Examinando por Autor "Kramer, C."

Mostrando 1 - 9 de 9

Acceso Abierto
Calibration and performance of the NIKA2 camera at the IRAM 30-m Telescope.
(EDP Sciences, 2020-05-18) Perotto, L.; Ponthieu, N.; Marcías Pérez, J. F.; Adam, R.; Ade, P.; André, P.; Andrianasolo, A.; Aussel, H.; Beelen, A.; Benoit, A.; Berta, S.; Bideaud, A.; Bourrion, O.; Calvo, M.; Catalano, A.; Comis, B.; De Petris, M.; Désert, F. X.; Doyle, S.; Driessen, E. F. C.; Gómez, A.; Goupy, J.; John, D.; Kéruzoré, F.; Kramer, C.; Ladjelate, B.; Lagache, G.; Leclercq, S.; Lestrade, L. F.; Maury, A.; Mauskopf, P.; Mayet, F.; Monfardini, A.; Navarro, Sara; Peñalver, J.; Pierfederici, F.; Pisano, G.; Revéret, V.; Ritacco, A.; Roussel, H.; Ruppin, F.; Schuster, K.; Shu, S.; Sievers, A.; Tucker, C.; Zylka, R.; Díaz García, Pedro; Romero Guzman, Catalina; Agence Nationale de la Recherche (ANR); European Commission (EC); Ministerio de Economía y Competitividad (MINECO); Centre National D'Etudes Spatiales (CNES); 0000-0001-6937-5052; 0000-0002-3101-0768; 0000-0002-5385-2763; 0000-0001-6478-7883; 0000-0001-9995-4792; 0000-0002-8752-1401; 0000-0001-7859-2139; 0000-0002-6370-2101; 0000-0001-6397-5516; 0000-0002-1371-5705; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Context. NIKA2 is a dual-band millimetre continuum camera of 2 900 kinetic inductance detectors, operating at 150 and 260 GHz, installed at the IRAM 30-m telescope in Spain. Open to the scientific community since October 2017, NIKA2 will provide key observations for the next decade to address a wide range of open questions in astrophysics and cosmology. Aims. Our aim is to present the calibration method and the performance assessment of NIKA2 after one year of observation. Methods. We used a large data set acquired between January 2017 and February 2018 including observations of primary and secondary calibrators and faint sources that span the whole range of observing elevations and atmospheric conditions encountered by the IRAM 30-m telescope. This allowed us to test the stability of the performance parameters against time evolution and observing conditions. We describe a standard calibration method, referred to as the "Baseline" method, to translate raw data into flux density measurements. This includes the determination of the detector positions in the sky, the selection of the detectors, the measurement of the beam pattern, the estimation of the atmospheric opacity, the calibration of absolute flux density scale, the flat fielding, and the photometry. We assessed the robustness of the performance results using the Baseline method against systematic effects by comparing results using alternative methods. Results. We report an instantaneous field of view of 6.5 ' in diameter, filled with an average fraction of 84%, and 90% of valid detectors at 150 and 260 GHz, respectively. The beam pattern is characterised by a FWHM of 17.6 '' +/- 0.1 '' and 11.1 '' +/- 0.2 '', and a main-beam efficiency of 47%+/- 3%, and 64%+/- 3% at 150 and 260 GHz, respectively. The point-source rms calibration uncertainties are about 3% at 150 GHz and 6% at 260 GHz. This demonstrates the accuracy of the methods that we deployed to correct for atmospheric attenuation. The absolute calibration uncertainties are of 5%, and the systematic calibration uncertainties evaluated at the IRAM 30-m reference Winter observing conditions are below 1% in both channels. The noise equivalent flux density at 150 and 260 GHz are of 9 +/- 1 mJy s(1/2) and 30 +/- 3 mJy s(1/2). This state-of-the-art performance confers NIKA2 with mapping speeds of 1388 +/- 174 and 111 +/- 11 arcmin(2) mJy(-2) h(-1) at 150 and 260 GHz. Conclusions. With these unique capabilities of fast dual-band mapping at high (better that 18 '') angular resolution, NIKA2 is providing an unprecedented view of the millimetre Universe.
Acceso Abierto
Evolutionary view through the starless cores in Taurus Deuteration in TMC 1-C and TMC 1-CP
(EDP Sciences, 2021-06-15) Navarro Almaida, D.; Fuente, A.; Majumdar, L.; Wakelam, V.; Caselli, P.; Rivière Marichalar, P.; Treviño Morales, S. P.; Cazaux, S.; Jiménez Serra, I.; Kramer, C.; Chacón Tanarro, A.; Kirk, J. M.; Ward Thompson, D.; Tafalla, M.; Centre National D'Etudes Spatiales (CNES); Agencia Estatal de Investigación (AEI); European Research Council (ERC); Navarro Almaida, D. [0000-0002-8499-7447]; Fuente, A. [0000-0001-6317-6343]; Wakelam, V. [0000-0001-9676-2605]; Caselli, P. [0000-0003-1481-7911]; Rivière Marichalar, P. [0000-0003-0969-8137]; Treviño Morales, S. P. [0000-0002-4033-2881]; Ward Thompson, D. [0000-0003-1140-2761]; Jiménez Serra, I. [0000-0003-4493-8714]; Tafalla, M. [0000-0002-2569-1253]
Context. The chemical and physical evolution of starless and pre-stellar cores are of paramount importance to understanding the process of star formation. The Taurus Molecular Cloud cores TMC 1-C and TMC 1-CP share similar initial conditions and provide an excellent opportunity to understand the evolution of the pre-stellar core phase. Aims. We investigated the evolutionary stage of starless cores based on observations towards the prototypical dark cores TMC 1-C and TMC 1-CP. Methods. We mapped the prototypical dark cores TMC 1-C and TMC 1-CP in the CS 3 → 2, C34S 3 → 2, 13CS 2 → 1, DCN 1 → 0, DCN 2 → 1, DNC 1 → 0, DNC 2 → 1, DN13C 1 → 0, DN13C 2 → 1, N2H+ 1 → 0, and N2D+ 1 → 0 transitions. We performed a multi-transitional study of CS and its isotopologs, DCN, and DNC lines to characterize the physical and chemical properties of these cores. We studied their chemistry using the state-of-the-art gas-grain chemical code NAUTILUS and pseudo time-dependent models to determine their evolutionary stage. Results. The central nH volume density, the N2H+ column density, and the abundances of deuterated species are higher in TMC 1-C than in TMC 1-CP, yielding a higher N2H+ deuterium fraction in TMC 1-C, thus indicating a later evolutionary stage for TMC 1-C. The chemical modeling with pseudo time-dependent models and their radiative transfer are in agreement with this statement, allowing us to estimate a collapse timescale of ~1 Myr for TMC 1-C. Models with a younger collapse scenario or a collapse slowed down by a magnetic support are found to more closely reproduce the observations towards TMC 1-CP. Conclusions. Observational diagnostics seem to indicate that TMC 1-C is in a later evolutionary stage than TMC 1-CP, with a chemical age ~1 Myr. TMC 1-C shows signs of being an evolved core at the onset of star formation, while TMC 1-CP appears to be in an earlier evolutionary stage due to a more recent formation or, alternatively, a collapse slowed down by a magnetic support.
Acceso Abierto
Exploiting NIKA2/XMM-Newton imaging synergy for intermediate-mass high-z galaxy clusters within the NIKA2 SZ large program
(EDP Sciences, 2020-12-04) Kéruzoré, F.; Mayet, F.; Pratt, G. W.; Adam, R.; Ade, P.; André, P.; Andrianasolo, A.; Arnaud, M.; Aussel, H.; Bartalucci, I.; Beelen, A.; Benoit, A.; Berta, S.; Bourrion, O.; Calvo, M.; Catalano, A.; De Petris, M.; Désert, F. X.; Doyle, S.; Driessen, E. F. C.; Gómez, A.; Goupy, J.; Kramer, C.; Ladjelate, B.; Lagache, G.; Leclercq, S.; Lestrade, L. F.; Marcías Pérez, J. F.; Mauskopf, P.; Monfardini, A.; Perotto, L.; Pisano, G.; Pointecouteau, E.; Ponthieu, N.; Revéret, V.; Ritacco, A.; Roussel, H.; Ruppin, F.; Schuster, K.; Shu, S.; Sievers, A.; Tucker, C.; Romero Guzman, Catalina; Agence Nationale de la Recherche (ANR); European Commission (EC); National Aeronautics and Space Administration (NASA); Kéruzoré, F. h[0000-0002-9605-5588]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
High-resolution mapping of the intracluster medium (ICM) up to high redshift and down to low masses is crucial to derive accurate mass estimates of the galaxy cluster and to understand the systematic effects affecting cosmological studies based on galaxy clusters. We present a spatially resolved Sunyaev-Zel'dovich (SZ)/X-ray analysis of ACT-CL J0215.4+0030, a high-redshift (z=0.865) galaxy cluster of intermediate mass (M-500 similar or equal to 3.5x10(14) M-circle dot) observed as part of the ongoing NIKA2 SZ large program, which is a follow-up of a representative sample of objects at 0.5 <= z <= 0.9. In addition to the faintness and small angular size induced by its mass and redshift, the cluster is contaminated by point sources that significantly affect the SZ signal. This is therefore an interesting case study for the most challenging sources of the NIKA2 cluster sample. We present the NIKA2 observations of this cluster and the resulting data. We identified the point sources that affect the NIKA2 maps of the cluster as submillimeter galaxies with counterparts in catalogs of sources constructed by the SPIRE instrument on board the Herschel observatory. We reconstructed the ICM pressure profile by performing a joint analysis of the SZ signal and of the point-source component in the NIKA2 150 GHz map. This cluster is a very weak source that lies below the selection limit of the Planck catalog. Nonetheless, we obtained high-quality estimates of the ICM thermodynamical properties with NIKA2. We compared the pressure profile extracted from the NIKA2 map to the pressure profile obtained from X-ray data alone by deprojecting the public XMM-Newton observations of the cluster. We combined the NIKA2 pressure profile with the X-ray deprojected density to extract detailed information on the ICM. The radial distribution of its thermodynamic properties (the pressure, temperature and entropy) indicate that the cluster has a highly disturbed core. We also computed the hydrostatic mass of the cluster, which is compatible with estimations from SZ and X-ray scaling relations. We conclude that the NIKA2 SZ large program can deliver quality information on the thermodynamics of the ICM even for one of its faintest clusters after a careful treatment of the contamination by point sources.
Acceso Abierto
Gas phase Elemental abundances in Molecular cloudS (GEMS) II. On the quest for the sulphur reservoir in molecular clouds: the H2S case
(EDP Sciences, 2020-05-12) Navarro Almaida, D.; Le Gal, R.; Fuente, A.; Rivière Marichalar, P.; Wakelam, V.; Cazaux, S.; Caselli, P.; Laas, J. C.; Alonso Albi, T.; Loison, J. C.; Gerin, M.; Kramer, C.; Roueff, E.; Bachiller, R.; Commerçon, B.; Friesen, R.; García Burillo, S.; Goicoechea, J. R.; Giuliano, B. M.; Jiménez Serra, I.; Kirk, J. M.; Lattanzi, V.; Malinen, J.; Marcelino, N.; Martín Doménech, R.; Muñoz Caro, G. M.; Pineda, J.; Tercero, B.; Treviño Morales, S. P.; Roncero, O.; Tafalla, M.; Ward Thompson, D.; European Research Council (ERC); European Commission (EC); Agencia Estatal de Investigación (AEI); Navarro Almaida, D. [0000-0002-8499-7447]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Context. Sulphur is one of the most abundant elements in the Universe. Surprisingly, sulphuretted molecules are not as abundant as expected in the interstellar medium and the identity of the main sulphur reservoir is still an open question. Aims. Our goal is to investigate the H2S chemistry in dark clouds, as this stable molecule is a potential sulphur reservoir. Methods. Using millimeter observations of CS, SO, H2S, and their isotopologues, we determine the physical conditions and H2S abundances along the cores TMC 1-C, TMC 1-CP, and Barnard 1b. The gas-grain model NAUTILUS is used to model the sulphur chemistry and explore the impact of photo-desorption and chemical desorption on the H2S abundance. Results. Our modeling shows that chemical desorption is the main source of gas-phase H2S in dark cores. The measured H2S abundance can only be fitted if we assume that the chemical desorption rate decreases by more than a factor of 10 when nH > 2 × 104. This change in the desorption rate is consistent with the formation of thick H2O and CO ice mantles on grain surfaces. The observed SO and H2S abundances are in good agreement with our predictions adopting an undepleted value of the sulphur abundance. However, the CS abundance is overestimated by a factor of 5-10. Along the three cores, atomic S is predicted to be the main sulphur reservoir. Conclusions. The gaseous H2S abundance is well reproduced, assuming undepleted sulphur abundance and chemical desorption as the main source of H2S. The behavior of the observed H2S abundance suggests a changing desorption efficiency, which would probe the snowline in these cold cores. Our model, however, highly overestimates the observed gas-phase CS abundance. Given the uncertainty in the sulphur chemistry, we can only conclude that our data are consistent with a cosmic elemental S abundance with an uncertainty of a factor of 10.
Acceso Abierto
Gas phase Elemental abundances in Molecular cloudS (GEMS) III. Unlocking the CS chemistry: the CS+O reaction
(EDP Sciences, 2021-02-02) Bulut, N.; Roncero, O.; Aguado, A.; Loison, J. C.; Navarro Almaida, D.; Wakelam, V.; Fuente, A.; Roueff, E.; Le Gal, R.; Caselli, P.; Gerin, M.; Hickson, K. M.; Spezzano, S.; Riviére Marichalar, P.; Alonso Albi, T.; Bachiller, R.; Jiménez Serra, I.; Kramer, C.; Tercero, B.; Rodríguez Baras, M.; García Burillo, S.; Goicoechea, J. R.; Treviño Morales, S. P.; Esplugues, G.; Cazaux, S.; Commercon, B.; Laas, J. C.; Kirk, J.; Lattanzi, V.; Martín Doménech, R.; Muñoz Caro, G. M.; Pineda, J. E.; Ward Thompson, D.; Tafalla, M.; Marcelino, N.; Malinen, J.; Friesen, R.; Giuliano, B. M.; Agúndez, Marcelino; Hacar, A.; Agencia Estatal de Investigación (AEI); Marcelino, N. [0000-0001-7236-4047]; Roncero, O. [0000-0002-8871-4846]; Pineda, J. [0000-0002-3972-1978]; Agundez, M. [0000-0003-3248-3564]; Tafalla, M. [0000-0002-2569-1253]
Context. Carbon monosulphide (CS) is among the most abundant gas-phase S-bearing molecules in cold dark molecular clouds. It is easily observable with several transitions in the millimeter wavelength range, and has been widely used as a tracer of the gas density in the interstellar medium in our Galaxy and external galaxies. However, chemical models fail to account for the observed CS abundances when assuming the cosmic value for the elemental abundance of sulfur. Aims. The CS+O → CO + S reaction has been proposed as a relevant CS destruction mechanism at low temperatures, and could explain the discrepancy between models and observations. Its reaction rate has been experimentally measured at temperatures of 150−400 K, but the extrapolation to lower temperatures is doubtful. Our goal is to calculate the CS+O reaction rate at temperatures <150 K which are prevailing in the interstellar medium. Methods. We performed ab initio calculations to obtain the three lowest potential energy surfaces (PES) of the CS+O system. These PESs are used to study the reaction dynamics, using several methods (classical, quantum, and semiclassical) to eventually calculate the CS + O thermal reaction rates. In order to check the accuracy of our calculations, we compare the results of our theoretical calculations for T ~ 150−400 K with those obtained in the laboratory. Results. Our detailed theoretical study on the CS+O reaction, which is in agreement with the experimental data obtained at 150–400 K, demonstrates the reliability of our approach. After a careful analysis at lower temperatures, we find that the rate constant at 10 K is negligible, below 10−15 cm3 s−1, which is consistent with the extrapolation of experimental data using the Arrhenius expression. Conclusions. We use the updated chemical network to model the sulfur chemistry in Taurus Molecular Cloud 1 (TMC 1) based on molecular abundances determined from Gas phase Elemental abundances in Molecular CloudS (GEMS) project observations. In our model, we take into account the expected decrease of the cosmic ray ionization rate, ζH2, along the cloud. The abundance of CS is still overestimated when assuming the cosmic value for the sulfur abundance.
Acceso Abierto
GASTON: Galactic Star Formation with NIKA2 – evidence for the mass growth of star-forming clumps
(Oxford Academics: Oxford University Press, 2021-01-25) Rigby, A. J.; Peretto, N.; Adam, R.; Ade, P.; Anderson, M.; André, P.; Andrianasolo, A.; Aussel, H.; Bacmann, A.; Beelen, A.; Benoit, A.; Berta, S.; Bourrion, O.; Bracco, A.; Calvo, M.; Catalano, A.; De Petris, M.; Désert, F. X.; Doyle, S.; Driessen, E. F. C.; Gómez, A.; Goupy, J.; Kéruzoré, F.; Kramer, C.; Ladjelate, B.; Lagache, G.; Leclercq, S.; Lestrade, L. F.; Marcías Pérez, J. F.; Mauskopf, P.; Mayet, F.; Monfardini, A.; Perotto, L.; Pisano, G.; Ponthieu, N.; Revéret, V.; Ristorcelli, I.; Ritacco, A.; Roussel, H.; Ruppin, F.; Schuster, K.; Shu, S.; Sievers, A.; Tucker, C.; Watkins, E. J.; Díaz García, Pedro; Romero Guzman, Catalina; Science and Technology Facilities Council (STFC); National Aeronautics and Space Administration (NASA); European Research Council (ERC); European Commission (EC); Ritacco, A. [0000-0003-0162-8206]; Rigby, A. J. [0000-0002-3351-2200]; Peretto, N. [0000-0002-6893-602X]; Bacmann, A. [0000-0003-1263-4986]
Determining the mechanism by which high-mass stars are formed is essential for our understanding of the energy budget and chemical evolution of galaxies. By using the New IRAM KIDs Array 2 (NIKA2) camera on the Institut de Radio Astronomie Millimétrique (IRAM) 30-m telescope, we have conducted high-sensitivity and large-scale mapping of a fraction of the Galactic plane (GP) in order to search for signatures of the transition between the high- and low-mass star-forming modes. Here, we present the first results from the Galactic Star Formation with NIKA2 (GASTON) project, a Large Programme at the IRAM 30-m telescope that is mapping ≈2 deg2 of the inner GP, centred on ℓ = 23∘.9, b = 0∘.05, as well as targets in Taurus and Ophiuchus in 1.15- and 2.00-mm continuum wavebands. In this paper, we present the first of the GASTON GP data taken, and present initial science results. We conduct an extraction of structures from the 1.15-mm maps using a dendrogram analysis and, by comparison to the compact source catalogues from Herschel survey data, we identify a population of 321 previously undetected clumps. Approximately 80 per cent of these new clumps are 70-μm-quiet, and may be considered as starless candidates. We find that this new population of clumps are less massive and cooler, on average, than clumps that have already been identified. Further, by classifying the full sample of clumps based upon their infrared-bright fraction – an indicator of evolutionary stage – we find evidence for clump mass growth, supporting models of clump-fed high-mass star formation.
Acceso Abierto
The multi-phase ISM in the nearby composite AGN-SB galaxy NGC 4945: large-scale (parsecs) mechanical heating
(EDP Sciences, 2020-10-15) Bellocchi, E.; Martín Pintado, J.; Güsten, R.; Requeña Torres, M. A.; Harris, A.; Van der Werf, P. P.; Israel, F. P.; Weiss, A.; Kramer, C.; García Burillo, S.; Stutzki, J.; European Space Agency (ESA); Agencia Estatal de Investigación (AEI); Comunidad de Madrid; Bellocchi, E. [0000-0001-9791-4228]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Context. Understanding the dominant heating mechanism in the nuclei of galaxies is crucial to understanding star formation in starbursts (SBs), active galactic nuclei (AGN) phenomena, and the relationship between star formation and AGN activity in galaxies. Analysis of the carbon monoxide (12CO) rotational ladder versus the infrared continuum emission (hereafter, 12CO/IR) in galaxies with different types of activity reveals important differences between them. Aims. We aim to carry out a comprehensive study of the nearby composite AGN-SB galaxy, NGC 4945, using spectroscopic and photometric data from the Herschel satellite. In particular, we want to characterize the thermal structure in this galaxy using a multi-transition analysis of the spatial distribution of the 12CO emission at different spatial scales. We also want to establish the dominant heating mechanism at work in the inner region of this object at smaller spatial scales (≲200 pc). Methods. We present far-infrared (FIR) and sub-millimeter (sub-mm) 12CO line maps and single spectra (from Jup = 3 to 20) using the Heterodyne Instrument for the Far Infrared (HIFI), the Photoconductor Array Camera and Spectrometer (PACS), and the Spectral and Photometric Imaging REceiver (SPIRE) onboard Herschel, and the Atacama Pathfinder EXperiment (APEX). We combined the 12CO/IR flux ratios and the local thermodynamic equilibrium (LTE) analysis of the 12CO images to derive the thermal structure of the interstellar medium (ISM) for spatial scales raging from ≲200 pc to 2 kpc. In addition, we also present single spectra of low- (12CO, 13CO and [CI]) and high-density (HCN, HNC, HCO+, CS and CH) molecular gas tracers obtained with APEX and HIFI applying LTE and non-LTE (NLTE) analyses. Furthermore, the spectral energy distribution of the continuum emission from the FIR to sub-mm wavelengths is also presented. Results. From the NLTE analysis of the low- and high-density tracers, we derive gas volume densities (103–106 cm−3) for NGC 4945 that are similar to those found in other galaxies with different types of activity. From the 12CO analysis we find a clear trend in the distribution of the derived temperatures and the 12CO/IR ratios. It is remarkable that at intermediate scales (360 pc–1 kpc, or 19″–57″) we see large temperatures in the direction of the X-ray outflow while at smaller scales (≲200 pc–360 pc, or ∼9″–19″), the highest temperature, derived from the high-J lines, is not found toward the nucleus but toward the galaxy plane. The thermal structure derived from the 12CO multi-transition analysis suggests that mechanical heating, like shocks or turbulence, dominates the heating of the ISM in the nucleus of NGC4945 located beyond 100 pc (≳5″) from the center of the galaxy. This result is further supported by published models, which are able to reproduce the emission observed at high-J (PACS) 12CO transitions when mechanical heating mechanisms are included. Shocks and/or turbulence are likely produced by the barred potential and the outflow observed in X–rays.
Acceso Abierto
The XXL Survey XLIV. Sunyaev-Zel’dovich mapping of a low-mass cluster at z ∼ 1: a multi-wavelength approach
(EDP Sciences, 2020-10-13) Ricci, C.; Adam, R.; Eckert, Dominique; Ade, P.; André, P.; Andrianasolo, A.; Altieri, B.; Aussel, H.; Beelen, A.; Benoist, C.; Benoit, A.; Berta, S.; Bideaud, A.; Birkinshaw, M.; Bourrion, O.; Boutigny, D.; Bremer, M.; Calvo, M.; Cappi, A.; Chiappetti, L.; Catalano, A.; De Petris, M.; Désert, F. X.; Doyle, S.; Driessen, E. F. C.; Faccioli, L.; Ferrari, C.; Fotopoulou, S.; Gastaldello, F.; Giles, P.; Gómez, A.; Goupy, J.; Hahn, O.; Horellou, C.; Kéruzoré, F.; Koulouridis, E.; Kramer, C.; Ladjelate, B.; Lagache, G.; Leclercq, S.; Lestrade, J. F.; Marcías Pérez, J. F.; Maughan, B.; Maurogordato, S.; Mauskopf, P.; Monfardini, A.; Pacaud, F.; Perotto, L.; Pierre, M.; Pisano, G.; Pompei, E.; Ponthieu, N.; Revéret, V.; Ritacco, A.; Roussel, H.; Ruppin, F.; Sánchez Portal, M.; Schuster, K.; Sereno, M.; Shu, S.; Slievers, A.; Tucker, C.; Umetsu, K.; Romero Guzman, Catalina; European Research Council (ERC); Agenzia Spaziale Italiana (ASI); European Commission (EC); Umetsu, K. [0000-0002-7196-4822]; Koulouridis, E. [0000-0002-9423-3723]; Altieri, B. [0000-0003-3936-0284]; Giles, P. [0000-0003-4937-8453]; Ricci, M. [0000-0002-3645-9652]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
High-mass clusters at low redshifts have been intensively studied at various wavelengths. However, while more distant objects at lower masses constitute the bulk population of future surveys, their physical state remain poorly explored to date. In this paper, we present resolved observations of the Sunyaev-Zel’dovich (SZ) effect, obtained with the NIKA2 camera, towards the cluster of galaxies XLSSC 102, a relatively low-mass system (M500 ∼ 2 × 1014 M⊙) at z = 0.97 detected from the XXL survey. We combine NIKA2 SZ data, XMM-Newton X-ray data, and Megacam optical data to explore, respectively, the spatial distribution of the gas electron pressure, the gas density, and the galaxies themselves. We find significant offsets between the X-ray peak, the SZ peak, the brightest cluster galaxy, and the peak of galaxy density. Additionally, the galaxy distribution and the gas present elongated morphologies. This is interpreted as the sign of a recent major merging event, which induced a local boost of the gas pressure towards the north of XLSSC 102 and stripped the gas out of the galaxy group. The NIKA2 data are also combined with XXL data to construct the thermodynamic profiles of XLSSC 102, obtaining relatively tight constraints up to about ∼r500, and revealing properties that are typical of disturbed systems. We also explore the impact of the cluster centre definition and the implication of local pressure substructure on the recovered profiles. Finally, we derive the global properties of XLSSC 102 and compare them to those of high-mass-and-low-redshift systems, finding no strong evidence for non-standard evolution. We also use scaling relations to obtain alternative mass estimates from our profiles. The variation between these different mass estimates reflects the difficulty to accurately measure the mass of low-mass clusters at z ∼ 1, especially with low signal-to-noise ratio data and for a disturbed system. However, it also highlights the strength of resolved SZ observations alone and in combination with survey-like X-ray data. This is promising for the study of high redshift clusters from the combination of eROSITA and high resolution SZ instruments and will complement the new generation of optical surveys from facilities such as LSST and Euclid.
Acceso Abierto
Unveiling the Merger Dynamics of the Most Massive MaDCoWS Cluster at z = 1.2 from a Multiwavelength Mapping of Its Intracluster Medium Properties
(The Institute of Physics (IOP), 2020-04-16) Ruppin, F.; McDonald, M.; Brodwin, M.; Adam, R.; Ade, P.; André, P.; Adrianasolo, A.; Arnaud, M.; Aussel, H.; Bartalucci, I.; Bautz, M. W.; Beelen, A.; Benoit, A.; Bideaud, A.; Bourrion, O.; Calvo, M.; Catalano, A.; Comis, B.; Decker, B.; De Petris, M.; Désert, F. X.; Doyle, S.; Driessen, E. F. C.; Eisenhardt, P. R. M.; Gómez, A.; González, A. H.; Goupy, J.; Kéruzoré, F.; Kramer, C.; Ladjelate, B.; Lagache, G.; Leclercq, S.; Lestrade, L. F.; Marcías Pérez, J. F.; Mauskopf, P.; Mayet, F.; Monfardini, A.; Moravec, E.; Perotto, L.; Pisano, G.; Pointecouteau, E.; Ponthieu, N.; Pratt, G. W.; Revéret, V.; Ritacco, A.; Roussel, H.; Schuster, K.; Shu, S.; Sievers, A.; Stanford, S. A.; Stern, D.; Tucker, C.; Zylka, R.; Romero Guzman, Catalina; Agence Nationale de la Recherche (ANR); European Commission (EC); National Aeronautics & Space Administration (NASA); Ministerio de Economía y Competitividad (MINECO); Brodwin, M. [0000-0002-4208-798X]; Ade, P. [0000-0002-5127-0401]; González, A. H. [0000-0002-0933-8601]; Moravec, E. [0000-0001-9793-5416]; Romero, C. [0000-0001-5725-0359]; Stern, D. [0000-0003-2686-9241]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The characterization of the Intracluster Medium (ICM) properties of high-redshift galaxy clusters is fundamental to our understanding of large-scale structure formation processes. We present the results of a multiwavelength analysis of the very massive cluster MOO J1142+1527 at a redshift z = 1.2 discovered as part of the Massive and Distant Clusters of WISE Survey. This analysis is based on high angular resolution Chandra X-ray and NIKA2 Sunyaev–Zel'dovich (SZ) data. The cluster thermodynamic radial profiles have been obtained with unprecedented precision at this redshift and up to 0.7R500, thanks to the combination of high-resolution X-ray and SZ data. The comparison between the galaxy distribution mapped in infrared by Spitzer and the morphological properties of the ICM derived from the combined analysis of the Chandra and NIKA2 data leads us to the conclusion that the cluster is an ongoing merger. We have estimated a systematic uncertainty on the cluster total mass that characterizes both the impact of the observed deviations from spherical symmetry and of the core dynamics on the mass profile. We further combine the X-ray and SZ data at the pixel level to obtain maps of the temperature and entropy distributions. We find a relatively low-entropy core at the position of the X-ray peak and high-temperature regions located on its south and west sides. This work demonstrates that the addition of spatially resolved SZ observations to low signal-to-noise X-ray data brings a high information gain on the characterization of the evolution of ICM thermodynamic properties at z > 1.