Examinando por Autor "Labiano, Alvaro"

Mostrando 1 - 9 de 9

Acceso Abierto
A radio-jet driven outflow in the Seyfert 2 galaxy NGC 2110?
(EDP Sciences, 2023-05-10) Peralta de Arriba, L.; Alonso Herrero, A.; García Burillo, S.; García Bernete, I.; Villar Martín, M.; García Lorenzo, B.; Davies, R. I.; Rosario, D.; Hönig, S. F.; Levenson, N. A.; Packham, C.; Ramos Almeida, C.; Pereira Santaella, M.; Audibert, A.; Bellocchi, E.; Hicks, E. K. S.; Labiano, Alvaro; Ricci, C.; Rigopoulou, D.; European Commission (EC); Gobierno de Canarias; University of Oxford; Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT); Ministerio de Ciencia e Innovación (MICINN); Science and Technology Facilities Council (STFC); Centros de Excelencia Severo Ochoa, CENTRO NACIONAL DE BIOTECNOLOGIA (CNB), SEV-2017-0712
We present a spatially-resolved study of the ionised gas in the central 2 kpc of the Seyfert 2 galaxy NGC 2110 and investigate the role of its moderate luminosity radio jet (kinetic radio power of $P_\mathrm{jet} = 2.3 \times 10^{43}\mathrm{erg\ s^{-1}}$). We use new optical integral-field observations taken with the MEGARA spectrograph at GTC. We fit the emission lines with a maximum of two Gaussian components, except at the AGN position where we used three. Aided by existing stellar kinematics, we use the observed velocity and velocity dispersion of the emission lines to classify the different kinematic components. The disc component is characterised by lines with $\sigma \sim 60-200\ \mathrm{km\ s^{-1}}$. The outflow component has typical values of $\sigma \sim 700\ \mathrm{km\ s^{-1}}$ and is confined to the central 400 pc, which is coincident with linear part of the radio jet detected in NGC 2110. At the AGN position, the [O III]$\lambda$5007 line shows high velocity components reaching at least $1000\ \mathrm{km\ s^{-1}}$. This and the high velocity dispersions indicate the presence of outflowing gas outside the galaxy plane. Spatially-resolved diagnostic diagrams reveal mostly LI(N)ER-like excitation in the outflow and some regions in the disc, which could be due to the presence of shocks. However, there is also Seyfert-like excitation beyond the bending of the radio jet, probably tracing the edge of the ionisation cone that intercepts with the disc of the galaxy. NGC 2110 follows well the observational trends between the outflow properties and the jet radio power found for a few nearby Seyfert galaxies. All these pieces of information suggest that part of observed ionised outflow in NGC 2110 might be driven by the radio jet. However, the radio jet was bent at radial distances of 200 pc (in projection) from the AGN, and beyond there, most of the gas in the galaxy disc is rotating.
Restringido
Calibration strategy for the SPICA/SAFARI instrument
(SPIE Digital Library, 2020-12-13) Shipman, R. F.; Vandenbussche, B.; Castillo Domínguez, E.; Labiano, Alvaro; Jellema, W.; Orlando, A.; Comunidad de Madrid; Angiola, O. [0000-0001-9464-3100]; info:eu-repo/semantics/restrictedAccess
SPICA is a mid to far infra-red space mission to explore the processes that form galaxies, stars and planets. SPICA/SAFARI is the far infrared spectrometer that provides near-background limited observations between 34 and 230 micrometers. The core of SAFARI consists of 4 grating modules, dispersing light onto 5 arrays of TES detectors per module. The grating modules provide low resolution (250) instantaneous spectra over the entire wavelength range. The high resolution (1500 to 12000) mode is accomplished by placing a Fourier Transform Spectrometer (FTS) in front of the gratings. Each grating module detector sees an interferogram from which the high resolution spectrum can be constructed. SAFARI data will be a convolution of complex spectral, temporal and spatial information. Along with spectral calibration accuracy of < 1 %, a relative flux calibration of 1% and an absolute flux calibration accuracy of 10% are required. This paper will discuss the calibration strategy and its impact on the instrument design of SAFARI
Restringido
Extinction in the 11.2 mu m PAH band and the low L-11.2/L-IR in ULIRGs
(Oxford Academics: Blackwell Publishing, 2020-08-05) Hernández Caballero, A.; Spoon, H. W. W.; Alonso Herrero, A.; Hatziminaoglou, Evanthia; Magdis, Georgios E.; Pérez González, Pablo G.; Pereira Santaella, M.; Arribas, S.; Cortzen, I.; Labiano, Alvaro; Piqueras López, J.; Rigopoulou, D.; National Aeronautics and Space Administration (NASA); Agencia Estatal de Investigación (AEI); Villum Fonden; Danish National Research Foundation (DNRF); Comunidad de Madrid; 0000-0002-4872-2294; 0000-0001-9197-7623; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We present a method for recovering the intrinsic (extinction-corrected) luminosity of the 11.2 mu m PAH band in galaxy spectra. Using 105 high S/N Spitzer/IRS spectra of star-forming galaxies, we show that the equivalent width ratio of the 12.7 and 11.2 mu m PAH bands is independent on the optical depth (tau), with small dispersion (similar to 5 percent) indicative of a nearly constant intrinsic flux ratio R-int = (f(12.7)/f(11.2))(int) = 0.377 +/- 0.020. Conversely, the observed flux ratio, R-obs = (f(12.7)/f(11.2))(obs), strongly correlates with the silicate strength (S-sil) confirming that differences in R-obs reflect variation in tau. The relation between R-obs and S-sil reproduces predictions for the Galactic Centre extinction law but disagrees with other laws. We calibrate the total extinction affecting the 11.2 mu m PAH from R-obs, which we apply to another sample of 215 galaxies with accurate measurements of the total infrared luminosity (L-IR) to investigate the impact of extinction on L-11.2/L-IR. Correlation between L-11.2/L-IR and R-obs independently on L-IR suggests that increased extinction explains the well-known decrease in the average L-11.2/L-IR at high L-IR. The extinction-corrected L-11.2 is proportional to L-IR in the range L-IR = 10(9)-10(13) L-circle dot. These results consolidate L-11.2 as a robust tracer of star formation in galaxies.
Restringido
Mid-IR cosmological spectrophotometric surveys from space: Measuring AGN and star formation at the cosmic noon with a SPICA-like mission
(Cambridge University Press, 2021-04-23) Spignoglio, L.; Mordini, S.; Fernández Ontiveros, J. A.; Alonso Herrero, A.; Armus, L.; Bisigello, L.; Calura, F.; Carrera, F. J.; Cooray, A.; Dannerbauer, H.; Decarli, R.; Egami, E.; Elbaz, D.; Franceschini, A.; González Alfonso, E.; Graziani, L.; Gruppioni, C.; Hatziminaoglou, Evanthia; Kaneda, H.; Kohno, K.; Labiano, Alvaro; Magdis, Georgios E.; Malkan, M. A.; Matsuhara, H.; Nagao, T.; Naylor, D.; Pereira Santaella, M.; Pozzi, F.; Rodighiero, G.; Roelfsema, Peter; Serjeant, S.; Vignali, C.; Wang, L.; Yamada, T.; Agenzia Spaziale Italiana (ASI); Agencia Estatal de Investigación (AEI); Comunidad de Madrid; Spignoglio, L. [0000-0001-8840-1551]; Fernández Ontiveros, J. A. [0000-0001-9490-899X]; Gruppioni, C. [0000-0002-5836-4056]; Graziani, L. [0000-0002-9231-1505]; Unidad de Excelencia Científica María de Maeztu Instituto de Astrofísica de Cantabria, MDM-2017-0765; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We use the SPace Infrared telescope for Cosmology and Astrophysics (SPICA) project as a template to demonstrate how deep spectrophotometric surveys covering large cosmological volumes over extended fields (1– ) with a mid-IR imaging spectrometer (17– ) in conjunction with deep photometry with a far-IR camera, at wavelengths which are not affected by dust extinction can answer the most crucial questions in current galaxy evolution studies. A SPICA-like mission will be able for the first time to provide an unobscured three-dimensional (3D, i.e. x, y, and redshift z) view of galaxy evolution back to an age of the universe of less than 2 Gyrs, in the mid-IR rest frame. This survey strategy will produce a full census of the Star Formation Rate (SFR) in the universe, using polycyclic aromatic hydrocarbons (PAH) bands and fine-structure ionic lines, reaching the characteristic knee of the galaxy luminosity function, where the bulk of the population is distributed, at any redshift up to . Deep follow-up pointed spectroscopic observations with grating spectrometers onboard the satellite, across the full IR spectral range (17– ), would simultaneously measure Black Hole Accretion Rate (BHAR), from high-ionisation fine-structure lines, and SFR, from PAH and low- to mid-ionisation lines in thousands of galaxies from solar to low metallicities, down to the knee of their luminosity functions. The analysis of the resulting atlas of IR spectra will reveal the physical processes at play in evolving galaxies across cosmic time, especially its heavily dust-embedded phase during the activity peak at the cosmic noon ( –3), through IR emission lines and features that are insensitive to the dust obscuration.
Acceso Abierto
Multiphase feedback processes in the Sy2 galaxy NGC 5643
(EDP Sciences, 2021-01-12) García Bernete, I.; Alonso Herrero, A.; García Burillo, S.; Pereira Santaella, M.; García Lorenzo, B.; Carrera, F. J.; Rigopoulou, D.; Ramos Almeida, C.; Villar Martín, M.; González Martín, O.; Hicks, E. K. S.; Labiano, Alvaro; Ricci, C.; Mateos, S.; Ministerio de Economía y Competitividad (MINECO); Science and Technology Facilities Council (STFC); Agencia Estatal de Investigación (AEI); Comunidad de Madrid; Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT); García Lorenzo, M. B. [0000-0002-7228-7173]; Ramos Almeida, C. [0000-0001-8353-649X]; Carrero, F. J. [0000-0003-2135-9023]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737; Unidad de Excelencia Científica María de Maeztu AGENCIA ESTATAL CONSEJO SUPERIOR DE INVESTIGACIONES CIENTIFICAS (CSIC), MDM-2017-0765
We study the multiphase feedback processes in the central ∼3 kpc of the barred Seyfert 2 galaxy NGC 5643. We used observations of the cold molecular gas (ALMA CO(2−1) transition) and ionized gas (MUSE IFU optical emission lines). We studied different regions along the outflow zone, which extends out to ∼2.3 kpc in the same direction (east-west) as the radio jet, as well as nuclear and circumnuclear regions in the host galaxy disk. The CO(2−1) line profiles of regions in the outflow and spiral arms show two or more different velocity components: one associated with the host galaxy rotation, and the others with out- or inflowing material. In the outflow region, the [O III]λ5007 Å emission lines have two or more components: the narrow component traces rotation of the gas in the disk, and the others are related to the ionized outflow. The deprojected outflowing velocities of the cold molecular gas (median Vcentral ∼ 189 km s−1) are generally lower than those of the outflowing ionized gas, which reach deprojected velocities of up to 750 km s−1 close to the active galactic nucleus (AGN), and their spatial profiles follow those of the ionized phase. This suggests that the outflowing molecular gas in the galaxy disk is being entrained by the AGN wind. We derive molecular and ionized outflow masses of ∼5.2 × 107 M⊙ (αCOGalactic) and 8.5 × 104 M⊙ and molecular and ionized outflow mass rates of ∼51 M⊙ yr−1 (αCOGalactic) and 0.14 M⊙ yr−1, respectively. This means that the molecular phase dominates the outflow mass and outflow mass rate, while the kinetic power and momentum of the outflow are similar in both phases. However, the wind momentum loads (Ṗout/ṖAGN) for the molecular and ionized outflow phases are ∼27−5 (αCOGalactic and αCOULIRGs) and < 1, which suggests that the molecular phase is not momentum conserving, but the ionized phase most certainly is. The molecular gas content (Meast ∼ 1.5 × 107 M⊙; αCOGalactic) of the eastern spiral arm is approximately 50−70% of the content of the western one. We interpret this as destruction or clearing of the molecular gas produced by the AGN wind impacting in the eastern side of the host galaxy (negative feedback process). The increase in molecular phase momentum implies that part of the kinetic energy from the AGN wind is transmitted to the molecular outflow. This suggests that in Seyfert-like AGN such as NGC 5643, the radiative or quasar and the kinetic or radio AGN feedback modes coexist and may shape the host galaxies even at kiloparsec scales through both positive and (mild) negative feedback.
Acceso Abierto
PDRs4All VIII: Mid-IR emission line inventory of the Orion Bar
(EDP Sciences, 2024-04-04) Van De Putte, Dries; Meshaka, Raphael; Trahin, Boris; Habart, Emilie; Peeters, Els; Berné, Olivier; Alarcón, Felipe; Canin, Amélie; Chown, Ryan; Schroetter, Llane; Sidhu, Ameek; Boersma, Christiaan; Bron, Emeric; Dartois, Emmanuel; Goicoechea, Javier R.; Gordon, Karl D.; Onaka, Takashi; Tielens, Alexander G. G. M.; Verstraete, Laurent; Wolfire, Mark G.; Abergel, Alain; Bergin, Edwin A.; Bernard-Salas, Jeronimo; Cami, Jan; Cuadrado, Sara; Dicken, Daniel; Elyajouri, Meriem; Fuente, Asuncion; Joblin, Christine; Baria, Khan; Lacinbala, Ozan; Languignon, David; Le Gal, Romane; Maragkoudakis, Alexandros; Okada, Yoko; Pasquini, Sofia; Pound, Marc W.; Robberto, Massimo; Röllig, Markus; Schefter, Bethany; Schirmer, Thiébaut; Tabone, Benoit; Vicente, Sílvia; Zannese, Marion; Colgan, Sean W. J.; He, Jinhua; Rouillé, Gaël; Togi, Aditya; Aleman, Isabel; Auchettl, Rebecca; Baratta, Giuseppe Antonio; Bejaoui, Salma; Bera, Partha P.; Black, John H.; Boulanger, Francois; Bouwman, Jordy; Brandl, Bernhard; Brechignac, Philippe; Brünken, Sandra; Buragohain, Mridusmita; Burkhardt, Andrew; Candian, Alessandra; Cazaux, Stéphanie; Cernicharo, J.; Chabot, Marin; Chakraborty, Shubhadip; Champion, Jason; Cooke, Ilsa R.; Coutens, Audrey; Cox, Nick L. J.; Demyk, Karine; Donovan Meyer, Jennifer; Foschino, Sacha; García-Lario, Pedro; Gerin, Maryvonne; Gottlieb, Carl A.; Guillard, Pierre; Gusdorf, Antoine; Hartigan, Patrick; Herbst, Eric; Hornekaer, Liv; Issa, Lina; Jäger, Cornelia; Janot-Pacheco, Eduardo; Kannavou, Olga; Kaufman, Michael; Kemper, Francisca ; Kendrew, Sarah; Kirsanova, Maria S. ; Klaassen, Pamela; Kwok, Sun; Labiano, Alvaro; Lai, Thomas S.-Y.; Le Floch, Bertrand; Le Petit, Franck; Li, Aigen; Linz, Hendrik; Mackie, Cameron J.; Madden, Suzanne C.; Mascetti, Joëlle; McGuire, Brett A.; Merino, Pablo; Micelotta, Elisabetta R.; MorseJon A. ,; Mulas, Giacomo; Neelamkodan, Naslim; Ohsawa, Ryou; Omont, Alain; Paladini, Roberta; Palumbo, Maria Elisabetta; Pathak, Amit; Pendleton, Yvonne J.; Petrignani, Annemieke; Pino, Thomas; Puga, Elena; Rangwala, Naseem; Rapacioli, Mathias; Rho, Jeonghee; Ricca, Alessandra; Roman-Duval, Julia; Roser, Joseph; Roueff, Evelyne; Salama, Farid; Sales, Dinalva A.; Sandstrom, Karin; Sarre, Peter; Sciamma-O’Brien, Ella; Sellgren, Kris; Shenoy, Sachindev S.; Teyssier, David; Thomas, Richard D.; Witt, Adolf N.; Wootten, Alwyn; Ysard, Nathalie; Zettergren, Henning; Zhang, Yong; Zhang, Ziwei E.; Zhen, Junfeng; Chinese Academy of Sciences (CAS); Space Telescope Science Institute (STScI); Science and Engineering Research Board (SERB); Ministerio de Ciencia e Innovación (MICINN); Japan Society for the Promotion of Science (JSPS); European Commission (EC); Deutsche Forschungsgemeinschaft (DFG); Ames Research Center, NASA (ARC); Banaras Hindu University (BHU)
Context. Mid-infrared emission features are important probes of the properties of ionized gas and hot or warm molecular gas, which are difficult to probe at other wavelengths. The Orion Bar photodissociation region (PDR) is a bright, nearby, and frequently studied target containing large amounts of gas under these conditions. Under the “PDRs4All” Early Release Science Program for JWST, a part of the Orion Bar was observed with MIRI integral field unit (IFU) spectroscopy, and these high-sensitivity IR spectroscopic images of very high angular resolution (0.2″) provide a rich observational inventory of the mid-infrared (MIR) emission lines, while resolving the H II region, the ionization front, and multiple dissociation fronts. Aims. We list, identify, and measure the most prominent gas emission lines in the Orion Bar using the new MIRI IFU data. An initial analysis summarizes the physical conditions of the gas and demonstrates the potential of these new data and future IFU observations with JWST. Methods. The MIRI IFU mosaic spatially resolves the substructure of the PDR, its footprint cutting perpendicularly across the ionization front and three dissociation fronts. We performed an up-to-date data reduction, and extracted five spectra that represent the ionized, atomic, and molecular gas layers. We identified the observed lines through a comparison with theoretical line lists derived from atomic data and simulated PDR models. The identified species and transitions are summarized in the main table of this work, with measurements of the line intensities and central wavelengths. Results. We identified around 100 lines and report an additional 18 lines that remain unidentified. The majority consists of H I recombination lines arising from the ionized gas layer bordering the PDR. The H I line ratios are well matched by emissivity coefficients from H recombination theory, but deviate by up to 10% because of contamination by He I lines. We report the observed emission lines of various ionization stages of Ne, P, S, Cl, Ar, Fe, and Ni. We show how the Ne III/Ne II, S IV/S III, and Ar III/Ar II ratios trace the conditions in the ionized layer bordering the PDR, while Fe III/Fe II and Ni III/Ni II exhibit a different behavior, as there are significant contributions to Fe II and Ni II from the neutral PDR gas. We observe the pure-rotational H2 lines in the vibrational ground state from 0–0 S(1) to 0–0 S (8), and in the first vibrationally excited state from 1–1 S (5) to 1–1 S(9). We derive H2 excitation diagrams, and for the three observed dissociation fronts, the rotational excitation can be approximated with one thermal (~700 K) component representative of an average gas temperature, and one nonthermal component (~2700 K) probing the effect of UV pumping. We compare these results to an existing model of the Orion Bar PDR, and find that the predicted excitation matches the data qualitatively, while adjustments to the parameters of the PDR model are required to reproduce the intensity of the 0–0 S (6) to S (8) lines.
Acceso Abierto
Physics of ULIRGs with MUSE and ALMA: The PUMA project II. Are local ULIRGs powered by AGN? The subkiloparsec view of the 220 GHz continuum
(EDP Sciences, 2021-07-12) Pereira Santaella, M.; Colina, L.; García Burillo, S.; Lamperti, I.; González Alfonso, E.; Perna, M.; Arribas, S.; Alonso Herrero, A.; Aalto, S.; Combes, F.; Labiano, Alvaro; Piqueras López, J.; Rigopoulou, D.; Van der Werf, P. P.; Comunidad de Madrid; Agencia Estatal de Investigación (AEI); Science and Technology Facilities Council (STFC); Pereira Santaella, M. [0000-0002-4005-9619]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We analyze new high-resolution (400 pc) ∼220 GHz continuum and CO(2–1) Atacama Large Millimeter Array (ALMA) observations of a representative sample of 23 local (z < 0.165) ultra-luminous infrared systems (ULIRGs; 34 individual nuclei) as part of the “Physics of ULIRGs with MUSE and ALMA” (PUMA) project. The deconvolved half-light radii of the ∼220 GHz continuum sources, rcont, are between < 60 pc and 350 pc (median 80–100 pc). We associate these regions with the regions emitting the bulk of the infrared luminosity (LIR). The good agreement, within a factor of 2, between the observed ∼220 GHz fluxes and the extrapolation of the infrared gray-body as well as the small contributions from synchrotron and free–free emission support this assumption. The cold molecular gas emission sizes, rCO, are between 60 and 700 pc and are similar in advanced mergers and early interacting systems. On average, rCO are ∼2.5 times larger than rcont. Using these measurements, we derived the nuclear LIR and cold molecular gas surface densities (ΣLIR = 1011.5 − 1014.3 L⊙ kpc−2 and ΣH2 = 102.9 − 104.2 M⊙ pc−2, respectively). Assuming that the LIR is produced by star formation, the median ΣLIR corresponds to ΣSFR = 2500 M⊙ yr−1 kpc−2. This ΣSFR implies extremely short depletion times, ΣH2/ΣSFR < 1–15 Myr, and unphysical star formation efficiencies > 1 for 70% of the sample. Therefore, this favors the presence of an obscured active galactic nucleus (AGN) in these objects that could dominate the LIR. We also classify the ULIRG nuclei in two groups: (a) compact nuclei (rcont < 120 pc) with high mid-infrared excess emission (ΔL6−20 μm/LIR) found in optically classified AGN; and (b) nuclei following a relation with decreasing ΔL6−20 μm/LIR for decreasing rcont. The majority, 60%, of the nuclei in interacting systems lie in the low-rcont end (<120 pc) of this relation, while this is the case for only 30% of the mergers. This suggests that in the early stages of the interaction, the activity occurs in a very compact and dust-obscured region while, in more advanced merger stages, the activity is more extended, unless an optically detected AGN is present. Approximately two-thirds of the nuclei have nuclear radiation pressures above the Eddington limit. This is consistent with the ubiquitous detection of massive outflows in local ULIRGs and supports the importance of the radiation pressure in the outflow launching process.
Acceso Abierto
Searching for molecular gas inflows and outflows in the nuclear regions of five Seyfert galaxies.
(EDP Sciences, 2020-11-13) Domínguez Fernández, A. J.; Alonso Herrero, A.; García Burillo, S.; Davies, R. I.; Usero, A.; Labiano, Alvaro; Levenson, N. A.; Pereira Santaella, M.; Imanishi, M.; Ramos Almeida, C.; Rigopoulou, D.; Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO); Comunidad de Madrid; Science and Technology Facilities Council (STFC); Ramos Almeida, C. [https://orcid.org/0000-0001-8353-649X]; Davies, R. [https://orcid.org/0000-0003-4949-7217]; Alonso Herrero, A. [https://orcid.org/0000-0001-6794-2519]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Active galactic nucleus (AGN) driven outflows are believed to play an important role in regulating the growth of galaxies, mostly via negative feedback. However, their effects on their hosts are far from clear, especially for low- and moderate-luminosity Seyferts. To investigate this issue, we obtained cold molecular gas observations, traced by the CO(2-1) transition, using the NOEMA interferometer of five nearby (distances between 19 and 58 Mpc) Seyfert galaxies. The resolution of ∼0.3–0.8 (∼30–100 pc) and field of view of NOEMA allowed us to study the CO(2-1) morphology and kinematics in the nuclear regions (∼100 pc) and up to radial distances of ∼900 pc. We detected CO(2-1) emission in all five galaxies with disky or circumnuclear ring-like morphologies. We derived cold molecular gas masses on nuclear (∼100 pc) and circumnuclear (∼650 pc) scales in the range from 106 to 107 M⊙ and from 107 to 108 M⊙, respectively. In all of our galaxies, the bulk of this gas is rotating in the plane of the galaxy. However, noncircular motions are also present. In NGC 4253, NGC 4388, and NGC 7465, we can ascribe the streaming motions to the presence of a large-scale bar. In Mrk 1066 and NGC 4388, the noncircular motions in the nuclear regions are explained as outflowing material due to the interaction of the AGN wind with molecular gas in the galaxy disk. We conclude that for an unambiguous and precise interpretation of the kinematics of the cold molecular gas, we need detailed knowledge of the host galaxy (i.e., presence of bars, interactions, etc.), and also of the ionized gas kinematics and ionization cone geometry.
Acceso Abierto
The nature of point source fringes in mid-infrared spectra acquired with the James Webb Space Telescope
(EDP Sciences, 2020-09-23) Argyriou, I.; Wells, M.; Glasse, A.; Lee, D.; Royer, P.; Vandenbussche, B.; Malamuth, E.; Glauser, A.; Kavanagh, P. J.; Labiano, Alvaro; Lahuis, F.; Mueller, M.; Patapis, P.; Comunidad de Madrid; Argyriou, I. [0000-0003-2820-1077]; Patapis, P. [0000-0001-8718-3732]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Context. As is common for infrared spectrometers, the constructive and destructive interference in different layers of the James Webb Space Telescope (JWST) Mid-Infrared Instrument (MIRI) detector arrays modulate the detected signal as a function of wavelength. The resulting “fringing” in the Medium-Resolution Spectrometer (MRS) spectra varies in amplitude between 10% and 30% of the spectral baseline. A common method for correcting for fringes relies on dividing the data by a fringe flat. In the case of MIRI MRS, the fringe flat is derived from measurements of an extended, spatially homogeneous source acquired during the thermal-vacuum ground verification of the instrument. While this approach reduces fringe amplitudes of extended sources below the percent level, at the detector level, point source fringe residuals vary in a systematic way across the point spread function. The effect could hamper the scientific interpretation of MRS observations of unresolved sources, semi-extended sources, and point sources in crowded fields. Aims. We find MIRI MRS point source fringes to be reproducible under similar observing conditions. We want to investigate whether a generic and accurate correction can be determined. Therefore, we want to identify the variables, if they exist, that would allow for a parametrization of the signal variations induced by point source fringe modulations. Methods. We determine the point source fringe properties by analyzing MRS detector plane images acquired on the ground. We extracted the fringe profile of multiple point source observations and studied the amplitude and phase of the fringes as a function of field position and pixel sampling of the point spread function of the optical chain. Results. A systematic variation in the amplitude and phase of the point source fringes is found over the wavelength range covered by the test sources (4.9 − 5.8 μm). The variation depends on the fraction of the point spread function seen by the detector pixel. We identify the non-uniform pixel illumination as the root cause of the reported systematic variation. This new finding allows us to reconcile the point source and extended source fringe patterns observed in test data during ground verification. We report an improvement after correction of 50% on the 1σ standard deviation of the spectral continuum. A 50% improvement is also reported in line sensitivity for a benchmark test with a spectral continuum of 100 mJy. The improvement in the shape of weak lines is illustrated using a T Tauri model spectrum. Consequently, we verify that fringes of extended sources and potentially semi-extended sources and crowded fields can be simulated by combining multiple point source fringe transmissions. Furthermore, we discuss the applicability of this novel fringe-correction method to the MRS data (and the data of other instruments).