration, we propose a formula with two component, namely, hadron gas distributions and inverse power laws. The data collected at 0.9, 2.76, 7, and 13 TeV by the ALICE, CMS, and ATLAS collaborations are also analyzed using various models including single component models as well as two component models. The results by using modified version of Hagedorn's formula are compared with those by using the two component model proposed by Bylinkin, Rostovtsev and Ryskin (BRR). Moreover, we show that there is an interesting interrelation among our the modified version of Hagedorn's formula, a formula proposed by ATLAS collaboration, and the BRR formula.

    hep-phInt.J.Mod.Phys.A(2017)·46 citations
22. 22*

    Single and double inclusive forward jet production at the LHC at $\sqrt{s}$ = 7 and 13 TeV

    Marcin Bury🇵🇱 · Michal Deak🇵🇱 · Krzysztof Kutak🇵🇱 · Sebastian Sapeta🇵🇱

    We provide a description of the transverse momentum spectrum of single inclusive forward jets produced at the LHC, at the center-of-mass energies of 7 and 13 TeV, using the high energy factorization (HEF) framework. We subsequently study double inclusive forward jet production and, in particular, we calculate contributions to azimuthal angle distributions coming from double parton scattering. We also compare our results for double inclusive jet production to those obtained with the Pythia Monte Carlo generator. This comparison confirms that the HEF resummation acts like an initial state parton shower. It also points towards the need to include final state radiation effects in the HEF formalism.

    hep-phhep-exPLB(2016)·18 citations
23. 23*

    Progress in constraining axion and non-Newtonian gravity from the Casimir effect

    V. M. Mostepanenko🇷🇺

    We consider recent progress in constraining the axion-nucleon coupling constants and the Yukawa-type corrections to Newtonian gravity from experiments on measuring the Casimir interaction. After a brief review of previously obtained constraints, we concentrate on the new Casimir-less experiment, which allows to strengthen the known results up to factors of 60 and 1000 for the axion-like particles and Yukawa-type corrections, respectively. We also discuss possibilities allowing to further strengthen the constraints on axion-nucleon coupling constants, and propose a new experiment aiming to achieve this goal.

    hep-phgr-qcInt.J.Mod.Phys.A(2016)·9 citations
24. 24*

    The High-Energy Tail of the Galactic Center Gamma-Ray Excess

    Tim Linden🇺🇸 · Nicholas L. Rodd🇺🇸 · Benjamin R. Safdi🇺🇸 · Tracy R. Slatyer🇺🇸

    Observations by the Fermi-LAT have uncovered a bright, spherically symmetric excess surrounding the center of the Milky Way galaxy. The spectrum of the gamma-ray excess peaks sharply at an energy ~2 GeV, exhibiting a hard spectrum at lower energies, and falls off quickly above an energy ~5 GeV. The spectrum of the excess above ~10 GeV is potentially an important discriminator between different physical models for its origin. We focus our study on observations of the gamma-ray excess at energies exceeding 10 GeV, finding: (1) a statistically significant excess remains in the energy range 9.5-47.5 GeV, which is not degenerate with known diffuse emission templates such as the Fermi Bubbles, (2) the radial profile of the excess at high energies remains relatively consistent with data near the spectral peak, (3) the data above ~5 GeV prefer a slightly greater ellipticity with a major axis oriented perpendicular to the Galactic plane. Using the recently developed non-Poissonian template fit, we find mild evidence for a point-source origin for the high-energy excess, although given the statistical and systematic uncertainties we show that a smooth origin of the high-energy emission cannot be ruled out. We discuss the implication of these findings for pulsar and dark matter models of the gamma-ray excess. Finally we provide a number of updated measurements of the gamma-ray excess, utilizing novel diffuse templates and the Pass 8 dataset.

    ↳ astro-ph.HEhep-phPRD(2016)·89 citations
25. 25*

    Jet-like Correlations with Direct-Photon and Neutral-Pion Triggers at $\sqrt{s_{{}_{NN}}}=200$ GeV

    STAR Collaboration

    Azimuthal correlations of charged hadrons with direct-photon (${\gamma }_{dir}$) and neutral-pion (${\pi }^0$) trigger particles are analyzed in central Au+Au and minimum-bias $p+p$ collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV in the STAR experiment. The charged-hadron per-trigger yields at mid-rapidity from central Au+Au collisions are compared with $p+p$ collisions to quantify the suppression in Au+Au collisions. The suppression of the away-side associated-particle yields per ${\gamma }_{dir}$ trigger is independent of the transverse momentum of the trigger particle ($p_T^{\mathrm{trig}}$), whereas the suppression is smaller at low transverse momentum of the associated charged hadrons ($p_T^{\mathrm{assoc}}$). Within uncertainty, similar levels of suppression are observed for ${\gamma }_{dir}$ and ${\pi }^0$ triggers as a function of $z_T$ ($\equiv p_T^{\mathrm{assoc}}/p_T^{\mathrm{trig}}$). The results are compared with energy-loss-inspired theoretical model predictions. Our studies support previous conclusions that the lost energy reappears predominantly at low transverse momentum, regardless of the trigger energy.

    ↳ nucl-exhep-exhep-phnucl-thPLB(2016)·91 citations
26. 26*

    Instanton-torus knot duality in 5d SQED and $SU(2)$ SQCD

    A. Gorsky🇷🇺

    We briefly review the instanton-torus knot duality found in 5d SUSY gauge theories with one compact dimension. The fermion condensate turn out to be the generating function for the torus knot polynomials colored by the fundamental representation.

    ↳ hep-thcond-mat.str-elhep-phmath-ph+11 citation
27. 27*

    Thermal production of charm quarks in heavy ion collisions at Future Circular Collider

    Yunpeng Liu🇺🇸 · Che-Ming Ko🇺🇸

    By solving the rate equation in an expanding quark-gluon plasma, we study thermal production of charm quarks in central Pb+Pb collisions at the Future Circular Collider. With the charm quark production cross section taken from the perturbative QCD at the next-to-leading order, we find that charm quark production from the quark-gluon plasma can be appreciable compared to that due to initial hard scattering between colliding nucleons.

    ↳ nucl-thhep-phJ.Phys.G(2016)·10 citations
28. 28*

    Plane density of induced vacuum charge in a supercritical Coulomb potential

    V.R. Khalilov🇷🇺 · I.V. Mamsurov🇷🇺

    An expression for the density of a planar induced vacuum charge is obtained in a strong Coulomb potential in coordinate space. Treatment is based on a self-adjoint extension approach for constructing of the Green's function of a charged fermion in this potential. Induced vacuum charge density is calculated and analyzed at the subcritical and supercritical Coulomb potentials for massless and massive fermions. The behavior of the obtained vacuum charge density is investigated at long and short distances from the Coulomb center. The induced vacuum charge has a screening sign. Screening of a Coulomb impurity in graphene is briefly discussed. We calculate the real vacuum polarization charge density that acquires the quantum electrodynamics vacuum in the supercritical Coulomb potential due to the so-called real vacuum polarization. It is shown that the vacuum charge densities essentially differ in massive and massless cases. We expect that our results can, as a matter of principle, be tested in graphene with a supercritical Coulomb impurity.

    ↳ hep-thhep-phquant-phPLB(2017)·6 citations
29. 29*

    Limits on the effective quark radius from inclusive $ep$ scattering at HERA

    ZEUS Collaboration: H. Abramowicz🇮🇱 · I. Abt🇩🇪 · L. Adamczyk🇵🇱 · M. Adamus🇵🇱 · S. Antonelli🇮🇹 · V. Aushev🇺🇦 · O. Behnke🇩🇪 · U. Behrens🇩🇪 · A. Bertolin🇮🇹 · S. Bhadra🇨🇦 · I. Bloch🇩🇪 · E.G. Boos🇰🇿 and 115 other authors

    The high-precision HERA data allows searches up to TeV scales for Beyond the Standard Model contributions to electron-quark scattering. Combined measurements of the inclusive deep inelastic cross sections in neutral and charged current $ep$ scattering corresponding to a luminosity of around 1 fb${}^{-1}$ have been used in this analysis. A new approach to the beyond the Standard Model analysis of the inclusive $ep$ data is presented; simultaneous fits of parton distribution functions together with contributions of "new physics" processes were performed. Results are presented considering a finite radius of quarks within the quark form-factor model. The resulting 95% C.L. upper limit on the effective quark radius is $0.43\cdot 10^{-16}$ cm.

    ↳ hep-exhep-phPLB(2016)·23 citations
30. 30*

    Power Counting and Wilsonian Renormalization in Nuclear Effective Field Theory

    Manuel Pavon Valderrama🇨🇳

    Effective field theories are the most general tool for the description of low energy phenomena. They are universal and systematic: they can be formulated for any low energy systems we can think of and offer a clear guide on how to calculate predictions with reliable error estimates, a feature that is called power counting. These properties can be easily understood in Wilsonian renormalization, in which effective field theories are the low energy renormalization group evolution of a more fundamental ---perhaps unknown or unsolvable--- high energy theory. In nuclear physics they provide the possibility of a theoretically sound derivation of nuclear forces without having to solve quantum chromodynamics explicitly. However there is the problem of how to organize calculations within nuclear effective field theory: the traditional knowledge about power counting is perturbative but nuclear physics is not. Yet power counting can be derived in Wilsonian renormalization and there is already a fairly good understanding of how to apply these ideas to non-perturbative phenomena and in particular to nuclear physics. Here we review a few of these ideas, explain power counting in two-nucleon scattering and reactions with external probes and hint at how to extend the present analysis beyond the two-body problem.

    ↳ nucl-thhep-phIJMPE(2016)·49 citations
31. 31*

    Influence of ~7 keV sterile neutrino dark matter on the process of reionization

    Anton Rudakovskyi🇺🇦 · Dmytro Iakubovskyi🇺🇦

    Recent reports of a weak unidentified emission line at ~3.5 keV found in spectra of several matter-dominated objects may give a clue to resolve the long-standing problem of dark matter. One of the best physically motivated particle candidate able to produce such an extra line is sterile neutrino with the mass of ~7 keV. Previous works show that sterile neutrino dark matter with parameters consistent with the new line measurement modestly affects structure formation compared to conventional cold dark matter scenario. In this work, we concentrate for the first time on contribution of the sterile neutrino dark matter able to produce the observed line at ~3.5 keV, to the process of reionization. By incorporating dark matter power spectra for ~7 keV sterile neutrinos into extended semi-analytical 'bubble' model of reionization we obtain that such sterile neutrino dark matter would produce significantly sharper reionization compared to widely used cold dark matter models, impossible to 'imitate' within the cold dark matter scenario under any reasonable choice of our model parameters, and would have a clear tendency of lowering both the redshift of reionization and the electron scattering optical depth (although the difference is still below the existing model uncertainties). Further dedicated studies of reionization (such as 21 cm measurements or studies of kinetic Sunyaev-Zeldovich effect) will thus be essential for reconstruction of particle candidate responsible the ~3.5 keV line.

    ↳ astro-ph.COastro-ph.HEhep-phJCAP(2016)·17 citations
32. 32*

    Influence of Electric Charge and Modified Gravity on Density Irregularities

    M. Zaeem Ul Haq Bhatti🇵🇰 · Z. Yousaf🇵🇰

    This work aims to identify some inhomogeneity factors for plane symmetric topology with anisotropic and dissipative fluid under the effects of both electromagnetic field as well as Palatini $f(R)$ gravity. We construct the modified field equations, kinematical quantities and mass function to continue our analysis. We have explored the dynamical quantities, conservation equations and modified Ellis equations with the help of a viable $f(R)$ model. Some particular cases are discussed with and without dissipation to investigate the corresponding inhomogeneity factors. For non-radiating scenario, we examine such factors with dust, isotropic and anisotropic matter in the presence of charge. For dissipative fluid, we investigate the inhomogeneity factor with charged dust cloud. We conclude that electromagnetic field increases the inhomogeneity in matter while the extra curvature terms make the system more homogeneous with the evolution of time.

    ↳ gr-qcastro-ph.COhep-phhep-thEPJC(2016)·60 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.