Mariela Martínez Paredes

• PhD in Astrophysics
• Science Teacher at Pinellas County Schools

We investigate the capabilities of the mid-infrared instrument (MIRI) of James Webb Space Telescope (JWST) to advance our knowledge of AGN dust using the spectral fitting technique on an AGN collection of 21 nearby (z < 0.05) AGN (7 type-1 and 14 type-2) observations obtained with the medium resolution spectroscopy (MRS) mode. This collection inclu...

We investigate the capabilities of the mid-infrared instrument (MIRI) of James Webb Space Telescope (JWST) to advance our knowledge of AGN dust using the spectral fitting technique on an AGN collection of 21 nearby (z<0.05) AGN (7 type-1 and 14 type-2) observations obtained with the medium resolution spectroscopy (MRS) mode. This collection include...

Combining the Cloudy photoionization code with updated stellar population synthesis results, we simultaneously model the MIR $\rm {[Ne\,{\small iii}]}/\rm{[Ne\,{\small ii}]}$ vs. $\rm{[O\,{\small iv}]}/\rm{[Ne\,{\small iii}]}$, the MIR-FIR $\rm{[Ne\,{\small iii}]}/\rm{[Ne\,{\small ii}]}$ vs. $\rm{[O\,{\small iv}]}/\rm{[O\,{\small iii}]}$ and the cl...

Combining the {\sc Cloudy} photoionization code with updated stellar population synthesis results, we simultaneously model the MIR $\neiii/\neii$ vs. $\oiv/\neiii$, the MIR-FIR $\neiii/\neii$ vs. $\oiv/\oiii$ and the classical BPT diagnostic diagrams. We focus on the properties of optically classified \hii\,galaxies that lie in the normal star form...

Mrk 477 is the closest type-2 quasar, at a distance of 163 Mpc. This makes it an ideal laboratory for studying the interplay between nuclear activity and star formation with a great level of detail and signal-to-noise. In this Letter we present new mid-infrared (mid-IR) imaging and spectroscopic data with an angular resolution of 0.4″ (∼300 pc) obt...

Mrk 477 is the closest type-2 quasar (QSO2), at a distance of 163 Mpc. This makes it an ideal laboratory for studying the interplay between nuclear activity and star formation with a great level of detail and signal-to-noise. In this Letter we present new mid-infrared (mid-IR) imaging and spectroscopic data with an angular resolution of 0.4 arcsec...

We present a statistical analysis of the properties of the obscuring material around active galactic nuclei (AGN). This study represents the first of its kind for an ultra-hard X-ray (14–195 keV; Swift /BAT), volume-limited ( D L < 40 Mpc) sample of 24 Seyfert (Sy) galaxies (BCS 40 sample) using high angular resolution infrared data and various tor...

We present a statistical analysis of the properties of the obscuring material around active galactic nuclei (AGN). This study represents the first of its kind for an ultra-hard X-ray (14-195keV; Swift/BAT) volume-limited (DL<40 Mpc) sample of 24 Seyfert (Sy) galaxies (BCS40 sample) using high angular resolution infrared data and various torus model...

Using published work on the narrow-line region of Active Galactic Nuclei, a comparison is carried out among the [OIII] λ4363Å/5007Å ratios (ROIII) observed in quasars, Seyfert 2's and the spatially resolved ENLR plasma. Using the weak [ArIV] λ4711Å/λ4740Å doublet observed by Koski (1978) among Seyfert 2's, we find evidence of a Narrow-Line Region (...

Thanks to ground-based infrared and submillimeter observations the study of the dusty torus of nearby active galactic nuclei has greatly advanced in the last years. With the aim of further investigating the nuclear mid-infrared emission of the archetypal Seyfert 2 galaxy NGC 1068, here we present a fitting to the N - and Q -band Michelle/Gemini spe...

Thanks to ground-based infrared and sub-mm observations the study of the dusty torus of nearby AGN has greatly advanced in the last years. With the aim of further investigating the nuclear mid-infrared emission of the archetypal Seyfert 2 galaxy NGC1068, here we present a fitting to the N- and Q-band Michelle/Gemini spectra. We initially test sever...

Using published work on the Narrow Line Region of Active Nuclei, we make a comparison of the observed [O III] 4363A/5007A ratio observed among quasars, Seyfert 2's and spatially resolved NLR plasma. It is broadly accepted that the span of this ratio among quasars, from 0.015 to 0.2, is the result of collisional deexcitation as corroborated by Baski...

To study the nuclear (≲1 kpc) dust of nearby ( z < 0.1) quasi-stellar objects (QSOs), we obtained new near-infrared (NIR) high angular resolution (∼0.″3) photometry in the H and Ks bands for 13 QSOs with available mid-infrared (MIR) high angular resolution spectroscopy (∼7.5–13.5 μ m). We find that in most QSOs, the NIR emission is unresolved. We s...

We study the nuclear ( ≲1kpc) dust of nearby ( z<0.1) type 1 Quasi Stellar Objects (QSOs). We used new near-infrared (NIR) high angular resolution ( ∼0.3arcsec) photometry in the H and Ks bands, for 13 QSOs with available mid-infrared (MIR) high angular resolution spectroscopy ( ∼7.5−13.5μm). The new NIR data were obtained from the cameras CIRCE an...

To study the nuclear ($\lesssim1\,$kpc) dust of nearby ($z<0.1$) type 1 Quasi Stellar Objects (QSOs) we obtained new near-infrared (NIR) high angular resolution ($\sim0.3$ arcsec) photometry in the H and Ks bands, for 13 QSOs with available mid-infrared (MIR) high angular resolution spectroscopy ($\sim7.5-13.5\,\mu$m). We find that in most QSOs the...

As part of the Early Science Large Millimeter Telescope projects, we report the detection of nine double-peaked molecular lines, produced by a rotating molecular torus, in the ultraluminous infrared galaxies (ULIRG) – Compton-thick active galactic nuclei (AGN) galaxy UGC 5101. The double-peaked lines we report correspond to molecular transitions of...

We measure the 10 and 18 μ m silicate features in a sample of 67 local ( z < 0.1) type 1 active galactic nuclei (AGN) with available Spitzer spectra dominated by nonstellar processes. We find that the 10 μ m silicate feature peaks at with a strength (Si p = ln f p (spectrum)/f p (continuum)) of , while the 18 μ m one peaks at with a strength of . W...

We measure the 10 and $18\mu$m silicate features in a sample of 67 local ($z<0.1$) type 1 active galactic nuclei (AGN) with available {\it Spitzer} spectra dominated by non-stellar processes. We find that the $10\mu$m silicate feature peaks at $10.3^{+0.7}_{-0.9}\mu$m with a strength (Si$_{p}$ = ln f$_{p}$(spectrum)/f$_{p}$(continuum)) of $0.11^{+0...

In order to understand the diversity of classes observed in active galactic nuclei (AGNs), a geometrically and optically thick torus of gas and dust is required to obscure the central engine depending on the line of sight to the observer. We perform a simultaneous fitting of X-ray and mid-infrared (mid-IR) spectra to investigate whether the same st...

In order to understand the diversity of classes observed in active galactic nuclei (AGN), a geometrically and optically thick torus of gas and dust is required to obscure the central engine depending on the line of sight to the observer. We perform a simultaneous fitting of X-ray and mid-infrared (mid-IR) spectra to investigate if the same structur...

This is the second in a series of papers devoted to exploring a set of six dusty models of active galactic nuclei (AGN) with available spectral energy distributions. These models are the smooth torus by Fritz et al., the clumpy torus by Nenkova et al., the clumpy torus by Hönig & Kishimoto, the two-phase torus by Siebenmorgen et al., the two-phase...

At distances from the active galaxy nucleus where the ambient temperature falls below ∼1500–1800 K, dust is able to survive. It is thus possible to have a large dusty structure present that surrounds the active galaxy nucleus. This is the first of two papers aiming at comparing six dusty torus models with available spectral energy distributions, na...

At distances from the active galaxy nucleus (AGN) where the ambient temperature falls below ~1500-1800 K, dust is able to survive. It is thus possible to have a large dusty structure present which surrounds the AGN. This is the first of two papers aiming at comparing six dusty torus models with available SEDs, namely Fritz et al. (2006), Nenkova et...

This is the second in a series of papers devoted to explore a set of six dusty models of active galactic nuclei (AGN) with available spectral energy distributions (SEDs). These models are the smooth torus by Fritz et al. (2006), the clumpy torus by Nenkova et al. (2008B), the clumpy torus by Hoenig & Kishimoto (2010), the two phase torus by Siebenm...

We investigated how the most common dusty torus models reproduce both the 10 and 18μm silicate emission features observed in the nuclear infrared (IR) Spitzer spectrum of type 1 active galactic nuclei (AGN). We use a sample of type 1 AGN for which the Spitzer spectrum is mostly dominated by the emission of the AGN (>80%), and the 10μm silicate emis...

Dust close (∼few pc) to the accretion disk in active galactic nuclei (AGNs) is key to understanding many of their observational signatures, and it is key to tracing how the AGN is fed or even evolves along its duty cycle. With estimated sizes of less than 10 pc, as constrained by mid-IR (MIR) high angular resolution data, only the superb spatial re...

We examine star formation activity in a distant (z < 0.1) and flux-limited sample of quasars (QSOs). Midinfrared (MIR) spectral diagnostics at high spatial resolution (∼0.4 arcsec) yield star formation rates (SFRs) in the inner regions (∼300 pc-1 kpc) for 13 of 20 of the sample members. We group these objects according to the size probed by the hig...

Dust close (∼few pc) to the accretion disk in active galactic nuclei (AGN) is key to understand many of their observational signatures and it is key to trace how the AGN is fed or even evolve along its duty cycle. With estimated sizes of less than 10 pc, as constrained by mid-infrared high angular resolution data, only the superb spatial resolution...

Accepted in ApJ

We study the detectability of the emission associated with the AGN dusty structure at sub-mm wavelengths using ALMA, in a theoretical and observational way. Theoretically, we use the Clumpy models from Nenkova et al. together with the mid-infrared to X-ray and the radio fundamental plane scaling relations. We find that it is more likely to detect b...

We examine star formation activity in a distance- (z<0.1) and flux-limited sample of quasars (QSOs). Mid-infrared (MIR) spectral diagnostics at high spatial resolution (~0.4 arcsec) yield star formation rates (SFRs) in the inner regions (~300 pc to 1 kpc) for 13 of 20 of the sample members. We group these objects according to the size probed by the...

We combine new (NGC 1275, NGC 4151, and NGC 5506) and previously published (Cygnus A, Mrk 231, and NGC 1068) sub-arcsecond resolutionmid-infrared (MIR; 8-13 μm) imagingand spectro-polarimetric observations of six Seyfert galaxies using CanariCam on the 10.4-m Gran Telescopio CANARIAS. These observations reveal a diverse set of physical processes re...

We combine new (NGC 1275, NGC 4151, and NGC 5506) and previously published (Cygnus A, Mrk 231, and NGC 1068) sub-arcsecond resolution mid-infrared (MIR; 8-13 $\mu$m) imaging- and spectro-polarimetric observations of six Seyfert galaxies using CanariCam on the 10.4-m Gran Telescopio CANARIAS. These observations reveal a diverse set of physical proce...

We studied the circumnuclear MIR emission in a sample of 19 local active galactic nuclei (AGN) with high spatial resolution spectra using T-ReCS (Gemini) and CanariCam (GTC), together with IRS/Spitzer observations. We measured the flux and the equivalent width for the 11.3 micron PAH feature and the [SIV] line emission as a function of galactocentr...

We studied the circumnuclear MIR emission in a sample of 19 local active galactic nuclei (AGN) with high spatial resolution spectra using T-ReCS (Gemini) and CanariCam (GTC), together with IRS/Spitzer observations. We measured the flux and the equivalent width for the 11.3 micron PAH feature and the [SIV] line emission as a function of galactocentr...

Several authors have claimed that less luminous active galactic nuclei (AGNs) are not capable of sustaining a dusty torus structure. Thus, a gradual resizing of the torus is expected when the AGN luminosity decreases. Our aim is to examine mid-infrared observations of local AGNs of different luminosities for the gradual resizing and disappearance o...

Several authors have claimed that the less luminous active galactic nuclei (AGN) are not capable of sustaining the dusty torus structure. Thus, a gradual re-sizing of the torus is expected when the AGN luminosity decreases. Our aim is to confront mid-infrared observations of local AGN of different luminosities with this scenario. We decomposed abou...

A talk on the recent results obtained from analyse the nuclear (~few parsec) mid-infrared emission in a sample of nearby (z<0.1) quasars.

We present mid-infrared (MIR, 7.5-13.5 $\mu$m) imaging and spectroscopy observations obtained with the CanariCam (CC) instrument on the 10.4m Gran Telescopio CANARIAS for a sample of 20 nearby, MIR bright and X-ray luminous QSOs. We find that for the majority of QSOs the MIR emission is unresolved at angular scales nearly 0.3 arcsec, corresponding...

We present mid-infrared (MIR, 7.5-13.5 $\mu$m) imaging and spectroscopy observations obtained with the CanariCam (CC) instrument on the 10.4m Gran Telescopio CANARIAS for a sample of 20 nearby, MIR bright and X-ray luminous QSOs. We find that for the majority of QSOs the MIR emission is unresolved at angular scales nearly 0.3 arcsec, corresponding...

We present high-angular (0.17$-$0.35 arcsec) resolution imaging polarimetric observations of Mrk 231 in the 3.1 $\mu$m filter using MMT-Pol on the 6.5-m MMT, and in the 8.7 $\mu$m, 10.3 $\mu$m, and 11.6 $\mu$m filters using CanariCam on the 10.4-m Gran Telescopio CANARIAS. In combination with already published observations, we compile the 1$-$12 $\...

We present high-angular (0.17$-$0.35 arcsec) resolution imaging polarimetric observations of Mrk 231 in the 3.1 $\mu$m filter using MMT-Pol on the 6.5-m MMT, and in the 8.7 $\mu$m, 10.3 $\mu$m, and 11.6 $\mu$m filters using CanariCam on the 10.4-m Gran Telescopio CANARIAS. In combination with already published observations, we compile the 1$-$12 $\...

We investigate the evolutionary connection between local IR-bright galaxies ($\log L_{\rm IR}\ge 11.4\,L_\odot$) and quasars. We use high angular resolution ($\sim$ 0.3-0.4 arcsec $\sim$ few hundred parsecs) $8-13\,\mu$m ground-based spectroscopy to disentangle the AGN mid-IR properties from those of star formation. The comparison between the nucle...

We investigate the evolutionary connection between local IR-bright galaxies ($\log L_{\rm IR}\ge 11.4\,L_\odot$) and quasars. We use high angular resolution ($\sim$ 0.3-0.4 arcsec $\sim$ few hundred parsecs) $8-13\,\mu$m ground-based spectroscopy to disentangle the AGN mid-IR properties from those of star formation. The comparison between the nucle...

We present 31.5 micron imaging photometry of 11 nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We tentatively detect extended 31 micron emission for the first time in our sample. In combination with this new data set, subarc...

We present 31.5 micron imaging photometry of 11 nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We tentatively detect extended 31 micron emission for the first time in our sample. In combination with this new data set, subarc...

We present an analysis of the nuclear infrared (IR, 1.6–18 μm) emission of the ultraluminous IR galaxy UGC 5101 to derive the properties of its active galactic nucleus (AGN) and its obscuring material. We use new mid-IR high angular resolution (0.3–0.5 arcsec) imaging using the Si-2 filter (λC = 8.7 μm) and 7.5–13 μm spectroscopy taken with CanariC...

We have carried out extensive and detailed photoionization modeling to successfully constrain the locations of different emission-line galaxies in optical and mid-infrared diagnostic diagrams. Our model grids cover a wide range in parameter space for the active galaxy continuum and starburst galaxies with different stellar population laws and metal...

We present nuclear spectral energy distributions (SEDs) from 1 to 18 micron of a small sample of nearby, nearly face-on and undisturbed Seyfert galaxies without prominent nuclear dust lanes. These nuclear SEDs probe the central ~35 pc of the galaxies, on average, and include photometric and spectroscopic infrared (IR) data. We use these SEDs, the c...

We present MIR sub-arcsec observations of Mrk 1383, a nearby QSO, part of a sample of nearby QSOs currently being observed with the 10.4 m Gran Telescopio de Canarias (GTC). The radial profile of the QSO is analyzed and we find that most of the MIR emission is unresolved (\theta ~ 0.4", 600 pc) and consistent with previous measurements from Spitzer...

We present MIR sub-arcsec observations of Mrk 1383, a nearby QSO, part of a sample of nearby QSOs currently being observed with the 10.4 m Gran Telescopio de Canarias (GTC). The radial profile of the QSO is analyzed and we find that most of the MIR emission is unresolved (θ ∼ 0.4 " , 600 pc) and consistent with previous measurements from Spitzer (θ...

Active galactic nuclei (AGN) are thought to harbor massive black holes (M_BH &ap; 10^6-10^8 M_&sun; surrounded by an accretion disk responsible for the enormous energy rates observed in their unresolved nuclei. Seyfert galaxies represent the most common type of AGN. Seyfert 1 galaxies have broad permitted (FWHM &ap; 1-5×10^3 km s^{-1} and narrow (F...

RESUMEN En el presente trabajo hemos estudiado la relación entre las líneas de emisión de alta y baja ionización del [O IV] 25,89 µm (54,93 eV), [Ne III] 15,56 µm (40,96 eV), y [Ne II] 12,81 µm (21,6 eV) con el propósito de restringir la contribución del núcleo activo de galaxias (Active Galactic Nuclei, AGN) y la formación estelar en una muestra d...

We continue a systematic study of chemical abundances of the strontium filament found in the ejecta of η Carinae. To this end we interpret the emission spectrum of Sc ii and Cr ii using multilevel non-local thermodynamic equilibrium models. Since the atomic data for these ions were previously unavailable, we carry out ab initio calculations of radi...