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We spoke with four researchers to understand the accessibility challenges in astronomy research, education and outreach for blind and visually impaired (BVI) persons, as well as solutions to these challenges and how it innovates data analysis methods for all astronomers. Those interviewed: Nicolas Bonne (University of Portsmouth); Cheryl Fogle-Hatch (Museum Senses); Garry Foran (Swinburne University of Technology) and Enrique Perez Montero (Instituto de Astrof\'isica de Andaluc\'ia)., Comment: Accepted for publication in Nature Astronomy. A Word document (more accessible with screen readers) is available under 'ancillary files'. This is the author's own version (it is not the Version of Record and does not reflect post-acceptance improvements, or any corrections.) The Version of Record will be available with doi:10.1038/s41550-022-01691-2

The dynamics of gravitating astrophysical systems such as black holes and neutron stars are fascinatingly complex, offer some of nature's most spectacular phenomena, and capture the public's imagination in ways that few subjects can. Here, we describe {\it AstroDance}, a multi-media project to engage deaf and hard-of-hearing (DHH) students in astronomy and gravitational physics. {\it AstroDance} incorporates multiple means of representation of scientific concepts and was performed primarily for secondary and post-secondary audiences at $\sim$20 venues in the northeastern US prior to the historic first detection of gravitational waves. As part of the {\it AstroDance} project, we surveyed $\sim$1000 audience members roughly split evenly between hearing and DHH audience members. While both groups reported statistically equivalent high-rates of enjoyment of the performance, the DHH group reported an increase in how much they learned about science at a statistically significant rate compared to the hearing audience. Our findings suggest that multi-sensory approaches benefit both hearing and deaf audiences and enable accessible participation for broader groups., Comment: Accepted to Journal of Science Education for Students with Disabilities

(Abridged) In this white paper, we outline the major barriers to access within the educational and professional practice of astronomy. We present current best practices for inclusivity and accessibility, including classroom practices, institutional culture, support for infrastructure creation, hiring processes, and outreach initiatives. We present specific ways--beyond simple compliance with the ADA--that funding agencies, astronomers, and institutions can work together to make astronomy as a field more accessible, inclusive, and equitable. In particular, funding agencies should include the accessibility of institutions during proposal evaluation, hold institutions accountable for inaccessibility, and support efforts to gather data on the status and progress of astronomers and astronomy students with disabilities., Comment: 10 pages, 1 figure, Astro2020 APC White paper, State of the Profession Consideration

We present Chandra and XMM-Newton X-ray, VLA radio, and optical observations of three candidate Compact Steep Spectrum (CSS) radio galaxies. CSS sources are galactic scale and are presumably driving a shock through the ISM of their host galaxy. B3 1445+410 is a low excitation emission line CSS radio galaxy with possibly a hybrid Fanaroff-Riley FRI/II (or Fat Double) radio morphology. The Chandra observations reveal a point-like source which is well fit with a power law consistent with emission from a Doppler boosted core. 3C 268.3 is a CSS broad line radio galaxy whose Chandra data are consistent spatially with a point source centered on the nucleus and spectrally with a double power-law model. PKS B1017-325 is a low excitation emission line radio galaxy with a bent double radio morphology. While from our new spectroscopic redshift, PKS B1017-325 falls outside the formal definition of a CSS, the XMNM-Newton observations are consistent with ISM emission with either a contribution from hot shocked gas or non-thermal jet emission. We compile selected radio and X-ray properties of the nine bona fide CSS radio galaxies with X-ray detections so far. We find that 2/9 show X-ray spectroscopic evidence for hot shocked gas. We note that the counts in the sources are low and the properties of the 2 sources with evidence for hot shocked gas are typical of the other CSS radio galaxies. We suggest that hot shocked gas may be typical of CSS radio galaxies due to their propagation through their host galaxies., Comment: 15 pages, 12 figures. Accepted for publication in the Astrophysical Journal

We present the results of high resolution VLBI observations at 1.6 and 4.9 GHz of the radio-loud Seyfert galaxy, Mrk 6. These observations are able to detect a compact radio core in this galaxy for the first time. The core has an inverted spectral index ($\alpha^{1.6}_{4.9}$=+1.0$\pm$0.2) and a brightness temperature of $1\times10^8$ K. Three distinct radio components which resemble jet elements and/or hot spots, are also detected. The position angles of these elongated jet elements point, not only to a curved jet in Mrk 6, but also towards a connection between the AGN and the kpc-scale radio lobes/bubbles in this galaxy. Firmer constraints on the star formation rate provided by new Herschel observations (SFR $<0.8$ M$_\sun$ yr$^{-1}$) make the starburst-wind powered bubble scenario implausible. From plasma speeds obtained via prior Chandra X-ray observations, and ram pressure balance arguments for the ISM and radio bubbles, the north-south bubbles are expected to take $7.5\times10^6$ yr to form, and the east-west bubbles $1.4\times10^6$ yr. We suggest that the jet axis has changed at least once in Mrk 6 within the last $\approx10^7$ yr. A comparison of the nuclear radio-loudness of Mrk 6 and a small sample of Seyfert galaxies with a subset of low-luminosity FRI radio galaxies reveals a continuum in radio properties., Comment: 17 pages, 8 figures, MNRAS, accepted for publication

(ABRIDGED) We present here the results from new Very Long Baseline Array observations at 1.6 and 5 GHz of 19 galaxies of a complete sample of 21 UGC FRI radio galaxies. New Chandra data of two sources, viz., UGC00408 and UGC08433, are combined with the Chandra archival data of 13 sources. The 5 GHz observations of ten "core-jet" sources are polarization-sensitive, while the 1.6 GHz observations constitute second epoch total intensity observations of nine "core-only" sources. Polarized emission is detected in the jets of seven sources at 5 GHz, but the cores are essentially unpolarized, except in M87. Polarization is detected at the jet edges in several sources, and the inferred magnetic field is primarily aligned with the jet direction. This could be indicative of magnetic field "shearing" due to jet-medium interaction, or the presence of helical magnetic fields. The jet peak intensity $I_\nu$ falls with distance $d$ from the core, following the relation, $I_\nu\propto d^a$, where $a$ is typically -1.5. Assuming that adiabatic expansion losses are primarily responsible for the jet intensity "dimming", two limiting cases are considered: [1] the jet has a constant speed on parsec-scales and is expanding gradually such that the jet radius $r\propto d^0.4$; this expansion is however unobservable in the laterally unresolved jets at 5 GHz, and [2] the jet is cylindrical and is accelerating on parsec-scales. Accelerating parsec-scale jets are consistent with the phenomenon of "magnetic driving" in Poynting flux dominated jets. Chandra observations of 15 UGC FRIs detect X-ray jets in nine of them. The high frequency of occurrence of X-ray jets in this complete sample suggests that they are a signature of a ubiquitous process in FRI jets., Comment: 42 pages, 18 figures, accepted for publication in ApJ

We present new Spitzer IRS spectroscopy of Cygnus A, one of the most luminous radio sources in the local universe. Data on the inner 20" are combined with new reductions of MIPS and IRAC photometry as well as data from the literature to form a radio through mid-infrared spectral energy distribution (SED). This SED is then modeled as a combination of torus reprocessed active galactic nucleus (AGN) radiation, dust enshrouded starburst, and a synchrotron jet. This combination of physically motivated components successfully reproduces the observed emission over almost 5 dex in frequency. The bolometric AGN luminosity is found to be 10^12 L_\odot (90% of LIR), with a clumpy AGN-heated dust medium extending to \sim130 pc from the supermassive black hole. Evidence is seen for a break or cutoff in the core synchrotron emission. The associated population of relativistic electrons could in principle be responsible for some of the observed X-ray emission though the synchrotron self-Compton mechanism. The SED requires a cool dust component, consistent with dust-reprocessed radiation from ongoing star formation. Star formation contributes at least 6 \times 10^10 L_\odot to the bolometric output of Cygnus A, corresponding to a star formation rate of \sim10 M_\odot yr-1., Comment: to appear in 01 Feb 2012 issue of ApJ (745-2). 13 pages, 9 figures

Quillen et al. and O'Dea et al. carried out a Spitzer study of a sample of 62 brightest cluster galaxies (BCGs) from the ROSAT Brightest Cluster Sample chosen based on their elevated H-alpha flux. We present Hubble Space Telescope Advanced Camera for Surveys (ACS) far ultraviolet (FUV) images of the Ly-alpha and continuum emission of the luminous emission-line nebulae in 7 BCGs found to have an infrared excess. We confirm that the BCGs are actively forming stars suggesting that the IR excess seen in these BCGs is indeed associated with star formation. The FUV continuum emission extends over a region of ~7-28 kpc (largest linear size) and even larger in Ly-alpha. The young stellar population required by the FUV observations would produce a significant fraction of the ionizing photons required to power the emission line nebulae. Star formation rates estimated from the FUV continuum range from ~3 to ~14 times lower than those estimated from the IR, however both the Balmer decrement in the central few arcseconds and detection of CO in most of these galaxies imply that there are regions of high extinction that could have absorbed much of the FUV continuum. Analysis of archival VLA observations reveals compact radio sources in all 7 BCGs and kpc scale jets in Abell 1835 and RXJ 2129+00. The four galaxies with archival deep Chandra observations exhibit asymmetric X-ray emission, the peaks of which are offset from the center of the BCGs by ~10 kpc on average. A low feedback state for the AGN could allow increased condensation of the hot gas into the center of the galaxy and the feeding of star formation., Comment: Accepted for publication in The Astrophysical Journal

We present an analysis of Spitzer IRS spectroscopy of 83 active galaxies from the extended 12 micron sample. We find rank correlations between several tracers of star formation which suggest that (1) the PAH feature is a reliable tracer of star formation, (2) there is a significant contribution to the heating of the cool dust by stars, (3) the H$_2$ emission is also primarily excited by star formation. The 55-90 vs. 20-30 spectral index plot is also a diagnostic of the relative contribution of Starburst to AGN. We see there is a large change in spectral index across the sample. Thus, the contribution to the IR spectrum from the AGN and starburst components can be comparable in magnitude but the relative contribution also varies widely across the sample. We find rank correlations between several AGN tracers. We search for correlations between AGN and Starburst tracers and we conclude that the AGN and Starburst tracers are not correlated. This is consistent with our conclusion that the relative strength of the AGN and Starburst components varies widely across the sample. Thus, there is no simple link between AGN fueling and Black Hole Growth and star formation in these galaxies. The distribution of Sil 10 micron and 18 micron strengths is consistent with the clumpy torus models of Sirocky et al. We find a rank correlation between the [NeV] 14 micron line and the 6.7 micron continuum which may be due to an extended component of hot dust. The Sy 2s with a Hidden Broad Line Region (HBLR) have a higher ratio of AGN to Starburst contribution to the SED than Sy 2s without an HBLR. This may contribute to the detection of the HBLR in polarized light. The Sy 2s with an HBLR are more similar to the Sy 1s than they are to the Sy 2s without an HBLR.

We present 19 nearby (z<0.3) 3CR radio galaxies imaged at low- and high-excitation as part of a Cycle 15 Hubble Space Telescope snapshot survey with the Advanced Camera for Surveys. These images consist of exposures of the H-alpha (6563 \AA, plus [NII] contamination) and [OIII] 5007 \AA emission lines using narrow-band linear ramp filters adjusted according to the redshift of the target. To facilitate continuum subtraction, a single-pointing 60 s line-free exposure was taken with a medium-band filter appropriate for the target's redshift. We discuss the steps taken to reduce these images independently of the automated recalibration pipeline so as to use more recent ACS flat-field data as well as to better reject cosmic rays. We describe the method used to produce continuum-free (pure line-emission) images, and present these images along with qualitative descriptions of the narrow-line region morphologies we observe. We present H-alpha+[NII] and [OIII] line fluxes from aperture photometry, finding the values to fall expectedly on the redshift-luminosity trend from a past HST/WFPC2 emission line study of a larger, generally higher redshift subset of the 3CR. We also find expected trends between emission line luminosity and total radio power, as well as a positive correlation between the size of the emission line region and redshift. We discuss the associated interpretation of these results, and conclude with a summary of future work enabled by this dataset., Comment: 18 pages, 12 figures, accepted for publication in ApJS

The infrared is a key wavelength regime for probing the dusty, obscured nuclear regions of active galaxies. We present results from an infrared study of 87 nearby Seyfert galaxies using the Spitzer Space Telescope and ground-based telescopes. Combining detailed modelling of the 3 - 100 micron spectral energy distributions with mid-IR spectral diagnostics and near-infrared observations, we find broad support for the unified model of AGNs. The IR emission of Seyfert 1s and 2s is consistent with their having the same type of central engine viewed at a different orientation. The nature of the putative torus is becoming clearer; in particular we present evidence that it is likely a clumpy medium. Mid-infrared correlations between tracers of star formation and AGN ionizing luminosity reveal the starburst-AGN connection implied by the black hole/bulge mass relation, however it is not yet clear if this is due to feedback., Comment: Talk given at "The Central Kiloparsec: Active Galactic Nuclei and Their Hosts", Ierapetra, Crete, 4-6 June, 2008. To appear in Volume 79 of the Memorie della Societa Astronomica Italiana. 4 pages, 5 figures

Quillen et al.(2007) presented an imaging survey with the {\it Spitzer Space Telescope} of 62 brightest cluster galaxies with optical line emission located in the cores of X-ray luminous clusters. They found that at least half of these sources have signs of excess infrared emission. Here we discuss the nature of the IR emission and its implications for cool core clusters. The strength of the mid-IR excess emission correlates with the luminosity of the optical emission lines. Excluding the four systems dominated by an AGN, the excess mid-infrared emission in the remaining brightest cluster galaxies is likely related to star formation. The mass of molecular gas (estimated from CO observations) is correlated with the IR luminosity as found for normal star forming galaxies. The gas depletion time scale is about 1 Gyr. The physical extent of the infrared excess is consistent with that of the optical emission line nebulae. This supports the hypothesis that the star formation occurs in molecular gas associated with the emission line nebulae and with evidence that the emission line nebulae are mainly powered by ongoing star formation. We find a correlation between mass deposition rates (${\dot M}_X$) estimated from the X-ray emission and the star formation rate estimated from the infrared luminosity. The star formation rates are 1/10 to 1/100 of the mass deposition rates suggesting that the re-heating of the ICM is generally very effective in reducing the amount of mass cooling from the hot phase but not eliminating it completely.

We report on an imaging survey with the Spitzer Space Telescope of 62 brightest cluster galaxies with optical line emission. These galaxies are located in the cores of X-ray luminous clusters selected from the ROSAT All-Sky Survey. We find that about half of these sources have a sign of excess infrared emission; 22 objects out of 62 are detected at 70 microns, 18 have 8 to 5.8 micron flux ratios above 1.0 and 28 have 24 to 8 micron flux ratios above 1.0. Altogether 35 of 62 objects in our survey exhibit at least one of these signs of infrared excess. Four galaxies with infrared excesses have a 4.5/3.6 micron flux ratio indicating the presence of hot dust, and/or an unresolved nucleus at 8 microns. Three of these have high measured [OIII](5007A)/Hbeta flux ratios suggesting that these four, Abell 1068, Abell 2146, and Zwicky 2089, and R0821+07, host dusty active galactic nuclei (AGNs). 9 objects (including the four hosting dusty AGNs) have infrared luminosities greater than 10^11 L_sol and so can be classified as luminous infrared galaxies (LIRGs). Excluding the four systems hosting dusty AGNs, the excess mid-infrared emission in the remaining brightest cluster galaxies is likely related to star formation., Comment: accepted for publication in ApJS

(abridged) We analyze and model HST /STIS observations of a sample of 27 galaxies; 16 Fanaroff & Riley Type I radio galaxies and 11 (more) normal early-type galaxies. We focus here on what can be learned from the nuclear velocity dispersion (line width) of the gas as a complement to the many studies dealing with gas rotation velocities. We find that the dispersion in a STIS aperture of ~0.1''-0.2'' generally exceeds the large-scale stellar velocity dispersion of the galaxy. This is qualitatively consistent with the presence of central BHs, but raises the question whether the excess gas dispersion is of gravitational or non-gravitational origin and whether the implied BH masses are consistent with our current understanding of BH demography(as predicted by the M-sigma relation between BH mass and stellar velocity dispersion). To address this we construct dynamical models for the gas, both thin disk models and models with more general axis ratios and velocity anisotropies. For the normal galaxies the nuclear gas dispersions are adequately reproduced assuming disks around BHs with masses that follow the M-sigma relation. In contrast, the gas dispersions observed for the radio galaxies generally exceed those predicted by any of the models. We attribute this to the presence of non-gravitational motions in the gas that are similar to or larger than the gravitational motions. The non- gravitational motions are presumably driven by the active galactic nucleus (AGN), but we do not find a relation between the radiative output of the AGN and the non-gravitational dispersion. It is not possible to uniquely determine the BH mass for each galaxy from its nuclear gas dispersion. However, for the sample as a whole the observed dispersions do not provide evidence for significant deviations from the M-sigma relation., Comment: accepted for publication in the Astronomical Journal

Among radio galaxies containing nuclear dust disks, the bipolar jet axis is generally observed to be perpendicular to the disk major axis. The FR I radio source 3C 449 is an outlier to this statistical majority, as it possesses a nearly parallel jet/disk orientation on the sky. We examine the 600 pc dusty disk in this galaxy with images from the Hubble Space Telescope. We find that a colormap of the disk exhibits a twist in its isocolor contours (isochromes). We model the colormap by integrating galactic starlight through an absorptive disk, and find that the anomalous twist in the isochromes can be reproduced in the model with a vertically thin, warped disk. The model predicts that the disk is nearly perpendicular to the jet axis within 100 pc of the nucleus. We discuss physical mechanisms capable of causing such a warp. We show that precessional models or a torque on the disk arising from a possible binary black hole in the AGN causes precession on a timescale that is too long to account for the predicted disk morphology. However, we estimate that the pressure in the X-ray emitting interstellar medium is large enough to perturb the disk, and argue that jet-driven anisotropy in the excited ISM may be the cause of the warp. In this way, the warped disk in 3C 449 may be a new manifestation of feedback from an active galactic nucleus., Comment: Accepted for publication in ApJ

Immersive informal environments (such as summer camps, residential programs at museums and science centers, etc.) can provide a venue for young people to explore their scientific thinking in a less formalized context than is available in most traditional classrooms. While class instruction is beneficial for children to develop formal science skills and content knowledge, venues that offer more opportunities for experimentation and exploration can promote deeper understandings. In this article I explore the background of science learning and venues where this learning can take place followed by a review of the benefits and necessary components of well designed immersive informal programs., Comment: 7 pages

We present the results of the analysis of a set of medium resolution spectra, obtained by the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope, of the emission line gas present in the nuclei of a complete sample of 21 nearby, early-type galaxies with radio jets (the UGC FR-I Sample). For each galaxy nucleus we present spectroscopic data in the region of H-alpha and the dervived kinematics. We find that in 67% of the nuclei the gas appears to be rotating and, with one exception, the cases where rotation is not seen are either face on or have complex central morphologies. We find that in 62% of the nuclei the fit to the central spectrum is improved by the inclusion of a broad component. The broad components have a mean velocity dispersion of 1349 +/- 345 km\s and are redshifted from the narrow line components (assuming an origin in H-alpha) by 486 +/- 443 km\s., Comment: 119 pages, 26 figures, ApJS Accepted, version with full figures available at http://www.astro.columbia.edu/~jake/pub/fr1datapaper.pdf

The majority of nearby early-type galaxies contains detectable amounts of emission-line gas at their centers. The emission-line ratios and gas kinematics potentially form a valuable diagnostic of the nuclear activity and gravitational potential well. The observed central gas velocity dispersion often exceeds the stellar velocity dispersion. This could be due to either the gravitational potential of a black hole or turbulent shocks in the gas. Here we try to discriminate between these two scenarios., Comment: 5 pages, 2 figures. To appear in "Carnegie Observatories Astrophysics Series, Vol. 1: Coevolution of Black Holes and Galaxies," ed. L. C. Ho (Pasadena: Carnegie Observatories, http://www.ociw.edu/ociw/symposia/series/symposium1/proceedings.html)

(abridged) We investigate the kinematics of the central gas disk of the radio-loud elliptical galaxy NGC 4335, derived from HST/STIS long-slit spectroscopic observations of Halpha+[NII] along 3 parallel slit positions. The observed mean velocities are consistent with a rotating thin disk. We model the gas disk in the customary way. This sets a 3 sigma upper limit of 10^8 Msun on black hole mass, Mbh. The velocity dispersion at r <0.5'' is in excess of that predicted by the thin rotating disk model. This does not invalidate the model, if the excess dispersion is caused by localized turbulent motion in addition to bulk circular rotation. However, if instead the dispersion is caused by the BH potential then a mass Mbh ~ 6x10^8 Msun is inferred by modeling the central gas dispersion as due to an isotropic spherical distribution of collisionless gas cloudlets. The stellar kinematics for NGC 4335 are derived from a ground-based (WHT/ISIS) long-slit observation along the galaxy major axis. A two-integral model of the stellar dynamics yields Mbh >= 3x10^9 Msun. However, there is reason to believe that this model overestimates Mbh. Reported correlations between black hole mass and inner stellar velocity dispersion sigma predict Mbh to be >= 5.4x10^8 Msun in NGC 4335. If our standard thin disk modeling of the gas kinematics is valid, then NGC 4335 has an unusually low Mbh for its velocity dispersion. If, on the other hand, this approach is flawed, and provides an underestimate of Mbh, then black hole masses for other galaxies derived from HST gas kinematics with the same assumptions should be treated with caution., Comment: Article contains 40 pages, accepted for publication in AJ, scheduled for November issue

We present initial results of our analysis of line emission produced in gas disks found at the centers of a sample of nearby, radio galaxies with radio jets. We obtained data using STIS (The Space Telescope Imaging Spectrograph) at three parallel slit positions on the nucleus of each galaxy. This allows us to map the H$\alpha$ + [NII] flux, the gas radial velocity and the velocity dispersion. We find evidence of rotating disks in 11 of the sample galaxies and we can not currently rule out a rotating disk model for the remaining eight. For rotating systems, we find that the minimum central enclosed mass is greater than or similar to the predicted black hole mass based on ground-based stellar velocity dispersions. By modeling the gas dynamics we will go on to constrain the masses of the black holes. We will also investigate the properties of the gas disks themselves, giving us an insight into fueling, ionization mechanisms and the structure of the central regions., Comment: To appear in: "The central kpc of starbursts and AGN: the La Palma connection", Eds. J.H. Knapen, J.E. Beckman, I. Shlosman and T.J. Mahoney, ASP conf. series, in press (2001)

We have observed a complete sample of 21 nearby (D < 70h^{-1} Mpc) Fanaroff & Riley Type I galaxies with HST/WFPC2 and detected dust disks and lanes in 19 of them. The radio jets are roughly perpendicular to the dust which is used to constrain the Doppler boosting factors of the radio jet and cores. The VLBA core flux correlates with the central Halpha+[NII] flux which might indicate that the VLBA core is dominated by an isotropic component. Twelve galaxies show nuclear optical sources. We discuss various possible origins for this emission., Comment: 4 pages. Contributed talk at IAU Symposium 205: Galaxies and their Constituents at the Highest Angular Resolutions, Manchester UK, August 2000. Proceedings to be published by ASP, edited by R. Schilizzi, S. Vogel, F. Paresce, M. Elvis