J/ApJ/889/189 Brightest high-z galaxies in RELICS clusters (Salmon+, 2020)
RELICS: The Reionization Lensing Cluster Survey and the brightest high-z
galaxies.
Salmon B., Coe D., Bradley L., Bouwens R., Bradac M., Huang K.-H.,
Oesch P.A., Stark D., Sharon K., Trenti M., Avila R.J., Ogaz S.,
Andrade-Santos F., Carrasco D., Cerny C., Dawson W., Frye B.L., Hoag A.,
Johnson T.L., Jones C., Lam D., Lovisari L., Mainali R., Past M.,
Paterno-Mahler R., Peterson A., Riess A.G., Rodney S.A., Ryan R.E.,
Sendra-Server I., Strait V., Strolger L.-G., Umetsu K., Vulcani B.,
Zitrin A.
<Astrophys. J., 889, 189 (2020)>
=2020ApJ...889..189S 2020ApJ...889..189S
ADC_Keywords: Clusters, galaxy; Galaxies, IR; Photometry, HST; Redshifts;
Surveys; Optical
Keywords: Galaxies ; galaxies: high-redshift
Abstract:
Massive foreground galaxy clusters magnify and distort the light of
objects behind them, permitting a view into both the extremely distant
and intrinsically faint galaxy populations. We present here the z∼6-8
candidate high-redshift galaxies from the Reionization Lensing Cluster
Survey (RELICS), a Hubble and Spitzer Space Telescope survey of 41
massive galaxy clusters spanning an area of ∼200arcmin2. These
clusters were selected to be excellent lenses, and we find similar
high-redshift sample sizes and magnitude distributions as the Cluster
Lensing And Supernova survey with Hubble (CLASH). We discover 257, 57,
and eight candidate galaxies at z∼6, 7, and 8 respectively, (322 in
total). The observed (lensed) magnitudes of the z∼6 candidates are as
bright as AB mag ∼23, making them among the brightest known at these
redshifts, comparable with discoveries from much wider, blank-field
surveys. RELICS demonstrates the efficiency of using strong
gravitational lenses to produce high-redshift samples in the epoch of
reionization. These brightly observed galaxies are excellent targets
for follow-up study with current and future observatories, including
the James Webb Space Telescope.
Description:
We target the 41 RELICS (Coe+, 2019, J/ApJ/884/85) clusters with two
orbits of HST WFC3/IR comprising observations in F105W, F125W, F140W,
and F160W. Five clusters are observed with an additional pointing, for
a total of 46 infrared fields. We take advantage of existing archival
ACS imaging, and for the 18 clusters without any F435W, F606W, and
F814W we observe three orbits total, with one orbit per filter. The
observations are split into two epochs separated by about a month.
In this work, we use two independent photometric-redshift fitting
codes to identify high-z galaxy candidates: the Bayesian
photometric-redshift code (BPZ v1.99.3; Benitez 2000ApJ...536..571B 2000ApJ...536..571B ;
Benitez+ 2004, J/ApJS/150/1 and Coe+ 2006, J/AJ/132/926) and the Easy
and Accurate Z (photometric redshifts) from Yale (EAZY;
Brammer+ 2008ApJ...686.1503B 2008ApJ...686.1503B). See Section 2.2.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 60 42 High-z number counts per cluster
table234.dat 349 322 z∼6, z∼7 and z∼8 galaxy candidates
behind 41 RELICS clusters (Tables 2, 3 and 4)
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See also:
J/ApJS/150/1 : VV29 and NGC 4676 HST photometry (Benitez+, 2004)
J/AJ/132/1729 : HUDF BVI-dropout sources (Beckwith+, 2006)
J/AJ/132/926 : Galaxies in the Hubble Ultra Deep Field (Coe+, 2006)
J/A+A/534/A109 : MCXC Meta-Catalog X-ray galaxy Clusters (Piffaretti+, 2011)
J/A+A/544/A156 : UltraVISTA Catalog Release DR1 (McCracken+, 2012)
J/ApJS/199/25 : CLASH sources for MACS1149.6+2223 (Postman+, 2012)
J/ApJS/199/34 : Clusters of galaxies in SDSS-III (Wen+, 2012)
J/MNRAS/432/2696 : Galaxy luminosity function at z = 7-9 (McLure+, 2013)
J/ApJ/769/52 : SDSS luminous red galaxies concentrations (Wong+, 2013)
J/MNRAS/440/2810 : Galaxy luminosity function at z ≃ 7 (Bowler+, 2014)
J/ApJ/792/76 : Lensed z∼6-8 galaxies behind CLASH clusters (Bradley+, 2014)
J/ApJ/800/18 : HST/WFC3 obs. of z∼7-8 galaxies in A2744 (Atek+, 2015)
J/ApJS/216/27 : Gal. clusters discovered in the SPT-SZ survey (Bleem+, 2015)
J/ApJ/803/34 : z∼4-10 galaxies from HST legacy fields (Bouwens+, 2015)
J/ApJ/810/71 : UV mag of cand. galaxies at 3~<z~<8.5 (Finkelstein+, 2015)
J/ApJ/814/L6 : CIII] emission in star-forming galaxies (Rigby+, 2015)
J/MNRAS/450/3665 : CoMaLit. III. LC2 catalog (Sereno+, 2015)
J/A+A/594/A27 : Planck Sunyaev-Zeldovich sources (PSZ2) (Planck+, 2016)
J/ApJ/843/41 : HST/WFC3 obs. of z∼2-8 gal. in HFF clusters (Bouwens+, 2017)
J/ApJ/835/113 : Gal. ≳6 from the Hubble Frontier Fields (Livermore+, 2017)
J/MNRAS/472/772 : Candidate LAEs at z=5.7 and z=6.6 (Matthee+, 2017)
J/ApJ/854/73 : Full-data results of HFF: galaxies z∼6-9 (Ishigaki+, 2018)
J/PASJ/70/S10 : GOLDRUSH I. UV magnitudes (Ono+, 2018)
J/ApJ/884/85 : RELICS: Reionization Lensing Cluster Survey (Coe+, 2019)
http://relics.stsci.edu/data.html : RELICS home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Cl Cluster identifier
14 A1 --- m_Cl RX J0603.3+4214-N and -S added by CDS
for coherence with Table234 (1)
16- 17 I2 h RAh Hour of right ascension (J2000)
19- 20 I2 min RAm Minute of right ascension (J2000)
22- 25 F4.1 s RAs Second of right ascension (J2000)
27 A1 --- DE- Sign of declination (J2000)
28- 29 I2 deg DEd Degree of declination (J2000)
31- 32 I2 arcmin DEm Arcminute of declination (J2000)
34- 37 F4.1 arcsec DEs Arcsecond of declination (J2000)
39- 43 F5.3 --- z [0.18/0.98]? Cluster redshift
45- 49 F5.2 10+14Msun Mass [4.9/16.2]? Planck mass
51- 52 I2 --- Ntot [0/28]? Total number of galaxies
54- 55 I2 --- Nz6 [0/25]? Number of z∼6 galaxies
57- 58 I2 --- Nz7 [0/10]? Number of z∼7 galaxies
60 I1 --- Nz8 [0/2]? Number of z∼8 galaxies
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Note (1): The "Toothbrush" cluster is the only RELICS cluster that required
two HST pointings that were not contiguous, yielding separate catalogs
for the two pointings (See also Coe+, 2019, J/ApJ/884/85).
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Byte-by-byte Description of file: table234.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Cl Cluster field
14 A1 --- m_Cl Component N or S for RX J0603.3+4214
16- 19 I4 --- ID [9/7437] ID within cluster field name
21- 25 F5.3 --- zAvg [5.5/8.4] Average redshift between
BPZ and EAZY (1)
27- 31 F5.3 --- e_zAvg [0.2/6.7] Lower 95% confidence limit
on zAvg (1)
33- 37 F5.3 --- E_zAvg [5.7/9.8] Upper 95% confidence limit
on zAvg (1)
39- 43 F5.3 --- zEAZY [0.7/8.6] EAZY redshift
45- 49 F5.3 --- e_zEAZY [0.2/6.9] Lower 95% confidence limit on zEAZY
51- 55 F5.3 --- E_zEAZY [1.3/9.8] Upper 95% confidence limit on zEAZY
57- 61 F5.3 --- zBPZ [0.7/8.3] BPZ redshift
63- 67 F5.3 --- e_zBPZ [0.3/7.1] Lower 95% confidence limit on zBPZ
69- 73 F5.3 --- E_zBPZ [3.6/8.7] Upper 95% confidence limit on zBPZ
75- 85 F11.7 deg RAdeg Right Ascension in degrees (J2000)
87- 97 F11.7 deg DEdeg Declination in degrees (J2000)
99 A1 --- l_F390wmag [no>] Limit flag on F390wmag (2)
102-108 F7.4 mag F390wmag [26.17/30]? HST/WFC3/UVIS F390W band magnitude
110-115 F6.4 mag e_F390wmag [0.2/1.8]? Uncertainty in F390wmag
117 A1 --- l_F435wmag [no>] Limit flag on F435wmag (2)
120-126 F7.4 mag F435wmag [25.8/33.7]? HST/ACS F435W band magnitude
129-134 F6.4 mag e_F435wmag [0.2/4.8]? Uncertainty in F435wmag
136 A1 --- l_F475wmag [no>] Limit flag on F475wmag (2)
138-144 F7.4 mag F475wmag [27.7/32.1]? HST/ACS F475W band magnitude
147-152 F6.4 mag e_F475wmag [0.5/2.8]? Uncertainty in F475wmag
154 A1 --- l_F555wmag [no>] Limit flag on F555wmag (2)
157-163 F7.4 mag F555wmag [27.77/32.2]? HST/ACS F555W magnitude
166-171 F6.4 mag e_F555wmag [0.3/3]? Uncertainty in F555wmag
173 A1 --- l_F606wmag [no>] Limit flag on F606wmag (2)
176-182 F7.4 mag F606wmag [26.3/33.6]? HST/ACS/WFC3/UVIS F606W
band magnitude
185-190 F6.4 mag e_F606wmag [0.18/4.2]? Uncertainty in F606wmag
192 A1 --- l_F625wmag [no>] Limit flag on F625wmag (2)
195-201 F7.4 mag F625wmag [28.29/32]? HST/ACS F625W band mag
204-209 F6.4 mag e_F625wmag [0.45/2.5]? Uncertainty in F625wmag
211 A1 --- l_F775wmag [no>] Limit flag on F775wmag (2)
213-219 F7.4 mag F775wmag [26.2/31.5]? HST/ACS F775W band magnitude
222-227 F6.4 mag e_F775wmag [0.089/3.4]? Uncertainty in F775wmag
229 A1 --- l_F814wmag [no>] Limit flag on F814wmag (2)
232-238 F7.4 mag F814wmag [23.89/32.5]? HST/ACS F814W band magnitude
241-246 F6.4 mag e_F814wmag [0.014/2.6]? Uncertainty in F814wmag
248 A1 --- l_F850lpmag [no>] Limit flag on F850lpmag (2)
250-256 F7.4 mag F850lpmag [25/30.9]? HST/ACS F850lp band magnitude
258-263 F6.4 mag e_F850lpmag [0.06/2.6]? Uncertainty in F850lpmag
265 A1 --- l_F105wmag [no>] Limit flag on F105wmag (2)
268-274 F7.4 mag F105wmag [22.98/30]? HST/WFC3 F105W band magnitude
276-281 F6.4 mag e_F105wmag [0.016/1.2]? Uncertainty in F105wmag
283 A1 --- l_F110wmag [no>] Limit flag on F110wmag (2)
285-291 F7.4 mag F110wmag [25.14/28.7]? HST/WFC3/IR F110W band magnitude
293-298 F6.4 mag e_F110wmag [0.019/0.17]? Uncertainty in F110wmag
300 A1 --- l_F125wmag [no>] Limit flag on F125wmag (2)
302-308 F7.4 mag F125wmag [22.75/29.76] HST/WFC3 F125W band magnitude
311-316 F6.4 mag e_F125wmag [0.02/1.8]? Uncertainty in F125wmag
318 A1 --- l_F140wmag [no>] Limit flag on F140wmag (2)
321-327 F7.4 mag F140wmag [22.75/29.8]? HST/WFC3 F140W band magnitude
329-334 F6.4 mag e_F140wmag [0.018/1.4]? Uncertainty in F140wmag
336-342 F7.4 mag F160wmag [22.77/28.3] HST/WFC3 F160W band magnitude
344-349 F6.4 mag e_F160wmag [0.01/0.31] Uncertainty in F160wmag
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Note (1): Quoted redshifts are the average of the BPZ and EAZY estimates unless
they differ by more than 1, in which case we adopt the higher
redshift solution. Quoted redshift uncertainties conservatively span
the 95% confidence intervals from both methods.
Note (2): Flag as follows:
n = no data obtained for that entry.
o = the target cluster was observed in the filter but the particular object
was not observed (usually because it fell outside of the field of view
for that filter).
> = 1σ upper limit for the magnitude (non-detection in the filter).
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Acknowledgements:
Dan Coe
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 16-Jul-2021