arXiv subjects

Swayamtrupta Panda

Publications and source records attributed to Swayamtrupta Panda.

At least 37 records · Page 2Linked to original sources

arXiv2025

Connecting disc-corona physics and ionised outflows in AGN in the 2040s

We outline a science case for next-generation wide-field spectroscopic surveys aimed at connecting the physics of the accretion disc and X-ray corona in active galactic nuclei (AGN) with the properties of their nebular regions and circumgalactic medium (CGM). We focus on the non-linear Lx-Luv relation and on deviations from this canonical coupling encoded in $Δα_{OX}$, the offset of the optical-to-X-ray index from the mean relation, and propose to use broad and narrow line emission and CGM nebulae as calorimeters of the ionising SED to trace different accretion "states". We propose an observational strategy based on rest-frame UV/optical spectroscopy of $\sim 10^{4}-10^{5}$ AGN, a time-domain reverberation-mapping tier for a well-defined subsample, coordinated X-ray coverage, and wide-field IFU mapping of CGM emission (including H$α$ and Ly$α$). From these goals we derive requirements for a future ESO facility in the 2040s: a dedicated, wide-field, high-multiplex optical-NIR spectroscopic telescope with time-domain flexibility and arcmin-scale IFU capability.

astro-ph.IM↗

arXiv2025

The evolution of obscured AGN across cosmic time -- A large quasar survey for the 2040s

We propose a large quasar demographic optical multi-object spectroscopic (MOS) survey targeting over 50 million AGN candidates up to the highest redshifts possible in the optical (z~6.5), with repeat visits, using a variety of selection criteria available by 2040. A large MOS survey combining all AGN selection methods is the only way to unify a diverse range of different obscured AGN populations within a single, variability- and spectroscopy-based framework, rather than as disjoint classes selected by different methods.

astro-ph.GA↗

arXiv2025

Galaxy evolution in compact groups - III. Structural analysis of galaxies and dynamical state of non-isolated compact groups

Compact Groups (CGs) of galaxies are dense systems where projected separations are comparable to their optical diameters. A subset - non-isolated CGs - are embedded within major structures. Using multi-band S-PLUS data, we analyse galaxies in 122 non-isolated CGs within more massive systems such as larger groups and clusters. We compare them to galaxies in the host structures, hereafter surrounding group galaxies. Structural parameters were obtained with MorphoPLUS, a pipeline for multi-wavelength Sérsic profile fitting. Dividing galaxies into early (ETG), transition, or late types (LTG), we find: (1) Non-isolated CGs host higher quenched fractions and more ETGs, especially for stellar masses $\log(M/M_\odot) > 10.2$, than surrounding groups. (2) Sérsic indices increase with wavelength for all morphological types in both environments, whereas effective radii show a stronger morphology-dependent behaviour - ETGs become more compact towards redder bands, while LTGs exhibit flatter $Re(λ)$ trends. Environmental differences remain weak, with only a modest enhancement of the gradients for ETGs in non-isolated CGs. (3) Transition galaxies in CGs show a concentrated $R_e$-$n$ distribution and faint-end bimodality, consistent with ongoing morphological transformation absent in surrounding groups. (4) Phase-space analysis indicates that some CGs in clusters are projection artefacts, while others are genuine dense systems at various infall stages, from recent arrivals to ancient remnants. These results show that galaxies in non-isolated CGs follow distinct evolutionary paths compared to their surrounding groups galaxies, suggesting that the compact configuration plays a unique role beyond the influence of the larger-scale environment.

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arXiv2025

Spectroscopic Alerts for the Time-Domain Era

Time-domain astronomy is entering an era of unprecedented discovery driven by wide-field, high-cadence surveys such as LSST, Roman, Euclid, SKA, and PLATO. While some of these facilities will generate enormous photometric alert streams, the physical interpretation of variability and transients often requires spectroscopy, which encodes changes in ionisation state, kinematics, and accretion that are inaccessible to photometry alone. A critical gap is therefore emerging: next-generation surveys may produce up to $\sim10^9$ alerts per year, whereas global spectroscopic follow-up is limited to only $\sim10^4$--$10^5$ transient spectra annually. We present the concept of spectroscopic alerts: real-time notifications triggered by significant spectral evolution, enabling spectroscopy to act as a discovery channel rather than solely as follow-up. We outline the key science cases enabled by this capability and describe the instrumental and operational requirements of a wide-field, highly multiplexed spectroscopic facility capable of delivering real-time spectral discovery for 2040s time-domain and multi-messenger astronomy.

astro-ph.IM↗

arXiv2025

HALO I: Photometric continuum reverberation mapping of Fairall 9

We investigate the origin of inter-band continuum time delays in active galactic nuclei (AGNs) to study the structure and properties of their accretion disks. We aim to measure the inter-band continuum time delays through photometric monitoring of Seyfert galaxy Fairall 9 to construct the lag-spectrum. Additionally, we explain the observed features in the Fairall 9 lag-spectrum and discuss the potential drivers behind them, based on our newly collected data from the Obserwatorium Cerro Murphy (OCM) telescope. We initiated a long-term, continuous AGN photometric monitoring program in 2024, titled 'Hubble constant constraints through AGN Light curve Observations' (HALO) using intermediate and broad band filters. Here, we present the first results from HALO, focusing on photometric light curves and continuum time-delay measurements for Fairall 9. To complement these observations and extend the wavelength coverage of the lag-spectrum, we also reanalyzed archival Swift light curves and spectroscopic data available in the literature. Using HALO and Swift light curves, we measured inter-band continuum delays to construct the lag-spectrum of Fairall 9. Excess lags appear in the $u$ and $U$ bands (Balmer continuum contamination) and in the $I$ band (Paschen jump/dust emission from the torus). Overall, the lag-spectrum deviates significantly from standard disk model predictions. We find that inter-band delays deviate from the power-law, $τ_λ \propto λ^β$ due to BLR scattering, reprocessing, and dust contributions at longer wavelengths. Power-law fits are therefore not well suited for characterizing the nature of the time delays.

astro-ph.GA↗

arXiv2025

Predicting Quasar Counts Detectable in the LSST Survey

The Legacy Survey of Space and Time (LSST), being conducted by the Vera C. Rubin Observatory, is a wide-field multi-band survey that will revolutionize our understanding of extragalactic sources through its unprecedented combination of area and depth. While the LSST survey strategy is still being finalized, the Rubin Observatory team has generated a series of survey simulations using the LSST Operations Simulator to explore the optimal survey strategy that best accommodates the majority of scientific goals. In this study, we utilize the latest simulated data to predict the number of detectable quasars by LSST in each band and evaluate the impact of different survey strategies. We find that the number of quasars and lower luminosity AGNs detected in the baseline strategy (v4.3.1) in the redshift range z=0.3-6.7 will be highest in the i-band and lowest in the u-band. Over 70% of quasars are expected to be detected within the first year in all bands, as LSST will have already reached the break of the luminosity function at most redshifts. With a limiting magnitude of 25.7 mag, we expect to detect 184 million AGNs in the z-band over the 10-year survey, with quasars constituting only 6% of the total AGNs in each band. This arises because, considering that the luminosities of most low-luminosity AGNs are affected by contamination from their host galaxies, we set a magnitude threshold when predicting the number of quasars. We find that variations in the u-band strategy can impact the number of quasar detections. Specifically, the difference between the baseline strategy and that with the largest total exposure in u is 15%. In contrast, changes in rolling strategies, DDF strategies, weather conditions, and Target of Opportunity observations result in variations below 2%. These results provide valuable insights for optimizing approaches to maximize the scientific output of quasar studies.

astro-ph.GA↗

arXiv2025

Do Low-Mass, Low-Luminosity AGNs Deviate from the Quasar Main Sequence?

We present a comprehensive spectroscopic and variability-based characterisation of a sample of low-luminosity active galactic nuclei (AGNs) hosting low mass black holes, identified by $Hβ$ full width at half maximum (FWHM) $< 2200$ km s$^{-1}$. While the narrow line widths are consistent with the formal definition of narrow-line Seyfert 1 (NLSy1) galaxies, the broader accretion and emission properties reveal key distinctions. The sample exhibits sub-Eddington accretion rates (median $\log R_{Edd} \approx -0.68$) and comparatively weak FeII emission (median $R_{FeII} \approx 0.61$), in contrast to the strong FeII strengths and high Eddington ratios characteristic of classical NLSy1s. Optical variability amplitudes, derived from Zwicky Transient Facility (ZTF) light curves, are similar to those typically seen in Seyfert 1 galaxies, with a median $\log(σ) \approx -0.68$, suggesting the AGN component's significant contribution to variability. In the optical plane of the 4D Eigenvector 1 (4DE1) parameter space, these sources occupy a distinct locus in the low-$R_{FeII}$, low-$R_{Edd}$ regime, suggesting a physically distinct accretion state. Our findings indicate that this population may represent a low-accretion analogue within the broader narrow-line AGN family, offering new insights into black hole growth at low mass scales.

astro-ph.GA↗

arXiv2025

Scalable and Robust Multiband Modeling of AGN Light Curves in Rubin-LSST

The Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) will monitor tens of millions of active galactic nuclei (AGNs) for a period of 10 years with an average cadence of 3 days in six broad photometric bands. This unprecedented dataset will enable robust characterizations of AGN UV/optical variability across a wide range of AGN physical properties. However, existing tools for modeling AGN light curves are not yet capable of fully leveraging the volume, cadence, and multiband nature of LSST data. We present EzTaoX, a scalable light curve modeling tool designed to take advantage of LSST's multiband observations to simultaneously characterize AGN UV/optical stochastic variability and measure interband time delays. EzTaoX achieves a speed increase of $\sim 10^2-10^4 \times$ on CPUs over current tools with similar capabilities, while maintaining equal or better accuracy in recovering simulated variability properties. This performance gain enables continuum time-delay measurements for all AGNs discovered by LSST -- both in the Wide Fast Deep survey and the Deep Drilling Fields -- thereby opening new opportunities to probe AGN accretion-flow geometries. In addition, EzTaoX's multiband capability allows robust characterization of AGN stochastic variability down to hourly timescales, facilitating the identification of accreting low-mass AGNs -- such as those residing in dwarf galaxies -- through their distinctive variability signatures.

astro-ph.GA↗

arXiv2025

Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. IV. Broad Emission Line Evolution Sequence Among Hα, Mg II, and Hβ

From a parent catalog of 561 changing-look active galactic nuclei (CL-AGNs) identified by Guo et al. (2025), we investigate the evolutionary sequence of broad emission lines using a redshift-selected subset (0.35 < z < 0.45) of 54 CL-AGNs whose Dark Energy Spectroscopic Instrument (DESI) spectra simultaneously cover the Hα, H\b{eta}, and Mg II emission lines. To provide a baseline for comparison, we construct a control sample of 19,897 normal Type 1 AGNs within the same redshift range from the DESI Year 1 data. Through stacked spectral analysis and line-continuum luminosity correlations, we identify a clear evolutionary sequence in all AGN where broad H\b{eta} fades first, followed by Mg II, and then Hα, as the AGN luminosity declines - consistent with expectations from reverberation mapping. This trend reflects a radially stratified broad line region (BLR), where each line's responsivity depends on its ionization potential and radial distance from the central engine. In addition, we find that more massive supermassive black holes (SMBHs) require lower Eddington ratios to fully suppress broad emission lines, suggesting that the critical accretion threshold for the CL phenomenon is mass-dependent. Our results present the first statistical confirmation of a stratified broad line fading sequence in AGNs, reinforcing the central role of accretion state in shaping BLR structure and visibility.

astro-ph.GA↗

arXiv2025

Feeding frenzy in the mighty black holes: what we could learn from them?

Eddington ratio is a paramount parameter governing the accretion history and life cycles of Active Galactic Nuclei (AGNs). This short review presents a multi-faceted view of the importance of the Eddington ratio spanning varied AGN studies. We find that the Eddington ratio is crucial for standardizing the Radius-Luminosity (R-L) relation - a necessary step for employing quasars (QSOs) as standardizable cosmological probes to help clarify the standing of the Hubble tension. In this data-driven era, we consolidated disparate aspects by developing novel relations borne out of large datasets, such as the robust, nearly universal anti-correlation between fractional variability and Eddington ratio derived from Zwicky Transient Facility (ZTF) data, which is vital for interpreting forthcoming high-cadence surveys like Rubin Observatory's LSST. Addressing the conundrum where JWST results suggest an overabundance of massive high-redshift black holes, we demonstrate that local AGNs offer clarification: Changing-Look AGNs (CLAGNs), driven by rapid Eddington ratio shifts, cluster in the low-accretion regime, a rate independently confirmed by our integral field spectroscopy and photoionization modeling of a well-known Seyfert 2 galaxy, rich in high-ionization, forbidden, coronal lines. Conversely, for the high-redshift, high-luminosity population where traditional reverberation mapping (RM) is highly impractical, photometric reverberation mapping (PRM) offers a rapid alternative to constrain accretion disk sizes, enabling efficient estimates of black hole masses and Eddington ratios. Finally, we developed tailored semi-empirical spectral energy distributions (SEDs) for extremely high-accretion quasars, successfully validating their characteristic extreme physical conditions.

astro-ph.GA↗

arXiv2025

The spectral energy distribution of extreme population A quasars

Knowledge of the broad-band active galactic nuclei (AGN) spectral energy distribution (SED) that ionizes the gas-rich broad emission line region is key to understanding the various radiative processes at play and their importance that eventually leads to the emission line formation. We modeled a spectral energy distribution for highly accreting quasars, also known as extreme population A sources, based mainly on observational data available in astronomical databases, and on accretion disk models for the unobservable far-UV domain. Our selection criterion is the RFeII parameter - the ratio of the optical FeII emission between 4434 A and 4684 A to the H-beta 4861 A intensity, RFeII > 1. This criterion is satisfied by highly-accreting, possibly super-Eddington, black holes. We analyzed 155 sources up to a redshift of approximately 1, previously reported in the literature, to construct a median radio-quiet SED spanning from radio to X-ray wavelengths. We find that the SED of quasars exhibits distinct features compared to lower accreting AGN, including a pronounced big blue bump and strong optical/UV emission along with a steep X-ray continuum. We classify the sources into radio-quiet, radio-intermediate, and radio-loud categories, observing that radio-intermediate and a subsample of radio-quiet AGN show a significant far-IR excess over the radio-quiet SED and the far-IR excess appears to be related to the prominence of Feii emission. There is an overall consistency between the new SED and the one obtained for high Eddington ratio quasars in previous work. We provide the SEDs in digital format for eventual applications.

astro-ph.GA↗

arXiv2025

Spatially-resolved spectro-photometric SED Modeling of NGC 253's Central Molecular Zone I. Studying the star formation in extragalactic giant molecular clouds

Studying the interstellar medium in nearby starbursts is essential for understanding the physical mechanisms driving these objects, thought to resemble young star-forming galaxies. This study aims to analyze the physical properties of the first spatially-resolved multi-wavelength SED of an extragalactic source, spanning six decades in frequency (from near-UV to cm wavelengths) at an angular resolution of 3$^{\prime\prime}$ (51 pc at the distance of NGC,253). We focus on the central molecular zone (CMZ) of NGC,253, which contains giant molecular clouds (GMCs) responsible for half of the galaxy's star formation. We use archival data, spanning optical to centimeter wavelengths, to compute SEDs with the GalaPy and CIGALE codes for validation, and analyze stellar optical spectra with the \textsc{starlight} code. Our results show significant differences between central and external GMCs in terms of stellar and dust masses, star formation rates (SFRs), and bolometric luminosities. We identify the best SFR tracers as radio continuum bands at 33 GHz, radio recombination lines, and the total infrared luminosity (L$_{\rm IR}$; 8-1000$μ$m), as well as 60$μ$m IR emission. BPT and WHAN diagrams indicate shock signatures in NGC~253's nuclear region, associating it with AGN/star-forming hybrids, though the AGN fraction is negligible ($\leq$7.5%). Our findings show significant heterogeneity in the CMZ, with central GMCs exhibiting higher densities, SFRs, and dust masses compared to external GMCs. We confirm that certain centimeter photometric bands can reliably estimate global SFR at GMC scales.

astro-ph.GA↗

arXiv2025

Exploring Quasar Variability With ZTF at 0<z<3: A Universal Relation with Eddington Ratio

Quasars, powered by accretion onto supermassive black holes (SMBHs), exhibit significant variability, offering insights into the physics of accretion and the properties of the central engines. In this study, we analyze photometric variability and its correlation with key quasar properties, including black hole mass ($M_{\mathrm{BH}}$) and nuclear luminosities, using 915 quasars with $0\leq z<3.0$ from the AQMES sample monitored within SDSS-V. Variability metrics were derived from approximately 6-year light curves provided by the Zwicky Transient Facility -- ZTF, while SMBH masses and luminosities were obtained from the SDSS DR16 quasar catalog of \citet{wu2022catalog}. We identify a strong anti-correlation between variability amplitude and luminosity, which strengthens with redshift, and a redshift-dependent trend for $M_{\mathrm{BH}}$: a positive correlation at low redshifts, no significant correlation at intermediate redshifts, and an anti-correlation the highest redshifts. Our main finding is a robust anti-correlation between photometric variability amplitude and Eddington ratio, consistent across redshift bins. We present a general equation encapsulating this relationship, that appears to be almost free of redshift dependence, enabling predictions of quasar variability based on accretion parameters {\bf or vice-versa}. The derived relation with the Eddington ratio provides a unified framework for interpreting variability in active galactic nuclei (AGN) and facilitates future studies of quasar variability using high-cadence surveys, such as the Vera C. Rubin Observatory's Legacy Survey of Space and Time -- LSST.

astro-ph.GA↗

arXiv2025

The Spectroscopic Stage-5 Experiment

The existence, properties, and dynamics of the dark sectors of our universe pose fundamental challenges to our current model of physics, and large-scale astronomical surveys may be our only hope to unravel these long-standing mysteries. In this white paper, we describe the science motivation, instrumentation, and survey plan for the next-generation spectroscopic observatory, the Stage-5 Spectroscopic Experiment (Spec-S5). Spec-S5 is a new all-sky spectroscopic instrument optimized to efficiently carry out cosmological surveys of unprecedented scale and precision. The baseline plan for Spec-S5 involves upgrading two existing 4-m telescopes to new 6-m wide-field facilities, each with a highly multiplexed spectroscopic instrument capable of simultaneously measuring the spectra of 13,000 astronomical targets. Spec-S5, which builds and improves on the hardware used for previous cosmology experiments, represents a cost-effective and rapid approach to realizing a more than 10$\times$ gain in spectroscopic capability compared to the current state-of-the-art represented by the Dark Energy Spectroscopic Instrument project (DESI). Spec-S5 will provide a critical scientific capability in the post-Rubin and post-DESI era for advancing cosmology, fundamental physics, and astrophysics in the 2030s.

astro-ph.CO↗

arXiv2025

Identifying Doppelganger Active Galactic Nuclei across redshifts from spectroscopic surveys

Active Galactic Nuclei (AGNs) are among the most luminous objects in the universe, making them valuable probes for studying galaxy evolution. However, understanding how AGN properties evolve over cosmic time remains a fundamental challenge. This study investigates whether AGNs at low redshift (nearby) can serve as proxies for their high-redshift (distant) counterparts by identifying spectral 'doppelgängers', AGNs with remarkably similar emission line properties despite being separated by vast cosmic distances. We analyze key spectral features of bona fide AGNs using the Sloan Digital Sky Survey's Data Release 16, including continuum and emission lines: Nitrogen (N V), Carbon (C IV), Magnesium (Mg II), Hydrogen-beta (H$β$), and Iron (Fe II - optical and UV) emission lines. We incorporated properties such as equivalent width, velocity dispersion in the form of full width at half maximum (FWHM), and continuum luminosities (135nm, 300nm, and 510nm) closest to these prominent lines. Our initial findings suggest the existence of multiple AGNs with highly similar spectra, hinting at the possibility that local AGNs may indeed share intrinsic properties with high-redshift ones. We showcase here one of the better candidate pairs of AGNs resulting from our analyses.

astro-ph.GA↗

arXiv2025

The discovery and characterization of Earth-crossing asteroid 2024 YR$_4$

We describe observations and physical characteristics of Earth-crossing asteroid 2024 YR$_4$, discovered on 2024 December 27 by the Asteroid Terrestrial-impact Last Alert System. The asteroid has semi-major axis, $a$ = 2.52 au, eccentricity, $e$ = 0.66, inclination $i$ = 3.41$^{\circ}$, and a $\sim$0.003 au Earth minimum orbit intersection distance. We obtained g, r, i, and Z imaging with the Gemini South/Gemini Multi-Object Spectrograph on 2025 February 7 and Y and J imaging with the Keck/Multi-Object Spectrometer For Infra-Red Exploration on 2025 February 12. We measured a g-i spectral slope of 13$\pm$3 $\%$/100 nm, and color indices g-r = 0.70 $\pm$ 0.10, r-i = 0.25$\pm$0.06, i-Z = -0.27 $\pm$ 0.10, and Y-J = 0.41 $\pm$ 0.10. 2024 YR$_4$ has a spectrum that best matches R-type and Sa-type asteroids and a diameter of $\sim$30-65 m using our measured absolute magnitude of 23.9 $\pm$ 0.3 mag, and assuming an albedo of 0.15-0.4. The lightcurve of 2024 YR$_4$ shows $\sim$0.4 mag variations with a rotation period of $\sim$1170 s. We use photometry of 2024 YR$_4$ from Gemini and other sources taken between 2024 December to 2025 February to determine the asteroid's spin vector and shape, finding that it has an oblate, $\sim$3:1 a:c axial ratio and a pole direction of $λ$, $β$ = $\sim$42$^{\circ}$, $\sim$-25$^{\circ}$. Finally, we compare the orbital elements of 2024 YR$_4$ with the NEO population model and find that its most likely sources are resonances between the inner and central Main Belt.

astro-ph.EP↗

arXiv2025

The S-PLUS Fornax Project (S+FP): Mapping globular clusters systems within 5 virial radii around NGC 1399

We present the largest sample ($\sim$13,000 candidates, $\sim$3000 of wich are bona-fide candidates) of globular cluster (GCs) candidates reported in the Fornax Cluster so far. The survey is centered on the NGC 1399 galaxy, extending out to 5 virial radii (\rv) of the cluster. We carried out a photometric study using images observed in the 12-bands system of the Southern Photometric Local Universe Survey (S-PLUS), corresponding to 106 pointings, covering a sky area of $\sim$208 square degrees. Studying the properties of spectroscopically confirmed GCs, we have designed a method to select GC candidates using structural and photometric parameters. We found evidence of color bimodality in 2 broad bands colors, namely $(g-i)_{0}$ and $(g-z)_{0}$, while, in the narrow bands, we did not find strong statistical evidence to confirm bimodality in any color. We analyzed the GCs luminosity functions (GCLF) in the 12-bands of S-PLUS, and we can highlight two points: a) due to the relatively shallow depth of S-PLUS, it is only possible to observe the bright end of the GCLF and, b) at that level, in all the bands it can be appreciated the log-normal distribution typical for GC systems. With the spatial coverage reached in this study, we are able for the first time explore the large scale distribution of GCs within and around a galaxy cluster. In particular, we noted that the GCs might be clustered along substructures, which traces the current cluster build up.

astro-ph.GA↗

arXiv2025

Galaxy evolution in compact groups II. Witnessing the influence of major structures in their evolution

Compact groups (CGs) of galaxies are extreme environments for morphological transformations and the cessation of star formation. Though initially considered isolated, it is now recognised that many CGs are embedded in larger structures. We aim to understand the dynamics of CGs and how their surrounding environments impact their physical properties. We selected 316 CGs in the Stripe 82 region (1011 galaxies) and 2281 field galaxies as a control sample. At least 41% of CGs are part of major structures (non-isolated CGs). We find a bimodal distribution in the effective radius ($R_e$)-Sersic index ($n$) plane for transition galaxies ($(u-r) > 2.3$ and $n<2.5$) in CGs. Transition galaxies in isolated CGs are denser in the $R_e-n$ plane for $n < 1.75$, while those in non-isolated CGs show a smoother increase in $n$, with 62% having $n > 1.5$. This suggests that many have undergone morphological transformation, contributing to the compact galaxy population. Galaxies in CGs have lower mean specific star formation rates (sSFR) than the control sample, with non-isolated CGs showing even lower sSFR, indicating stronger star formation suppression. Non-isolated CGs also have a higher fraction of quenched galaxies. When dividing by morphology, significant differences arise only for early-type galaxies (ETGs; $(u-r) > 2.3$ and $n>2.5$). In isolated CGs, ETGs show lower quenched fractions and higher sSFR in low-mass bins ($\log(M_/M_{\odot}) < 11$), suggesting sustained star formation. In non-isolated CGs, ETGs show higher quenched fractions and lower sSFR in high-mass bins ($\log(M_/M_{\odot}) > 11$), underscoring the environmental suppression of star formation. We propose that major structures accelerate morphological transformations and facilitate preprocessing. Our results highlight the need to consider larger structures when analysing CGs, as they significantly affect galaxy evolution.

astro-ph.GA↗