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L. Wang

Publications and source records attributed to L. Wang.

At least 19 recordsLinked to original sources
arXiv2026

EBS and in-beam $\gamma$-ray investigation of FCVA-prepared Cr$_2$O$_3$ targets for low-energy $^{16}$O+$^{16}$O fusion experiments

The Cr$_2$O$_3$ solid target for low-energy $^{16}$O+$^{16}$O fusion experiments was fabricated using filtered cathodic vacuum arc (FCVA) deposition. Its composition, oxygen areal density and impurity content were characterized by elastic backscattering spectrometry (EBS), and the impurity-induced background contributions were investigated by in-beam $\gamma$-ray spectroscopy. EBS results indicate that the Cr$_2$O$_3$ film exhibits good stoichiometry and uniformity, with $^{16}$O areal densities ranging from $(3.24-3.25)\times10^{17}$ atoms/cm$^2$. The EBS analysis reveals a carbon atomic fraction of approximately 1.25-1.29\% in the Cr$_2$O$_3$ layer, while a large amount of carbon impurities are also identified on the surface of Cr substrate. In-beam $\gamma$-ray spectra reveal prominent transitions associated with $^{27}$Al and $^{24}$Mg at 844, 1015, and 1369 keV, mainly originating from $^{12}$C+$^{16}$O fusion reactions induced by carbon impurities under $^{16}$O irradiation. Meanwhile, characteristic $\gamma$-rays emissions from evaporation channels of the $^{16}$O+$^{16}$O reaction, including $^{31}$S, $^{31}$P, and $^{28}$Si, were also observed and can be used to extract the $^{16}$O+$^{16}$O fusion cross sections. This work provides an experimental basis for the development of high-purity oxide targets and the optimization of target configurations for future low-background $^{16}$O+$^{16}$O fusion cross section measurements.

physics.ins-det↗
arXiv2026

Out-of-equilibrium spin-valley dynamics of ferromagnets in topological Chern bands

Understanding quantum matter far from equilibrium is a central goal of modern physics. Twisted MoTe2 bilayers constitute a promising platform for exploring this frontier by combining strong Coulomb interactions, nontrivial band geometry, and optical control. Here, we exploit this setting to investigate the role of topology and many-body correlations in the out-of-equilibrium dynamics of ferromagnets in Chern bands. Using a focused circularly polarized light pulse, we create a local magnetic domain oriented opposite to an external magnetic field and directly image its subsequent spin-valley relaxation in spatially and time-resolved low-temperature experiments. We demonstrate that in the vicinity of both integer and fractional Chern insulating states, the dynamics is governed by qualitatively different mechanisms than in ferromagnetic metals. Whereas metallic domains collapse by shrinking, Chern domains melt via thermal activation, resulting in drastically different temporal spin evolution and orders-of-magnitude longer relaxation times. These findings demonstrate the influence of topology and strong correlations on far-from-equilibrium collective spin phases, opening new opportunities for dynamical control of ferromagnets in the quantum Hall regime.

cond-mat.mes-hall↗
arXiv2026

Nanosecond timescale plasticity in shock-compressed polycrystalline MgO: evidence for transition in mechanism above 100 GPa

The mechanical properties of ceramics under extreme conditions directly impact applications ranging from shielding spacecrafts, designing plasma facing materials in nuclear fusion to understanding the rheology of deep planetary interiors. Here, we use polycrystalline MgO as a model ceramic to understand the high-pressure-temperature mechanical behaviour of such materials under extreme strain rates. We use laser-driven shock compression up to 175(15) GPa on the principal Hugoniot along with ultrafast diagnostics at the European X-ray Free Electron Laser to probe the dominant deformation mechanisms with changing P -T conditions. These near-instantaneous time-resolved snapshots, coupled with elasto-viscoplastic self-consistent (EVPSC) simulations, strongly suggest that MgO attains plastic regime in the nanoseconds scale accompanied by a pressure-mediated change in dominant slip system between 95 and 175 GPa. This work provides a new direct window into the deformation dynamics of polycrystalline ceramics under high-velocity impacts.

cond-mat.mtrl-sci↗
arXiv2026

Euclid Quick Data Release (Q1). Searching for radio-selected \Euclid-dark galaxies in the EDF-N

We present and investigate the properties of a sample of radio-selected, Euclid-dark galaxies, identified from LOFAR HBA observations at 144 MHz within the Euclid Deep Field-North (EDF-N). Starting from radio sources lacking optical counterparts in previous surveys, but detected with Spitzer/IRAC, we identified 166 galaxies with no emission at a more than $3\sigma$ level in Euclid Quick Release 1 (Q1) images, and no matches in the Euclid Q1 catalogue. To minimise contamination from nearby sources, we selected a sub-sample of 88 isolated galaxies. By exploiting multi-band images and catalogues available for the EDF-N, we inferred the physical properties of our sample via SED fitting. The resulting redshift distribution spans $0.4 \leq z_\mathrm{ph} \leq 5.0$. We used recent sub-arcsecond imaging from the International LOFAR Telescope to constrain the nature of the compact radio emission through brightness temperature estimates. By combining this information with the radio excess relative to the infrared/radio correlation (IRRC), we searched for possible active galactic nuclei (AGN) activity. Approximately 40% of our sources show evidence of AGN activity. The Euclid-dark sources detected in the far-infrared are consistent with a population of heavily obscured, massive star-forming galaxies with high star formation rates. Their location above the star-forming main sequence is consistent with similar near-infrared-dark galaxy populations reported in the literature. We also performed a UV-to-radio median stacking analysis, finding that the two subsamples exhibit similar global physical properties and differ primarily in their radio emission. These preliminary results indicate that the wide area covered by Euclid enables the identification of a higher fraction of systems in which intense star formation and AGN activity coexist, likely capturing a key phase of galaxy--black hole co-evolution.

astro-ph.GA↗
arXiv2026

JWST Medium-Resolution Infrared Spectroscopy of SN 2022acko: Tracing Molecule Formation in the Nebular Phase

The Type II supernova (SN II) SN 2022acko was the first to be spectroscopically observed by the James Webb Space Telescope ($\textit{JWST}$). Here, we analyze SN 2022acko's second and third $\textit{JWST}$ spectra obtained at $+259$ and $+368$ d. We identify strong features associated with hydrogen along with Intermediate-Mass and Iron-Group Elements (IM/IGEs). The medium-resolution mode of $\textit{JWST}$/MIRI uniquely enables the isolation of emission features, allowing us to determine the structure of SN 2022acko, directly coupling the spectroscopic features and the explosion mechanism. We find that IMEs display peak velocities of $~ 300$ km s$^{-1}$, significantly larger than the $~ 100$ km s$^{-1}$ measured for H, He, and IGEs. We suggest a bipolar outflow best explains this ejecta distribution, although Rayleigh-Taylor instabilities may also contribute. Additionally, we find a bulk velocity offset of $~ 97.4^{+86.3}_{-42.3}$ km s$^{-1}$ in the ejecta which we associate with the natal kick of a neutron star. CO emission is also detected while no SiO or dust signatures are observed. We fit the CO first-overtone and fundamental bands with MOFAT and find a clumped distribution is required with a CO mass increasing from $1.55\times10^{-4}$ M$_{\odot}$ at $+259$ to $2.47\times10^{-4}$ M$_{\odot}$ at $+368$ d. This CO mass is approximately an order of magnitude lower than that of SN 2024ggi. As the first $\textit{JWST}$ nebular-phase study of a low-mass SN II, this work shows that such events form substantially less molecules than more massive SNe II, with dust formation likely occurring on longer timescales, if at all.

astro-ph.HE↗
arXiv2026

Euclid Quick Data Release (Q1): The impact of AGN emission on SED-derived physical properties

The Euclid Quick Data Release (Q1) is a powerful dataset to study active galactic nuclei (AGN) and their host galaxies. Deriving their physical properties through multi-component spectral energy distribution (SED) fitting is a challenging task for AGN, but it is greatly aided by the Euclid near-infrared photometry. Here we present a new method to quantify the reliability of SED-derived parameters, such as AGN bolometric and monochromatic luminosities, host's stellar mass $M_\star$, star-formation rate (SFR) and specific star-formation rate (sSFR), by using mock SEDs of AGN built by combining observed SEDs of QSOs and galaxies. We apply this methodology to the ${\sim}1$ million Q1 AGN candidates, constructing a catalogue of AGN and host galaxy properties, alongside their respective reliability values. With a reliability threshold at 0.5, we find 88\% of sources with robust stellar masses and 76\% with reliable AGN luminosities. Moreover, through SED fitting we also measure the AGN fraction $f_{\rm AGN}$ of the total mid-infrared flux and we use its lower-limit to select AGN. A $f_{\rm AGN, \, low} > 0.075$ threshold yields 85\% completeness and purity. Comparable to colour-colour AGN selections, this method has the advantage of being less affected by redshift evolution and exploring fainter magnitudes. Additionally, by comparing the AGN and host galaxy parameters across different identification methods, we find that the probed range in stellar mass and AGN luminosity can be quite different. This highlights the importance of combining different approaches and accounting for their selection biases when studying AGN and their role in galaxy evolution. Finally, for the X-ray detected sample, we present the X-ray to mid-IR luminosity relation, and the correlation between stellar mass and bolometric luminosity as a function of redshift, in good agreement with previous results.

astro-ph.GA↗
arXiv2026

Nematicity in LaFeAsO single crystals studied by elastoresistance, high-resolution thermal expansion and shear-modulus measurements

Nematicity in LaFeAsO single crystals is studied by means of high-resolution thermal expansion, shear modulus, and elastoresistivity measurements. A softening of the shear modulus $C_{\rm 66}$ towards the structural phase transition at $T_{\rm S}$ is observed. In addition, a similar Curie-Weiss-like divergence of the nematic susceptibilities is found in the temperature dependence of both $\chi^{sh}$ and $\chi^{er}$, which are deduced from the shear modulus (sh) and the elastoresistivity (er) studies, respectively. These observations provide evidence for an electronic origin of nematicity in LaFeAsO. The characteristic energy of the coupling between the lattice and the electronic degrees of freedom is deduced to $\sim$30~K. The comparison to corresponding measurements on BaFe$_2$As$_2$ single crystals reveals a very similar temperature dependence of the shear modulus but yields contrasting results for $\chi^{er}$ : In BaFe$_2$As$_2$, $\chi^{er}$ diverges similarly as the uncoupled nematicity deduced from the shear modulus data as it is expected from the underlying Landau theory. In contrast, the Weiss temperatures of $\chi^{er}$ and $\chi^{sh}$ are significantly different in LaFeAsO. This difference is at odds with the commonly anticipated theories of resistivity anisotropy and electronic nematicity in iron pnictides.

cond-mat.supr-con↗
arXiv2026

Emergent superconductivity at 16.3 K in an altermagnetic candidate Na$_{2-x}$V$_2$Se$_2$O with broken inversion symmetry

Altermagnets (AMs), characterized by zero net magnetization and momentum-dependent spin splitting, are anticipated to hold significant potential for generating multiple exotic and uncommon superconducting states. However, superconductivity has not yet been realized in AMs to date. Recently, two-dimensional (2D) V$_2$Ch$_2$O (Ch = Se, Te) monolayers, as well as AV$_2$Ch$_2$O (A = K, Rb, Cs) crystals containing [V$_2$Ch$_2$O]$^{\delta -}$ building layers, have been predicted and/or demonstrated to be promising altermagnetic materials. Our preliminary attempts to explore superconductivity in these materials by applying pressure or chemical doping were unsuccessful. Here we report the discovery of superconductivity at a relatively high transition temperature of ~ 16.3 K in a newly synthesized layered compound, Na$_{2-x}$V$_2$Se$_2$O, a variant of AV$_2$Ch$_2$O. In this structure, the [V$_2$Ch$_2$O]$^{\delta -}$ layers are interspersed with double layers of Na$^+$ instead of a single layer of A$^+$, with sodium sites being only half-filled. This new family of layered vanadium oxychalcogenides, lacking inversion symmetry, represents an intriguing platform for exploring altermagnetic superconductors, and holds the potential to reveal novel phenomena, such as topological states, van Hove singularities, and finite-momentum superconductivity. Furthermore, this material acts as a "bridge" between the cuprate/nickelate and iron-pnictide high temperature superconductors, providing new hope and opportunity to expand the category of layered superconductors with higher critical temperatures (T$_c$) and enhancing our understanding of the underlying mechanisms in these systems.

cond-mat.supr-con↗
arXiv2026

Learning Unified Control of Intrinsic Nonlinear Spin Dynamics in Atomic Qudits for Magnetometry

Generating and preserving metrologically useful quantum states is a central challenge in quantum-enhanced metrology. In low-field atomic magnetometry with multilevel atoms, the nonlinear Zeeman (NLZ) effect is both a resource and a limitation. It can generate internal spin squeezing within a single atomic qudit, but under fixed readout it also rotates and distorts the measurement-relevant quadrature, limiting the usable metrological gain. The problem is further complicated by the time dependence of both the squeezing axis and the nonlinear evolution itself. Here we show that reinforcement learning can transform NLZ dynamics from a source of readout degradation into a sustained metrological resource. Using only experimentally accessible low-order spin moments, a trained agent identifies a unified control policy for this class of intrinsically nonlinear sensing dynamics. We illustrate the approach in the $f=21/2$ manifold of $^{161}\mathrm{Dy}$, where the learned policy rapidly prepares strongly squeezed internal states and stabilizes more than $4\,\mathrm{dB}$ of fixed-axis spin squeezing under continuous NLZ evolution. Including state-preparation overhead, the learned protocol yields a single-atom magnetic-field sensitivity of $13.9\,\mathrm{pT}/\sqrt{\mathrm{Hz}}$, approximately $3\,\mathrm{dB}$ beyond the standard quantum limit. Our results establish learning-based control as an experimentally feasible route for converting unavoidable intrinsic nonlinear dynamics in multilevel atomic sensors into operational metrological advantage.

quant-ph↗
arXiv2026

MiroThinker-1.7 & H1: Towards Heavy-Duty Research Agents via Verification

We present MiroThinker-1.7, a new research agent designed for complex long-horizon reasoning tasks. Building on this foundation, we further introduce MiroThinker-H1, which extends the agent with heavy-duty reasoning capabilities for more reliable multi-step problem solving. In particular, MiroThinker-1.7 improves the reliability of each interaction step through an agentic mid-training stage that emphasizes structured planning, contextual reasoning, and tool interaction. This enables more effective multi-step interaction and sustained reasoning across complex tasks. MiroThinker-H1 further incorporates verification directly into the reasoning process at both local and global levels. Intermediate reasoning decisions can be evaluated and refined during inference, while the overall reasoning trajectory is audited to ensure that final answers are supported by coherent chains of evidence. Across benchmarks covering open-web research, scientific reasoning, and financial analysis, MiroThinker-H1 achieves state-of-the-art performance on deep research tasks while maintaining strong results on specialized domains. We also release MiroThinker-1.7 and MiroThinker-1.7-mini as open-source models, providing competitive research-agent capabilities with significantly improved efficiency.

cs.CL↗
arXiv2026

Euclid preparation. Far-infrared predictions for Euclid galaxy catalogues: cluster, protocluster, and field

The MAMBO mock galaxy catalogue, based on the Millennium Simulation with empirically assigned galaxy properties, provides predictions of FIR fluxes and physical parameters of Euclid-detectable galaxies. Predicted FIR flux distributions confirm that only the brightest Euclid sources will be detectable in existing FIR surveys. We employ stacking to measure the mean dust properties as a function of stellar mass and redshift. We find dust temperatures and infrared luminosities increase with redshift across all mass bins, while dust masses remain roughly constant. FIR number counts from MAMBO show overall good agreement with observations, and the total infrared luminosity function reproduces published estimates across most redshift ranges, extending to z~10. Comparing the Euclid Wide and Deep Surveys, we find that the EDS recovers the total IRLF to fainter luminosities and higher redshifts (up to z~6 in $I_E$), although its detectability falls below 80% at z>4, whereas the EWS becomes strongly incomplete beyond z~2. We also examine the dependence of the IRLF on environment. Schechter fits indicate that the faint-end slope $\alpha$ flattens with redshift for cluster and protocluster galaxies, while remaining approximately constant for field populations. Imposing additional detection limits from Herschel-PACS and SPIRE shows that only the most luminous ($L_{IR}$ > $10^{12.5}$ $L_{\odot}$) galaxies remain detectable at z~4, but the limited MAMBO area (3.14$deg^2$) is inadequate for statistically robust (>3$\sigma$) constraints. Survey areas at least 30 times larger are required. Overall, the MAMBO FIR extension reproduces key number count and IRLF trends, provides realistic predictions for FIR-detected Euclid galaxies, and highlights the importance of synergies with current and future FIR/sub-mm facilities to probe environmental dependence with sufficient depth and area.

astro-ph.GA↗
arXiv2026

The major merger-active galactic nucleus connection up to the cosmic noon

Galaxy major mergers are a potential mechanism for triggering active galactic nuclei (AGN) activity, but their role remains debated, particularly beyond the local Universe. We aim to shed light on the merger-AGN connection at $z=0.5$-$2$, exploiting the multi-wavelength datasets and {\it James Webb Space Telescope} (JWST) observations in the COSMOS field. We construct a stellar mass-limited sample and identify AGN via mid-infrared (MIR) colours, X-ray detections, and spectral energy distribution (SED) fitting. We train convolutional neural networks to identify mergers with mock JWST observations. We create non-AGN and non-merger control samples matching the redshift, stellar mass, and star-formation rate distributions of the AGN and mergers. We find AGN to be moderately more frequent in mergers than in non-mergers, with excess ratios ranging from $\sim2.5$ (X-ray AGN) to $\sim1.3$ (MIR) and $\sim 1.1$-1.2 (SED AGN). Similarly, AGN galaxies show a higher merger fraction ($f_{merg}$) than non-AGN controls. We then study $f_{merg}$ as a function of relative and absolute AGN power, utilising the AGN fraction ($f_{AGN}$) and accretion disc luminosity (L$_{disc}$) parameters. We uncover a $f_{merg}$-$f_{AGN}$ relation with two regimes: $f_{merg}$ stays roughly flat for less-dominant AGN ($f_{AGN}<0.8$) but increases at $f_{AGN}>0.8$ for the MIR and X-ray AGN, and more gently for SED AGN, where mergers appear to be the main triggering mechanism. Additionally, $f_{merg}$ increases monotonically as a function of L$_{disc}$, for all AGN types, reaching $f_{merg}>50\%$ for the most luminous AGN (L$_{disc} \gtrsim 10^{46}\,{erg\,s^{-1}}$). Overall, our results suggest that major mergers can trigger AGN out to the cosmic noon at $z\sim2$. Furthermore, the role of major mergers shows a clear dependence on AGN luminosity and remains the principal mechanism for fuelling the most powerful AGN.

astro-ph.GA↗
arXiv2026

Calibrating Mid-Infrared Emission Features As Diagnostics of Star Formation in Infrared-Luminous Galaxies via Radiative Transfer Modeling

Luminous infrared galaxies are key sites of obscured stellar mass assembly at z > 0.5. Their star formation rates (SFRs) are often estimated using the luminosities of the 6.2 micron and 11.2 micron polycyclic aromatic hydrocarbon (PAH) features, or those of the [Ne II] and [Ne III] fine-structure lines, as they are minimally affected by obscuration. It is uncertain whether the calibration of these features as SFR tracers depends on the starburst bolometric luminosity or the level of Active Galactic Nucleus (AGN) activity. We here investigate the relationship between the luminosities of PAH and Neon lines with star formation rate for highly luminous objects using radiative transfer modeling and archival observations of 42 local Ultraluminous (>= 10^12 L_sun) Infrared Galaxies (ULIRGs). We find that PAH and [Ne II] features arise mainly in star-forming regions, with small contributions from the AGN or host, but that the [Ne III] line has a mixed contribution from both star formation and AGN activity. We present relations between L_PAH and L_NeII, and both starburst luminosity and SFR. We find relations for lower luminosity (L_IR ~= 10^10-10^12 L_sun) systems underestimate the SFRs in local ULIRGs by up to ~1 dex. The 6.2 micron and 11.2 micron PAH features, and the [Ne II] line, are thus good tracers of SFR in ULIRGs. We do not find that a more luminous AGN affects the relationship between SFR and PAH or Neon luminosity, but that it can make PAH emission harder to discern. Our results and derived relations are relevant to studies of star-forming and composite galaxies at z < 3 with the James Webb Space Telescope.

astro-ph.GA↗
arXiv2026

Search for Cosmic Ray Electron Boosted Dark Matter with the CDEX-10 Experiment

We present new constraints on the cosmic ray electron boosted light dark matter (CReDM) using the 205.4 kg$\cdot$day data of the CDEX-10 experiment located at the China Jinping Underground Laboratory. The cosmic ray electron spectrum and distribution in the Galaxy are generated by the $\tt GALPROP$ code package. In the calculation process of DM-electron scattering process in the Galaxy, we consider the energy-dependency of the DM-electron scattering cross section. The constraints on CReDM are set for both heavy and light mediator scenarios using the CDEX-10 dataset. The result exceeds previous Standard Halo Model (SHM) limits for DM mass lower than 0.6 MeV in heavy mediator case and corresponds to the best sensitivity among all direct detection experiments from 1 keV to 0.5 MeV in the light mediator scenario.

hep-ex↗
arXiv2025

Spectroscopy of Wigner crystal polarons in an atomically thin semiconductor

Strongly interacting electrons in two-dimensional systems can spontaneously break translational symmetry, forming a periodic Wigner crystal. Although these crystals have been realized in several platforms, experimental studies of their collective many-body excitations in the absence of a magnetic field remain an outstanding challenge. Here, we access this regime optically by uncovering Wigner crystal polarons: novel light-matter excitations arising from the dressing of excitons by collective excitations of the Wigner crystal. These hybrid quasiparticles manifest as new optical resonances in cryogenic reflectance spectra of a charge-tunable WSe$_2$ monolayer, appearing concurrently with previously identified exciton umklapp transitions. In contrast to the latter, the energies of Wigner crystal polarons are governed not only by the electronic lattice constant but also by their hybridization with attractive exciton-polarons, whose strength is controlled by electronic interactions. These novel many-body excitations provide an optical interface to the spin state of the Wigner crystal, which as we demonstrate, can be controlled both magnetically and optically. Our work establishes layered materials as a unique platform for exploring dynamical impurity dressing by strongly correlated electronic orders.

cond-mat.mes-hall↗
arXiv2025

Pressure-Induced Changes in Structure, Magnetic Order and Development of Superconductivity in the Ferromagnetic Topological Insulator MnBi8Te13

We report a comprehensive study of pressure-induced evolution of the magnetism and development of superconductivity (SC) in MnBi8Te13, a promising ambient pressure, ferromagnetic (FM) topological insulator candidate. By employing high-pressure electrical transport, magnetoresistance, DC magnetic susceptibility, and X-ray diffraction measurements, we construct a detailed temperature-pressure phase diagram. At ambient pressure, MnBi8Te13 exhibits FM ordering with an easy-axis along the c-axis which is progressively suppressed under pressure and replaced by an antiferromagnetic (AFM) order. Density functional theory calculations predicted an evolution from FM to a G-type AFMg2 phase near 5 GPa. Above 16.6 GPa, a bulk SC state emerges with a maximum transition temperature ~6.8 K, as confirmed by resistance and magnetic susceptibility measurements. This pressure-induced SC may co-exist with another AFM dome that shows a weak anomaly in the transport data. In contrast, our work on MnBi6Te10 shows no SC up to 40 GPa. Indeed, in contrast to MnBi8Te13, the MnBi2Te4(Bi2Te3)n compounds with n < 3, didn't exhibit SC, highlighting the crucial role of Mn concentration in stabilizing SC. The observation of pressure-induced FM-AFM-SC transitions in MnBi8Te13 not only establishes it as a rare Mn-based SC but also provides a platform to study the interplay between magnetism, SC, and potentially nontrivial band topology in correlated magnetic materials.

cond-mat.supr-con↗
arXiv2025

AMKID -- a large KID-based camera at the APEX telescope

The thermal emission at sub-millimeter wavelengths carries unique information in many astronomical applications ranging from disks and planet formation around young stars, to galaxy evolution studies at cosmological distances. Advancing on the mapping speed to detect this faint emission in ground-based astronomy has been a technical challenge for decades. The APEX Microwave Kinetic Inductance Detector (AMKID) camera was designed to accomplish this task. The instrument is a wide field-of-view camera based on kinetic inductance detectors. It is installed on the 12~meter APEX telescope in Chile at 5.100~meters above see level. The instrument operates dual color, covering simultaneously the 350~GHz and 850~GHz atmospheric windows. It has a large field-of-view of 15.3'x15.3', and an unprecedented number of pixels: 13.952~detectors in the high frequency band and 3.520~detectors in the low frequency band. Here we present a complete description of the instrument design and construction together with results of the successful low frequency array (LFA) commissioning campaign executed during the last year. The LFA performance is in good agreement with design parameters, with detector sensitivity of 2.2~mK$\sqrt{s}$ and diffraction limited beam sizes of 17.0''. On-sky measurements demonstrate a sensitivity of 70-90~mJy$\sqrt{s}$ per detector when operating under good atmospheric conditions (PWV below 1.0mm). With this performance the LFA regularly achieve a mapping sensitivity of 25~mJy when mapping a square degree in an hour. AMKID on APEX with its dual color observing capabilities, high sensitivity, large field-of-view and high angular resolution holds the promise to open a new range of science with the APEX telescope.

astro-ph.IM↗
arXiv2025

XID+PRIMA, II: Stepping Through Hyperspectral Imaging to Deblend PRIMAger Beyond the Extragalactic Confusion Limit

The PRobe far-Infrared Mission for Astrophysics concept aims to map large areas with spectral coverage and sensitivities inaccessible to previous FIR space telescopes, covering 25-235um. We synthesise images representing a deep imaging survey, with realistic instrumental and confusion noise, reflecting the latest PRIMAger instrument specifications. We present a new Bayesian modelling approach XID+stepwise that exploits PRIMAger's hyperspectral imaging to derive self-consistent, informative flux priors by sequentially propagating constraints from short to long wavelengths. With Euclid-like prior source positions, this method recovers fluxes to within 20% to 0.2-0.7 mJy across 45-84 um, which correspond to factors of 1.3-3.4 fainter than the confusion limit. For the most confusion-dominated channels, accurate fluxes are measured to 0.9, 2.5, 7.6 and 14.8 mJy at 92, 126, 183 and 235 um, respectively, which are factors of 3-5 better than the confusion limit. Using a deeper Euclid-based prior catalogue and weak ancillary flux priors at 25 um yields further improvements, reaching up to a factor ~7 fainter than the confusion limit at 96 um. Additionally, we demonstrate that positional priors from blind source detection followed by deblending via XID+ enables PRIMAger to achieve sensitivity beyond the confusion limits using PRIMAger data alone. We show that IR-luminous galaxies at z~2 are robustly detected in a large fraction of the PRIMAger channels (>98% in 12 out of the 16 considered channels), providing dense sampling of the FIR SED even for sources several factors below the confusion limit. We explore the impact on our results for a range of systematic effects, including cirrus contamination, optical degradation, and calibration uncertainties. These findings indicate that confusion noise will not limit the key science from PRIMA extragalactic imaging surveys when employing XID+.

astro-ph.IM↗