Instituto de Física de Cantabria (CSIC-UC)
Massive galaxy clusters act as prominent strong-lenses. Due to a combination of observational biases, cluster evolution and lensing efficiency, most of the known cluster lenses lie typically at zl0.20.7z_{l}\sim0.2-0.7, with only a few prominent examples at higher redshifts. Here we report a first strong-lensing analysis of the massive galaxy cluster SPT-CL J0546-5345 at a redshift zl=1.07z_l=1.07. This cluster was first detected through the Sunyaev-Zel'dovich effect, with a high estimated mass for its redshift of M200,c=(7.95±0.92)×1014MM_{200,c} = (7.95 \pm 0.92) \times 10^{14}\,M_{\odot}. Using recent JWST/NIRCam and archival HST imaging, we identify at least 10 secure and 6 candidate sets of multiply imaged background galaxies, which we use to constrain the mass distribution in the cluster. We derive effective Einstein radii of θE=18.1±1.8\theta_{E}= 18.1 \pm 1.8 '' for a source at zs=3z_{s}=3, and θE=27.9±2.8\theta_{E}= 27.9 \pm 2.8 '' for a source at zs=9z_{s}=9. The total projected mass within a 200200 kpc radius around the strong-lensing region is M(<200\,\mathrm{kpc}) = (1.9 \pm 0.3) \times 10^{14}\,M_{\odot}. While our results rely on photometric redshifts warranting spectroscopic follow-up, this central mass resembles that of the Hubble Frontier Fields clusters - although SPT-CL J0546-5345 is observed when the Universe was 34\sim 3-4 Gyr younger. Amongst the multiply-imaged sources, we identify a hyperbolic-umbilic-like configuration, and, thanks to its point-like morphology, a possible Active Galactic Nucleus (AGN). If confirmed spectroscopically, it will add to just a handful of other quasars and AGN known to be multiply lensed by galaxy clusters.
Multiply-imaged supernovae (SNe) provide a novel means of constraining the Hubble constant (H0H_0). Such measurements require a combination of precise models of the lensing mass distribution and an accurate estimate of the relative time delays between arrival of the multiple images. Only two multiply-imaged SNe, Refsdal and H0pe, have enabled measurements of H0H_0 thus far. Here we detail the third such measurement for SN Encore, a z=1.95z=1.95 SNIa discovered in JWST/NIRCam imaging. We measure the time delay, perform simulations of additional microlensing and millilensing systematics, and combine with the mass models of Suyu et al. in a double-blind analysis to obtain our H0H_0 constraint. Our final time-delay measurement is Δt1b,1a=39.83.3+3.9\Delta t_{1b,1a}=-39.8_{-3.3}^{+3.9} days, which is combined with seven lens models weighted by the likelihood of the observed multiple image positions for a result of H0=66.98.1+11.2kms1Mpc1H_0=66.9_{-8.1}^{+11.2} \rm{km} \rm{s}^{-1}\rm{Mpc}^{-1}. The uncertainty on this measurement could be improved significantly if template imaging is obtained. Remarkably, a sibling to SN Encore (SN "Requiem") was discovered in the same host galaxy, making the MACS J0138.0-2155 cluster the first system known to produce more than one observed multiply-imaged SN. SN Requiem has a fourth image that is expected to appear within a few years, providing an unprecedented decade-long baseline for time-delay cosmography and an opportunity for a high-precision joint estimate of H0H_0.
Predictions for the Higgs masses are a distinctive feature of supersymmetric extensions of the Standard Model, where they play a crucial role in constraining the parameter space. The discovery of a Higgs boson and the remarkably precise measurement of its mass at the LHC have spurred new efforts aimed at improving the accuracy of the theoretical predictions for the Higgs masses in supersymmetric models. The "Precision SUSY Higgs Mass Calculation Initiative" (KUTS) was launched in 2014 to provide a forum for discussions between the different groups involved in these efforts. This report aims to present a comprehensive overview of the current status of Higgs-mass calculations in supersymmetric models, to document the many advances that were achieved in recent years and were discussed during the KUTS meetings, and to outline the prospects for future improvements in these calculations.
We explore for the first time the possibility of detecting lensed star transients in galaxy-galaxy strong lensing systems upon repeated, deep imaging using the {\it James-Webb Space Telescope} ({\it JWST}). Our calculation predicts that the extremely high recent star formation rate of 100Myr1\sim 100\,M_{\odot}\textrm{yr}^{-1} over the last 50 Myr (not accounting for image multiplicity) in the ``Cosmic Horseshoe'' lensed system (z=2.381z = 2.381) generates many young, bright stars, of which their large abundance is expected to lead to a detection rate of 60\sim 60 transients per pointing in {\it JWST} observations with a 5σ5\sigma limiting magnitude of 29mAB\sim 29\,m_{AB}. With the high expected detection rate and little room for uncertainty for the lens model compared with cluster lenses, our result suggests that the Cosmic Horseshoe could be an excellent tool to test the nature of Dark Matter based on the spatial distribution of transients, and can be used to constrain axion mass if Dark Matter is constituted of ultra-light axions. We also argue that the large distance modulus of 46.5\sim46.5\,mag at z2.4z \approx 2.4 can act as a filter to screen out less massive stars as transients and allow one to better constrain the high-mass end of the stellar initial mass function based on the transient detection rate. Follow-up {\it JWST} observations of the Cosmic Horseshoe with would allow one to better probe the nature of Dark Matter and the star formation properties, such as the initial mass function at the cosmic noon, via lensed star transients.
Seven distinct lens models of the galaxy cluster PLCK G165.7+67.0 systematically over-predict the absolute magnifications of the lensed Type Ia supernova H0pe. This overestimation results in a reconstructed intrinsic brightness for SN H0pe that is consistently >1 magnitude (approximately 4.5σ) higher than expected from standard cosmological models.
El Gordo (ACT-CL J0102-4915) is a massive galaxy cluster with two major mass components at redshift z=0.87z=0.87. Using SED fitting results from JWST/NIRCam photometry, the fraction of quenched galaxies in this cluster was measured in two bins of stellar mass: 9<\log{({M_*}/\mathrm{M}_{\odot})}<10 and 10\leq\log{({M_*}/\mathrm{M}_{\odot})}<12. While there is no correlation between the quenched fraction and angular separation from the cluster's overall center of mass, there is a correlation between the quenched fraction and angular separation from the center of the nearest of the two mass components for the less-massive galaxies. This suggests that environmental quenching processes are in place at z1z\sim1, and that dwarf galaxies are more affected by those processes than massive galaxies.
Global frequentist fits to the CMSSM and NUHM1 using the MasterCode framework are updated to include the public results of searches for supersymmetric signals using \sim 1/fb of LHC data recorded by ATLAS and CMS and \sim 0.3/fb of data recorded by LHCb. We also include the constraints imposed by the electroweak precision and B-physics observables, the cosmological dark matter density and the XENON100 search for spin-independent dark matter scattering. Finally we also investigate the impact of a possible Higgs signal around 125 GeV. The various constraints set new bounds on the parameter space of the CMSSM and the NUHM1. We discuss the impact of the new results from SUSY and Higgs searches for these bounds and analyze the impact for a future liner e^+e^- collider.
Stellar disk truncations, also referred to as galaxy edges, are key indicators of galactic size, determined by the radial location of the gas density threshold for star formation. Accurately measuring galaxy sizes for millions of galaxies is essential for understanding the physical processes driving galaxy evolution over cosmic time. In this study, we aim to explore the potential of the Segment Anything Model (SAM), a foundation model designed for image segmentation, to automatically identify disk truncations in galaxy images. With the Euclid Wide Survey poised to deliver vast datasets, our goal is to assess SAM's capability to measure galaxy sizes in a fully automated manner. SAM was applied to a labeled dataset of 1,047 disk-like galaxies with M>1010MM_* > 10^{10} M_{\odot} at redshifts up to z1z \sim 1, sourced from the HST CANDELS fields. We 'euclidized' the HST galaxy images by creating composite RGB images, using the F160W (H-band), F125W (J-band), and F814W + F606W (I-band + V-band) HST filters, respectively. Using these processed images as input for SAM, we retrieved various truncation masks for each galaxy image under different configurations of the input data. We find excellent agreement between the galaxy sizes identified by SAM and those measured manually (i.e., by using the radial positions of the stellar disk edges in galaxy light profiles), with an average deviation of approximately 3%3\%. This error reduces to about 1%1\% when excluding problematic cases. Our results highlight the strong potential of SAM for detecting disk truncations and measuring galaxy sizes across large datasets in an automated way. SAM performs well without requiring extensive image preprocessing, labeled training datasets for truncations (used only for validation), fine-tuning, or additional domain-specific adaptations such as transfer learning.
We present a spatially resolved analysis of four star-forming galaxies at $z = 4.44-5.64$ using data from the JWST PRIMER and ALMA-CRISTAL surveys to probe the stellar and inter-stellar medium properties on the sub-kpc scale. In the 15μm1-5\,\mu{\rm m} JWST NIRCam imaging we find that the galaxies are composed of multiple clumps (between 22 and 8\sim 8) separated by 5kpc\simeq 5\,{\rm kpc}, with comparable morphologies and sizes in the rest-frame UV and optical. Using BAGPIPES to perform pixel-by-pixel SED fitting to the JWST data we show that the SFR (25M/yr\simeq 25\,{\rm M}_{\odot}/{\rm yr}) and stellar mass (${\rm log}_{10}(M_{\star}/{\rm M}_{\odot}) \simeq 9.5$) derived from the resolved analysis are in close (0.3dex \lesssim 0.3\,{\rm dex}) agreement with those obtained by fitting the integrated photometry. In contrast to studies of lower-mass sources, we thus find a reduced impact of outshining of the older (more massive) stellar populations in these normal z5z \simeq 5 galaxies. Our JWST analysis recovers bluer rest-frame UV slopes (β2.1\beta \simeq -2.1) and younger ages (100Myr\simeq 100\,{\rm Myr}) than archival values. We find that the dust continuum from ALMA-CRISTAL seen in two of these galaxies correlates, as expected, with regions of redder rest-frame UV slopes and the SED-derived AVA_{\rm V}, as well as the peak in the stellar mass map. We compute the resolved IRX-β\beta relation, showing that the IRX is consistent with the local starburst attenuation curve and further demonstrating the presence of an inhomogeneous dust distribution within the galaxies. A comparison of the CRISTAL sources to those from the FirstLight zoom-in simulation of galaxies with the same MM_{\star} and SFR reveals similar age and colour gradients, suggesting that major mergers may be important in the formation of clumpy galaxies at this epoch.
Polarized foreground emission from the Galaxy is one of the biggest challenges facing current and upcoming cosmic microwave background (CMB) polarization experiments. We develop new models of polarized Galactic dust and synchrotron emission at CMB frequencies that draw on the latest observational constraints, that employ the ``polarization fraction tensor'' framework to couple intensity and polarization in a physically motivated way, and that allow for stochastic realizations of small-scale structure at sub-arcminute angular scales currently unconstrained by full-sky data. We implement these models into the publicly available Python Sky Model (PySM) software and additionally provide PySM interfaces to select models of dust and CO emission from the literature. We characterize the behavior of each model by quantitatively comparing it to observational constraints in both maps and power spectra, demonstrating an overall improvement over previous PySM models. Finally, we synthesize models of the various Galactic foreground components into a coherent suite of three plausible microwave skies that span a range of astrophysical complexity allowed by current data.
Strong gravitational magnifications enable to detect faint background sources, resolve their internal structures, and even identify individual stars in distant galaxies. Highly magnified individual stars allow various applications, including studies of stellar populations in distant galaxies and constraining dark matter structures in the lensing plane. However, these applications have been hampered by the small number of individual stars observed, as typically one or a few stars are identified from each distant galaxy. Here, we report the discovery of more than 40 microlensed stars in a single galaxy behind Abell 370 at redshift of 0.725 when the Universe was half of its current age (dubbed ``the Dragon arc''), using James Webb Space Telescope (JWST) observations with the time-domain technique. These events are found near the expected lensing critical curves, suggesting that these are magnified stars that appear as transients from intracluster stellar microlenses. Through multi-wavelength photometry, we constrain stellar types and find that many of them are consistent with red giants/supergiants magnified by factors of hundreds. This finding reveals an unprecedented high occurrence of microlensing events in the Dragon arc, and proves that {\it JWST}'s time-domain observations open up the possibility of conducting statistical studies of high-redshift stars.
Overcoming both modeling and computational challenges, we present, for the first time, the extended surface-brightness distribution model of a strongly-lensed source in a complex galaxy-cluster-scale system. We exploit the high-resolution Hubble Space Telescope (HST) imaging and extensive Multi Unit Spectroscopic Explorer spectroscopy to build an extended strong-lensing model, in a full multi-plane formalism, of SDSS J1029+2623, a lens cluster at z=0.588z = 0.588 with three multiple images of a background quasar (z=2.1992z = 2.1992). Going beyond typical cluster strong-lensing modeling techniques, we include as observables both the positions of 26 pointlike multiple images from seven background sources, spanning a wide redshift range between 1.02 and 5.06, and the extended surface-brightness distribution of the strongly-lensed quasar host galaxy, over 78000\sim78000 HST pixels. In addition, we model the light distribution of seven objects, angularly close to the strongly-lensed quasar host, over 9300\sim9300 HST pixels. Our extended lens model reproduces well both the observed intensity and morphology of the quasar host galaxy in the HST F160W band (with a 0''.03 pixel scale). The reconstructed source shows a single, compact, and smooth surface-brightness distribution, for which we estimate an intrinsic magnitude of 23.3 ±\pm 0.1 in the F160W band and a half-light radius of (2.39 ±\pm 0.03) kpc. The increased number of observables enables the accurate determination of the total mass of line-of-sight halos lying angularly close to the extended arc. This work paves the way for a new generation of galaxy cluster strong-lens models, where additional, complementary lensing observables are directly incorporated as model constraints.
We use MasterCode to perform a frequentist analysis of the constraints on a phenomenological MSSM model with 11 parameters, the pMSSM11, including constraints from ~ 36/fb of LHC data at 13 TeV and PICO, XENON1T and PandaX-II searches for dark matter scattering, as well as previous accelerator and astrophysical measurements, presenting fits both with and without the (g2)μ(g-2)_{\mu} constraint. The pMSSM11 is specified by the following parameters: 3 gaugino masses M1,2,3M_{1,2,3}, a common mass for the first-and second-generation squarks mq~m_{\tilde{q}} and a distinct third-generation squark mass mq~3m_{\tilde{q}_3}, a common mass for the first-and second-generation sleptons ml~m_{\tilde l} and a distinct third-generation slepton mass mτ~m_{\tilde \tau}, a common trilinear mixing parameter AA, the Higgs mixing parameter μ\mu, the pseudoscalar Higgs mass MAM_A and tanβ\tan\beta. In the fit including (g2)μ(g-2)_{\mu}, a Bino-like χ~10\tilde\chi^0_1 is preferred, whereas a Higgsino-like χ~10\tilde \chi^0_1 is favoured when the (g2)μ(g-2)_{\mu} constraint is dropped. We identify the mechanisms that operate in different regions of the pMSSM11 parameter space to bring the relic density of the lightest neutralino, χ~10\tilde\chi^0_1, into the range indicated by cosmological data. In the fit including (g2)μ(g-2)_{\mu}, coannihilations with χ~20\tilde \chi^0_2 and the Wino-like χ~1±\tilde\chi^{\pm}_1 or with nearly-degenerate first- and second-generation sleptons are favoured, whereas coannihilations with the χ~20\tilde \chi^0_2 and the Higgsino-like χ~1±\tilde\chi^{\pm}_1 or with first- and second-generation squarks may be important when the (g2)μ(g-2)_{\mu} constraint is dropped. Prospects remain for discovering strongly-interacting sparticles at the LHC as well as for discovering electroweakly-interacting sparticles at a future linear e+ee^+ e^- collider such as the ILC or CLIC.
HiggsSignals is a Fortran90 computer code that allows to test the compatibility of Higgs sector predictions against Higgs rates and masses measured at the LHC or the Tevatron. Arbitrary models with any number of Higgs bosons can be investigated using a model-independent input scheme based on HiggsBounds. The test is based on the calculation of a chi-squared measure from the predictions and the measured Higgs rates and masses, with the ability of fully taking into account systematics and correlations for the signal rate predictions, luminosity and Higgs mass predictions. It features two complementary methods for the test. First, the peak-centered method, in which each observable is defined by a Higgs signal rate measured at a specific hypothetical Higgs mass, corresponding to a tentative Higgs signal. Second, the mass-centered method, where the test is evaluated by comparing the signal rate measurement to the theory prediction at the Higgs mass predicted by the model. The program allows for the simultaneous use of both methods, which is useful in testing models with multiple Higgs bosons. The code automatically combines the signal rates of multiple Higgs bosons if their signals cannot be resolved by the experimental analysis. We compare results obtained with HiggsSignals to official ATLAS and CMS results for various examples of Higgs property determinations and find very good agreement. A few examples of HiggsSignals applications are provided, going beyond the scenarios investigated by the LHC collaborations. For models with more than one Higgs boson we recommend to use HiggsSignals and HiggsBounds in parallel to exploit the full constraining power of Higgs search exclusion limits and the measurements of the signal seen at around 125.5 GeV.
Device simulation plays a crucial role in complementing experimental device characterisation by enabling deeper understanding of internal physical processes. However, for simulations to be trusted, experimental validation is essential to confirm the accuracy of the conclusions this http URL the framework of semiconductor detector characterisation, one powerful tool for such validation is the Two Photon Absorption - Transient Current Technique (TPA-TCT), which allows for highly precise, three-dimensional spatially-resolved characterisation of semiconductor detectors. In this work, the TCAD framework Synopsys Sentaurus is used to simulate depth-resolved TPA-TCT data for both p-type pad detectors (PINs) and Low Gain Avalanche Detectors (LGADs). The simulated data are compared against experimentally measured TPA-TCT results. Through this comparison, it is demonstrated that TCAD simulations can reproduce the TPA-TCT measurements, providing valuable insights into the TPA-TCT itself. Another significant outcome of this study is the successful simulation of the gain reduction mechanism, which can be observed in LGADs with increasing densities of excess charge carriers. This effect is demonstrated in an p-type LGAD with a thickness of approximately 286 um. The results confirm the ability of TCAD to model the complex interaction between carrier dynamics and device gain.
LHC searches for non-standard Higgs bosons decaying into tau lepton pairs constitute a sensitive experimental probe for physics beyond the Standard Model (BSM), such as Supersymmetry (SUSY). Recently, the limits obtained from these searches have been presented by the CMS collaboration in a nearly model-independent fashion - as a narrow resonance model - based on the full 8 TeV dataset. In addition to publishing a 95% C.L. exclusion limit, the full likelihood information for the narrow resonance model has been released. This provides valuable information that can be incorporated into global BSM fits. We present a simple algorithm that maps an arbitrary model with multiple neutral Higgs bosons onto the narrow resonance model and derives the corresponding value for the exclusion likelihood from the CMS search. This procedure has been implemented into the public computer code HiggsBounds (version 4.2.0 and higher). We validate our implementation by cross-checking against the official CMS exclusion contours in three Higgs benchmark scenarios in the Minimal Supersymmetric Standard Model (MSSM), and find very good agreement. Going beyond validation, we discuss the combined constraints of the tau tau search and the rate measurements of the SM-like Higgs at 125 GeV in a recently proposed MSSM benchmark scenario, where the lightest Higgs boson obtains SM-like couplings independently of the decoupling of the heavier Higgs states. Technical details for how to access the likelihood information within HiggsBounds are given in the appendix. The program is available at this http URL
In this paper we explore the scientific synergies between Athena and some of the key multi-messenger facilities that should be operative concurrently with Athena. These facilities include LIGO A+, Advanced Virgo+ and future detectors for ground-based observation of gravitational waves (GW), LISA for space-based observations of GW, IceCube and KM3NeT for neutrino observations, and CTA for very high energy observations. These science themes encompass pressing issues in astrophysics, cosmology and fundamental physics such as: the central engine and jet physics in compact binary mergers, accretion processes and jet physics in Super-Massive Binary Black Holes (SMBBHs) and in compact stellar binaries, the equation of state of neutron stars, cosmic accelerators and the origin of Cosmic Rays (CRs), the origin of intermediate and high-Z elements in the Universe, the Cosmic distance scale and tests of General Relativity and the Standard Model. Observational strategies for implementing the identified science topics are also discussed. A significant part of the sources targeted by multi-messenger facilities is of transient nature. We have thus also discussed the synergy of \textsl{Athena} with wide-field high-energy facilities, taking THESEUS as a case study for transient discovery. This discussion covers all the Athena science goals that rely on follow-up observations of high-energy transients identified by external observatories, and includes also topics that are not based on multi-messenger observations, such as the search for missing baryons or the observation of early star populations and metal enrichment at the cosmic dawn with Gamma-Ray Bursts (GRBs).
Stacking the public Planck CMB temperature maps (NILC, SMICA, SEVEM, Commander) on galaxy clusters from Planck catalogues reveals substantial residual contamination from thermal Sunyaev-Zeldovich (tSZ) emission. Unexpectedly, stacking "tSZ-free" CMB maps, like the Planck SMICA-noSZ or Constrained ILC (CILC) maps, still shows noticeable residual contamination from galaxy clusters. We demonstrate that this persisting residual stems from neglected relativistic SZ (rSZ) corrections in the CMB map estimation. Employing a component-separation method specifically designed for the rSZ effect on Planck data, we map the rSZ first-order moment field $y(T_{\rm e}-\bar{T}_{\rm e})$ over the sky for different pivot temperatures Tˉe\bar{T}_{\rm e} ranging from 22 to 1010 keV. Stacking these $y(T_{\rm e}-\bar{T}_{\rm e})$-maps on Planck clusters exhibits either an intensity decrement or increment at the centre, contingent upon whether Tˉe\bar{T}_{\rm e} is above or below the ensemble-averaged cluster temperature TeT_{\rm e}. For the pivot value Tˉe=5\bar{T}_{\rm e}=5 keV, a vanishing intensity is observed in the stacked Planck y(TeTˉe)y(T_{\rm e}-\bar{T}_{\rm e})-map, enabling us to infer the average gas temperature of Te5T_{\rm e}\simeq 5 keV for Planck clusters. Building upon this finding, we revisit the Planck tSZ-free CMB map by deprojecting the complete rSZ emission using CILC, assuming an rSZ spectrum with Te=5T_{\rm e} = 5 keV. Our new, rSZ-free Planck CMB map, when stacked on clusters, shows a clear cancellation of residual SZ contamination in contrast to prior (non-relativistic) tSZ-free Planck CMB maps. Our map-based approach provides compelling evidence for an average temperature of the Planck galaxy clusters of Te=4.9±2.6T_{\rm e} = 4.9 \pm 2.6 keV using the rSZ effect.
Gravitational lensing by galaxy clusters can create extreme magnification near the cluster caustics, thereby enabling detection of individual luminous stars in high-redshift background galaxies. Those stars can include non-explosive standard candles such as Cepheid variables, carbon stars in the asymptotic giant branch, and stars at the tip of the red-giant branch out to z1z\lesssim1. A large number of such detections, combined with modeling of the magnification affecting these stars (including microlensing), opens the door to extending the distance range of these standard candles by two orders of magnitude, thereby providing a check on the distances derived from supernovae. Practical measurement of a distance modulus depends on measuring the apparent magnitude of a ``knee feature'' in the lensed luminosity function due to the great abundance of red-giant-branch stars just below the luminosity of the tip of the red-giant branch. As a bonus, strongly lensed stars detected in deep exposures also provide a robust method of mapping small dark-matter substructures, detections of which also cluster around the critical curves of small-scale dark matter halos.
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