J/A+A/704/A252 The 2MZoA catalogue (Schroeder, 2025)
Supplementing the 2MRS survey: The 2MZoA catalogue.
Schroeder A.C.
<Astron. Astrophys. 704, A252 (2025)>
=2025A&A...704A.252S 2025A&A...704A.252S (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, IR ; Photometry, infrared ; Radial velocities ;
Optical ; H I data
Keywords: catalogs - galaxies: general - galaxies: photometry -
infrared: galaxies
Abstract:
We present a homogeneous 2MASX galaxy catalogue at low Galactic
latitudes (|b|≤10.0deg, called Zone of Avoidance, ZoA) which is
complete to a Galactic extinction-corrected magnitude of Ko≤11.75mag.
Also included are galaxies at higher latitudes in areas of high
foreground extinctions (E(B-V)>0.95). This catalogue supersedes the
previously presented bright 2MZoA catalogue which was only complete to
Ko<11.25mag. It fully complements the 2MASS Redshift Survey (2MRS)
galaxy catalogue, which has the same magnitude limit but excludes high
extinction regions. The combination of the two catalogues, the
extended 2MRS or e2MRS, is is a uniquely whole sky redshift survey and
forms a sound basis for studies of large-scale structures, flow fields
and extinction across the ZoA.
The here presented catalogue comprises 6899 galaxies with 6757
galaxies at low latitudes and 142 galaxies in highly obscured
high-latitude areas. The completion rate in redshifts is almost 75%.
The catalogue is complete up to star density levels of at least
logN*/deg2<4.3, but the completion rate of the fainter part is
affected by foreground extinction at all levels. This can be rectified
by using a diameter-dependent extinction correction, adding 1083
highly obscured but apparently faint galaxies (with Ko>11.75mag and
Ko,d≤11.75mag) to the sample. This extended sample shows good
completion rates with extinction up to at least AK<1.3mag. Omission
of such a diameter-dependent extinction correction may lead to a
biased flow field even at intermediate extinction values as found in
the 2MRS survey. As in our previous investigations, we do not find a
dependence of the correction factor f=0.86 to the extinction maps on
Galactic longitudes or latitudes, but note a possible influence by
cosmic variance.
Description:
Table A.1 lists the catalogue of objects with 2MASX parameters and
various flag settings. Table A.1a gives the full sample, and Table
A.1b lists the supplementary sample. For completion reasons we have
added in Table A.1c twelve objects that fall above the magnitude limit
when we apply no correction factor but are otherwise not found in the
above two samples.
Tables A.2, A.3 and A.4: Compilation of radial velocities from the
literature for the galaxies presented in the catalogue. Table A.2
lists optical as well as IR and X-ray measurements, and Table A.3
lists radio measurements, that is HI and, in some cases, CO-line
measurements. Table A.4 gives details of the references used.
For the velocity compilation, we searched the three data bases NED,
Hyperleda and Simbad as well as individual catalogues through the CDS.
We followed up all references we could find and which were available
through ADS. Though we concentrated on objects classified as galaxies,
we also searched systematically for object class 5 (unknown) and 6
(lower likelihood for being a galaxy) to be comprehensive. Our main
interest is in original measurements, therefore we do not list all
available compilations or searched them exhaustively. The tables give
one line per redshift and reference per object. They are ordered by
(a) error (or quality) in case of original measurements and
re-reductions (unless superseding original publication), (b) by
publication year for referenced redshifts, and (c) averaged values or
non-detection entries. Non-accepted values (for example a detection of
another galaxy nearby or a wrong measurement) are marked in the flag
column.
The decision to use a compilation or not was mainly based on its
usefulness for identifying the best radial velocity for our catalogue.
For example, many of the more recent compilations quoted in NED are
research papers on active galaxies or high energy sources which often
take the redshift from an online data base; this is of little interest
to us since we have already searched these data bases. In some cases
we quote compilations as they appear in one of the online data bases
but did not search the full catalogues for objects that may not be
listed online. Other compilations we cross-matched at CDS for all our
objects, like the CFA and 2MRS catalogues (eg, Huchra et al.,
2012ApJS..199...26H 2012ApJS..199...26H, Falco et al., 1999PASP..111..438F 1999PASP..111..438F) or IRAS galaxy
catalogues (eg, Saunders et al., 2000MNRAS.317...55S 2000MNRAS.317...55S, Lawrence et al.,
1999MNRAS.308..897L 1999MNRAS.308..897L): These are specific redshift surveys and authors
usually have selected the 'best' redshift measurement for it, leading
sometimes to additional information or comments which were helpful to
us. To avoid excessive extra listings, we decided to mark all
references quoted by Huchra et al. (2012ApJS..199...26H 2012ApJS..199...26H) with a
capital 'H' in the comment section; similarly, we use 'L' to mark all
entries in the 2M++ catalogue by Lavaux et al. 2011MNRAS.416.2840L 2011MNRAS.416.2840L. If
the original reference was mentioned by the authors, we use an arrow
in the comments column with an abbreviation of the reference; that
reference is usually listed in our table as well.
Some publications give velocities 'corrected for Galactic rotation' or
the motion of the Local Group. We usually directly quote these
velocities (with a comment and a colon in the flag) unless we could
find a corrected velocity in one of the date bases. In some cases,
objects have not very accurate positions (eg, in older publications or
for HI blind surveys) which can make cross-matching difficult. Some of
the blind HI surveys give optical counterparts (eg, HIZOA).
We use the following abbreviations in the comments: vel=velocity,
ref=reference, vres=velocity resolution, not syst = not systematically
(usually only listed when it appears in a data base (NED, Leda,
Simbad) or useful information is special cases), pr.comm = private
communication, err=error, marg=marginal, SNR=signal-to-noise ratio,
rms=root mean square, obs=observation, lw=line width, comp = component
LSB = low surface brightness galaxy;
The following units are not explicitly given in the comments:
velocity, velocity resolution and errors are in km/s; rms in mJy, flux
in Jykm/s.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablea1a.dat 199 10493 2MZOA galaxies
tablea1b.dat 199 1083 2MZOA supplementary galaxies
tablea1c.dat 199 12 f=1.0 galaxies not in tables 1a and 1b
tablea2.dat 183 8572 Optical radial velocities
tablea3.dat 198 4939 HI radial velocities
tablea4a.dat 287 554 References for the radial velocities
tablea4b.dat 157 71 References not used but found in the
searched databases
--------------------------------------------------------------------------------
See also:
J/ApJS/199/26 : The 2MASS Redshift Survey (2MRS) (Huchra+,2012)
J/MNRAS/481/1262 : 2MASS bright galaxies HI ZoA survey (Kraan-Korteweg+, 2018)
J/MNRAS/482/5167 : The 2M-ZoA galaxy catalogue (Schroeder+,2019)
J/ApJS/245/6 : The 2RMS catalog in the Zone of Avoidance (Macri+, 2019)
J/MNRAS/503/5351 : Galactic extinction at low Galactic latitudes
(Schroeder+, 2021)
Byte-by-byte Description of file: tablea1a.dat tablea1b.dat tablea1c.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- 2MASX The 2MASX J identifier
(HHMMSSss-DDMMSSs J2000 format)
18- 24 F7.3 deg GLON Galactic longitude
26- 32 F7.3 deg GLAT Galactic latitude
34- 39 F6.3 mag E(B-V) The (B-V) color excess (1)
41 I1 --- class Object class (2)
43 A1 --- foff Object offset flag (3)
45- 46 A2 --- Oflg Object flag (4)
48 A1 --- fgal Sample flag galaxy (5)
50 I1 --- fsam Sample flag full sample (6)
52 I1 --- forig Sample flag bright sample as in Paper I (6)
54 I1 --- fbr Sample flag bright sample this paper (6)
56 I1 --- fno-f Sample flag sample with
no correction factor (6)
58 I1 --- fext Sample flag extended sample this paper (6)
60 I1 --- fext-o Sample flag extended sample as in Paper I (6)
62- 63 A2 --- Disc Galaxy disc type (7)
65- 66 A2 --- 2MRS 2MRS catalogue flags (8)
68- 71 A4 --- fvo Optical velocity flag (9)
73- 76 A4 --- fvh HI velocity flag (9)
78- 81 A4 --- fvtot Total (adopted) velocity flag (9)
83 A1 --- fNIR Deep NIR image flag (10)
85- 86 A2 --- fphot Photometry flag (11)
88- 89 A2 --- fExt Extinction flag (12)
91- 96 F6.3 mag K20 2MASX isophotal K magnitude (13)
98-102 F5.2 mag H-K ?=- 2MASX isophotal colour H-K (13)
104-108 F5.2 mag J-K ?=- 2MASX isophotal colour J-K (13)
110-111 I2 --- fvc 2MASX flag: the visual verification
score of a source
113-117 F5.1 arcsec a 2MASX major diameter (twice the 2MASX
isophotal elliptical aperture semi-major
axis) (13)
119-122 F4.2 --- b/a 2MASX axis ratio of the J+H+Ks co-added
image at the 3-sigma isophote (14)
124-127 F4.2 --- stdens ?=- 2MASX stellar density (co-added logarithm
of the number of stars (K<14mag) per
sq.degree around the object)
129-135 F7.3 mag Ko Extinction-corrected K20 magnitude (15)
137-142 F6.2 mag H-Ko ?=- Extinction-corrected colour H-K (15)
144-149 F6.2 mag J-Ko ?=- Extinction-corrected colour J-K (15)
151-155 F5.2 mag AK Extinction in the K-band (15)
157-162 F6.1 arcsec ad ?=- Extinction-corrected major diameter (16)
164-169 F6.2 mag Kod ?=- Extinction-corrected 2MASX isophotal
magnitude (16)
171-175 I5 --- v(adpt) ?=- Adopted radial velocity according to the
vtot flag
177-179 I3 --- e_v(adpt) ?=- Error of adopted radial velocity
181-199 A19 --- r_v(adpt) Reference (bibliographic code) of the
adopted radial velocity (17)
--------------------------------------------------------------------------------
Note (1): As derived from the extinction maps by Planck Collaboration et al.,
2016A&A...596A.109P 2016A&A...596A.109P.
Note (2): Object class as follows:
1 = obvious galaxy
2 = galaxy
3 = probable galaxy
4 = possible galaxy
5 = unknown
6 = lower likelihood for galaxy
7 = unlikely galaxy
8 = no galaxy
9 = obviously not a galaxy
Note (3): Object offset flag as follows:
o = coordinates that are offset from the centre of the object
e = detections near the edge of an image (at an offset position from the
object centre) which were detected with properly centred coordinates on
the adjacent image
Note (4): Object flag as follows:
p = PN
p? = possible PN
q = QSO/AGN
q? = possible QSO/AGN
b = blazar
Note (5): Sample flag galaxy as follows:
g = galaxy (object classes 1-4)
p = galaxy candidates (class 5)
Note (6): Sample flags (with 1=TRUE) as:
ftot : full sample, with Ko ≤ 11.75, GN extinction correction, f=0.86;
recommended sample
forig : bright sample as in Paper I, with Ko ≤ 11.25, SFD extinction
correction, f=1.0
fbr : bright sample this paper, with Ko ≤ 11.25, GN extinction
correction, f=0.86
fno-f : sample with no correction factor applied, with Ko ≤ 11.75, GN
extinction correction, f=1.0;
fext : extended sample with diameter-dependent extinction correction
applied, with Ko,d ≤ 11.75, GN extinction correction, f=0.86
fext-o: extended sample as in Paper I, with diameter-dependent
extinction correction, with Ko,d ≤ 11.75, SFD extinction
correction, f=0.83
Note (7): Galaxy disc type as follows:
D1 = obviously visible disc and/or spiral arms
D2 = noticeable disc
D3 = possible disc
D4 = no disc noticeable
o = not possible to tell (likely due to adjacent or superimposed stars or
very high extinction)
Note (8): 2MRS flags as follows:
c = entry in the main catalogue,
e = entry in the extra catalogue (that is, outside the 2MRS selection
criteria)
cf = entry in the flg catalogue (affected by nearby stars, but not severely)
cp = entry in the flr catalogue (severely affected by nearby stars)
ca, ea = objects that have been reprocessed and are both in the rep as
well as add catalogues (in the latter case with new IDs and
photometry, not listed by us)
cr, er = objects rejected as galaxies and which can be found in the rej
catalogues
cn, en = objects that have no redshifts yet and are listed in the nocz
catalogues
For a detailed description of the 2MRS sub-catalogues
see http://tdc-www.harvard.edu/2mrs/2mrs_readme.html
Note (9): Velocity flag as follows (combinations are possible):
o = optical measurement
h = HI measurement
: = uncertain measurement
? = questionable measurement, object ID or target (in particular in HI
the large beam size may include nearby galaxies), or an uncertain
detection (often with a low signal-to-noise ratio); in case of
ambiguous HI cross-matches, both matches will have a ? with the less
likely one being rejected
g = the velocity indicates a Galactic source
[..] = non-accepted velocity (due to questionable ID or measurement);
vop and vhi only
(..) = not yet published measurements; for vtot only
Note (10): Deep NIR image flag as follows:
U = a UKIDSS image exists
V = a VISTA image exists
H = a UHS image exists
Note (11): Photometry flag as follows (combinations possible):
O = coordinates are offset (see off)
A = improved photometry exists (see 2MRS flags)
P = photometry is severely compromised (see 2MRS flags)
F = poor photometry; in addition (see 2MRS flags)
C = improved photometry exists in John Huchra's original list (see Paper I
for details)
Note (12): Extinction flag as follows:
e = likely wrong extinction value, either due to small-scale variations or
a non-removed FIR point source
e? = a possible wrong extinction value
Note (13): Measured at the K=20mag/sq.arcsec isophote
Note (14): Single-precision entries are given in cases where the 2MASX
parameter sup_ba is not determined; these values were estimated from the
axial ratios available in the different passbands,
Note (15): Extinction in the JHK bands were converted from E(B-V) using
RB=4.14, the conversion factors AJ=0.208AB, AH=0.128AB and AK=0.087AB,
and the extinction correction factor 0.86 as derived in Paper II.
Note (16): An additional diameter-dependent extinction correction has been
applied (Riad et al., 2010MNRAS.401..924R 2010MNRAS.401..924R)
Note (17): The bibliographic code is resolved in tablea4a.dat and tablea4b.dat
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- 2MASX The 2MASX J identifier (HHMMSSss-DDMMSSs
J2000 format)
18- 19 A2 --- 2MRS 2MRS flags (4)
21 A1 --- class Object class (1)
23 A1 --- foff Object offset flag (2)
25- 26 A2 --- Oflg Object flag (3)
28- 32 A5 --- f_v(opt) Optical velocity flag (5)
34- 41 A8 --- v(opt) Optical radial velocity
43- 45 A3 --- e_v(opt) Error of optical radial velocity
47- 65 A19 --- r_v(opt) Reference (bibliographic code) of the
optical radial velocity in tablea4a.dat
67-183 A117 --- Comm Comment (6)
--------------------------------------------------------------------------------
Note (1): As derived from the extinction maps by Planck Collaboration et al.,
2016A&A...596A.109P 2016A&A...596A.109P.
Note (2): Object class as follows:
1 = obvious galaxy
2 = galaxy
3 = probable galaxy
4 = possible galaxy
5 = unknown
6 = lower likelihood for galaxy
7 = unlikely galaxy
8 = no galaxy
9 = obviously not a galaxy
Note (3): Object offset flag as follows:
o = coordinates that are offset from the centre of the object
e = detections near the edge of an image (at an offset position from the
object centre) which were detected with properly centred coordinates on
the adjacent image
Note (4): 2MRS flags as follows:
c = entry in the main catalogue,
e = entry in the extra catalogue (that is, outside the 2MRS selection
criteria)
cf = entry in the flg catalogue (affected by nearby stars, but not severely)
cp = entry in the flr catalogue (severely affected by nearby stars)
ca, ea = objects that have been reprocessed and are both in the rep as
well as add catalogues (in the latter case with new IDs and
photometry, not listed by us)
cr, er = objects rejected as galaxies and which can be found in the rej
catalogues
cn, en = objects that have no redshifts yet and are listed in the nocz
catalogues
For a detailed description of the 2MRS sub-catalogues
see http://tdc-www.harvard.edu/2mrs/2mrs_readme.html
Note (5): Optical velocity flag indicates the source of the velocity as follows:
o = optical
i = IR spectrum
x = x-ray spectrum
p = photometric redshift
r = re-reduced
c = compilation
a = averaged value
m = mixed and averaged opt and HI
g = value indicates Galactic object
n = not detected
- = not found in publication
The above can be combined with the following (usually only given for
original sources o, i, x, p and r):
: = uncertain measurement
? = questionable measurement, object ID or target, or an uncertain
detection
a = absorption line measurement
e = emission line measurement
[...] = rejected velocity (due to questionable ID or measurement)
Note (6): an arrows indicates the reference of the quoted velocity (in the
quoted paper); single quotes refer to a comment in the quoted paper;
abbreviations used see Description of Tables A.2 and A.3); general
information on the paper/observing techniques see comments in Table A.4
The HIPASS/HIZOA archive can be found at
https://www.parkes.atnf.csiro.au/research/multibeam/release/
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- 2MASX The 2MASX J identifier (HHMMSSss-DDMMSSs
J2000 format)
18- 19 A2 --- 2MRS 2MRS flags (4)
21 A1 --- class Object class (1)
23 A1 --- foff Object offset flag (2)
25- 26 A2 --- Oflg Object flag (3)
28- 32 A5 --- f_v(HI) HI velocity flag (5)
34- 41 A8 --- v(HI) HI radial velocity
43- 45 A3 --- e_v(HI) Error of HI radial velocity
47- 65 A19 --- r_v(HI) Reference (bibliographic code) of the
HI radial velocity in tablea4a.dat
67-198 A132 --- Comm Comment (6)
--------------------------------------------------------------------------------
Note (1): As derived from the extinction maps by Planck Collaboration et al.,
2016A&A...596A.109P 2016A&A...596A.109P.
Note (2): Object class as follows:
1 = obvious galaxy
2 = galaxy
3 = probable galaxy
4 = possible galaxy
5 = unknown
6 = lower likelihood for galaxy
7 = unlikely galaxy
8 = no galaxy
9 = obviously not a galaxy
Note (3): Object offset flag as follows:
o = coordinates that are offset from the centre of the object
e = detections near the edge of an image (at an offset position from the
object centre) which were detected with properly centred coordinates on
the adjacent image
Note (4): Galaxy disc type as follows:
D1 = obviously visible disc and/or spiral arms
D2 = noticeable disc
D3 = possible disc
D4 = no disc noticeable
o = not possible to tell (likely due to adjacent or superimposed stars or
very high extinction)
Note (5): Radio velocity flag as follows:
h = hi
co = CO line observation
m = marginal detection (that is, needs better SNR). We define marginal
detections as having SNR ~< 3.0; possible detections are either declared
as such in the quoted paper or, in some cases, are labelled not detected
in the respective paper but judging from the presented spectrum there
seems to be a hint of a detection.
p = possible detection (that is, needs confirmation). We define marginal
detections as having SNR ~< 3.0; possible detections are either declared
as such in the quoted paper or, in some cases, are labelled not detected
in the respective paper but judging from the presented spectrum there
seems to be a hint of a detection.
r = re-reduced
c = compilation
a = averaged value
n = not detected (only listed when helpful to understand other entries for
- = not found in publication
The above can be combined with the following (usually only given for
original sources h, co, m, p and r):
: = uncertain measurement
? = questionable measurement, object ID or target
or an uncertain detection
[...] = rejected velocity (due to questionable ID or measurement)
Note (6): an arrows indicates the reference of the quoted velocity (in the
quoted paper); single quotes refer to a comment in the quoted paper;
abbreviations used see Description of Tables A.2 and A.3); general
information on the paper/observing techniques see comments in Table A.4
The HIPASS/HIZOA archive can be found at
https://www.parkes.atnf.csiro.au/research/multibeam/release/
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea4a.dat tablea4b.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- Bibcode Bibcode of reference (1)
21- 39 A19 --- Name First Author
41- 55 A15 --- Source Source of data (2)
57- 85 A29 --- Obs Observational and velocity information (3)
87-287 A201 --- Comm Comments
--------------------------------------------------------------------------------
Note (1): Sometimes more than one bibcode is used in the literature, they
are given in the comments. Token bibcodes are used for unpublished data
in the following manner: year of observations, followed by an acronym
indicating the project, an acronym indicating the telescope used, four
zeros and the initial of the PI.
Note (2): Source of data is either the observed wavelength regime or literature
Note (3): Relevant information regarding observations (eg, telescope,
observatory or instrument used) and velocity measurement (eg, velocity
resolution, precision, corrected velocity).
--------------------------------------------------------------------------------
Acknowledgements:
Anja Schroeder, anja(at)mpe.mpg.de
(End) Patricia Vannier [CDS] 03-Nov-2025