This page hosts the public repository of datasets produced by the ALFALFA Team. Note that these datasets may contain updates/improvements on datasets contained in original publications. We try our best to document changes and all files contain a date which we strongly suggest you retain when you download them.
ALFALFA data products
The full ALFALFA dataset consists of Level 0, 1 and 2 datasets. The raw data (Level 0)
are archived at Arecibo. The Level 1 (calibrated, bandpass subtracted and RFI flagged)
drift scans and Level 2 (fully processed) data cubes are archived both at Cornell and at Arecibo.
The final data products include source catalogs with identified optical counterparts and (as of Nov 2020),
a cross-list to the SDSS is also provided. The spectra of galaxies listed
in the Extragalactic Source Catalog are available upon request (see below).
Note: The ALFALFA data and spectra are incorporated into the NASA Extragalactic Database (NED); to find
what's there, just follow
this
link. But, you can find both here, too!
The extragalactic source catalog is also available through the Vizier service as
J/ApJ/861/49.
"The Arecibo Legacy Fast ALFA Survey: The ALFALFA Extragalactic HI Source Catalog"
Haynes, M.P., Giovanelli, R., Kent, B.R., Adams, E.A.K., Balonek, T.J., Craig, D.W., Fertig, D., Finn, R., Giovanardi, C.,
Hallenbeck, G., Hess, K.M., Hoffman, G.L., Huang, S., Jones, M.G., Koopmann, R.A., Kornreich, D.A., Leisman, L.,
Miller, J., Moorman, C., O'Connor, J., O'Donoghue, A., Papastergis, E., Troischt, P. Stark, D. & Xiao, L. 2018 ApJ 861, 49.
ADSastro-ph/1805.11499
Table 2 of the paper by Haynes et al. (2018) presents the ALFALFA catalog
of extragalactic HI sources. The user is referred to that paper for a detailed
description of the data taking and reduction procedures and for discussion
of caveats involved in using this dataset, reviewing and expanding on discussions
presented previously in Giovanelli et al. (2005;
ADS) and Haynes et al. (2011;
ADS).
The values of parameters in Table 2 supercede those presented in earlier data
releases. Newly added to this Table are the HI line width at 20% of the peak
(W20) and the uncertainties in the distance (sigD) and the logarithm of the HI Mass
(sigMHI). The latter are identifical to those used in the paper analyzing
the ALFALFA HI mass function (Jones et al. 2018; ADS).
Brief description of contents of ASCII and CSV files.
See Haynes et al. (2018) for further details (Haynes et al. 2011 and Jones et al. 2018 also).
Due to file size, please contact Martha if you need the spectra.
"The ALFALFA-SDSS Galaxy Catalog"
Durbala, A., Finn, R.A., Crone Odekon, M., Haynes, M.P., Koopmann, R.A. & O'Donohue, A.A., 2020,
Astron. J. 160, 721 ADSastro-ph/2011.02588
Table 1 of the paper by Durbala et al. (2020) presents a cross reference of the ALFALFA Extragalactic Source catalog with the Sloan Digital Sky Survey (SDSS) and their basic properties. Table 2 of the same paper provides properties including absolute magnitudes, colors, stellar masses and star formation rates derived using various prescriptions as discussed in that paper.
Table 1. Basic optical properties of A100-SDSS galaxies
Older versions are available below but are superceded by
the above "α.100" files.
First-release version α.100 "A grids" data files
Below is the datafile, in ASCII and CSV formats, containint the 100% ALFALFA
catalog over the lowest velocity quadrant (cz < 3200 km/s), along with a file
explaining its contents. Users are strongly urged
to read all the details/disclaimers in the
α40 paper.
This dataset is not fully vetted, but is usable with minor caution.
Below is the datafile, in ASCII and CSV formats, containing the 70% ALFALFA
catalog α.70, along with a file explaining its contents. Users are strongly urged
to read all the details/disclaimers in the
α40 paper.
The datafiles associated with Tables 1, 2 and 3
of Haynes et al. 2011 (AJ 142, 170; ADS link)
containing the results of the
40% ALFALFA survey, also known as α.40, can be downloaded here. Users are strongly urged
to read all the details/disclaimers in the paper.
(Radio spectroscopy is fun, but it is not easy!)
The ALFALFA spectra (as well as nearly all of the older, targeted HI line spectra collected by us between 1981 and 2005) are available
through the NASA Extragalactic Database, on its
digital spectral search page. You can access
the HI digital spectra via NED as follows:
