J/ApJ/849/L36 mm-wave size study of ALMA submm galaxies (Ikarashi+, 2017)
Very compact millimeter sizes for composite star-forming/AGN submillimeter
galaxies.
Ikarashi S., Caputi K.I., Ohta K., Ivison R.J., Lagos C.D.P., Bisigello L.,
Hatsukade B., Aretxaga I., Dunlop J.S., Hughes D.H., Iono D., Izumi T.,
Kashikawa N., Koyama Y., Kawabe R., Kohno K., Motohara K., Nakanishi K.,
Tamura Y., Umehata H., Wilson G.W., Yabe K., Yun M.S.
<Astrophys. J., 849, L36 (2017)>
=2017ApJ...849L..36I 2017ApJ...849L..36I
ADC_Keywords: Galaxies, photometry; Millimetric/submm sources; Redshifts;
Active gal. nuclei
Keywords: galaxies: evolution ; galaxies: formation ; galaxies: high-redshift ;
submillimeter: galaxies
Abstract:
We report the study of the far-infrared (IR) sizes of submillimeter
galaxies (SMGs) in relation to their dust-obscured star formation rate
(SFR) and active galactic nuclei (AGN) presence, determined using
mid-IR photometry. We determined the millimeter-wave
(λobs=1100um) sizes of 69 Atacama Large Millimeter/submillimeter
Array (ALMA)-identified SMGs, selected with ≥10σ confidence on
ALMA images (F1100um=1.7-7.4mJy). We found that all of the SMGs are
located above an avoidance region in the size-flux plane, as expected
by the Eddington limit for star formation. In order to understand what
drives the different millimeter-wave sizes in SMGs, we investigated
the relation between millimeter-wave size and AGN fraction for 25 of
our SMGs at z=1-3. We found that the SMGs for which the mid-IR
emission is dominated by star formation or AGN have extended
millimeter-sizes, with respective median Rc,e=1.6-0.21+0.34 and
1.5-0.24+0.93kpc. Instead, the SMGs for which the mid-IR emission
corresponds to star-forming/AGN composites have more compact
millimeter-wave sizes, with median Rc,e=1.0-0.20+0.20kpc. The
relation between millimeter-wave size and AGN fraction suggests that
this size may be related to the evolutionary stage of the SMG. The
very compact sizes for composite star-forming/AGN systems could be
explained by supermassive black holes growing rapidly during the SMG
coalescing, star-formation phase.
Description:
The sample used in this paper comes from our ALMA 1100um continuum
imaging survey of 144 bright AzTEC/ASTE sources with
F1100um,AzTEC≥2.4mJy in the Subaru/XMM-Newton Deep Field (SXDF;
Furusawa+ 2008, J/ApJS/176/1). The SXDF survey was conducted in the
ALMA Cycles 2 and 3 (2013.1.00781, 2015.1.00442.S: PI: Hatsukade;
B. Hatsukade et al. 2017, in preparation).
The typical synthesized beam size for our ALMA continuum images is
∼0.30"x0.23" (PA∼56°), after combining the Cycle 2 and 3 data. The
ALMA continuum maps yielded 70 ALMA-identified AzTEC submillimeter
galaxies (hereafter ASXDF SMGs) with Speak/N≥10 detections,
suitable for reliable ALMA millimeter-wave size measurements.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 114 70 Summary data of the ASXDF submillimeter galaxy
samples used in this paper
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See also:
J/MNRAS/380/199 : SCUBA Half-Degree Extragalactic Survey. III (Ivison+, 2007)
J/ApJ/663/81 : SED of hard X-ray selected AGN in XMDS (Polletta+, 2007)
J/ApJS/176/1 : Subaru/XMM-Newton deep survey (SXDS). II. (Furusawa+, 2008)
J/ApJS/179/124 : Subaru/XMM-Newton deep survey (SXDS) III. (Ueda+, 2008)
J/ApJ/712/942 : z>4 submillimeter galaxies (Michalowski+, 2010)
J/A+A/514/A10 : AGNs in submm-selected Lockman Hole gal. (Serjeant+, 2010)
J/ApJS/203/24 : Structural param. of galaxies in CANDELS (van der Wel+, 2012)
J/MNRAS/440/3462 : AzTEC/ASTE 1.1mm survey of SSA22 (Umehata+, 2014)
J/ApJ/788/125 : An ALMA survey of ECDFS submm galaxies (Simpson+, 2014)
J/ApJ/820/82 : S2CLS: multiwavelength counterparts to SMGs (Chen+, 2016)
J/A+A/591/A28 : 2 QSOs SINFONI K-band datacubes (Carniani+, 2016)
J/ApJ/850/83 : DANCING-ALMA. I. submm/mm continuum sources (Fujimoto+, 2017)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- --- [ASXDF]
6- 16 A11 --- ASXDF Identifier (1100.NNN.NA)
18- 20 A3 --- f_ASXDF [osd, ] Flag on ASXDF (1)
22- 22 I1 h RAh Hour of right ascension (J2000)
24- 25 I2 min RAm Minute of right ascension (J2000)
27- 31 F5.2 s RAs Second of right ascension (J2000)
33 A1 --- DE- Sign of declination (J2000)
34- 34 I1 deg DEd Degree of declination (J2000)
36- 37 I2 arcmin DEm Arcminute of declination (J2000)
39- 42 F4.1 arcsec DEs Arcsecond of declination (J2000)
44- 45 I2 --- SNR [10/25] Signal to noise ratio
47- 50 F4.2 mJy F1100 [1.1/7.5] ALMA 1100um continuum flux
52- 55 F4.2 mJy e_F1100 [0.1/0.6] F1100 uncertainty
57- 59 F3.1 --- zph [0.5/6.8]? Photometric redshift
61- 64 F4.2 --- e_zph [0/0.9]? Negative uncertainty on zph
66- 69 F4.2 --- E_zph [0/0.9]? Positive uncertainty on zph
70 A1 --- f_zph [abc] Flag on zph (1)
72- 75 I4 Msun/yr SFR [140/1500]? Star formation rate
77- 79 I3 Msun/yr e_SFR [50/510]? Negative uncertainty on SFR
81- 83 I3 Msun/yr E_SFR [110/990]? Positive uncertainty on SFR
85- 88 F4.2 arcsec FWHM [0.08/0.7] mm-wave size (FWHM)
90- 93 F4.2 arcsec e_FWHM [0.02/0.2] Negative uncertainty on FWHM
95- 98 F4.2 arcsec E_FWHM [0.02/0.1] Positive uncertainty on FWHM
100-102 F3.1 kpc Rad [0.2/2.6]? mm-wave size (circularized
effective radius (Rc,e))
104-106 F3.1 kpc e_Rad [0.1/0.4]? Negative uncertainty on Rad
108-110 F3.1 kpc E_Rad [0.1/0.5]? Positive uncertainty on Rad
112-114 A3 --- AGN mid-IR AGN diagnostic (2)
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Note (1): Flag as follows:
d = ALMA flux, SNR, and size measurements are conducted in the ALMA data after
combining the Cycle 2 and 3 data. For sources without "d", all ALMA
measurements were done in the ALMA Cycle-2 data.
s = The SMGs are not included in the analysis in Section 5 because of
non-detection in 24um.
o = The SMGs are not included in the analysis in Section 5 because of source
blending in the IRAC maps.
a = Spectroscopic redshifts by cross-identification with the UDS-z survey
catalog (e.g., Bradshaw+ 2013MNRAS.433..194B 2013MNRAS.433..194B ;
McLure+ 2013MNRAS.428.1088M 2013MNRAS.428.1088M).
b = Spectroscopic redshifts by cross-identification with the SCUBA SMGs
(Coppin+ 2010ApJ...713..503C 2010ApJ...713..503C).
c = Spectroscopic redshifts by cross-identification with the SCUBA SMGs
(Banerji+ 2011MNRAS.418.1071B 2011MNRAS.418.1071B).
Note (2): Classification as follows:
AGN = AGN-dominant (5 occurrences)
SF = Star formation dominant (5 occurrences)
COM = Composite (11 occurrences)
NO = No class (3 occurrences)
See section 5.1 for further details.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 19-Jun-2018