Departures From Axisymmetric Morphology and Dynamics in Spiral Galaxies

New HI synthesis data have been obtained for six face-on galaxies with the Very Large Array. These data and reanalyses of three additional data sets make up a sample of nine face-on galaxies analyzed for deviations from axisymmetry in morphology and dynamics. This sample represents a subsample of galaxies already analyzed for morphological symmetry properties in the R-band. Four quantitative measures of dynamical nonaxisymmetry are compared to one another and to the quantitative measures of morphological asymmetry in HI and R-band to investigate the relationships between nonaxisymmetric morphology and dynamics. We find no significant relationship between asymmetric morphology and most of the dynamical measures in our sample. A possible relationship is found, however, between morphology and dynamical position angle differences between approaching and receding sides of the galaxy.Comment: 24 pages, 19 figures, AASTeX, accepted for publication in AJ, postscript figures available at ftp://culebra.tn.cornell.edu/pub/david/figures.tar.g

Radio Continuum Emission in Polar-Ring Galaxies

We have used the Very Large Array aperture synthesis telescope to conduct a radio continuum survey of polar-ring galaxies, at 20cm and 6cm. Forty objects were observed at 20cm with 5" resolution. Twenty (50%) of the program sources were detected at 20cm, down to our 5-sigma limit of 0.5 mJy/beam. This detection rate is similar to those in surveys with comparable sensitivity for early-type galaxies without polar rings. Sixteen of the objects we detected at 20cm were also observed at 6cm. We show radio continuum maps for the five objects in our sample that have noticeably extended emission. Our spatial resolution was sufficient to distinguish between emission originating in the host galaxy from that in the polar ring. The radio morphology of the extended sources, as well as the radio to far-infrared flux ratio and the radio spectral indices of our detected sources, indicate that star formation, not nuclear activity, is the dominant source of the radio continuum emission in polar-ring galaxies. However, the implied star-formation rates are modest, and only one of our sample galaxies will consume its supply of cool gas within 500 Myr.Comment: 21 pages, 7 figures. Produced with AASTeX 5.2 To appear in November 2004 Astronomical Journa

A Search for "Dwarf" Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies

We have completed an optical spectroscopic survey of the nuclear regions (r < 200 pc) of a large sample of nearby galaxies. Although the main objectives of the survey are to search for low-luminosity active galactic nuclei and to quantify their luminosity function, the database can be used for a variety of other purposes. This paper presents measurements of the spectroscopic parameters for the 418 emission-line nuclei, along with a compilation of the global properties of all 486 galaxies in the survey. Stellar absorption generally poses a serious obstacle to obtaining accurate measurement of emission lines in nearby galactic nuclei. We describe a procedure for removing the starlight from the observed spectra in an efficient and objective manner. The main parameters of the emission lines (intensity ratios, fluxes, profile widths, equivalent widths) are measured and tabulated, as are several stellar absorption-line and continuum indices useful for studying the stellar population. Using standard nebular diagnostics, we determine the probable ionization mechanisms of the emission-line objects. The resulting spectral classifications provide extensive information on the demographics of emission-line nuclei in the local universe. This new catalog contains over 200 objects showing spectroscopic evidence for recent star formation and an equally large number of active galactic nuclei, including 46 which show broad H-alpha emission. These samples will serve as the basis of future studies of nuclear activity in nearby galaxies.Comment: To appear in the Astrophysical Journal Supplements. LaTex, 31 pages, plus an additional 23 figures and 5 tables. AASTex macro aaspp4.st

The Updated Zwicky Catalog (UZC)

The Zwicky Catalog of galaxies (ZC), with m_Zw<=15.5mag, has been the basis for the Center for Astrophysics (CfA) redshift surveys. To date, analyses of the ZC and redshift surveys based on it have relied on heterogeneous sets of galaxy coordinates and redshifts. Here we correct some of the inadequacies of previous catalogs by providing: (1) coordinates with <~2 arcsec errors for all of the Nuzc catalog galaxies, (2) homogeneously estimated redshifts for the majority (98%) of the data taken at the CfA (14,632 spectra), and (3) an estimate of the remaining "blunder" rate for both the CfA redshifts and for those compiled from the literature. For the reanalyzed CfA data we include a calibrated, uniformly determined error and an indication of the presence of emission lines in each spectrum. We provide redshifts for 7,257 galaxies in the CfA2 redshift survey not previously published; for another 5,625 CfA redshifts we list the remeasured or uniformly re-reduced value. Among our new measurements, Nmul are members of UZC "multiplets" associated with the original Zwicky catalog position in the coordinate range where the catalog is 98% complete. These multiplets provide new candidates for examination of tidal interactions among galaxies. All of the new redshifts correspond to UZC galaxies with properties recorded in the CfA redshift compilation known as ZCAT. About 1,000 of our new measurements were motivated either by inadequate signal-to-noise in the original spectrum or by an ambiguous identification of the galaxy associated with a ZCAT redshift. The redshift catalog we include here is ~96% complete to m_Zw<=15.5, and ~98% complete (12,925 galaxies out of a total of 13,150) for the RA(1950) ranges [20h--4h] and [8h--17h] and DEC(1950) range [-2.5d--50d]. (abridged)Comment: 34 pp, 7 figs, PASP 1999, 111, 43

Cardiac Function and Serum Biomarkers throughout Staged Fontan Palliation:A Prospective Observational Study

Fontan patients undergo multiple cardiothoracic surgeries in childhood. Following these procedures, ventricular function is temporarily decreased, and recovers over months. This is presumably related to cardiopulmonary bypass, but this is incompletely understood. Throughout the Fontan palliation, cardiac function is also affected by volume unloading. We aimed to gain insight into the biological processes related to impaired ventricular function and recovery following Fontan palliations using a panel of biomarkers. Furthermore, we described changes in ventricular function across the Fontan palliation due to volume unloading. We performed a prospective multicenter observational study in patients undergoing partial (PCPC) or total cavo-pulmonary connection (TCPC). Patients underwent assessment-including echocardiography and blood sampling-before surgery (T1), at first follow-up (T2), and 1 year after their procedures (T3). Blood samples were analyzed using a biomarker panel (OLINK CVD-III). Ninety-two biomarkers were expressed as principal components (PC) to limit multiple statistical testing. We included 32 PCPC patients aged 7.2 [5.3-10.3] months, and 28 TCPC patients aged 2.7 [2.2-3.8] years. The single ventricular longitudinal strain (SV GLS) temporarily decreased for PCPC patients at T2 (-15.1 ± 5.6 (T1) to -13.5 ± 5.2 (T2) to -17.3 ± 4.5 (T3), p &lt; 0.047 for all differences), but not following TCPC. The serum biomarkers were expressed as 4 PCs. PC1, including biomarkers of cell-cell adhesion, was not related to any patient characteristic. PC2, including biomarkers of superoxide anion regulation, increased at T2. PC3, including biomarkers of cardiovascular development, related to the stage of Fontan palliation. PC4 was of uncertain biological or clinical significance. No PC was found that related to ventricular performance. The SV GLS was temporarily diminished following PCPC, but not following TCPC. Several biomarkers were related to post-operative stress and adaptation to the PCPC or TCPC circulation, but none were related to the outcome. </p

Cardiac Function and Serum Biomarkers throughout Staged Fontan Palliation:A Prospective Observational Study

Fontan patients undergo multiple cardiothoracic surgeries in childhood. Following these procedures, ventricular function is temporarily decreased, and recovers over months. This is presumably related to cardiopulmonary bypass, but this is incompletely understood. Throughout the Fontan palliation, cardiac function is also affected by volume unloading. We aimed to gain insight into the biological processes related to impaired ventricular function and recovery following Fontan palliations using a panel of biomarkers. Furthermore, we described changes in ventricular function across the Fontan palliation due to volume unloading. We performed a prospective multicenter observational study in patients undergoing partial (PCPC) or total cavo-pulmonary connection (TCPC). Patients underwent assessment—including echocardiography and blood sampling—before surgery (T1), at first follow-up (T2), and 1 year after their procedures (T3). Blood samples were analyzed using a biomarker panel (OLINK CVD-III). Ninety-two biomarkers were expressed as principal components (PC) to limit multiple statistical testing. We included 32 PCPC patients aged 7.2 [5.3–10.3] months, and 28 TCPC patients aged 2.7 [2.2–3.8] years. The single ventricular longitudinal strain (SV GLS) temporarily decreased for PCPC patients at T2 (−15.1 ± 5.6 (T1) to −13.5 ± 5.2 (T2) to −17.3 ± 4.5 (T3), p &lt; 0.047 for all differences), but not following TCPC. The serum biomarkers were expressed as 4 PCs. PC1, including biomarkers of cell–cell adhesion, was not related to any patient characteristic. PC2, including biomarkers of superoxide anion regulation, increased at T2. PC3, including biomarkers of cardiovascular development, related to the stage of Fontan palliation. PC4 was of uncertain biological or clinical significance. No PC was found that related to ventricular performance. The SV GLS was temporarily diminished following PCPC, but not following TCPC. Several biomarkers were related to post-operative stress and adaptation to the PCPC or TCPC circulation, but none were related to the outcome.</p

The Detection of a Massive Chain of Dark H i Clouds in the GAMA G23 Field

We report on the detection of a large, extended H i cloud complex in the Galaxy and Mass Survey G23 field, located at a redshift of z ∼0.03, observed as part of the MeerKAT Habitat of Galaxies Survey campaign (a pilot survey to explore the mosaicing capabilities of the MeerKAT telescope). The cloud complex, with a total mass of 1010.0 M, lies in proximity to a large galaxy group with M dyn ∼1013.5 M. We identify seven H peak concentrations, interconnected as a tenuous chain structure, extending ∼400 kpc from east to west, with the largest (central) concentration containing 109.7 M in H gas distributed across 50 kpc. The main source is not detected in ultraviolet, optical, or infrared imaging. The implied gas mass-to-light ratio (M H I/L r) is extreme (>1000) even in comparison to other dark clouds. The complex has very little kinematic structure (110 km s-1), making it difficult to identify cloud rotation. Assuming pressure support, the total mass of the central concentration is > 1010.2 M, while a lower limit to the dynamical mass in the case of full rotational support is 1010.4 M. If the central concentration is a stable structure, it has to contain some amount of unseen matter, but potentially less than is observed for a typical galaxy. It is, however, not clear whether the structure has any gravitationally stable concentrations. We report a faint UV-optical-infrared source in proximity to one of the smaller concentrations in the gas complex, leading to a possible stellar association. The system nature and origins is enigmatic, potentially being the result of an interaction with or within the galaxy group it appears to be associated with

Relativistic supernova 2009bb exploded close to an atomic gas cloud

Context. The host galaxies of gamma-ray bursts (GRBs) have been claimed to have experienced a recent inflow of gas from the intergalactic medium. This is because their atomic gas distribution is not centred on their optical emission and because they are deficient in molecular gas given their high star formation rates (SFRs). Similar studies have not been conducted for host galaxies of relativistic supernovae (SNe), which may have similar progenitors. Aims. The potential similarity of the powering mechanisms of relativistic SNe and GRBs allowed us to make a prediction that relativistic SNe are born in environments similar to those of GRBs, that is, ones which are rich in atomic gas. Here we embark on testing this hypothesis by analysing the properties of the host galaxy NGC 3278 of the relativistic SN 2009bb. This is the first time the atomic gas properties of a relativistic SN host are provided and the first time resolved 21 cm-hydrogen-line (HâI) information is provided for a host of an SN of any type in the context of the SN position. Methods. We obtained radio observations with the Australia Telescope Compact Array (ATCA) covering the Hâ I line, and optical integral field unit spectroscopy observations with the Multi Unit Spectroscopic Explorer (MUSE) at the Very Large Telescope (VLT). Moreover, we analysed archival carbon monoxide (CO) and multi-wavelength data for this galaxy. Results. The atomic gas distribution of NGC 3278 is not centred on the optical galaxy centre, but instead around a third of atomic gas resides in the region close to the SN position. This galaxy has a few times lower atomic and molecular gas masses than predicted from its SFR. Its specific SFR (sSFR â SFR/M) is approximately two to three times higher than the main-sequence value, placing it at the higher end of the main sequence, towards starburst galaxies. SN 2009bb exploded close to the region with the highest SFR density and the lowest age, as evident from high Hα EW, corresponding to the age of the stellar population of ~5.5 Myr. Assuming this timescale was the lifetime of the progenitor star, its initial mass would have been close to ~36 M. Conclusions. As for GRB hosts, the gas properties of NGC 3278 are consistent with a recent inflow of gas from the intergalactic medium, which explains the concentration of atomic gas close to the SN position and the enhanced SFR. Super-solar metallicity at the position of the SN (unlike for most GRBs) may mean that relativistic explosions signal a recent inflow of gas (and subsequent star formation), and their type (GRBs or SNe) is determined either (i) by the metallicity of the inflowing gas, so that metal-poor gas results in a GRB explosion and metal-rich gas (for example a minor merger with an evolved galaxy or re-Accretion of expelled gas) results in a relativistic SN explosion without an accompanying GRB, or (ii) by the efficiency of gas mixing (efficient mixing for SN hosts leading to a quick disappearance of metal-poor regions), or (iii) by the type of the galaxy (more metal-rich galaxies would result in only a small fraction of star formation being fuelled by metal-poor gas).© ESO 2018.We thank Joanna Baradziej for help to improve this paper, and Giuliano Pignata, Carlos Contreras, and Maximilian Stritzinger for sharing the H-band image. M.J.M. acknowledges the support of the National Science Centre, Poland, through the POLONEZ grant 2015/19/P/ST9/04010; and the UK Science and Technology Facilities Council; this project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 665778. J.H. was supported by a VILLUM FONDEN Investigator grant (project number 16599). L.G. was supported in part by the US National Science Foundation under Grant AST-1311862. L.K.H. acknowledges funding from the INAF PRIN-SKA program 1.05.01.88.04. A.d.U.P. acknowledges support from the European Commission (FP7-PEOPLE-2012-CIG 322307) and from the Spanish project AYA2012-39362-C02-02. S.D.V. is supported by the French National Research Agency (ANR) under contract ANR-16-CE31-0003 BEaPro. The Australia Telescope Compact Array is part of the Australia Telescope National Facility, which is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme(s) 095.D-0172(A). This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. We acknowledge the usage of the Hyper-Leda database (http://leda.univ-lyon1.fr). This research has made use of the GHostS database (http://www.grbhosts.org), which is partly funded by Spitzer/NASA grant RSA Agreement No. 1287913; the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration; SAOImage DS9, developed by Smithsonian Astrophysical Observatory (Joye & Mandel 2003); and NASA's Astrophysics Data System Bibliographic Services.Peer reviewe

Planetary Nebulae in Face-On Spiral Galaxies. I. Planetary Nebula Photometry and Distances

As the first step to determine disk mass-to-light ratios for normal spiral galaxies, we present the results of an imaging survey for planetary nebulae (PNe) in six nearby, face-on systems: IC 342, M74 (NGC 628), M83 (NGC 5236), M94 (NGC 4736), NGC 5068, and NGC 6946. Using Blanco/Mosaic II and WIYN/OPTIC, we identify 165, 153, 241, 150, 19, and 71 PN candidates, respectively, and use the Planetary Nebula Luminosity Function (PNLF) to obtain distances. For M74 and NGC 5068, our distances of 8.6 +/- 0.3 Mpc and 5.4 +0.2/-0.4 Mpc are the first reliable estimates to these objects; for IC 342 (3.5 +/- 0.3 Mpc), M83 (4.8 +/- 0.1 Mpc), M94 (4.4 +0.1/-0.2 Mpc), and NGC 6946 (6.1 +/- 0.6 Mpc) our values agree well with those in the literature. In the larger systems, we find no evidence for any systematic change in the PNLF with galactic position, though we do see minor field-to-field variations in the luminosity function. In most cases, these changes do not affect the measurement of distance, but in one case the fluctuations result in a ~0.2 mag shift in the location of the PNLF cutoff. We discuss the possible causes of these small-scale changes, including internal extinction in the host galaxies and age/metallicity changes in the underlying stellar population.Comment: Accepted for publication in ApJ; 23 pages, 7 figures, 5 table

WALLABY Pilot Survey: An 'Almost' Dark Cloud near the Hydra Cluster

We explore the properties of an 'almost' dark cloud of neutral hydrogen (HI) using data from the Widefield ASKAP L-band Legacy All-sky Survey (WALLABY). Until recently, WALLABY J103508-283427 (also known as H1032-2819 or LEDA 2793457) was not known to have an optical counterpart, but we have identified an extremely faint optical counterpart in the DESI Legacy Imaging Survey Data Release 10. We measured the mean g-band surface brightness to be $27.0\pm0.3$ mag arcsec$^{-2}$. The WALLABY data revealed the cloud to be closely associated with the interacting group Klemola 13 (also known as HIPASS J1034-28 and the Tol 9 group), which itself is associated with the Hydra cluster. In addition to WALLABY J103508-283427/H1032-2819, Klemola 13 contains ten known significant galaxies and almost half of the total HI gas is beyond the optical limits of the galaxies. By combining the new WALLABY data with archival data from the Australia Telescope Compact Array (ATCA), we investigate the HI distribution and kinematics of the system. We discuss the relative role of tidal interactions and ram pressure stripping in the formation of the cloud and the evolution of the system. The ease of detection of this cloud and intragroup gas is due to the sensitivity, resolution and wide field of view of WALLABY, and showcases the potential of the full WALLABY survey to detect many more examples.Comment: 13 pages, 7 figures, accepted for publication in MNRA