Miracle-dz/UniFAR-FTUs huggingface dataset:
THE BLACK HOLE MASS IN THE BRIGHTEST CLUSTER GALAXY NGC 6086

We present the first direct measurement of the central black hole mass, M•, in NGC 6086, the Brightest Cluster Galaxy (BCG) in A2162. Our investigation demonstrates for the first time that stellar-dynamical measurements of M• in BCGs are possible beyond the nearest few galaxy clusters. We observed NGC 6086 with laser guide star adaptive optics and the integral-field spectrograph (IFS) OSIRIS at the W. M. Keck Observatory and with the seeing-limited IFS GMOS-N at Gemini Observatory North. We combined the IFS data sets with existing major-axis kinematics and used axisymmetric stellar orbit models to determine M• and the R-band stellar mass-to-light ratio, M⋆/LR. We find M• = 3.6+1.7−1.1 × 109 M☉ and M⋆/LR = 4.6+0.3−0.7 M☉ L☉−1 (68% confidence) from models using the most massive dark matter halo allowed within the gravitational potential of the host cluster. Models fitting only IFS data confirm M• ∼ 3 × 109 M☉ and M⋆/LR ∼ 4 M☉ L☉−1, with weak dependence on the assumed dark matter halo structure. When data out to 19 kpc are included, the unrealistic omission of dark matter causes the best-fit black hole mass to decrease dramatically, to 0.6 × 109 M☉, and the best-fit stellar mass-to-light ratio to increase to 6.7 M☉ L−1☉,R. The latter value is at further odds with stellar population studies favoring M⋆/LR ∼ 2 M☉ L−1☉. Biases from dark matter omission could extend to dynamical models of other galaxies with stellar cores, and revised measurements of M• could steepen the empirical scaling relationships between black holes and their host galaxies.
Second-generation stars in globular clusters from rapid radiative cooling of pre-supernova massive star winds

Following work by Wunsch and collaborators, we investigate a self-enrichment scenario for second generation star formation in globular clusters wherein wind material from first generation massive stars rapidly radiatively cools. Radiative energy loss allows retention of fast winds within the central regions of clusters, where it fuels star formation. Secondary star formation occurs in $\sim3-5$ Myr, before supernovae, producing uniform iron abundances in both populations. We derive the critical criteria for radiative cooling of massive star winds and the second generation mass as a function of cluster mass, radius, and metallicity. We derive a critical condition on $M/R$, above which second generation star formation can occur. We speculate that above this threshold the strong decrease in the cluster wind energy and momentum allows ambient gas to remain from the cluster formation process. We reproduce large observed second generation fractions of $\sim30-80\%$ if wind material mixes with ambient gas. Importantly, the mass of ambient gas required is only of order the first generation's stellar mass. Second generation helium enrichment $\Delta Y$ is inversely proportional to mass fraction in the second generation; a large second generation can form with $\Delta Y\sim0.001-0.02$, while a small second generation can reach $\Delta Y\sim0.16$. Like other self-enrichment models for the second generation, we are not able to simultaneously account for both the full range of the Na-O anticorrelation and the second generation fraction.
Approaches to the sign problem in lattice field theory

Quantum field theories (QFTs) at finite densities of matter generically involve complex actions. Standard Monte-Carlo simulations based upon importance sampling, which have been producing quantitative first principle results in particle physics for almost fourty years, cannot be applied in this case. Various strategies to overcome this so-called Sign Problem or Complex Action Problem were proposed during the last thirty years. We here review the sign problem in lattice field theories, focussing on two more recent methods: Dualization to world-line type of representations and the density-of-states approach.
On the Nature of Off-limb Flare Continuum Sources Detected by SDO/HMI

The Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory has provided unique observations of off-limb flare emission. White-light continuum enhancements were detected in the “continuum” channel of the Fe 6173 Å line during the impulsive phase of the observed flares. In this paper we aim to determine which radiation mechanism is responsible for such enhancement being seen above the limb, at chromospheric heights around or below 1000 km. Using a simple analytical approach, we compare two candidate mechanisms, the hydrogen recombination continuum (Paschen) and the Thomson continuum due to scattering of disk radiation on flare electrons. Both mechanisms depend on the electron density, which is typically enhanced during the impulsive phase of a flare as the result of collisional ionization (both thermal and also non-thermal due to electron beams). We conclude that for electron densities higher than 1012 cm−3, the Paschen recombination continuum significantly dominates the Thomson scattering continuum and there is some contribution from the hydrogen free–free emission. This is further supported by detailed radiation-hydrodynamical (RHD) simulations of the flare chromosphere heated by the electron beams. We use the RHD code FLARIX to compute the temporal evolution of the flare-heating in a semi-circular loop. The synthesized continuum structure above the limb resembles the off-limb flare structures detected by HMI, namely their height above the limb, as well as the radiation intensity. These results are consistent with recent findings related to hydrogen Balmer continuum enhancements, which were clearly detected in disk flares by the IRIS near-ultraviolet spectrometer.
Comparing galactic satellite properties in hydrodynamical and N-body simulations

In this work, we examine the different properties of galactic satellites in hydrodynamical and pure dark matter simulations. We use three pairs of simulations (collisional and collisionless) starting from identical initial conditions. We concentrate our analysis on pairs of satellites in the hydro and N-body runs that form from the same Lagrangian region. We look at the radial positions, mass-loss as a function of time and orbital parameters of these ‘twin’ satellites. We confirm an overall higher radial density of satellites in the hydrodynamical runs, but find that trends in the mass-loss and radial position of these satellites in the inner and outer region of the parent halo differ from the pure dark matter case. In the outskirts of the halo (≈70 per cent of the virial radius), satellites experience a stronger mass-loss and higher dynamical friction in pure dark matter runs. The situation is reversed in the central region of the halo, where hydrodynamical satellites have smaller apocentre distances and suffer higher mass stripping. We partially ascribe this bimodal behaviour to the delayed infall time for hydro satellites, which on average cross the virial radius of the parent halo 0.7 Gyr after their dark matter twins. Finally, we briefly discuss the implications of the different set of satellite orbital parameters and mass-loss rates in hydrodynamical simulations within the context of thin-disc heating and destruction.
Simulation of Z(3) walls and string production via bubble nucleation in a quark-hadron transition

We study the dynamics of confinement-deconfinement phase transition in the context of relativistic heavy-ion collisions within the framework of effective models for the Polyakov loop order parameter. We study the formation of Z(3) walls and associated strings in the initial transition from the confining (hadronic) phase to the deconfining [quark-gluon plasma (QGP)] phase via the so-called Kibble mechanism. Essential physics of the Kibble mechanism is contained in a sort of domain structure arising after any phase transition which represents random variation of the order parameter at distances beyond the typical correlation length. We implement this domain structure by using the Polyakov loop effective model with a first order phase transition and confine ourselves with temperature/time ranges so that the first order confinement-deconfinement transition proceeds via bubble nucleation, leading to a well defined domain structure. The formation of Z(3) walls and associated strings results from the coalescence of QGP bubbles expanding in the confining background. We investigate the evolution of the Z(3) wall and string network. We also calculate the energy density fluctuations associated with Z(3) wall network and strings which decay away after the temperature drops below the quark-hadron transition temperature during the expansion of QGP. We discuss evolution ofmore » these quantities with changing temperature via Bjorken's hydrodynamical model and discuss possible experimental signatures resulting from the presence of Z(3) wall network and associate strings. « less
On the relation between local and geometric Lagrangians for higher spins

Equations of motion for free higher-spin gauge fields of any symmetry can be formulated in terms of linearised curvatures. On the other hand, gauge invariance alone does not fix the form of the corresponding actions which, in addition, either contain higher derivatives or involve inverse powers of the d'Alembertian operator, thus introducing possible subtleties in degrees of freedom count. We suggest a path to avoid ambiguities, starting from local, unconstrained Lagrangians previously proposed, and integrating out the auxiliary fields from the functional integral, thus generating a unique non-local theory expressed in terms of curvatures.
Gravitational and distributed heating effects of a cD galaxy on the hydrodynamical structure of its host cluster

We investigate the effects of a cD galaxy’s gravity and AGN heating of the host galaxy cluster. We consider a standard prescription for the hydrodynamics, with the structures determined by mass continuity, momentum and energy conservation equations in spherical symmetry. The cluster comprises a dark matter halo (DM) and ionized X-ray emitting intracluster gas (ICM), which jointly determine the gravitational potential. The cD galaxy is an additive gravitational potential component. The DM assumes a polytropic equation of state (determined by its microphysics), which could be nonradiative self-interacting particles or more exotically interacting particles. The AGN provides distributed heating, counteracting radiative cooling. Stationary density and velocity dispersion profiles are obtained by numerically integrating the hydrodynamic equations with appropriate boundary conditions. The minimum gas temperature in the cluster core is higher when a cD galaxy is present than when it is absent. The solutions also yield a point-like mass concentration exceeding a minimum mass: presumably the AGN’s supermassive black hole (SMBH). Consistency with observed SMBH masses constrains the possible DM equations of state. The constraints are looser when a cD galaxy is present. Distributed (AGN) heating alters cluster global properties, and also reduces the lower limits for the central point-mass, for the preferred DM models in which the dark particles have greater heat capacity than point particles. Eluding these constraints would require dominant non-spherical or anisotropic effects (e.g. bulk rotation, non-radial streaming, asymmetric lumps or a strong magnetic field).
Natural Groundwater Systems Can Display Chaotic Mixing at the Darcy Scale

Although steady, isotropic Darcy flows are inherently laminar and non-mixing, it is well understood that transient forcing via engineered pumping schemes can induce rapid, chaotic mixing in groundwater. In this study we explore the propensity for such mixing to arise in natural groundwater systems subject to cyclical forcings, e.g. tidal or seasonal influences. Using a conventional linear groundwater flow model subject to tidal forcing, we show that under certain conditions these flows generate Lagrangian transport and mixing phenomena (chaotic advection) near the tidal boundary. We show that aquifer heterogeneity, storativity, and forcing magnitude cause reversals in flow direction over the forcing cycle which, in turn, generate coherent Lagrangian structures and chaos. These features significantly augment fluid mixing and transport, leading to anomalous residence time distributions, flow segregation, and the potential for profoundly altered reaction kinetics. We define the dimensionless parameter groups which govern this phenomenon and explore these groups in connection with a set of well-characterised coastal systems. The potential for Lagrangian chaos to be present near discharge boundaries must be recognized and assessed in field studies.
Evolution of a Pulsar Wind Nebula within a Composite Supernova Remnant

The interaction between a pulsar wind nebula (PWN) and its host supernova remnant (SNR) can produce a vast array of observable structures. Asymmetry present within these structures derives from the complexity of the composite system, where many factors take turns playing a dominating hand throughout the stages of composite SNR evolution. Of particular interest are systems characterized by blastwave expansion within a nonuniform interstellar medium (ISM), which contain an active pulsar having a substantial “kick” velocity (upward of 300 km s − 1 ), because these systems tend to produce complex morphologies. We present a numerical model that employs these and several other factors in an effort to generate asymmetry similar to that seen in various X-ray and radio observations. We find that the main parameters driving structure are ISM uniformity and total pulsar spin-down energy, with secondary contributions from factors such as pulsar trajectory and initial spin-down luminosity. We also investigate the dynamics behind PWN “tails,” which may form to link active pulsars to a crushed, relic nebula as the reverse shock passes. We find that the directions of such tails are not good indicators of pulsar motion, but direction does reveal the flow of ejecta created by the passage of a reverse shock.
Relativistic stars in f(R) and scalar-tensor theories

We study relativistic stars in the context of scalar-tensor theories of gravity that try to account for the observed cosmic acceleration and satisfy the local gravity constraints via the chameleon mechanism. More specifically, we consider two types of models: scalar-tensor theories with an inverse power law potential and f(R) theories. Using a relaxation algorithm, we construct numerically static relativistic stars, both for constant energy density configurations and for a polytropic equation of state. We can reach a gravitational potential up to {Phi}{approx}0.3 at the surface of the star, even in f(R) theories with an 'unprotected' curvature singularity. However, we find static configurations only if the pressure does not exceed one third of the energy density, except possibly in a limited region of the star (otherwise, one expects tachyonic instabilities to develop). This constraint is satisfied by realistic equations of state for neutron stars.
Uncovering the progenitor of the Cetus stream with StarGO -- a low mass dwarf with a nuclear star cluster

We use a novel cluster identification tool StarGO to explore the metal poor ([Fe/H] $ $ 15 kpc) of the Milky Way using data from Gaia, LAMOST and SDSS. Our method is built using an unsupervised learning algorithm, a self-organizing map, which trains a 2-D neural network to learn the topological structures of a data set from an n-D input space. Using a 4-D space of angular momentum and orbital energy, we identify three distinct groups corresponding to the Sagittarius, Orphan, and Cetus Streams. For the first time we are able to discover a northern counterpart to the Cetus stream. We test the robustness of this new detection using mock data and find that the significance is more than 5-sigma. We also find that the existing southern counterpart bifurcates into two clumps with different radial velocities. By exploiting the visualization power of StarGO, we attach MW globular clusters to the same trained neural network. The Sagittarius stream is found to have five related clusters, confirming recent literature studies, and the Cetus stream has one associated cluster, NGC 5824. This latter association has previously been postulated, but can only now be truly confirmed thanks to the high-precision Gaia proper motions and large numbers of stellar spectra from LAMOST. The large metallicity dispersion of the stream indicates that the progenitor cannot be a globular cluster. Given the mean metallicity of the stream, we propose that the stream is the result of a merger of a low-mass dwarf galaxy that hosted a large nuclear star cluster (NGC 5824).
Effect of calcium and boron on biomass yield and nutrients uptake by tomato (Solanum lycopersicum)

A pot experiment was conducted in acid soil (Alfisol) using four levels of lime (CaCO3) based on lime requirement (LR), viz. 0, 1/3, 2/3, and 1 and four levels of boron (B), viz. 0, 1.0, 1.5 and 2 mg/kg to evaluate the effect of applied calcium (Ca) and boron (B) on biomass yield, nutrient uptake of tomato (Solanum lycopersicum L.) and soil properties. The results indicated that application of Ca @ 2/3 LR and 1 LR significantly increased biomass yield of tomato by 21% and 16%, respectively over control. Boron application @ 1.0 mg/kg recorded highest biomass yield (19.6 g/pot) of tomato as compared to other boron treatments. Applied Ca @ 2/3 LR significantly increased the uptake of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulphur (S), zinc (Zn) and copper (Cu), whereas iron (Fe), manganese (Mn) and B uptake increased only up to Ca @ 1/3 LR treatment. Application of B increased the nutrients uptake over control, whereas it was observed significantly higher with B @ 1.5 mg/kg treatment. Applied Ca significantly enhanced the pH and available Ca in post-harvest soil, whereas salicylic acid extractable boron (SAE-B) was declined. The combined application of calcium @ 2/3 LR and B @ 1.5 mg/kg was most effective in enhancing the yield and nutrient uptake of tomato.
Reliability and Validity of Inertial Sensor Assisted Reaction Time Measurement Tools among Healthy Young Adults

The assessment of movement reaction time (RT) as a sideline assessment is a valuable biomarker for mild TBI or concussion. However, such assessments require controlled laboratory environments, which may not be feasible for sideline testing during a game. Body-worn wearable devices are advantageous as being cost-effective, easy to don and use, wirelessly transmit data, and ensure unhindered movement performance. This study aimed to develop a Drop-stick Test System (DTS) with a wireless inertial sensor and confirm its reliability for different standing conditions (Foam versus No Foam) and task types (Single versus Dual), and postures (Standing versus sitting). Fourteen healthy young participants (seven females, seven males; age 24.7 ± 2.6 years) participated in this study. The participants were asked to catch a falling stick attached to the sensor during a drop test. Reaction Times (RTs) were calculated from data for each trial from DTS and laboratory camera system (gold standard). Intraclass correlation coefficients (ICC 3,k) were computed to determine inter-instrument reliability. The RT measurements from participants using the camera system and sensor-based DTS showed moderate to good inter-instrument reliability with an overall ICC of 0.82 (95% CI 0.78–0.85). Bland–Altman plots and 95% levels of agreement revealed a bias where the DTS underestimated RT by approximately 50 ms.
Consequences of Mechanical and Radiative Feedback from Black Holes in Disc Galaxy Mergers

We study the effect of AGN mechanical and radiation feedback on the formation of bulge dominated galaxies via mergers of disc galaxies. The merging galaxies have mass-ratios of 1:1 to 6:1 and include pre-existing hot gaseous halos to properly account for the global impact of AGN feedback. Using smoothed particle hydrodynamics simulation code (GADGET-3) we compare three models with different AGN feedback models: (1) no black hole and no AGN feedback; (2) thermal AGN feedback; and (3) mechanical and radiative AGN feedback. The last model is motivated by observations of broad absorption line quasars which show winds with initial velocities of vw > 10,000 km s 1 and also heating associated with the central AGN X-ray radiation. The primary changes in gas properties due to mechanical AGN feedback are lower thermal X-ray luminosity from the final galaxy - in better agreement with observations - and galactic outflows with higher velocity � 1000 km s 1 similar to recent direct observations of nearby merger remnants. The kinetic energy of the outflowing gas is a factor of � 20 higher than in the thermal feedback case. All merger remnants with momentum-based AGN feedback with vw � 10,000 km s 1 and ǫf = 2 × 10 3 , independent of their progenitor mass-ratios, reproduce the observed relations between stellar velocity dispersion and black hole mass (MBH σ) as well as X-ray luminosity (LX σ) with 10 37.5 . LX(0.3 8 keV)/erg s 1 . 10 39.2 for velocity dispersions in the range of 120 km s 1 . σ . 190 km s 1 . In addition, the mechanical feedback produces a much greater AGN variability. We also show that gas is more rapidly and impulsively stripped from the galactic centres driving a moderate increase in galaxy size and decrease in central density with the mechanical AGN feedback model.
Searching for non‐axisymmetries in NGC 6503: a weak end‐on bar

The isolation, simple apparent structure and low luminosity of the nearby spiral galaxy NGC 6503 make it an ideal candidate for an in-depth kinematic and photometric study. We introduce a new publicly available code, DiskFit, that implements procedures for fitting non-axisymmetries in either kinematic or photometric data. We use DiskFit to analyse new Hα and CO velocity field data as well as H i kinematics from Greisen et al. to search for non-circular motions in the disc of NGC 6503. We find NGC 6503 to have remarkably regular gas kinematics that are well described by rotation only. We also use DiskFit and a new Ks-band image of NGC 6503 to constrain photometric models of the disc, bar and bulge. We find the galaxy to be photometrically dominated by the disc. We find NGC 6503 to contain a faint bar and an exponential bulge which together contribute only ∼5 per cent of the total galaxy light. The combination of our kinematic and photometric DiskFit models suggests that NGC 6503 contains a weak, end-on bar that may have produced its Type II surface brightness profile but is unlikely to be responsible for its strong σ-drop.