Miracle-dz/UniFAR-FTUs huggingface dataset:
Diffracto-Astrometry Measurements: Accuracy of the Measuring Algorithm

We present a theoretical analysis of the measuring algorithm we use when applying the diffracto-astrometry technique to Hubble Space Telescope Wide Field Planetary Camera 2 (WFPC2) saturated stellar images. Theoretical point-spread functions (PSFs) were generated using the Tiny Tim software for the four CCDs in the WFPC2 and for some of the available filters. These images were then measured with our diffracto-astrometry measuring algorithm using only their diffraction pattern, and positions for the simulated PSFs on each generated CCD frame were obtained. The measuring algorithm recovers the original positions reasonably well (± 0.1 to ± 0.4 pixels). However, slight deviations from the original values are observed. These also vary with position over the entire surface of the CCD. We adjust the difference between the real and the measured positions with a quadratic function of the coordinates. The transformation coefficients also present a slight correlation with the filter effective wavelength. Application of these transformation coefficients allows us to determine the position of a stellar image with a precision of a few hundredths of a pixel.
A Novel Transmitter-Interpulse Phase Coding MIMO-Radar for Range Ambiguity Separation

The range ambiguity issue is a technical challenge in the radar community and has been widely discussed over the years. Researchers have given special attention to multiple-input multiple-output (MIMO) radar to address the range ambiguity because this radar system can employ more equivalent degrees of freedom. Open studies on MIMO radar are generally based on the assumption of orthogonal waveforms, whereas radar performance is seriously limited by distributed targets due to mismatched energy. To this end, this article deals with a novel MIMO radar transmission scheme called transmitter interpulse phase coding (TIPC) without using orthogonal waveforms. First, a set of well-designed TIPC codes are employed to modulate transmitter subarrays with the same modulated signal. Second, in the case of high pulse repetition frequency (PRF), aliased echoes from different transmitted channels are directly separated by a group of simple Doppler filters; for normal PRF radar systems, a technique called digital beamforming in azimuth is exploited to ensure an effective multiple waveform separation. Third, a decoding processing is performed for a further derivation of the residual TIPC matrix that is related with ambiguity order. Next, the desired and ambiguous echoes are separated by a specifically designed spatial filter that absorbs the residual TIPC matrix. Particularly, the separated signal can be used for some further applications such as increasing the observation swath. Finally, point-like target and distributed targets simulation experiments are performed to verify the feasibility of the proposed TIPC MIMO radar.
Note on SU(2) isolated horizon

We point out that the symplectic structure, written in terms of the Sen–Ashtekar–Immirzi–Barbero variables, of a spacetime admitting an isolated horizon as the inner boundary, involves a positive constant parameter, say σ, if γ ≠ ±i, where γ is the Barbero–Immirzi parameter. The parameter σ represents the rescaling freedom that characterizes the equivalence class of null generators of the isolated horizon. We reiterate the fact that the laws of mechanics associated with the isolated horizon does not depend on the choice of σ and, in particular, while one uses the value of standard surface gravity as input, that does not fix σ to a particular value. This fact contradicts the claims made in certain parts of the concerned literature that we duly refer to. We do the calculations by taking Schwarzschild metric as an example so that the contradiction with the referred literature, where similar approaches were adopted, becomes apparent. The contribution to the symplectic structure that comes from the isolated horizon, diverges for σ2=(1+γ2)−1, implying that the rescaling symmetry of the isolated horizon is violated for any real γ. Since the quantum theory of SU(2) isolated horizon in the LQG framework exists only for real values of γ, it is founded on this flawed classical setup. Nevertheless, if the flaw is ignored, then two different viewpoints persist in the literature for entropy calculation. We highlight the main features of those approaches and point out why one is logically viable and the other is not.
Cavity Optomechanics

We review the field of cavity optomechanics, which explores the interaction between electromagnetic radiation and nano- or micromechanical motion. This review covers the basics of optical cavities and mechanical resonators, their mutual optomechanical interaction mediated by the radiation pressure force, the large variety of experimental systems which exhibit this interaction, optical measurements of mechanical motion, dynamical backaction amplification and cooling, nonlinear dynamics, multimode optomechanics, and proposals for future cavity quantum optomechanics experiments. In addition, we describe the perspectives for fundamental quantum physics and for possible applications of optomechanical devices.
Emergent Friedmann equation from the evolution of cosmic space revisited

Following the recent study on the emergent Friedmann equation from the expansion of cosmic space for a flat universe, we apply this method to a nonflat universe, and modify the evolution equation to lead to the Friedmann equation. In order to maintain the same form with the original evolution equation, we have to define the time-dependent Planck length, which shows that the spatial curvature of k = 0 and k = 1 is preferable to k = 1 since the Planck length of the nonflat open universe is divergent. Finally, we discuss its physical consequences.
A SUBMILLIMETER PERSPECTIVE ON THE GOODS FIELDS. II. THE HIGH RADIO POWER POPULATION IN THE GOODS-N

We use ultradeep 20 cm data from the Karl G. Jansky Very Large Array and 850 μm data from SCUBA-2 and the Submillimeter Array of an 124 arcmin2 region of the Chandra Deep Field-north to analyze the high radio power ( erg s−1 Hz−1) population. We find that 20 (42 ± 9%) of the spectroscopically identified sources have consistent star formation rates (SFRs) inferred from both submillimeter and radio observations, while the remaining sources have lower (mostly undetected) submillimeter fluxes, suggesting that active galactic nucleus (AGN) activity dominates the radio power in these sources. We develop a classification scheme based on the ratio of submillimeter flux to radio power versus radio power and find that it agrees with AGN and star-forming galaxy classifications from Very Long Baseline Interferometry. Our results provide support for an extremely rapid drop in the number of high SFR galaxies above about a thousand solar masses per year (Kroupa initial mass function) and for the locally determined relation between X-ray luminosity and radio power for star-forming galaxies applying at high redshifts and high radio powers. We measure far-infrared (FIR) luminosities and find that some AGNs lie on the FIR-radio correlation, while others scatter below. The AGNs that lie on the correlation appear to do so based on their emission from the AGN torus. We measure a median radio size of 1. ″0 ± 0.3 for the star-forming galaxies. The radio sizes of the star-forming galaxies are generally larger than those of the AGNs.
Enhancement of coil--stretch hysteresis by self-concentration in extensional flows, and its implications for capillary thinning of liquid bridges of dilute polymer solutions

The coil-stretch transition in extensional flows of viscoelastic dilute polymer solutions is known to be associated with a strong hysteresis in molecular conformations and rheo-optical properties. At infinite dilution, hysteresis is caused by the large difference in frictional drag coefficient between undeformed isotropic polymer coils and highly stretched conformations. At the low extension rates in the hysteresis regime, stretched molecules pervade larger volumes than equilibrium coils since the flow is too weak to suppress transverse fluctuations. The onset of intermolecular overlap occurs for such stretched conformations at polymer concentrations much smaller than c*, the conventional critical overlap concentration for equilibrium coils. Therefore, for a range of concentrations c < c*, intramolecular hydrodynamic interactions may be significantly screened in stretched conformations. Scaling arguments based on "blob" concepts are used here to argue that the stretched state drag coefficient can grow strongly with concentration in the dilute regime. A dumbbell model with conformation-dependent drag model is used to predict a concomitant strong enhancement of coil-stretch hysteresis with increasing concentration in the dilute regime. This extensional flow induced self-concentration leads to a maximum in hysteretic effects around c*, which progressively diminish in the semi-dilute regime where screening in isotropic coils reduces the difference in drag coefficient between stretched and coiled states. It is shown that the concentration dependence observed by Clasen et al. (2006) of capillary-thinning dynamics in liquid bridges of polymer solutions provides direct evidence of coil-stretch hysteresis enhancement by self-concentration.
GIANT X-RAY BUMP IN GRB 121027A: EVIDENCE FOR FALL-BACK DISK ACCRETION

A particularly interesting discovery in observations of GRB 121027A is that of a giant X-ray bump detected by the Swift/X-Ray Telescope. The X-ray afterglow re-brightens sharply at ∼103 s after the trigger by more than two orders of magnitude in less than 200 s. This X-ray bump lasts for more than 104 s. It is quite different from typical X-ray flares. In this Letter we propose a fall-back accretion model to interpret this X-ray bump within the context of the collapse of a massive star for a long-duration gamma-ray burst. The required fall-back radius of ∼3.5 × 1010 cm and mass of ∼0.9–2.6 M☉ imply that a significant part of the helium envelope should survive through the mass loss during the last stage of the massive progenitor of GRB 121027A.
Multi-qubit quantum phase gates based on surface plasmons of a nanosphere

The Dicke subradiance and superradiance resulting from the interaction between surface plasmons of a nanosphere and an ensemble of quantum emitters have been investigated using a Green’s function approach. Based on such an investigation, we propose a scheme for a deterministic multi-qubit quantum phase gate. As an example, two-qubit, three-qubit, and four-qubit quantum phase gates have been designed and analyzed in detail. Phenomena due to the losses in the metal are discussed. Potential applications of these phenomena to quantum-information processing are anticipated.
Inclusive diffraction at the LHeC and FCC-eh

Néstor Armesto, Paul R. Newman, Wojciech S lomiński, and Anna M. Staśto Instituto Galego de F́ısica de Altas Enerx́ıas IGFAE, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Galicia-Spain School of Physics and Astronomy, University of Birmingham, UK Institute of Physics, Jagiellonian University, Krakow, Poland Department of Physics, Penn State University, University Park, PA 16802, USA
COLLAPSE OF MASSIVE MAGNETIZED DENSE CORES USING RADIATION MAGNETOHYDRODYNAMICS: EARLY FRAGMENTATION INHIBITION

We report the results of radiation-magnetohydrodynamics calculations in the context of high-mass star formation, using for the first time a self-consistent model for photon emission (i.e., via thermal emission and in radiative shocks) and with the high resolution necessary to properly resolve magnetic braking effects and radiative shocks on scales <100 AU. We investigate the combined effects of magnetic field, turbulence, and radiative transfer on the early phases of the collapse and the fragmentation of massive dense cores. We identify a new mechanism that inhibits initial fragmentation of massive dense cores where magnetic field and radiative transfer interplay. We show that this interplay becomes stronger as the magnetic field strength increases. Magnetic braking is transporting angular momentum outward and is lowering the rotational support and is thus increasing the infall velocity. This enhances the radiative feedback owing to the accretion shock on the first core. We speculate that highly magnetized massive dense cores are good candidates for isolated massive star formation while moderately magnetized massive dense cores are more appropriate forming OB associations or small star clusters.
Imaginary part of the gravitational action at asymptotic boundaries and horizons

We study the imaginary part of the Lorentzian gravitational action for bounded regions, as described in arXiv:1301.7041. By comparing to a Euclidean calculation, we explain the agreement between the formula for this imaginary part and the formula for black hole entropy. We also clarify the topological structure of the imaginary part in Lovelock gravity. We then evaluate the action's imaginary part for some special regions. These include cylindrical slabs spanning the exterior of a stationary black hole spacetime, 'maximal diamonds' in various symmetric spacetimes, as well as local near-horizon regions. In the first setup, the black hole's entropy and conserved charges contribute to the action's imaginary and real parts, respectively. In the other two setups, the imaginary part coincides with the relevant entropy.
A Smart Direct Load Control Approach Using Dynamic Voltage Control for Demand Response Programs

Abstract —This study proposes a direct load control (DLC) approach for residential demand response (DR) programs, which uses a dynamic voltage control method to reduce the peak electricity consumption in homes. In the proposed approach, if a utility needs to reduce electrical load consumption, a DLC signal is sent to a smart meter (SM) either via utility’s communication infrastructure. SM communicates with a group of smart plugs attached to selected domestic appliances to individually reduce the output voltage. The electrical consumption of selected appliances can be reduced without turning them OFF. Hence, the peak demand of a residential house can be reduced without turning off selected power-intensive loads, like in a classic direct load control (DLC) approach used by several electric utilities. The proposed dynamic voltage control is operated can be done within a certain limit defined set by international standards to avoid any possible negative impacts on domestic appliances. The results indicated that the proposed DLC could reduce the peak electricity demand up to around 32% using both voltage control and renewable energy. The proposed approach is expected to give flexibility to utilities to control the electrical demand of homes while ensuring participants remain more comfortable during a DR event.
Astrophysical tests of gravity: a screening map of the nearby universe

Astrophysical tests of modified gravity theories in the nearby universe have been emphasized recently by Hui 2009 and Jain 2011. A key element of such tests is the screening mechanism whereby general relativity is restored in massive halos or high density environments like the Milky Way. In chameleon theories of gravity, including all f(R) models, field dwarf galaxies may be unscreened and therefore feel an extra force, as opposed to screened galaxies. The first step to study differences between screened and unscreened galaxies is to create a 3D screening map. We use N-body simulations to test and calibrate simple approximations to determine the level of screening in galaxy catalogs. Sources of systematic errors in the screening map due to observational inaccuracies are modeled and their contamination is estimated. We then apply our methods to create a map out to 200 Mpc in the Sloan Digital Sky Survey footprint using data from the Sloan survey and other sources. In two companion papers this map will be used to carry out new tests of gravity using distance indicators and the disks of dwarf galaxies. We also make our screening map publicly available.
SPHERICALLY SYMMETRIC NLTE MODEL ATMOSPHERES OF HOT HYDROGEN–HELIUM FIRST STARS

We present results of our calculations of NLTE model stellar atmospheres for hot Population III stars composed of hydrogen and helium. We use our own computer code for the calculation of spherically symmetric NLTE model atmospheres in hydrostatic and radiative equilibrium. The model atmospheres are then used for the calculation of emergent fluxes. These fluxes serve to evaluate the flow of high-energy photons for energies higher than ionization energies of hydrogen and helium, the so-called ionizing photon fluxes. We also present the time evolution of the ionizing photon fluxes.
The ionized and hot gas in M17 SW: SOFIA/GREAT THz observations of [C II] and 12CO J=13-12

With new THz maps that cover an area of ~3.3x2. 1 pc^2 we probe the spatial distribution and association of the ionized, neutral and molecular gas components in the M17 SW nebula. We used the dual band receiver GREAT on board the SOFIA airborne telescope to obtain a 5'. 7x3'. 7 map of the 12CO J=13-12 transition and the [C II] 158 um fine-structure line in M17 SW and compare the spectroscopically resolved maps with corresponding ground-based data for low- and mid-J CO and [C I] emission. For the first time SOFIA/GREAT allow us to compare velocity-resolved [C II] emission maps with molecular tracers. We see a large part of the [C II] emission, both spatially and in velocity, that is completely non-associated with the other tracers of photon-dominated regions (PDR). Only particular narrow channel maps of the velocity-resolved [C II] spectra show a correlation between the different gas components, which is not seen at all in the integrated intensity maps. These show different morphology in all lines but give hardly any information on the origin of the emission. The [C II] 158 um emission extends for more than 2 pc into the M17 SW molecular cloud and its line profile covers a broader velocity range than the 12CO J=13-12 and [C I] emissions, which we interpret as several clumps and layers of ionized carbon gas within the telescope beam. The high-J CO emission emerges from a dense region between the ionized and neutral carbon emissions, indicating the presence of high-density clumps that allow the fast formation of hot CO in the irradiated complex structure of M17 SW. The [C II] observations in the southern PDR cannot be explained with stratified nor clumpy PDR models.
Prediction of PM2.5 Dispersion in Bangkok Pathumwan District) Using CFD Modeling

City configuration, meteorological conditions and emission source are the important factors affecting the dispersion and concentration of pollutants within urban street canyon. The dispersion of PM2.5 emitted from traffic in Pathumwan district, Bangkok which has the characteristics of street canyon was predicted using a Computational Fluid Dynamics (CFD) model with the RANS standard k-epsilon turbulence model. The studied area covers the area with high aspect ratio such as the shopping center area with the skytrain structure. The Discrete Phase Model (DPM) was used for simulating the PM2.5 injection and dispersion. The concentrations of PM2.5 were investigated under different conditions to demonstrate the effects of skytrain structure in the street canyon, meteorological conditions, and city lockdown due to the COVID-19 pandemic on PM2.5 concentration. The numerical model was validated with the measured data from the air quality monitoring station of the Environment Bureau, Bangkok. The reduction of emission rate during the city lockdown causes the PM2.5 concentration to decrease by 1.35 times from the normal time. In addition, the city configuration with the skytrain structure located between the tall buildings results in higher PM2.5 concentration than the case without the skytrain structure in Pathumwan district by around 1.2 times. Moreover, the meteorological conditions must be considered, especially wind speed and direction. Finally, the results obtained from the simulation will be used for proposing the guidelines to reduce the concentration of PM2.5.
Anticancer, antioxidant and antibacterial activities of extracts from Scrophularia striata and Elaeagnus angustifolia, growing in Ilam and Kurdistan provinces in Iran

Emerging evidence of the impact of plant compounds on growth inhibition of micropathogens and cancer cells has opened new areas to evaluate plants’ treatment properties. Here, we aimed to investigate in vitro antioxidant, antibacterial and anticancer effects of the secondary metabolites isolated from different extracts produced by Elaeagnus angustifolia and Scrophularia striata. Antibacterial activity was evaluated against human and plant pathogenic bacteria by 3 methods of tubular dilution, well and disc diffusion. The anticancer effect of E. angustifolia extract was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Biochemical experiments showed the presence of compounds such as phenol, flavonoids, resins, quinones, steroids, terpenoids and alkaloids in extracts, with the highest antioxidant activity of the methanolic extracts. For both plants’ strains, the disc method was more effective than the well diffusion method. The highest yields were obtained from Methanolic, ethanolic and hydroalcoholic extracts for E. angustifolia and aqueous extract for Scrophularia striata. The most sensitive bacteria for E. angustifolia were Bacillus subtilis and Xanthomonas campestris against pit extracts and Clavibacter michiganensis against pulp extracts. The most sensitive bacteria for S. striata were Bacillus subtilis and Staphylococcus aureus. Methanolic and aqueous solvents showed the maximum bacterial inhibitory and bactericidal activities in the Minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) tests respectively. Additionally, E. angustifolia showed anticancer effects toward MCF7 breast cancer cells. These findings provided a better understanding of the widespread application of these plants as potential antioxidants, antibacterial and anticancer sources and safe natural medicines in health maintenance and disease treatment.
Long-range interactions between polar alkali-metal diatoms in external electric fields

We computed the long-range interactions between two identical polar bialkali molecules in their rovibronic ground level for all ten species involving Li, Na, K, Rb, and Cs, using accurate quantum chemistry results combined with available spectroscopic data. A huge van der Waals interaction is found for eight species in free space. The competition of the van der Waals interaction with the dipole-dipole interaction induced by an external electric field parallel or perpendicular to the intermolecular axis is investigated by varying the electric-field magnitude and the intermolecular distance. Our calculations predict a regime with the mutual orientation of the two molecules but with no preferential direction in the laboratory frame. A mechanism for the stimulated one-photon radiative association of a pair of ultracold polar molecules into ultracold tetramers is proposed, which would open the way towards the optical manipulation of ultracold polyatomic molecules.