We present maps of the “Survey of Water and Ammonia toward the Galactic center” (SWAG). SWAG was observed over three years (∼550 h) with the Australia Telescope Compact Array (ATCA) and covers the entire Central Molecular Zone (CMZ) at about 26” or ∼1 pc resolution. The observed 21.2–25.6 GHz range contains tens of spectral lines and 4 GHz of continuum. Here, we present some final maps. These include multiple NH3 lines, radio recombination lines, shock tracers like HNCO and methanol (CH3OH), high resolution 22 GHz water masers, and a continuum map. The maps are the foundation for ongoing comprehensive temperature mapping of the CMZ, including the identification of heating mechanisms, the characterization of water maser sources as young stellar objects or AGB stars, as well as chemistry, dynamics, and star formation studies of the ISM in this unique environment.

We have recently hit the milestone of 5,000 exoplanets discovered. In stark contrast with the Solar System, most of the exoplanets we know to date orbit extremely close to their host stars, causing them to lose copious amounts of gas through atmospheric escape at some stage in their lives. In some planets, this process can be so dramatic that they shrink in timescales of a few million to billions of years, imprinting features in the demographics of transiting exoplanets. Depending on the transit geometry, ionizing conditions, and atmospheric properties, a planetary outflow can be observed using transmission spectroscopy in the ultraviolet, optical or near-infrared. In this review, we will discuss the main techniques to observe evaporating exoplanets and their results. To date, we have evidence that at least 28 exoplanets are currently losing their atmospheres, and the literature has reported at least 42 non-detections.

Pristine gas accretion is expected to be the main driver of sustained star formation in galaxies. We measure the required amount of accreted gas at each moment over a galaxy’s history to produce the observed metallicity at that time given its star-forming history. More massive galaxies tend to have higher accretion rates and a larger drop of the accretion rate towards the present time. Within the same mass bin galaxies that are currently star-forming or in the Green Valley have similar, sustained, accretion histories while retired galaxies had a steep decline in the past. Plotting the T80 of the individual accretion histories, a measure of how sustained they are, versus the stellar mass and current sSFR we see a distribution such that currently star-forming galaxies have sustained or recent accretion and retired galaxies have declined accretion histories.

Existence of the cold-mode gas accretion along with the hot-mode accretion can explain the diversity in the galactic star formation history across galaxy mass. We examine the role of various physical processes in producing the observed diversity.

The evolution of giant molecular clouds (GMCs), which are the main sites of star formation, is essential for unraveling how stars form and how galaxies evolve. We analyzed the M33 CO(J = 2–1) data with spatial resolution of 39 pc obtained by ALMA-ACA 7 m array combined with IRAM 30 m. We identified 736 GMCs and classified them into three types; Type I: associated with no Hii regions, Type II: associated with Hii regions with the Hα luminosity L(Hα) < 1037.5 erg s-1, Type III: associated with Hii regions with L(Hα) > 1037.5erg s-1. We found that mass, size, and velocity dispersion of GMCs slightly increase in the order of Type I, II, and III GMCs. Type III GMCs mainly exist in the spiral arm, while many of Type I and Type II GMCs are distributed in the inter-arm. Assuming that the star formation proceeds steadily, we roughly estimated the total GMC lifetime of 30 Myr.

Local Group (LG), the nearest and most complete galactic environment, provides valuable information on the formation and evolution of the Universe. Studying galaxies of different sizes, morphologies, and ages can provide this information. For this purpose, we chose the And IX dSph galaxy, which is one of the observational targets of the Isaac Newton Telescope (INT) survey. A total of 50 long-period variables (LPVs) were found in And IX in two filters, Sloan i' and Harris V at a half-light radius of 2.5 arcmin. The And IX’s star formation history (SFH) was constructed with a maximum star formation rate (SFR) of about 0.00082 ± 0.00031 M⊙ yr−1, using LPVs as a tracer. The total mass return rate of LPVs was calculated based on the spectral energy distribution (SED) of about 2.4 × 10−4 M⊙ yr−1. The distance modulus of 24.56−0.15+0.05 mag was estimated based on the tip of the red giant branch (TRGB).

To understand the physical properties of the interstellar medium (ISM) in various scales, we should investigate it with pc-scale resolution over kpc scale coverage. Here, we report the sub-kpc scale Gas Density Histogram (GDH) of the Milky Way. GDH is a histogram of averaged density and corresponds to the probability density distribution (PDF) of gas volume density. We use galactic plain survey data (l =10∘− 50∘) at 12CO and 13CO (J = 1 − 0) obtained as a part of the FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45m telescope (FUGIN). With this method and data, we are free from spatial structure and molecular cloud identification. GDH can be well fitted with single or double log-normal distribution; which we call as the low-density log-normal (L-LN) and high-density log-normal (H-LN) components. We found both the H-LN fraction (fH) and L-LN width (σL) along the gas density axis show a coherent structure on the longitude-velocity diagram. It suggests that there is a relationship between the ISM property and kpc scale structure in the Milky Way.

The KEPLER transit survey with follow-up spectroscopic observations has discovered numerous small planets (super-Earths/sub-Neptunes) and revealed intriguing features of their sizes, orbital periods, and their relations between adjacent planets. The planet size distribution exhibits a bimodal distribution separated by a radius gap at around 1.8 Earth radii. Besides, these small planets within multiple planetary systems show that adjacent planets are similar in size and their period ratios of adjacent planet pairs are similar as well, a phenomenon often dubbed as peas-in-a-pod in the exoplanet community. While the radius gap has been predicted and theorized for years, whether it can be relevant to the orbital architecture peas-in-a-pod is physically unknown. For the first time, we attempted to model both features together through planet formation and evolution processes involving giant impacts and photoevaporation. We showed that our model is generally consistent with the KEPLER results but with a smaller radius gap. The impact of Kubyshikina’s model for photoevaporation on our model is discussed.

Existence of cold-mode gas accretion along with the hot-mode accretion of the shock-heated gas can explain the bimodality in the elemental abundance of the Milky Way disk stars as well as the mass-dependence of galaxy morphology represented by mass ratios of thin disks, thick disks, and bulges.

High-energy stellar irradiation can photoevaporate planetary atmospheres, which can be observed in spectroscopic transits of hydrogen lines. Here, we investigate the effect of planetary magnetic fields on the observational signatures of atmospheric escape in hot Jupiters.

The interplay between star formation (SF) activity and active galactic nuclei (AGN) governs the co-evolution of supermassive black holes (SMBHs) and their host galaxies. AGN feedback has been hailed as the de facto process to suppress, or even shut down SF within the framework of hierarchical galaxy merger based on the current ΛCDM paradigm. However, it is unclear what physical processes regulate the growth of SMBHs and how SMBHs and their evolution are interconnected with their host galaxies when SMBHs and host galaxies are of hugely different physical scales. In fact, there has been no observational evidence to show that AGN feedback works, but rather some evidence to speculate that the more powerful AGNs reside in the more actively star-forming host galaxies. While it is difficult to measure the amount of SF from AGN host galaxies, polycyclic aromatic hydrocarbon (PAH) emission features emerged as good proxies for this purpose. Although having several caveats as SFR indicators, such as metallicity dependency, and non-SF contribution from evolved stellar populations, or AGNs, PAH emissions have been utilized to investigate SF activity of AGN host galaxies with varying results. Utilizing the slitless spectroscopic apability of the AKARI Infrared Camera, we obtained the spectra in the wavelength range of 2∼5 μm from extended regions of 79 type 1 AGN host galaxies to detect and measure the 3.3 μm (PAH) emission feature as star formation rate proxy. Based on 18 sample galaxies, we found that the luminosity of the 3.3 μm PAH emission feature is strongly correlated with AGN luminosity, except for ultra-luminous infrared galaxies (ULIRGs). Therefore, we suggest that host galaxies with stronger AGN activities have stronger star formation activities. However, it is still unclear why ULIRGs deviate from the correlation, not to mention why the detection rate of the 3.3 μm emission feature is so low. High spatial resolution imaging not only for the circumnuclear region of AGN host galaxies, but also for entire galaxies should help the cause. We present the prospective studies to diagnose SF regulation for AGN host galaxies with various space telescope facilities, such as JWST, and SPHEREx.

The main goal of the Vera C. Rubin observatory is to perform the 10 year Legacy Survey of Space and Time (LSST). This future state-of-art observatory will open the new window to study billions of galaxies from Local Universe as well as the high redshift objects. In this work we employ simulated LSST observations and uncertainties, based on the 50 385 real galaxies within the redshift range 0 < z < 2.5 from the ELAIS-N1 and COSMOS fields of the Herschel Extragalactic Legacy Project (HELP) survey, to constrain the physical properties of normal star-forming galaxies, such as their star formation rate (SFR), stellar mass (Mstar), and dust luminosity (Ldust). We fit their spectral energy distributions (SEDs) using the Code Investigating GALaxy Emission (CIGALE). The stellar masses estimated based on the LSST measurements agree with the full UV to far-IR SED, while we obtain a clear overestimate of the dust-related properties (SFR, Ldust) estimated with LSST. We investigate the cause of this result and find that it is necessary to employ auxiliary rest-frame mid-IR observations, simulated UV observations, or the far-UV attenuation (AFUV)-Mstar relation to correct for the overestimate.

We model evolution of exoplanets of S-type in close binary systems at the stage when the companion starts to lose mass via a slow stellar wind. At this stage an accretion disc is formed around the planets’ host. Detailed structure of such discs is calculated in quasi-stationary and non-stationary approaches. We model migration of planets embedded in these discs.

We examine the physical conditions required for the formation of H2 in the solar neighborhood by comparing H i emission and absorption spectra toward 58 lines of sight at b < −5∘ to CO(1–0) and dust data. Our analysis of CO-associated cold and warm neutral medium (CNM and WNM) shows that the formation of CO-traced molecular gas is favored in regions with high column densities where the CNM becomes colder and more abundant. In addition, our comparison to the one-dimensional steady-state H i-to-H2 transition model of Bialy et al. (2016) suggests that only a small fraction of the clumpy CNM participates in the formation of CO-traced molecular gas. Another possible interpretation would be that missing physical and chemical processes in the model could play an important role in H2 formation.

The TYPHOON program is producing an atlas of spectroscopic data cubes of 44 large-angular-sized galaxies with complete spatial coverage from 3650–9000 Å. This survey provides an unparalleled opportunity to study variations in the interstellar medium (ISM) properties within individual H ii regions across the entire star-forming disks of nearby galaxies. This can provide key insights into the spatial distribution and resolved properties of the ISM to understand how efficiently metals are mixed and redistributed across spirals and dwarf galaxies. In this Proceeding, we present early science results from six nearby spiral galaxies as part of the TYPHOON program from Grasha et al. (2022). We use HIIPhot to identify the H ii regions within the galaxy based on the surface brightness of the Hα emisison line and measure variations of the H ii region oxygen abundance. In this initial work, we find that while the spiral pattern plays a role in organizing the ISM, it alone does not establish the relatively uniform azimuthal variations we observe across all the galaxies. Differences in the metal abundances are more likely driven by the strong correlations with the local physical conditions. We find a strong and positive correlation between the ionization parameter and the local abundances as measured by the relative metallicity offset Δ(O/H), indicating a tight relationship between local physical conditions and their localized enrichment of the ISM. These variations can be explained by a combination of localized, star formation-driven self-enrichment and large-scale mixing-driven dilution due to the passing of spiral density waves.

The role of atmospheric evaporation in shaping exoplanet populations remains a major unsolved problem in the literature. Observational evidence, like the bimodal distribution of exoplanet radii, suggests a catastrophic past in which exoplanets with masses of approximately 1–10M⊕ often lose their primordial envelopes and experience a drastic reduction in their radii. Our knowledge of the mechanisms behind atmospheric evaporation remains nebulous, with new models regularly introduced in the literature. Understanding the principles behind these models and knowing when to apply them is essential for constraining how planets evolve. This communication reviews the mechanisms behind atmospheric evaporation by exploring observations and theory, as well as introducing some of the principles in the forthcoming paper Modirrousta-Galian & Korenaga (in press).

Magnetism can greatly impact the evolution of stars. In some stars with OBA spectral types there is direct evidence via the Zeeman effect for stable, large-scale magnetospheres, which lead to the spin-down of the stellar surface and reduced mass loss. So far, a comprehensive grid of stellar structure and evolution models accounting for these effects was lacking. For this reason, we computed and studied models with two magnetic braking and two chemical mixing schemes in three metallicity environments with the mesa software instrument. We find notable differences between the subgrids, which affects the model predictions and thus the detailed characterisation of stars. We are able to quantify the impact of magnetic fields in terms of preventing quasi-chemically homogeneous evolution and producing slowly-rotating, nitrogen-enriched (“Group 2”) stars. Our model grid is fully open access and open source.

This work aims to represent the physical properties of a sample of infrared-bright dust-obscured galaxies (DOGs) studied by Suleiman et al. (2022) by fitting the spectral energy distributions (SEDs). Twenty-eight DOGs were examined at redshifts 0.47 ≤ z ≤ 1.63 discovered by combining images of the Subaru Hyper Suprime-Cam (HSC) survey, VISTA Kilo-degree Infrared Galaxy (VIKING) survey, and the Wide-field Infrared Survey Explorer (WISE) all-sky survey, and detected at Herschel Spectral and Photometric Imaging Receiver (SPIRE) bands. The results show a correlation between the star formation rate (SFR) and the dust luminosity of Suleiman et al. (2022) DOG sample, the SFR ranges of the sample according to different redshifts, and a comparison between Suleiman et al. (2022) sample and other samples of DOGs.

Massive stars drive strong winds that impact the surrounding interstellar medium, producing parsec-scale bubbles for isolated stars and superbubbles around young clusters. These bubbles can be observed across the electromagnetic spectrum, both the wind itself and the swept up interstellar gas. Runaway massive stars produce bow shocks that strongly compresses interstellar gas, producing bright infrared, optical and radio nebulae. With the detection of non-thermal radio emission from bow shocks, particle acceleration can now also be investigated. I review research on wind bubbles and bow shocks around massive stars, highlighting recent advances in infrared, radio and X-ray observations, and progress in multidimensional simulations of these nebulae. These advances enable quantitative comparisons between theory and observations and allow to test the importance of some physical processes such as thermal conduction and Kelvin-Helmholtz instability in shaping nebulae and in constraining the energetics of stellar-wind feedback to the interstellar medium.

Azimuthal variations in HI velocity dispersion do not correlate with variations in the star formation rate per unit area, SFR/A, suggesting that local star formation does not increase HI turbulence significantly. These variations are determined for each pixel in HI and FUV maps of THINGS and LITTLE THINGS galaxies by subtracting the average radial profiles from the measured quantities. The kinetic energy density and HI surface density increase slightly with SFR/A, suggesting that feedback goes into pushing the local dense gas around without increasing the velocity dispersion. We suggest that star formation feedback does not promote large-scale stability against gravitational forces through turbulence regulation, and that gravitational energy from recurrent instabilities drives turbulence on galactic scales.