cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Electron Preacceleration at Weak Quasi-perpendicular Intracluster Shocks: Effects of Preexisting Nonthermal Electrons
Creators: name: Ha, Ji-Hoon
name: Ryu, Dongsu
name: Kang, Hyesung
name: Kim, Sunjung
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Radio relics in the outskirts of galaxy clusters imply the diffusive shock acceleration (DSA) of electrons at merger-driven shocks with Mach number $M_{s}\lesssim3-4$ in the intracluster medium (ICM). Recent studies have suggested that electron preacceleration and injection, prerequisite steps for DSA, could occur at supercritical shocks with $M_{s}\gtrsim2.3$ in the ICM, thanks to the generation of multiscale waves by microinstabilities such as the Alfvén ion cyclotron (AIC) instability, the electron firehose instability (EFI), and the whistler instability (WI). On the other hand, some relics are observed to have subcritical shocks with $M_{s}\lesssim2.3$, leaving DSA at such weak shocks as an outstanding problem. Reacceleration of preexisting nonthermal electrons has been contemplated as one of possible solutions for that puzzle. To explore this idea, we perform Particle-in-Cell (PIC) simulations for weak quasi-perpendicular shocks in high-$β$ ($β=P_{\rm gas}/P_{B}$) plasmas with power-law suprathermal electrons in addition to Maxwellian thermal electrons. We find that suprathermal electrons enhance the excitation of electron-scale waves via the EFI and WI. However, they do not affect the ion reflection and the ensuing generation of ion-scale waves via the AIC instability. The presence of ion-scale waves is the key for the preacceleration of electrons up to the injection momentum, thus the shock criticality condition for electron injection to DSA is preserved. Based on the results, we conclude that preexisting nonthermal electrons in the preshock region alone would not resolve the issue of electron preacceleration at subcritical ICM shocks.
description: 12 pages, 7 figures, to appear in ApJ
Quantifying and containing the curse of high resolution coronal imaging
Creators: name: Delouille, Véronique
name: Chainais, Pierre
name: Hochedez, Jean-François
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Future missions such as Solar Orbiter (SO), InterHelioprobe, or Solar Probe aim at approaching the Sun closer than ever before, with on board some high resolution imagers (HRI) having a subsecond cadence and a pixel area of about $(80km)^2$ at the Sun during perihelion. In order to guarantee their scientific success, it is necessary to evaluate if the photon counts available at these resolution and cadence will provide a sufficient signal-to-noise ratio (SNR). We perform a first step in this direction by analyzing and characterizing the spatial intermittency of Quiet Sun images thanks to a multifractal analysis. We identify the parameters that specify the scale-invariance behavior. This identification allows next to select a family of multifractal processes, namely the Compound Poisson Cascades, that can synthesize artificial images having some of the scale-invariance properties observed on the recorded images. The prevalence of self-similarity in Quiet Sun coronal images makes it relevant to study the ratio between the SNR present at SoHO/EIT images and in coarsened images. SoHO/EIT images thus play the role of 'high resolution' images, whereas the 'low-resolution' coarsened images are rebinned so as to simulate a smaller angular resolution and/or a larger distance to the Sun. For a fixed difference in angular resolution and in Spacecraft-Sun distance, we determine the proportion of pixels having a SNR preserved at high resolution given a particular increase in effective area. If scale-invariance continues to prevail at smaller scales, the conclusion reached with SoHO/EIT images can be transposed to the situation where the resolution is increased from SoHO/EIT to SO/HRI resolution at perihelion.
description: 25 pages, 1 table, 7 figures
A sufficient condition for a number to be the order of a nonsingular derivation of a Lie algebra
Creators: name: Mattarei, Sandro
Publisher: name: arXiv
Year: 2007
Subjects: subject: Rings and Algebras (math.RA)
subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 17B50, 17B40, 12C15, 20C15

description: A study of the set N_p of positive integers which occur as orders of nonsingular derivations of finite-dimensional non-nilpotent Lie algebras of characteristic p>0 was initiated by Shalev and continued by the present author. The main goal of this paper is to show the abundance of elements of N_p. Our main result shows that any divisor n of q-1, where q is a power of p, such that $n\ge (p-1)^{1/p} (q-1)^{1-1/(2p)}$, belongs to N_p. This extends its special case for p=2 which was proved in a previous paper by a different method.
description: 10 pages. This version has been revised according to a referee's suggestions. The additions include a discussion of the (lower) density of the set N_p, and the results of more extensive machine computations. Note that the title has also changed. To appear in Israel J. Math
Dardanus lagopodes
Creators: name: Celia, Maria
name: Malay, D.
name: Miller, Allison K.
name: Komai, Tomoyuki
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Diogenidae
Dardanus
Dardanus lagopodes

description: Dardanus lagopodes (Forskål 1775)
Fig. 4b
Material. 1 specimen (UF 5797), Anatahan Island, station ANA-005; 1 specimen (UF 7396), Guguan Island, station GUG-001; 1 specimen (UF 5800), Guguan Island, station GUG-002; 1 specimen (UF 7820), Guguan Island, GUG-002; 1 specimen (UF 5806), Pagan Island, station PAG-01; 1 juvenile (SIO-BIC C14505), Pagan Island, station AKM-PAG-00P3; 2 specimens (UF 7445), Agrihan Island, station AGR-03; 1 specimen (SIO-BIC C14506), Agrihan Island, station AKM-AGR-00A3; 1 specimen (UF 7441) Asuncion Island, station ASU-02; 1 specimen (UF 5796), Asuncion Island, station ASU-02; 2 specimens (UF 5803), Maug Islands, station MAUG-02.
Remarks. For a long time, D. lagopodes was confused with D. sanguinolentus. See remarks under D. sanguinolentus.
description: Published as part of Celia, Maria, Malay, D., Miller, Allison K. & Komai, Tomoyuki, 2021, Hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) of the Northern Marianas, including new records and an updated checklist, pp. 1-29 in Micronesica 2021 (1) on page 11, DOI: 10.5281/zenodo.12118323
Quantum phase slips in a confined geometry
Creators: name: Khlebnikov, S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We consider tunneling of vortices across a superconducting film that is both narrow and short (and connected to bulk superconducting leads at the ends). We find that in the superconducting state the resistance, at low values of the temperature (T) and current, does not follow the power-law dependence on T characteristic of longer samples but is exponential in 1/T. The coefficient of 1/T in the exponent depends on the length or, equivalently, the total normal-state resistance of the sample. These conclusions persist in the one-dimensional limit, which is similar to the problem of quantum phase slips in an ultra-narrow short wire.
description: 14 pages, 1 figure; published in Phys. Rev. B
Pseudopaguristes undetermined
Creators: name: Celia, Maria
name: Malay, D.
name: Miller, Allison K.
name: Komai, Tomoyuki
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Diogenidae
Pseudopaguristes
Pseudopaguristes undetermined

description: Pseudopaguristes sp.
Material. 1 male, SL 2.5 mm (SIO-BIC C14508), Sarigan Island, station AKM-SAR-03.
Remarks. The sole male specimen appears to represent an undescribed species of Pseudopaguristes, similar to P. bollandi Asakura & Mclaughlin 2003 or P. janetkae McLaughlin 2002, but exhibiting different coloration. This undescribed species will be dealt with in a separate paper (Komai et al., in preparation).
description: Published as part of Celia, Maria, Malay, D., Miller, Allison K. & Komai, Tomoyuki, 2021, Hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) of the Northern Marianas, including new records and an updated checklist, pp. 1-29 in Micronesica 2021 (1) on page 13, DOI: 10.5281/zenodo.12118323
Effects of crowding and water borne stressors on five fishes with different social and ecological habits
Creators: name: Furnell, Donald J.
Publisher: name: University of British Columbia
Year: 2010

description: The responses of five ethologically distinct fishes to crowding and water born stressors were examined. Initial experiments using one stocking density indicated activated carbon removed a water born stressor inhibiting growth in Corynopoma riisei but not Rivulus harti. Later experiments using Brachydanio rerio, Astronotus ocellatus, and Betta splendens confirmed the removal of a water born stressor by activated carbon for all but Betta splendens. The stressor's effect appeared to depend on a species' natural habitat. When cultured, fishes adapted to small transient water bodies tolerated or did not secrete stressors; those from permanent, rapidly diluting environments were inhibited in growth or survival. Response to crowding or social interaction was examined in Brachydanio rerio, Astronotus ocellatus and Betta splendens. Reduction of growth or survival was directly related to stocking density in Brachydanio rerio and Astronotus ocellatus, but the effect was less than half that of water born stressors. In Astronotus ocellatus crowding stress reached a threshold beyond which increased density had no effect. Social interaction in Betta splendens did not inhibit growth, but caused an increase in energy consumption. No relationship between a species' social habits and response to crowding could be discerned. In Brachydanio rerio and Astronotus ocellatus, the combined effects were compensatory or additive, respectively, when crowding and water born stressors were simultaneously examined.
Time and trigger distribution for NUSTAR DAQ systems
Creators: name: Charpy, A.
name: Frühauf, J.
name: Heinz, A.
name: Hoffmann, J.
name: Johansson, H. T.
name: Koch, K.
name: Kurz, N.
name: Pietri, S.
name: Simon, H.
Publisher: name: GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt
Year: 2014
Subjects: Physics

description: GSI Scientific Report 2013 - GSI Report 2014-1
On the Impact of Inclination-Dependent Attenuation on Derived Star Formation Histories: Results from Disk Galaxies in the Great Observatories Origins Deep Survey Fields
Creators: name: Doore, Keith
name: Eufrasio, Rafael T.
name: Lehmer, Bret D.
name: Monson, Erik B.
name: Basu-Zych, Antara
name: Garofali, Kristen
name: Ptak, Andrew
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We develop and implement an inclination-dependent attenuation prescription for spectral energy distribution (SED) fitting and study its impact on derived star-formation histories. We apply our prescription within the SED fitting code Lightning to a clean sample of 82, z=0.21-1.35 disk-dominated galaxies in the Great Observatories Origins Deep Survey North and South fields. To compare our inclination-dependent attenuation prescription with more traditional fitting prescriptions, we also fit the SEDs with the inclination-independent Calzetti et al. (2000) attenuation curve. From this comparison, we find that fits to a subset of 58, z < 0.7 galaxies in our sample, utilizing the Calzetti et al. (2000) prescription, recover similar trends with inclination as the inclination-dependent fits for the far-UV-band attenuation and recent star-formation rates. However, we find a difference between prescriptions in the optical attenuation (AV) that is strongly correlated with inclination (p-value < 10^-11). For more face-on galaxies, with i < 50 deg, (edge-on, i = 90 deg), the average derived AV is 0.31 +\- 0.11 magnitudes lower (0.56 +\- 0.16 magnitudes higher) for the inclination-dependent model compared to traditional methods. Further, the ratio of stellar masses between prescriptions also has a significant (p-value < 10^-2) trend with inclination. For i = 0-65 deg, stellar masses are systematically consistent between fits, with log(Mstar_inc/Mstar_Calzetti) = -0.05 +/- 0.03 dex and scatter of 0.11 dex. However, for i = 80-90 deg, derived stellar masses are lower for the Calzetti et al. (2000) fits by an average factor of 0.17 +\- 0.03 dex and scatter of 0.13 dex. Therefore, these results suggest that SED fitting assuming the Calzetti et al. (2000) attenuation law potentially underestimates stellar masses in highly inclined disk-dominated galaxies.
description: 38 pages, 22 figures. 30 page body and 8 page appendix. Updated with published version
Neutron stars within the SU(2) parity doublet model
Creators: name: Dexheimer, V.
name: Pagliara, G.
name: Tolos, L.
name: Schaffner-Bielich, J.
name: Schramm, S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The equation of state of beta-stable and charge neutral nucleonic matter is computed within the SU(2) parity doublet model in mean field and in the relativistic Hartree approximation. The mass of the chiral partner of the nucleon is assumed to be 1200 MeV. The transition to the chiral restored phase turns out to be a smooth crossover in all the cases considered, taking place at a baryon density of just $2ρ_0$. The mass-radius relations of compact stars are calculated to constrain the model parameters from the maximum mass limit of neutron stars. It is demonstrated that chiral symmetry starts to be restored, which in this model implies the appearance of the chiral partners of the nucleons, in the center of neutron stars. However, the analysis of the decay width of the assumed chiral partner of the nucleon poses limits on the validity of the present version of the model to describe vacuum properties.
description: 14 pages, 9 figures, 2 tables, version accepted for publication in EJPA
Comparison with experimental data of different theoretical approaches to high-energy electron bremsstrahlung including quantum coherence effects
Creators: name: Mangiarotti, A.
name: Sona, P.
name: Uggerhøj, U. I.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The basic expressions for the differential nuclear bremsstrahlung cross section at high electron energy, as derived under different theoretical approaches and approximations to quantum coherence effects, are compared. The Baier-Katkov treatment is reformulated to allow introduction of the same value of the radiation length in all calculations. A dedicated Monte Carlo code is employed for obtaining photon energy spectra in the framework of the Baier-Katkov approach taking into account multiphoton emission, attenuation by pair production, and pile-up with photons from the background. The results of Monte Carlo simulations for both the Migdal and Baier-Katkov descriptions are compared to all available data that show the Landau-Pomeranchuk-Migdal suppression. The issue of the sensitivity of the experiments to the difference of the two approaches is investigated.
description: 32 pages, 25 figures, full paper
Context-aware Adversarial Training for Name Regularity Bias in Named Entity Recognition
Creators: name: Ghaddar, Abbas
name: Langlais, Philippe
name: Rashid, Ahmad
name: Rezagholizadeh, Mehdi
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: In this work, we examine the ability of NER models to use contextual information when predicting the type of an ambiguous entity. We introduce NRB, a new testbed carefully designed to diagnose Name Regularity Bias of NER models. Our results indicate that all state-of-the-art models we tested show such a bias; BERT fine-tuned models significantly outperforming feature-based (LSTM-CRF) ones on NRB, despite having comparable (sometimes lower) performance on standard benchmarks. To mitigate this bias, we propose a novel model-agnostic training method that adds learnable adversarial noise to some entity mentions, thus enforcing models to focus more strongly on the contextual signal, leading to significant gains on NRB. Combining it with two other training strategies, data augmentation and parameter freezing, leads to further gains.
description: MIT Press\TACL 2021\Presented at ACL 2021 This is the exact same content of the TACL version, except the figures and tables are better aligned
Viscous cosmology in the Weyl-type $f(Q,T)$ gravity
Creators: name: Gadbail, Gaurav
name: Arora, Simran
name: Sahoo, P. K.
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Bulk viscosity is the only viscous influence that can change the background dynamics in a homogeneous and isotropic universe. In the present work, we analyze the bulk viscous cosmological model with the bulk viscosity coefficient of the form $ξ=ξ_0+ξ_1H+ξ_2\left(\frac{\dot{H}}{H}+H\right)$ where, $ξ_0$, $ξ_1$ and $ξ_2$ are bulk viscous parameters, and $H$ is the Hubble parameter. We investigate the impact of the bulk viscous parameter on dynamics of the universe in the recently proposed Weyl type $f(Q, T)$ gravity, where $Q$ is the non-metricity, and $T$ is the trace of the matter energy-momentum tensor. The exact solutions to the corresponding field equations are obtained with the viscous fluid and the linear gravity model of the form $f(Q, T)=αQ+\fracβ{6κ^2}T$, where $α$ and $β$ are model parameters. Further, we constrain the model parameters using the $57$ points Hubble dataset and recently released 1048 points Pantheon sample, which shows our model is good congeniality with observations. We study the possible scenarios and the evolution of the universe through the deceleration parameter, the statefinder diagnostics, the Om diagnostics. It is observed that the universe exhibits a transition from a decelerated to an accelerated phase of the universe under certain constraints of model parameters.
description: EPJC revised version
Superfluid and Pseudo-Goldstone Modes in Three Flavor Crystalline Color Superconductivity
Creators: name: Anglani, R.
name: Gatto, R.
name: Ippolito, N. D.
name: Nardulli, G.
name: Ruggieri, M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study the bosonic excitations in the favorite cubic three flavor crystalline LOFF phases of QCD. We calculate in the Ginzburg-Landau approximation the masses of the eight pseudo Nambu-Goldstone Bosons (NGB) present in the low energy theory. We also compute the decay constants of the massless NGB Goldstones associated to superfluidity as well as those of the eight pseudo NGB. Differently from the corresponding situation in the Color-Flavor-Locking phase, we find that meson condensation phases are not expected in the present scenario.
description: 10 pages, RevTeX4 class. Section IIIA enlarged, to appear on Phys. Rev. D
On detecting CP violation in a single neutrino oscillation channel at very long baselines
Creators: name: Latimer, D. C.
name: Escamilla, J.
name: Ernst, D. J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We propose a way of detecting CP violation in a single neutrino oscillation channel at very long baselines (on the order of several thousands of kilometers), given precise knowledge of the smallest mass-squared difference. It is shown that CP violation can be characterized by a shift in $L/E$ of the peak oscillation in the $ν_e$--$ν_μ$ appearance channel, both in vacuum and in matter. In fact, matter effects enhance the shift at a fixed energy. We consider the case in which sub-GeV neutrinos are measured with varying baseline and also the case of a fixed baseline. For the varied baseline, accurate knowledge of the absolute neutrino flux would not be necessary; however, neutrinos must be distinguishable from antineutrinos. For the fixed baseline, it is shown that CP violation can be distinguished if the mixing angle $θ_{13}$ were known.
description: 8 pages, 9 figures; minor typos corrected
Uniform deterministic equivalent of additive functionals and non-parametric drift estimation for one-dimensional recurrent diffusions
Creators: name: Loukianova, D.
name: Loukianov, O.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: Usually the problem of drift estimation for a diffusion process is considered under the hypothesis of ergodicity. It is less often considered under the hypothesis of null-recurrence, simply because there are fewer limit theorems and existing ones do not apply to the whole null-recurrent class. The aim of this paper is to provide some limit theorems for additive functionals and martingales of a general (ergodic or null) recurrent diffusion which would allow us to have a somewhat unified approach to the problem of non-parametric kernel drift estimation in the one-dimensional recurrent case. As a particular example we obtain the rate of convergence of the Nadaraya--Watson estimator in the case of a locally Hölder-continuous drift.
description: Published in at http://dx.doi.org/10.1214/07-AIHP141 the Annales de l'Institut Henri Poincar\'e - Probabilit\'es et Statistiques (http://www.imstat.org/aihp/) by the Institute of Mathematical Statistics (http://www.imstat.org)
A new approach to analyzing solar coronal spectra and updated collisional ionization equilibrium calculations. II. Additional ionization rate coefficients
Creators: name: Bryans, P.
name: Landi, E.
name: Savin, D. W.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have reanalyzed SUMER observations of a parcel of coronal gas using new collisional ionization equilibrium (CIE) calculations. These improved CIE fractional abundances were calculated using state-of-the-art electron-ion recombination data for K-shell, L-shell, Na-like, and Mg-like ions of all elements from H through Zn and, additionally, Al- through Ar-like ions of Fe. They also incorporate the latest recommended electron impact ionization data for all ions of H through Zn. Improved CIE calculations based on these recombination and ionization data are presented here. We have also developed a new systematic method for determining the average emission measure ($EM$) and electron temperature ($T_e$) of an isothermal plasma. With our new CIE data and our new approach for determining average $EM$ and $T_e$, we have reanalyzed SUMER observations of the solar corona. We have compared our results with those of previous studies and found some significant differences for the derived $EM$ and $T_e$. We have also calculated the enhancement of coronal elemental abundances compared to their photospheric abundances, using the SUMER observations themselves to determine the abundance enhancement factor for each of the emitting elements. Our observationally derived first ionization potential (FIP) factors are in reasonable agreement with the theoretical model of Laming (2008).
description: 147 pages (102 of which are online only tables and figures). Submitted to ApJ. Version 2 is updated addressing the referee's report
A Magnetohydrodynamic Boost for Relativistic Jets
Creators: name: Mizuno, Yosuke
name: Hardee, Philip
name: Hartmann, Dieter H.
name: Nishikawa, Ken-Ichi
name: Zhang, Bing
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We performed relativistic magnetohydrodynamic simulations of the hydrodynamic boosting mechanism for relativistic jets explored by Aloy & Rezzolla (2006) using the RAISHIN code. Simulation results show that the presence of a magnetic field changes the properties of the shock interface between the tenuous, overpressured jet ($V^z_j$) flowing tangentially to a dense external medium. Magnetic fields can lead to more efficient acceleration of the jet, in comparison to the pure-hydrodynamic case. A ``poloidal'' magnetic field ($B^z$), tangent to the interface and parallel to the jet flow, produces both a stronger outward moving shock and a stronger inward moving rarefaction wave. This leads to a large velocity component normal to the interface in addition to acceleration tangent to the interface, and the jet is thus accelerated to larger Lorentz factors than those obtained in the pure-hydrodynamic case. Likewise, a strong ``toroidal'' magnetic field ($B^y$), tangent to the interface but perpendicular to the jet flow, also leads to stronger acceleration tangent to the shock interface relative to the pure-hydrodynamic case. Overall, the acceleration efficiency in the ``poloidal'' case is less than that of the ``toroidal'' case but both geometries still result in higher Lorentz factors than the pure-hydrodynamic case. Thus, the presence and relative orientation of a magnetic field in relativistic jets can significant modify the hydrodynamic boost mechanism studied by Aloy & Rezzolla (2006).
description: 25 pages, 10 figures, accepted for publication in ApJ
La construcción de agenda política desde la acción ejercida por los gobiernos locales
Creators: name: Castillo, Daniela
name: Fernández, Ignacia
name: Yáñez, Rodrigo
name: García, Daniela
name: Albacete, Miguel
Publisher: name: Zenodo
Year: 2021
Subjects: Gobiernos locales
COVID-19
América Latina

description: El brote del COVID-19 ha desencadenado una serie de medidas políticas y económicas sin precedentes para intentar contener su expansión. Con algunos meses de desfase respecto de Asia y Europa, desde marzo del 2020 América Latina ha comenzado a aplicar progresivamente medidas para enfrentar la crisis sanitaria, comenzando por la declaración de estados de emergencia, que otorgan al gobierno central el poder y la capacidad para centralizar una serie de decisiones que, en otras condiciones, requieren de la consulta y participación de otros poderes y niveles de gobierno.
Near band-edge luminescence of semi-insulating undoped gallium arsenide at high levels of excitation
Creators: name: Kovalenko, V. F.
name: Shutov, S. V.
name: Baganov, Ye. A.
name: Smyikalo, M. M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The dependences of the maximum and the half-width of near band-edge photoluminescence of semi-insulating undoped GaAs crystals at 77K on the concentration of background acceptor impurities and the level of excitation in the range from 3x1021 to 6x1022 quantum/(cm2/s) are investigated. The observed dependences are explained by formation of the density tails of states as a result of fluctuations of impurity concentration and participation of localized states of the donor impurity band in radiative transitions. Reduction of many-particle interaction at increasing of N can be connected with increasing of shielding of charge carriers by atoms of impurity.
description: 6 pages, 3 figures
Analysis of kinetic freeze out temperature and transverse flow velocity in nucleus-nucleus and proton-proton collisions at same center of mass energy
Creators: name: Waqas, M.
name: Peng, G. X
name: Wazir, Z.
name: Lao, Hailing
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Transverse momentum spectra of different types of identified charged particles in central Gold-Gold (Au-Au) collisions, and inelastic (INEL) or non-single-diffrative (NSD) proton-proton (pp) collisions at the Relativistic Heavy Ion Collider (RHIC), as well as in central and peripheral Lead-Lead (Pb-Pb) collisions, and INEL or NSD pp collisions at the Large Hadron Collider (LHC) are analyzed by the blast wave model with Tsallis statistics. The model results are approximately in agreement with the experimental data measured by STAR, PHENIX and ALICE Collaborations in special transverse momentum ranges. Kinetic freeze out temperature and transverse flow velocity are extracted from the transverse momentum spectra of the particles. It is shown that kinetic freeze out temperature of the emission source depends on mass of the particles, which reveals the mass differential kinetic freeze out scenario in collisions at RHIC and LHC. Furthermore, the kinetic freeze out temperature and transverse flow velocity in central nucleus-nucleus (AA) collisions are larger than in peripheral collisions, and both of them are slightly larger in peripheral nucleus-nucleus collisions or almost equivalent to that in pp proton-proton collisions at the same center of mass energy which shows their similar thermodynamic nature.
Ultra-cold atoms in an optical cavity: two-mode laser locking to the cavity avoiding radiation pressure
Creators: name: Bux, Simone
name: Krenz, Gordon
name: Slama, Sebastian
name: Zimmermann, Claus
name: Courteille, Philippe W.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The combination of ultra-cold atomic clouds with the light fields of optical cavities provides a powerful model system for the development of new types of laser cooling and for studying cooperative phenomena. These experiments critically depend on the precise tuning of an incident pump laser with respect to a cavity resonance. Here, we present a simple and reliable experimental tuning scheme based on a two-mode laser spectrometer. The scheme uses a first laser for probing higher-order transversal modes of the cavity having an intensity minimum near the cavity's optical axis, where the atoms are confined by a magnetic trap. In this way the cavity resonance is observed without exposing the atoms to unwanted radiation pressure. A second laser, which is phase-locked to the first one and tuned close to a fundamental cavity mode drives the coherent atom-field dynamics.
description: 7 pages, 7 figures
Automatic tempered posterior distributions for Bayesian inversion problems
Creators: name: Martino, L.
name: Llorente, F.
name: Curbelo, E.
name: Lopez-Santiago, J.
name: Miguez, J.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computation (stat.CO)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: We propose a novel adaptive importance sampling scheme for Bayesian inversion problems where the inference of the variables of interest and the power of the data noise is split. More specifically, we consider a Bayesian analysis for the variables of interest (i.e., the parameters of the model to invert), whereas we employ a maximum likelihood approach for the estimation of the noise power. The whole technique is implemented by means of an iterative procedure, alternating sampling and optimization steps. Moreover, the noise power is also used as a tempered parameter for the posterior distribution of the the variables of interest. Therefore, a sequence of tempered posterior densities is generated, where the tempered parameter is automatically selected according to the actual estimation of the noise power. A complete Bayesian study over the model parameters and the scale parameter can be also performed. Numerical experiments show the benefits of the proposed approach.
Gravitational spin-orbit dynamics at the fifth-and-a-half post-Newtonian order
Creators: name: Khalil, Mohammed
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: Accurate waveform models are crucial for gravitational-wave data analysis, and since spin has a significant effect on the binary dynamics, it is important to improve the spin description in these models. In this paper, we derive the spin-orbit (SO) coupling at the fifth-and-a-half post-Newtonian (5.5PN) order. The method we use splits the conservative dynamics into local and nonlocal-in-time parts, then relates the local-in-time part to gravitational self-force results by exploiting the simple mass-ratio dependence of the post-Minkowskian expansion of the scattering angle. We calculate the nonlocal contribution to the 5.5PN SO dynamics to eighth order in the small-eccentricity expansion for bound orbits, and to leading order in the large-eccentricity expansion for unbound orbits. For the local contribution, we obtain all the 5.5PN SO coefficients from first-order self-force results for the redshift and spin-precession invariants, except for one unknown that could be fixed in the future by second-order self-force results. However, by incorporating our 5.5PN results in the effective-one-body formalism and comparing its binding energy to numerical relativity, we find that the remaining unknown has a small effect on the SO dynamics, demonstrating an improvement in accuracy at that order.
description: 19 pages, 1 figure, ancillary file. v2: minor improvements, matches published version
Deflection and gravitational lensing of null and timelike signals in general asymptotically (anti-)de Sitter spacetimes
Creators: name: Li, Zixiao
name: Liu, Haotian
name: Jia, Junji
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: The deflection and gravitational lensing of light and massive particles in arbitrary static, spherically symmetric and asymptotically (anti-)de Sitter spacetimes are considered in this work. We first proved that for spacetimes whose metric satisfying certain conditions, the deflection of null rays with fixed closest distance will not depend on the cosmological constant $Λ$, while that of timelike signals and the apparent angle in gravitational lensing still depend on $Λ$. A two-step perturbative method is then developed to compute the change of the angular coordinate and total travel time in the weak field limit. The results are quasi-series of two small quantities, with the finite distance effect of the source/detector naturally taken into account. These results are verified by applying to some known de Sitter spacetimes. Using an exact gravitational lensing equation, we solved the apparent angles of the images and time delays between them and studied the effect of $Λ$ on them. It is found that generally, a small positive $Λ$ will decrease the apparent angle of images from both sides of the lens and increase the time delay between them. The time delay between signals from the same side of the lens but with different energy however, will be decreased by $Λ$.
description: 20 pages, 5 figures
UV and optical emission lines from the z=2.6 radio galaxy 0828+193: spatially resolved measurements
Creators: name: Humphrey, A.
name: Iwamuro, F.
name: Villar-Martin, M.
name: Binette, L.
name: Fosbury, R.
name: Alighieri, S. di Serego
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present an investigation into the spatial variation of the rest-frame UV and optical line and continuum emission along the radio axis of the z=2.6 radio galaxy 0828+193, using long-slit spectra from the Keck II and Subaru telescopes. Line brightnesses, line ratios and electron temperatures are examined, and their relationship with the arm-length asymmetry of the radio source is also investigated. We find that on the side of the nucleus with the shortest radio lobe, the gas covering factor is higher, and the ionization parameter is lower. The contrasts in environmental density required to explain the asymmetries in the line brightness and the radio arm-length asymmetries are in fair agreement with each other. These results add further weight to the conclusion of McCarthy, van Breugel & Kapahi (1991) - lobe distance asymmetries in powerful radio sources are the result of an asymmetry in the environmental density. We also note that the brightness of both the UV and optical continuum emission shows a similar spatial asymmetry to that shown by the line emission. While the UV continuum asymmetry can be wholly explained by the expected asymmetry in the nebular continuum, the optical continuum asymmetry cannot. We argue that, at least at optical wavelengths, the starlight and/or the scattered light must also be strongly spatially asymmetric.
description: Accepted for publication in MNRAS
Chromomagnetic Instability and Gluonic Phase in Dense Neutral Quark Matter
Creators: name: Kiriyama, O.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss the chromomagnetic instability problem in the 2SC/g2SC phases and explore the phase structure of the gluonic phase which is a candidate for the ground state of dense neutral quark matter.
description: 6 pages, 5 figures, talk given at YITP international symposium on Fundamental Problems in Hot and/or Dense QCD, Kyoto, Japan, 3-6 Mar 2008
Discovery of Gas Accretion Onto Stars in 13 Myr old h and chi Persei
Creators: name: Currie, Thayne
name: Kenyon, Scott
name: Balog, Zoltan
name: Bragg, Ann
name: Tokarz, Susan
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We report the discovery of accretion disks associated with ~ 13 Myr-old intermediate/low-mass stars in h and chi Persei. Optical spectroscopy of ~ 5000 stars in these clusters and a surrounding halo population reveal 32 A-K stars with H(alpha) emission. Matching these stars with 2MASS and optical photometry yields 25 stars with the highest probability of cluster membership and EW(H(alpha)) > 5 angstroms. Sixteen of these sources have EW(H(alpha)) > 10 angstroms. The population of accreting sources is strongly spectral type dependent: H(alpha) emission characteristic of accretion, especially strong accretion (EW(H(alpha)) > 10 angstroms), is much more prevalent around stars later than G0. Strong H(alpha) emission from accretion is typically associated with redder Ks-[8] colors. The existence of accreting pre-main sequence stars in h and chi Persei implies that circumstellar gas in some systems, especially those with primaries later than G5 spectral type, can last longer than 10-15 Myr.
description: 12 pages, 3 figures, accepted for publication in The Astrophysical Journal Letters, updated references
Forbidden territories in the string landscape
Creators: name: Kumar, Alok
name: Mukhopadhyay, Subir
name: Ray, Koushik
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Problems of stabilizing moduli of the type--IIB string theory on toroidal orientifolds $\T^6/\Z_2$, in presence of worldvolume fluxes on various D-branes, are considered. For $Z_2$ actions, introducing either O9 or O3 planes, we rule out the possibility of moduli stabilization in a wide class of models with $\mathcal{N}=1$ supersymmetry, characterized by the type of fluxes turned on along D-brane worldvolume. Our results, in particular, imply that Abelian worldvolume fluxes can not by themselves stabilize closed string moduli, in a consistent supersymmtric model, for above orientifold compactifications. We also discuss other $Z_2$ orientifolds of $T^6$ and show that certain other brane wrappings are also ruled out by similar consistency requirements. In specific setups we consider examples with D9-branes wrapping on a complex three-torus with its world-volume fluxes taken to be semi-homogeneous bundles and D7-branes wrapping holomorphic four-cycles of the complex three-torus carrying world-volume fluxes.
description: 18 pages, LaTeX, significantly expanded to incorporate some more cases
Formation of Moving Magnetic Features and Penumbral Magnetic Fields with Hinode/SOT
Creators: name: Kubo, Masahito
name: Ichimoto, Kiyoshi
name: Shimizu, Toshifumi
name: Tsuneta, Saku
name: Suematsu, Yoshinori
name: Katsukawa, Yukio
name: Nagata, Shin'ichi
name: Tarbell, Theodore D
name: Shine, Richard A
name: Title, Alan M
name: Frank, Zoe A
name: Lites, Bruce W
name: Elmore, David
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Vector magnetic fields of moving magnetic features (MMFs) are well observed with the Solar Optical Telescope (SOT) aboard the Hinode satellite. We focus on the evolution of three MMFs with the SOT in this study. We found that an MMF having relatively vertical fields with polarity same as the sunspot is detached from the penumbra around the granules appeared in the outer penumbra. This suggests that granular motions in the outer penumbra are responsible for the disintegration of the sunspot. Two MMFs with polarity opposite to the sunspot are located around the outer edge of horizontal fields extending from the penumbra. This is an evidence that the MMFs with polarity opposite to the sunspot are prolongation of penumbral horizontal fields. Radshifts larger than sonic velocity in the photosphere are detected for some of the MMFs with polarity opposite to the sunspot.
description: 7 pages, 6 figures, accepted for publication in PASJ (Hinode Special Issue)
PREEMPTIVIDADE E OTIMIZAÇÃO NA DINÂMICA EXTENSIONISTA REMOTA
Creators: name: MAIQUEL E SILVA GOMES
name: Ana Carolina Mariano Castrioto
name: Maria de Lourdes dos Santos Antunes
name: Miriam Assunção de Souza Lepcsh
Publisher: name: Zenodo
Year: 2020

description: The university extension promotes, in addition to extensive academic learning, the contact of the student with new fields of knowledge, both with professors from the institution itself and other external organizations that already operate in the professional market, especially those that have ample prominence in the labor field. Of thatIn this way, from the pandemic moment that the country is experiencing, the need to introduce preemptiveness and optimization in the remote extensionist dynamics of the Actuarial Sciences course at the Universidade Federal Fluminense (UFF) prevails, in order, in addition to aiming at efficiency in planning, at the same time the achievement of the stipulated goals is sought through effective processes. This study aims to analyze this need to introduce these mechanisms in the remote extensionist dynamics.
Contact Angle of an Evaporating Droplet of Binary Solution on a Super Wetting Surface
Creators: name: Wu, Mengmeng
name: Doi, Masao
name: Man, Xingkun
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We study the dynamics of contact angle of a droplet of binary solution evaporating on a super wetting surface. Recent experiments show that although equilibrium contact angle of such droplet is zero, the contract angle can show complex time dependence before reaching the equilibrium value. We analyse such phenomena by extending our previous theory for the dynamics of an evaporating single component droplet to double component droplet. We show that the time dependence of the contact angle can be quite complex. Typically, it first decreases slightly, and then increases and finally decreases again. Under certain conditions, we find that the contact angle remains constant over a certain period of time during evaporation. We study how the plateau or peak contact angle depends on the initial composition and the humidity. The theory explains experimental results reported previously.
description: 19 pages, 5 figures, to be published in Soft Matter
Quantum dynamics of N-methylacetamide studied by the vibrational configuration interaction method
Creators: name: Fujisaki, Hiroshi
name: Yagi, Kiyoshi
name: Hirao, Kimihiko
name: Straub, John E.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Biomolecules (q-bio.BM)
subject: FOS: Biological sciences

description: Vibrational energy transfer of the amide I mode of N-methylacetamide (NMA) is studied theoretically using the vibrational configuration interaction method. A quartic force field of NMA is constructed at the B3LYP/6-31G+(d) level of theory and its accuarcy is checked by comparing the resulting anharmonic frequencies with available theoretical and experimental values. Quantum dynamics calculations for the amide I mode excitation clarify the dominant energy transfer pathways, which sensitively depend on the anharmonic couplings among vibrational modes. A ratio of the anharmonic coupling to the frequency mismatch is employed to predict and interpret the dominant energy flow pathways.
description: 13 pages, 4 figures, 2 tables, to be published in Chem. Phys. Lett
Leptogenesis and fermion mass fit in a renormalizable $SO(10)$ model
Creators: name: Mummidi, V. Suryanarayana
name: Patel, Ketan M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: A non-supersymmetric renormalizable $SO(10)$ model is investigated for its viability in explaining the observed fermion masses and mixing parameters along with the baryon asymmetry produced via thermal leptogenesis. The Yukawa sector of the model consists of complex $10_H$ and $\overline{126}_H$ scalars with a Peccei-Quinn like symmetry and it leads to strong correlations among the Yukawa couplings of all the standard model fermions including the couplings and masses of the right-handed (RH) neutrinos. The latter implies the necessity to include the second lightest RH neutrino and flavor effects for the precision computation of leptogenesis. We use the most general density matrix equations to calculate the temperature evolution of flavoured leptonic asymmetry. A simplified analytical solution of these equations, applicable to the RH neutrino spectrum predicted in the model, is also obtained which allows one to fit the observed baryon to photon ratio along with the other fermion mass observables in a numerically efficient way. The analytical and numerical solutions are found to be in agreement within a factor of ${\cal O}(1)$. We find that the successful leptogenesis in this model does not prefer any particular value for leptonic Dirac and Majorana CP phases and the entire range of values of these observables is found to be consistent. The model specifically predicts (a) the lightest neutrino mass $m_{ν_1}$ between 2-8 meV, (b) the effective mass of neutrinoless double beta decay $m_{ββ}$ between 4-10 meV, and (c) a particular correlation between the Dirac and one of the Majorana CP phases.
description: 26 pages, 4 captioned figures, 2 tables; a reference and a few explanatory sentences are added;Published version
Catapagurus undetermined
Creators: name: Celia, Maria
name: Malay, D.
name: Miller, Allison K.
name: Komai, Tomoyuki
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Paguridae
Catapagurus
Catapagurus undetermined

description: Catapagurus sp.
Material. 1 male (SIO-BIC C14512), Pagan Island, station AKM-PAG-04.
Remarks. The sole specimen represents an undescribed species of Catapagurus, which will be described as a new species in a separate paper (Komai et al., in preparation).
description: Published as part of Celia, Maria, Malay, D., Miller, Allison K. & Komai, Tomoyuki, 2021, Hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) of the Northern Marianas, including new records and an updated checklist, pp. 1-29 in Micronesica 2021 (1) on page 13, DOI: 10.5281/zenodo.12118323