cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Probing naked singularities in the charged and uncharged $γ$-metrics with quantum wave packets
Creators: name: Gurtug, Ozay
name: Halilsoy, Mustafa
name: Mangut, Mert
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The non-trivial naked singularities that possess directional behavior in the charged and uncharged Zipoy-Voorhees (ZV) spacetimes, known as γ - metrics are investigated within the context of quantum mechanics. Classically singular spacetime is understood as a geodesic incompleteness with respect to a particle probe, while quantum singularity is understood as a non-unique evolution of test quantum wave packets. In this study, quantum wave packets obeying Klein - Gordon equation are used to probe timelike naked singularities. It is shown by rigorous mathematical calculations that the outermost singularity developed in the charged and uncharged Zipoy-Voorhees spacetime on the equatorial plane is quantum mechanically singular for all values of the deformation parameter γ. However, directional singularities that develop on the symmetry axis is shown to be healed partially for specific range of the parameter γ, if the analysis is restricted purposely to only specific mode (s-wave mode). Allowing arbitrary modes, classical directional singularities remains quantum singular.
description: Slightly detailed version
Language competition in a population of migrating agents
Creators: name: Lipowska, Dorota
name: Lipowski, Adam
Publisher: name: arXiv
Year: 2017
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Influencing various aspects of human activity, migration is associated also with language formation. To examine the mutual interaction of these processes, we study a Naming Game with migrating agents. The dynamics of the model leads to formation of low-mobility clusters, which turns out to break the symmetry of the model: although the Naming Game remains symmetric, low-mobility languages are favoured. High-mobility languages are gradually eliminated from the system and the dynamics of language formation considerably slows down. Our model is too simple to explain in detail language competition of migrating human communities, but it certainly shows that languages of settlers are favoured over nomadic ones.
description: 6 pages, accepted in Phys. Rev. E
Slow light in saturable absorbers : Progress in the resolution of a controversy
Creators: name: Macke, Bruno
name: Razdobreev, Igor
name: Ségard, Bernard
Publisher: name: arXiv
Year: 2017
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: There are two opposing models in the analysis of the slow transmission of light pulses through saturable absorbers. The canonical incoherent bleaching model simply explains the slow transmission by combined effects of saturation and of non-instantaneous response of the medium resulting in absorption of the front part of the incident pulse larger than that of its rear. The second model, referred to as the coherent-population-oscillations (CPO) model, considers light beams whose intensity is slightly pulse modulated and attributes the time delay of the transmitted pulse to a reduction of the group velocity. We point out some inconsistencies in the CPO model and show that the two models lie in reality on the same hypotheses, the equations derived in the duly rectified CPO model being local expressions of the integral equations obtained in the incoherent bleaching model. For large modulation index, the CPO model, based on linearized equations, breaks down. The incoherent bleaching model then predicts that the transmitted light should vanish when the intensity of the incident light is strictly zero. This point is confirmed by the experiments that we have performed on ruby with square-wave incident pulses and we show that the whole shape of the observed pulses agrees with that derived analytically by means of the incoherent bleaching model. We also determine in this model the corresponding evolution of the fluorescence light, which seems to have been evidenced in other experiments.
FRB 121102 Casts New Light on the Photon Mass
Creators: name: Bonetti, Luca
name: Ellis, John
name: Mavromatos, Nikolaos E.
name: Sakharov, Alexander S.
name: Sarkisyan-Grinbaum, Edward K.
name: Spallicci, Alessandro D. A. M.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The photon mass, $m_γ$, can in principle be constrained using measurements of the dispersion measures (DMs) of fast radio bursts (FRBs), once the FRB redshifts are known. The DM of the repeating FRB 121102 is known to $< 1$\%, a host galaxy has now been identified with high confidence,and its redshift, $z$, has now been determined with high accuracy: $z = 0.19273(8)$. Taking into account the plasma contributions to the DM from the Intergalactic medium (IGM) and the Milky Way, we use the data on FRB 121102 to derive the constraint $m_γ\lesssim 2.2 \times 10^{-14}$ eV c$^{-2}$ ($3.9 \times 10^{-50}$ kg). Since the plasma and photon mass contributions to DMs have different redshift dependences, they could in principle be distinguished by measurements of more FRB redshifts, enabling the sensitivity to $m_γ$ to be improved.
description: 9 pages, 1 figure, version to appear in PLB
VESPo: Verified Evaluation of Secret Polynomials
Creators: name: Dumas, Jean-Guillaume
name: Maignan, Aude
name: Pernet, Clément
name: Roche, Daniel S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Cryptography and Security (cs.CR)
subject: Symbolic Computation (cs.SC)
subject: FOS: Computer and information sciences

description: Proofs of Retrievability are protocols which allow a Client to store data remotely and to efficiently ensure, via audits, that the entirety of that data is still intact. Dynamic Proofs of Retrievability (DPoR) also support efficient retrieval and update of any small portion of the data.We propose a novel protocol for arbitrary outsourced data storage that achieves both low remote storage size and audit complexity.A key ingredient, that can be also of intrinsic interest, reduces to efficiently evaluating a secret polynomial at given public points, when the (encrypted) polynomial is stored on an untrusted Server.The Server performs the evaluations and also returns associated certificates. A Client can check that the evaluations are correct using the certificates and some pre-computed keys, more efficiently than re-evaluating the polynomial.Our protocols support two important features: the polynomial itself can be encrypted on the Server, and it can be dynamically updated by changing individual coefficients cheaply without redoing the entire setup.Our methods rely on linearly homomorphic encryption and pairings, and our implementation shows good performance for polynomial evaluations with millions of coefficients, and efficient DPoR with terabytes of data.For instance, for a 1TB database, compared to the state of art, we can reduce the Client storage by 5000x, communication size by 20x, and client-side audit time by 2x, at the cost of one order of magnitude increase in server-side audit time.
Optospintronics in graphene via proximity coupling
Creators: name: Avsar, Ahmet
name: Unuchek, Dmitrii
name: Liu, Jiawei
name: Sanchez, Oriol Lopez
name: Watanabe, Kenji
name: Taniguchi, Takashi
name: Ozyilmaz, Barbaros
name: Kis, Andras
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: The observation of micron size spin relaxation makes graphene a promising material for applications in spintronics requiring long distance spin communication. However, spin dependent scatterings at the contact/graphene interfaces affect the spin injection efficiencies and hence prevent the material from achieving its full potential. While this major issue could be eliminated by nondestructive direct optical spin injection schemes, graphenes intrinsically low spin orbit coupling strength and optical absorption place an obstacle in their realization. We overcome this challenge by creating sharp artificial interfaces between graphene and WSe2 monolayers. Application of a circularly polarized light activates the spin polarized charge carriers in the WSe2 layer due to its spin coupled valley selective absorption. These carriers diffuse into the superjacent graphene layer, transport over a 3.5 um distance, and are finally detected electrically using BN/Co contacts in a non local geometry. Polarization dependent measurements confirm the spin origin of the non local signal.
Unity of pomerons from gauge/string duality
Creators: name: Ballon-Bayona, Alfonso
name: Quevedo, Robert Carcasses
name: Costa, Miguel S.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We develop a formalism where the hard and soft pomeron contributions to high energy scattering arise as leading Regge poles of a single kernel in holographic QCD. The kernel is obtained using effective field theory inspired by Regge theory of a 5-d string theory. It describes the exchange of higher spin fields in the graviton Regge trajectory that are dual to glueball states of twist two. For a specific holographic QCD model we describe Deep Inelastic Scattering in the Regge limit of low Bjorken x, finding good agreement with experimental data from HERA. The observed rise of the effective pomeron intercept, as the size of the probe decreases, is reproduced by considering the first four pomeron trajectories. In the case of soft probes, relevant to total cross sections, the leading hard pomeron trajectory is suppressed, such that in this kinematical region we reproduce an intercept of 1.09 compatible with the QCD soft pomeron data. In the spectral region of positive Maldelstam variable t the first two pomeron trajectories are consistent with current expectations for the glueball spectrum from lattice simulations.
The QCD Equation of State to $\mathcal{O}(μ_B^6)$ from Lattice QCD
Creators: name: Bazavov, A.
name: Ding, H. -T.
name: Hegde, P.
name: Kaczmarek, O.
name: Karsch, F.
name: Laermann, E.
name: Maezawa, Y.
name: Mukherjee, S.
name: Ohno, H.
name: Petreczky, P.
name: Sandmeyer, H.
name: Steinbrecher, P.
name: Schmidt, C.
name: Sharma, S.
name: Soeldner, W.
name: Wagner, M.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We calculated the QCD equation of state using Taylor expansions that include contributions from up to sixth order in the baryon, strangeness and electric charge chemical potentials. Calculations have been performed with the Highly Improved Staggered Quark action in the temperature range $T\in [135~{\rm MeV}, 330~{\rm MeV}]$ using up to four different sets of lattice cut-offs corresponding to lattices of size $N_σ^3\times N_τ$ with aspect ratio $N_σ/N_τ=4$ and $N_τ=6-16$. The strange quark mass is tuned to its physical value and we use two strange to light quark mass ratios $m_s/m_l=20$ and $27$, which in the continuum limit correspond to a pion mass of about $160$ MeV and $140$ MeV espectively. Sixth-order results for Taylor expansion coefficients are used to estimate truncation errors of the fourth-order expansion. We show that truncation errors are small for baryon chemical potentials less then twice the temperature ($μ_B\le 2T$). The fourth-order equation of state thus is suitable for the modeling of dense matter created in heavy ion collisions with center-of-mass energies down to $\sqrt{s_{NN}}\sim 12$ GeV. We provide a parametrization of basic thermodynamic quantities that can be readily used in hydrodynamic simulation codes. The results on up to sixth order expansion coefficients of bulk thermodynamics are used for the calculation of lines of constant pressure, energy and entropy densities in the $T$-$μ_B$ plane and are compared with the crossover line for the QCD chiral transition as well as with experimental results on freeze-out parameters in heavy ion collisions. These coefficients also provide estimates for the location of a possible critical point. We argue that results on sixth order expansion coefficients disfavor the existence of a critical point in the QCD phase diagram for $μ_B/T\le 2$ and $T/T_c(μ_B=0) > 0.9$.
description: Updated to correspond to journal version. The ancillary files, which contain tables of the basic thermodynamic observables calculated for baryon chemical potentials \mu_B/T < 2.2 in the temperature range 135 MeV < T < 280 MeV and for the cases \mu_Q = \mu_S = 0 and n_S=0, n_Q/n_B=0.4, can be found in version v1
The El Gordo galaxy cluster challenges ΛCDM for any plausible collision velocity
Creators: name: Asencio, E.
name: Banik, I.
name: Kroupa, P.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: El Gordo (ACT-CL J0102-4915) is an extraordinarily large and bright galaxy cluster collision. In a previous study, we found that El Gordo is in $6.2σ$ tension with the $Λ$CDM standard model when assuming the nominal mass and infall velocity values from the hydrodynamical simulations of Zhang et al. ($M_{200} = 3.2 \times 10^{15} M_{\odot}$ and $V_{\textrm{infall}} = 2500~\textrm{km~s}^{-1}$, respectively). The recent weak lensing study of Kim et al. showed that the mass of El Gordo is actually $2.13^{+0.25}_{-0.23} \times 10^{15} M_{\odot}$. Here we explore the level of tension between El Gordo and $Λ$CDM for the new mass estimate, assuming several $V_{\textrm{infall}}$ values. We find that in order to reduce the tension below the $5σ$ level, the El Gordo subclusters should have $V_{\textrm{infall}} < 2300~\textrm{km~s}^{-1}$ ($V_{\textrm{infall}} < 1800~\textrm{km~s}^{-1}$ when considering the combined tension with the Bullet Cluster). To the best of our knowledge, the El Gordo hydrodynamical simulations conducted so far require $V_{\textrm{infall}} \geq 2500~\textrm{km~s}^{-1}$ to simultaneously reproduce its morphology and its high X-ray luminosity and temperature. We therefore conclude that El Gordo still poses a significant challenge to $Λ$CDM cosmology. Whether the properties of El Gordo can be reconciled with a lower $V_{\textrm{infall}}$ should be tested with new hydrodynamical simulations that explore different configurations of the interaction.
description: 8 pages, 1 figure. Matched to version published in The Astrophysical Journal as closely as possible
Corrected Weight Functions for Stellar Oscillation Eigenfrequencies
Creators: name: Townsend, R. H. D.
name: Kawaler, S. D.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Kawaler et al. (1985) present a variational expression for the eigenfrequencies associated with stellar oscillations. We highlight and correct a typographical error in the weight functions appearing in these expressions, and validate the correction numerically.
description: 3 pages, 1 figure
Supersymmetric RG flows and Janus from type II orbifold compactification
Creators: name: Karndumri, Parinya
name: Upathambhakul, Khem
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We study holographic RG flow solutions within four-dimensional $N=4$ gauged supergravity obtained from type IIA and IIB string theories compactified on $T^6/\mathbb{Z}_2\times \mathbb{Z}_2$ orbifold with gauge, geometric and non-geometric fluxes. In type IIB non-geometric compactifications, the resulting gauged supergravity has $ISO(3)\times ISO(3)$ gauge group and admits an $N=4$ $AdS_4$ vacuum dual to an $N=4$ superconformal field theory (SCFT) in three dimensions. We study various supersymmetric RG flows from this $N=4$ SCFT to $N=4$ and $N=1$ non-conformal field theories in the IR. The flows preserving $N=4$ supersymmetry are driven by relevant operators of dimensions $Δ=1,2$ or alternatively by one of these relevant operators, dual to the dilaton, and irrelevant operators of dimensions $Δ=4$ while the $N=1$ flows in addition involve marginal deformations. Most of the flows can be obtained analytically. We also give examples of supersymmetric Janus solutions preserving $N=4$ and $N=1$ supersymmetries. These solutions should describe two-dimensional conformal defects within the dual $N=4$ SCFT. Geometric compactifications of type IIA theory give rise to $N=4$ gauged supergravity with $ISO(3)\ltimes U(1)^6$ gauge group. In this case, the resulting gauged supergravity admits an $N=1$ $AdS_4$ vacuum. We also numerically study possible $N=1$ RG flows to non-conformal field theories in this case.
description: 32 pages, 5 figures, typos corrected and references added
GeP3: A small indirect band gap 2D crystal with high carrier mobility and strong interlayer quantum confinement
Creators: name: Jing, Yu
name: Ma, Yandong
name: Li, Yafei
name: Heine, Thomas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We propose a two-dimensional crystal which possesses low indirect band gaps of 0.55 eV (monolayer) and 0.43 eV (bilayer) and high carrier mobilities similar to those of phosphorene: GeP3. GeP3 has a stable three-dimensional layered bulk counterpart which is metallic and is known from experiment since 1970. It has a small cleavage energy, which suggests exfoliation of bulk material as viable means for the preparation of mono- and few-layer materials. The material shows strong interlayer quantum confinement effects, resulting in a band gap reduction from mono- to bilayer, and then to a semiconductor-metal transition between bi- and triple layer. Under biaxial strain, the indirect band gap can be turned into a direct one. Pronounced light absorption in the spectral range from ~600 to 1400 nm is predicted for monolayer and bilayer and promises applications in photovoltaics.
description: 14 pages, 5 figures, submitted
Robust Pre-Grant Signaling for Energy-Efficient 5G and beyond Mobile Devices
Creators: name: Rostami, Soheil
name: Heiska, Kari
name: Puchko, Oleksandr
name: Leppanen, Kari
name: Valkama, Mikko
Publisher: name: Zenodo
Year: 2018

description: Mobile device batteries have severely limited capacities, due to constraints on size and weight of mobile devices. Therefore, energy efficiency of mobile devices plays an important role in their usability. Different power measurement studies show that cellular subsystem of mobile device is one of the major contributors to its energy consumption. Thus, reducing energy consumption of cellular subsystem is paramount. In this paper, a new concept of pre-grant message for control plane is introduced, aiming to reduce energy consumption of cellular subsystem in downlink, while discontinuous reception is activated. Performance of the proposed scheme in terms of false alarm and misdetection are investigated, and evaluated in AWGN and Rayleigh fading channel. The obtained numerical results show that such a signaling can reduce power consumption of mobile device by up to 70% for bursty data applications, at the cost of negligible increments in signaling overhead.
Origin of the East Sulawesi Ophiolite, Eastern Indonesia: implications for oceanic crust generation and tectonic reconstruction in the Western Pacific
Creators: name: Liao, Chia-Ping
Publisher: name: Monash University
Year: 2024
Subjects: classificationCode: 370303
subject: Isotope geochemistry
classificationCode: 370503
subject: Igneous and metamorphic petrology
classificationCode: 370302
subject: Inorganic geochemistry

description: The PhD thesis explores the origin of the East Sulawesi Ophiolite in Sulawesi, Indonesia. Ophiolites, rock remnants of oceanic lithosphere thrust onto land, offers insights into past tectonic events. I measured chemical and isotope compositions of rocks and minerals, suggesting that the magma originated from a mantle source modified by subduction. Zircon U-Pb dating reveals the existence of ancient exotic continental zircons in young oceanic rocks, sourced from subducted sediments from the Australian continental margin, indicating its past location close to the margin. Apatite chemical compositions record the effect of pre-existing zircons and the dynamic zircon-apatite competition process during crystallization.
Gravity as a Quantum Effect on Quantum Space-Time
Creators: name: Steinacker, Harold C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The 3+1-dimensional Einstein-Hilbert action is obtained from the 1-loop effective action on noncommutative branes in the IIB or IKKT matrix model. The presence of compact fuzzy extra dimensions ${\cal K}$ as well as maximal supersymmetry of the model is essential. The E-H action can be interpreted as interaction of ${\cal K}$ with the space-time brane via IIB supergravity, and the effective Newton constant is determined by the Kaluza-Klein scale of ${\cal K}$. The bare matrix model defines a pre-gravity action with 2 derivatives less than the induced E-H action, governing the cosmological regime. The perturbative physics is confined to the space-time brane, which for covariant quantum space-times includes all dof of gravity, as well as a tower of higher-spin modes. The vacuum energy is given in terms of the symplectic volume form, and hence does not act as cosmological constant.
description: 6 pages. V2: dilaton contribution corrected, references added, published version. V3: action corrected, conclusion unchanged
Gravito-turbulence in irradiated protoplanetary discs
Creators: name: Hirose, Shigenobu
name: Shi, Ji-Ming
Publisher: name: arXiv
Year: 2017
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Using radiation hydrodynamics simulations in a local stratified shearing box with realistic equations of state and opacities, we explored the outcome of self-gravity at 50 AU in a protoplanetary disc irradiated by the central star. We found that gravito-turbulence is sustained for a finite range of the surface density, from $\sim 80$ to $\sim$ 250 gcm$^{-2}$. The disk is laminar below the range while fragments above it. In the range of gravito-turbulence, the Toomre parameter decreases monotonically from $\sim 1$ to $\sim 0.7$ as the surface density increases while an effective cooling time is almost constant at $\sim 4$ in terms of the inverse of the orbital frequency. The turbulent motions are supersonic at all heights, which dissipates through both shock waves and compressional heating. The compressional motions, occurring near the midplane, create upward flows, which not only contribute to supporting the disc but also to transporting the dissipated energy to the disc surfaces. The irradiation does not affect much the gravito-turbulence near the midplane unless the grazing angle is larger than 0.32. We also show that a simple cooling function with a constant cooling time does not approximate the realistic cooling.
description: accepted for publication in MNRAS
Superionic phase transition of copper(I) sulfide and its implication for purported superconductivity of LK-99
Creators: name: Jain, Prashant K.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Lee, Kim, and coworkers have recently claimed room-temperature and ambient-pressure superconductivity in a copper-doped lead apatite material named LK-99. However, the polycrystalline material synthesized has a significant fraction of copper(I) sulfide. Copper(I) sulfide has a known phase transition at 104 degrees C from an ordered low-temperature phase to a high-temperature superionic phase. As a result of this phase transition, copper(I) sulfide exhibits sharp transitions in electrical resistivity and heat capacity, which are expected to coincide with the temperature-induced transitions reported for LK-99. This implies that LK-99 must be synthesized without any copper(I) sulfide to allow unambiguous validation of the superconducting properties of LK-99.
description: 6 pages, 3 figures
Origin of warm and hot gas emission from low-mass protostars: Herschel-HIFI observations of CO J=16-15. I. Line profiles, physical conditions, and H2O abundance
Creators: name: Kristensen, L. E.
name: van Dishoeck, E. F.
name: Mottram, J. C.
name: Karska, A.
name: Yildiz, U. A.
name: Bergin, E. A.
name: Bjerkeli, P.
name: Cabrit, S.
name: Doty, S.
name: Evans, N. J.
name: Gusdorf, A.
name: Harsono, D.
name: Herczeg, G. J.
name: Johnstone, D.
name: Jørgensen, J. K.
name: van Kempen, T. A.
name: Lee, J. -E.
name: Maret, S.
name: Tafalla, M.
name: Visser, R.
name: Wampfler, S. F.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: (Abridged) Through spectrally unresolved observations of high-J CO transitions, Herschel-PACS has revealed large reservoirs of warm (300 K) and hot (700 K) molecular gas around low-mass protostars. We aim to shed light on the excitation and origin of the CO ladder observed toward protostars, and on the water abundance in different physical components using spectrally resolved Herschel-HIFI data. Observations are presented of the highly excited CO line J=16-15 with Herschel-HIFI toward 24 low-mass protostellar objects. The spectrally resolved profiles show two distinct velocity components: a broad component with an average FWHM of 20 km/s, and a narrower component with a FWHM of 5 km/s that is often offset from the source velocity. The average rotational temperature over the entire profile, as measured from comparison between CO J=16-15 and 10-9 emission, is ~300 K. A radiative-transfer analysis shows that the average H2O/CO column-density ratio is ~0.02, suggesting a total H2O abundance of ~2x10^-6. Two distinct velocity profiles observed in the HIFI line profiles suggest that the CO ladder observed with PACS consists of two excitation components. The warm component (300 K) is associated with the broad HIFI component, and the hot component (700 K) is associated with the offset HIFI component. The former originates in either outflow cavity shocks or the disk wind, and the latter in irradiated shocks. The ubiquity of the warm and hot CO components suggests that fundamental mechanisms govern the excitation of these components; we hypothesize that the warm component arises when H2 stops being the dominant coolant. In this scenario, the hot component arises in cooling molecular H2-poor gas just prior to the onset of H2 formation. High spectral resolution observations of highly excited CO transitions uniquely shed light on the origin of warm and hot gas in low-mass protostellar objects.
description: Accepted for publication in A&A
Extended depth-range profilometry using the phase-difference and phase-sum of two close-sensitivity projected fringes
Creators: name: Servin, Manuel
name: Padilla, Moises
name: Garnica, Guillermo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We propose a high signal-to-noise extended depth-range three-dimensional (3D) profilometer projecting two linear-fringes with close phase-sensitivity. We use temporal phase-shifting algorithms (PSAs) to phase-demodulate the two close sensitivity phases. Then we calculate their phase-difference and their phase-sum. If the sensitivity between the two phases is close enough, their phase-difference is not-wrapped. The non-wrapped phase-difference as extended-range profilometry is well known and has been widely used. However as this paper shows, the closeness between the two demodulated phases makes their difference quite noisy. On the other hand, as we show, their phase-sum has a much higher phase-sensitivity and signal-to-noise ratio but it is highly wrapped. Spatial unwrapping of the phase-sum is precluded for separate or highly discontinuous objects. However it is possible to unwrap the phase-sum by using the phase-difference as first approximation and our previously published 2-step temporal phase-unwrapping. Therefore the proposed profilometry technique allows unwrapping the higher sensitivity phase-sum using the noisier phase-difference as stepping stone. Due to the non-linear nature of the extended 2-steps temporal-unwrapper, the harmonics and noise errors in the phase-difference do not propagate towards the unwrapping phase-sum. To the best of our knowledge this is the highest signal-to-noise ratio, extended depth-range, 3D digital profilometry technique reported to this date.
description: This arXiv article arXiv:1704.04662 was withdraw because it was replaced by the arXiv article arXiv:1706.04039
Constraints on the trilinear Higgs self coupling from precision observables
Creators: name: Degrassi, Giuseppe
name: Fedele, Marco
name: Giardino, Pier Paolo
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We present the constraints on the trilinear Higgs self coupling that arise from loop effects in the $W$ boson mass and the effective sine predictions. We compute the contributions to these precision observables of two-loop diagrams featuring an anomalous trilinear Higgs self coupling. We explicitly show that the same anomalous contributions are found if the analysis of $m_{ \scriptscriptstyle W}$ and $\mbox{$\sin^2 θ^{\rm lep}_{\rm eff}$}$ is performed in a theory in which the scalar potential in the Standard Model Lagrangian is modified by an (in)finite tower of $(Φ^\dagger Φ)^n$ terms with $Φ$ the Higgs doublet. We find that the bounds on the trilinear Higgs self coupling from precision observables are competitive with those coming from Higgs pair production.
description: 23 pages, 4 figures; V2: References added, version published on JHEP
Why and whence the Hilbert space in quantum theory?
Creators: name: Brezhnev, Yu. V.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We explain why and how the Hilbert space comes about in quantum theory. The axiomatic structures of vector space, of scalar product, of orthogonality, and of the linear functional are derivable from the statistical description of quantum micro-events and from Hilbertian sum of squares $|\mathfrak{a}_1|^2+|\mathfrak{a}_2|^2+\cdots$. The latter leads (non-axiomatically) to the standard writing of the Born formula $\mathtt{f} = |\langleψ|φ\rangle|^2$. As a corollary, the status of Pythagorean theorem, the concept of a length, and the 6-th Hilbert problem undergo a quantum `revision'. An issue of deriving the norm topology may no have a short-length solution (too many abstract math-axioms) but is likely solvable in the affirmative; the problem is reformulated as a mathematical one.
description: 28 pages; no figures; final version (slightly extended version of the journal one)
Numerical simulations and infrared spectro-interferometry reveal the wind collision region in gamma2 Velorum
Creators: name: Lamberts, A.
name: Millour, F.
name: Liermann, A.
name: Dessart, L.
name: Driebe, T.
name: Duvert, G.
name: Finsterle, W.
name: Girault, V.
name: Massi, F.
name: Petrov, R. G.
name: Schmutz, W.
name: Weigelt, G.
name: Chesneau, O.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Colliding stellar winds in massive binary systems have been studied through their radio, optical lines and strong X-ray emission for decades. More recently, near-infrared spectrointerferometric observations have become available in a few systems, but isolating the contribution from the individual stars and the wind collision region still remains a challenge. In this paper, we study the colliding wind binary gamma2 Velorum and aim at identifying the wind collision zone from infrared interferometric data, which provide unique spatial information to determine the wind properties. Our analysis is based on multi-epoch VLTI/AMBER data that allows us to separate the spectral components of both stars. First, we determine the astrometric solution of the binary and confirm previous distance measurements. We then analyse the spectra of the individual stars, showing that the O star spectrum is peculiar within its class. Then, we perform three-dimensional hydrodynamic simulations of the system from which we extract model images, visibility curves and closure phases which can be directly compared with the observed data. The hydrodynamic simulations reveal the 3D spiral structure of the wind collision region, which results in phase-dependent emission maps. Our model visibility curves and closure phases provide a good match when the wind collision region accounts for 3 to 10 per cent of the total flux in the near infrared. The dialogue between hydrodynamic simulations, radiative transfer models and observations allows us to fully exploit the observations. Similar efforts will be crucial to study circumstellar environments with the new generation of VLTI instruments like GRAVITY and MATISSE.
description: 17 pages, 14 figures, accepted to MNRAS March, 7, 2017
Wireless Powered Wake-up Receiver for Ultra-Low-Power Devices
Creators: name: Rostami, Soheil
name: Heiska, Kari
name: Puchko, Oleksandr
name: Leppanen, Kari
name: Valkama, Mikko
Publisher: name: Zenodo
Year: 2018

description: Energy-constrained wireless networks and devices are mainly powered by batteries, which have severely limited capacities, demanding to be regularly recharged or replaced. Thus energy conservation plays a pivotal role in the operational lifetime of such networks. In this paper, the concept of a wireless powered wake-up receiver is studied, aiming to reduce energy consumption of the wireless node. The proposed wireless powered wake-up receiver scheme can be utilized for a range of energy-constrained wireless applications such as wireless sensor actuator networks, machine-to-machine communications, and the Internet-of-Things. Preliminary numerical results show that such a scheme can reduce energy consumption of wireless nodes considerably, at the cost of an extra low-power low-cost wake-up receiver.
Interplay between particle trapping and heterogeneity in anomalous diffusion
Creators: name: Ribeiro, Haroldo V.
name: Tateishi, Angel A.
name: Lenzi, Ervin K.
name: Magin, Richard L.
name: Perc, Matjaz
Publisher: name: arXiv
Year: 2023
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: Heterogeneous media diffusion is often described using position-dependent diffusion coefficients and estimated indirectly through mean squared displacement in experiments. This approach may overlook other mechanisms and their interaction with position-dependent diffusion, potentially leading to erroneous conclusions. Here, we introduce a hybrid diffusion model that merges a position-dependent diffusion coefficient with the trapping mechanism of the comb model. We derive exact solutions for position distributions and mean squared displacements, validated through simulations of Langevin equations. Our model shows that the trapping mechanism attenuates the impact of media heterogeneity. Superdiffusion occurs when the position-dependent coefficient increases superlinearly, while subdiffusion occurs for sublinear and inverse power-law relations. This nontrivial interplay between heterogeneity and state-independent mechanisms also leads to anomalous yet Brownian and non-Brownian yet Gaussian regimes. These findings emphasize the need for cautious interpretations of experiments and highlight the limitations of relying solely on mean squared displacements or position distributions for diffusion characterization.
description: 13 two-column pages, 6 figures; accepted for publication in Communications Physics
USDA’s New Interactive Visualization Tool Aids Exploration of Global Agricultural Trends
Creators: name: Gerval, Adam
name: Gerval, Adam
Publisher: name: Unknown
Year: 2022
Subjects: subject: International Development
subject: Labor and Human Capital
subject: Land Economics/Use
subject: Marketing
subject: FOS: Economics and business
subject: Political Economy
subject: Production Economics
subject: Productivity Analysis
subject: Research and Development/Tech Change/Emerging Technologies
subject: Research Methods/ Statistical Methods
subject: Resource /Energy Economics and Policy
subject: Risk and Uncertainty
subject: Teaching/Communication/Extension/Profession

description: USDA, Economic Research Service (ERS) has developed a new tool to help explore trends in global agriculture from an array of international data. The tool, the International Baseline Visualization, is available on the ERS website. It provides users with access to data for 44 exporting and importing countries and regions in conjunction with USDA’s agricultural commodity and macroeconomic models. The tool includes data for aggregated regional models for which USDA regularly reports, such as “Other Europe” and “Other South America.” The tool not only contains international data, but it also houses domestic data for the United States. Historical and projected data for production, consumption, and trade are available through a custom data query function that allows users to download data by commodity, continent, and region or country. The visualization will be updated annually in tandem with the USDA’s 10-year international agricultural projections.
U.S. Agricultural Trade Showed Resiliency Through COVID-19 Pandemic
Creators: name: Gerval, Adam
name: Gerval, Adam
Publisher: name: Unknown
Year: 2022
Subjects: Agribusiness
Crop Production/Industries
Demand and Price Analysis
Farm Management
Financial Economics
Production Economics
Productivity Analysis

description: The overall value of U.S. agricultural trade increased in 2020 and 2021, despite global economic downturns from the Coronavirus (COVID-19) pandemic. In 2020, the United States exported $149.7 billion in agricultural exports, 6.1 percent more than the previous year and a 5-year high. The next year (2021), the value of U.S. agricultural exports rose an additional 18.9 percent to $177.0 billion. Soybean exports to China accounted for much of the increase in 2020, concentrated in the final 3 months of 2020 and offsetting declines in the value of many other U.S. agricultural exports in the early months of the pandemic.
Multiple antiferromagnetic phases and magnetic anisotropy in exfoliated CrBr$_3$ multilayers
Creators: name: Yao, Fengrui
name: Multian, Volodymyr
name: Wang, Zhe
name: Ubrig, Nicolas
name: Teyssier, Jérémie
name: Wu, Fan
name: Giannini, Enrico
name: Gibertini, Marco
name: Gutiérrez-Lezama, Ignacio
name: Morpurgo, Alberto F.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: In twisted two-dimensional (2D) magnets, the stacking dependence of the magnetic exchange interaction can lead to regions of ferromagnetic and antiferromagnetic interlayer order, separated by non-collinear, skyrmion-like spin textures. Recent experimental searches for these textures have focused on CrI$_3$, known to exhibit either ferromagnetic or antiferromagnetic interlayer order, depending on layer stacking. However, the very strong uniaxial anisotropy of CrI$_3$ disfavors smooth non-collinear phases in twisted bilayers. Here, we report the experimental observation of three distinct magnetic phases -- one ferromagnetic and two antiferromagnetic -- in exfoliated CrBr$_3$ multilayers, and reveal that the uniaxial anisotropy is significantly smaller than in CrI$_3$. These results are obtained by magnetoconductance measurements on CrBr$_3$ tunnel barriers and Raman spectroscopy, in conjunction with density functional theory calculations, which enable us to identify the stackings responsible for the different interlayer magnetic couplings. The detection of all locally stable magnetic states predicted to exist in CrBr$_3$ and the excellent agreement found between theory and experiments, provide complete information on the stacking-dependent interlayer exchange energy and establish twisted bilayer CrBr$_3$ as an ideal system to deterministically create non-collinear magnetic phases.
Application and performance of an ML-EM algorithm in NEXT
Creators: name: NEXT Collaboration
name: Simón, A.
name: Lerche, C.
name: Monrabal, F.
name: Gómez-Cadenas, J. J.
name: Álvarez, V.
name: Azevedo, C. D. R.
name: Benlloch-Rodríguez, J. M.
name: Borges, F. I. G. M.
name: Botas, A.
name: Cárcel, S.
name: Carrión, J. V.
name: Cebrián, S.
name: Conde, C. A. N.
name: Díaz, J.
name: Diesburg, M.
name: Escada, J.
name: Esteve, R.
name: Felkai, R.
name: Fernandes, L. M. P.
name: Ferrario, P.
name: Ferreira, A. L.
name: Freitas, E. D. C.
name: Goldschmidt, A.
name: González-Díaz, D.
name: Gutiérrez, R. M.
name: Hauptman, J.
name: Henriques, C. A. O.
name: Hernandez, A. I.
name: Morata, J. A. Hernando
name: Herrero, V.
name: Jones, B. J. P.
name: Labarga, L.
name: Laing, A.
name: Lebrun, P.
name: Liubarsky, I.
name: López-March, N.
name: Losada, M.
name: Martín-Albo, J.
name: Martínez-Lema, G.
name: Martínez, A.
name: McDonald, A. D.
name: Monteiro, C. M. B.
name: Mora, F. J.
name: Moutinho, L. M.
name: Vidal, J. Muñoz
name: Musti, M.
name: Nebot-Guinot, M.
name: Novella, P.
name: Nygren, D. R.
name: Palmeiro, B.
name: Para, A.
name: Pérez, J.
name: Querol, M.
name: Renner, J.
name: Ripoll, L.
name: Rodríguez, J.
name: Rogers, L.
name: Santos, F. P.
name: Santos, J. M. F. dos
name: Sofka, C.
name: Sorel, M.
name: Stiegler, T.
name: Toledo, J. F.
name: Torrent, J.
name: Tsamalaidze, Z.
name: Veloso, J. F. C. A.
name: Webb, R.
name: White, J. T.
name: Yahlali, N.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The goal of the NEXT experiment is the observation of neutrinoless double beta decay in $^{136}$Xe using a gaseous xenon TPC with electroluminescent amplification and specialized photodetector arrays for calorimetry and tracking. The NEXT Collaboration is exploring a number of reconstruction algorithms to exploit the full potential of the detector. This paper describes one of them: the Maximum Likelihood Expectation Maximization (ML-EM) method, a generic iterative algorithm to find maximum-likelihood estimates of parameters that has been applied to solve many different types of complex inverse problems. In particular, we discuss a bi-dimensional version of the method in which the photosensor signals integrated over time are used to reconstruct a transverse projection of the event. First results show that, when applied to detector simulation data, the algorithm achieves nearly optimal energy resolution (better than 0.5% FWHM at the Q value of $^{136}$Xe) for events distributed over the full active volume of the TPC.
description: 19 pages, 16 figures
Application of some techniques in Sperner Theory: Optimal orientations of vertex-multiplications of trees with diameter 4
Creators: name: Wong, W. H. W.
name: Tay, E. G.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: G.2.2; F.2.2
subject: 05C12, 05C20, 05D05

description: Koh and Tay proved a fundamental classification of $G$ vertex-multiplications into three classes $\mathscr{C}_0, \mathscr{C}_1$ and $\mathscr{C}_2$. They also showed that any vertex-multiplication of a tree with diameter at least 3 does not belong to the class $\mathscr{C}_2$. Of interest, $G$ vertex-multiplications are extensions of complete $n$-partite graphs and Gutin characterised complete bipartite graphs with an ingenious use of Sperner's Theorem. In this paper, we investigate vertex-multiplications of trees with diameter $4$ in $\mathscr{C}_0$ (or $\mathscr{C}_1$) and exhibit its intricate connections with problems in Sperner Theory, thereby extending Gutin's approach. Let $s$ denote the vertex-multiplication of the central vertex. We almost completely characterise the case of even $s$ and give a complete characterisation for the case of odd $s\ge 3$.
description: 78 pages
Reproduction d’une gravure sur cuivre intitulée « Hermitage de Notre-Dame de la Consolation près de Collioure », face page 160 de l’ouvrage de Melling « Voyage pittoresque dans les Pyrénées françaises » (1826-1830), appartenant à Henri Ribeil. Vue détaillée du quart inférieur gauche
Creators: name: Musée National Des Arts Et Traditions Populaires (Paris)
name: Centre D'ethnologie Française
Publisher: name: École des Hautes Études en Sciences Sociales; Institut  interdisciplinaire d'anthropologie du contemporain (Paris); Laboratoire d'anthropologie et d'histoire de l'institution de la culture (Paris)
Year: 2022

Abstract
Wireless Backhauling for Energy Harvesting Ultra-Dense Networks
Creators: name: Rostami, Soheil
name: Heiska, Kari
name: Puchko, Oleksandr
name: Koudouridis, George P.
name: Leppanen, Kari
name: Valkama, Mikko
Publisher: name: Zenodo
Year: 2018

description: Due to a non-negligible amount of energy consumption of state-of-the-art small cells at idle mode, energy efficiency of network decreases with densification. Therefore, energy efficiency in ultra-dense networks (UDNs) is one of the key challenges for mobile network operators (MNOs) to reduce their operative expenditure (OPEX), and to mitigate the carbon footprint. Low-power and low-cost dense networks are vital to extend next generation cellular networks functionalities by improving network capacity in hot-spot areas, and to deploy networks in short time periods. In energy harvesting networks, access points (APs) may perform both backhaul and access data communication, simultaneously; removing UDN dependency on optical distribution network and electrical grid. In this paper, different power modes and essential signaling for operation of such Aps are introduced, aiming to reduce energy consumption of UDNs by integrating energy harvesters into APs, equipped with wireless backhaul