Emission-line objects from ALFALFA H{alpha} survey Virtual Observatory Resource

Authors
  1. Kellar J.A.
  2. Salzer J.J.
  3. Wegner G.
  4. Gronwall C.
  5. Williams A.
  6. Published by
    CDS
Abstract

During a wide-field narrowband H{alpha} imaging survey, we noted the presence of numerous isolated emission-line point sources in the data. These objects could represent ultra-low-luminosity galaxies at low-redshift (detection via H{alpha}), isolated extragalactic HII regions associated with the galaxy targeted by the original observation, or background galaxies or QSOs where strong emission lines (most often [OIII]{lambda}5007) redshift into our narrowband filter. We have carried out a systematic search for these "H{alpha} dots" in over 200 15x15arcmin fields. To date we have cataloged 61 candidate emission-line sources in roughly 11.7deg^2^. The sample has a median R magnitude of 19.5, and detects objects as faint as R=22.6. Follow-up spectroscopy reveals that ~85% of the candidates are bona fide emission-line objects, with roughly 60% of the real sources being lower-redshift objects (detection via H{alpha}) and 40% being higher-redshift objects detected via [OIII] emission or some other emission line. Here we present the results of our initial survey and follow-up spectroscopy. We use our sample to study the properties (including star-formation rates and metal abundances) of low-luminosity star-forming galaxies in the nearby universe and of low-metallicity star-forming galaxies at z~0.33.

Keywords
  1. spectroscopy
  2. redshifted
  3. seyfert-galaxies
  4. quasars
  5. metallicity
  6. line-intensities
Bibliographic source Bibcode
2012AJ....143..145K
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/143/145
IVOA Identifier IVOID
ivo://CDS.VizieR/J/AJ/143/145
Document Object Identifer DOI
doi:10.26093/cds/vizier.51430145

Access

Web browser access HTML
http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/143/145
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/143/145
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/143/145
IVOA Table Access TAP
http://tapvizier.cds.unistra.fr/TAPVizieR/tap
Run SQL-like queries with TAP-enabled clients (e.g., TOPCAT).
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
http://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/143/145/Ha_dot?
https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/143/145/Ha_dot?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/143/145/Ha_dot?

History

2013-07-30T10:11:29Z
Resource record created
2013-07-30T10:11:29Z
Created
2017-06-21T08:22:00Z
Updated

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr