J/ApJS/253/53 PHATTER. I. HST obs. of 22million stars in M33 (Williams+, 2021)
The Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region
(PHATTER).
I. Ultraviolet to infrared photometry of 22 million stars in M33.
Williams B.F., Durbin M.J., Dalcanton J.J., Lang D., Girardi L.,
Smercina A., Dolphin A., Weisz D.R., Choi Y., Bell E.F., Rosolowsky E.,
Skillman E., Koch E.W., Lindberg C.W., Hagen L., Gordon K.D., Seth A.,
Gilbert K., Guhathakurta P., Lauer T., Bianchi L.
<Astrophys. J. Suppl. Ser., 253, 53-53 (2021)>
=2021ApJS..253...53W 2021ApJS..253...53W (SIMBAD/NED BibCode)
ADC_Keywords: Photometry, HST; Ultraviolet; Optical; Infrared; Galaxies, nearby
Keywords: Triangulum Galaxy; Stellar populations; Local Group
Multi-color photometry; Celestial objects catalogs
Abstract:
We present panchromatic resolved stellar photometry for 22 million
stars in the Local Group dwarf spiral Triangulum (M33), derived from
Hubble Space Telescope observations with the Advanced Camera for
Surveys in the optical (F475W, F814W), and the Wide Field Camera 3 in
the near-ultraviolet (F275W, F336W) and near-infrared (F110W, F160W)
bands. The large, contiguous survey area covers ∼14kpc2 and extends
to 3.5kpc (14', or 1.5-2 scale lengths) from the center of M33. The
PHATTER observing strategy and photometry technique closely mimics
that of Panchromatic Hubble Andromeda Treasury, but with updated
photometry techniques that take full advantage of all overlapping
pointings (aligned to within <5-10mas) and improved treatment of
spatially varying point-spread functions. The photometry reaches a
completeness-limited depth of F475W∼28.5 in the lowest surface density
regions observed in M33 and F475W∼26.5 in the most crowded regions
found near the center of M33. We find the young populations trace
several relatively tight arms, while the old populations show a clear,
looser two-armed structure. We present extensive analysis of the data
quality, including artificial star tests to quantify completeness,
photometric uncertainties, and flux biases.
Description:
We build up this survey area using the same Panchromatic Hubble
Andromeda Treasury (PHAT) tiling strategy, as described in
Dalcanton et al. (2012ApJS..200...18D 2012ApJS..200...18D).
Observations for this program (GO-14610) were taken between
2017-February-21 and 2018-February-25.
A table of the HST exposures at each position is supplied in Table 1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 99 972 Exposure data for all fields
table3.dat 159 187116 Artificial star data
table5.dat 52 491 Bias and uncertainty as a function of magnitude
and stellar density
table6.dat 118 21980690 Photometric data
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See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/AJ/110/1649 : VI photometry near the M33 nucleus (Mighell+ 1995)
J/ApJ/469/629 : UV-brightest stars of M33 and its nucleus (Massey+ 1996)
J/ApJS/122/431 : Star Clusters in M33 (Chandar+, 1999)
J/A+A/366/498 : VI photometry of M33 star clusters (Chandar+, 2001)
J/ApJS/149/343 : Giant molecular clouds in M33 (Engargiola+, 2003)
J/AJ/131/2478 : M31 and M33 UBVRI photometry (Massey+, 2006)
J/ApJ/661/830 : Giant molecular clouds of M33 (Rosolowsky+, 2007)
J/ApJ/664/850 : Spitzer observations of stars in M33 (McQuinn+, 2007)
J/ApJ/675/1213 : Abundances in M33 HII regions (Rosolowsky+, 2008)
J/A+A/487/131 : JHKs photometry of LPVs in M33 (Cioni+, 2008)
J/AcA/59/47 : HST photometry of M33 stellar clusters (Zloczewski+, 2009)
J/ApJ/696/729 : Fluxes and abundances of PNe in M33 (Magrini+, 2009)
J/ApJ/699/839 : Newly identified star clusters in M33. II. (San Roman+, 2009)
J/A+A/512/A63 : Abundances of M33 HII regions (Magrini+, 2010)
J/A+A/522/A3 : M33 CO(2-1) and HI integrated intensity maps (Gratier+, 2010)
J/ApJ/724/799 : RR Lyrae variables in M33. II. (Yang+, 2010)
J/ApJS/193/31 : M33 Chandra ACIS survey: final catalog (Tullmann+, 2011)
J/AJ/144/113 : Cepheids & companions in M33 from HST images (Chavez+, 2012)
J/ApJ/795/170 : Sample SNRs for M31 and M33 (Jennings+, 2014)
J/ApJS/215/9 : PHAT X. UV-IR photometry of M31 stars (Williams+, 2014)
J/ApJ/802/127 : PHAT stellar cluster survey. II. AP catalog (Johnson+, 2015)
J/ApJS/218/9 : Deep XMM-Newton survey of M33 (Williams+, 2015)
J/MNRAS/451/3400 : Star clusters in M33 (Beasley+, 2015)
J/A+A/586/A37 : M33 center and BCLMP302 [CII] spectroscopy (Mookerjea+, 2016)
J/ApJ/825/50 : Variable stars in M31 & M33. III. YSGs & RSGs (Gordon+, 2016)
J/ApJ/836/64 : Luminous variable stars in M31 & M33. IV. (Humphreys+, 2017)
J/ApJ/842/97 : Spectroscopic obs. of 413 HII regions in M33 (Lin+, 2017)
J/ApJ/846/145 : PHAT. XIX. Formation history of M31 disk (Williams+, 2017)
J/ApJ/868/55 : Structure of M31 halo. II. PAndAS (McConnachie+, 2018)
J/ApJS/241/37 : 1.4 and 5GHz deep JVLA radio survey of M33 (White+, 2019)
J/ApJS/260/41 : Dust extinction law in nearby galaxies. II. M33 (Wang+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Target Target Name
18- 19 I2 h RAh [1] Hour of Right Ascension (J2000)
21- 22 I2 min RAm [33/34] Minute of Right Ascension (J2000)
24- 28 F5.2 s RAs Second of Right Ascension (J2000)
30 A1 --- DE- [+] Sign of the Declination (J2000)
31- 32 I2 deg DEd [30] Degree of Declination (J2000)
34- 35 I2 arcmin DEm [30/49] Arcminute of Declination (J2000)
37- 41 F5.2 arcsec DEs Arcsecond of Declination (J2000)
43- 61 A19 "datime" Date ISO 8601 Date/Time at start of exposure
63- 68 F6.2 s Exp [10/700] Exposure time
70- 73 A4 --- Inst Instrument ("WFC3" or "ACS")
75- 85 A11 --- Aper Instrument aperture
87- 91 A5 --- Filt Filter
93- 99 F7.2 deg Orient [-133.3/99.84] Orientation
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 10 F10.7 deg RAdeg [23.43/23.57] Right Ascension (J2000)
12- 21 F10.7 deg DEdeg [30.64/30.84] Declination (J2000)
23- 28 F6.3 mag F275W [15.47/35.5] Input F275W magnitude
30- 35 F6.3 mag dF275W [-9.5/10.3]?=99.999 Magnitude difference,
F275W out - in
37- 42 F6.1 --- F275Wsnr [-6.1/1323] Signal-to-noise ratio, F275W
44 A1 --- F275Wgst [TF] Fulfills GST quality requirements (G1)
46- 51 F6.3 mag F336W [16/32.31] Input F336W magnitude
53- 58 F6.3 mag dF336W [-8.2/9.9]?=99.999 Magnitude difference,
F336W out - in
60- 65 F6.1 --- F336Wsnr [-5.8/1718] Signal-to-noise ratio, F336W
67 A1 --- F336Wgst [TF] Fulfills GST quality requirements (G1)
69- 74 F6.3 mag F475W [17.75/30.86] Input F475W magnitude
76- 81 F6.3 mag dF475W [-8.62/8.6]?=99.999 Magnitude difference,
F475W out - in
83- 88 F6.1 --- F475Wsnr [-12.3/1955] Signal-to-noise ratio, F475W
90 A1 --- F475Wgst [TF] Fulfills GST quality requirements (G1)
92- 97 F6.3 mag F814W [18/29.13] Input F814W magnitude
99-104 F6.3 mag dF814W [-8.7/9.3]?=99.999 Magnitude difference,
F814W out - in
106-111 F6.1 --- F814Wsnr [-8.5/1719] Signal-to-noise ratio, F814W
113 A1 --- F814Wgst [TF] Fulfills GST quality requirements (G1)
115-120 F6.3 mag F110W [16.87/28.58] Input F110W magnitude
122-127 F6.3 mag dF110W [-9.3/12.7]?=99.999 Magnitude difference,
F110W out - in
129-134 F6.1 --- F110Wsnr [-7.2/1967] Signal-to-noise ratio, F110W
136 A1 --- F110Wgst [TF] Fulfills GST quality requirements (G1)
138-143 F6.3 mag F160W [15.84/28] Input F160W magnitude
145-150 F6.3 mag dF160W [-9.9/9.6]?=99.999 Magnitude difference,
F160W out - in
152-157 F6.1 --- F160Wsnr [-10.9/2262] Signal-to-noise ratio, F160W
159 A1 --- F160Wgst [TF] Fulfills GST quality requirements (G1)
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 4 F4.2 arcsec-2 Den1 [0/0.9] Lower range of density,
star counts per square arcsec (1)
6 A1 --- --- [-]
8- 11 F4.2 arcsec-2 Den2 [0.15/0.9]? Upper range of density,
star counts per square arcsec (1)
13- 17 A5 --- Filt Filter
19- 22 F4.1 mag Bin [17.5/28] Magnitude bin
24- 30 F7.4 mag Bias [-0.5/0.18] Photometric bias
(median output - input)
32- 37 F6.4 mag Err [0.001/0.52] AST-derived uncertainty (2)
39- 44 F6.4 mag DOLPHOT [0.001/0.24] DOLPHOT-reported uncertainty
46- 52 F7.4 --- Ratio [0.87/29.05] AST/DOLPHOT uncertainty ratio
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Note (1): Star counts per square arcsec with 19.7<F160W<20.7
Note (2): AST-derived uncertainty corresponds to the 16th to 84th percentile
range divided by 2.
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 10 F10.7 deg RAdeg [23.34/23.67] Right Ascension (J2000)
12- 21 F10.7 deg DEdeg [30.48/30.86] Declination (J2000)
23- 28 F6.3 mag F275W [14.69/44.76]?=99.999 Measured HST/WFC3 F275W
near-UV magnitude
30- 35 F6.1 --- F275Wsnr [-9.6/606.5] Signal-to-noise ratio, F275W
37 A1 --- F275Wgst [TF] Fulfills GST quality requirements (G1)
39- 44 F6.3 mag F336W [15.62/46.2]?=99.999 Measured HST/WFC3 F336W
near-UV magnitude
46- 51 F6.1 --- F336Wsnr [-13.3/869.5] Signal-to-noise ratio, F336W
53 A1 --- F336Wgst [TF] Fulfills GST quality requirements (G1)
55- 60 F6.3 mag F475W [16.72/45.47]?=99.999 Measured HST/ACS
optical F475W magnitude
62- 67 F6.1 --- F475Wsnr [-23.6/1758] Signal-to-noise ratio, F475W
69 A1 --- F475Wgst [TF] Fulfills GST quality requirements (G1)
71- 76 F6.3 mag F814W [14.14/44.45]?=99.999 Measured HST/ACS optical
F814W magnitude
78- 83 F6.1 --- F814Wsnr [-19.2/1701.3] Signal-to-noise ratio, F814W
85 A1 --- F814Wgst [TF] Fulfills GST quality requirements (G1)
87- 92 F6.3 mag F110W [13/42.6]?=99.999 Measured HST/WFC3 near-IR
F110W magnitude
94- 99 F6.1 --- F110Wsnr [-7.9/8071.1] Signal-to-noise ratio, F110W
101 A1 --- F110Wgst [TF] Fulfills GST quality requirements (G1)
103-108 F6.3 mag F160W [12/42.13]?=99.999 Measured HST/WFC3 near-IR
F160W magnitude
110-116 F7.1 --- F160Wsnr [-21.4/10410] Signal-to-noise ratio, F160W
118 A1 --- F160Wgst [TF] Fulfills GST quality requirements (G1)
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Global notes:
Note (G1): This flag is set to "T" for sources that pass our quality checks
detailed in Section 2.2.4, and to "F" for sources that do not. If
a source has a T in any band, it is likely to be a real star in M33.
However, it still may have "F" flags in other bands, indicating
that the star was not reliably measured in that band. Only sources
with "F" values in all bands are unlikely to be stars in M33.
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History:
From electronic version of the journal
References:
Lazzarini et al. Paper II. 2022ApJ...934...76L 2022ApJ...934...76L
Wainer et al. Paper III. 2022ApJ...928...15W 2022ApJ...928...15W
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 02-Aug-2022