Table of contents

We present the evolution of the mass–metallicity (MZ) relation at z = 4–10 derived with 135 galaxies identified in JWST/NIRSpec data taken from the three major public spectroscopy programs of ERO, GLASS, and CEERS. Because there are many discrepancies between the flux measurements reported by the early ERO studies, we first establish our NIRSpec data reduction procedure for reliable emission-line flux measurements and errors, successfully explaining Balmer decrements with no statistical tensions thorough comparisons with the early ERO studies. Applying the reduction procedure to the 135 galaxies, we obtain emission-line fluxes for physical property measurements. We confirm that 10 out of the 135 galaxies with [O iii] λ4363 lines have electron temperatures of ≃(1.1–2.3) × 10⁴ K, similar to lower-z star-forming galaxies, which can be explained by heating by young massive stars. We derive the metallicities of the 10 galaxies by a direct method and the rest of the galaxies with strong lines using the metallicity calibrations of Nakajima et al. applicable for these low-mass metal-poor galaxies, anchoring the metallicities with the direct-method measurements. We thus obtain the MZ relation and star formation rate (SFR)–MZ relation over z = 4–10. We find that there is a small evolution of the MZ relation from z ∼ 2–3 to z = 4–10, while interestingly the SFR–MZ relation shows no evolution up to z ∼ 8 but a significant decrease at z > 8 beyond the errors This SFR–MZ relation decrease at z > 8 may suggest a break of the metallicity equilibrium state via star formation, inflow, and outflow, while further statistical and local-baseline studies are needed for a conclusion.

We develop a new model for automatic extraction of reported measurement values from the astrophysical literature, utilizing modern natural language processing techniques. We use this model to extract measurements present in the abstracts of the approximately 248,000 astrophysics articles from the arXiv repository, yielding a database containing over 231,000 astrophysical numerical measurements. Furthermore, we present an online interface (Numerical Atlas) to allow users to query and explore this database, based on parameter names and symbolic representations, and download the resulting data sets for their own research uses. To illustrate potential use cases, we then collect values for nine different cosmological parameters using this tool. From these results, we can clearly observe the historical trends in the reported values of these quantities over the past two decades and see the impacts of landmark publications on our understanding of cosmology.

Inspired by the conundrum of the gravitational event GW190814, which brings to light the coalescence of a 23 M_⊙ black hole with a yet-to-be-determined secondary component, we look to modeling compact objects within the framework of $f({ \mathcal Q })$ gravity by employing the method of gravitational decoupling. We impose a quadratic equation of state (EOS) for the interior matter distribution, which in the appropriate limit reduces to the MIT bag model. The governing field equations arising from gravitational decoupling bifurcate into the $\rho ={\theta }_{0}^{0}$ and ${p}_{r}={\theta }_{1}^{1}$ sectors, leading to two distinct classes of solutions. Both families of solutions are subjected to rigorous tests, qualifying them to describe a plethora of compact objects, including neutron stars, strange stars, and the possible progenitor of the secondary component of GW190814. Using observational data of mass–radius relations for compact objects LMC X-4, Cen X-3, PSR J1614–2230, and PSR J0740+6620, we show that it is possible to generate stellar masses and radii beyond 2.0 M_⊙ for neutron stars. Our findings reveal that the most suitable and versatile model in this framework is the quadratic EOS, which accounts for a range of low-mass stars and typical stellar candidates describing the secondary component of GW190814.

Using high-resolution spectra of Ni ii recorded using Fourier transform (FT) spectroscopy of continuous, nickel–helium hollow cathode discharge sources in the region 143–5555 nm (1800–70,000 cm⁻¹, the analysis of 1016 Ni ii lines confirmed and optimized 206 previously reported energy levels of the (³F) parent term, from 3d⁸(³F)5f to 3d⁸(³F)9s, lying between 122,060 and 138,563 cm⁻¹. The uncertainties of these levels have been improved by at least an order of magnitude compared with their previously reported values. With the increased resolution and spectral range of the FT measurements, compared to previously published grating spectra, we were able to extend our analysis to identify and establish 33 new energy levels of Ni ii, which are reported here for the first time. Eigenvector compositions of all revised and newly established energy levels were calculated using the orthogonal operator method. In addition, an improved ionization energy of 146,541.35 ± 0.15 cm⁻¹ for Ni ii, using highly excited levels of the 3d⁸(³F)5g, 3d⁸(³F)6g, and 3d⁸(³F)6h configurations, has been derived.

In this work, we combined AWSoM's nonequilibrium ionization (NEI) calculations from Szente et al. with the synthetic spectral computations of SPECTRUM to predict nonequilibrium line intensities across the entire domain of the AWSoM 3D global model. We find that the resulting spectra are strongly affected by nonequilibrium effects in the fast-wind regions and streamer edges and that these effects propagate to narrowband images from SoHO/EIT, SECCHI/EUVI, and SDO/AIA. The dependence shows a different nature for each line observed, resulting in significant changes in line intensity, which need to be accounted for during plasma diagnostics. However, we also find that these effects depend on the local plasma properties, and that no single correction can be developed to account for nonequilibrium effects in observed spectra and images. With a comparison to observational data, we saw that the changes due to NEI, while significant, are not sufficient to account for the differences between Hinode/EIS spectra and AWSoM/SPECTRUM predictions.

Gas infall motions play a crucial role in high-mass star formation and are characterized by observable signatures of blueshifted asymmetric spectral line profiles ("blue profiles"). However, the connection between blue profiles and infall motions is unclear due to complex gas motions at parsec scales. In this study, we present the results of an HCN (4–3) mapping survey conducted with the James Clerk Maxwell Telescope, toward 38 massive clumps exhibiting blue profiles in HCO⁺ (3–2). We extract 34 HCN cores from the 38 observed fields. The core-averaged spectra show various line profiles, indicating that blue-profile HCO⁺ (3–2) does not guarantee the same in HCN (4–3). Through non-LTE radiative-transfer calculations, we attribute the low detection rate of high-J blue profiles to a combination of insufficient HCN (4–3) opacity and the intricate gas motion across different density layers. A comparison between the MALT90 and Bolocam Galactic Plane Survey line surveys highlights the importance of appropriate tracers, high spectral resolution, and column density thresholds when searching for blue profiles. We select 11 reliable infall candidates and adopt the Hill5 model to fit the infall velocity of 0.2–1.6 km s⁻¹, corresponding to 5%–74% of freefall velocity. Assuming a spherically collapsing model, we estimate the median and mean mass infall rates to be 4.5 × 10⁻³ and 7.6 × 10⁻³M_⊙ yr⁻¹, respectively. The consistency of the mass infall rates among different transitions suggests a steady accretion process from the clump gas envelope to the inner region.

The forthcoming Chinese Space Station Telescope (CSST) wide-field multiband imaging survey will produce seven-band photometric spectral energy distributions (SEDs) for billions of galaxies. The effective extraction of astronomical information from these massive data sets of SEDs relies on the techniques of SED synthesis (or modeling) and SED analysis (or fitting). We evaluate the performance of the latest version of the BayeSED code combined with SED models with increasing complexity for simultaneously determining the photometric redshifts and stellar population parameters of galaxies in this survey. By using an empirical statistics–based mock galaxy sample without SED modeling errors, we show that the random observational errors in photometries are more important sources of errors than the parameter degeneracies and Bayesian analysis method and tool. By using a Horizon-AGN hydrodynamical simulation–based mock galaxy sample with SED modeling errors about the star formation histories (SFHs) and dust attenuation laws (DALs), the simple typical assumptions lead to significantly worse parameter estimation with CSST photometries only. SED models with more flexible (or complicated) forms of SFH/DAL do not necessarily lead to better estimation of redshift and stellar population parameters. We discuss the selection of the best SED model by means of Bayesian model comparison in different surveys. Our results reveal that Bayesian model comparison with Bayesian evidence may favor SED models with different complexities when using photometries from different surveys. Meanwhile, the SED model with the largest Bayesian evidence tends to give the best performance of parameter estimation, which is clearer for photometries with higher discriminative power.

The progenitors for many types of supernovae (SNe) are still unknown, and an approach to diagnose their physical origins is to investigate the light-curve brightness and shape of a large set of SNe. However, it is often difficult to compare and contrast the existing sample studies due to differences in their approaches and assumptions, for example, in how to eliminate host galaxy extinction, and this might lead to systematic errors when comparing the results. We therefore introduce the Hybrid Analytic Flux FittEr for Transients (HAFFET), a Python-based software package that can be applied to download photometric and spectroscopic data for transients from open online sources, derive bolometric light curves, and fit them to semianalytical models for estimation of their physical parameters. In a companion study, we have investigated a large collection of SNe Ib and Ic observed with the Zwicky Transient Facility (ZTF) with HAFFET, and here we detail the methodology and the software package to encourage more users. As large-scale surveys such as ZTF and LSST continue to discover increasing numbers of transients, tools such as HAFFET will be critical for enabling rapid comparison of models against data in statistically consistent, comparable, and reproducible ways. Additionally, HAFFET is created with a graphical user interface mode, which we hope will boost the efficiency and make the usage much easier (https://github.com/saberyoung/HAFFET).

The LAMOST Low-Resolution Spectroscopic (LAMOST-LRS) Survey provides radial velocities of 10 million stars. These observations can be used to identify new single-lined spectroscopic binaries (SB1s) with their preliminary spectroscopic orbits. First, we perform a statistical χ² test on a subsample of LAMOST-LRS stars with velocity observations sufficient for the present work to obtain a set of 6852 radial velocity variables. Subsequently, we discard 399 astrophysical variables through crossmatching with variable catalogs, resulting in 1297 SB1 candidates. Finally, in order to reliably identify SB1s among these SB1 candidates, we employ a combination of The joker, rvfit, and Levenberg–Marquardt algorithms to give the best-fit solutions. An SB1 is identified if its orbital solution satisfies the criteria of the goodness-of-fit statistic (F2) < 3.1, the signal significance > 10, and the maximum gap in phase (phase_gap_max) < 0.3. Our final catalog of SB1s contains 255 systems, 168 of which are newly discovered ones. Cross validation results indicate that the determined orbital periods are consistent with periods of external catalogs within 1σ uncertainties. The period–eccentricity diagram illustrates that a majority of short-period binaries have small eccentricities. Furthermore, in comparison to the general sample, the SB1 catalog exhibits a relatively higher ratio of dwarfs than giants and a slightly lower metallicity.

M87 has been monitored with a cadence of 5 days over a span of 9 months through the near-ultraviolet (NUV; F275W) and optical (F606W) filters of the Wide Field Camera 3 (WFC3) of the Hubble Space Telescope. This unprecedented dataset yields the NUV and optical light and color curves of 94 M87 novae, characterizing the outburst and decline properties of the largest extragalactic nova dataset in the literature (after M31 and M81). We test and confirm nova modelers' prediction that recurrent novae cannot erupt more frequently than once every 45 days, show that there are zero rapidly recurring novae in the central ∼1/3 of M87 with recurrence times <130 days, demonstrate that novae closely follow the K-band light of M87 to within a few arcsecs of the galaxy nucleus, show that nova NUV light curves are as heterogeneous as their optical counterparts, and usually peak 5–30 days after visible light maximum, determine our observations' annual detection completeness to be 71%–77%, and measure the rate R_nova of nova eruptions in M87 as ${352}_{-37}^{+37}$ yr⁻¹. The corresponding luminosity-specific classical nova rate for this galaxy is ${7.91}_{-1.20}^{+1.20}/\mathrm{yr}/{10}^{10}\,{L}_{\odot }{,}_{{\rm{K}}}$. These rates confirm that ground-based observations of extragalactic novae miss most faint, fast novae and those near the centers of galaxies. An annual M87 nova rate of 300 or more seems inescapable. A luminosity-specific nova rate of ∼7–10/yr/10¹⁰L_⊙,_K in all types of galaxies is indicated by the data available in 2023.

With its unprecedented sensitivity and spatial resolution, the James Webb Space Telescope (JWST) has opened a new window for time-domain discoveries in the infrared. Here we report observations in the only field that has received four epochs (spanning 126 days) of JWST NIRCam observations in Cycle 1. This field is toward MACS J0416.1−2403, which is a rich galaxy cluster at redshift z = 0.4 and is one of the Hubble Frontier Fields. We have discovered 14 transients from these data. Twelve of these transients happened in three galaxies (with z = 0.94, 1.01, and 2.091) crossing a lensing caustic of the cluster, and these transients are highly magnified by gravitational lensing. These 12 transients are likely of a similar nature to those previously reported based on the Hubble Space Telescope (HST) data in this field, i.e., individual stars in the highly magnified arcs. However, these 12 could not have been found by HST because they were too red and too faint. The other two transients are associated with background galaxies (z = 2.205 and 0.7093) that are only moderately magnified, and they are likely supernovae. They indicate a demagnified supernova surface density, when monitored at a time cadence of a few months to a ∼3–4 μm survey limit of AB ∼28.5 mag, of ∼0.5 arcmin⁻² integrated to z ≈ 2. This survey depth is beyond the capability of HST but can be easily reached by JWST.

Observational studies of the Earth's radiation belts indicate that Alfvénic fluctuations in the frequency range of 2–25 mHz accelerate electrons to relativistic energies. For decades, statistical models of radiation belts have quantified the impact of Alfvénic waves in terms of quasi-linear diffusion. However, quasi-linear models are inadequate to quantify Alfvénic radial transport occurring on timescales comparable to the azimuthal drift period of 0.1–10 MeV electrons. With recent advances in observational methodologies offering coverage of the Earth's radiation belts on fast timescales, a theoretical framework that distinguishes between fast and diffusive radial transport can be tested for the first time in situ. In this report, we present a drift-kinetic description of radial transport for planetary radiation belts. We characterize fast linear processes and determine the conditions under which higher-order effects become dynamically significant. In the linear regime, wave–particle interactions are categorized in terms of resonant and nonresonant responses. We demonstrate that the phenomenon of zebra stripes is nonresonant and can originate from injection events in the inner radiation belts. We derive a radial diffusion coefficient for a field model that satisfies Faraday's law and that contains two terms: one scaling as L¹⁰ independent of the azimuthal number m, and a second scaling as m²L⁶. In the higher-order regime, azimuthally symmetric waves with properties consistent with in situ measurements can energize 10–100 keV electrons in less than a drift period. This process provides new evidence that acceleration by Alfvénic waves in radiation belts cannot be fully contained within diffusive models.

The KAPPA package is designed for calculations of optically thin spectra for the non-Maxwellian κ-distributions. This paper presents an extension of the database to allow calculations of the spectra for extreme values of κ < 2, which are important for accurate diagnostics of the κ-distributions in the outer solar atmosphere. In addition, two improvements were made to the ionization equilibrium calculations within the database. First, the ionization equilibrium calculations now include the effects of electron impact multi-ionization (EIMI). Although relatively unimportant for Maxwellian distribution, EIMI becomes important for some elements, such as Fe and low values of κ, where it modifies the ionization equilibrium significantly. Second, the KAPPA database now includes the suppression of dielectronic recombination at high electron densities, evaluated via the suppression factors. We find that at the same temperature, the suppression of dielectronic recombination is almost independent of κ. The ionization equilibrium calculations for the κ-distributions are now provided for a range of electron densities.

We present a 0.3–4.5 μm 16-band photometric catalog for the Spitzer/HETDEX Exploratory Large-Area (SHELA) survey. SHELA covers an ∼27 deg² field within the footprint of the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX). Here we present new DECam imaging and an rizK_s band–selected catalog of four million sources extracted using a fully model-based approach. We validate our photometry by comparing with the model-based DECam Legacy Survey. We analyze the differences between model-based and aperture photometry by comparing with the previous SHELA catalog, finding that our model-based photometry can measure point sources to fainter fluxes and better capture the full emission of resolved sources. The catalog is 80% (50%) complete at riz ∼ 24.7 (25.1) AB mag, and the optical photometry reaches a 5σ depth of ∼25.5 AB mag. We measure photometric redshifts and achieve a 1σ scatter of Δz/(1 + z) of 0.04 with available spectroscopic redshifts at 0 ≤ z ≤ 1. This large-area, multiwavelength photometric catalog, combined with spectroscopic information from HETDEX, will enable a wide range of extragalactic science investigations.

We investigate the material properties of a mixture of hydrogen, helium, and oxygen representative of Saturn's interior at pressure–temperature conditions of a recent Saturn model (see Mankovich & Fortney) with molecular dynamics simulations based on density functional theory. Their model considers the demixing of hydrogen and helium and predicts a He-rich layer above a diluted core. We calculate the thermodynamic and transport properties and discuss the impact on Saturn's evolution and interior structure. We find a significant impact of the He-rich layer on the specific heat capacity, speed of sound, viscosity, diffusion coefficients, thermal and electrical conductivity, Lorenz number, and magnetic and thermal diffusivities.

The photodissociation of O₂ is thought to play a vital role in blocking UV radiation in the Earth's atmosphere and likely has great importance in characterizing exoplanetary atmospheres. This work considers four photodissociation processes of O₂ associated with its four electronic states, whose potential energy curves and transition dipole moments are calculated at the icMRCI+Q/aug-cc-pwCV5Z-DK level of theory. The quantum-mechanical approach is used to compute the state-resolved cross sections for two triplet transitions from the ground X ${}^{3}{{\rm{\Sigma }}}_{{\rm{g}}}^{-}$ state to the excited B ${}^{3}{{\rm{\Sigma }}}_{{\rm{u}}}^{-}$ and E ${}^{3}{{\rm{\Sigma }}}_{{\rm{u}}}^{-}$ states, and for two singlet transitions from the a ¹Δ_g and b ${}^{1}{{\rm{\Sigma }}}_{{\rm{g}}}^{+}$ states to the 1 ¹Π_u state, with a consideration of photon wavelengths from 500 Å to the relevant threshold. Assuming the populations of the initial states satisfy a Boltzmann distribution, the temperature-dependent photodissociation cross sections are estimated at gas dynamic temperatures of 0–10,000 K, in which the discrete progressions of the B ${}^{3}{{\rm{\Sigma }}}_{{\rm{u}}}^{-}\leftarrow {\rm{X}}$${}^{3}{{\rm{\Sigma }}}_{{\rm{g}}}^{-}$ and E ${}^{3}{{\rm{\Sigma }}}_{{\rm{u}}}^{-}\leftarrow {\rm{X}}$${}^{3}{{\rm{\Sigma }}}_{{\rm{g}}}^{-}$ transitions are also considered. The photodissociation rates of O₂ in the interstellar, solar, and blackbody radiation fields are also calculated using the temperature-dependent cross sections. The resulting photodissociation cross sections and rates are important for the atmospheric chemistry of Earth and may be also useful for the atmospheric exploration of exoplanets.

The Swift Deep Galactic Plane Survey (DGPS) is a Swift Key Project consisting of 380 tiled pointings covering ∼40 deg² of the Galactic plane between longitude 10 < ∣l∣ < 30 deg and latitude ∣b∣ < 0.5 deg. Each pointing has a 5 ks exposure, yielding a total of 1.9 Ms spread across the entire survey footprint. Phase I observations were carried out between 2017 March and 2021 May. The survey is complete to depth L_X > 10³⁴ erg s⁻¹ to the edge of the Galaxy. The main survey goal is to produce a rich sample of new X-ray sources and transients, while also covering a broad discovery space. Here, we introduce the survey strategy and present a catalog of sources detected during Phase I observations. In total, we identify 928 X-ray sources, of which 348 are unique to our X-ray catalog. We report on the characteristics of sources in our catalog and highlight sources newly classified and published by the DGPS team.

Regular, automated testing is a foundational principle of modern software development. Numerous widely used continuous integration systems exist, but they are often not suitable for the unique needs of scientific simulation software. Here we describe the testing infrastructure developed for and used by the Modules for Experiments in Stellar Astrophysics (MESA) project. This system allows the computationally demanding MESA test suite to be regularly run on a heterogeneous set of computers and aggregates and displays the testing results in a form that allows for the rapid identification and diagnosis of regressions. Regularly collecting comprehensive testing data also enables longitudinal studies of the performance of the software and the properties of the models it generates.

Real-time detection of solar radio bursts is crucial in solar physics research and space weather forecasting. However, current research on the automatic detection of solar radio bursts is limited to identifying the presence or absence of solar radio bursts or recognizing only a single type of burst, such as type II or III. Furthermore, existing methods cannot learn spectral and temporal features and often suffer from the drawbacks of large network models, resulting in slow speeds. This paper proposes an automatic recognition and localization method based on a lightweight object detection model for solar radio burst events. We collected observation data from e-CALLISTO and established a data set containing type II, III, IV, and V solar radio bursts. To address the real-time requirements of practical applications and consider the temporal and frequency domain information of spectrogram images, we improved a vision transformer with a self-attention mechanism and adopted a lightweight model for detection. The experimental results demonstrate that our proposed method achieves an average precision at a 50% intersection-over-union threshold of 78.2% and a recall rate of 92% on the established solar radio burst data set. Additionally, the model operates at a detection speed of 54.8 frames s^–1, where a frame refers to a spectral image with a duration of 15 minutes, enabling efficient automated detection and localization of type II, III, IV, and V solar radio bursts.

Analysis of 8,804,545 electron velocity distribution functions, observed by the Wind spacecraft near 1 au between 2005 January 1 and 2022 January 1, was performed to determine the spacecraft floating potential, ϕ_sc. Wind was designed to be electrostatically clean, which helps keep the magnitude of ϕ_sc small (i.e., ∼5–9 eV for nearly all intervals) and the potential distribution more uniform. We observed spectral enhancements of ϕ_sc at frequencies corresponding to the inverse synodic Carrington rotation period with at least three harmonics. The two-dimensional histogram of ϕ_sc versus time also shows at least two strong peaks, with a potential third, much weaker peak. These peaks vary in time, with the intensity correlated with solar maximum. Thus, the spectral peaks and histogram peaks are likely due to macroscopic phenomena like coronal mass ejections (solar cycle dependence) and stream interaction regions (Carrington rotation dependence). The values of ϕ_sc are summarized herein and the resulting data set is discussed.

Angelo Secchi, an Italian Jesuit and prominent scientist of the 19th century, and one of the founders of modern astrophysics, observed the Sun regularly at the Collegio Romano in Rome, Italy, for more than 25 yr. Results from his observations are reported in articles published in the scientific journals of the time, as well as in drawings and personal notebooks that are stored in the historical archive of the Istituto Nazionale di Astrofisica Osservatorio Astronomico di Roma. The latter material, which reports solar observations performed from 1853–1878, includes original documents from Secchi and from a few of his close collaborators. The above unique material has recently been digitized for preservation purposes and for allowing the scientific exploitation of data not easily accessible so far. A total of more than 5400 digital images have been produced. Here we present the archival material and the new digital data derived from it. We also present results obtained from our primary analysis of the new digital data. In particular, we produced new measurements of the group number from 1853–1878, which will be available for future recalibration of the group number series.

It is well accepted that the physical properties obtained from the solar magnetic field observations of active regions (ARs) are related to solar eruptions. These properties consist of temporal features that might reflect the evolution process of ARs, and spatial features that might reflect the graphic properties of ARs. In this study, we generated video data sets with timescales of 1 day and image data sets of the SHARP radial magnetic field of the ARs from 2010 May to 2020 December. For the ARs that evolved from "quiet" to "active" and erupted the first strong flares in 4 days, we extract and investigate both the temporal and spatial features of ARs from videos, aiming to capture the evolution properties of their magnetic field structures during their transition process from "quiet" (non–strong flaring) to "active" (strong flaring). We then conduct a comparative analysis of the model performance by video input and single-image input, as well as of the effect of the model performance variation with the prediction window up to 3 days. We find that for those ARs that erupted the first strong flares in 4 days, the temporal features that reflect their evolution from "quiet" to "active" before the first strong flares can be recognized and extracted from the video data sets by our network. These features turn out to be important predictors that can effectively improve strong-flare prediction, especially by reducing the false alarms in a nearly 2 day prediction window.

We present the combination of ALMA-IMF and single-dish continuum images from the MUSTANG-2 Galactic Plane Survey (MGPS90) at 3 mm and the Bolocam Galactic Plane Survey (BGPS) at 1 mm. Six and 10 out of the 15 ALMA-IMF fields are combined with MGPS90 and BGPS, respectively. The combination is made via the feathering technique. We used the dendrogram algorithm throughout the combined images, and performed further analysis in the six fields with the combination in both bands (G012.80, W43-MM1, W43-MM2, W43-MM3, W51-E, W51-IRS2). In these fields, we calculated spectral index maps and used them to separate regions dominated by dust or free–free emission, and then performed further structural analysis. We report the basic physical parameters of the dust-dominated (column densities, masses) and ionized (emission measures, hydrogen ionization photon rates) structures. We also searched for multiscale relations in the dust-dominated structures across the analyzed fields, finding that the fraction of mass in dendrogram leaves (which we label leaf mass efficiency (LME)) as a function of molecular gas column density follows a similar trend: a rapid, exponential-like growth, with maximum values approaching 100% in most cases. The observed behavior of the LME with the gas column is tentatively interpreted as an indicator of large star formation activity within the ALMA-IMF protoclusters. W51-E and G012.80 stand out as cases with comparatively large and reduced potential for further star formation, respectively.

We report on a comprehensive multiwavelength study of the pulsars in the globular cluster (GC) M5, including the discovery of M5G, a new compact noneclipsing "black widow" pulsar. Thanks to the analysis of 34 yr of radio data taken with the Five-hundred-meter Aperture Spherical radio Telescope and Arecibo telescopes, we obtained new phase-connected timing solutions for four pulsars and improved those of the other three. These have resulted in, among other things, (a) much improved proper motions for five pulsars, with transverse velocities (relative to the cluster) that are smaller than their respective escape velocities; (b) 3σ and 1.5σ detections of Shapiro delays in M5F and M5D, respectively; and (c) greatly improved measurement of the periastron advance in M5B, whose value of $\dot{\omega }=0\buildrel{\circ}\over{.} 01361(6)$ implies that M5B is still likely to be a heavy (${m}_{p}={1.981}_{-0.088}^{+0.038}\,{M}_{\odot }$) neutron star. The binary pulsars M5D, M5E, and M5F are confirmed to be in low-eccentricity binary systems, the low-mass companions of which are newly identified to be He white dwarfs using Hubble Space Telescope data. Four pulsars are also found to be associated with X-ray sources. Similarly to the eclipsing pulsar M5C, M5G shows little or no nonthermal X-ray emission, indicative of weak synchrotron radiation produced by intrabinary shocks. All seven pulsars known in M5 have short spin periods (<8 ms), and five are in binary systems with low orbital eccentricities. These characteristics differ from the overall GC pulsar population but confirm the expectations for the pulsar population in a cluster with a small rate of stellar encounters per binary system.

The Tianwen-1 (TW1) Mars probe experienced solar conjunction for the first time in 2021. The China VLBI Network (CVN) observes the differential one-way ranging (DOR) signals of TW1 throughout its phase. This paper explores the application of CVN observation data to study the solar wind plasma. First, the frequency and phase of the DOR carrier and sidetones at each station are calculated using the Doppler method. Then, the variations in both the differential phase delays (DPD) and the total electron content (TEC) are calculated using the phase of the sidetones. We also statistically analyze the fluctuations in the Delta-DOR (ΔDOR) group delay. The results indicate that the fluctuations of the frequency, phase, ΔDOR group delay, delay rate, and TEC variations of the TW1 signals increase with the decrease of the heliocentric distance. On 2021 November 2, a coronal mass ejection (CME) passed across the ray paths of the telescope beams, when the heliocentric distance and heliographic latitude of the projected position of Mars were 30.6 Rs and 3°, respectively. Our data catch the impact of the CME on the DOR signals. The change of the DPD reaches 170 ps, which is equivalent to 986 TECU. We utilize the cross correlation to analyze the frequency fluctuations at multiple stations, and obtain the propagation direction and velocity variations of the CME. Our analysis indicates that multifrequency DOR signals observed by very long baseline interferometry stations have great application to characterize the electron density variations and propagation of the solar wind plasma.

We employ the corrected Gaia Early Data Release 3 photometric data and spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) DR7 to assemble a sample of approximately 0.25 million FGK dwarf photometric standard stars for the 12 J-PLUS filters using the stellar color regression (SCR) method. We then independently validate the J-PLUS DR3 photometry and uncover significant systematic errors: up to 15 mmag in the results from the stellar locus method and up to 10 mmag primarily caused by magnitude-, color-, and extinction-dependent errors of the Gaia XP spectra as revealed by the Gaia BP/RP (XP) synthetic photometry (XPSP) method. We have also further developed the XPSP method using the corrected Gaia XP spectra by B. Huang et al. and applied it to the J-PLUS DR3 photometry. This resulted in an agreement of 1–5 mmag with the SCR method and a twofold improvement in the J-PLUS zero-point precision. Finally, the zero-point calibration for around 91% of the tiles within the LAMOST observation footprint is determined through the SCR method, with the remaining approximately 9% of the tiles outside this footprint relying on the improved XPSP method. The recalibrated J-PLUS DR3 photometric data establish a solid data foundation for conducting research that depends on high-precision photometric calibration.

Low-surface-brightness galaxies (LSBGs), fainter members of the galaxy population, are thought to be numerous. However, due to their low surface brightness, the search for a wide-area sample of LSBGs is difficult, which in turn limits our ability to fully understand the formation and evolution of galaxies as well as galaxy relationships. Edge-on LSBGs, due to their unique orientation, offer an excellent opportunity to study galaxy structure and galaxy components. In this work, we utilize the You Only Look Once object detection algorithm to construct an edge-on LSBG detection model by training on 281 edge-on LSBGs in Sloan Digital Sky Survey (SDSS) gri-band composite images. This model achieved a recall of 94.64% and a purity of 95.38% on the test set. We searched across 938,046 gri-band images from SDSS Data Release 16 and found 52,293 candidate LSBGs. To enhance the purity of the candidate LSBGs and reduce contamination, we employed the Deep Support Vector Data Description algorithm to identify anomalies within the candidate samples. Ultimately, we compiled a catalog containing 40,759 edge-on LSBG candidates. This sample has similar characteristics to the training data set, mainly composed of blue edge-on LSBG candidates. The catalog is available online at https://github.com/worldoutside/Edge-on_LSBG.

BL Lacertae is a key monitoring target of the 1.26 m National Astronomical Observatory–Guangzhou University Infrared/Optical telescope. Within the monitored duration from 2020 September 4 to 2022 September 28, we report 13,948 observations at the g, r, and i bands (g band: 4498, r band: 4866, i band: 4584). (1) In the monitored duration, this source is located in a very bright and variable state. The maximum variabilities are Δm_g = 2.013 ± 0.073 mag at g band, Δm_r = 1.900 ± 0.049 mag at r band, and Δm_i = 2.279 ± 0.089 mag at i band. (2) Among the gri intraday lightcurves, there are 104 portions of data sets displaying intraday variabilities (IDVs), with the IDV timescales (ΔT) being in the range of 15.84–375.84 minutes and the biggest variable value Δm = 0.430 ± 0.041 mag. (3) The distributions of ΔT show frequency-dependent behavior, and with the frequency increasing, ΔT tend to be shorter. The variable rates ($V=\tfrac{{\rm{\Delta }}m}{{\rm{\Delta }}T}$) from the g band are more intense than the values (V_r) from the r band, but are more stable than the values (V_i) from the i band. (4) On three days (2020 September 7, 2020 September 19, and 2022 September 7), we find the intraday periodic oscillations, whose periods are around 150 minutes, 232 minutes, and 150 minutes, respectively, and which might come from the source "flickering." (5) Based on the distributions between flux densities (F_gri) and spectral indices (α), they show the bluer-when-brighter behaviors and some uneven locations, which should come from the ministructures of the jet, the shock-induced particle acceleration, or magnetic reconnection in the jet.

The time delay between multiple images of strongly lensed quasars is a powerful tool for measuring the Hubble constant (H₀). To achieve H₀ measurements with higher precision and accuracy using the time delay, it is crucial to expand the sample of lensed quasars. We conduct a search for strongly lensed quasars in the Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging Surveys. The DESI Legacy Surveys comprise 19,000 deg² of the extragalactic sky observed in three optical bands (g, r, and z), making it well suited for the discovery of new strongly lensed quasars. We apply an autocorrelation algorithm to ∼5 million objects classified as quasars in the DESI Quasar Sample. These systems are visually inspected and ranked. Here, we present 436 new multiply lensed and binary quasar candidates, 65 of which have redshifts from Sloan Digital Sky Survey Data Release 16. We provide redshifts for an additional 18 candidates from the SuperNova Integral Field Spectrograph.