cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Polytopes and large counterexamples
Creators: name: Alexandersson, Per
Publisher: name: arXiv
Year: 2016
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 52B12, 05E10

description: In this short note, we give large counterexamples to natural questions about certain order polytopes, in particular, Gelfand--Tsetlin polytopes. Several of the counterexamples are too large to be discovered via a brute-force computer search. We also show that the multiset of hooks in a Young diagram is not enough information to determine the Ehrhart polynomial for an associated order polytope. This is somewhat counter-intuitive to the fact that the multiset of hooks always determine the leading coefficient of the Ehrhart polynomial.
Supervisory Control of Fuzzy Discrete Event Systems for Simulation Equivalence
Creators: name: Deng, Weilin
name: Qiu, Daowen
Publisher: name: arXiv
Year: 2016
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: The supervisory control theory of fuzzy discrete event systems (FDESs) for fuzzy language equivalence has been developed. However, in a way, language equivalence has limited expressiveness. So if the given specification can not be expressed by language equivalence, then the control for language equivalence does not work. In this paper, we further establish the supervisory control theory of FDESs for fuzzy simulation equivalence whose expressiveness is stronger than that of fuzzy language equivalence. First, we formalize the notions of fuzzy simulation and fuzzy simulation equivalence between two FDESs. Then we present a method for deciding whether there is a fuzzy simulation or not. In addition, we also show several basic properties of fuzzy simulation relations. Afterwards, we put forward the notion of fuzzy simulation-based controllability, and particularly show that it serves as a necessary and sufficient condition for the existence of the fuzzy supervisors of FDESs. Moreover, we study the "range" control problem of FDESs. Some examples are given to illustrate the main results obtained.
Efficient spectral computation of the stationary states of rotating Bose-Einstein condensates by the preconditioned nonlinear conjugate gradient method
Creators: name: Antoine, Xavier
name: Levitt, Antoine
name: Tang, Qinglin
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We propose a preconditioned nonlinear conjugate gradient method coupled with a spectral spatial dis-cretization scheme for computing the ground states (GS) of rotating Bose-Einstein condensates (BEC), modeled by the Gross-Pitaevskii Equation (GPE). We first start by reviewing the classical gradient flow (also known as imaginary time (IMT)) method which considers the problem from the PDE standpoint, leading to numerically solve a dissipative equation. Based on this IMT equation, we analyze the forward Euler (FE), Crank-Nicolson (CN) and the classical backward Euler (BE) schemes for linear problems and recognize classical power iterations, allowing us to derive convergence rates. By considering the alternative point of view of minimization problems, we propose the preconditioned gradient (PG) and conjugate gradient (PCG) methods for the GS computation of the GPE. We investigate the choice of the preconditioner, which plays a key role in the acceleration of the convergence process. The performance of the new algorithms is tested in 1D, 2D and 3D. We conclude that the PCG method outperforms all the previous methods, most particularly for 2D and 3D fast rotating BECs, while being simple to implement.
Structural Analysis of Open Cluster Bochum 2
Creators: name: Kaur, Harmeen
name: Sharma, Saurabh
name: Durgapal, Alok
name: Dewangan, Lokesh K
name: Verma, Aayushi
name: Panwar, Neelam
name: Pandey, Rakesh
name: Ghosh, Arpan
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present the results from our deep optical photometric observations of Bochum 2 (Boc2) star cluster obtained using the $1.3$m Devasthal Fast Optical Telescope along with archival photometric data from Pan-STARRS2/2MASS/UKIDSS surveys. We also used high-quality parallax and proper motion data from the $Gaia$ Data Release 3. We found that the Boc2 cluster has a small size ($\sim$1.1 pc) and circular morphology. Using $Gaia$ parallax of member stars and isochrone fitting method, the distance of this cluster is estimated as $3.8\pm0.4$ kpc. We have found that this cluster holds young ($\sim5$ Myr) and massive (O$7-$O$9$) stars as well as an older population of low mass stars. We found that the massive stars have formed in the inner region of the Boc2 cluster in a recent epoch of star formation. We have derived mass function slope ($Γ$) in the cluster region as $-2.42\pm0.13$ in the mass range $\sim0.72<$M/M$_{\odot}<2.8$. The tidal radius of the Boc2 cluster ($\sim7-9$) is much more than its observed radius ($\sim1.1$ pc). This suggests that most of the low-mass stars in this cluster are the remains of an older population of stars formed via an earlier epoch of star formation.
description: accepted for publication in Journal of Astrophysics and Astronomy
Power-2 limb-darkening coefficients for the $uvby$, $UBVRIJHK$, SDSS $ugriz$, Gaia, Kepler, TESS, and CHEOPS photometric systems II. PHOENIX spherically symmetric stellar atmosphere models
Creators: name: Claret, A.
name: Southworth, J.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Multiple parametric limb-darkening laws have been presented, and there are many available sources of theoretical limb-darkening coefficients (LDCs) calculated using stellar model atmospheres. The power-2 limb-darkening law allows a very good representation of theoretically predicted intensity profiles, but few LDCs are available for this law from spherically symmetric model atmospheres. We therefore present such coefficients in this work. We computed LDCs for the space missions \textit{Gaia}, \textit{Kepler}, TESS, and CHEOPS and for the passbands $uvby$, $UBVRIJHK$, and SDSS $ugriz$, using the \textsc{phoenix-cond} spherical models. We adopted two methods to characterise the truncation point, which sets the limb of the star: the first (M1) uses the point where the derivative d$I(r)$/d$r$ is at its maximum where I(r) is the specific intensity as a function of the normalised radius r corresponding to $μ_{\rm cri}$, and the second (M2) uses the midpoint between the point $μ_{\rm cri}$ and the point located at $μ_{\rm cri-1}$. The LDCs were computed adopting the Levenberg-Marquardt least-squares minimisation method, with a resolution of 900 equally spaced $μ$ points, and covering 823 model atmospheres for a solar metallicity, effective temperatures of 2300 to 12000\,K, $\log g$ values from 0.0 to 6.0, and microturbulent velocities of 2\,km\,s$^{-1}$. As our previous calculations of LDCs using spherical models included only 100 $μ$ points, we also updated the calculations for the four-parameter law for the passbands listed above, and compared them with those from the power-2 law. Comparisons between the quality of the fits provided by the power-2 and four-parameter laws show that the latter presents a lower merit function, $χ^2$, than the former for both cases (M1 and M2). This is important when choosing the best approach for a particular science goal.
Synchronization of silicon thermal-free-carrier oscillators
Creators: name: Luiz, Gustavo de O.
name: Rodrigues, Caique C.
name: Alegre, Thiago P. Mayer
name: Wiederhecker, Gustavo S.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Recent exploration of collective phenomena in oscillator arrays has highlighted its potential for accessing a range of physical phenomena, from fundamental quantum many-body dynamics to the solution of practical optimization problems using photonic Ising machines. Spontaneous oscillations often arise in these oscillator arrays as an imbalance between gain and loss. Due to coupling between array individuals, the spontaneous oscillation is constrained and lead to interesting collective behavior, such as synchronized oscillations in optomechanical oscillator arrays, ferromagnetic-like coupling in delay-coupled optical parametric oscillators and binary phase states in coupled laser arrays. A key aspect of arrays is not only the coupling between its individuals but also their compliance towards neighbor stimuli. One self-sustaining photonic oscillator that can be readily implemented in a scalable foundry-based technology is based on the interaction of free-carriers, temperature and optical field of a resonant silicon photonic microcavity. Here we demonstrate that these silicon thermal-free-carrier oscillators are extremely compliant to external excitation and can be synchronized up to their 16$^\text{th}$ harmonic using a weak seed. Exploring this unprecedented compliance to external stimuli, we also demonstrate robust synchronization between two thermal free carrier oscillators.
description: 6 pages, 5 figures, appendix
A Modular Data Acquisition System using the 10 GSa/s PSEC4 Waveform Recording Chip
Creators: name: Bogdan, M.
name: Oberla, E.
name: Frisch, H. J.
name: Wetstein, M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We describe a modular multi-channel data acquisition system based on the 5-15 Gigasample-per-second waveform-recording PSEC4 chip. The system architecture incorporates two levels of hardware with FPGA-embedded system control and in-line data processing. The front-end unit is a 30-channel circuit board that holds five PSEC4 ASICs, a clock jitter cleaner, and a control FPGA. The analog bandwidth of the front-end signal path is 1.5 GHz. Each channel has an on-chip threshold-level discriminator that is monitored in the FPGA, from which a flexible on-board trigger decision can be formed. To instrument larger channel counts, a `back-end' 6U VME32 control card has been designed. Called the 'Central Card', it incorporates an Altera Arria-V FPGA that manages up to 8 front-end cards using one or two CAT5 network cables per board, which transmits the clock and communicates data packets over a custom serial protocol. Data can be read from the Central Card via USB, Ethernet, or dual SFP links, in addition to the VME interface. The Central Card can be configured as either Master or Slave, allowing one Master to receive data from up to 8 Slaves, with each Slave managing 8 30-channel front-end cards, allowing a single VME crate to control up to 1920 channels of the PSEC4 chip.
description: 3 pages, 4 figures, proceedings for the 2016 IEEE-NPSS Real-Time conference in Padova
Disentangling planetary and stellar activity features in the CoRoT-2 light curve
Creators: name: Bruno, G.
name: Deleuil, M.
name: Almenara, J. -M.
name: Barros, S. C. C.
name: Lanza, A. F.
name: Montalto, M.
name: Boisse, I.
name: Santerne, A.
name: Lagrange, A. -M.
name: Meunier, N.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: [Abridged] Context. Stellar activity is an important source of systematic errors and uncertainties in the characterization of exoplanets. Most of the techniques used to correct for this activity focus on an ad hoc data reduction. Aims. We have developed a software for the combined fit of transits and stellar activity features in high-precision long-duration photometry. Our aim is to take advantage of the modelling to derive correct stellar and planetary parameters, even in the case of strong stellar activity. Methods. We use an analytic approach to model the light curve. The code KSint, modified by adding the evolution of active regions, is implemented into our Bayesian modelling package PASTIS. The code is then applied to the light curve of CoRoT-2. The light curve is divided in segments to reduce the number of free parameters needed by the fit. We perform a Markov chain Monte Carlo analysis in two ways. In the first, we perform a global and independent modelling of each segment of the light curve, transits are not normalized and are fitted together with the activity features, and occulted features are taken into account during the transit fit. In the second, we normalize the transits with a model of the non-occulted activity features, and then we apply a standard transit fit, which does not take the occulted features into account. Results. Our model recovers the activity features coverage of the stellar surface and different rotation periods for different features. We find variations in the transit parameters of different segments and show that they are likely due to the division applied to the light curve. Neglecting stellar activity or even only bright spots while normalizing the transits yields a $\sim 1.2σ$ larger and $2.3σ$ smaller transit depth, respectively. The stellar density also presents up to $2.5σ$ differences depending on the normalization technique...
description: 14 pages, 7 figures, 6 tables, accepted on A&A. arXiv admin note: text overlap with arXiv:1604.03979
The diffuse radio emission in the high-redshift cluster PSZ2 G091.83+26.11: total intensity and polarisation analysis with Very Large Array 1-4 GHz observations
Creators: name: Di Gennaro, G.
name: Brüggen, M.
name: van Weeren, R. J.
name: Simionescu, A.
name: Brunetti, G.
name: Cassano, R.
name: Forman, W. R.
name: Hoeft, M.
name: Ignesti, A.
name: Röttgering, H. J. A.
name: Shimwell, T. W.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present the peculiar case of PSZ2G091.83+26.11 at z=0.822. This cluster hosts a Mpc-scale radio halo and an elongated radio source, whose location with the respect to the intracluster medium (ICM) distribution and to the cluster centre is not consistent with a simple merger scenario. We use VLA data at 1-4 GHz to investigate the spectral and polarisation properties of the diffuse radio emission. We combine them with previously published data from LOFAR n the 120-168 MHz band, and from the uGMRT at 250-500 and 550-900 MHz. We also complement the radio data with Chandra X-ray observations to compare the thermal and non-thermal emission of the cluster. The elongated radio emission is visible up to 3.0 GHz and has an integrated spectral index of $-1.24\pm0.03$, with a steepening from $-0.89\pm0.03$ to $-1.39\pm0.03$. These values correspond to Mach numbers $\mathcal{M}_{\rm radio,int}=3.0\pm0.19$ and $\mathcal{M}_{\rm radio,inj}=2.48\pm0.15$. Chandra data reveals a surface brightness discontinuity at the location of the radio source, with a compression factor of $\mathcal{C}=2.22^{+0.39}_{-0.30}$ (i.e. $\mathcal{M}_{\rm Xray}=1.93^{+0.42}_{-0.32}$). We also find that the source is polarised at GHz frequencies. We estimate an intrinsic polarisation fraction of $\sim0.2$, a Rotation Measure of $\sim50~{\rm rad~m^{-2}}$ (including the Galactic contribution) and an external depolarisation of $\sim60~{\rm rad~m^{-2}}$. The $B$-vectors are aligned with the major axis of the source, suggesting magnetic field compression. Hence, we classify this source as a radio relic. We also find a linear/super-linear correlation between the non-thermal and thermal emission. We propose an off-axis merger and/or multiple merger events to explain the position and orientation of the relic. Given the properties of the radio relic, we speculate that PSZ2G091.83+26.11 is in a fairly young merger state.
description: 21 pages, 17 figures, 9 tables; accepted for publication in Astronomy & Astrophysics
On the Performance Analysis of Underlay Cognitive Radio Systems: A Deployment Perspective
Creators: name: Kaushik, Ankit
name: Sharma, Shree Krishna
name: Chatzinotas, Symeon
name: Ottersten, Björn
name: Jondral, Friedrich K.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: We study the performance of cognitive Underlay System (US) that employ power control mechanism at the Secondary Transmitter (ST) from a deployment perspective. Existing baseline models considered for performance analysis either assume the knowledge of involved channels at the ST or retrieve this information by means of a band manager or a feedback channel, however, such situations rarely exist in practice. Motivated by this fact, we propose a novel approach that incorporates estimation of the involved channels at the ST, in order to characterize the performance of the US in terms of interference power received at the primary receiver and throughput at the secondary receiver (or \textit{secondary throughput}). Moreover, we apply an outage constraint that captures the impact of imperfect channel knowledge, particularly on the uncertain interference. Besides this, we employ a transmit power constraint at the ST to classify the operation of the US in terms of an interference-limited regime and a power-limited regime. In addition, we characterize the expressions of the uncertain interference and the secondary throughput for the case where the involved channels encounter Nakagami-$m$ fading. Finally, we investigate a fundamental tradeoff between the estimation time and the secondary throughput depicting an optimized performance of the US.
description: 14 pages, 9 figures, accepted for publication in IEEE Transactions on Cognitive Communications and Networking
Axion-photon conversion of GRB221009A
Creators: name: Wang, Luohan
name: Ma, Bo-Qiang
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The newly observed gamma ray burst GRB221009A exhibits the existence of 10~TeV-scale photons, and the axion-photon conversion has been suggested as a candidate to explain such energetic features of GRB221009A. In this work we adopt a model to calculate the conversion probability of the energetic photons from GRB221009A to the Earth. The result shows that the penetration probability of photons with energy above $10^1$~TeV can be up to $10^{-2}$ to $ 10^{-4}$ depending on the coupling constant $g_{aγ}$ and the axion mass $m_a$, together on the magnetic field parameters of the source galaxy of GRB221009A. We show that the parameters of the source galaxy, with the magnetic field handled by a cellular model, contribute a lot of uncertainties to the penetration probability, so we have more freedom to reconcile a variety of axionlike particle parameters from other observations with the Large High Altitude Air Shower Observatory observation. By comparing the results in this article with the data from Large High Altitude Air Shower Observatory, we can obtain more precise constraints on the ranges of these parameters.
description: 9 latex pages, 5 figures, final version for publication
Detections of 21-cm absorption with a blind FAST survey at z $\leqslant$ 0.09
Creators: name: Hu, Wenkai
name: Wang, Yougang
name: Li, Yichao
name: Xu, Yidong
name: Yang, Wenxiu
name: Lagache, Guilaine
name: Pen, Ue-Li
name: Zheng, Zheng
name: Shu, Shuanghao
name: Zheng, Yinghui
name: Li, Di
name: Ching, Tao-Chung
name: Chen, Xuelei
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present the early science results from a blind search of the extragalactic HI 21-cm absorption lines at z $\leqslant$ 0.09 with the drift-scan observation of the Five-hundred-meter Aperture Spherical radio Telescope (FAST). We carried out the search using the data collected in 643.8 hours by the ongoing Commensal Radio Astronomy FasT Survey (CRAFTS), which spans a sky area of 3155 deg$^{2}$ and covers 44827 radio sources with a flux density greater than 12 mJy. Due to the radio frequency interference (RFI), only the relatively clean data in the frequency range of 1.3-1.45 GHz are used in the present work. Under the assumption of $T_{s}/c_{f}$ = 100 K, the total completeness-corrected comoving absorption path length spanned by our data and sensitive to Damped Lyman $α$ Absorbers (DLAs) are $ΔX^{inv}$ = 8.33$\times10^3$ ($Δz^{inv} = 7.81\times10^{3}$) for intervening absorption. For associated absorption, the corresponding values are $ΔX^{asc}$ = 12.8 ($Δz^{asc} = 11.9$). Three known HI absorbers (UGC 00613, 3C 293 and 4C +27.14) and two new HI absorbers (towards NVSS J231240-052547 and NVSS J053118+315412) are detected blindly. We fit the HI profiles with multi-components Gaussian functions and calculate the redshift (0.063, 0.066), width, flux density, optical depth and HI column densities for each absorption. Our results demonstrate the power of FAST in blindly searching HI absorbers. For absorption towards NVSS J231240-052547, the optical counterparts are faint and currently lack existing spectra. The most likely interpretation is that a radio-loud active galactic nucleus (AGN) is faint in the optical as the background source, with a faint optical absorber in between. NVSS J053118+315412 exhibits an associated absorption with a complex profile, which may suggest unsettled gas structures or gas accretion onto the supermassive black hole (SMBH).
description: 18 pages, 19 figures
Quantum avoidance of Gödel's closed timelike curves
Creators: name: Zhao, Zhe
name: Modesto, Leonardo
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In a large class of nonlocal as well as local higher derivative theories minimally coupled to the matter sector, we investigate the exactness of two different classes of homogeneous Gödel-type solutions, which may or may not allow closed time-like curves (CTC). Our analysis is limited to spacetimes solving the Einstein's EoM, thus we can not exclude the presence of other Gödel-type solutions solving the EoM of local and nonlocal higher derivative theories but not the Einstein's EoM.It turns out that the homogeneous Gödel spacetimes without CTC are basically exact solutions for all theories, while the metrics with CTC are not exact solutions of (super-)renormalizable local or nonlocal gravitational theories. Hence, the quantum renormalizability property excludes theories suffering of the Gödel's causality violation. We also comment about nonlocal gravity non-minimally coupled to matter. In this class of theories, all the Gödel's spacetimes, with or without CTC, are exact solutions at classical level. However, the quantum corrections, although perturbative, very likely spoil the exactness of such solutions. Therefore, we can state that the Gödel's Universes with CTC and the super-renormalizability are mutually exclusive.
description: 13 pages
Bi-Fuzzy Discrete Event Systems and Their Supervisory Control Theory
Creators: name: Deng, Weilin
name: Qiu, Daowen
Publisher: name: arXiv
Year: 2016
Subjects: subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: It is well known that type-1 fuzzy sets (T1 FSs) have limited capabilities to handle some data uncertainties directly, and type-2 fuzzy sets (T2 FSs) can cover the shortcoming of T1 FSs to a certain extent. Fuzzy discrete event systems (FDESs) were proposed based on T1 FSs theory. Hence, FDES may not be a satisfactory model to characterize some high-uncertainty systems. In this paper, we propose a new model, called as bi-fuzzy discrete event systems (BFDESs), by combining classical DESs theory and T2 FSs theory. Then, we consider the supervisory control problem of BFDESs. The bi-fuzzy controllability theorem and nonblocking bi-fuzzy controllability theorem are demonstrated. Also, an algorithm for checking the bi-fuzzy controllability condition is presented. In addition, two controllable approximations to an uncontrollable language are investigated in detail. An illustrative example is provided to show the applicability and the advantages of BFDESs model.
description: 14 pages
title: A Stratigraphic Reconstruction of Bulk Volatile Chemistry from Fluid Inclusions in: Jericho 1
Creators: name: C., Boreham
name: S., Cowan
name: C., Boreham
name: M., Duffett
name: D., Hall
name: J., Chao
name: W., Phiukhao
name: R., Lishansky
name: R., Moore
name: D., Groves
name: A., Feitz
name: A., McNeill
name: D., Green
Publisher: name: Commonwealth of Australia (Geoscience Australia)
Year: 2023
Subjects: subject: EARTH SCIENCES
subject: fluid inclusion
subject: thin section
subject: microthemometry
subject: EFTF - Exploring for the Future
subject: National Hydrogen Project
subject: Published_External

description: Exploring for the Future (EFTF) is an Australian Government program led by Geoscience Australia (GA), in partnership with state and Northern Territory governments. The EFTF program (2016-2024) aims to drive industry investment in resource exploration in frontier regions of onshore Australia by providing new precompetitive data and information about their energy, mineral and groundwater resource potential. Under the EFTF program, GA’s National Hydrogen Project and in collaboration with Minerals Resources Tasmania (MRT) undertook a study of hydrogen and helium potential of south-east Tasmania with the sampling of cores from Jericho 1 on Bruny Island. This well was selected based on the availability of core and historic reports of hydrogen-rich natural gases from this well and petroleum exploration wells in the region. Sampling of cores was done at MRT’s Core Repository in Hobart. Geoscience Australia commissioned a fluid inclusion stratigraphy (FIS) study on the downhole samples. Here, volatile components ostensibly trapped with fluid inclusions are released and analysed revealing the level of exposure of the well section to migrating fluids. Integration of thin section (TS) preparations reveal the extent of gas and fluid trapping within fluid inclusions while microthemometry (MT) gives an estimation of fluid inclusion trapping temperature. For Jericho 1, FIS analysis was performed on 179 cores between 87 m and 640.6 m base depth, together with 7 samples prepared for TS and 1 sample for MT. To support this study, lithostratigraphic tops were compiled by MRT. The results of the study are found in the accompanying documents.
Conductance oscillations of antiferromagnetic layer tunnel junctions
Creators: name: Choi, Sang-Jun
name: Sun, Hai-Peng
name: Trauzettel, Björn
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We study the conductance oscillation of an antiferromagnetic layer tunnel junction composed of antiferromagnetic topological insulators (MTIs) such as MnBi$_{2}$Te$_{4}$. In presence of an in-plane magnetic field, we find that the two terminal differential conductance across the junction oscillates as a function of field strength. Notably, the quantum interference at weak fields for the odd-layer MTIs is distinctive from the even-layer MTIs due to the scattering phase difference. Consequently, the differential conductance is vanishing (maximized) at integer magnetic flux quanta for even-layer (odd-layer) junction. The conductance oscillations manifest the layer-dependent quantum interference in which symmetries and scattering phases play essential roles. In numerical calculations, we observe that the quantum interference undergoes an evolution from SQUID-like patterns to Fraunhofer-like oscillations as the junction length increases.
Orthogonality of the mean and error distribution in generalized linear models
Creators: name: Huang, Alan
name: Rathouz, Paul J.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Methodology (stat.ME)
subject: FOS: Computer and information sciences

description: We show that the mean-model parameter is always orthogonal to the error distribution in generalized linear models. Thus, the maximum likelihood estimator of the mean-model parameter will be asymptotically efficient regardless of whether the error distribution is known completely, known up to a finite vector of parameters, or left completely unspecified, in which case the likelihood is taken to be an appropriate semiparametric likelihood. Moreover, the maximum likelihood estimator of the mean-model parameter will be asymptotically independent of the maximum likelihood estimator of the error distribution. This generalizes some well-known results for the special cases of normal, gamma and multinomial regression models, and, perhaps more interestingly, suggests that asymptotically efficient estimation and inferences can always be obtained if the error distribution is nonparametrically estimated along with the mean. In contrast, estimation and inferences using misspecified error distributions or variance functions are generally not efficient.
description: 7 pages, 1 table, Communications in Statistics - Theory and Methods (acc. 20 Sep 2013)
Binary Formation in a 100 $μ$m-dark Massive Core
Creators: name: Kong, Shuo
name: Arce, Héctor G.
name: Tobin, John J.
name: Zhang, Yichen
name: Maureira, María José
name: Kratter, Kaitlin M.
name: Pillai, Thushara G. S.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We report high-resolution ALMA observations toward a massive protostellar core C1-Sa ($\sim$30 M$_\odot$) in the Dragon Infrared Dark Cloud. At the resolution of 140 AU, the core fragments into two kernels (C1-Sa1 and C1-Sa2) with a projected separation of $\sim$1400 AU along the elongation of C1-Sa, consistent with a Jeans length scale of $\sim$1100 AU. Radiative transfer modeling using RADEX indicates that the protostellar kernel C1-Sa1 has a temperature of $\sim$75 K and a mass of 0.55 M$_\odot$. C1-Sa1 also likely drives two bipolar outflows, one being parallel to the plane-of-the-sky. C1-Sa2 is not detected in line emission and does not show any outflow activity but exhibits ortho-H$_2$D$^+$ and N$_2$D$^+$ emission in its vicinity, thus it is likely still starless. Assuming a 20 K temperature, C1-Sa2 has a mass of 1.6 M$_\odot$. At a higher resolution of 96 AU, C1-Sa1 begins to show an irregular shape at the periphery, but no clear sign of multiple objects or disks. We suspect that C1-Sa1 hosts a tight binary with inclined disks and outflows. Currently, one member of the binary is actively accreting while the accretion in the other is significantly reduced. C1-Sa2 shows hints of fragmentation into two sub-kernels with similar masses, which requires further confirmation with higher sensitivity.
description: 7 figures, 2 tables, accepted by ApJ
Linear absorption coefficient of in-plane graphene on a silicon microring resonator
Creators: name: Cai, Heng
name: Cheng, Yahui
name: Zhang, He
name: Huang, Qingzhong
name: Xia, Jinsong
name: Barille, Regis
name: Wang, Yi
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We demonstrate that linear absorption coefficient (LAC) of a graphene-silicon hybrid waveguide (GSHW) is determined by the optical transmission spectra of a graphene coated symmetrically coupled add-drop silicon microring resonator (SC-ADSMR), of which the value is around 0.23 dB/um. In contrast to the traditional cut-back method, the measured results are not dependent on the coupling efficiency of the fiber tip and the waveguide. Moreover, precision evaluation of graphene coated silicon microring resonator (SMR) is crucial for the optoelectronic devices targeting for compact footprint and low power consumption.
description: 7 pages, 6 figures, published in Optics Express (2016)
Superheavy Elements in Kilonovae
Creators: name: Holmbeck, Erika M.
name: Barnes, Jennifer
name: Lund, Kelsey A.
name: Sprouse, Trevor M.
name: McLaughlin, G. C.
name: Mumpower, Matthew R.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: As LIGO-Virgo-KAGRA enters its fourth observing run, a new opportunity to search for electromagnetic counterparts of compact object mergers will also begin. The light curves and spectra from the first "kilonova" associated with a binary neutron star binary (NSM) suggests that these sites are hosts of the rapid neutron capture ("$r$") process. However, it is unknown just how robust elemental production can be in mergers. Identifying signposts of the production of particular nuclei is critical for fully understanding merger-driven heavy-element synthesis. In this study, we investigate the properties of very neutron rich nuclei for which superheavy elements ($Z\geq 104$) can be produced in NSMs and whether they can similarly imprint a unique signature on kilonova light-curve evolution. A superheavy-element signature in kilonovae represents a route to establishing a lower limit on heavy-element production in NSMs as well as possibly being the first evidence of superheavy element synthesis in nature. Favorable NSMs conditions yield a mass fraction of superheavy elements is $X_{Z\geq 104}\approx 3\times 10^{-2}$ at 7.5 hours post-merger. With this mass fraction of superheavy elements, we find that the component of kilonova light curves possibly containing superheavy elements may appear similar to those arising from lanthanide-poor ejecta. Therefore, photometric characterizations of superheavy-element rich kilonova may possibly misidentify them as lanthanide-poor events.
description: 8 pages, 5 figures, 4 data tables
The Creative Process in Musical Composition: An Introspective Account
Creators: name: Gabora, Liane
Publisher: name: arXiv
Year: 2016
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Biological sciences

description: This chapter charts the creative process in the composition of a piece of music titled 'Stream not gone dry' that unfolded, while I was primarily occupied with other matters, over the course of nearly two decades. It avoids discussion of the technical aspects of musical composition, and it can be read by someone with no formal knowledge of music. The focus here is on what the process of composing this particular piece of music says about how the creative process works. My interpretation of the music-making process may be biased by my academic view of creativity, but I believe that the influence works primarily in the other direction, my understanding of how the creative process works is derived from experiences creating. This intuitive understanding is shaped over time by the process of reading scholarly papers on creativity and working them into my own evolving theory of creativity, but the papers that I resonate with and incorporate are those that are in line with my experience. This chapter just makes the influence of personal experience more explicit than in other more scholarly writings on creativity.
description: 9 pages
Introducing DataCite Global Access Fund
Creators: name: Mejias, Gabriela
Publisher: name: Zenodo
Year: 2023
Subjects: DataCite, Global Access Program, webinar, Global Access Fund, Open Infrastructure, Digital Object Identifier, DOI, persistent identifier, PID

description: DataCite is thrilled to launch a Global Access Fund (GAF), established to enable organizations worldwide to make their research outputs discoverable. It will provide financial support for outreach activities and infrastructure development to enable more organizations to benefit from DataCite infrastructure services. The GAF is part of the DataCite Global Access Program (GAP) made possible by grant Grant 2022-316573 from the Chan Zuckerberg Initiative. Applications are open to non-profit stakeholders within the research ecosystem (e.g. research institutions, associations, NRENs, government bodies, service providers) based in Africa, Latin America, the Middle East, and Asia. In her presentation, Gabriela Mejias gives an introduction to DataCite's infrastructure. A recording of the presentation can be found here: https://www.youtube.com/watch?v=E37uWZbY-I8&t=122s
Neutron star phase transition as the origin for the fast radio bursts and soft gamma-ray repeaters of SGR J1935+2154
Creators: name: Shen, Jun-Yi
name: Zou, Yuan-Chuan
name: Yang, Shu-Hua
name: Zheng, Xiao-Ping
name: Wang, Kai
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Magnetars are believed as neutron stars (NSs) with strong magnetic fields. X-ray flares and fast radio bursts (FRBs) have been observed from the magnetar (soft gamma-ray repeater, SGR J1935+2154). We propose that the phase transition of the NS can power the FRBs and SGRs.Based on the equation of state provided by the MIT bag model and the mean field approximation, we solve the Tolman-Oppenheimer-Volkoff equations to get the NS structure. With spin-down of the NS, the hadronic shell gradually transfers to the quark shell.The gravitational potential energy released by one time of the phase transition can be achieved. The released energy, time interval between two successive phase transitions, and glitch are all consistent with the observations of the FRBs and the X-ray flares from SGR J1935+2154. We conclude that the phase transition of an NS is a plausible mechanism to power the SGRs as well as the repeating FRBs.
description: 11 pages, 3 figures
A level-set-based topology optimisation for acoustic-elastic coupled problems with a fast BEM-FEM solver
Creators: name: Isakari, Hiroshi
name: Kondo, Toyohiro
name: Takahashi, Toru
name: Matsumoto, Toshiro
Publisher: name: arXiv
Year: 2016
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: This paper presents a structural optimisation method in three-dimensional acoustic-elastic coupled problems. The proposed optimisation method finds an optimal allocation of elastic materials which reduces the sound level on some fixed observation points. In the process of the optimisation, configuration of the elastic materials is expressed with a level set function, and the distribution of the level set function is iteratively updated with the help of the topological derivative. The topological derivative is associated with state and adjoint variables which are the solutions of the acoustic-elastic coupled problems. In this paper, the acoustic-elastic coupled problems are solved by a BEM-FEM coupled solver, in which the fast multipole method (FMM) and a multi-frontal solver for sparse matrices are efficiently combined. Along with the detailed formulations for the topological derivative and the BEM-FEM coupled solver, we present some numerical examples of optimal designs of elastic sound scatterer to manipulate sound waves, from which we confirm the effectiveness of the present method.
description: 19 pages, 15 figures
The Enhanced Resolution Imager and Spectrograph for the VLT
Creators: name: Davies, R.
name: Absil, O.
name: Agapito, G.
name: Berbel, A. Agudo
name: Baruffolo, A.
name: Biliotti, V.
name: Bonaglia, M.
name: Bonse, M.
name: Briguglio, R.
name: Campana, P.
name: Cao, Y.
name: Carbonaro, L.
name: Cortes, A.
name: Cresci, G.
name: Dallilar, Y.
name: Dannert, F.
name: De Rosa, R. J.
name: Deysenroth, M.
name: Di Antonio, I.
name: Di Cianno, A.
name: Di Rico, G.
name: Doelman, D.
name: Dolci, M.
name: Dorn, R.
name: Eisenhauer, F.
name: Esposito, S.
name: Fantinel, D.
name: Ferruzzi, D.
name: Feuchtgruber, H.
name: Finger, G.
name: Schreiber, N. M. Förster
name: Gao, X.
name: Gemperlein, H.
name: Genzel, R.
name: Gillessen, S.
name: Ginski, C.
name: Glauser, A. M.
name: Glindemann, A.
name: Grani, P.
name: Hartl, M.
name: Hayoz, J.
name: Heida, M.
name: Henry, D.
name: Hofmann, R.
name: Huber, H.
name: Kasper, M.
name: Keller, C.
name: Kenworthy, M.
name: Kravchenko, K.
name: Kuntschner, H.
name: Lacour, S.
name: Lightfoot, J.
name: Lunney, D.
name: Lutz, D.
name: Macintosh, M.
name: Mannucci, F.
name: Marsset, M.
name: Modigliani, A.
name: Neeser, M.
name: de Xivry, G. Orban
name: Ott, T.
name: Pallanca, L.
name: Patapis, P.
name: Pearson, D.
name: Peña, E.
name: Percheron, I.
name: Puglisi, A.
name: Quanz, S. P.
name: Rabien, S.
name: Rau, C.
name: Riccardi, A.
name: Salasnich, B.
name: Schmid, H. -M.
name: Schubert, J.
name: Serra, B.
name: Shimizu, T.
name: Snik, F.
name: Sturm, E.
name: Tacconi, L.
name: Taylor, W.
name: Valentini, A.
name: Waring, C.
name: Wiezorrek, E.
name: Xompero, M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: ERIS, the Enhanced Resolution Imager and Spectrograph, is an instrument that both extends and enhances the fundamental diffraction limited imaging and spectroscopy capability for the VLT. It replaces two instruments that were being maintained beyond their operational lifetimes, combines their functionality on a single focus, provides a new wavefront sensing module for natural and laser guide stars that makes use of the Adaptive Optics Facility, and considerably improves on their performance. The observational modes ERIS provides are integral field spectroscopy at 1-2.5 μm, imaging at 1-5 μm with several options for high contrast imaging, and longslit spectroscopy at 3-4 μm, The instrument is installed at the Cassegrain focus of UT4 at the VLT and, following its commissioning during 2022, has been made available to the community.
description: 20 pages with 29 figures; accepted for A&A (minor changes)
Global Access Fund Evaluation and Selection Process
Creators: name: Ba-Essa, Mohamed A.
Publisher: name: Zenodo
Year: 2023
Subjects: webinar, Global Access Program, Global Access Fund, DataCite, Digital Object Identifier, DOI, PID, persistent identifier, Open Research, Open Science, Open Infrastructure

description: DataCite is thrilled to launch a Global Access Fund (GAF), established to enable organizations worldwide to make their research outputs discoverable. It will provide financial support for outreach activities and infrastructure development to enable more organizations to benefit from DataCite infrastructure services. The GAF is part of the DataCite Global Access Program (GAP) made possible by grant Grant 2022-316573 from the Chan Zuckerberg Initiative. Applications are open to non-profit stakeholders within the research ecosystem (e.g. research institutions, associations, NRENs, government bodies, service providers) based in Africa, Latin America, the Middle East, and Asia. In his presentation, Mohamed A. Ba-Essa gives an overview of the GAF evaluation and review processes. A recording of the presentation can be found here: https://www.youtube.com/watch?v=E37uWZbY-I8&t=1579s
Entanglement detection on an NMR quantum information processor using random local measurements
Creators: name: Singh, Amandeep
name: Arvind
name: Dorai, Kavita
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Random local measurements have recently been proposed to construct entanglement witnesses and thereby detect the presence of bipartite entanglement. We experimentally demonstrate the efficacy of one such scheme on a two-qubit NMR quantum information processor. We show that a set of three random local measurements suffices to detect the entanglement of a general two-qubit state. We experimentally generate states with different amounts of entanglement, and show that the scheme is able to clearly witness entanglement. We perform complete quantum state tomography for each state and compute state fidelity to validate our results. Further, we extend previous results and perform a simulation using random local measurements to optimally detect bipartite entanglement in a hybrid system of $2\otimes 3$ dimensionality.
description: 8 pages, 5 figures
NLO cross sections in 4 dimensions without DREG
Creators: name: Hernández-Pinto, R. J.
name: Driencourt-Mangin, F.
name: Rodrigo, G.
name: Sborlini, G. F. R.
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In this review, we present a new method for computing physical cross sections at NLO accuracy in QCD without using the standard Dimensional Regularisation. The algorithm is based on the Loop-Tree Duality theorem, which allow us to obtain loop integrals as a sum of phase-space integrals; in this way, transforming loop integrals into phase-space integrals, we propose a method to merge virtual and real contributions in order to find observables at NLO in $d=4$ space-time dimensions. In addition, the strategy described is used for computing the $γ^*\to q\bar{q}(g)$ process. A more detailed discussion related on this topic can be found in Ref [1].
description: 4 pages. To be published in Journal of Physics Conference Series (IOP). Joint Proceedings of the XV Mexican Workshop on Particles and Fields & the XXX Annual Meeting of the Division of Particles and Fields of the Mexican Physical Society
Carrollian Approach to $1+3$D Flat Holography
Creators: name: Saha, Amartya
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The isomorphism between the (extended) BMS$_4$ algebra and the $1+2$D Carrollian conformal algebra hints towards a co-dimension one formalism of flat holography with the field theory residing on the null-boundary of the asymptotically flat space-time enjoying a $1+2$D Carrollian conformal symmetry. Motivated by this fact, we study the general symmetry properties of a source-less $1+2$D Carrollian CFT, adopting a purely field-theoretic approach. After deriving the position-space Ward identities, we show how the $1+3$D bulk super-translation and the super-rotation memory effects emerge from them, manifested by the presence of a temporal step-function factor in the same. Temporal-Fourier transforming these memory effect equations, we directly reach the bulk null-momentum-space leading and sub-leading soft graviton theorems. Along the way, we construct six Carrollian fields $S^\pm_0$, $S^\pm_1$, $T$ and $\bar{T}$ corresponding to these soft graviton fields and the Celestial stress-tensors, purely in terms of the Carrollian stress-tensor components. The 2D Celestial shadow-relations and the null-state conditions arise as two natural byproducts of these constructions. We then show that those six fields consist of the modes that implement the super-rotations and a subset of the super-translations on the quantum fields. The temporal step-function allows us to relate the operator product expansions (OPEs) with the operator commutation relations via a complex contour integral prescription. We deduce that not all of those six fields can be taken together to form consistent OPEs. So choosing $S^+_0$, $S^+_1$ and $T$ as the local fields, we form their mutual OPEs using only the OPE-commutativity property, under two general assumptions. The symmetry algebra manifest in these holomorphic-sector OPEs is then shown to be $\text{Vir}\ltimes\hat{\overline{\text{sl}(2,\mathbb{R})}}$ with an abelian ideal.
description: Section 3.3 is revised and contains a new result. Added references