J/ApJ/919/51 HST F160W obs. of the SSA22 protocluster field (Monson+, 2021)
On the nature of AGN and star formation enhancement in the z=3.1 SSA22
protocluster: the HST WFC3 IR view.
Monson E.B., Lehmer B.D., Doore K., Eufrasio R.T., Bonine B.,
Alexander D.M., Harrison C.M., Kubo M., Mantha K.B., Saez C., Straughn A.,
Umehata H.
<Astrophys. J., 919, 51 (2021)>
=2021ApJ...919...51M 2021ApJ...919...51M
ADC_Keywords: Clusters, galaxy; Redshifts; Photometry, HST; Active gal. nuclei;
Photometry, infrared; Photometry, UBVRI; Morphology
Keywords: High-redshift galaxy clusters ; High-redshift galaxies ;
Active galactic nuclei ; X-ray active galactic nuclei ; Galaxy mergers
Abstract:
We examine possible environmental sources of the enhanced star
formation and active galactic nucleus (AGN) activity in the z=3.09
SSA22 protocluster using Hubble WFC3 F160W (∼1.6µm) observations of
the SSA22 field, including new observations centered on eight X-ray
selected protocluster AGN. To investigate the role of mergers in the
observed AGN and star formation enhancement, we apply both
quantitative (Sersic-fit and Gini-M20) and visual morphological
classifications to F160W images of protocluster Lyman-break galaxies
(LBGs) in the fields of the X-ray AGN and z∼3 field LBGs in SSA22 and
GOODS-N. We find no statistically significant differences between the
morphologies and merger fractions of protocluster and field LBGs,
though we are limited by small number statistics in the protocluster.
We also fit the UV-to-near-IR spectral energy distributions of
F160W-detected protocluster and field LBGs to characterize their
stellar masses and star formation histories. We find that the mean
protocluster LBG is a factor of ∼2 times more massive and more
attenuated than the mean z∼3 field LBG. We take our results to suggest
that ongoing mergers are not more common among protocluster LBGs than
field LBGs, though protocluster LBGs appear to be more massive. We
speculate that the larger mass of the protocluster LBGs contributes to
the enhancement of SMBH mass and accretion rate in the protocluster,
which in turn drives the observed protocluster AGN enhancement.
Description:
We use 16 HST WFC3 F160W images of the SSA22 field for our
morphological analyses (HST proposals 13844, 11735, 11636, 14747).
Six of these fields (HST proposal 13844) were new observations
obtained to cover the eight protocluster AGN detected in Chandra
observations by Lehmer+ (2009ApJ...691..687L 2009ApJ...691..687L) that were studied by
Alexander+ (2016MNRAS.461.2944A 2016MNRAS.461.2944A).
We adopt a cosmology with H0=70km/s/Mpc, ΩM=0.3, and
ΩΛ=0.7, yielding a lookback time of 11.42Gyr, a 2.04Gyr
universe age, and a physical scale of 7.63 proper kpc/arcsec at z=3.09.
We define SSA22 protocluster galaxies as those galaxies in our F160W
images with 3.06≤z≤3.12. Over this range of redshift, the rest-frame
wavelength probed by our WFC3 IR observations ranges from 3740 to 3790Å.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
22 17 34.00 +00 17 00.9 SSA22 = NAME SSA22 Protocluster
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 560 7538 *Catalog showing the GALFITM-extracted
morphological parameters (see Section 3.1)
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Note on table2.dat: We use GALAPAGOS-2 (Barden+ 2012MNRAS.422..449B 2012MNRAS.422..449B and
Haussler+ 2013MNRAS.430..330H 2013MNRAS.430..330H) to carry out source detection (using
SExtractor), background determination, model fitting (using GALFITM,
an updated multiband version of GALFIT; see Vika+ 2013MNRAS.435..623V 2013MNRAS.435..623V),
and catalog compilation. See Section 2.2.
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See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
J/ApJ/588/218 : i*g* photometry of SDSS EDR galaxies (Abraham+, 2003)
J/AJ/126/1183 : Major galaxy mergers at z≲3 (Conselice+, 2003)
J/ApJ/592/728 : Lyman break galaxies at redshift z∼3 (Steidel+, 2003)
J/AJ/128/163 : Galaxy morphological classification (Lotz+, 2004)
J/ApJS/172/615 : GALFIT result for GEMS galaxies (Haussler+, 2007)
J/MNRAS/400/299 : Chandra deep protocluster survey (Lehmer+, 2009)
J/ApJ/730/125 : HST/NICMOS obs. of bright IR galaxies (Zamojski+, 2011)
J/ApJS/203/24 : Structural param. of CANDELS galaxies (van der Wel+, 2012)
J/A+A/559/A14 : VIMOS VLT Deep Survey final data release (Le Fevre+, 2013)
J/ApJ/765/87 : Chandra obs. of the 2QZ Cluster 1004+00 (Lehmer+, 2013)
J/MNRAS/435/623 : Multiwavelength measurement of galaxy structure (Vika, 2013)
J/MNRAS/440/3462 : AzTEC/ASTE 1.1mm survey of SSA22 (Umehata+, 2014)
J/MNRAS/450/2615 : Spectroscopy of galaxies in the SSA22 field (Saez+, 2015)
J/MNRAS/460/3861 : Herschel protocluster survey (Kato+, 2016)
J/ApJ/826/114 : z∼3-6 protoclusters in CFHTLS deep fields (Toshikawa+, 2016)
J/MNRAS/465/316 : Lyman cont. LAEs and LBGs in SSA22 field (Micheva+, 2017)
J/MNRAS/480/1022 : Black-hole growth and cosmic environment (Yang+, 2018)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- ID Identifier (JHHMMSS.ss+DDMMSS.s)
21- 28 A8 --- GALAP Internal GALAPAGOS identifier
30- 45 A16 --- SAS-LBG Steidel+ 2003, J/ApJ/592/728 (S03) ID
47- 55 F9.5 deg RAdeg [334.18/334.52] Right Ascension (J2000)
57- 63 F7.5 deg DEdeg [0.16/0.4] Declination (J2000)
65- 70 F6.1 --- SN [5/3856] F160W signal to noise ratio in a
1" aperture
72 I1 --- Fit [0/1] Fit flag (1=unacceptable GALFITM
Sersic fit) (1)
74- 80 F7.3 mag F160Wmag [16.8/29.8]?=-99 Integrated Sersic model
F160W AB magnitude
82- 88 F7.3 mag e_F160Wmag [0/1.6]?=-99 Uncertainty in F160Wmag
90- 96 F7.3 arcsec Re [0.02/24.2]?=-99 Sersic model effective
radius
98- 104 F7.3 arcsec e_Re [0/18]?=-99 Uncertainty in Re
106- 112 F7.3 --- n [0.2/9.7]?=-99 Sersic model index
114- 120 F7.3 --- e_n [0/8.9]?=-99 Uncertainty in n
122- 128 F7.3 --- q [0.1/1]?=-99 Sersic model axis ratio; b/a
130- 136 F7.3 --- e_q [0/11]?=-99 Uncertainty in q
138- 144 F7.3 deg PA [-90/90]?=-99 Sersic model position
angle (east of north)
146- 155 F10.3 deg e_PA [0/879023]?=-99 Uncertainty in PosAng
157- 163 F7.3 --- z [0/10]?=-99 Literature spectroscopic
redshift
165 I1 --- r_z [0/9] Reference flag for z (2)
167- 173 F7.3 --- zS03abs [0/3.3]?=-99 S03 absorption-line redshift
175- 181 F7.3 --- zS03em [0/3.4]?=-99 S03 emission-line redshift
183- 189 F7.3 --- zM17 [3/3.8]?=-99 Micheva+ 2017,
J/MNRAS/465/316 (M17) spectroscopic
redshift
191- 197 F7.3 --- zS15 [0.2/3.4]?=-99 Spectroscopic redshift from
Saez+ 2015, J/MNRAS/450/2615 (S15)
199- 205 F7.3 --- zY12 [3/3.2]?=-99 Yamada+ 2012AJ....143...79Y 2012AJ....143...79Y
(Y12) spectroscopic redshift
207- 213 F7.3 --- zVVDS [0/10]?=-99 VVDS (Le Fevre+ 2013,
J/A+A/559/A14) spectroscopic redshift
215- 221 F7.3 --- zK15 [3/3.5]?=-99 Kubo+ 2015ApJ...799...38K 2015ApJ...799...38K
(K15) spectroscopic redshift
223- 229 F7.3 mag umag [15.8/33.7]?=-99 MegaCam/CFHT u*-band
aperture AB magnitude (3)
231- 237 F7.3 mag e_umag [0/7]?=-99 Uncertainty in umag
239- 245 F7.3 mag Bmag [17.4/33]?=-99 Subaru/Suprime-Cam B-band
aperture AB magnitude (3)
247- 253 F7.3 mag e_Bmag [0/6]?=-99 Uncertainty in Bmag
255- 261 F7.3 mag Vmag [17.5/31.5]?=-99 Subaru/Suprime-Cam V-band
aperture AB magnitude (3)
263- 269 F7.3 mag e_Vmag [0/4]?=-99 Uncertainty in Vmag
271- 277 F7.3 mag Rmag [18.2/30]?=-99 Subaru/Suprime-Cam R-band
aperture AB magnitude (3)
279- 285 F7.3 mag e_Rmag [0/3]?=-99 Uncertainty in Rmag
287- 293 F7.3 mag imag [17.6/29]?=-99 Subaru/Suprime-Cam i'-band
aperture AB magnitude (3)
295- 301 F7.3 mag e_imag [0/2]?=-99 Uncertainty in imag
303- 309 F7.3 mag zmag [16.7/35]?=-99 Subaru/Suprime-Cam z'-band
aperture AB magnitude (3)
311- 317 F7.3 mag e_zmag [0/9]?=-99 Uncertainty in zmag
319- 325 F7.3 mag Jmag [16.6/29.6]?=-99 Subaru/MOIRCS J-band
aperture AB magnitude (3)
327- 333 F7.3 mag e_Jmag [0.001/5.1]?=-99 Uncertainty in Jmag
335- 341 F7.3 mag F160WmagK [14.8/35.2]?=-99 F160W-band aperture AB
magnitude using Kubo+ 2013ApJ...778..170K 2013ApJ...778..170K
procedures
343- 349 F7.3 mag e_F160WmagK [0/597]?=-99 Uncertainty in F160WmagK
351- 357 F7.3 mag Kmag [16.8/28]?=-99 Subaru/MOIRCS K-band
aperture AB magnitude (3)
359- 365 F7.3 mag e_Kmag [0.001/3.3]?=-99 Uncertainty in Kmag
367- 373 F7.3 mag I1mag [13.9/28.1]?=-99 Spitzer/IRAC 3.6um
aperture AB magnitude (3)
375- 381 F7.3 mag e_I1mag [0.002/4]?=-99 Uncertainty in I1mag
383- 389 F7.3 mag I2mag [14.2/29.1]?=-99 Spitzer/IRAC 4.5um
aperture AB magnitude (3)
391- 397 F7.3 mag e_I2mag [0.002/5.1]?=-99 Uncertainty in I2mag
399- 405 F7.3 mag I3mag [14.5/30.4]?=-99 Spitzer/IRAC 5.8um
aperture AB magnitude (3)
407- 413 F7.3 mag e_I3mag [0.003/8]?=-99 Uncertainty in I3mag
415- 421 F7.3 mag I4mag [15.3/29.2]?=-99 Spitzer/IRAC 8.0um
aperture AB magnitude (3)
423- 429 F7.3 mag e_I4mag [0.004/8]?=-99 Uncertainty in I4mag
431- 437 F7.3 [10-7W] logLx [40.8/44.8]?=-99 Lehmer+ 2009,
J/MNRAS/400/299 (L09) log10 2-8keV
luminosity
439- 445 F7.3 mag NB497mag [22/25.4]?=-99 Yamada+ 2012AJ....143...79Y 2012AJ....143...79Y
narrowband 4972A filter AB magnitude
447- 453 F7.3 mag RmagM17 [23.5/27]?=-99 R-band AB magnitude from
Micheva+ 2017, J/MNRAS/465/316
455- 461 F7.3 mag RmagS03 [20.8/25.5]?=-99 R-band AB magnitude from
Steidel+ 2003, J/ApJ/592/728
463- 469 F7.3 --- Conc [0.04/4.4]?=-99 F160W concentration
statistic (4)
471 I1 --- f_Conc [0/1] Flag on Conc (5)
473- 479 F7.3 --- Gini [0/0.94]?=-99 Gini coefficient (6)
481- 487 F7.3 --- M20 [-2.3/-0.35]?=-99 M20 moment-of-light (6)
489 I1 --- Flag [0/1] Flag on GINI and M20 (5)
491- 495 F5.3 arcsec-2 Dens [0.12/1.5] Local surface density of
protocluster candidate LAEs (7)
497 I1 --- S03-LBG [0/1] S03 LBG match flag (8)
499 I1 --- S03-QSO [0/1] S03 QSO match flag (8)
501 I1 --- L09-Xray [0/1] L09 X-ray match flag (8)
503 I1 --- Y12-LAE [0/1] Y12 LAE match flag (8)
505 I1 --- M17-LBG [0/1] M17 LBG match flag (8)
507 I1 --- M17-LAE [0/1] M17 LAE match flag (8)
509 I1 --- M17-LYC [0/1] M17 Lyman continuum (LYC) match
flag (8)
511 I1 --- XAGN [1/8]?=0 Alexander+ 2016MNRAS.461.2944A 2016MNRAS.461.2944A
X-ray AGN number
513- 514 I2 --- LAB [2/14]?=0 Matsuda+ 2004AJ....128..569M 2004AJ....128..569M LAB
number (<[MYH2004] LAB NN> in Simbad)
516 I1 --- Mm [0/1] Source has 3.06≤z≤3.12 flag
(1=protocluster galaxies; 72 occurrences)
518 I1 --- Field [0/1] Source has 2.9≤z≤3.3 but outside
protocluster z range (8)
520 I1 --- SED [0/1] Fit the SED of the source (8)
522- 523 A2 --- MorphA Voter A visual morphology (9)
525 I1 --- ScA [0/5] Voter A's confidence score (10)
527- 528 A2 --- MorphB Voter B visual morphology (9)
530 I1 --- ScB [0/5] Voter B's confidence score (10)
532- 533 A2 --- MorphC Voter C visual morphology (9)
535 I1 --- ScC [0/5] Voter C's confidence score (10)
537- 538 A2 --- MorphD Voter D visual morphology (9)
540 I1 --- ScD [0/5] Voter D's confidence score (10)
542- 543 A2 --- MorphE Voter E visual morphology (9)
545 I1 --- ScE [0/5] Voter E's confidence score (10)
547- 548 A2 --- MorphF Voter F visual morphology (9)
550 I1 --- ScF [0/5] Voter F's confidence score (10)
552- 553 A2 --- MorphG Voter G visual morphology (9)
555 I1 --- ScG [0/5] Voter G's confidence score (10)
557 I1 --- Class [0/3]? Final classification (11)
559- 560 A2 --- Conf Confidence-weighted visual morphology
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Note (1): 1 if the GALFITM Sersic fit was unacceptable, 0 otherwise.
Note (2): Reference as follows:
1 = Steidel+ 2003, J/ApJ/592/728 absorption-line;
2 = Steidel+ 2003, J/ApJ/592/728 emission-line;
3 = From Micheva+ 2017, J/MNRAS/465/316 Lyman-continuum emitter catalog;
4 = From Micheva+ 2017, J/MNRAS/465/316 LBG and LAE catalog;
5 = From Saez+ 2015, J/MNRAS/450/2615 X-ray source catalog;
6 = From Saez+ 2015, J/MNRAS/450/2615 non-X-ray source catalog;
7 = Yamada+ 2012AJ....143...79Y 2012AJ....143...79Y LAE catalog;
8 = VLT-VIMOS Deep Survey (VVDS; Le Fevre+ 2013, J/A+A/559/A14)
9 = Kubo+ 2015ApJ...799...38K 2015ApJ...799...38K
Note (3): From Kubo+ (2013ApJ...778..170K 2013ApJ...778..170K). u* to K-band images
were smoothed to a 1" PSF FWHM and fluxes were extracted in a 2"
diameter aperture. The IRAC band fluxes were matched to the remaining
bands by aperture corrections.
Note (4): see, e.g., Lotz+ 2004, J/AJ/128/163
Note (5): 1 if there was a problem with the measurement, 0 otherwise.
Note (6): According to Lotz+ 2004, J/AJ/128/163 algorithm.
Note (7): Candidate LAEs from Hayshino+ 2004AJ....128.2073H 2004AJ....128.2073H
Local density estimated with a Gaussian KDE.
Note (8): 1 if the source is matched, 0 otherwise.
Note (9): Using visual morphology categories from Hine+ 2016MNRAS.455.2363H 2016MNRAS.455.2363H who
defines six categories as follows:
C1 = Compact, isolated system, single nucleus.
C2 = Compact but with minor asymmetry and no clear evidence of
a second nucleus.
M1 = Evidence of two nuclei within 1" diameter aperture (∼8kpc
in projection) centred on the brightest part of the LBG.
All flux falling within the aperture.
M2 = Evidence of two nuclei within the 1" aperture, but with some
flux falling outside.
M3 = Evidence of >2 nuclei or complex clumpy structure falling within the
aperture, but with some flux falling outside.
M4 = Evidence of >2 nuclei or complex clumpy structure with all flux
falling inside the 1" diameter aperture.
Those classified as "C" are non-mergers, whilst those classified as
"M" are mergers.
Note (10): From 1 (low) to 5 (high).
Note (11): Based on voter morphologies and confidence scores. Code as follows:
0 = not classified (7495 occurrences)
1 = isolated (26 occurrences)
2 = merger (12 occurrences)
3 = ambiguous (5 occurrences)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Jan-2023