arXiv subjects

Joaquin González-Nuevo

Publications and source records attributed to Joaquin González-Nuevo.

7 recordsLinked to original sources

arXiv2026

Breathless BEARS: [O$_{\rm \,III}$] 88$μ$m Emission of Dusty Star-Forming Galaxies at $z = 3-4$

We present [O$_{\rm \,III}$] 88$μ$m observations towards four ${\it Herschel}$-selected dusty star-forming galaxies (DSFGs; log$_{10}$ $μ$L$_{\rm IR}$/L$_{\odot}$ = 13.5 - 14 at $z = 2.9 - 4$) using the Atacama Compact Array (ACA) in Bands 9 and 10. We detect [O$_{\rm \,III}$] emission in all four targets at >3$σ$, finding line luminosity ratios ($L_{\rm [O_{\rm \,III}]}$ / L$_{\rm IR}$ = 10$^{-4.2}$ to 10$^{-3}$) similar to local spiral galaxies, and an order of magnitude lower when compared with local dwarf galaxies as well as high-redshift Lyman-break galaxies. Using the short-wavelength capabilities of the ACA, these observations bridge the populations of galaxies with [O$_{\rm \,III}$] emission at low redshift from space missions and at high redshift from ground-based studies. The difference in [O$_{\rm \,III}$] emission between these DSFGs and other high-redshift galaxies reflects their more evolved stellar populations (> 10 Myr), larger dust reservoirs (M$_{\rm dust}$ $\sim$ 10$^{9 - 11}$ M$_{\odot}$), metal-rich interstellar medium ($Z \sim 0.5 - 2$ Z$_{\odot}$), and likely weaker ionization radiation fields. Ancillary [C$_{\rm \,II}$] emission on two targets provide $L_{[{\rm O}_{\rm \,III}]} / L_{[{\rm C}_{\rm \,II}]}$ ratios at 0.3 - 0.9, suggesting that ionized gas represents a smaller fraction of the total gas reservoir in DSFGs, consistent with theoretical models of DSFGs as transitional systems between gas-rich, turbulent disks and more evolved, gas-poor galaxies. Expanding samples of DSFGs with [O$_{\rm \,III}$] emission will be key to place this heterogeneous, poorly-understood galactic phase in its astrophysical context.

astro-ph.GA↗

arXiv2023

FLASH: Faint Lenses from Associated Selection with Herschel

We report the ALMA Band 7 observations of 86 Herschel sources that likely contain gravitationally-lensed galaxies. These sources are selected with relatively faint 500 $μ$m flux densities between 15 to 85 mJy in an effort to characterize the effect of lensing across the entire million-source Herschel catalogue. These lensed candidates were identified by their close proximity to bright galaxies in the near-infrared VISTA Kilo-Degree Infrared Galaxy Survey (VIKING) survey. Our high-resolution observations (0.15 arcsec) confirm 47 per cent of the initial candidates as gravitational lenses, while lensing cannot be excluded across the remaining sample. We find average lensing masses (log M/M$_{\odot}$ = 12.9 $\pm$ 0.5) in line with previous experiments, although direct observations might struggle to identify the most massive foreground lenses across the remaining 53 per cent of the sample, particularly for lenses with larger Einstein radii. Our observations confirm previous indications that more lenses exist at low flux densities than expected from strong galaxy-galaxy lensing models alone, where the excess is likely due to additional contributions of cluster lenses and weak lensing. If we apply our method across the total 660 sqr. deg. H-ATLAS field, it would allow us to robustly identify 3000 gravitational lenses across the 660 square degree Herschel ATLAS fields.

astro-ph.GA↗

arXiv2021

Modelling high-resolution ALMA observations of strongly lensed dustystar forming galaxies detected by Herschel

We present modelling of ~0.1arcsec resolution Atacama Large Millimetre/sub-millimeter Array imaging of seven strong gravitationally lensed galaxies detected by the Herschel Space Observatory. Four of these systems are galaxy-galaxy scale strong lenses, with the remaining three being group-scale lenses. Through careful modelling of visibilities, we infer the mass profiles of the lensing galaxies and by determining the magnification factors, we investigate the intrinsic properties and morphologies of the lensed sub-millimetre sources. We find that these sub-millimetre sources all have ratios of star formation rate to dust mass that is consistent with or in excess of the mean ratio for high-redshift sub-millimetre galaxies and low redshift ultra-luminous infrared galaxies. The contribution to the infrared luminosity from possible AGN is not quantified and so could be biasing our star formation rates to higher values. The majority of our lens models have mass density slopes close to isothermal, but some systems show significant differences.

astro-ph.GA↗

arXiv2017

Exploring cosmic origins with CORE: gravitational lensing of the CMB

Lensing of the CMB is now a well-developed probe of large-scale clustering over a broad range of redshifts. By exploiting the non-Gaussian imprints of lensing in the polarization of the CMB, the CORE mission can produce a clean map of the lensing deflections over nearly the full-sky. The number of high-S/N modes in this map will exceed current CMB lensing maps by a factor of 40, and the measurement will be sample-variance limited on all scales where linear theory is valid. Here, we summarise this mission product and discuss the science that it will enable. For example, the summed mass of neutrinos will be determined to an accuracy of 17 meV combining CORE lensing and CMB two-point information with contemporaneous BAO measurements, three times smaller than the minimum total mass allowed by neutrino oscillations. In the search for B-mode polarization from primordial gravitational waves with CORE, lens-induced B-modes will dominate over instrument noise, limiting constraints on the gravitational wave power spectrum amplitude. With lensing reconstructed by CORE, one can "delens" the observed polarization internally, reducing the lensing B-mode power by 60%. This improves to 70% by combining lensing and CIB measurements from CORE, reducing the error on the gravitational wave amplitude by 2.5 compared to no delensing (in the null hypothesis). Lensing measurements from CORE will allow calibration of the halo masses of the 40000 galaxy clusters that it will find, with constraints dominated by the clean polarization-based estimators. CORE can accurately remove Galactic emission from CMB maps with its 19 frequency channels. We present initial findings that show that residual Galactic foreground contamination will not be a significant source of bias for lensing power spectrum measurements with CORE. [abridged]

astro-ph.CO↗

arXiv2017

Statistics of the fractional polarisation of compact radio sources in Planck maps

In this work we apply the stacking technique to estimate the average fractional polarisation from 30 to 353 GHz of a primary sample of 1560 compact sources - essentially all radio sources - detected in the 30 GHz Planck all-sky map and listed in the second version of the Planck Catalogue of Compact Sources (PCCS2). We divide our primary sample in two subsamples according to whether the sources lay (679 sources) or not (881 sources) inside the sky region defined by the Planck Galactic mask (fsky ~ 60 per cent) and the area around the Magellanic Clouds. We find that the average fractional polarisation of compact sources is approximately constant (with frequency) in both samples (with a weighted mean over all the channels of 3.08 per cent outside and 3.54 per cent inside the Planck mask). In the sky region outside the adopted mask, we also estimate the μ and σ parameters for the log-normal distribution of the fractional polarisation, finding a weighted mean value over all the Planck frequency range of 1.0 for σ and 0.7 for μ (that would imply a weighted mean value for the median fractional polarisation of 1.9 per cent).

astro-ph.GA↗

arXiv2017

Exploring Cosmic Origins with CORE: Inflation

We forecast the scientific capabilities to improve our understanding of cosmic inflation of CORE, a proposed CMB space satellite submitted in response to the ESA fifth call for a medium-size mission opportunity. The CORE satellite will map the CMB anisotropies in temperature and polarization in 19 frequency channels spanning the range 60-600 GHz. CORE will have an aggregate noise sensitivity of $1.7 μ$K$\cdot \,$arcmin and an angular resolution of 5' at 200 GHz. We explore the impact of telescope size and noise sensitivity on the inflation science return by making forecasts for several instrumental configurations. This study assumes that the lower and higher frequency channels suffice to remove foreground contaminations and complements other related studies of component separation and systematic effects, which will be reported in other papers of the series "Exploring Cosmic Origins with CORE." We forecast the capability to determine key inflationary parameters, to lower the detection limit for the tensor-to-scalar ratio down to the $10^{-3}$ level, to chart the landscape of single field slow-roll inflationary models, to constrain the epoch of reheating, thus connecting inflation to the standard radiation-matter dominated Big Bang era, to reconstruct the primordial power spectrum, to constrain the contribution from isocurvature perturbations to the $10^{-3}$ level, to improve constraints on the cosmic string tension to a level below the presumptive GUT scale, and to improve the current measurements of primordial non-Gaussianities down to the $f_{NL}^{\rm local} < 1$ level. For all the models explored, CORE alone will improve significantly on the present constraints on the physics of inflation. Its capabilities will be further enhanced by combining with complementary future cosmological observations.

astro-ph.CO↗

arXiv2017

Exploring Cosmic Origins with CORE: Cosmological Parameters

We forecast the main cosmological parameter constraints achievable with the CORE space mission which is dedicated to mapping the polarisation of the Cosmic Microwave Background (CMB). CORE was recently submitted in response to ESA's fifth call for medium-sized mission proposals (M5). Here we report the results from our pre-submission study of the impact of various instrumental options, in particular the telescope size and sensitivity level, and review the great, transformative potential of the mission as proposed. Specifically, we assess the impact on a broad range of fundamental parameters of our Universe as a function of the expected CMB characteristics, with other papers in the series focusing on controlling astrophysical and instrumental residual systematics. In this paper, we assume that only a few central CORE frequency channels are usable for our purpose, all others being devoted to the cleaning of astrophysical contaminants. On the theoretical side, we assume LCDM as our general framework and quantify the improvement provided by CORE over the current constraints from the Planck 2015 release. We also study the joint sensitivity of CORE and of future Baryon Acoustic Oscillation and Large Scale Structure experiments like DESI and Euclid. Specific constraints on the physics of inflation are presented in another paper of the series. In addition to the six parameters of the base LCDM, which describe the matter content of a spatially flat universe with adiabatic and scalar primordial fluctuations from inflation, we derive the precision achievable on parameters like those describing curvature, neutrino physics, extra light relics, primordial helium abundance, dark matter annihilation, recombination physics, variation of fundamental constants, dark energy, modified gravity, reionization and cosmic birefringence. (ABRIDGED)

astro-ph.CO↗