Miracle-dz/UniFAR-FTUs huggingface dataset:
COLDz: Shape of the CO Luminosity Function at High Redshift and the Cold Gas History of the Universe

We report the first detailed measurement of the shape of the CO luminosity function at high redshift, based on >320 hr of the NSF’s Karl G. Jansky Very Large Array (VLA) observations over an area of ∼60 arcmin2 taken as part of the CO Luminosity Density at High Redshift (COLDz) survey. COLDz “blindly” selects galaxies based on their cold gas content through CO(J = 1 → 0) emission at z ∼ 2–3 and CO(J = 2 → 1) at z ∼ 5–7 down to a CO luminosity limit of log( /K km s−1 pc2) ≃ 9.5. We find that the characteristic luminosity and bright end of the CO luminosity function are substantially higher than predicted by semi-analytical models, but consistent with empirical estimates based on the infrared luminosity function at z ∼ 2. We also present the currently most reliable measurement of the cosmic density of cold gas in galaxies at early epochs, i.e., the cold gas history of the universe, as determined over a large cosmic volume of ∼375,000 Mpc3. Our measurements are in agreement with an increase of the cold gas density from z ∼ 0 to z ∼ 2–3, followed by a possible decline toward z ∼ 5–7. These findings are consistent with recent surveys based on higher-J CO line measurements, upon which COLDz improves in terms of statistical uncertainties by probing ∼50–100 times larger areas and in the reliability of total gas mass estimates by probing the low-J CO lines accessible to the VLA. Our results thus appear to suggest that the cosmic star formation rate density follows an increased cold molecular gas content in galaxies toward its peak about 10 billion years ago, and that its decline toward the earliest epochs is likely related to a lower overall amount of cold molecular gas (as traced by CO) bound in galaxies toward the first billion years after the Big Bang.
Interaction between Ionized and Molecular Gas in the Active Star-forming Region W31

We have carried out 21 cm radio continuum, H76α radio recombination line, and various (12CO, 13CO, CS, and C34S) molecular line observations of the W31 complex. Our radio continuum data show that W31 is composed of two extended H II regions, G10.2-0.3 and G10.3-0.1, each of which comprises an ultracompact H II region, two or more compact components, and a diffuse envelope. The W31 cloud appears as an incomplete shell on the whole and consists of southern spherical and northern flat components, which are associated with G10.2-0.3 and G10.3-0.1, respectively. For an assumed distance of 6 kpc, the molecular cloud has a size of 48 pc and a mass of 6.2 × 105 M☉. The IR luminosity-to-mass ratio and the star formation efficiency are derived to be 9 L☉/M☉ and 3%, respectively. These estimates are greater than average values of the inner Galactic plane. We detect two large (16 and 11 pc) and massive (2.1 × 105 and 8.2 × 104 M☉) CS-emitting regions in the northern and southern cloud components. The large amount (48% in mass and 16% in area) of dense gas may suggest that the W31 cloud has the ability to form rich stellar clusters and that star formation has only recently begun. The extended envelopes of both G10.2-0.3 and G10.3-0.1 are likely to be results of the champagne flows, based on the distributions of ionized and molecular gas and the velocity gradient of H76α line emission. According to the champagne model, the dynamical ages of the two H II regions would be (4-12) × 105 yr. We find strong evidence of bipolar molecular outflows associated with the two ultracompact H II regions. In the vicinity of the ultracompact and compact H II regions in G10.3-0.1, the 12CO J = 2-1/J = 1-0 intensity ratio is high (1.4), and a small but prominent molecular gas hollow exists. Together, these observations strongly indicate that the H II regions and their ionizing stars are interacting with the molecular cloud. Therefore, it is most likely that recently formed massive stars are actively disrupting their parental molecular cloud in the W31 complex.
Hunting for Radio Emission from the Intermittent Pulsar J1107-5907 at Low Frequencies

Rare intermittent pulsars pose some of the most challenging questions surrounding the pulsar emission mechanism, but typically have relatively minimal low-frequency (≲300 MHz) coverage. We present the first low-frequency detection of the intermittent pulsar J1107–5907 with the Murchison Widefield Array (MWA) at 154 MHz and the simultaneous detection from the recently upgraded Molonglo Observatory Synthesis Telescope (UTMOST) at 835 MHz, as part of an ongoing observing campaign. During a 30 minute simultaneous observation, we detected the pulsar in its bright emission state for approximately 15 minutes, where 86 and 283 pulses were detected above a signal-to-noise threshold of 6 with the MWA and UTMOST, respectively. Of the detected pulses, 51 had counterparts at both frequencies and exhibited steep spectral indices for both the bright main pulse component and the precursor component. We find that the bright state pulse energy distribution is best parameterized by a log-normal distribution at both frequencies, contrary to previous results that suggested a power law distribution. Further low-frequency observations are required in order to explore in detail aspects such as pulse-to-pulse variability and intensity modulations, as well as to better constrain the signal propagation effects due to the interstellar medium and intermittency characteristics at these frequencies. The spectral index, extended profile emission covering a large fraction of pulse longitude, and the broadband intermittency of PSR J1107–5907 suggest that future low-frequency pulsar searches—for instance, those planned with SKA-Low—will be in an excellent position to find and investigate new pulsars of this type.
Minimal scenarios for leptogenesis and CP violation

The relation between leptogenesis and CP violation at low energies is analyzed in detail in the framework of the minimal seesaw mechanism. Working, without loss of generality, in a weak basis where both the charged lepton and the right-handed Majorana mass matrices are diagonal and real, we consider a convenient generic parametrization of the Dirac neutrino Yukawa coupling matrix and identify the necessary condition which has to be satisfied in order to establish a direct link between leptogenesis and CP violation at low energies. In the context of the LMA solution of the solar neutrino problem, we present minimal scenarios which allow for the full determination of the cosmological baryon asymmetry and the strength of CP violation in neutrino oscillations. Some specific realizations of these minimal scenarios are considered. The question of the relative sign between the baryon asymmetry and CP violation at low energies is also discussed.
Dual-Space Graph-Based Interaction Network for RGB-Thermal Semantic Segmentation in Electric Power Scene

Real-time scene comprehension is the basis for automatic electric power inspection. However, existing RGB-based scene comprehension methods may achieve unsatisfied performance when dealing with complex scenarios, insufficient illumination or occluded appearances. To solve this problem, by cooperating visual and thermal images, the Dual-Space Graph-based Interaction Network (DSGBINet) is proposed to achieve all-day time semantic segmentation of power equipment in high-voltage power transmission line and electric transformer substation scenes. Specifically, modality-specific features are first extracted via two separate backbone networks with the same architecture. Multi-modality high-level features are first fused via long-range relationship in coordinate space. Then, multi-modality features from regular grids are further clustered and assigned to vertices in feature space. Cross-graph and inner-graph regional relations are utilized for reasoning and enhancement, which could exploit the mutual benefits and extract rich contextual information in a semantic view. Furthermore, to overcome the huge scale difference and the inherent characteristic of thermal images, the idea of multi-task learning is integrated into the decoding process. The edge detection and semantic segmentation are achieved collaboratively, which could segment the different power equipment more accurately and completely. The comparative and ablation experiments on the proposed two RGB-T semantic segmentation datasets evaluate the effectiveness and robustness of the proposed network compared with existing state-of-the-art methods. The extended experiments on the public datasets further demonstrate the superiority of the proposed method. Our dataset and code will be released at: https://github.com/hhujiang/DSGBINet.
The Carina Project - VIII. The α-element abundances

We have performed a new abundance analysis of Carina Red Giant (RG) stars from spectroscopic data collected with UVES (high resolution) and FLAMES/GIRAFFE (high and medium resolution) at ESO/VLT. The former sample includes 44 RGs, while the latter consists of 65 (high) and ~800 (medium resolution) RGs, covering a significant fraction of the galaxy's RG branch (RGB), and red clump stars. To improve the abundance analysis at the faint magnitude limit, the FLAMES/GIRAFFE data were divided into ten surface gravity and effective temperature bins. The spectra of the stars belonging to the same gravity/temperature bin were stacked. This approach allowed us to increase by at least a factor of five the signal-to-noise ratio in the faint limit (V>20.5mag). We took advantage of the new photometry index cU,B,I introduced by Monelli et al. (2014), as an age and probably a metallicity indicator, to split stars along the RGB. These two stellar populations display distinct [Fe/H] and [Mg/H] distributions: their mean Fe abundances are -2.15$\pm$0.06dex (sig=0.28), and -1.75$\pm$0.03dex (sig=0.21), respectively. The two iron distributions differ at the 75% level. This supports preliminary results by Lemasle et al. (2012) and by Monelli et al. (2014). Moreover, we found that the old and intermediate-age stellar populations have mean [Mg/H] abundances of -1.91$\pm$0.05dex (sig=0.22) and -1.35$\pm$0.03dex (sig=0.22); these differ at the 83% level. Carina's {\alpha}-element abundances agree, within 1sigma, with similar abundances for field Halo stars and for cluster (Galactic, Magellanic) stars. The same outcome applies to nearby dwarf spheroidals and ultra-faint dwarf galaxies, in the iron range covered by Carina stars. Finally, we found evidence of a clear correlation between Na and O abundances, thus suggesting that Carina's chemical enrichment history is quite different than in the globular clusters.
Evidence for Asphericity in a Subluminous Type Ia Supernova: Spectropolarimetry of SN 1999by

We present polarization spectra near maximum light for the strongly subluminous Type Ia supernova SN 1999by that show that the supernova is intrinsically polarized. SN 1999by has an observed, overall level of polarization of ≈0.3%-0.8%, a rise of the polarization P redward of 6500 Å, and a change in polarization across the Si II λ6150 feature of about 0.4%. The presentation of the polarization at different wavelengths in the Q-U plane is shown to be a powerful tool to determine the overall geometry and the interstellar component. The distribution of points with wavelength using this empirical Q-U plane method reveals that SN 1999by has a well-defined axis of symmetry and suggests an interstellar polarization (ISP) vector with PISP = 0.3% and position angle Θ = 150° with an error circle in the Q-U plane of radius about 0.1%. Synthetic non-LTE spectra for axisymmetric configurations based on delayed-detonation models have been computed assuming ellipsoidal geometry. The input ejecta structure and composition are based on a Chandrasekhar mass delayed-detonation model. The parameters of the explosion are chosen to reproduce the time evolution of IR spectra of SN 1999by without further adjustments. Spherical models are then mapped onto ellipsoidal geometries and the axis ratio, viewing angle, and ISP adjusted to provide the best agreement with the polarization spectra. Both flux and polarization spectra can be reasonably well reproduced by models with an asphericity of ≈20% observed equator-on. The general properties of the polarization can be understood as a consequence of the structure of subluminous models. Best fits are obtained for the theoretical models with PISP = 0.25% and Θ = 140°, consistent with the empirical method. We discuss our results for this subluminous Type Ia in the context of "normally bright" Type Ia supernovae. For normally bright Type Ia, the photosphere is near the inner iron-rich layers at maximum light and the ubiquitous iron lines give a rapid variation to the model polarization spectra. In subluminous models, the photosphere near maximum is in the silicon layers with fewer lines and a smoother overall polarization spectrum, as observed for SN 1999by. Though data are sparse, the low upper limits for polarization determined for many normal events in contrast to the high polarization in SN 1999by may suggest a relation between the asymmetry we observed and the mechanism that produces a subluminous Type Ia. Among various mechanisms, rapid rotation of the progenitor white dwarf and/or an explosion during a binary white dwarf merger process are likely candidates to explain the asphericity in SN 1999by.
Mass models of the Milky Way

We present a simple method for fitting parametrized mass models of the Milky Way to observational constraints. We take a Bayesian approach which allows us to take into account input from photometric and kinematic data, and expectations from theoretical modelling. This provides us with a best-fitting model, which is a suitable starting point for dynamical modelling. We also determine a probability density function on the properties of the model, which demonstrates that the mass distribution of the Galaxy remains very uncertain. For our choices of parametrization and constraints, we find disc scalelengths of 3.00 ± 0.22 and 3.29 ± 0.56 kpc for the thin and thick discs, respectively, a solar radius of 8.29 ± 0.16 kpc and a circular speed at the Sun of 239 ± 5 km s−1, a total stellar mass of 6.43 ± 0.63 × 1010 M⊙, a virial mass of 1.26 ± 0.24 × 1012 M⊙ and a local dark matter density of 0.40 ± 0.04 GeV cm−3. We find some correlations between the best-fitting parameters of our models (for example, between the disc scalelengths and the solar radius), which we discuss. The chosen disc scaleheights are shown to have little effect on the key properties of the model.
Radio and X-ray observations of PSR B0540¿69

PSR B0540−69 is one of a small handful of pulsars known to emit giant pulses and the only extra-galactic pulsar known to do so. We observed the pulsar for a total of 72 h over a 6 month interval and detected 141 giant pulses. We have obtained correct phasing between the radio arrival times of the giant pulses and the X-ray pulse profile. The giant pulses occur in two phase windows, located 6.7 ms before and 5.0 ms after the mid-point of the X-ray profile. We have detected the integrated profile of the pulsar at 1.4 GHz with a flux density of only 24 µJy. The statistics of the giant pulses are clearly power law and it is likely that the giant pulses contribute only a few per cent of the integrated pulse flux density, similar to other pulsars with giant pulse emission. Simultaneous X-ray and radio observations show no significant increase in the X-ray flux at the time of the radio giants. The relative enhancements in the X-ray emission must be at least 5.5 times smaller than in the radio emission. Ke yw ords: pulsars: individual: PSR B0540−69.
Temperature evolution of spin dynamics in two- and three-dimensional Kitaev models: Influence of fluctuating Z 2 flux

The long-sought quantum spin liquid is a quantum-entangled magnetic state leading to the fractionalization of spin degrees of freedom. Quasiparticles emergent from the fractionalization affect not only the ground-state properties but also thermodynamic behavior in a peculiar manner. Here we investigate how the spin dynamics evolves from the high-temperature paramagnet to the quantum spin-liquid ground state, for the Kitaev spin model describing the fractionalization into itinerant matter fermions and localized ${Z}_{2}$ fluxes. Beyond the previous studies [J. Yoshitake, J. Nasu, and Y. Motome, Phys. Rev. Lett. 117, 157203 (2016); J. Yoshitake, J. Nasu, Y. Kato, and Y. Motome, Phys. Rev. B 96, 024438 (2017)], in which the mean-field nature of the cluster dynamical mean-field theory prevented us from studying low-temperature properties, we develop a numerical technique by applying the continuous-time quantum Monte Carlo (CTQMC) method to statistical samples generated by the quantum Monte Carlo (QMC) method in a Majorana fermion representation. This QMC+CTQMC method is fully unbiased and enables us to investigate the low-temperature spin dynamics dominated by thermally excited ${Z}_{2}$ fluxes, including the unconventional phase transition caused by ${Z}_{2}$ flux loops in three dimensions, which was unreachable by the previous methods. We apply this technique to the Kitaev model in both two and three dimensions. Our results clearly distinguish two cases: while the dynamics changes smoothly through the crossover in the two-dimensional honeycomb case, it exhibits singular behaviors at the phase transition in the three-dimensional hyperhoneycomb case. We show that the low-temperature spin dynamics is a sensitive probe for thermally fluctuating ${Z}_{2}$ fluxes that behave very differently between two and three dimensions.
A Single Differential Equation Description of Membrane Properties Underlying the Action Potential and the Axon Electric Field

Abstract In a succession of articles published over 65 years ago, Sir Alan Lloyd Hodgkin and Sir Andrew Fielding Huxley established what now forms our physical understanding of excitation in nerve, and how the axon conducts the action potential. They uniquely quantified the movement of ions in the nerve cell during the action potential, and demonstrated that the action potential is the result of a depolarizing event across the cell membrane. They confirmed that a complete depolarization event is followed by an abrupt increase in voltage that propagates longitudinally along the axon, accompanied by considerable increases in membrane conductance. In an elegant theoretical framework, they rigorously described fundamental properties of the Na+ and K+ conductances intrinsic to the action potential. Notwithstanding the elegance of Hodgkin and Huxley’s incisive and explicative series of discoveries, their model is mathematically complex, relies on no small number of stochastic factors, and has no analytical solution. Solving for the membrane action potential and the ionic currents requires integrations approximated using numerical methods. In this article I present an analytical formalism of the nerve action potential, Vm and that of the accompanying cell membrane electric field, Em. To conclude, I present a novel description of Vm in terms of a single, nonlinear differential equation. This is an original stand-alone article: the major contribution is the latter, and how this description coincides with the cell membrane electric field. This work has necessitated unifying information from two preceding papers [1,2], each being concerned with the development of closed-form descriptions of the nerve action potential, Vm.
Correcting Postural Deviations: An Evidence- Supported Shift in Paradigm

Somatic syndromes of the spinal region may develop secondary to postural dysfunction. Traditionally, emphasis has been placed on correcting postural asymmetries by attempting to change muscle-tendon unit length. The effectiveness of this approach in providing prolonged muscle-tendon unit length changes and optimal postural outcomes has met with controversy. The time has come for a redirection of goals in conservative care for postural dysfunction of the spinal regions. An emphasis needs to be placed on continuous, self-awareness training of postural correction that will facilitate lasting neuromuscular adaptations. The purpose of this review is to rationalize the need to veer from exercises attempting to adjust the muscle-tendon unit length and recognize the evidence-supported impact of simple self-correction strategies meant to facilitate neuromuscular adjustments and correct postural asymmetries.
Difficulties Distinguishing Dark Energy from Modified Gravity via Redshift Distortions

The bulk motion of galaxies induced by the growth of cosmic structure offers a rare opportunity to test the validity of general relativity across cosmological scales. However, modified gravity can be degenerate in its effect with the unknown values of cosmological parameters. More seriously, even the 'observed' value of the redshift-space distortions used to measure the fluctuation growth rate depends on the assumed cosmological parameters (the Alcock-Paczynski effect). We give a full analysis of these issues, showing how to combine redshift-space distortions with baryon acoustic oscillations and CMB data, in order to obtain joint constraints on deviations from general relativity and on the equation of state of dark energy while allowing for factors such as nonzero curvature. In particular we note that the evolution of {Omega}{sub m}(z), along with the Alcock-Paczynski effect, produces a degeneracy between the equation of state w and the modified growth parameter {gamma}. Typically, the total marginalized error on either of these parameters will be larger by a factor {approx_equal}2 compared to the conditional error where one or the other is held fixed. We argue that future missions should be judged by their figure of merit as defined in the w{sub p}-{gamma} plane, and note thatmore » the inclusion of spatial curvature can degrade this value by an order of magnitude. « less
Selective measurement of charge dynamics in an ensemble of nitrogen-vacancy centers in nanodiamond and bulk diamond

Nitrogen-vacancy (NV) centers in diamond have attracted considerable interest in sensing of weak magnetic fields, such as those created by biological systems. Detecting such feeble signals requires near-surface NV centers, to reduce the distance between NVs and sources. Moreover, dense ensembles of NVs are highly desirable to reduce measurement time. However, robust charge state switching is often observed in these systems, resulting in a complex interplay between charge and spin dynamics that can reduce the attainable level of spin polarization, and consequently, sensitivity. Understanding the mechanisms behind charge state switching is, therefore, crucial to developing NV based sensors. Here, we demonstrate a novel method to selectively measure charge dynamics in an ensemble of NVs by quenching the spin polarization using an off-axis magnetic field. Utilizing this technique, we show that, in nanodiamonds, charge state instability increases with increasing NV density. In the case of bulk single crystal diamond, we show that NV centers located near the surface are more stable in the neutral (NV$^{0}$) charge state, while the negatively charged (NV$^{-}$) form is more stable in bulk.