Astrophysics of Galaxies
A triple-induced merger in T Ori C, solves the proplyd lifetime problem and the curiously young shell of M42
Maite Wilhelm, Alessandro Alberto Trani and Simon Portegies Zwart
There has long been a tension between the stellar ages in the Orion Nebula Cluster and the rapid external photoevaporation of its protoplanetary discs. Recently, the shell of the Orion Nebula has similarly been found to be dynamically younger than the
stars. We propose a new scenario to resolve both age problems. In our scenario the ONC's most massive
star, $\theta^1$~Ori~C1, formed from the merger between two binary
stars induced by vZLK oscillations due to the present-day binary companion $\theta^1$~Ori~C2. This merger, happening between the last episode of
star formation and today, resulted in an increased luminosity, leading to stronger external photoevaporation and accelerated expansion of the shell. {We use Monte Carlo simulations to explore both whether a sudden brightening of $\theta^1$~Ori~C1 could reconcile the stellar ages and shell expansion, and whether triple progenitors to $\theta^1$~Ori~C\, could result in stellar mergers on the relevant timescale. A sudden brightening of $\theta^1$~Ori~C1 a few hundred thousand years ago can reproduce today's shell while maintaining a system age close to the stellar age. However, the required increase in stellar wind luminosity is greater than a simple merger can explain. At lower luminosity, the mixing of a relatively greater amount of cool photoevaporative wind material into the hot bubble could result in the required increase, and we identify a lower limit on the required strength of this effect. Additionally, we find that progenitor triples merge readily, on timescales even shorter than the scenario would require. These mergers could be deferred by increased pre-main sequence tidal effects, rotation, and perturbing encounters with other cluster members. Our proposed scenario with a merger driven by von Zeipel-Lidov-Kozai
evolution solves two problems; the Orion Nebula's proplyd problem and the shell lifetime problems.
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Astrophysics of Galaxies
Cosmic Collisions I: Optical Morphologies for MIRI-selected galaxies from the PRIMER survey
Gregory Troiani, Allison Kirkpatrick, Leyna Bajaj et al. (+7 more)
We present the first results of visual morphology classifications from the
Cosmic Collisions project, comprising 14,657
galaxies from the JWST Public Release IMaging for Extragalactic Research (PRIMER) survey. The sample consists of
galaxies detected with MIRI F770W and spans the epoch of peak
cosmic star formation (1<z<3). We produce rest-frame optical and observed-frame mid-IR images and enlisted citizen science volunteers through the Zooniverse platform to classify
galaxy morphology, surface features, and interactions. The project accumulated 304,524 classifications from more than 4,700 volunteers. We find that mid-IR selected
galaxies have significantly different morphologies relative to optical and near-IR selected
galaxies, favoring dust-rich disk
galaxies at z<2 and compact systems at z>2. This inverts findings from optical selection, which shows
galaxies becoming more bulge-dominated and elliptical over
cosmic time. In addition, we identify a population of
galaxies with disk-like optical morphologies and luminous mid-IR point-source cores that may represent obscured AGN candidates, offering a promising path to identify AGNs based on imaging alone. Comparison with visual classifications from HST imaging demonstrates the impact of JWST's improved sensitivity and resolution on the identification of
galaxy structure and interactions, with systems previously identified by HST as compact, smooth, or featureless showing significant extended and internal structure in JWST. These results provide a foundation for future investigations into the connection between morphology, dust structure,
star formation, and AGN activity.
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All authors Gregory Troiani, Allison Kirkpatrick, Leyna Bajaj, Joseph Havens, Jackson Stephens, Anton M. Koekemoer, James S. Dunlop, Adriano Fontana, Norman Grogin, Pablo G. Pérez-González
Astrophysics of Galaxies · Cross-listed from astro-ph.HE
NEXUS: Discovery of a Luminous Young Transient at $z=5$
Ming-Yang Zhuang, Yue Shen, Lei Hu et al. (+8 more)
We report the discovery of AT 2026abck, a young transient in a
star-forming
galaxy at $z=5.017\pm0.001$, identified from Year-2 observations of the NEXUS JWST treasury program. AT 2026abck was detected on 2026 Aug 7 in NIRCam F200W imaging, with contemporaneous detection from parallel NIRCam F150W+F277W imaging. It brightened by $>1.4$ mag in F200W over $\lesssim 12$ rest-frame days, as inferred from the last non-detection. AT 2026abck has nearly identical magnitudes of $\sim27.4$ mag in F150W, F200W, and F277W, and is undetected in F444W ($>27.9$ mag, 3$\sigma$). It is the first robustly detected $z\gtrsim 5$ transient in a non-
lensing field. A blackbody fit yields a hot photosphere ($\sim1.7\times10^4\, \mathrm{K}$) with a radius of $\sim7\times10^{14}$ cm ($\sim46$ au) and a bolometric luminosity of $\sim3\times10^{43}\, {\rm erg\, s^{-1}}$. Its off-
nucleus location and hot, UV-bright SED favor a core-collapse
supernova origin, while its temperature and luminosity exceed those of normal SNe II at comparable early phases. We estimate that AT 2026abck was detected $\sim4$-10 rest-frame days after explosion. The host is an intermediate-mass ($M_*\approx10^{9.8}\,M_\odot$),
star-forming (${\rm SFR}\approx20\,M_\odot\,{\rm yr^{-1}}$)
galaxy on the $z\approx5$ main sequence, $\sim3.3$ dex more massive than the ultra-faint host of the lensed SN Eos at $z=5.13$. Together, the two events show that CCSNe at $z>5$ occur across a wide range of host environments, and AT 2026abck demonstrates that high-cadence blank-field JWST surveys can capture high-
redshift SNe during their early, UV-bright phase.
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All authors Ming-Yang Zhuang, Yue Shen, Lei Hu, Justin D. R. Pierel, Zhiwei Pan, Zachary Stone, Adam J. Burgasser, Xiaohui Fan, Jenny E. Greene, Junyao Li, Feige Wang
Astrophysics of Galaxies
A New Hope for AGN SED Fitting: X-Ray Spectral Analysis of 12MGS AGN with the C2PO-Torus Model
Carys J. E. Gilbert, Lucia Marchetti, Luigi Barchiesi et al. (+8 more)
In this paper, we present the results of comprehensive, broadband X-ray spectral analysis of a subsample of 43 mid-Infrared (IR) selected
star-forming active galactic
nuclei (AGN). We analysed archival NuSTAR, Chandra, and XMM-Newton data, and present the first pointed X-ray observation of IRASF03450+0055. We introduce a new physically-based X-ray spectral model, C2PO-
Torus, based on a two-phase clumpy
torus geometry. It is designed to provide constraints on physical parameters of the
torus that can be directly linked to the parameters of the AGN model SKIRTOR. This model will allow us to exploit the synergies between the X-ray and IR regimes, place stronger constraints on the
torus properties, and improve spectral energy distribution (SED) fitting by providing priors for the SKIRTOR parameters. We compare the results from the C2PO-
Torus fitting to those obtained from traditional models, finding that it is an extremely effective tool for fitting a wide variety of X-ray spectra. We observe that our sample closely follows the established L_[OIII] - L_X AGN relation, while presenting an IR and
Radio excess with respect to the L_X - L_12micron and L_X - L_1.4GHz AGN relations at low luminosities. We believe that this excess is due to contamination from
star formation related emission. We anticipate that the C2PO-
Torus model will aid substantially in completing full-spectrum SED fitting of this sample, allowing us to properly disentangle the different emission components of these objects, which are local analogues of AGN at
Cosmic Noon.
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All authors Carys J. E. Gilbert, Lucia Marchetti, Luigi Barchiesi, Mattia Vaccari, Cristian Vignali, Stefano Marchesi, Francesca Pozzi, Francesco Salvestrini, Anna Feltre, Malebo Moloko, Carlotta Gruppioni
Astrophysics of Galaxies · Cross-listed from astro-ph.HE
Cosmic-neighbor-associated distances to VHE and candidate VHE BL Lacs via SDSS photometric redshifts
Karri I. I. Koljonen and Elina Lindfors
BL Lac objects have distances that are difficult to estimate because their optical spectra rarely show identifiable emission or absorption lines. We present a method to constrain BL Lac distances by associating them with their
cosmic neighborhoods (local overdensities in the
cosmic web) identified in optical fields. Distances to
galaxies in these neighborhoods are estimated using the Sloan Digital Sky Survey (SDSS) photometric
redshifts. Using
cosmic-neighborhood associations previously established from multi-object spectroscopy and BL Lacs with spectroscopically measured
redshifts as control samples, we find that the
redshifts of the associated neighborhoods can be recovered with an accuracy of $\Delta z \sim 0.02-0.04$. When multiple candidate neighborhoods are present in the field, we rank the candidate associations using a central-location criterion. In 50% of cases, the BL Lac is associated with the correct neighborhood. We provide distance estimates for BL Lac objects without secure
redshift measurements, focusing on sources detected at very high energies (VHE; $E>100$,GeV) and on candidate VHE emitters. Combining intervening absorption systems, host-
galaxy imaging, $\gamma$-ray constraints, and our SDSS group-association method, we propose likely
redshifts for TXS 0141$+$268 ($z\sim0.93-0.95$), PKS 0735$+$178 ($z=0.64$), 3FHL J0905.5$+$1357 ($z=0.644$), B2 0912$+$29 ($z = 0.53$), 3FHL J1120.8$+$4212 ($z=0.363$), BZB J1243$+$3627 ($z=0.485$), 3FHL J1253.1$+$5300 ($z=0.664$), and RX J2156.0$+$1818 ($z=0.635$). Finally, we discuss how forthcoming narrow-band photometric-
redshift surveys can improve blazar distance estimates via group-association techniques.
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Astrophysics of Galaxies
Learning Gaia: A Generative Model Trained on the Gaia Data Release 3 Source Catalog
John Soltis
I train a conditional flow matching model on the positions, photometry, and astrometry of $\sim$ 579 million sources from the Gaia Data Release 3 Source Catalog. Using a probabilistic masking scheme during training, I develop a model capable of generating mock Gaia catalog sources with and without partial measurements of real Gaia sources. The model can produce coarse-grained mock Gaia Source Catalogs that reproduce the Milky Way disk and Magellanic Clouds, and can impute photometric and kinematic information. The model fails to reproduce small, distinct subpopulations like $\omega$ Centauri. This model is a necessary step towards a foundation model trained on the entirety of Gaia data products, and provides a blueprint for future work with the upcoming Gaia Data Release 4.
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Astrophysics of Galaxies · Cross-listed from astro-ph.HE
Revealing the accretion disc structure in Changing State AGN: NGC1566
Huimei Wang, Chris Done, Riccardo Middei et al. (+1 more)
NGC1566 is a low mass ($\sim 6\times 10^6M_\odot$) Active Galactic
Nuclei (AGN) with unusual large amplitude variabilty in its
accretion flow. In the optical it cycles between recurring short bright episodes with strong blue/UV continuum and clear broad line emission, and a much weaker persistent level without strong broad lines, making it a repeating changing-state (CS) AGN. We re-analyse the intensive optical/UV and X-ray monitoring during the 2018 bright
flare, showing for the first time the corresponding
evolution of the (host
galaxy subtracted) optical/UV AGN spectrum as well as the X-ray emission. As seen in other CS-AGN, the strongest spectral
evolution is in a UV/soft X-ray component which likely disappears below $0.01L_{\rm Edd}$ while the hot corona and a redder optical/UV component show weaker variability. We show that the red optical emission is likely a composite of the intrinsic and reprocessed emission from the outer disc, together with diffuse continuum from the BLR, and discuss the different signatures predicted by this for continuum reverberation across the changing-state event. The historical lightcurves show repeated changing-state events tied to unusually large amplitude discrete
flares in the lightcurve. While these do not appear to be periodic, the behaviour does support previous suggestions that the
accretion flow is repeatedly perturbed, perhaps by an intermediate mass black hole companion.
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All authors Huimei Wang, Chris Done, Riccardo Middei, Xue-Bing Wu
Astrophysics of Galaxies · Cross-listed from astro-ph.IM
An X-ray Extremely wide-field Spectroscopic Surveyor (XESS, or "chess")
W. P. Maksym, M. Ulmer, S. Friedrich et al. (+20 more)
We propose an X-ray observatory, the X-ray Extremely wide-field Spectroscopic Surveyor (XESS, pronounced "Chess") to bring high energy resolution X-ray spectroscopy into the era of synoptic surveys and of time domain and multi-messenger astrophysics (TDAMM). Such an observatory is optimally suited to addressing key elements of the 2020 Decadal Survey on Astronomy and Astrophysics.
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All authors W. P. Maksym, M. Ulmer, S. Friedrich, F. Tombesi, R. Arcodia, S. P. Singam, S. Bongiorno, N. Thomas, M. Elvis, Ming Sun, John ZuHone, M. Lynne Saade, Philip Kaaret, Doug Swartz, Erin Hicks, Ming-Yi Lin, Pallavi Patil, Jimmy Irwin, Shrabani Kumar, Kirtan Dixit, Sudip Chakraborty, Andrea Gnarini, Steven Ehlert
Astrophysics of Galaxies · Cross-listed from astro-ph.CO
Testing Offsets Between Cluster-Scale Halos and BCGs in Strong Lensing Models Using the Jackknife Method
Sangjun Cha, Marceau Limousin and M. James Jee
Offsets between cluster-scale dark matter
halos and brightest cluster
galaxies (BCGs) inferred from strong
lensing (SL) models have been used to investigate cluster dynamics and dark matter physics. However, it is necessary to test whether these offsets are required by SL data themselves. We investigate whether allowing these offsets improves predictive accuracy and examine the effects on magnification, time-delay predictions, and critical curve positions. We evaluate lens models of Abell 370, RX J1347.5-1145, and MACS J0416.1-2403 using the jackknife method, which assesses predictions for source systems excluded from the lens reconstruction. Models are constructed with MrMARTIAN, which combines analytic mass profiles with a regularized grid that represents mass structure not captured by the profiles. We compare fixed and free
halo position models across regularization weights. The root mean square values averaged over excluded systems agree within bootstrap uncertainties, while the median paired differences remain close to zero across all three clusters and tested regularization weights. These results indicate comparable predictive accuracy between the fixed and free models. The total mass distributions remain broadly similar, although the magnitudes of fitted
halo offsets vary with regularization, showing that the mass decomposition is not unique. For these three clusters, offsets between BCGs and cluster-scale
halos in the lens models are not required by the SL data to improve predictive accuracy within the MrMARTIAN framework. The mass decomposition between the regularized grid and cluster-scale
halos is not uniquely determined. These findings limit physical interpretations based on fitted
halo positions alone. The model dependence of magnification and time-delay estimation can also affect the inferred intrinsic properties of high-
redshift sources or the Hubble constant.
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Astrophysics of Galaxies · Cross-listed from astro-ph.HE
Not So Heavy Metal I: Low Metallicity Enhances the Rate of high-redshift Superluminous Supernovae
Ben Margalit, Allison L. Strom, Cristina Andrade et al. (+4 more)
Type-I superluminous
supernovae (SLSNe) are extremely luminous stellar explosions originating from the core collapse of massive
stars. Unlike normal core-collapse
supernovae, however, SLSNe occur almost exclusively in metal-poor environments. As a result, their volumetric rate should not simply trace the
cosmic star-formation history, but instead evolve with the
metallicity distribution of
galaxies across
cosmic time. In this work, we introduce a new theoretical framework for modeling the volumetric rate of astrophysical sources as a function of
redshift and
metallicity. Our formalism combines
metallicity scaling relations, stellar-mass distribution functions, and
metallicity-dependent production efficiencies. Importantly, it also distinguishes between
metallicity measures based on O/H and Fe/H abundances. Applying our new formalism to SLSNe, we predict volumetric rates that are nearly an order of magnitude higher at $z \gtrsim 2$ compared to models in which the rate traces the
cosmic star-formation rate alone. This has direct implications on the detection prospects of high-$z$ SLSNe with the Vera C. Rubin Observatory and other time-domain surveys.
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All authors Ben Margalit, Allison L. Strom, Cristina Andrade, Michael W. Coughlin, Adam A. Miller, Steve Schulze, Ved G. Shah
Astrophysics of Galaxies
The orbital dynamics of the LMC and SMC about the Milky Way
Gurtina Besla and Nitya Kallivayalil
This review summarizes the changing observational and theoretical landscape that has led to rapid developments in our understanding of the orbital history of the Milky Way's most massive satellite
galaxies, the LMC and SMC. The determination of high precision center-of-mass proper motions for the Clouds and their environs, coupled with new insights into the structure of dark matter
halos from cosmological simulations, indicates that the Clouds are recent additions to the Milky Way's satellite system, where the LMC was sufficiently massive at infall to induce distortions in the Milky Way's dark matter
halo, and bring in satellites of its own. To gain insights into the orbital history of the Clouds it is, therefore, necessary to integrate orbits in a time evolving Milky Way and LMC potential. The proper motion measurements further indicate that the LMC and SMC have had a recent strong encounter with each other. This leaves open the impact of this encounter on their internal structures, and the degree of correspondence between their stellar, HI and dark matter centers. The choice of kinematic center in turn affects the center of mass proper motions; this is the biggest observational unknown, even in the high precision Gaia era. Given the expected mass loss of the SMC, the distortions it induces in the LMC
halo, and the recent LMC-SMC close encounter, understanding the orbits of objects about the LMC (including the SMC) and interpreting observational data of the Clouds requires full N-body simulations that are constrained by their present-day structure and kinematics.
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Astrophysics of Galaxies
LYRA: The formation and growth of nuclear star clusters in dwarf galaxies
Joaquin Sureda, Azadeh Fattahi, Sownak Bose et al. (+5 more)
Nuclear
star clusters (NSCs) are dense massive
star clusters ubiquitous in galactic centres across various mass regimes, present in up to $\sim30$ per cent of dwarf
galaxies with $M_\star<10^{7}\, \mathrm{M}_\odot$. Although their main growth pathways are well studied, there is still ongoing debate regarding their formation. We use the LYRA cosmological hydrodynamical simulations to study the formation and growth of NSCs in a sample of six dwarf
galaxies, where we identify NSCs with masses $M_\mathrm{NSC} \sim 10^4 - 10^6 \, \mathrm{M}_\odot$ in all
galaxies in our sample. The NSCs in our sample emerge at early times as a compact component, with the host
galaxy growing around them. This is consistent with a scenario in which NSCs are among the earliest structures to form in a
galaxy. We characterise the origin of the
stars that constitute the NSCs and explore the properties of the stellar populations in each of these channels. We find that most of the NSC mass originates from in-situ
star formation within the NSCs themselves. While this might appear at odds with current observations, the bulk of this
star formation occurs at early times, resulting in a significant population of old and metal-poor
stars, in agreement with an early NSC formation. We also identify
galaxy-
galaxy mergers as a significant contributor to the NSC mass, with usually one merger dominating this contribution. Our results highlight the complexity in the growth history of NSCs in dwarf
galaxies and highlight the importance of considering additional growth channels for NSCs in dwarfs
galaxies.
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All authors Joaquin Sureda, Azadeh Fattahi, Sownak Bose, Mariya Lyubenova, Jessica E. Doppel, Thales Gutcke, Katja Fahrion, Rüdiger Pakmor
Astrophysics of Galaxies
Discovery of the Lyman-$\alpha$ Forest in a Star-Forming Galaxy at $z \approx 7.57$: Implications for the Timing and Topology of Cosmic Reionization
Jakob M. Helton, Joris Witstok, Marta Laska et al. (+15 more)
The escape of ionizing
photons from
galaxies during the Epoch of Reionization is often inferred indirectly because the intervening neutral hydrogen in the intergalactic medium (IGM) is expected to absorb all flux blueward of Lyman-$\alpha$ at these
redshifts. However, in this work, we report the significant detection ($\approx7\sigma$) of flux blueward of Ly$\alpha$ in a massive ($M_{\ast}\approx10^{9.1}\ M_{\odot}$)
star-forming
galaxy at $z\approx7.57$, JADES-GS-z7-LAF, using JWST/NIRSpec PRISM spectroscopy. We independently confirm this detection of the Ly$\alpha$ forest (LAF) using JWST/NIRCam F090W imaging ($\approx10\sigma$). The blueward flux in F090W is spatially coincident with the
galaxy and emerges $\approx0.4$ pkpc from its UV centroid at $\lambda_{\mathrm{rest}}\approx1500\ \mathrm{\mathring{A}}$. We find no evidence for a foreground interloper producing the observed flux, although we cannot formally reject this interpretation with the existing data. The transmitted flux implies an extraordinarily transparent sightline ($x_{\mathrm{HI}}\ll0.1\%$) through the IGM at $z \approx 5.5-7.5$, a sightline that is spatially and kinematically coincident with numerous high-
redshift galaxy overdensities, which possibly explains the emergence of this flux. We observe a smooth and gradual turnover around the Ly$\alpha$ break that is either consistent with an extreme damping-wing ($N_{\mathrm{HI}}\approx10^{23.3}\ \mathrm{cm}^{-2}$) or a strong nebular continuum (contributing $\approx60-70\%$ of the flux at $\lambda_{\mathrm{rest}}=1500\ \mathrm{\mathring{A}}$). JADES-GS-z7-LAF is far more luminous ($M_{\mathrm{UV}}\approx-21.5$, similar to GN-z11) than the faint sources usually invoked as the drivers of
cosmic reionization. If such systems are common in the early Universe, massive
galaxies may contribute more to the ionizing
photon budget than suggested by other indirect constraints.
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All authors Jakob M. Helton, Joris Witstok, Marta Laska, Kevin N. Hainline, Nikko J. Cleri, Francesco D'Eugenio, Ignas Juodžbalis, Nimisha Kumari, Joel Leja, Sandro Tacchella, Rachana Bhatawdekar, Andrew J. Bunker, Daniel J. Eisenstein, Zhiyuan Ji, Benjamin D. Johnson, Pierluigi Rinaldi, Brant E. Robertson, Christopher N. A. Willmer
Astrophysics of Galaxies
Detecting HI Self-Absorption using Neural Networks
Eric G. M. Muller, Naomi M. McClure-Griffiths, Hiep Nguyen et al. (+5 more)
Cold atomic hydrogen plays a crucial role in the life cycle of interstellar gas. It serves as the intermediary phase in the condensation and cooling processes that bridge the warm diffuse gas in and around
galaxies, and the cold molecular gas that drives
star formation. HI self-absorption in the 21-cm emission line is the most direct observational tracer of cold HI gas that does not require a continuum background source, yet its systematic extraction remains a long-standing challenge. Existing methods of self-absorption identification rely on subjective by-eye inspection or modelling of the underlying emission, making repeatable, thorough, and large-scale applications difficult. We present a lightweight convolutional neural network designed to detect self-absorption features and infer their velocities via a post-hoc process, without assumptions about the underlying emission or the use of ancillary data. Trained on synthetic emission spectra, the neural network achieves 96.5 per cent accuracy, 96.0 per cent precision, and 97.0 per cent recall on held-out synthetic data. Applied to observed 21-cm emission data from the Riegel–Crutcher cloud and giant molecular filament regions towards the Galactic Plane, the network recovers the spatial distributions and velocities of known self-absorption structures when compared to previous analyses and ancillary 13CO emission data. Crucially, the neural network is computationally efficient, processing detections for ~15,000 spectra per second on a single consumer laptop GPU, enabling real-time cold HI detection at the data rates anticipated by next-generation facilities such as the Square Kilometre Array.
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All authors Eric G. M. Muller, Naomi M. McClure-Griffiths, Hiep Nguyen, Matthew J. Alger, Frances Buckland-Willis, J. R. Dawson, Min-Young Lee, Antoine Marchal
Astrophysics of Galaxies · Cross-listed from astro-ph.EP
Constraining exoplanet population parameters with Kepler and simulation-based inference
Chloé Padois, Friedrich Anders and Daniel del Ser
In the context of the rapidly growing field of galactic
exoplanet population studies, we present an
exoplanet simulator capable of generating synthetic populations for millions of
stars in a few seconds (Padois et al., 2025). Our framework combines observed
exoplanet detections with the latest planetary formation models, incorporating dependencies between host
star properties and
planet occurrence rates, orbital period distributions, and other key demographic features. However, many model parameters remain uncertain and model-dependent. To constrain some of the most critical ones, we couple our simulator with simulation-based inference (SBI): we define a set of 44 free parameters describing the population of different
planet types (occurrence rates, mass-period distribution, mass-radius relation, etc.), run millions of simulations sampling from broad prior distributions, simulate their detectability by Kepler, and train a machine-learning
algorithm to learn the relationships between input parameters and the resulting "observed" synthetic populations. The best-fit parameters are then inferred by comparing model outputs to real observations, for which we adopt the Kepler confirmed
planet catalogue as our reference
dataset, since it provides the largest homogeneous sample from a single facility. We present preliminary results for the
planet occurrence rate as a function of stellar mass and
metallicity, across different
planet types, along with constraints on several key simulation parameters such as the orbital period distribution and the inclination dispersion within planetary systems. These refined parameters enable us to refine our yield predictions for upcoming
exoplanet detection missions, including PLATO, Roman, and HAYDN.
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Astrophysics of Galaxies
Torsionally excited methanol in massive young stellar objects: The role of the mid-IR radiation field
C. Sanna, S. Leurini, A. Giannetti et al. (+9 more)
Observing the earliest stages of high-mass
star formation in the mid-infrared (mid-IR) is challenging because the extinction is high and the resolution limited. Millimeter vibrationally and torsionally excited transitions of several molecules have been proposed as indirect probes of local mid-IR radiation fields around young stellar objects (YSOs). We investigate the excitation and spatial distribution of torsionally excited methanol ($\mathrm{CH_3OH}$) in 12 high-mass
star-forming clumps in different evolutionary stages, assessing their potential as tracers of the mid-IR luminosity of embedded protostars. We analyzed rotational transitions of methanol within the same torsionally excited states $v_\mathrm{t}$$\geq$1 in the Atacama Large Millimeter/submillimeter Array (ALMA) 890 $\mathrm{\mu m}$ observations and compared them with Spitzer 24 $\mathrm{\mu m}$ data by plotting line luminosities normalized by methanol abundance against mid-IR luminosities. The torsionally excited methanol emission is generally compact and systematically coincident with ALMA dust continuum peaks and 24 $\mathrm{\mu m}$ emission, even in faint sources. The only clump without an IR counterpart also shows no $v_\mathrm{t}$$\geq$1 emission, supporting radiative pumping as the dominant excitation mechanism. We found a promising power-law trend between $v_\mathrm{t}$$\geq$1 methanol lines and 24 $\mathrm{\mu m}$ luminosities, largely independent of the methanol abundance. $\mathrm{CH_3OH}$ $v_\mathrm{t}$$\geq$1 transitions appear to be promising tracers of local mid-IR radiation fields of embedded protostars, providing core-scale information even in highly extincted regions. As a pilot study, our results suggest that extending our study to a larger statistical sample is crucial for testing and improving this method.
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All authors C. Sanna, S. Leurini, A. Giannetti, E. Schisano, L. Testi, S. Molinari, J. S. Urquhart, T. Pillai, F. Massi, K. Immer, E. Molinari, S. Casu
Astrophysics of Galaxies
A Full-Sky SPHEREx Map of Integrated 3.3 and 3.4 {\mu}m PAH Emission
Roke Cepeda-Arroita, Clive Dickinson, J. Alberto Rubiño-Martín et al. (+4 more)
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the interstellar medium and are among its smallest carbonaceous grains. Their infrared emission bands trace this small-grain population together with the interstellar radiation field that excites it, and are widely used to diagnose photodissociation regions, dust processing and
star formation. We present full-sky maps of the integrated radiance of the 3.3 $\mu$m aromatic C-H stretch and the adjacent 3.4-3.5 $\mu$m aliphatic complex, from SPHEREx QR2 Level-2 data. Existing all-sky PAH tracers are broadband, so the band emission can only be inferred as an excess over stellar and continuum emission; SPHEREx samples the spectrum finely enough for the bands to be fitted directly. We mask flagged detector pixels, subtract the per-pixel zodiacal-light model, subtract point sources with an empirically derived PSF, and coadd the results into inverse-variance-weighted HEALPix maps at 2.6' FWHM and Nside=4096 in 102 narrowband channels across Detector 4 (2.42-3.82 $\mu$m). At every sky pixel we fit a continuum and the two bands. The combined band radiance is the primary product; its decomposition into the aromatic and aliphatic components is released alongside it as an estimate, with its modelling systematic stated. These are the first full-sky maps of PAH band emission, resolving the 3.3 and 3.4-3.5 $\mu$m bands spectrally, and the first full-sky PAH maps from SPHEREx to be released. Because the 3.3 $\mu$m band is emitted preferentially by the smallest PAHs, the maps trace directly a grain population, including the candidate carriers of anomalous microwave emission, that broadband PAH proxies reach only indirectly. The maps and their associated products, including a reliability mask, are publicly available with an explanatory supplement at https://research.iac.es/proyecto/radioforegroundsplus/pages/data-products/spherex-pahs.php.
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All authors Roke Cepeda-Arroita, Clive Dickinson, J. Alberto Rubiño-Martín, Ricardo T. Génova-Santos, Gabriel A. Hoerning, Stuart E. Harper, Debabrata Adak
Astrophysics of Galaxies
Thermally irreversible sulfur chemisorption on silicate grains as a major sulfur reservoir in molecular clouds
Ni-En Sie, Masashi Tsuge, Yasuhiro Oba et al. (+3 more)
Sulfur (S) chemistry in the interstellar medium remains poorly constrained due to the longstanding "missing sulfur" problem, where a significant fraction of
cosmic sulfur in molecular clouds remains unidentified. To gain a comprehensive understanding of S chemistry in the interstellar medium, its behavior on interstellar dust grains must be clarified. Here, we experimentally investigated the surface elementary processes of S atoms under conditions mimicking interstellar molecular clouds. Our in-situ
laser-based detection method enabled the direct tracking of S atoms adsorbed on astrophysically relevant silicate substrates and amorphous solid water (ASW). We found that sulfur atoms strongly chemisorbs onto silicate surfaces and remains bound even after ASW sublimation, rendering it observationally invisible. An astrochemical model coupled with these results suggests that at least 10 percent of the total sulfur budget in molecular clouds must be locked onto silicate dust grains. Our results identify sulfur chemisorption on silicate as a key mechanism driving sulfur depletion and provide a physical explanation for the missing sulfur problem.
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All authors Ni-En Sie, Masashi Tsuge, Yasuhiro Oba, Germán Molpeceres, Kenji Furuya, Naoki Watanabe
Astrophysics of Galaxies · Cross-listed from astro-ph.HE
X-ray measurements of the elemental abundances for the diffuse emission in the nuclear starburst galaxy NGC 3079
Jiejia Liu, Junjie Mao, Shuinai Zhang et al. (+3 more)
Outflows driven by feedback leave imprints on a
galaxy's diffuse X-ray emission. Elemental abundances provide key diagnostics of feedback-driven chemical enrichment. We present a spectroscopic study of the diffuse X-ray emission in NGC 3079 using XMM-Newton RGS and EPIC, focusing on the nuclear region and the extended galactic-scale superbubble (GSB). We analyzed the high-resolution RGS spectrum of the central $\sim4~\rm kpc$ region, encompassing the $\sim1~\rm kpc$ nuclear superbubble (NSB), and the EPIC spectrum of the GSB out to $5'~(\sim25~\rm kpc)$. The nuclear spectrum is best described by a multi-temperature thermal-
plasma model plus a charge-exchange (CX) component, which contributes approximately $13\%$ of the total observed energy flux in the $0.2-2~\rm keV$ band. The best-fit O/Fe and Ne/Fe ratios are $0.47$ and $0.77$ in solar units. Comparing these ratios with IMF-weighted core-collapse
supernova (SNcc) yields gives an upper progenitor-mass cutoff of $M_{\rm u}\simeq13-15~M_{\odot}$ for pure SNcc enrichment. For the best-fit spectral model, including an SNIa contribution increases the inferred cutoff, but its $1\sigma$ upper limit remains below $25~M_\odot$ for SNIa fractions up to $10\%$ within the adopted yield models. The characteristic ages of the NSB and GSB are $0.92^{+0.39}_{-0.46}~\rm Myr$ and $29.6^{+1.6}_{-2.9}~\rm Myr$, respectively, suggesting episodic feedback in NGC 3079.
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All authors Jiejia Liu, Junjie Mao, Shuinai Zhang, Guan-Fu Liu, Rui Huang, Wei Cui
Astrophysics of Galaxies
GA-NIFS: sRMS, a new method for disentangling resolved and unresolved emission in integral field spectroscopy. Application to distant quasars
Michele Perna, Santiago Arribas, Carlota Prieto-Jiménez et al. (+28 more)
The interpretation of AGN emission-line profiles in type1 AGN is often complicated by the dominance of bright, spatially unresolved nuclear continuum and broad-line region (BLR) emission over narrower and blended components from the narrow-line region (NLR) and the host
galaxy. This remains challenging even with integral-field spectroscopy (IFS), as the relevant spatial variations can occur on scales smaller than the angular resolution, particularly in the compact host of distant AGN. We introduce the spatial root-mean-square (sRMS) technique, a new approach to analyse single-epoch IFS that uses the spatial variance of spectra extracted from partially overlapping apertures to isolate off-nuclear emission of high-z BL-AGN, and investigate whether the resulting kinematic information can improve the decomposition of their integrated spectra. We construct sRMS spectra from ensembles of overlapping apertures centred on the unresolved
nucleus. Emission that is spatially invariant on the scales probed by the apertures is consequently suppressed, whereas spatially varying emission is retained. We apply the procedure to JWST/NIRSpec data of two z~6.5 QSOs. We model the resulting sRMS spectra with multiple Gaussian components to determine the kinematics of the spatially varying emission, and use these kinematic constraints to model the integrated spectra. The sRMS technique identifies spatially varying narrow-line emission on scales up to ~5x smaller than the NIRSpec PSF and provides robust constraints on the kinematics of individual kinematic components. Imposing these kinematic constraints on the integrated-spectrum fit reduces significantly the degeneracy of multi-component decompositions. Simulations further demonstrate the potential of the method to detect spatially offset BLR emission from close dual BL-AGN, down to projected separations of ~200 pc at z~6.5 for a BLR flux ratio of ~10.
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All authors Michele Perna, Santiago Arribas, Carlota Prieto-Jiménez, Isabella Lamperti, Lorenzo Ulivi, Hannah Übler, Giovanni Cresci, Bruno Rodríguez Del Pino, Torsten Böker, Andrew J. Bunker, Stéphane Charlot, Roberto Maiolino, Chris J. Willott, Ivan Delvecchio, Elena Bertola, Madeline A. Marshall, Eleonora Parlanti, Pablo G. Pérez-González, Giacomo Venturi, Sandra Zamora, Filippo Mannucci, Quirino D'Amato, Alessandra De Rosa, Ismael García-Bernete, Alessandro Marconi, Miguel Pereira-Santaella, Fabio Rigamonti, Martina Scialpi, Paola Severgnini, Cristian Vignali, Maria Vittoria Zanchettin
Astrophysics of Galaxies · Cross-listed from astro-ph.SR
Abundance analysis of three new extremely metal-poor stars, including one CEMP-s star
P. François, T. Suda, S. Wanajo et al. (+5 more)
We report a detailed abundance analysis of three extremely metal-poor (EMP)
stars thanks to spectra obtained with the high-dispersion spectrograph (HDS) at the Subaru
telescope. The aim is to observe a sample of EMP candidate
stars selected from the Sloan Digital Sky Survey (SDSS) and determine their detailed chemical composition. High-resolution spectra of three faint turn-off
stars using HDS on the Subaru
telescope were acquired.We used standard 1D models to compute the abundances of several elements (Li, C, Mg, Ca, Sr, and Ba). The
stars we analysed have a
metallicity [Fe/H] of between -3.02 and -3.57 dex. We also measured accurate radial velocities that, coupled with the Gaia astrometric data, allowed us to compute actions and Galactic orbits for the
stars. Our analysis confirms that the
stars are genuine EMP
stars. One of them (SDSS J074238.68 +470537.0) can be classified as a CEMP-s
star with the highest [Mg/Fe] ratio ever measured in a turn-off CEMP-s
star with [Mg/Fe] = 1.85 dex. For the
star SDSS J012630.30+073029.3 ([Fe/H]= -3.02 dex), we have a clear detection of lithium with A(Li) = 2.05. Kinematically, SDSS J214340.08-002835.5 is a thick-disc
star, while the other two belong to the
halo and are candidate members of the Gaia- Sausage-Enceladus.
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All authors P. François, T. Suda, S. Wanajo, E. Caffau, P. Bonifacio, W. Aoki, S. Yamada, M. Y. Fujimoto
Astrophysics of Galaxies
Fooled by mass? Recovering the $\Gamma-\lambda_{Edd}$ relation of quasars from their X-ray variability
Matilde Signorini, Andrea Sacchi, Bartolomeo Trefoloni et al. (+7 more)
We measure the relation between the X-ray
photon index $\Gamma$ and the Eddington ratio $\lambda_{Edd}$ in unobscured type-1
quasars, using as parent sample the cross-match of the SDSS DR16Q catalogue with the 4XMM-DR14 serendipitous catalogue. After cleaning the sample of potential observational biases, we obtain 7835 objects, one order of magnitude larger than most previous analyses in the literature. A single regression of $\Gamma$ against $\log\lambda_{Edd}$, with single-epoch virial black-hole masses, returns slopes that depend on the mass indicator (H$\beta$, MgII, CIV) and on the bolometric correction, and that are generally flat. We interpret this as regression dilution: the systematic uncertainty on virial masses is much larger than the intrinsic spread of $\lambda_{Edd}$ in SDSS
quasars. We therefore introduce a different approach, which removes the black-hole mass from the problem. For
quasars observed by XMM-Newton at multiple epochs, the mass of each object is fixed, and changes in its X-ray luminosity trace changes in its
accretion state. We fit the $\Gamma$-$\log(L_{2keV})$ relation of each object (for a sample of N=893) and combine the per-object posteriors. This recovers the mean response of the population $a_X = 0.35\pm0.03$, which steepens to $\approx0.43$ when only epochs with precisely measured
photon indices are used. Translated to the Eddington ratio, this corresponds to $a_\lambda\approx0.20$-0.25, depending on the choice of bolometric correction and on the LX-LUV slope. The $\Gamma$–$\lambda_{Edd}$ relation therefore exists, but it can be uncovered only by exploiting the variability of individual sources, which removes the black-hole mass from the problem. Moreover, its shallowness implies that the differences in Eddington ratio, as currently measured, cannot by themselves account for the variety of
photon indices observed among unobscured
quasars.
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All authors Matilde Signorini, Andrea Sacchi, Bartolomeo Trefoloni, Matteo Guainazzi, Elisabeta Lusso, Emanuele Nardini, Chiara Niccolai, Federica Ricci, Anastasia Shlentsova, Mateusz Rałowski
Astrophysics of Galaxies
Caught in the act: diffuse stellar and Ly$\alpha$ emission around a halo-less quasar in the assembling cluster CARLA J0800+4029 at z=2
Sofia G. Gallego, Simona Mei, Emanuele Daddi et al. (+3 more)
Extended Ly$\alpha$ emission is commonly detected around luminous
quasars at $z\sim2$-3 and traces cold gas in the circumgalactic environment of the AGN. Together with the spatial distribution of
galaxies, Ly$\alpha$ probes gas and
galaxy assembly in high-
redshift overdensities. We use deep KCWI wide-field spectroscopy and HST/F140W imaging to investigate the assembling cluster CARLA J0800+4029 at $z=1.986\pm0.014$. No robust extended Ly$\alpha$ emission is detected at the
radio-loud
quasar position. Instead, the dominant Ly$\alpha$ emission is offset from the AGN and coincides with a disturbed structure composed of
galaxies, tidal features, and diffuse intra-
halo light (IHL). The detected structure has $L_{\rm Ly\alpha}=1.42\times10^{43}$ erg/s and reaches surface-brightness levels of $\sim10^{-17}$ erg/s/cm$^2$/arcsec$^2$. At the
quasar position, a matched $3\sigma$ limit gives $L_{\rm Ly\alpha}<4.20\times10^{42}$ erg/s, a factor of $\sim3.4$ below the detected offset emission and among the most stringent constraints at similar
redshift. The Ly$\alpha$ emission is dominated by one extended region near systemic velocity, with FWHM $\sim300$-500 km/s. The associated tidal structure has an IHL fraction of 18.8%, and contains a spatially coherent absorption-like decrement at $\sim+1000$ km/s. The offset and
alignment between Ly$\alpha$ emission and IHL suggest that gas and
stars have been redistributed together during assembly. The lack of a comparable Ly$\alpha$
halo around the
quasar further suggests that gas in the immediate AGN environment is ionized, depleted, or suppressed, while the offset region remains favorable for Ly$\alpha$ emission. CARLA J0800+4029 reveals baryon redistribution during cluster assembly, with the dominant observable Ly$\alpha$ reservoir decoupled from the central AGN and linked to ongoing tidal assembly.
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All authors Sofia G. Gallego, Simona Mei, Emanuele Daddi, Gaël Noirot, Dominika Wylezalek, R. Michael Rich
Astrophysics of Galaxies
The ALPINE-CRISTAL-JWST Survey: Investigating the role of interstellar dust, gas and stars in high-z galaxies at kpc-scales
F. Lopez, M. Relano, I. De Looze et al. (+37 more)
A comprehensive understanding of
galaxy evolution requires a detailed analysis of gas and dust, their distribution, and
evolution within
galaxies. We analyse spatially resolved (~kpc) rest-frame [CII] and dust continuum ALMA observations together with JWST/NIRSpec IFU data of a sample of
galaxies at z~4-5. We focus on deriving the spatial distributions of atomic and molecular gas masses, dust and stellar masses,
star formation rates (SFR), and
metallicity. The oxygen abundance maps have values in the range of 12+log(O/H)~8.1-8.3 with variations of the order of 1dex within the same
galaxy. The calibration used in this study to estimate the atomic gas mass in our
galaxies seems to overestimate the atomic gas mass surface densities up to 1-2 orders of magnitude. However, a calibration based on a spatially resolved [CII] conversion factor gives a more robust estimation of the total gas mass.
Galaxies exhibiting signatures of strong outflows have lower dust-to-stellar surface mass density ratio and lower gas mass fractions than the
galaxies with no outflow signatures. While the latter is consistent with these
galaxies ejecting part of their gas reservoir to the circumgalactic medium, the low dust-to-stellar surface mass density ratios also suggest that part of the dust content is expelled outside the
galaxy, which reinforces previous theoretical suggestions of dust removal by stellar feedback or radiation pressure to explain the high UV luminosities in
galaxies at very high-
redshifts. Some
galaxies of our sample have almost an order of magnitude higher dust-to-gas and dust-to-stellar surface mass density ratio than
galaxies in the local Universe, suggesting that a large dust reservoir has been built up already at time scales of ~1 Gyr in these
galaxies.
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All authors F. Lopez, M. Relano, I. De Looze, A. L. Faisst, R. Herrera-Camus, R. A. Jorgenson, E. Pérez-Montero, M. Palla, C. Accard, R. O. Amorin, M. Aravena, R. J. Assef, A. J. Battisti, M. Boquien, E. da Cunha, P. Dam, R. L. Davies, M. Dessauges-Zavadsky, A. Ferrara, S. Fujimoto, M. Ginolfi, N. Gutierrez-Vera, A. Hadi, E. Ibar, H. Inami, A. M. Koekemoer, L. L. Lee, J. Li, J. Molina, A. Nanni, D. Narayanan, F. Pozzi, F. Rizzo, M. Romano, D. B. Sanders, P. Sawant, L. Vallini, S. A. van der Giessen, V. Villanueva, G. Zamorani
Astrophysics of Galaxies · Cross-listed from gr-qc
The Irreversible Depletion of Dark Matter Spikes by Extreme-Mass-Ratio Inspirals
Charlie Sharpe, Yonadav Barry Ginat, Thomas F. M. Spieksma et al. (+2 more)
Dense dark matter spikes around massive black holes (MBHs) have been widely predicted to produce gravitational-wave dephasing in extreme-mass-ratio inspirals (EMRIs) that are potentially observable by LISA. We show that EMRIs, the very objects used to probe these spikes, also destroy them. Combining Fokker-Planck models of nuclear
star clusters with post-Newtonian three-body simulations of EMRI-dark matter encounters, we demonstrate that repeated gravitational slingshots irreversibly eject dark matter particles from the cluster's loss cone over gigayear time-scales. For MBHs at $z = 3$ with masses $\lesssim 10^5 \,M_\odot$, even conservative EMRI rates of $\mathcal{O}(1-10) \, \mathrm{Gyr}^{-1}$ suffice to deplete the spike density by orders of magnitude; for more realistic rates of $\mathcal{O}(100-300) \, \mathrm{Gyr}^{-1}$, the mass range extends to $\lesssim 10^6 \,M_\odot$. As a result, the gravitational-wave dephasing expected from such systems is greatly reduced, narrowing the prospects of detecting DM through this channel. Only heavy, high-
redshift systems with sufficiently low EMRI rates – for example, a $\sim 10^6 \,M_\odot$ MBH at $z \gtrsim 5$ with $\lesssim 100$ EMRIs per Gyr – can induce dephasing that exceeds one radian.
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All authors Charlie Sharpe, Yonadav Barry Ginat, Thomas F. M. Spieksma, Alexander Heger, Bence Kocsis
Astrophysics of Galaxies
MEGATRON: Dwarf Galaxy Quenching in the Epoch of Reionization
David Attard, Ilian T. Iliev, Martin P. Rey et al. (+3 more)
Low-mass
galaxies during the Epoch of Reionization are expected to form
stars in short bursts separated by periods of inactivity, but what regulates this cycle, and how sensitive it is to the modelling of stellar feedback, remains unclear. We use the MEGATRON high-
redshift zoom simulation suite, in which four
star-formation and stellar-feedback prescriptions are evolved from identical initial conditions, to study the regulation of stellar mass growth in
galaxies with $M_{*} \sim 10^{4} - 10^{8} M_{\odot}$ at $z = 8.5$. We classify
galaxies as
Star-Forming, Mini-Quenched (no significant
star formation over the last 10 Myr), or Quenched (no significant
star formation over the last 100 Myr). The feedback prescription controls both how often
galaxies are quiescent and how this depends on mass. Models with stronger or more clustered feedback yield larger quiescent fractions compared to the fiducial and Varying IMF models. Duty cycles at fixed mass also differ by factors of several between models. The cold gas profiles of Quenched
galaxies are consistent with two physically distinct modes of quenching: mechanical gas evacuation, producing compact, cold gas-poor systems, and thermodynamic suppression, retaining a cold but
star-formation-inactive reservoir. At these masses, quiescent
galaxies fall below un-lensed JWST/NIRCam detection limits, whereas
star-forming
galaxies of the same mass do not, and consequently flux-limited samples will be biased towards active phases. Measuring the quiescent fraction as a function of stellar mass in
lensing fields would provide a direct test of stellar-feedback models at
Cosmic Dawn.
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All authors David Attard, Ilian T. Iliev, Martin P. Rey, Harley Katz, Corentin Cadiou, Nicholas Choustikov
Astrophysics of Galaxies · Cross-listed from astro-ph.EP
Detecting Extragalactic Exoplanets With Fast Radio Burst Nanolensing
Kenneth F. Olibrice and Dylan L. Jow
Fast
Radio Bursts (FRBs) are spatially and temporally compact sources at cosmological distances. As background sources, they will be uniquely sensitive to the gravitational
lensing of
exoplanets outside of our own
galaxy. We present a method to detect extragalactic
exoplanets using planetary echo nanolensing-periodic, nanosecond-scale variations in the relative time of arrival (ToA) between an initial FRB and its microlensed echo as the
planet orbits its host
star. For a simple binary lens model, we demonstrate that measuring the amplitude and period of these ToA fluctuations enables a determination of the
exoplanet mass and orbital parameters. FRBs will be most sensitive to echo nanolensing by lenses within ten megaparsecs of the Milky Way as well as within ten megaparsecs of the FRB host, opening the door to detections of
planets at a range of
redshifts. We estimate that at least one in a million FRBs will exhibit this phenomenon (i.e. an optical depth of $\tau_l = 10^{-6}$). While current burst rates and low repeating-FRB fractions make a detection challenging in the immediate term, upcoming high-volume surveys and next-generation arrays (such as the SKA Phase 2) will bring the unambiguous detection of extragalactic
exoplanets across cosmological
redshifts into possibility.
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Astrophysics of Galaxies · Cross-listed from astro-ph.IM
LUMA: A CNN for Strong Gravitational Lens Searches in Astronomical Imaging
Giovanni Vincenzo Donatiello, Achille A. Nucita, Francesco De Paolis et al. (+2 more)
We present LUMA, a convolutional neural network (CNN) pipeline for the automated detection of strong gravitational lenses in simulated astronomical imaging. The method combines a physically motivated preprocessing stage, which enhances faint arc and ring features, with a compact three-block CNN trained using class reweighting and modern learning-rate scheduling. On simulated data, the model reaches test accuracies of about $96$% and receiver operating characteristic (ROC) area-under-the-curve (AUC) values of $\simeq 0.99$ for the non-trivial classes, while confusion-
matrix analysis shows high completeness and purity for lens candidates. These results demonstrate that relatively lightweight CNN architectures can provide a competitive baseline for strong-lens searches, and they motivate future extensions toward real survey images and
transformer-based models.
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All authors Giovanni Vincenzo Donatiello, Achille A. Nucita, Francesco De Paolis, Antonio Franco, Francesco Strafella