arXiv subjects

John Raymond

Publications and source records attributed to John Raymond.

At least 19 recordsLinked to original sources

arXiv2025

XRISM Spectroscopy of the Stellar-mass Black Hole GRS 1915+105

GRS 1915$+$105 was the stellar-mass black hole that best reproduced key phenomena that are also observed in Type-1 active galactic nuclei. In recent years, however, it has evolved to resemble a Type-2 or Compton-thick AGN. Herein, we report on the first XRISM observation of GRS 1915$+$105. The high-resolution Resolve calorimeter spectrum reveals that a sub-Eddington central engine is covered by a layer of warm, Compton-thick gas. With the obscuration acting as a coronagraph, numerous strong, narrow emission lines from He-like and H-like charge states of Si, S, Ar, Ca, Cr, Mn, Fe, and Ni dominate the spectrum. Radiative recombination continuum (RRC) features are also observed, signaling that much of the emitting gas is photoionized. The line spectrum can be fit by three photoionized emission zones, with broadening and bulk velocities suggestive of an origin in the outer disk atmosphere and/or a slow wind at $r \simeq 10^{6}~GM/c^{2}$. The Fe XXV He-$\alpha$ and Fe XXVI Ly-$\alpha$ lines have a broad base that may indicate some emission from $r \sim 3\times 10^{3}~GM/c^{2}$. These results broadly support a picture wherein the current state in GRS 1915$+$105 is due to obscuration by the irradiated outer disk. This could arise through disk thickening if the Eddington fraction is higher than inferred, but it is more likely due to a warped, precessing disk that has brought the outer disk into the line of sight. We discuss the strengths and weaknesses of this interpretation and our modeling, and possible explanations of some potentially novel spectral features.

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arXiv2025

Dialogue Concerning the Two Shock Codes

In this paper, we summarize the shock physics and the treatment of radiative transfer in two well-established shock codes -- the MAPPINGS code (Dopita1976,Binette1985,Sutherland1993) and the Cox/Raymond code (hereafter CR code) (Cox1972,Raymond1976,Raymond1979). We compare the ionization states, temperatures, electron densities, and the energy transportation of the shock models with shock velocities of 50, 110, 150 and 300 km/s. In summary, both codes adopt the Rankine-Hugoniot flow equation to describe the shock flows, giving the same shock physical properties at the immediate area behind shock fronts. The different treatments of radiative transfer in these two codes leads to somewhat different computation of the ionization and thermal structures of shocks, as well as the emission-line fluxes. This work highlights the importance of the delicate treatment of photoionization in shock models, providing insight of the future development of shock codes, such as the 3D shock codes.

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arXiv2024

Dissecting the Crab Nebula with JWST: Pulsar wind, dusty filaments, and Ni/Fe abundance constraints on the explosion mechanism

We present JWST observations of the Crab Nebula, the iconic remnant of the historical SN 1054. The observations include NIRCam and MIRI imaging mosaics, plus MIRI/MRS IFU spectra that probe two select locations within the ejecta filaments. We derive a high-resolution map of dust emission and show that the grains are concentrated in the innermost, high-density filaments. These dense filaments coincide with multiple synchrotron bays around the periphery of the Crab's pulsar wind nebula (PWN). We measure synchrotron spectral index changes in small-scale features within the PWN's torus region, including the well-known knot and wisp structures. The index variations are consistent with Doppler boosting of emission from particles with a broken power-law distribution, providing the first direct evidence that the curvature in the particle injection spectrum is tied to the acceleration mechanism at the termination shock. We detect multiple nickel and iron lines in the ejecta filaments and use photoionization models to derive nickel-to-iron abundance ratios that are a factor of 3-8 higher than the solar ratio. We also find that the previously reported order-of-magnitude higher Ni/Fe values from optical data are consistent with the lower values from JWST when we reanalyze the optical emission using updated atomic data and account for local extinction from dust. We discuss the implications of our results for understanding the nature of the explosion that produced the Crab Nebula and conclude that the observational properties are most consistent with a low-mass iron-core-collapse supernova, even though an electron-capture explosion cannot be ruled out.

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arXiv2023

Investigating the impact of atomic data uncertainties on measured physical parameters of the Perseus galaxy cluster

Accurate atomic data and plasma models are essential for interpreting the upcoming high-quality spectra from missions like XRISM and Athena. Estimating physical quantities, like temperature, abundance, turbulence, and resonance scattering factor, is highly dependent on the underlying atomic data. We use the AtomDB tool variableapec to estimate the impact of atomic data uncertainties in Einstein A coefficients, collisional rate coefficient, ionization and recombination rates in H-, He- and Li-like iron in modeling the spectrum of Perseus observed by Hitomi. The best-fit temperature, abundance, resonance scattering factor, and turbulence including atomic data uncertainties, varied approximately 17%, 35%, 30%, and 3%, respectively, from the best-fit temperature, abundance, resonance scattering factor, and turbulence estimated without atomic data uncertainties. This indicates that, approximately 32%, 35%, and 25% of the best-fit temperatures, abundances, and resonance scattering factors, including uncertainties lie outside the 3$\sigma$ error regions of their corresponding best-fit values computed with zero atomic data error. Expanding the energy range to 1.8-20.0 keV shows less variability, with 26% of the abundances and 22% of the resonance scattering factors lying outside the 3$\sigma$ error of the best-fit values. We also studied correlations between physical parameters and atomic rate uncertainties to identify key atomic quantities requiring precise lab measurements. We report negative correlations between best-fit temperature and z (1s.2s $^{3}\rm S_{1}\rightarrow 1s^{2}$) collisional rate coefficient, abundance and y (1s.2p $^{3}\rm P_{1}\rightarrow 1s^{2}$) collisional rate coefficient, abundance and z collisional rate coefficient, and positive correlation between resonance scattering factor and w (1s.2p $^{1}\rm P_{1}\rightarrow 1s^{2}$) collisional rate coefficient.

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arXiv2023

New resonance scattering model in AtomDB: application to line suppression in galaxy clusters and elliptical galaxies

In this paper, we present a simple, one-step, self-consistent, and fast resonance scattering model rsapec based on the AtomDB database. This model can be used as an alternative to the commonly used APEC model for fitting such X-ray spectra with optically thick lines. The current model is intended, in general, for verifying the presence of the effect and for spectral modeling of galaxy clusters and elliptical galaxies under applicable assumptions. We test rsapec to derive the line suppression in the elliptical galaxy NGC 4636 and the Perseus cluster of galaxies and obtain resonance suppression of ~ 1.24 and ~ 1.30, respectively.

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arXiv2023

A Nitrogen-rich SNR in M31: SNR Interaction with the CSM at Late Times

We present the discovery of a supernova remnant (SNR) in M31 which is unlike any other remnant known in that galaxy. An optical MMT spectrum of WB92-26 sampling most of this marginally resolved object reveals strong lines of [O II], [Ne III], H I, [O III], [O I], [N II] and [S II], though the H I lines are very weak and the [N II] lines are very strong. Multiple velocity components are visible in those lines, with broad wings extending to $-2000$ and $+1500$ or $2000$ km/s (the heliocentric velocity of M31 is $-300$ km/s). The lines show strong peaks or shoulders near $-750$ km/s, $-50$ km/s, and $+800$ km/s in the M31 frame. The density implied by the [S II] ratio combined with the X-ray luminosity, FUV flux and optical size lead us to conclude that the optical emission lines are generated by shock waves, not photoionization. Consideration of the velocity structure indicates that the emission is from a shock in the circumstellar medium (CSM). This CSM must be depleted in H and enriched in He and N through CNO processing, and it must have had a high velocity before the explosion of the parent star, to explain the broad wings in the emission lines. We estimate the CSM shell to have a mass of 2 Msun, implying a Core Collapse SN. It is likely that Eta Car will produce a remnant resembling WB92-26 a few thousand years after it explodes.

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arXiv2023

The Black Hole Candidate Swift J1728.9$-$3613 and the Supernova Remnant G351.9$-$0.9

A number of neutron stars have been observed within the remnants of the core-collapse supernova explosions that created them. In contrast, black holes are not yet clearly associated with supernova remnants. Indeed, some observations suggest that black holes are ``born in the dark'', i.e. without a supernova explosion. Herein, we present a multi-wavelength analysis of the X-ray transient Swift J1728.9$-$3613, based on observations made with Chandra, ESO-VISTA, MeerKAT, NICER, NuSTAR, Swift, and XMM-Newton. Three independent diagnostics indicate that the system likely harbors a black hole primary. Infrared imaging signals a massive companion star that is broadly consistent with an A or B spectral type. Most importantly, the X-ray binary lies within the central region of the catalogued supernova remnant G351.9$-$0.9. Our deep MeerKAT image at 1.28~GHz signals that the remnant is in the Sedov phase; this fact and the non-detection of the soft X-ray emission expected from such a remnant argue that it lies at a distance that could coincide with the black hole. Utilizing a formal measurement of the distance to Swift J1728.9$-$3613 ($d = 8.4\pm 0.8$ kpc), a lower limit on the distance to G351.9$-$0.9 ($d \geq 7.5$ kpc), and the number and distribution of black holes and supernova remnants within the Milky Way, extensive simulations suggest that the probability of a chance superposition is $<1.7\%$ ($99.7\%$ credible interval). The discovery of a black hole within a supernova remnant would support numerical simulations that produce black holes and remnants, and thus provide clear observational evidence of distinct black hole formation channels. We discuss the robustness of our analysis and some challenges to this interpretation.

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arXiv2022

Line Emission Mapper (LEM): Probing the physics of cosmic ecosystems

The Line Emission Mapper (LEM) is an X-ray Probe for the 2030s that will answer the outstanding questions of the Universe's structure formation. It will also provide transformative new observing capabilities for every area of astrophysics, and to heliophysics and planetary physics as well. LEM's main goal is a comprehensive look at the physics of galaxy formation, including stellar and black-hole feedback and flows of baryonic matter into and out of galaxies. These processes are best studied in X-rays, and emission-line mapping is the pressing need in this area. LEM will use a large microcalorimeter array/IFU, covering a 30x30' field with 10" angular resolution, to map the soft X-ray line emission from objects that constitute galactic ecosystems. These include supernova remnants, star-forming regions, superbubbles, galactic outflows (such as the Fermi/eROSITA bubbles in the Milky Way and their analogs in other galaxies), the Circumgalactic Medium in the Milky Way and other galaxies, and the Intergalactic Medium at the outskirts and beyond the confines of galaxies and clusters. LEM's 1-2 eV spectral resolution in the 0.2-2 keV band will make it possible to disentangle the faintest emission lines in those objects from the bright Milky Way foreground, providing groundbreaking measurements of the physics of these plasmas, from temperatures, densities, chemical composition to gas dynamics. While LEM's main focus is on galaxy formation, it will provide transformative capability for all classes of astrophysical objects, from the Earth's magnetosphere, planets and comets to the interstellar medium and X-ray binaries in nearby galaxies, AGN, and cooling gas in galaxy clusters. In addition to pointed observations, LEM will perform a shallow all-sky survey that will dramatically expand the discovery space.

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arXiv2022

The Circumstellar Environments of Double-Peaked, Calcium-strong Supernovae 2021gno and 2021inl

We present panchromatic observations and modeling of calcium-strong supernovae (SNe) 2021gno in the star-forming host galaxy NGC 4165 (D = 30.5 Mpc) and 2021inl in the outskirts of elliptical galaxy NGC 4923 (D = 80 Mpc), both monitored through the Young Supernova Experiment (YSE) transient survey. The multi-color light curves of both SNe show two peaks, the former peak being derived from shock cooling emission (SCE) and/or shock interaction with circumstellar material (CSM). The primary peak in SN 2021gno is coincident with luminous, rapidly decaying X-ray emission ($L_x = 5 \times 10^{41}$ erg s$^{-1}$) detected by Swift-XRT at $\delta t = 1$ day after explosion, this observation being the second ever detection of X-rays from a calcium-strong transient. We interpret the X-ray emission from SN 2021gno in the context of shock interaction with dense CSM that extends to $r < 3 \times 10^{14}$ cm. Based on modeling of the SN 2021gno X-ray spectrum, we calculate a CSM mass range of $M_{\rm CSM} = (0.3 - 1.6) \times 10^{-3}$ M$_{\odot}$ and particle densities of $n = (1-4) \times 10^{10}$ cm$^{-3}$. Radio non-detections of SN 2021gno indicate a low-density environment at larger radii ($r > 10^{16}$ cm) and a progenitor mass loss rate of $\dot{M} < 10^{-4}$ M$_{\odot}$ yr$^{-1}$, for $v_w = 500$ km s$^{-1}$. For radiation derived from SCE, modeling of the primary light curve peak in both SNe indicates an extended progenitor envelope mass and radius of $M_e = 0.02 - 0.05$ M$_{\odot}$ and $R_e = 30 - 230$ R$_{\odot}$. The explosion properties of SNe 2021gno and 2021inl suggest progenitor systems containing either a low-mass massive star or a white dwarf (WD), the former being unlikely for either object given the lack of star formation at both explosion sites. Furthermore, the progenitor environments of both SNe are consistent with explosion models for low-mass hybrid He/C/O WD + C/O WD binaries.

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arXiv2021

On Synthetic Absorption Line Profiles of Thermally Driven Winds from Active Galactic Nuclei

The warm absorbers observed in more than half of all nearby active galactic nuclei (AGN) are tracers of ionized outflows located at parsec scale distances from the central engine. If the smallest inferred ionization parameters correspond to plasma at a few $10^4$~K, then the gas undergoes a transition from being bound to unbound provided it is further heated to $\sim 10^6$~K at larger radii. Dannen et al. recently discovered that under these circumstances, thermally driven wind solutions are unsteady and even show very dense clumps due to thermal instability. To explore the observational consequences of these new wind solutions, we compute line profiles based on the one-dimensional simulations of Dannen et al. We show how the line profiles from even a simple steady state wind solution depend on the ionization energy (IE) of absorbing ions, which is a reflection of the wind ionization stratification. To organize the diversity of the line shapes, we group them into four categories: weak Gaussians, saturated boxy profiles with and without an extended blue wing, and broad weak profiles. The lines with profiles in the last two categories are produced by ions with the highest IE that probe the fastest regions. Their maximum blueshifts agree with the highest flow velocities in thermally unstable models, both steady state and clumpy versions. In contrast, the maximum blueshifts of the most high IE lines in thermally stable models can be less than half of the actual solution velocities. Clumpy solutions can additionally imprint distinguishable absorption troughs at widely separated velocities.

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arXiv2020

Late-time Observations of Calcium-Rich Transient SN 2019ehk Reveal a Pure Radioactive Decay Power Source

We present $\textit{Hubble Space Telescope}$ imaging of the Calcium-rich supernova (SN) 2019ehk at 276 - 389 days after explosion. These observations represent the latest photometric measurements of a Calcium-rich transient to date and allows for the first opportunity to analyze the late-time evolution of an object in this observational SN class. We find that the late-time bolometric light curve of SN 2019ehk can be described predominantly through the radioactive decay of ${}^{56}\textrm{Co}$ for which we derive a mass of $M({}^{56}\textrm{Co}) = (2.8 \pm 0.1) \times 10^{-2}$$\rm{M}_\odot$. Furthermore, the rate of decline in bolometric luminosity requires the leakage of $\gamma$-rays on timescale $t_{\gamma} = 53.9 \pm 1.30$ days, but we find no statistical evidence for incomplete positron trapping in the SN ejecta. While our observations cannot constrain the exact masses of other radioactive isotopes synthesized in SN 2019ehk, we estimate a mass ratio limit of $M({}^{57}\textrm{Co}) / M({}^{56}\textrm{Co}) \leq 0.030$. This limit is consistent with the explosive nucleosynthesis produced in the merger of low-mass white dwarfs, which is one of the favored progenitor scenarios in early-time studies of SN 2019ehk.

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arXiv2020

SN 2019ehk: A Double-Peaked Ca-rich Transient with Luminous X-ray Emission and Shock-Ionized Spectral Features

We present panchromatic observations and modeling of the Calcium-rich supernova 2019ehk in the star-forming galaxy M100 (d$\approx$16.2 Mpc) starting 10 hours after explosion and continuing for ~300 days. SN 2019ehk shows a double-peaked optical light curve peaking at $t = 3$ and $15$ days. The first peak is coincident with luminous, rapidly decaying $\textit{Swift}$-XRT discovered X-ray emission ($L_x\approx10^{41}~\rm{erg~s^{-1}}$ at 3 days; $L_x \propto t^{-3}$), and a Shane/Kast spectral detection of narrow H$\alpha$ and He II emission lines ($v \approx 500$ km/s) originating from pre-existent circumstellar material. We attribute this phenomenology to radiation from shock interaction with extended, dense material surrounding the progenitor star at $r<10^{15}$ cm and the resulting cooling emission. We calculate a total CSM mass of $\sim$ $7\times10^{-3}$ $\rm{M_{\odot}}$ with particle density $n\approx10^{9}\,\rm{cm^{-3}}$. Radio observations indicate a significantly lower density $n < 10^{4}\,\rm{cm^{-3}}$ at larger radii. The photometric and spectroscopic properties during the second light curve peak are consistent with those of Ca-rich transients (rise-time of $t_r =13.4\pm0.210$ days and a peak B-band magnitude of $M_B =-15.1\pm0.200$ mag). We find that SN 2019ehk synthesized $(3.1\pm0.11)\times10^{-2} ~ \rm{M_{\odot}}$ of ${}^{56}\textrm{Ni}$ and ejected $M_{\rm ej} = (0.72\pm 0.040)~\rm{M_{\odot}}$ total with a kinetic energy $E_{\rm k}=(1.8\pm0.10)\times10^{50}~\rm{erg}$. Finally, deep $\textit{HST}$ pre-explosion imaging at the SN site constrains the parameter space of viable stellar progenitors to massive stars in the lowest mass bin (~10 $\rm{M_{\odot}}$) in binaries that lost most of their He envelope or white dwarfs. The explosion and environment properties of SN 2019ehk further restrict the potential WD progenitor systems to low-mass hybrid HeCO WD + CO WD binaries.

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arXiv2019

Probing Coronal Magnetic Fields with Sungrazing Comets: \hi\ Ly$\alpha$ from Pickup Ions

Observations of sungrazing comets can be used to probe the solar corona, to study the composition of the comets, and to investigate the plasma processes that govern the interaction between the coronal plasma and cometary gas. UVCS observations of the intensities and line profiles of \hi\ Ly$\alpha$ trace the density, temperature and outflow speed of the corona. Analysis of \hi\ Ly$\alpha$ observations of comet C/2002 S2 showed a surprising split in the comet's Ly$\alpha$ tail and an asymmetry of red-shifted and blue-shifted emission across the tail axis. It was suggested that the velocity structure might result from a population of neutrals produced by charge transfer between pickup ions and cometary neutrals. Here we present numerical simulations of the \hi\ Ly$\alpha$ intensity and velocity centroid for sungrazing comets under the assumption that the magnetic field and solar wind are radial. The models qualitatively reproduce the observations of Comet C/2002 S2 and potentially explain the split tail morphology that was seen in C/2002 S2 and also C/2001 C2. They also match the observed red- and blue-shifts, though the solar wind velocity needed to explain the blue-shift implies strong Doppler dimming and requires a higher outgassing rate to match the light curve. However, the models do not match the observations in detail, and we discuss the remaining discrepancies and the uncertainties in the model. We briefly discuss the implications for other UVCS comet observations and sungrazing comet observations with the Metis coronagraph.

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arXiv2019

Ion Charge States in a Time-Dependent Wave-Turbulence-Driven Model of the Solar Wind

Ion fractional charge states, measured in situ in the heliosphere, depend on the properties of the plasma in the inner corona. As the ions travel outward in the solar wind and the electron density drops, the charge states remain essentially unaltered or "frozen in". Thus they can provide a powerful constraint on heating models of the corona and acceleration of the solar wind. We have implemented non-equilibrium ionization calculations into a 1D wave-turbulence-driven (WTD) hydrodynamic solar wind model and compared modeled charge states with the Ulysses 1994-5 in situ measurements. We have found that modeled charge state ratios of $C^{6+}/C^{5+}$ and $O^{7+}/O^{6+}$, among others, were too low compared with Ulysses measurements. However, a heuristic reduction of the plasma flow speed has been able to bring the modeled results in line with observations, though other ideas have been proposed to address this discrepancy. We discuss implications of our results and the prospect of including ion charge state calculations into our 3D MHD model of the inner heliosphere.

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arXiv2018

CHEERS Results from NGC 3393, III: Chandra X-ray Spectroscopy of the Narrow Line Region

We present spatially resolved Chandra narrow-band imaging and imaging spectroscopy of NGC 3393. This galaxy hosts a Compton-thick Seyfert 2 AGN with sub-kpc bipolar outflows that are strongly interacting with the circumnuclear gas. We identify narrow-band excess emission associated with the Ne IX 0.905 keV transition (with likely contributions due to intermediate-state iron emission) that points to strong shocks driven by AGN feedback. Imaging spectroscopy resolves outflow-ISM interaction sites and the surrounding ISM at ~100 pc scales, and suggests the presence of a hot AGN wind above the plane at radii beyond the shock sites. The cross-cone shows evidence for reprocessing of photoionization which has passed through gaps in the torus, and also for collisionally excited plasma which may be powered by a shock-confined equatorial outflow. Deep X-ray observations at sub-arcsecond resolution (such as may be performed very efficiently by Lynx, which would also energetically resolve the complex line emission) are necessary to eliminate model degeneracies and reduce uncertainties in local feedback properties.

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arXiv2018

Predicting the COSIE-C Signal from the Outer Corona up to 3 Solar Radii

We present estimates of the signal to be expected in quiescent solar conditions, as would be obtained with the COronal Spectrographic Imager in the EUV in its coronagraphic mode (COSIE-C). COSIE-C has been proposed to routinely observe the relatively unexplored outer corona, where we know that many fundamental processes affecting both the lower corona and the solar wind are taking place. The COSIE-C spectral band, 186--205 A, is well-known as it has been observed with Hinode EIS. We present Hinode EIS observations that we obtained in 2007 out to 1.5 Rsun, to show that this spectral band in quiescent streamers is dominated by Fe XII and Fe XI and that the ionization temperature is nearly constant. To estimate the COSIE-C signal in the 1.5--3.1 Rsun region we use a model based on CHIANTI atomic data and SoHO UVCS observations in the Si XII and Mg X coronal lines of two quiescent 1996 streamers. We reproduce the observed EUV radiances with a simple density model, photospheric abundances, and a constant temperature of 1.4 MK. We show that other theoretical or semi-empirical models fail to reproduce the observations. We find that the coronal COSIE-C signal at 3 Rsun should be about 5 counts/s per 3.1" pixel in quiescent streamers. This is unprecedented and opens up a significant discovery space. We also briefly discuss stray light and the visibility of other solar features. In particular, we present UVCS observations of an active region streamer, indicating increased signal compared to the quiet Sun cases.

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arXiv2016

CHEERS Results from NGC 3393, II: Investigating the Extended Narrow Line Region using Deep Chandra Observations and Hubble Narrow Line Imaging

The CHandra Extended Emission Line Region Survey (CHEERS) is an X-ray study of nearby active galactic nuclei (AGN) designed to take full advantage of Chandra's unique angular resolution by spatially resolving feedback signatures and effects. In the second paper of a series on CHEERS target NGC 3393, we examine deep high-resolution Chandra images and compare them with Hubble narrow line images of [O III], [S II] and H$\alpha$, as well as previously-unpublished mid-ultraviolet (MUV) images. The X-rays provide unprecedented evidence that the S-shaped arms which envelope the nuclear radio outflows extend only $\lesssim$0.2'' ($\lesssim50 pc$) across. The high-resolution multiwavelength data suggest that the ENLR is a complex multi-phase structure in the circumnuclear ISM. Its ionization structure is highly stratified with respect to outflow-driven bubbles in the bicone and varies dramatically on scales of ~10 pc. Multiple findings show likely contributions from shocks to the feedback in regions where radio outflows from the AGN most directly influence the ISM. These findings include H$\alpha$ evidence for gas compression and extended MUV emission, and are in agreement with existing STIS kinematics. Extended filamentary structure in the X-rays and optical suggests the presence of an undetected plasma component, whose existence could be tested with deeper radio observations.

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arXiv2016

Mapping Seyfert and LINER Excitation Modes in the Inner kpc of NGC 3393

We have mapped the extended narrow line region (ENLR) of NGC 3393 on scales of $r\lesssim4^{\prime\prime}$ ($\sim1\,$kpc) from the nucleus using emission line images of H$\alpha\,\lambda6563$, [O III]$\lambda5007$, and [S II]$\lambda\lambda6717,6731$ taken with HST as part of the CHandra survey of Extended Emission line Regions in nearby Seyfert galaxies (CHEERS). By mapping these lines onto a spatially resolved Baldwin-Phillips-Terlevich (BPT) diagram, we investigate the impact of feedback from a Compton-thick AGN on its circumnuclear ISM. We find the expected Seyfert-like emission within the ionization bicone ($\lesssim3^{\prime\prime}$; 770 pc). We also find a new, figure 8 shaped LINER cocoon enveloping the bicone and defining a sharp ($\lesssim100\;$pc) transition between higher and lower ionization zones. These data illustrate the morphological dependence of ionization states of the ENLR relative to bicone and host gas geometries.

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