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A system of nonlinear Cauchy problem $\partial_t u_i=f_i(t,x, U, \nabla_xU )$ $u_i(0,x)= u_{i,0}(x)$ is studied in function spaces with asymptotic expansion with respect to $t$. To be specific, it is discussed in Borel summable or multisummable function space.It is recognized that these functions are important classes in asymptotic analysis. We study equations under the condition $\{f_i(t,x, U, P)\}_{i=1}^m$ are in these function spaces with respect to $t$ and show $\{u_i(t,x)\}_{i=1}^m$ have also the same summability.

Previous studies on sequence-based extraction of human movement trajectories have an issue of inadequate trajectory representation. Specifically, a pair of locations may not be lined up in a sequence especially when one location includes the other geographically. In this study, we propose a graph representation that retains information on the geographic hierarchy as well as the temporal order of visited locations, and have constructed a benchmark dataset for graph-structured trajectory extraction. The experiments with our baselines have demonstrated that it is possible to accurately predict visited locations and the order among them, but it remains a challenge to predict the hierarchical relations.

We present deep Subaru/FOCAS spectra for two extreme emission line galaxies (EELGs) at $z\sim 1$ with strong {\sc[Oiii]}$\lambda$5007 emission lines, exhibiting equivalent widths (EWs) of $2905^{+946}_{-578}$ \AA\ and $2000^{+188}_{-159}$ \AA, comparable to those of EELGs at high redshifts that are now routinely identified with JWST spectroscopy. Adding a similarly large {\sc [Oiii]} EW ($2508^{+1487}_{-689}$ \AA) EELG found at $z\sim 2$ in the JWST CEERS survey to our sample, we explore for the physical origins of the large {\sc [Oiii]} EWs of these three galaxies with the Subaru spectra and various public data including JWST/NIRSpec, NIRCam, and MIRI data. While there are no clear signatures of AGN identified by the optical line diagnostics, we find that two out of two galaxies covered by the MIRI data show strong near-infrared excess in the spectral energy distributions (SEDs) indicating obscured AGN. Because none of the three galaxies show clear broad H$\beta$ lines, the upper limits on the flux ratios of broad-H$\beta$ to {\sc [Oiii]} lines are small, $\lesssim 0.15$ that are comparable with Seyfert $1.8-2.0$ galaxies. We conduct \texttt{Cloudy} modeling with the stellar and AGN incident spectra, allowing a wide range of parameters including metallicities and ionization parameters. We find that the large {\sc [Oiii]} EWs are not self-consistently reproduced by the spectra of stars or unobscured AGN, but obscured AGN that efficiently produces O$^{++}$ ionizing photons with weak nuclear and stellar continua that are consistent with the SED shapes., Comment: submitted to ApJ

What kinds of and how much data is necessary for language models to induce grammatical knowledge to judge sentence acceptability? Recent language models still have much room for improvement in their data efficiency compared to humans. This paper investigates whether language models efficiently use indirect data (indirect evidence), from which they infer sentence acceptability. In contrast, humans use indirect evidence efficiently, which is considered one of the inductive biases contributing to efficient language acquisition. To explore this question, we introduce the Wug InDirect Evidence Test (WIDET), a dataset consisting of training instances inserted into the pre-training data and evaluation instances. We inject synthetic instances with newly coined wug words into pretraining data and explore the model's behavior on evaluation data that assesses grammatical acceptability regarding those words. We prepare the injected instances by varying their levels of indirectness and quantity. Our experiments surprisingly show that language models do not induce grammatical knowledge even after repeated exposure to instances with the same structure but differing only in lexical items from evaluation instances in certain language phenomena. Our findings suggest a potential direction for future research: developing models that use latent indirect evidence to induce grammatical knowledge., Comment: This paper is accepted at EMNLP 2024 Main

This paper presents Text2Traj2Text, a novel learning-by-synthesis framework for captioning possible contexts behind shopper's trajectory data in retail stores. Our work will impact various retail applications that need better customer understanding, such as targeted advertising and inventory management. The key idea is leveraging large language models to synthesize a diverse and realistic collection of contextual captions as well as the corresponding movement trajectories on a store map. Despite learned from fully synthesized data, the captioning model can generalize well to trajectories/captions created by real human subjects. Our systematic evaluation confirmed the effectiveness of the proposed framework over competitive approaches in terms of ROUGE and BERT Score metrics., Comment: To appear in the International Natural Language Generation Conference (INLG 2024)

With the increase in the more fluent ad texts automatically created by natural language generation technology, it is in the high demand to verify the quality of these creatives in a real-world setting. We propose AdTEC, the first public benchmark to evaluate ad texts in multiple aspects from the perspective of practical advertising operations. Our contributions are: (i) Defining five tasks for evaluating the quality of ad texts and building a dataset based on the actual operational experience of advertising agencies, which is typically kept in-house. (ii) Validating the performance of existing pre-trained language models (PLMs) and human evaluators on the dataset. (iii) Analyzing the characteristics and providing challenges of the benchmark. The results show that while PLMs have already reached the practical usage level in several tasks, human still outperforms in certain domains, implying that there is significant room for improvement in such area.

Euclid will provide deep NIR imaging to $\sim$26.5 AB magnitude over $\sim$59 deg$^2$ in its deep and auxiliary fields. The Cosmic DAWN survey complements the deep Euclid data with matched depth multiwavelength imaging and spectroscopy in the UV--IR to provide consistently processed Euclid selected photometric catalogs, accurate photometric redshifts, and measurements of galaxy properties to a redshift of $z\sim 10$. In this paper, we present an overview of the survey, including the footprints of the survey fields, the existing and planned observations, and the primary science goals for the combined data set., Comment: 16 pages, 10 figures, submitted to A&A; Updated references; Updated author list

We present an [O/Fe] ratio of a luminous galaxy GN-z11 at $z=10.60$ derived with the deep public JWST/NIRSpec data. We fit the medium-resolution grating (G140M, G235M, and G395M) data with the model spectra consisting of BPASS-stellar and CLOUDY-nebular spectra in the rest-frame UV wavelength ranges with Fe absorption lines, carefully masking out the other emission and absorption lines in the same manner as previous studies conducted for lower redshift ($z\sim 2-6$) galaxies with oxygen abundance measurements. We obtain an Fe-rich abundance ratio $\mathrm{[O/Fe]}=-0.37^{+0.43}_{-0.22}$, which is confirmed with the independent deep prism data as well as by the classic 1978 index method. This [O/Fe] measurement is lower than measured for star-forming galaxies at $z\sim 2-3$. Because $z=10.60$ is an early epoch after the Big Bang ($\sim 430$ Myr) and the first star formation (likely $\sim 200$ Myr), it is difficult to produce Fe by Type Ia supernovae (SNeIa) requiring sufficient delay time for white-dwarf formation and gas accretion. The Fe-rich abundance ratio in GN-z11 suggests that the delay time is short, or that the major Fe enrichment is not accomplished by SNeIa but bright hypernovae (BrHNe) and/or pair-instability supernovae (PISNe), where the yield models of BrHNe and PISNe explain Fe, Ne, and O abundance ratios of GN-z11. The [O/Fe] measurement is not too low to rule out the connection between GN-z11 and globular clusters (GCs) previously suggested by the nitrogen abundance, but rather supports the connection with a GC population at high [N/O] if a metal dilution process exists., Comment: 13 pages, 11 figures, accepted for publication in ApJ

Explaining temporal changes between satellite images taken at different times is important for urban planning and environmental monitoring. However, manual dataset construction for the task is costly, so human-AI collaboration is promissing. Toward the direction, in this paper, we investigate the ability of Large-scale Vision-Language Models (LVLMs) to explain temporal changes between satellite images. While LVLMs are known to generate good image captions, they receive only a single image as input. To deal with a par of satellite images as input, we propose three prompting methods. Through human evaluation, we found the effectiveness of our step-by-step reasoning based prompting., Comment: 11 pages, 6 figures

We present the number densities and physical properties of the bright galaxies spectroscopically confirmed at $z\sim7-14$. Our sample is composed of 53 galaxies at $z_\mathrm{spec}\sim7-14$, including recently-confirmed galaxies at $z_\mathrm{spec}=12.34-14.32$ with JWST, as well as new confirmations at $z_\mathrm{spec}=6.583-7.643$ with $-24< M_\mathrm{UV}< -21$ mag using ALMA and Keck. Our JWST/NIRSpec observations have also revealed that very bright galaxy candidates at $z\sim10-13$ identified from ground-based telescope images before JWST are passive galaxies at $z\sim3-4$, emphasizing the necessity of strict screening and spectroscopy in the selection of the brightest galaxies at $z>10$. The UV luminosity functions derived from these spectroscopic results are consistent with a double power-law function, showing tensions with theoretical models at the bright end. To understand the origin of the overabundance of bright galaxies, we investigate their morphologies using JWST/NIRCam high-resolution images obtained in various surveys including PRIMER and COSMOS-Web. We find that $\sim70\%$ of the bright galaxies at $z\sim7$ exhibit clumpy morphologies with multiple sub-components, suggesting merger-induced starburst activity, which is consistent with SED fitting results showing bursty star formation histories. At $z\gtrsim10$, bright galaxies are classified into two types of galaxies; extended ones with weak high-ionization emission lines, and compact ones with strong high-ionization lines including NIV]$\lambda$1486, indicating that at least two different processes (e.g., merger-induced starburst and compact star formation/AGN) are shaping the physical properties of the brightest galaxies at $z\gtrsim10$ and are responsible for their overabundance., Comment: 32 pages, 22 figures, submitted to ApJ

We present results from Atacama Large Millimeter/submillimeter Array (ALMA) spectral line-scan observations at 3-mm and 2-mm bands of three near-infrared-dark (NIR-dark) galaxies behind two massive lensing clusters MACS J0417.5-1154 and RXC J0032.1+1808. Each of these three sources is a faint (de-lensed $S_{\text{1.2 mm}}$ $<$ 1 mJy) triply lensed system originally discovered in the ALMA Lensing Cluster Survey. We have successfully detected CO and [C I] emission lines and confirmed that their spectroscopic redshifts are $z=3.652$, 2.391, and 2.985. By utilizing a rich multi-wavelength data set, we find that the NIR-dark galaxies are located on the star formation main sequence in the intrinsic stellar mass range of log ($M_*$/$M_\odot$) = 9.8 - 10.4, which is about one order of magnitude lower than that of typical submillimeter galaxies (SMGs). These NIR-dark galaxies show a variety in gas depletion times and spatial extent of dust emission. One of the three is a normal star-forming galaxy with gas depletion time consistent with a scaling relation, and its infrared surface brightness is an order of magnitude smaller than that of typical SMGs. Since this galaxy has an elongated axis ratio of $\sim 0.17$, we argue that normal star-forming galaxies in an edge-on configuration can be heavily dust-obscured. This implies that existing deep WFC3/F160W surveys may miss a fraction of typical star-forming main-sequence galaxies due to their edge-on orientation., Comment: 23 pages, 10 figures, Submitted to ApJ

The circumgalactic medium (CGM) serves as a baryon reservoir that connects galaxies to the intergalactic medium and fuels star formation. The spatial distribution of the metal-enriched cool CGM has not yet been directly revealed at cosmic noon (z~2-4), as bright emission lines at these redshifts are not covered by optical integral field units. To remedy this situation, we aim for the first-ever detections and exploration of extended SiII* emission (low-ionization state, LIS), referred to as ``SiII* halos'', at redshifts ranging from z=2 to 4 as a means to trace the metal-enriched cool CGM. We use a sample of 39 galaxies with systemic redshifts of z=2.1-3.9 measured with the [CIII] doublet in the MUSE Hubble Ultra Deep Field catalog, which contains integration times spanning from ~30 to 140 hours. We search for extended SiII*1265, 1309, 1533 emission (fluorescent lines) around individual galaxies. We also stack a subsample of 14 UV-bright galaxies. We report five individual detections of SiII*1533 halos. We also confirm the presence of SiII*1533 halos in stacks for the subsample containing UV-bright sources. The other lines do not show secure detections of extended emission in either individual or stacking analyses. These detections may imply that the presence of metal-enriched CGM is a common characteristic for UV-bright galaxies. To investigate whether the origin of SiII* is continuum pumping as suggested in previous studies, we check the consistency of the equivalent width (EW) of SiII* emission and the EW of SiII absorption for the individual halo object with the most reliable detection. We confirm the equivalence, suggesting that photon conservation works for this object and pointing toward continuum pumping as the source of SiII*. We also investigate SiII* lines in a RAMSES-RT zoom-in simulation including continuum pumping and find ubiquitous presence of extended halos., Comment: 16 pages, 10 figures, 1 table, accepted for publication in A&A

Circumgalactic Lyman-alpha (Ly$\alpha$) nebulae are gaseous halos around galaxies exhibiting luminous extended Ly$\alpha$ emission. This work investigates Ly$\alpha$ nebulae from deep imaging of $\sim12~\mathrm{deg}^2$ sky, targeted by the MAMMOTH-Subaru survey. Utilizing the wide-field capability of Hyper Suprime-Cam (HSC), we present one of the largest blind Ly$\alpha$ nebula selections, including QSO nebulae, Ly$\alpha$ blobs, and radio galaxy nebulae down to typical $2\sigma$ Ly$\alpha$ surface brightness of $(5-10)\times10^{-18}\mathrm{~erg~s^{-1}~cm^{-2}~arcsec^{-2}}$. The sample contains 117 nebulae with Ly$\alpha$ sizes of 40 - 400 kpc, and the most gigantic one spans about 365 kpc, referred to as the Ivory Nebula. Combining multiwavelength data, we investigate diverse nebula populations and associated galaxies. We find a small fraction of Ly$\alpha$ nebulae have QSOs ($\sim7\%$), luminous infrared galaxies ($\sim1\%$), and radio galaxies ($\sim 2\%$). Remarkably, among the 28 enormous Ly$\alpha$ nebulae (ELANe) exceeding 100 kpc, about 80\% are associated with UV-faint galaxies ($M_\mathrm{UV} > -22$), categorized as Type II ELANe. We underscore that Type II ELANe constitute the majority but remain largely hidden in current galaxy and QSO surveys. Dusty starburst and obscured AGN activity are proposed to explain the nature of Type II ELANe. The SED of stacking all Ly$\alpha$ nebulae also reveals signs of massive dusty star-forming galaxies with obscured AGNs. We propose a model to explain the dusty nature where the diverse populations of Ly$\alpha$ nebulae capture massive galaxies at different evolutionary stages undergoing violent assembling. Ly$\alpha$ nebulae provide critical insights into the formation and evolution of today's massive cluster galaxies at cosmic noon., Comment: Accepted by ApJS after minor revision; 26 pages, 10 figures, 3 tables

In this paper, we describe the Fourier-Mukai locus of the derived category of a complex algebraic K3 surface of Picard number one. We also prove that the Fourier-Mukai locus of the derived category of a complex algebraic K3 surface of Picard number one is strictly smaller than it's Matsui spectrum., Comment: 16 pages, comments are welcome!

We present HeI/H$\beta$-flux and He/H-abundance ratios in three JWST galaxies with significant constraints on N/O-abundance ratios, GS-NDG-9422, RXCJ2248-ID, and GLASS150008 at $z\sim 6$ mostly with the spectroscopic coverage from HeI$\lambda$4471 and HeII$\lambda$4686 to HeI$\lambda$7065, comparing with 68 local-dwarf galaxies. We find that these high-$z$ galaxies present strong HeI emission with HeI/H$\beta$ flux ratios generally larger than those of local-dwarf galaxies. We derive He/H with all of the detected HeI, HeII, and $2-3$ hydrogen Balmer lines in the same manner as the local He/H determination conducted for cosmology studies. These high-$z$ galaxies show He overabundance He/H$\gtrsim 0.10$ or high electron density $n_\mathrm{e}\sim 10^{3-4}$ cm$^{-3}$ much larger than local values at low O/H, $12+\log \mathrm{(O/H)}=7-8$. In contrast, we obtain low He/H and $n_\mathrm{e}$ values for our local-dwarf galaxies by the same technique with the same helium and hydrogen lines, and confirm that the difference between the high-$z$ and local-dwarf galaxies are not mimicked by systematics. While two scenarios of 1) He overabundance and 2) high electron density are not clearly concluded, we find that there is a positive correlation on the He/H-N/O or $n_\mathrm{e}$-N/O plane by the comparison of the high-$z$ and local-dwarf galaxies. The scenario 1) suggests that the overabundant helium and nitrogen are not explained by the standard chemical enrichment of core-collapse supernovae, but the CNO-cycle products and equilibrium ratios, respectively. The scenario 2) indicates that the strong helium lines are originated from the central dense clouds of the high-$z$ galaxies by excessive collisional excitation., Comment: 19 pages, 12 figures, accepted for publication in ApJ

We investigate the dynamics of GN-z11, a luminous galaxy at $z=10.60$, carefully analyzing the public deep integral field spectroscopy (IFS) data taken with JWST NIRSpec IFU. While the observations of the IFS data originally targeted a He II clump near GN-z11, we find that CIII]$\lambda\lambda$1907,1909 emission from ionized gas at GN-z11 is bright and spatially extended significantly beyond the point-spread function (PSF). The spatially extended CIII emission of GN-z11 shows a velocity gradient, red- and blue-shifted components in the north and south directions, respectively, which cannot be explained by the variation of [CIII]$\lambda$1907/CIII]$\lambda$1909 line ratios. Assuming the velocity gradient is produced by disk rotation, we perform forward modeling with GalPak$^{3D}$, including the effects of PSF smearing and line blending, and obtain a rotation velocity of $v_{rot}=257^{+138}_{-117}$ km s$^{-1}$, a velocity dispersion of $\sigma_v=91^{+18}_{-32}$ km s$^{-1}$, and a ratio of $v_{rot}/\sigma_v=2.83^{+1.82}_{-1.41}$. The $v_{rot}/\sigma_v$ value would suggest a rotation-dominated disk existing at $z>10$ albeit with the large uncertainties. The rotation velocity agrees with those of numerical simulations predicting a rotating disk formed in the early universe under the condition of mass compaction and weak feedback. While the velocity gradient is consistent with the rotating disk solution, we recognize that galactic outflows can also explain the velocity gradient as well as the extended morphology and the high velocity dispersion found in the outskirt. Higher S/N and resolution data are necessary to conclude the physical origin of the velocity gradient in GN-z11., Comment: Accepted for publication in ApJ

We report the identification of a quasar overdensity in the BOSSJ0210 field, dubbed Cosmic Himalayas, consisting of 11 quasars at $z=2.16-2.20$, the densest overdensity of quasars ($17\sigma$) in the $\sim$10,000 deg$^2$ of the Sloan Digital Sky Survey. We present the spatial distributions of galaxies and quasars and an HI absorption map of the intergalactic medium (IGM). On the map of 465 galaxies selected from the MAMMOTH-Subaru survey, we find two galaxy density peaks that do not fall on the quasar overdensity but instead exist at the northwest and southeast sides, approximately 25 $h^{-1}$ comoving-Mpc apart from the quasar overdensity. With a spatial resolution of 15 $h^{-1}$ comoving Mpc in projection, we produce a three-dimensional HI tomography map by the IGM Ly$\alpha$ forest in the spectra of 23 SDSS/eBOSS quasars behind the quasar overdensity. Surprisingly, the quasar overdensity coincides with neither an absorption peak nor a transmission peak of IGM HI but lies near the border separating opaque and transparent volumes, with the more luminous quasars located in an environment with lesser IGM HI. Hence remarkably, the overdensity region traced by the 11 quasars, albeit all in coherently active states, has no clear coincidence with peaks of galaxies or HI absorption densities. Current physical scenarios with mixtures of HI overdensities and quasar photoionization cannot fully interpret the emergence of Cosmic Himalayas, suggesting this peculiar structure is an excellent laboratory to unveil the interplay between galaxies, quasars, and the IGM., Comment: 19 pages, 11 figures, submitted to ApJ, comments are welcome

We introduce the notion of composition series of triangulated categories. Their lengths yield invariants for these categories. We then focus on composition series of derived categories of certain projective varieties and finite dimensional algebras. We construct composition series of different lengths, for some smooth projective rational surfaces and for certain smooth threefolds. On the other hand, we prove that for derived categories of finite dimensional representations of Dynkin and extended Dynkin quivers, for derived categories of some singular varieties, all composition series have the same length. If this property would also hold for the blow-up of $\mathbb{P}^2$ in $10$ general points, then Krah's phantom subcategory would have infinite length. In particular, it would have infinite chain of thick subcategories., Comment: 35 pages. Results on toric surfaces are generalized. There was a gap in the argument of the length on higher genus curve, and the section on curves is now removed, which will appear in future work

We investigate the physical origins of the Balmer decrement anomalies in GS-NDG-9422 (Cameron et al. 2023) and RXCJ2248-ID (Topping et al. 2024) galaxies at $z\sim 6$ whose $\mathrm{H}\alpha/\mathrm{H}\beta$ values are significantly smaller than $2.7$, the latter of which also shows anomalous $\mathrm{H}\gamma/\mathrm{H}\beta$ and $\mathrm{H}\delta/\mathrm{H}\beta$ values beyond the errors. Because the anomalous Balmer decrements are not reproduced under the Case B recombination, we explore the nebulae with the optical depths smaller and larger than the Case B recombination by physical modeling. We find two cases quantitatively explaining the anomalies; 1) density-bounded nebulae that are opaque only up to around Ly$\gamma$-Ly8 transitions and 2) ionization-bounded nebulae partly/fully surrounded by optically-thick excited H{\sc i} clouds. The case of 1) produces more H$\beta$ photons via Ly$\gamma$ absorption in the nebulae, requiring fine tuning in optical depth values, while this case helps ionizing photon escape for cosmic reionization. The case of 2) needs the optically-thick excited H{\sc i} clouds with $N_2\simeq 10^{12}-10^{13}$ $\mathrm{cm^{-2}}$, where $N_2$ is the column density of the hydrogen atom with the principal quantum number of $n=2$. Interestingly, the high $N_2$ values qualitatively agree with the recent claims for GS-NDG-9422 with the strong nebular continuum requiring a number of $2s$-state electrons and for RXCJ2248-ID with the dense ionized regions likely coexisting with the optically-thick clouds. While the physical origin of the optically-thick excited H{\sc i} clouds is unclear, these results may suggest gas clouds with excessive collisional excitation caused by an amount of accretion and supernovae in the high-$z$ galaxies., Comment: 13 pages, 7 figures, accepted for publication in ApJ

Convergence of the block iterative method in image reconstruction for positron emission tomography (PET) requires careful control of relaxation parameters, which is a challenging task. The automatic determination of relaxation parameters for list-mode reconstructions also remains challenging. Therefore, a different approach would be desirable. In this study, we propose a list-mode maximum likelihood Dykstra-like splitting PET reconstruction (LM-MLDS). LM-MLDS converges the list-mode block iterative method by adding the distance from an initial image as a penalty term into an objective function. LM-MLDS takes a two-step approach because its performance depends on the quality of the initial image. The first step uses a uniform image as the initial image, and then the second step uses a reconstructed image after one main iteration as the initial image. In a simulation study, LM-MLDS provided a better tradeoff curve between noise and contrast than the other methods. In a clinical study, LM-MLDS removed the false hotspots at the edge of the axial field of view and improved the image quality of slices covering the top of the head to the cerebellum. List-mode proximal splitting reconstruction is useful not only for optimizing nondifferential functions but also for converging block iterative methods without controlling relaxation parameters., Comment: 10 pages, 6 figures

Simultaneous multislice (SMS) imaging is a one of the acceleration technique of magnetic resonance imaging. SMS requires accurate sensitivity distributions in the slice plane for each receiving coil. This requirement is difficult to satisfy in practice, limiting the applications of this imaging technique. Here, images are reconstructed by applying deep learning and amplitude modulation to each slice image. Simulation experiments show that image reconstruction can be achieved for both real- and complex-valued images. Image quality tends to decrease with increasing number of simultaneously acquired images. It is also shown that a larger difference in the phase modulation coefficients between slices tends to increase the quality of the reconstructed images. Simulation experiments and initial MR imaging experiments show promising results for this method.

Early galaxy formation, initiated by the dark matter and gas assembly, evolves through frequent mergers and feedback processes into dynamically hot, chaotic structures. In contrast, dynamically cold, smooth rotating disks have been observed in massive evolved galaxies merely 1.4 billion years after the Big Bang, suggesting rapid morphological and dynamical evolution in the early Universe. Probing this evolution mechanism necessitates studies of young galaxies, yet efforts have been hindered by observational limitations in both sensitivity and spatial resolution. Here we report high-resolution observations of a strongly lensed and quintuply imaged, low-luminosity, young galaxy at $z=6.072$ (dubbed the Cosmic Grapes), 930 million years after the Big Bang. Magnified by gravitational lensing, the galaxy is resolved into at least 15 individual star-forming clumps with effective radii of $r_{\rm e}\simeq$ 10--60 parsec (pc), which dominate $\simeq$ 70\% of the galaxy's total flux. The cool gas emission unveils a smooth, underlying rotating disk characterized by a high rotational-to-random motion ratio and a gravitationally unstable state (Toomre $Q \simeq$ 0.2--0.3), with high surface gas densities comparable to local dusty starbursts with $\simeq10^{3-5}$ $M_{\odot}$/pc$^{2}$. These gas properties suggest that the numerous star-forming clumps are formed through disk instabilities with weak feedback effects. The clumpiness of the Cosmic Grapes significantly exceeds that of galaxies at later epochs and the predictions from current simulations for early galaxies. Our findings shed new light on internal galaxy substructures and their relation to the underlying dynamics and feedback mechanisms at play during their early formation phases, potentially explaining the high abundance of bright galaxies observed in the early Universe and the dark matter core-cusp problem., Comment: Submitted. 44 pages, 14 figures, 5 tables. Comments are welcome! See also the companion papers on arXiv. Valentino+2024: arXiv:2402.17845 Gim\'enez-Arteaga+2024: arXiv:2402.17875

We present JWST/NIRCam observations of a strongly-lensed, multiply-imaged galaxy at $z=6.072$, with magnification factors >~20 across the galaxy. We perform a spatially-resolved analysis of the physical properties at scales of ~200 pc, inferred from SED modelling of 5 NIRCam imaging bands on a pixel-by-pixel basis. We find young stars surrounded by extended older stellar populations. By comparing H$\alpha$+[NII] and [OIII]+H$\beta$ maps inferred from the image analysis with our additional NIRSpec IFU data, we find that the spatial distribution and strength of the line maps are in agreement with the IFU measurements. We explore different parametric SFH forms with Bagpipes on the spatially-integrated photometry, finding that a double power-law star formation history retrieves the closest value to the spatially-resolved stellar mass estimate, and other SFH forms suffer from the dominant outshining emission from the youngest stars, thus underestimating the stellar mass - up to ~0.5 dex-. On the other hand, the DPL cannot match the IFU measured emission lines. Additionally, the ionizing photon production efficiency may be overestimated in a spatially-integrated approach by ~0.15 dex, when compared to a spatially-resolved analysis. The agreement with the IFU measurements points towards the pixel-by-pixel approach as a way to mitigate the general degeneracy between the flux excess from emission lines and underlying continuum, especially when lacking photometric medium-band coverage and/or IFU observations. This study stresses the importance of studying galaxies as the complex systems that they are, resolving their stellar populations when possible, or using more flexible SFH parameterisations. This can aid our understanding of the early stages of galaxy evolution by addressing the challenge of inferring robust stellar masses and ionizing photon production efficiencies of high redshift galaxies., Comment: Submitted to A&A; 13 pages. See also the companion papers on arXiv today: Fujimoto+2024 and Valentino+2024

We present the results of a ~60-hr observational campaign with ALMA targeting a spectroscopically confirmed and lensed sub-$L^\star$ galaxy at z=6.07, identified during the ALMA Lensing Cluster Survey (ALCS). We sample the dust continuum emission from rest frame 90 to 370 $\mu$m at six different frequencies and set constraining upper limits on the molecular gas line emission and content via CO(7-6) and [CI](2-1) for two lensed images with $\mu\gtrsim20$. Complementing these sub-mm observations with deep optical and near-IR photometry and spectroscopy with JWST, we find this galaxy to form stars at a rate of SFR~7 Msun/yr, ~50-70% of which is obscured by dust. This is consistent with what is expected for a $M_\star$~7.5$\times10^{8}$ Msun object by extrapolating the $M_\star$-obscured SFR fraction relation at z<2.5 and with observations at 5

The chemical composition of galaxies offers vital insights into their formation and evolution. A key aspect of this study is the correlation between helium abundance (He/H) and metallicity, which is instrumental in estimating the primordial helium produced during Big Bang nucleosynthesis. We investigate the chemical enrichment history of low-metallicity galaxies, with a particular focus on extremely metal-poor galaxies (EMPGs), using one-zone models. Our one-zone model, employing the Limongi & Chieffi (2018) yield, aligns well with observed high He/H ratios at low metallicities and successfully reproduces Fe/O ratios similar to those found in EMPGs. In contrast, the Nomoto et al. (2013) yield does not fully match the high Fe/O ratios observed in EMPGs. Furthermore, we explored models incorporating supermassive stars (SMS) as Pop III stars and intermittent star formation, both of which produced higher He/H ratios than the standard one-zone model. A model calculation that incorporates SMS yields effectively explain young galaxies (< $10^8$ years) with metallicities $(\mathrm{O/H}) \times 10^5 < 20$ and $\mathrm{He/H} > 0.085$. Notably, the model, where the outer envelope of the SMS's CO core is completely ejected, achieves $\mathrm{He/H} > 0.12$, aligning with the properties of high-$z$ galaxies recently discovered by JWST. Additionally, these models predict high N/O, consistent with JWST observations in the early universe., Comment: 15 pages, 7 figures, 2 table, submitted to ApJ

We present the evolution of Ly$\alpha$ emission derived from 53 galaxies at $z=6.6-13.2$ that are identified by multiple JWST/NIRSpec spectroscopy programs of ERS, GO, DDT, and GTO. These galaxies fall on the star-formation main sequence and are the typical star-forming galaxies with UV magnitudes of $-22.5\leq M_\mathrm{UV}\leq-17.0$. We find that 15 out of 53 galaxies show Ly$\alpha$ emission at the $>3\sigma$ levels, and obtain Ly$\alpha$ equivalent width (EW) measurements and stringent $3\sigma$ upper limits for the 15 and 38 galaxies, respectively. Confirming that Ly$\alpha$ velocity offsets and line widths of our galaxies are comparable with those of low-redshift Ly$\alpha$ emitters, we investigate the redshift evolution of the Ly$\alpha$ EW. We find that Ly$\alpha$ EWs statistically decrease towards high redshifts on the Ly$\alpha$ EW vs. $M_{\rm UV}$ plane for various probability distributions of the uncertainties. We then evaluate neutral hydrogen fractions $x_{\rm HI}$ with the Ly$\alpha$ EW redshift evolution and the cosmic reionization simulation results on the basis of a Bayesian inference framework, and obtain $x_{\rm HI}<0.79$, $=0.62^{+0.15}_{-0.36}$, and $0.93^{+0.04}_{-0.07}$ at $z\sim7$, $8$, and $9-13$, respectively. These moderately large $x_{\rm HI}$ values are consistent with the Planck CMB optical depth measurement and previous $x_{\rm HI}$ constraints from galaxy and QSO Ly$\alpha$ damping wing absorptions, and strongly indicate a late reionization history. Such a late reionization history suggests that major sources of reionization would emerge late and be hosted by moderately massive halos in contrast with the widely-accepted picture of abundant low-mass objects for the sources of reionization., Comment: Accepted for publication in ApJ

We study outflows in 130 galaxies with -221000 km/s. With the velocity shift and line widths of the outflow broad lines, we obtain ~80-500 km/s for the outflow velocities. We find that the outflow velocities as a function of star-formation rate are comparable to or higher than those of galaxies at z~1, accounting for the selection bias, while the outflow velocities of AGN are large but not significantly different from the others. Interestingly, these outflow velocities are typically not high enough to escape from the galactic potentials, suggestive of fountain-type outflows, which are concluded on the basis of thorough comparisons with recent JWST results. We estimate mass loading factors ${\eta}$ to be 0.1-1 that are not particularly large, but comparable with those of z~1 outflows. The large fraction of galaxies with outflows (30% with high resolution data) provides constraints on outflow parameters, suggesting a wide opening angle of >45 deg and a large duty-cycle of >30%, which gives a picture of more frequent and spherical outflows in high-z galaxies., Comment: 16 pages, 11 figures, submitted to the Astrophysical Journal

Weakly-supervised learning has emerged as a promising approach to leverage limited labeled data in various domains by bridging the gap between fully supervised methods and unsupervised techniques. Acquisition of strong annotations for detecting sound events is prohibitively expensive, making weakly supervised learning a more cost-effective and broadly applicable alternative. In order to enhance the recognition rate of the learning of detection of weakly-supervised sound events, we introduce a Frame Pairwise Distance (FPD) loss branch, complemented with a minimal amount of synthesized data. The corresponding sampling and label processing strategies are also proposed. Two distinct distance metrics are employed to evaluate the proposed approach. Finally, the method is validated on the DCASE 2023 task4 dataset. The obtained experimental results corroborated the efficacy of this approach., Comment: Submitted to ICASSP 2024

Learning meaningful frame-wise features on a partially labeled dataset is crucial to semi-supervised sound event detection. Prior works either maintain consistency on frame-level predictions or seek feature-level similarity among neighboring frames, which cannot exploit the potential of unlabeled data. In this work, we design a Local and Global Consistency (LGC) regularization scheme to enhance the model on both label- and feature-level. The audio CutMix is introduced to change the contextual information of clips. Then, the local consistency is adopted to encourage the model to leverage local features for frame-level predictions, and the global consistency is applied to force features to align with global prototypes through a specially designed contrastive loss. Experiments on the DESED dataset indicate the superiority of LGC, surpassing its respective competitors largely with the same settings as the baseline system. Besides, combining LGC with existing methods can obtain further improvements. The code will be released soon., Comment: submitted to ICASSP 2024

We present the rest-frame optical and UV surface brightness (SB) profiles for $149$ galaxies with $M_{\rm opt}< -19.4$ mag at $z=4$-$10$ ($29$ of which are spectroscopically confirmed with JWST NIRSpec), securing high signal-to-noise ratios of $10$-$135$ with deep JWST NIRCam $1$-$5\mu$m images obtained by the CEERS survey. We derive morphologies of our high-$z$ galaxies, carefully evaluating the systematics of SB profile measurements with Monte Carlo simulations as well as the impacts of a) AGNs, b) multiple clumps including galaxy mergers, c) spatial resolution differences with previous HST studies, and d) strong emission lines, e.g., H$\alpha$ and [OIII], on optical morphologies with medium-band F410M images. Conducting S\'ersic profile fitting to our high-$z$ galaxy SBs with GALFIT, we obtain the effective radii of optical $r_{\rm e, opt}$ and UV $r_{\rm e, UV}$ wavelengths ranging $r_{\rm e, opt}=0.05$-$1.6$ kpc and $r_{\rm e, UV}=0.03$-$1.7$ kpc that are consistent with previous results within large scatters in the size luminosity relations. However, we find the effective radius ratio, $r_{\rm e, opt}/r_{\rm e, UV}$, is almost unity, $1.01^{+0.35}_{-0.22}$, over $z=4$-$10$ with no signatures of past inside-out star formation such found at $z\sim 0$-$2$. There are no spatial offsets exceeding $3\sigma$ between the optical and UV morphology centers in case of no mergers, indicative of major star-forming activity only found near a mass center of galaxies at $z\gtrsim 4$ probably experiencing the first phase of inside-out galaxy formation., Comment: 33 pages, 18 figures, 6 tables, accepted