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Fermion mass hierarchy in an extended left-right symmetric model
(Springer Science and Business Media Deutschland GmbH, 0023) Bonilla, Cesar; Cárcamo Hernández A.E; Kovalenko, Sergey; Lee H.; Pasechnik R; Schmidt, Ivan
We present a Left-Right symmetric model that provides an explanation for the mass hierarchy of the charged fermions within the framework of the Standard Model. This explanation is achieved through the utilization of both tree-level and radiative seesaw mechanisms. In this model, the tiny masses of the light active neutrinos are generated via a three-loop radiative inverse seesaw mechanism, with Dirac and Majorana submatrices arising at one-loop level. To the best of our knowledge, this is the first example of the inverse seesaw mechanism being implemented with both submatrices generated at one- loop level. The model contains a global U(1) X symmetry which, after its spontaneous breaking, allows for the stabilization of the Dark Matter (DM) candidates. We show that the electroweak precision observables, the electron and muon anomalous magnetic moments as well as the Charged Lepton Flavor Violating decays, μ → eγ, are consistent with the current experimental limits. In addition, we analyze the implications of the model for the 95 GeV diphoton excess recently reported by the CMS collaboration and demonstrate that such anomaly could be easily accommodated. Finally, we discuss qualitative aspects of DM in the considered model. © 2023, The Author(s).
Fast rotating blue stragglers prefer loose clusters
(Nature Research, 0023-12) Ferraro, Francesco R; Mucciarelli, Alessio; Lanzoni, Barbara; Pallanca, Cristina; Cadelano, Mario; Billi, Alex; Sills, Alison; Vesperini, Enrico; Dalessandro, Emanuele; Beccari, Giacomo; Monaco, Lorenzo; Mateo, Mario
Blue stragglers are anomalously luminous core hydrogen-burning stars formed through mass-transfer in binary/triple systems and stellar collisions. Their physical and evolutionary properties are largely unknown and unconstrained. Here we analyze 320 high-resolution spectra of blue stragglers collected in eight galactic globular clusters with different structural characteristics and show evidence that the fraction of fast rotating blue stragglers (with rotational velocities larger than 40 km/s) increases for decreasing central density of the host system. This trend suggests that fast spinning blue stragglers prefer low-density environments and promises to open an unexplored route towards understanding the evolutionary processes of these stars. Since large rotation rates are expected in the early stages of both formation channels, our results provide direct evidence for recent blue straggler formation activity in low-density environments and put strong constraints on the timescale of the collisional blue straggler slow-down processes. © 2023, The Author(s).
Designing an Optimal Kilonova Search Using DECam for Gravitational-wave Events
(Institute of Physics, 0024) Bom C.R.; Annis J; Garcia A.; Palmese A.; Sherman N.; Soares-Santos M.; Santana-Silva L; Morgan R.; Bechtol K; Davis T.; Diehl H.T.; Allam S.S.
We address the problem of optimally identifying all kilonovae detected via gravitational-wave emission in the upcoming LIGO/Virgo/KAGRA observing run, O4, which is expected to be sensitive to a factor of ∼7 more binary neutron star (BNS) alerts than previously. Electromagnetic follow-up of all but the brightest of these new events will require >1 m telescopes, for which limited time is available. We present an optimized observing strategy for the DECam during O4. We base our study on simulations of gravitational-wave events expected for O4 and wide-prior kilonova simulations. We derive the detectabilities of events for realistic observing conditions. We optimize our strategy for confirming a kilonova while minimizing telescope time. For a wide range of kilonova parameters, corresponding to a fainter kilonova compared to GW170817/AT 2017gfo, we find that, with this optimal strategy, the discovery probability for electromagnetic counterparts with the DECam is ∼80% at the nominal BNS gravitational-wave detection limit for O4 (190 Mpc), which corresponds to an ∼30% improvement compared to the strategy adopted during the previous observing run. For more distant events (∼330 Mpc), we reach an ∼60% probability of detection, a factor of ∼2 increase. For a brighter kilonova model dominated by the blue component that reproduces the observations of GW170817/AT 2017gfo, we find that we can reach ∼90% probability of detection out to 330 Mpc, representing an increase of ∼20%, while also reducing the total telescope time required to follow up events by ∼20%. © 2024. The Author(s). Published by the American Astronomical Society
Observation of quantum entanglement with top quarks at the ATLAS detector
(Nature Research, 0024-09) Zwalinski L.; Zou W; Zormpa O; Zorbas T.G; Zoch K; Zoccoli A; Živković L.; Ziolkowski M.; Zinsser J.; Zimine N.I.; Zhukov K.; Zhuang X
Entanglement is a key feature of quantum mechanics1–3, with applications in fields such as metrology, cryptography, quantum information and quantum computation4–8. It has been observed in a wide variety of systems and length scales, ranging from the microscopic9–13 to the macroscopic14–16. However, entanglement remains largely unexplored at the highest accessible energy scales. Here we report the highest-energy observation of entanglement, in top–antitop quark events produced at the Large Hadron Collider, using a proton–proton collision dataset with a centre-of-mass energy of √s = 13 TeV and an integrated luminosity of 140 inverse femtobarns (fb)−1 recorded with the ATLAS experiment. Spin entanglement is detected from the measurement of a single observable D, inferred from the angle between the charged leptons in their parent top- and antitop-quark rest frames. The observable is measured in a narrow interval around the top–antitop quark production threshold, at which the entanglement detection is expected to be significant. It is reported in a fiducial phase space defined with stable particles to minimize the uncertainties that stem from the limitations of the Monte Carlo event generators and the parton shower model in modelling top-quark pair production. The entanglement marker is measured to be D = −0.537 ± 0.002 (stat.) ± 0.019 (syst.) for 340GeV
Modified Heisenberg Commutation Relations and the Infinite-Square Well Potential: Some Simple Consequences
(Multidisciplinary Digital Publishing Institute (MDPI), 0024-10) González, Mauricio Contreras; Herrera, Roberto Ortiz; Gonzalez, José Mauricio
We explore some consequences of modifying the usual Heisenberg commutation relations of two simple systems: first, the one-dimensional quantum system given by the infinite square-well potential, and second, the case of a gas of N non-interacting particles in a box of volume V, which permit obtaining analytical solutions. We analyse two possible cases of modified Heisenberg commutation relations: one with a linear and non-linear dependence on the position and another with a linear and quadratic dependence on the momentum. We determine the eigenfunctions, probability densities, and energy eigenvalues for the one-dimensional square well for both deformation cases. For linear and non-linear x deformation dependence, the wave functions and energy levels change substantially when the weight factor associated with the modification term increases. Here, the energy levels are rescaled homogeneously. Instead, for linear and quadratic momentum p deformation dependence, the changes in the energy spectrum depend on the energy level. However, the probability densities are the same as those without any modification. For the non-interacting gas, the position deformation implies that the ideal gas state equation is modified, acquiring the form of a virial expansion in the volume, whereas the internal energy is unchanged. Instead, the ideal gas state equation remains unchanged at the lowest order in (Formula presented.) for the momentum modification case. However, the temperature modifies the internal energy at the lowest order in (Formula presented.). Thus, this study indicates that gravity could generate forces on particles by modifying the Heisenberg commutation relations. Therefore, gravitation could be the cause of the other three forces of nature. © 2024 by the authors.
The young exoplanetary system TOI-4562: Confirming the presence of a third body in the system
(LETTER TO THE EDITOR, 0024-10-09) Fermiano, V; Saito, RK; Ivanov, VD; Caceres, C; Almeida, LA; Aires, J; Beamin, JC; Minniti, D; Ferreira, T; Andrade, L; Borges, BW; de Almeida, L; Jablonski, F; Schlindwein, W
Young planetary systems represent an opportunity to investigate the early stages of (exo)planetary formation because the gravitational interactions have not yet significantly changed the initial configuration of the system. Aims. TOI-4562 b is a highly eccentric temperate Jupiter analogue orbiting a young F7V-type star of < 700 Myr in age with an orbital period of Porb similar to 225 days and an eccentricity of e = 0.76, and is one of the largest known exoplanets to have formed in situ. Methods. We observed a new transit of TOI-4562 b using the 0.6-m Zeiss telescope at the Pico dos Dias Observatory (OPD/LNA) in Minas Gerais, Brazil, and combine our data with Transiting Exoplanet Survey Satellite (TESS) and archive data, with the aim being to improve the ephemerides of this interesting system. Results. The O - C diagram for the new ephemeris is consistent with the presence of a giant planet in an outer orbit around TOI-4562. TOI-4562 c is a planet with a mass of M = 5.77 MJup, an orbital period of Porb = 3990 days, and a semi-major axis of a = 5.219 AU. Conclusions. We report the discovery of TOI-4562 c, the exoplanet with the longest orbital period discovered to date via the transit timing variation (TTV) method. The TOI-4562 system is in the process of violent evolution with intense dynamical changes - judging by its young age and high eccentricity - and is therefore a prime target for studies of formation and evolution of planetary systems.
Fermion dark matter in the vector scotogenic model: a survey of signatures
(Springer Nature, 0024-12) Areyuna, Paulo C; Zamora-Saa, Jilberto; Zerwekh, Alfonso R.
In this work, we have studied the vector scotogenic model in the context of the dark matter problem. Due to unitarity considerations, we have focused on the scenario with fermion dark matter, finding out that co-annihilations play a fundamental role in achieving dark matter relic abundance. Moreover, the coannihilation effects allow to separate the parameter space into two regions with different phenomenology. In addition, we have studied the detection prospects of these regions separately, focusing on signatures that can appear in lepton flavor violating decays, indirect and direct searches, and the production of these new particles at collider facilities. © The Author(s) 2024.
The Milky Way accretion history compared to cosmological simulations: From bulge formation to dwarf galaxy infall
(EDP Sciences, 0024-12) Hammer F; Jiao Y.J.; Mamon G.A; Yang Y.B; Akib I.; Amram P.; Wang H.F.; Wang J.L; Chemin L.
Galactic halos are known to grow hierarchically, inside out. This implies a correlation between the infall lookback time of satellites and their binding energy. Cosmological simulations predict a linear relation between the infall lookback time and the logarithm of the binding energy, with a small scatter. Gaia measurements of the bulk proper motions of globular clusters and dwarf satellites of the Milky Way are sufficiently accurate to establish the kinetic energies of these systems. Assuming the gravitational potential of the Milky Way, we can deduce the binding energies of the dwarf satellites and those of the galaxies that were previously accreted by the Milky Way. This can be compared to cosmological simulations for the first time. The relation of the infall lookback time versus binding energy we found in a cosmological simulation matches that for the early accretion events when the simulated total Milky Way mass within 21 kpc was rescaled to 2 1011 M. This agrees well with previous estimates from globular cluster kinematics and from the rotation curve. However, the vast majority of the dwarf galaxies are clear outliers to this rescaled relation, unless they are very recent infallers. In other words, the very low binding energies of most dwarf galaxies compared to Sgr and previous accreted galaxies suggests that most of them were accreted much later than 8 or even 5 Gyr ago. We also found that the subhalo systems in some cosmological simulations are too dynamically hot when they are compared to identified Milky Way substructures. This leads to an overestimated impact of satellites on the Galaxy rotation curve. © 2024 EDP Sciences. All rights reserved.
Decoding the formation of hammerhead ion populations observed by Parker Solar Probe
(EDP Sciences, 0024-12) Shaaban, Shaaban M; Lazar M; López R.A.; Yoon P.H.; Poedts S
Context. In situ observations by the Parker Solar Probe (PSP) have revealed new properties of the proton velocity distributions (VDs), including hammerhead features that suggest a non-isotropic broadening of the beams. Aims. The present work proposes a very plausible explanation for the formation of hammerhead proton populations through the action of a proton firehose-like instability triggered by the proton beam. Methods. We investigated a self-generated firehose-like instability driven by the relative drift of ion populations using a simplified moment-based quasi-linear (QL) theory. While simpler and faster than advanced numerical simulations, this toy model provided rapid insights and concisely highlighted the role of plasma micro-instabilities in relaxing the observed anisotropies of particle VDs in the solar wind and space plasmas. Results. The QL theory proposed here shows that the resulting transverse waves are right-hand polarized and have two consequences on the protons: (i) They reduce the relative drift between the beam and the core, but above all, (ii) they induce a strong perpendicular temperature anisotropy specific to the observed hammerhead ion beam. Moreover, the long-run QL results suggest that these hammerhead distributions are rather transitory states that are still subject to relaxation mechanisms, in which instabilities such as the one discussed here are very likely involved. This foundational work motivates future detailed studies using advanced methods. © The Authors 2024.
Documentary Analysis of Hypericum perforatum (St. John’s Wort) and Its Effect on Depressive Disorders
(Multidisciplinary Digital Publishing Institute (MDPI), 0024-12) Otero, María Carolina; Ceric, Francisco; Miranda-Rojas, Sebastián; Carreño, Carolina; Atala, Cristian; Ramírez-Barrantes, Ricardo; Gordillo-Fuenzalida, Felipe
Hypericum perforatum, also known as St. John’s Wort, pericon, or yellow grass, is known for its antidepressant potential. It could represent a natural alternative to current pharmacological antidepressant treatments, which have a high incidence of side effects in patients and therefore lead to early dropouts. Through a bibliographic revision of clinical trials and information collected from scientific articles during the first period of 2020, we aimed to evaluate whether its administration could be beneficial in the treatment of mild-to-moderate depression, with fewer side effects compared to synthetic drugs. Among the main components, hypericin and hyperforin have been related to the observed antidepressant activity; therefore, their possible mechanism of action was reviewed and highlighted. Furthermore, patients receiving Hypericum extracts were less likely to withdraw from studies because of adverse effects compared to those receiving older standard antidepressants. This review aims to provide suggestions for an alternative treatment of mild-to-moderate depression disorder under the supervision of a medical doctor, since, although it appears to be a potentially efficient treatment with a low presence of adverse effects in comparison to synthetic antidepressants, it might also interact with other medications and lead to therapeutic failures if misused for self-medication. © 2024 by the authors.
The fast rise of the unusual type IIL/IIb SN 2018ivc
(EDP Sciences, 0024-12) Reguitti A; Dastidar R.; Pignata G; Maeda K.; Moriya T.J.; Kuncarayakti H.; Rodríguez Ó; Bersten M.; Anderson J.P.; Charalampopoulos P.; Fraser M; Gromadzki M.
We present an analysis of the photometric and spectroscopic dataset of the type II supernova (SN) 2018ivc in the nearby (10 Mpc) galaxy Messier 77. Thanks to our high-cadence data, we observed the SN rising very rapidly by nearly three magnitudes in five hours (or 18 mag d- 1). The r-band light curve presents four distinct phases: the maximum light, which was reached in just one day, followed by a first, rapid linear decline and a short-duration plateau. Finally, the long, slower linear decline lasted for one year. Thanks to the ensuing radio re-brightening, we were able to detect SN 2018ivc four years after the explosion. The early spectra show a blue, nearly featureless continuum, but the spectra go on to evolve rapidly; after about ten days, a prominent Hα line starts to emerge, characterised by a peculiar profile. However, the spectra are heavily contaminated by emission lines from the host galaxy. The He I lines, namely λλ5876,7065, are also strong. In addition, strong absorption from the Na I doublet is evident and indicative of a non-negligible internal reddening. From its equivalent width, we derived a lower limit on the host reddening of AV ≲ 1.5 mag. From the Balmer decrement and a match of the B- V colour curve of SN 2018ivc to that of the comparison objects, we obtained a host reddening of AV ≲ 3.0 mag. The spectra are similar to those of SNe II, but with strong He lines. Given the peculiar light curve and spectral features, we suggest SN 2018ivc could be a transitional object between the type IIL and type IIb SNe classes. In addition, we found signs of an interaction with the circum-stellar medium (CSM) in the light curve, also making SN 2018ivc an interacting event. Finally, we modelled the early multi-band light curves and photospheric velocity of SN 2018ivc to estimate the physical parameters of the explosion and CSM. © The Authors 2024.
Candidate ferroelectrics via ab initio high-throughput screening of polar materials
(Nature Research, 0024-12-24) Ricci, Francesco; Reyes-Lillo, Sebastian E; Mack, Stephanie A; Neaton, Jeffrey B
Ferroelectrics are a class of polar and switchable functional materials with diverse applications, from microelectronics to energy conversion. Computational searches for new ferroelectric materials have been constrained by accurate prediction of the polarization and switchability with electric field, properties that, in principle, require a comparison with a nonpolar phase whose atomic-scale unit cell is continuously deformable from the polar ground state. For most polar materials, such a higher-symmetry nonpolar phase does not exist or is unknown. Here, we introduce a general high-throughput workflow that screens polar materials as potential ferroelectrics. We demonstrate our workflow on 1978 polar structures in the Materials Project database, for which we automatically generate a nonpolar reference structure using pseudosymmetries, and then compute the polarization difference and energy barrier between polar and nonpolar phases, comparing the predicted values to known ferroelectrics. Focusing on a subset of 182 potential ferroelectrics, we implement a systematic ranking strategy that prioritizes candidates with large polarization and small polar-nonpolar energy differences. To assess stability and synthesizability, we combine information including the computed formation energy above the convex hull, the Inorganic Crystal Structure Database id number, a previously reported machine learning-based synthesizability score, and ab initio phonon band structures. To distinguish between previously reported ferroelectrics, materials known for alternative applications, and lesser-known materials, we combine this ranking with a survey of the existing literature on these candidates through Google Scholar and Scopus databases, revealing ~130 promising materials uninvestigated as ferroelectric. Our workflow and large-scale high-throughput screening lays the groundwork for the discovery of novel ferroelectrics, revealing numerous candidates materials for future experimental and theoretical endeavors. © 2024, The Author(s).
Black carbon effects and seasonal isotope records in the Godwin‑Austen snowpack and K2 high-altitude camps
(Cambridge University Press, 0025) González-Santacruz, Nicolás; Fernandoy, Francisco; Goto-Azuma, Kumiko; Hirabayashi, Motohiro; Cordero, Raúl; Feron, Sarah; Faria, Sérgio Henrique
This study investigates black carbon (BC) concentrations in the seasonal snowpack on the Godwin-Austen Glacier and in surface snow at K2 Camps 1 and 2 (Karakoram Range), assessing their impact on snowmelt during the 2019 ablation season. Potential BC and moisture sources were identified through back-trajectory analysis and atmospheric reanalyses. Variations in water stable isotopes (δ18O and δ2H) in the snowpack were analysed to confirm its representativeness as a climatic record for the 2018–19 accumulation season. The average BC concentration in the snowpits (12 ng g-1) generated 66 mm w.e. (or 53 mm w.e. excluding the basal zone) of meltwater. Surface snow at K2 Camp 1 showed BC concentrations of 7 ng g-1, consistent with those on the snowpack surface, suggesting it may reflect local BC levels in late February 2019. In contrast, higher concentrations at K2 Camp 2 (26 ng g-1) were potentially linked to expedition activities. © 2025 Cambridge University Press. All rights reserved.
The VISCACHA Survey: XII. SL 2: Age gap cluster in the southwestern Large Magellanic Cloud
(EDP Sciences, 0025) Ferreira, Bernardo P. L.; Dias, Bruno; Santos, João F. C.; Maia, Francisco F. S; Bica, Eduardo; Kerber, Leandro O.; Armond, Tina; Quint, Bruno; Oliveira, Raphael A. P.; Souza, Stefano O.; Fernández-Trincado, José G; Katime Santrich, Orlando
Context. In the Large Magellanic Cloud (LMC), only seven star clusters have been discovered to be older than ~4 Gyr and younger than ~10 Gyr, placing them in what is known as the age gap. Aims. We aim to analyze the photometric data from the VISCACHA survey in the V and I bands to determine, for the first time, the astrophysical parameters of SL 2, revealing that the cluster is indeed situated within the age gap. Methods. We used our newly developed SIESTA code to carry out a statistical isochrone fitting with synthetic color-magnitude diagrams (CMDs) to determine the cluster age, metallicity, distance, color excess, and binary fraction with two grids of stellar evolution models. In addition, the cluster mass was estimated based on its integrated magnitude. Results. The ages obtained from isochrone fitting are compatible with the age gap, amounting to (7.17 ± 0.35) Gyr when using PARSEC-COLIBRI isochrones and (8.02 ± 0.45) Gyr when using MIST. Notably, SL 2 is the first age gap cluster discovered in the southern region of the LMC. The mass of the cluster is considerably smaller than that of the group of older LMC clusters. Conclusions. SL 2 has a comparable metallicity to the other two age gap clusters with similar ages, namely, ESO 121-03 and KMHK 1592, as well as the LMC field star population. While the discovery of a new cluster with such characteristics could be seen as evidence that age gap clusters were formed in situ, the heliocentric distance of SL2 locates it far from the LMC center, akin to the SMC distance. Therefore, the question of its origin, alongside that of other age gap clusters, remains unresolved and open to further investigation. © 2025 EDP Sciences. All rights reserved.
Development of molecularly imprinted polymers for the detection of human chorionic gonadotropin
(Nature Research, 0025) Zubrytė, Radvilė; Mavliutova, Liliia; García, Yadiris; Sullivan, Mark V.; Turner, Nicholas W.; Patitucci, Francesco; Polania, Laura C.; Jiménez, Verónica A; Porter, Robert; Mattsson, Alice; Sellergren, Börje
Diagnostic pregnancy tests are the most widely used immunoassays for home-based use. These tests employ the well-established lateral flow assay (LFA) technique, reminiscent of affinity chromatography relying on the dual action of two orthogonal anti-hCG antibodies. Immunoassays suffer from several drawbacks, including challenges in antibody manufacturing, suboptimal accuracy, and sensitivity to adverse storing conditions. Additionally, LFAs are typically designed for single use, as the LFA technique is non-reusable. An alternative to overcome these drawbacks is to leverage molecularly imprinted polymer (MIP) technology to generate polymer-based hCG-receptors and, subsequently, non-bioreceptor-based tests. Here, we report the development of MIP nanogels for hCG detection, exploiting epitopes and magnetic templates for high-yielding dispersed phase imprinting. The resulting nanogels were designed for orthogonal targeting of two immunogenic epitopes (SV and PQ) and were thoroughly characterized with respect to physical properties, binding affinity, specificity, and sensitivity. Molecular dynamics simulations indicated a pronounced conformational overlap between the templates and the epitopes in the native protein, supporting their suitability for templating cavities for hCG recognition. Quartz crystal microbalance (QCM)-based binding tests and kinetic interaction analysis by surface plasmon resonance (SPR) revealed nanomolar dissociation constants for the MIP nanogels and their corresponding template peptides and low uptake of lutenizing hormone (LH), structurally resembling to hCG. Receptor reusability was demonstrated in the multicycle SPR sensing mode using a low pH regeneration buffer. The results suggest the feasibility of using imprinted nanogels as a class of cost-effective, stable alternatives to natural antibodies for hCG detection. We foresee applications of these binders with respect to reusable pregnancy tests and other hCG-related disease diagnostics. © The Author(s) 2025.
Development of molecularly imprinted polymers for the detection of human chorionic gonadotropin
(Nature Research, 0025) Zubrytė, Radvilė; Mavliutova, Liliia; García, Yadiris; Sullivan, Mark V.; Turner, Nicholas W.; Patitucci, Francesco; Polania, Laura C. d; Jiménez, Verónica A.; Porter, Robert; Mattsson, Alice; Sellergren, Börje b
Diagnostic pregnancy tests are the most widely used immunoassays for home-based use. These tests employ the well-established lateral flow assay (LFA) technique, reminiscent of affinity chromatography relying on the dual action of two orthogonal anti-hCG antibodies. Immunoassays suffer from several drawbacks, including challenges in antibody manufacturing, suboptimal accuracy, and sensitivity to adverse storing conditions. Additionally, LFAs are typically designed for single use, as the LFA technique is non-reusable. An alternative to overcome these drawbacks is to leverage molecularly imprinted polymer (MIP) technology to generate polymer-based hCG-receptors and, subsequently, non-bioreceptor-based tests. Here, we report the development of MIP nanogels for hCG detection, exploiting epitopes and magnetic templates for high-yielding dispersed phase imprinting. The resulting nanogels were designed for orthogonal targeting of two immunogenic epitopes (SV and PQ) and were thoroughly characterized with respect to physical properties, binding affinity, specificity, and sensitivity. Molecular dynamics simulations indicated a pronounced conformational overlap between the templates and the epitopes in the native protein, supporting their suitability for templating cavities for hCG recognition. Quartz crystal microbalance (QCM)-based binding tests and kinetic interaction analysis by surface plasmon resonance (SPR) revealed nanomolar dissociation constants for the MIP nanogels and their corresponding template peptides and low uptake of lutenizing hormone (LH), structurally resembling to hCG. Receptor reusability was demonstrated in the multicycle SPR sensing mode using a low pH regeneration buffer. The results suggest the feasibility of using imprinted nanogels as a class of cost-effective, stable alternatives to natural antibodies for hCG detection. We foresee applications of these binders with respect to reusable pregnancy tests and other hCG-related disease diagnostics. © The Author(s) 2025.
MINCE: III. Detailed chemical analysis of the UVES sample
(EDP Sciences, 0025) Lucertini F.; Sbordone L; Caffau E.; Bonifacio P.; Monaco L.; Cescutti G.; Lallement R; François P; Spitoni E; Hansen C.J.; Korn A.J.; Kučinskas A.
Context. The Measuring at Intermediate Metallicity Neutron-Capture Elements (MINCE) project aims to provide high-quality neutron-capture abundances measurements for several hundred stars at an intermediate metallicity of -2.5 < [Fe/H] < -1.5. This project will shed light on the origin of the neutron-capture elements and the chemical enrichment of the Milky Way. Aims. The goal of this work is to chemically characterize the second sample of the MINCE project and compare the abundances with the galactic chemical evolution model at our disposal. Methods. We performed a standard abundance analysis based on one-dimensional (1D) local thermodynamic equilibrium (LTE) model atmospheres based on high-resolution and high-signal-to-noise-ratio (S/N) spectra from Ultraviolet and Visual Echelle Spectrograph (UVES). Results. We provide the kinematic classification (i.e., thin disk, thick disk, thin-to-thick disk, halo, Gaia Sausage Enceladus, Sequoia) of 99 stars and the atmospheric parameters for almost all stars. We derived the abundances for light elements (from Na to Zn) and neutron-capture elements (Rb, Sr, Y, Zr, Ba, La, Ce, Pr, Nd, Sm, and Eu) for a subsample of 32 stars in the metallicity range of -2.5 < [Fe/H] < -1.00. In the subsample of 32 stars, we identified eight active stars exhibiting (inverse) P-Cygni profile and one Li-rich star, CD 28-11039. We find a general agreement between the chemical abundances and the stochastic model computed for the chemical evolution of the Milky Way halo for elements Mg, Ca, Si, Ti, Sc, Mn, Co, Ni, Zn, Rb, Sr, Y, Zr, Ba, La, and Eu. Conclusions. The MINCE project has already significantly increased the number of neutron-capture elements measurements in the intermediate metallicity range. The results from this sample are in perfect agreement with the previous MINCE sample. The good agreement between the chemical abundances and the chemical evolution model of the Galaxy supports the nucleosynthetic processes adopted to describe the origin of the n-capture elements. © The Authors 2025.
The Gaia Parallax Discrepancy for the Cluster Pismis 19 and Separating δ Scutis from Cepheids
(Institute of Physics, 0025) Majaess, Daniel; Bonatto, Charles J.; Turner, David G; Saito, Roberto K; Minniti, Dante; Moni Bidin, Christian; González-Díaz, Danilo; Alonso-Garcia, Javier; Bono, Giuseppe; Braga, Vittorio F.; Navarro, Maria G; Carraro, Giovanni
Pre-Gaia distances for the open cluster Pismis 19 disagree with Gaia parallaxes. A Two Micron All Sky Survey (2MASS) JKs red clump distance was therefore established for Pismis 19 (2.90 ± 0.15 kpc), which reaffirms that zero-point corrections for Gaia are required. OGLE GD-CEP-1864 is confirmed as a member of Pismis 19 on the basis of DR3 proper motions and its 2MASS+Vista Variables in the Vía Láctea color-magnitude position near the tip of the turnoff. That 0.3 day variable star is likely a δ Scuti rather than a classical Cepheid. The case revealed a pertinent criterion to segregate those two populations in tandem with the break in the Wesenheit Leavitt Law (≃0.5 day). Just shortward of that period discontinuity are δ Scutis, whereas beyond the break lie first overtone classical Cepheids mostly observed beyond the first crossing of the instability strip. © 2025. The Author(s). Published by the American Astronomical Society.
Searching for HI around MHONGOOSE galaxies via spectral stacking
(EDP Sciences, 0025-01-01) Veronese, S; de Blok W J G; Healy J; Kleiner D; Marasco A; Maccagni F M; Kamphuis P; Brinks E; Holwerda B W; Zabel N; Chemin L; Adams E A K
The observed star formation rates of galaxies in the Local Universe suggests that they are replenishing their gas reservoir across cosmic time. Cosmological simulations predict that this accretion of fresh gas can occur in a hot or a cold mode, yet the existence of low column density (∼1017 cm−2) neutral atomic hydrogen (Hi) tracing the cold mode has not been unambiguously confirmed by observations. We present the application of unconstrained spectral stacking to attempt to detect the emission from this Hi in the circumgalactic medium (CGM) and intergalactic medium (IGM) of six nearby star-forming galaxies from the MHONGOOSE sample for which full-depth observations are available. Our stacking procedure consists of a standard spectral stacking algorithm coupled with a one-dimensional spectral line finder designed to extract a reliable signal close to the noise level. In agreement with previous studies, we find that the amount of signal detected outside the Hi disk is much smaller than implied by simulations. Furthermore, the column density limit that we achieve via stacking (∼1017 cm−2) suggests that direct detection of the neutral CGM and IGM component might be challenging in the future, even with the next generation of radio telescopes. © The Authors 2025.
Dark matter fraction derived from the M31 rotation curve
(EDP Sciences, 0025-02) Hammer F.; Yang Y.B.; Amram P.; Chemin L.; Mamon G.A.; Wang J.L.; Akib I.; Jiao Y.J.; Wang H.F.
Mass estimates of a spiral galaxy derived from its rotation curve must account for the galaxy's past accretion history. There are several lines of evidence indicating that M31 experienced a major merger 2 to 3 Gyr ago. In this work, we generated a dynamical model of M31 as a merger remnant that reproduces most of its properties, including from the central bar to the outskirts. The model accounts for M31's past major merger and reproduces the details of its rotation curve, including its 14 kpc bump and the observed increase of velocity beyond 25 kpc. We find non-equilibrium and oscillatory motions in the gas of the merger-remnant outskirts caused by material in a tidal tail returning to the merger remnant. A total dynamical M31 mass of 4.5× 1011 M⊙ within 137 kpc was obtained after scaling it to the observed HI rotation curve. Within this radial distance, we find that 68% of the total dynamical mass is dark. © The Authors 2025.

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