J/ApJ/861/49 ALFALFA extragalactic HI source catalog (Haynes+, 2018)
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 Li
<Astrophys. J., 861, 49 (2018)>
=2018ApJ...861...49H 2018ApJ...861...49H
ADC_Keywords: Surveys ; H I data ; Galaxies, radio ; Redshifts ; Optical
Keywords: catalogs; galaxies: distances and redshifts; methods: data analysis;
radio lines: galaxies; surveys; techniques: imaging spectroscopy
Abstract:
We present the catalog of ∼31500 extragalactic HI line sources
detected by the completed Arecibo Legacy Fast ALFA (ALFALFA) survey
out to z<0.06, including both high signal-to-noise ratio (>6.5)
detections and ones of lower quality that coincide in both position
and recessional velocity with galaxies of known redshift. We review
the observing technique, data reduction pipeline, and catalog
construction process, focusing on details of particular relevance to
understanding the catalog's compiled parameters. We further describe
and make available the digital HI line spectra associated with the
cataloged sources. In addition to the extragalactic HI line
detections, we report nine confirmed OH megamasers (OHMs) and 10 OHM
candidates at 0.16<z<0.22 whose OH line signals are redshifted into
the ALFALFA frequency band. Because of complexities in data collection
and processing associated with the use of a feed-horn array on a
complex single-dish antenna in the terrestrial radio frequency
interference environment, we also present a list of suggestions and
caveats for consideration by users of the ALFALFA extragalactic
catalog for future scientific investigations.
Description:
The Arecibo Legacy Fast ALFA (ALFALFA) Survey used the seven-horn
Arecibo L-band Feed Array (ALFA) to map nearly 7000deg2 of high
Galactic latitude sky accessible to the Arecibo telescope over ∼4400
nighttime hours between 2005 and 2011.
As a complement to Jones+ (2018MNRAS.477....2J 2018MNRAS.477....2J), which presents the
derived HI mass function (HIMF) and its dependence on the local
environment, this paper presents the extragalactic HI catalog
extracted from the completed ALFALFA survey. Because of the
overlapping nature of the drift-scan survey and improved availability
of the public optical imaging used to identify optical counterparts
(OCs) of ALFALFA HI sources, this catalog, presented in Table 2,
supersedes and replaces previous releases
(Giovanelli+ 2007, J/AJ/133/2569 ; Kent+ 2008, J/AJ/136/713 ;
Saintonge+ 2008, J/AJ/135/588 ; Martin+ 2009, J/ApJS/183/214 ;
Stierwalt+ 2009, J/AJ/138/338 and Haynes+ 2011, J/AJ/142/170).
In addition to the catalog of ALFALFA HI line detections, nine sources
are identified with OH megamasers (OHMs), and 10 are flagged as being
OHM candidates.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 113 31502 ALFALFA extragalactic HI source catalog;
corrected version (August 2019)
table3.dat 107 19 ALFALFA OH megamaser (OHM) candidate catalog
sp/* . 31502 Individual spectra in FITS format
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Description of file:
In subdirectory sp, available on FTP, the FITS version of the HI line
spectra associated to Table 2 are available.
Each file contains a header with information on the file structure,
the ALFALFA survey and the HI line source.
Column descriptions:
1. Heliocentric velocity [km/s]
2. Radio frequency [MHz]
3. Flux Density [mJy]
4. Subtracted polynomial baseline fit [mJy]
5. Spectral weight [normalized]
The normalized spectral weight provides an indicator of the amount of
data excised from the final spectrum, typically due to the presence of
radio frequency interference.
Note that the baseline fit (Col. 4) has been subtracted to produce
Col. 3.
Note that spectral values (flux density and baseline) that are out of
range and/or associated with fully masked (weight=0)
frequency/velocity bins ("channels") are set to -999 rather than NaN
or some other value.
See also:
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
VIII/73 : HI Parkes All Sky Survey Catalogue (HIPASS) (Meyer+, 2004)
VIII/77 : HI spectral properties of galaxies (Springob+, 2005)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/AJ/117/2039 : Sc galaxies I photometry, 21cm data (Haynes+, 1999)
J/AJ/132/2596 : Spectroscopy of Ultraluminous IR galaxies (Darling+, 2006)
J/AJ/133/2569 : Arecibo legacy fast ALFA survey III. (Giovanelli+, 2007)
J/ApJ/655/144 : ACS Virgo Cluster Survey. XIII. (Mei+, 2007)
J/ApJS/172/599 : SFI++ II. A new I-band Tully-Fisher catalog (Springob+, 2007)
J/AJ/136/713 : Arecibo legacy fast ALFA survey. VI. (Kent+, 2008)
J/AJ/135/588 : Arecibo legacy fast ALFA survey V. (Saintonge+, 2008)
J/ApJS/183/214 : ALFALFA VIII. (Martin+, 2009)
J/AJ/138/338 : Arecibo Legacy Fast ALFA Survey. IX. (Stierwalt+, 2009)
J/AJ/142/170 : ALFALFA survey: α.40 HI source catalog (Haynes+, 2011)
J/AJ/143/133 : Dwarf galaxies from the ALFALFA survey (Huang+, 2012)
J/ApJ/768/77 : Ultra-compact HVCs from ALFALFA (Adams+, 2013)
J/AJ/146/86 : Cosmicflows-2 catalog (Tully+, 2013)
J/MNRAS/459/220 : Opt. redshifts of OH- and HI-emitting galaxies (Suess+, 2016)
J/A+A/597/A130 : HI and 250um images of the Virgo cirrus (Bianchi+, 2017)
J/ApJ/842/133 : HI-bearing ultra-diffuse ALFALFA galaxies (Leisman+, 2017)
http://egg.astro.cornell.edu/alfalfa/data/ : ALFALFA archive
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 6 I06 --- AGC [1/749512] UGC/AGC number (1)
8- 15 A8 --- Name Common name of the optical counterpart
17- 18 I2 h RAh [0/23] HI centroid hour of RA (J2000)
19- 20 I2 min RAm HI centroid minute of RA (J2000)
21- 24 F4.1 s RAs HI centroid second of RA (J2000)
25 A1 --- DE- HI centroid sign of Dec (J2000)
26- 27 I2 deg DEd HI centroid degree of Dec (J2000)
28- 29 I2 arcmin DEm HI centroid arcminute of Dec (J2000)
30- 31 I2 arcsec DEs HI centroid arcsecond of Dec (J2000)
33- 34 I2 h RAOh ? Optical counterpart hour of RA (J2000)
35- 36 I2 min RAOm ? Optical counterpart minute of RA (J2000)
37- 40 F4.1 s RAOs ? Optical counterpart second of RA (J2000)
41 A1 --- DEO- Optical counterpart sign of Dec (J2000)
42- 43 I2 deg DEOd ? Optical counterpart degree of Dec (J2000)
44- 45 I2 arcmin DEOm ? Opt. counterpart arcminute of Dec (J2000)
46- 47 I2 arcsec DEOs ? Opt. counterpart arcsecond of Dec (J2000)
49- 53 I5 km/s Vhel [-430/17823] Heliocentric velocity of
the HI profile midpoint
55- 57 I3 km/s W50 [9/885] Observed velocity width
at 50% of peak on either side
59- 61 I3 km/s e_W50 [1/296] Uncertainty in W50
63- 65 I3 km/s W20 [0/896] Observed velocity width
at 20% of peak on either side
67- 72 F6.2 Jy.km/s HIflux [-7.7/999.9] HI line flux density
74- 77 F4.2 Jy.km/s e_HIflux [0.02/1.2] Uncertainty in HIflux
79- 83 F5.1 --- SNR [1.2/964] Ratio of peak flux to rms noise
85- 89 F5.2 mJy rms [1.2/18] The RMS noise in the extracted
spectrum at 10 km/s resolution
91- 95 F5.1 Mpc Dist [0.3/259.6] Adopted distance,
where applicable
97-100 F4.1 Mpc e_Dist [0/31] Uncertainty in Dist
102-106 F5.2 [Msun] logMHI [3.7/11] log HI mass where distance has
been adopted
108-111 F4.2 [Msun] e_logMHI [0.04/1.2] Uncertainty in logMHI
113 I1 --- HI [1/2] HI source code (2)
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Note (1): A private database of extragalactic objects maintained by M.P. Haynes
and R. Giovanelli (see Cat. VIII/77). The AGC entry normally
corresponds to the optical counterpart except in the cases of HI
sources which cannot be associated with an optical object with any
high degree of probability.
Numbers lower than 100,000 are UGC numbers (Cat. VII/26).
Note (2): Code as follows:
1 = Source of significant S/N and high quality insuring reliability.
2 = Source of slightly lower S/N which coincides with an optical
counterpart of known, coincident redshift.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- AGC [102708/749309] AGC number
8- 35 A28 --- Name Common name
37- 38 I2 h RAh [0/23] Hour of HI right ascension (J2000)
39- 40 I2 min RAm Minute of HI right ascension (J2000)
41- 44 F4.1 s RAs Second of HI right ascension (J2000)
45 A1 --- DE- [+] Sign of HI declination (J2000)
46- 47 I2 deg DEd [5/35] Degree of HI declination (J2000)
48- 49 I2 arcmin DEm Arcminute of HI declination (J2000)
50- 51 I2 arcsec DEs Arcsecond of HI declination (J2000)
53- 54 I2 h RAOh Hour of optical right ascension (J2000)
55- 56 I2 min RAOm Minute of optical right ascension (J2000)
57- 60 F4.1 s RAOs Second of optical right ascension (J2000)
61 A1 --- DEO- Sign of optical declination (J2000)
62- 63 I2 deg DEOd Degree of optical declination (J2000)
64- 65 I2 arcmin DEOm Arcminute of optical declination (J2000)
66- 67 I2 arcsec DEOs Arcsecond of optical declination (J2000)
69- 75 F7.2 MHz Fcent [1360.7/1429.3] Frequency of the center
of the line signal
77- 79 I3 km/s W50 [23/613] Observed velocity width
at 50% of peak on either side
81- 84 F4.2 Jy.km/s HIflux [0.4/2.9] HI line flux density
86- 89 F4.1 --- SNR [4.3/17.4] Signal to noise ratio
91- 94 F4.2 mJy rms [1.9/2.8] RMS noise
96-103 F8.6 --- z [0.16/0.23]? Redshift
105-107 A3 --- f_AGC Flag(s) (1)
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Note (1): Flag as follows:
a = OHM confirmed by Suess et al. (2016, J/MNRAS/459/220).
b = OHM included in catalog of Darling & Giovanelli (2006, J/AJ/132/2596).
c = OC has coincident redshift in SDSS.
d = OHM discovered by Morganti et al. (2006MNRAS.371..157M 2006MNRAS.371..157M).
e = OC has no reported redshift; OH detection and/or redshift requires
confirmation.
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History:
* From electronic version of the journal for Tables
07-Aug-2019: Insert into VizieR
* 12-Aug-2019: Corrected version of Table 2 notified by the author,
uploaded at: http://egg.astro.cornell.edu/
alfalfa/data/a100files/a100.code12.table2.190808.mrt
Spectra downloaded from:
http://egg.astro.cornell.edu/alfalfa/data/a100files/a100.180315.fits.tar.gz
Acknowledgements:
Martha Haynes < haynes {at} astro.cornell.edu >
References:
Giovanelli et al. Paper I 2005AJ....130.2598G 2005AJ....130.2598G
Giovanelli et al. Paper II 2005AJ....130.2613G 2005AJ....130.2613G Cat. J/AJ/130/2613
Giovanelli et al. Paper III 2007AJ....133.2569G 2007AJ....133.2569G Cat. J/AJ/133/2569
Saintonge et al. Paper IV 2007AJ....133.2087S 2007AJ....133.2087S
Saintonge et al. Paper V 2008AJ....135..588S 2008AJ....135..588S Cat. J/AJ/135/588
Kent et al. Paper VI 2008AJ....136..713K 2008AJ....136..713K Cat. J/AJ/136/713
Kent et al. Paper VII 2009ApJ...691.1595K 2009ApJ...691.1595K
Martin et al. Paper VIII 2009ApJS..183..214M 2009ApJS..183..214M Cat. J/ApJS/183/214
Stierwalt et al. Paper IX 2009AJ....138..338S 2009AJ....138..338S Cat. J/AJ/138/338
Martin et al. Paper X 2010ApJ...723.1359M 2010ApJ...723.1359M
Haynes et al. alpha.40 2011AJ....142..170H 2011AJ....142..170H Cat. J/AJ/142/170
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 11-Jul-2019