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We use functional methods to match the Two-Higgs Doublet Model with heavy scalars in the nondecoupling regime to the appropriate nonlinear effective field theory, which takes the form of an electroweak chiral Lagrangian (HEFT). The effective Lagrangian is derived to leading order in the chiral counting. This includes the loop induced $h\to\gamma\gamma$ and $h\to Z\gamma$ local terms, which enter at the same chiral order as their counterparts in the Standard Model. An algorithm is presented that allows us to compute the coefficient functions to all orders in $h$. Some of the all-orders results are given in closed form. The parameter regimes for decoupling, nondecoupling and alignment scenarios in the effective field theory context and some phenomenological implications are briefly discussed., Comment: 20 pages, no figures; v2: paragraph on custodial symmetry breaking and further references added, matches published version

We present a calculation of direct photon production at next-to-leading order of QCD and a matching of this calculation with parton showers using POWHEG BOX. Based on simulations with POWHEG+PYTHIA, we perform a detailed phenomenological analysis of PHENIX data on prompt photon production and photon-hadron jet correlations in pp collisions at RHIC, considerably improving the description of these data with respect to previous calculations, and we suggest additional interesting analyses., Comment: 25 pages, 8 figures

We present a systematic theoretical analysis of the ALICE measurement of low-$p_T$ direct-photon production in central lead-lead collisions at the LHC with a centre-of-mass energy of $\sqrt{s_{NN}}=2.76$ TeV. Using next-to-leading order of perturbative QCD, we compute the relative contributions to prompt-photon production from different initial and final states and the theoretical uncertainties coming from independent variations of the renormalisation and factorisation scales, the nuclear parton densities and the fragmentation functions. Based on different fits to the unsubtracted and prompt-photon subtracted ALICE data, we consistently find an exponential, possibly thermal, photon spectrum from the quark-gluon plasma (or hot medium) with slope $T=304\pm 58$ MeV and $309\pm64$ MeV at $p_T\in[0.8;2.2]$ GeV and $p_T\in[1.5;3.5]$ GeV as well as a power-law ($p_T^{-4}$) behavior for $p_T>4$ GeV as predicted by QCD hard scattering., Comment: 4 pages, 5 figures, proceedings of ICHEP 2014

Thermal photons radiated in heavy-ion collisions represent an important signal for a recently discovered new state of matter, the deconfined quark-gluon plasma. However, a clean identification of this signal requires precise knowledge of the prompt photons produced simultaneously in hard collisions of quarks and gluons, mostly through their fragmentation. In this paper, we demonstrate that PHENIX data on photons produced in proton-proton collisions with low transverse momenta allow to extract new information on this fragmentation process. While existing data do not yet convincingly favor one parameterization (BFG II) over the two other frequently used photon fragmentation functions (BFG I and GRV NLO), the data sets recorded by PHENIX and STAR at BNL RHIC in 2013 with tenfold higher statistics should allow for such an analysis., Comment: 5 pages, 3 figures, 1 table

In this article, we investigate the potential of low-mass lepton pair production in proton-ion collisions at the LHC to constrain nuclear modifications of parton densities. Similarly to prompt photon production, the transverse momentum spectrum is shown to be dominated by the QCD Compton process, but has virtually no fragmentation or isolation uncertainties. Depending on the orientation of the proton and ion beams and on the use of central or forward detector components, all interesting regions of nuclear effects (shadowing, antishadowing, isospin and EMC effects) can be probed. Ratios of cross sections allow to eliminate theoretical scale and bare-proton parton density errors as well as many experimental systematic uncertainties., Comment: 16 pages, 8 figures

We present a rigorous theoretical analysis of the ALICE measurement of low-p_T direct-photon production in central lead-lead collisions at the LHC with a centre-of-mass energy of \sqrt{s_{NN}}=2.76 TeV. Using NLO QCD, we compute the relative contributions to prompt-photon production from different initial and final states and the theoretical uncertainties coming from independent variations of the renormalisation and factorisation scales, the nuclear parton densities and the fragmentation functions. Based on different fits to the unsubtracted and prompt-photon subtracted ALICE data, we consistently find T = 304 \pm 58 MeV and 309 \pm 64 MeV for the effective temperature of the quark-gluon plasma (or hot medium) at p_T \in [0.8;2.2] GeV and p_T \in [1.5;3.5] GeV as well as a power-law (p_T^{-4}) behavior for p_T > 4 GeV as predicted by QCD hard scattering., Comment: 18 pages, 7 figures, 1 table

Optical solitons or soliton-like states shed light to blue-shifted frequencies through a resonant emission process. We predict a mechanism by which a second propagating mode is generated. This mode, called negative resonant radiation originates from the coupling of the soliton mode to the negative frequency branch of the dispersion relation. Measurements in both bulk media and photonic crystal fibres confirm our predictions.

We observe the dynamics of pulse trapping in a microstructured fiber. Few-cycle pulses create a system of two pulses: a Raman shifting soliton traps a pulse in the normal dispersion regime. When the soliton approaches a wavelength of zero group velocity dispersion the Raman shifting abruptly terminates and the trapped pulse is released. In particular, the trap is less than 4ps long and contains a 1ps pulse. After being released, this pulse asymmetrically expands to more than 10ps. Additionally, there is no disturbance of the trapping dynamics at high input pulse energies as the supercontinuum develops further., Comment: 14 pages, 11 figures

We report on a back-action evading (BAE) measurement of the photon number of fiber optical solitons operating in the quantum regime. We employ a novel detection scheme based on spectral filtering of colliding optical solitons. The measurements of the BAE criteria demonstrate significant quantum state preparation and transfer of the input signal to the signal and probe outputs exiting the apparatus, displaying the quantum-nondemolition (QND) behavior of the experiment., Comment: 5 pages, 5 figures

We report on the generation of a continuous variable Einstein-Podolsky-Rosen (EPR) entanglement using an optical fibre interferometer. The Kerr nonlinearity in the fibre is exploited for the generation of two independent squeezed beams. These interfere at a beam splitter and EPR entanglement is obtained between the output beams. The correlation of the amplitude (phase) quadratures are measured to be 4.0+-0.2 (4.0+-0.4) dB below the quantum noise limit. The sum criterion for these squeezing variances 0.80+-0.03 < 2 verifies the nonseparability of the state. The product of the inferred uncertainties for one beam 0.64+-0.08 is well below the EPR limit of unity., Comment: RevTeX, 4 pages, 3 figures, to be published in Phys. Rev. Lett