J/MNRAS/514/2915 Multiwavelength study of S2CLS/NEPSC2 sources (Shim+, 2022)
Multiwavelength properties of 850-µm selected sources from the North
Ecliptic Pole SCUBA-2 survey.
Shim H., Lee D., Kim Y., Scott D., Serjeant S., Ao Y., Barrufet L.,
Chapman S.C., Clements D.L., Conselice C.J., Goto T., Greve T.R.,
Hwang H.S., Im M., Jeong W.-S., Kim H.K., Kim M., Kim S.J., Kong A.K.H.,
Koprowski M.P., Malkan M.A., Micha M., Pearson C., Seo H., Takagi T.,
Toba Y., White G.J., Woo J.-H.
<Mon. Not. R. Astron. Soc. 514, 2915-2935 (2022)>
=2022MNRAS.514.2915S 2022MNRAS.514.2915S (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies ; Active gal. nuclei ; Millimetric/submm sources ;
Cross identifications ; Photometry ; Positional data ;
Energy distributions ; Models ; Radio sources ; Optical ;
Infrared sources ; Redshifts ; Star Forming Region ; Extinction ;
Stars, masses
Keywords: surveys - galaxies: evolution - galaxies: high-redshift -
galaxies: starburst - submillimetre: galaxies
Abstract:
We present the multiwavelength counterparts of 850-µm selected
submillimetre sources over a 2-deg2 field centred on the North
Ecliptic Pole. In order to overcome the large beam size (15 arcsec) of
the 850-µm images, deep optical to near-infrared (NIR) photometric
data and arcsecond-resolution 20-cm images are used to identify
counterparts of submillimetre sources. Among 647 sources, we identify
514 reliable counterparts for 449 sources (69 per cent in number),
based either on probabilities of chance associations calculated from
positional offsets or offsets combined with the optical-to-NIR
colours. In the radio imaging, the fraction of 850-µm sources
having multiple counterparts is 7 per cent. The photometric redshift,
infrared luminosity, stellar mass, star formation rate (SFR), and the
active galactic nucleus (AGN) contribution to the total infrared
luminosity of the identified counterparts are investigated through
spectral energy distribution fitting. The SMGs are infrared-luminous
galaxies at an average = 2.5 with log10(LIR/L☉) = 11.5-13.5,
with a mean stellar mass of log10(Mstar/M☉) = 10.90
and SFR of log10(SFR/M☉.yr-1)=2.34. The submillimetre
galaxies (SMGs) show twice as large SFR as galaxies on the
star-forming main sequence, and about 40 per cent of the SMGs are
classified as objects with bursty star formation. At z => 4, the
contribution of AGN luminosity to total luminosity for most SMGs is
larger than 30 per cent. The FIR-to-radio correlation coefficient of
SMGs is consistent with that of main-sequence galaxies at z ≃ 2.
Description:
The population of submillimetre galaxies SMGs has been unveiled and
widely studied during the past two decades, supporting the idea that a
significant fraction of star formation is located in heavily
dust-obscured galaxies during the peak epoch of cosmic star formation.
In order to probe the formation and evolution of SMGs, it is necessary
to identify SMGs in other wavebands. For instance, an
optical/near-infrared (NIR) identification is crucial for estimating
properties such as stellar mass and photometric redshift. The North
Ecliptic Pole NEP region is one of the seven extragalactic fields
included in the original S2CLS project. Here we focus on S2CLS-NEP
850µm sources and their counterparts from multiwavelength data sets
including the X-ray, optical, NIR, MIR, FIR and radio wavelengths. We
present these photometric and spectroscopic data located in the full
NEP survey field in order to predict their physical properties.
Firstly, we start from sub-mm merged S2CLS/NEPSC2 catalog of 644
unique 850µm sources. As exposed along the section 2, we search
counterparts in multiwavelength data sets in order to apply different
identification methods based on counterparts probability (i.e section
3). We construct the final counterparts catalogue by compiling all the
counterpart identification results as exposed in tablea1.dat
regrouping cross IDs and all positional data. Next in order to prepare
to the SED fitting work (i.e section 4), we regroup all density fluxes
of these 514 850µm counterparts from optical to radio in
tablea2.dat. We use the CIGALE algorithm to extract physical
properties of these galaxies such as photometric redshift, total IR
luminosity, SFR, stellar mass, AV, fAGN, and qFIR, as well as their
uncertainties (i.e sections 4 & 5). All these properties are then
presented in tablea2.dat with flags to indicate the SED fit quality and
reliability.
Objects:
----------------------------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------------------------
18 00 00.00 +66 33 38.5 NAME NEP = NAME North Ecliptic Pole
----------------------------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablea1.dat 203 760 Counterpart identification results for entire
644 unique 850µm sources from the
NEPSC2+S2CLS merge survey
tablea2.dat 1774 514 Multiwavelength photometry of the 514 identified
counterparts and the CIGALE outputs for each
object
--------------------------------------------------------------------------------
See also:
J/MNRAS/458/4321 : SCUBA-2 galaxies in 850um survey (Koprowski+, 2016)
J/MNRAS/436/1919 : SCUBA observations of COSMOS galaxies (Casey+, 2013)
J/MNRAS/380/199 : SCUBA Half-Degree Extragalactic Survey. III (Ivison+, 2007)
J/MNRAS/465/1789 : SCUBA-2 Cosmology Legacy Survey (Geach+, 2017)
J/MNRAS/495/3409 : SCUBA-2-COSMOS field brightest sub-mm sources
(Simpson+, 2020)
J/MNRAS/498/5065 : NEPSC2, the North Ecliptic Pole SCUBA-2 survey (Shim+, 2020)
J/MNRAS/494/3828 : ALMA survey of the SCUBA-2 CLS UDS field
(Dudzeviciute+, 2020)
J/MNRAS/469/492 : JCMT/SCUBA2 objects in COSMOS and UDS fields
(Michalowski+ 2017)
J/ApJ/886/48 : Radio & opt/NIR counterparts of S2COSMOS submm galaxies
(An+, 2019)
J/ApJ/880/43 : S2COSMOS: bright SCUBA-2 submm sources in COSMOS
(Simpson+, 2019)
J/ApJ/820/82 : S2CLS: multiwavelength counterparts to SMGs (Chen+, 2016)
J/ApJ/889/80 : STUDIES. III. SCUBA-2 450um gal. with MIPS & VLA obs.
(Lim+, 2020)
J/MNRAS/446/911 : X-ray sources in the AKARI NEP deep field (Krumpe+, 2015)
J/MNRAS/500/4078 : Band-merged catalogue of AKARI infrared sources (Kim+, 2021)
J/MNRAS/498/609 : AKARI North Ecliptic Pole field in CFHT u-band (Huang+,2020)
J/MNRAS/446/911 : X-ray sources in the AKARI NEP deep field (Krumpe+, 2015)
J/ApJS/190/166 : Optical catalog of AKARI NEP-wide survey (Jeon+, 2010)
J/ApJS/214/20 : AKARI NEP field J- and H- band source catalog (Jeon+, 2014)
J/ApJS/234/38 : Spitzer/IRAC obs. of the North Ecliptic Pole (Nayyeri+,2018)
J/A+A/645/A95 : NEP raster ROSAT X-ray/Optical catalog (Hasinger+, 2021)
J/A+A/537/A24 : AKARI NEP-Deep field mid-IR source catalogue (Takagi+, 2012)
J/A+A/517/A54 : 20cm survey of the AKARI NEP (White+, 2010)
J/A+A/548/A29 : IR source catalog of AKARI NEP-Wide field (Kim+, 2012)
J/A+A/566/A60 : Optical-NIR catalog of AKARI NEP Deep Field (Oi+, 2014)
J/PASJ/71/13 : Herschel-PACS North Ecliptic Pole Survey (Pearson+, 2019)
J/A+A/514/A10 : AGNs in submm-selected Lockman Hole galaxies
(Serjeant+, 2010)
J/A+A/622/A103 : Python Code Investigating GALaxy Emission (Boquien+, 2019)
J/ApJ/806/110 : ALESS survey: SMGs in the ECDF-S data (da Cunha+, 2015)
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- SMM ?=-32768 The SMM identifier in the combined
catalogue (SMM_ID)
7- 27 A21 --- NEPSC2 The NEPSC2 identifier (NEPSC2_ID) (1)
29- 36 A8 --- S2CLS The S2CLS identifier (S2CLS_ID) (2)
38- 46 A9 --- Radio The radio counterpart identifier (radio_id)
(3)
48- 55 A8 --- OptIR The Optical-Infrared identifier (optir_id)
(4)
57- 68 F12.8 deg RA850deg Right ascension of the 850 µm source
(J2000) (RA_850um)
70- 80 F11.8 deg DE850deg Declination of the 850 µm source (J2000)
(Dec_850um)
82- 94 F13.9 deg RAVLAdeg ? Right ascension of the counterpart in the
VLA images (J2000) (RA_VLA)
96-107 F12.9 deg DEVLAdeg ? Declination of the counterpart in the VLA
images (J2000) (Dec_VLA)
109-120 F12.8 deg RAIRACdeg ? Right ascension of the counterpart in IRAC
images (J2000) (RA_IRAC)
122-133 F12.9 deg DEIRACdeg ? Declination of the counterpart in IRAC
images (J2000) (Dec_IRAC)
135-147 F13.9 deg RAoptdeg ? Right ascension of the counterpart in HSC
images (J2000) (RA_opt) (5)
149-160 F12.9 deg DEoptdeg ? Declination of the counterpart in HSC
images (J2000) (Dec_opt) (5)
162-178 F17.14 mJy S850 Flux density in 850 µm S2CLS/NEPSC2
images (S_850um)
180-195 F16.14 mJy e_S850 Mean error of S850um (Serr850um)
197 I1 --- f_Radio [0/1] Flag indicates if counterpart is
identified in radio 20cm, 0 for no with 620
cases and 1 for yes with 140 cases (radioid)
199 I1 --- f_OptIR [0/1] Flag indicates if counterpart is
identified using optical-NIR colour, 0 for
no with 37 cases and 1 for yes with 723
cases (colourid)
201 I1 --- Reliable [0/1] Flag indicates if the identification
based on colour is reliable enough, 0 for no
with 300 cases and 1 for yes with 460 cases
(reliable) (6)
203 I1 --- f_SMM [0/1] Flag indicates if the submillimetre
source has more than one counterpart, 0 for
no with 538 cases and 1 for yes with 222
cases (multipleID)
--------------------------------------------------------------------------------
Note (1): North Ecliptic Pole SCUBA-2 survey source catalogue from
Shim et al. 2020MNRAS.498.5065S 2020MNRAS.498.5065S, Cat. J/MNRAS/498/5065.
Note (2): The S2CLS project SCUBA-2 Cosmology Legacy Survey from
Geach et al. 2017MNRAS.465.1789G 2017MNRAS.465.1789G, Cat. J/MNRAS/465/1789.
Note (3): As presented in the section 3.1 Radio identification, suffices 'a' and
'b' in order of positional offsets between the 850 µm and 20-cm
position.
As explained in section 2.2.1 Radio, the 20-cm continuum data (i.e.
with an effective frequency of 1525 MHz) of the NEP-deep field have
been obtained using the Karl G. Jansky Very Large Array (VLA) during
2013-2014 (project ID: VLA/13B-361 and VLA/14A-469, PI: K. Nakanishi).
Note (4): As presented in the section 3.2 Optical-to-NIR colour identification,
the identifier with '-1' and '-2' stand for primary and secondary
counterpart from the optical-NIR colour identification. IDs with '-3'
indicates that the object is not originally identified from the
optical-NIR colour identification, because of the low relative
possibility of being a match pi value. If there is more than one
number in the suffices, e.g. '-21' and '-22', it means that more than
one secondary counterpart is identified because of the definition of
the secondary identification.
Note (5): As explained in the section 2.2.3 Optical, the most recent optical
source catalogue over the entire 4 deg2 of the NEP-wide survey area
provides deep 5-band Subaru/HSC photometry in the g, r, i, z, and
y bands, respectively (Oi et al. 2021MNRAS.500.5024O 2021MNRAS.500.5024O).
Most of time when it is available, coordinates of the counterparts
are in the HSC g-band or in z/y-bands images when the object is
undetected in the g band.
Note (6): We apply a false rate cut of 10 per cent (i.e. pany > 0.74) to
define the identification as reliable. The pany i defined as the
probability of a source in a poor resolution image (850µm source
in this case) has any counterpart within the specified radius (i.e
see section 3.2 and equation 2).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- SMM ?=-32768 The SMM identifier in the
combined catalogue (SMM_ID)
7- 15 A9 --- Radio The radio counterpart identifier
(radio_id)
17- 24 A8 --- OptIR The Optical-Infrared identifier
(optir_id)
26- 46 F21.15 mJy HSCg ?=-9999 Subaru/HSC g-band flux
density (HSC_g)
48- 68 F21.15 mJy e_HSCg ?=-9999 Mean uncertainty of HSCg
(HSCgerr)
70- 90 F21.15 mJy HSCr ?=-9999 Subaru/HSC r-band flux
density (HSC_r)
92- 112 F21.15 mJy e_HSCr ?=-9999 Mean uncertainty of HSCr
(HSCrerr)
114- 134 F21.15 mJy HSCi ?=-9999 Subaru/HSC i-band flux
density (HSC_i)
136- 156 F21.15 mJy e_HSCi ?=-9999 Mean uncertainty of HSCi
(HSCierr)
158- 178 F21.15 mJy HSCz ?=-9999 Subaru/HSC z-band flux
density (HSC_z)
180- 200 F21.15 mJy e_HSCz ?=-9999 Mean uncertainty of HSCz
(HSCzerr)
202- 222 F21.15 mJy HSCy ?=-9999 Subaru/HSC y-band flux
density (HSC_y)
224- 244 F21.15 mJy e_HSCy ?=-9999 Mean uncertainty of HSCy
(HSCyerr)
246- 266 F21.15 mJy MCamu ?=-9999 CFHT/MegaCam u-band flux
density (MCam_u)
268- 288 F21.15 mJy e_MCamu ?=-9999 Mean uncertainty of MCamu
(MCamuerr)
290- 310 F21.15 mJy MCamg ?=-9999 CFHT/MegaCam g-band flux
density (MCam_g)
312- 332 F21.15 mJy e_MCamg ?=-9999 Mean uncertainty of MCamg
(MCamgerr)
334- 354 F21.15 mJy MCamr ?=-9999 CFHT/MegaCam r-band flux
density (MCam_r)
356- 376 F21.15 mJy e_MCamr ?=-9999 Mean uncertainty of MCamr
(MCamrerr)
378- 398 F21.15 mJy MCami ?=-9999 CFHT/MegaCam i-band flux
density (MCam_i)
400- 420 F21.15 mJy e_MCami ?=-9999 Mean uncertainty of MCami
(MCamierr)
422- 442 F21.15 mJy MCamz ?=-9999 CFHT/MegaCam z-band flux
density (MCam_z)
444- 464 F21.15 mJy e_MCamz ?=-9999 Mean uncertainty of MCamz
(MCamzerr)
466- 486 F21.15 mJy WFCAMY ?=-9999 Wide Field Infrared Camera
WIRCAM Y-band flux density (WFCAM_Y)
488- 508 F21.15 mJy e_WFCAMY ?=-9999 Mean uncertainty of WFCAMY
(WFCAMYerr)
510- 530 F21.15 mJy CFHT-WFCAMJ ?=-9999 CFHT/WIRCam J-band flux
density (CFHTwircamJ)
532- 552 F21.15 mJy e_CFHT-WFCAMJ ?=-9999 Mean uncertainty of
CFHT-WFCAMJ (CFHTwircamJ_err)
554- 574 F21.15 mJy CFHT-WFCAMKs ?=-9999 CFHT/WIRCam Ks-band flux
density (CFHTwircamKs)
576- 596 F21.15 mJy e_CFHT-WFCAMKs ?=-9999 Mean uncertainty of
CFHT-WFCAMKs (CFHTwircamKs_err)
598- 618 F21.15 mJy IRAC3.6 ?=-9999 Spitzer/IRAC 3.6µm-band
flux density (IRAC1)
620- 640 F21.15 mJy e_IRAC3.6 ?=-9999 Mean uncertainty of IRAC3.6
(IRAC1_err)
642- 662 F21.15 mJy IRAC4.5 ?=-9999 Spitzer/IRAC 4.5µm-band
flux density (IRAC2)
664- 684 F21.15 mJy e_IRAC4.5 ?=-9999 Mean uncertainty of IRAC4.5
(IRAC2_err)
686- 706 F21.15 mJy N2 ?=-9999 AKARI/IRC NEP-deep/wide
surveys N2-band 2.4µm flux density
(N2-band)
708- 728 F21.15 mJy e_N2 ?=-9999 Mean uncertainty of N2
(N2_err)
730- 750 F21.15 mJy N3 ?=-9999 AKARI/IRC NEP-deep/wide
surveys N3-band 3.2µm flux density
(N3-band)
752- 772 F21.15 mJy e_N3 ?=-9999 Mean uncertainty of N3
(N3_err)
774- 794 F21.15 mJy N4 ?=-9999 AKARI/IRC NEP-deep/wide
surveys N4-band 4.1µm flux density
(N4-band)
796- 816 F21.15 mJy e_N4 ?=-9999 Mean uncertainty of N4
(N4_err)
818- 838 F21.15 mJy S7 ?=-9999 AKARI/IRC NEP-deep/wide
surveys S7-band 7.0µm flux density
(S7)
840- 860 F21.15 mJy e_S7 ?=-9999 Mean uncertainty of S7
(S7_err)
862- 882 F21.15 mJy S9W ?=-9999 AKARI/IRC NEP-deep/wide
surveys S9W-band 9.0µm flux
density (S9W)
884- 904 F21.15 mJy e_S9W ?=-9999 Mean uncertainty of S9W
(S9W_err)
906- 926 F21.15 mJy S11 ?=-9999 AKARI/IRC NEP-deep/wide
surveys S11-band 11.0µm flux
density (S11)
928- 948 F21.15 mJy e_S11 ?=-9999 Mean uncertainty of S11
(S11_err)
950- 970 F21.15 mJy L15 ?=-9999 AKARI/IRC NEP-deep/wide
surveys L15-band 15µm flux density
(L15)
972- 992 F21.15 mJy e_L15 ?=-9999 Mean uncertainty of L15
(L15_err)
994-1014 F21.15 mJy L18W ?=-9999 AKARI/IRC NEP-deep/wide
surveys L18-band 18µm flux density
(L18W)
1016-1036 F21.15 mJy e_L18W ?=-9999 Mean uncertainty of L18W
(L18W_err)
1038-1058 F21.15 mJy L24 ?=-9999 AKARI/IRC NEP-deep/wide
surveys L24-band 24µm flux density
(L24)
1060-1080 F21.15 mJy e_L24 ?=-9999 Mean uncertainty of L24
(L24_err)
1082-1097 F16.10 mJy MIPS24 ?=-9999 Spitzer/MIPS 24µm band
flux density (MIPS1)
1099-1113 F15.9 mJy e_MIPS24 ?=-9999 Mean uncertainty of MIPS24
(MIPS1_err)
1115-1135 F21.15 mJy WISE3.4 ?=-9999 Wide-field Infrared Survey
Explorer WISE-band 3.4µm flux
density (WISE1)
1137-1157 F21.15 mJy e_WISE3.4 ?=-9999 Mean uncertainty of WISE3.4
(WISE1_err)
1159-1179 F21.15 mJy WISE4.6 ?=-9999 Wide-field Infrared Survey
Explorer WISE-band 4.6µm flux
density (WISE2)
1181-1201 F21.15 mJy e_WISE4.6 ?=-9999 Mean uncertainty of WISE4.6
(WISE2_err)
1203-1223 F21.15 mJy WISE12 ?=-9999 Wide-field Infrared Survey
Explorer WISE-band 12µm flux
density (WISE3)
1225-1245 F21.15 mJy e_WISE12 ?=-9999 Mean uncertainty of WISE12
(WISE3_err)
1247-1267 F21.15 mJy WISE22 ?=-9999 Wide-field Infrared Survey
Explorer WISE-band 22µm flux
density (WISE4)
1269-1289 F21.15 mJy e_WISE22 ?=-9999 Mean uncertainty of WISE22
(WISE4_err)
1291-1306 F16.10 mJy PACS100 ?=-9999 The Herschel/PACS green
100µm band flux density
(PACS_green)
1308-1328 F21.15 mJy e_PACS100 ?=-9999 Mean uncertainty of PACS100
(PACSgreenerr)
1330-1343 F14.8 mJy PACS160 ?=-9999 The Herschel/PACS red
160µm band flux density (PACS_red)
1345-1364 F20.14 mJy e_PACS160 ?=-9999 Mean uncertainty of PACS160
(PACSrederr)
1366-1379 F14.8 mJy SPIRE250 ?=-9999 The Herschel/SPIRE 250µm
band flux density (PSW)
1381-1401 F21.15 mJy e_SPIRE250 ?=-9999 Mean uncertainty of SPIRE250
(PSW_err)
1403-1415 F13.7 mJy SPIRE350 ?=-9999 The Herschel/SPIRE 350µm
band flux density (PMW)
1417-1437 F21.15 mJy e_SPIRE350 ?=-9999 Mean uncertainty of SPIRE350
(PMW_err)
1439-1452 F14.8 mJy SPIRE500 ?=-9999 The Herschel/SPIRE 500µm
band flux density (PLW)
1454-1473 F20.14 mJy e_SPIRE500 ?=-9999 Mean uncertainty of SPIRE500
(PLW_err)
1475-1494 F20.14 mJy SCUBA850 SCUBA-2 surveys 850µm band flux
density (SCUBA850)
1496-1515 F20.14 mJy e_SCUBA850 Mean uncertainty of SCUBA850
(SCUBA850_err)
1517-1530 F14.8 mJy VLAL20 ?=-9999 Radio VLA L-band 20cm flux
density (VLA_L)
1532-1552 F21.15 mJy e_VLAL20 ?=-9999 Mean uncertainty of VLAL20
(VLALerr)
1554 I1 --- SEDok [0/1] Flag indicates if the CIGALE
SED fit is a good quality, 0 for no
with 180 cases and 1 for yes with 334
cases (ok_sedfit)
1556 I1 --- f_z [0/1] Flag to indicates if the
redshift is spectroscopic, 0 for
photometric with 496 cases and 1 for
yes with 18 cases (ifspecz)
1558-1574 F17.15 --- z Redshift from CIGALE output results
(redshift)
1576-1593 F18.15 --- e_z ?=-1 Mean uncertainty of z
(redshift_err)
1595-1605 E11.5 W LIR Total fitting IR luminosity from
CIGALE output results (LIR)
1607-1617 E11.5 W e_LIR Mean uncertainty of LIR (LIR_err)
1619-1638 F20.15 Msun/yr SFR Star forming rate SFR from CIGALE
output results (SFR)
1640-1659 F20.15 Msun/yr e_SFR Mean uncertainty of SFR (SFR_err)
1661-1671 E11.5 Msun M* Stellar mass from CIGALE output
results (Mstar)
1673-1683 E11.5 Msun e_M* Mean uncertainty of M* (Mstar_err)
1685-1701 F17.15 mag Av Extinction coefficient from CIGALE
output results (Av)
1703-1713 E11.5 mag e_Av Mean uncertainty of Av (Av_err)
1715-1726 E12.6 --- fAGN AGN fraction luminosity defined as
LAGN/(LAGN + LSF) from CIGALE
output results (fracAGN)
1728-1739 F12.6 --- e_fAGN Mean uncertainty of fAGN (fracAGN_err)
1741-1756 F16.14 --- qfir ? FIR-to-radio correlation
coefficient from CIGALE output
results (radio_qfir)
1758-1774 F17.15 --- e_qfir ? Mean uncertainty of qfir
(radioqfirerr)
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History:
From electronic version of the journal
(End) Luc Trabelsi [CDS] 07-Apr-2025