J/ApJ/846/145 PHAT. XIX. Formation history of M31 disk (Williams+, 2017)
Panchromatic Hubble Andromeda Treasury (PHAT).
XIX. The ancient star formation history of the M31 disk.
Williams B.F., Dolphin A.E., Dalcanton J.J., Weisz D.R., Bell E.F.,
Lewis A.R., Rosenfield P., Choi Y., Skillman E., Monachesi A.
<Astrophys. J., 846, 145 (2017)>
=2017ApJ...846..145W 2017ApJ...846..145W
ADC_Keywords: Galaxies, nearby ; Stars, ages ; Abundances, [Fe/H]
Keywords: galaxies: evolution; galaxies: individual (M31);
galaxies: stellar content
Abstract:
We map the star formation history across M31 by fitting stellar
evolution models to color-magnitude diagrams of each 83"x83"
(0.3x1.4kpc, deprojected) region of the Panchromatic Hubble Andromeda
Treasury (PHAT) survey outside of the innermost 6'x12' portion. We
find that most of the star formation occurred prior to ∼8Gyr ago,
followed by a relatively quiescent period until ∼4Gyr ago, a
subsequent star formation episode about 2Gyr ago, and a return to
relative quiescence. There appears to be little, if any, structure
visible for populations with ages older than 2Gyr, suggesting
significant mixing since that epoch. Finally, assuming a Kroupa
initial mass function from 0.1 to 100M☉, we find that the total
amount of star formation over the past 14Gyr in the area over which we
have fit models is 5x1010M☉. Fitting the radial distribution
of this star formation and assuming azimuthal symmetry,
(1.5±0.2)x1011M☉ of stars has formed in the M31 disk as a
whole, (9±2)x1010M☉ of which has likely survived to the
present after accounting for evolutionary effects. This mass is about
one-fifth of the total dynamical mass of M31.
Description:
The data for this study come from the Panchromatic Hubble Andromeda
Treasury (PHAT) survey (Dalcanton+ 2012ApJS..200...18D 2012ApJS..200...18D ; Williams+
2014, J/ApJS/215/9). Briefly, PHAT is a multiwavelength HST survey
mapping 414 contiguous HST fields of the northern M31 disk and bulge
in six broad wavelength bands from the near-ultraviolet to the
near-infrared. The survey obtained data in the F275W and F336W bands
with the UVIS detectors of the Wide-Field Camera 3 (WFC3) camera, the
F475W and F814W bands in the WFC detectors of the Advanced Camera for
Surveys (ACS) camera, and the F110W and F160W bands in the IR
detectors of the WFC3 camera.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 176 79296 Best-fit star formation rates (Msun/yr) for every
age and metallicity for each model set
in each 83"x83" region from our fixed chemical
enrichment fits
table2.dat 280 3304 Star formation rate surface densities
(10-4Msun/yr/arcmin^2) for every age bin
(combining all metallicities) for each model set
in each 83"x83" region from our fixed chemical
enrichment fits
table7.dat 176 80049 Best-fit star formation rates (Msun/yr)for every
age and metallicity for each model set in each
83"x83" region from our free-metallicity fits
table8.dat 287 3304 Star formation rate surface densities
(10-4Msun/yr/arcmin^2) for every age bin
(combining all metallicities) for each model set
in each 83"x83" region from our
free-metallicity fits
--------------------------------------------------------------------------------
See also:
J/ApJS/184/152 : Deep optical photometry in M31 (Brown+, 2009)
J/A+A/509/A61 : Long slit spectroscopy in M31 (Saglia+, 2010)
J/ApJ/734/L22 : ACS Nearby Galaxy Survey Treasury (Williams+, 2011)
J/ApJS/215/9 : PHAT X. UV-IR photometry of M31 stars (Williams+, 2014)
Byte-by-byte Description of file: table[17].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- Model Model set (BASTI, MIST, PARSEC or Padova) (G1)
8- 8 I1 h RAh [0] Hour of Right Ascension (J2000)
10- 11 I2 min RAm [42/47] Minute of Right Ascension (J2000)
13- 17 F5.2 s RAs Second of Right Ascension (J2000)
18 A1 --- DE- [+] Sign of Declination (J2000)
19- 20 I2 deg DEd [41/42] Degree of Declination (J2000)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000)
25- 28 F4.1 arcsec DEs Arcsecond of Declination (J2000)
30- 34 F5.2 [Sun] [Fe/H] [-2.3/0.2] Metallicty, log(Z/Z_sun)
36- 43 A8 Msun/yr Age1 [0/0.003] Age range, 0.0-0.3Gyr
45- 52 A8 Msun/yr Age2 [0/0.02] Age range, 0.3-0.4Gyr
54- 60 A7 Msun/yr Age3 [0/0.08] Age range, 0.4-0.5Gyr
62- 69 A8 Msun/yr Age4 [0/0.06] Age range, 0.5-0.6Gyr
71- 78 A8 Msun/yr Age5 [0/0.2] Age range, 0.6-0.8Gyr
80- 87 A8 Msun/yr Age6 [0/0.08] Age range, 0.8-1.0Gyr
89- 95 A7 Msun/yr Age7 [0/0.2] Age range, 1.0-1.3Gyr
97-104 A8 Msun/yr Age8 [0/0.2] Age range, 1.3-1.6Gyr
106-113 A8 Msun/yr Age9 [0/0.06] Age range, 1.6-2.0Gyr
115-122 A8 Msun/yr Age10 [0/0.1] Age range, 2.0-2.5Gyr
124-131 A8 Msun/yr Age11 [0/0.2] Age range, 2.5-3.2Gyr
133-140 A8 Msun/yr Age12 [0/0.05] Age range, 3.2-4.0Gyr
142-149 A8 Msun/yr Age13 [0/0.04] Age range, 4.0-5.0Gyr
151-158 A8 Msun/yr Age14 [0/0.04] Age range, 5.0-6.3Gyr
160-167 A8 Msun/yr Age15 [0/0.04] Age range, 6.3-7.9Gyr
169-176 A8 Msun/yr Age16 [0/0.06] Age range, 7.9-14.1Gyr
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- Model Model set (BASTI, MIST, PARSEC or
Padova) (G1)
8- 8 I1 h RAh [0] Hour of Right Ascension (J2000)
10- 11 I2 min RAm [42/47] Minute of Right Ascension
(J2000)
13- 17 F5.2 s RAs Second of Right Ascension (J2000)
18 A1 --- DE- [+] Sign of Declination (J2000)
19- 20 I2 deg DEd [41/42] Degree of Declination
(J2000)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000)
25- 28 F4.1 arcsec DEs Arcsecond of Declination (J2000)
30- 33 F4.1 10-4Msun/yr/arcmin2 Age1 [0/13.1] Age range, 0.0-0.3Gyr
35- 37 F3.1 10-4Msun/yr/arcmin2 E_Age1 [0/2.9] Upper uncertainty on Age1
39- 41 F3.1 10-4Msun/yr/arcmin2 e_Age1 [0/3] Lower uncertainty on Age1
43- 46 F4.1 10-4Msun/yr/arcmin2 Age2 [0/89.4] Age range, 0.3-0.4Gyr
48- 50 F3.1 10-4Msun/yr/arcmin2 E_Age2 [0/7.2] Upper uncertainty on Age2
52- 55 F4.1 10-4Msun/yr/arcmin2 e_Age2 [0/10.2] Lower uncertainty on Age2
57- 61 F5.1 10-4Msun/yr/arcmin2 Age3 [0/589.7] Age range, 0.4-0.5Gyr
63- 66 F4.1 10-4Msun/yr/arcmin2 E_Age3 [0/21.1] Upper uncertainty on Age3
68- 71 F4.1 10-4Msun/yr/arcmin2 e_Age3 [0/37.8] Lower uncertainty on Age3
73- 77 F5.1 10-4Msun/yr/arcmin2 Age4 [0/323.6] Age range, 0.5-0.6Gyr
79- 82 F4.1 10-4Msun/yr/arcmin2 E_Age4 [0/36.1] Upper uncertainty on Age4
84- 87 F4.1 10-4Msun/yr/arcmin2 e_Age4 [0/73.4] Lower uncertainty on Age4
89- 93 F5.1 10-4Msun/yr/arcmin2 Age5 [0/973.5] Age range, 0.6-0.8Gyr
95- 98 F4.1 10-4Msun/yr/arcmin2 E_Age5 [0/97.2] Upper uncertainty on Age5
100-103 F4.1 10-4Msun/yr/arcmin2 e_Age5 [0/60.7] Lower uncertainty on Age5
105-109 F5.1 10-4Msun/yr/arcmin2 Age6 [0/632.6] Age range, 0.8-1.0Gyr
111-114 F4.1 10-4Msun/yr/arcmin2 E_Age6 [0/62] Upper uncertainty on Age6
116-119 F4.1 10-4Msun/yr/arcmin2 e_Age6 [0/90] Lower uncertainty on Age6
121-125 F5.1 10-4Msun/yr/arcmin2 Age7 [0/797] Age range, 1.0-1.3Gyr
127-130 F4.1 10-4Msun/yr/arcmin2 E_Age7 [0/81.5] Upper uncertainty on Age7
132-136 F5.1 10-4Msun/yr/arcmin2 e_Age7 [0/132.1] Lower uncertainty on Age7
138-142 F5.1 10-4Msun/yr/arcmin2 Age8 [0/685.8] Age range, 1.3-1.6Gyr
144-147 F4.1 10-4Msun/yr/arcmin2 E_Age8 [0/49] Upper uncertainty on Age8
149-153 F5.1 10-4Msun/yr/arcmin2 e_Age8 [0/114.7] Lower uncertainty on Age8
155-159 F5.1 10-4Msun/yr/arcmin2 Age9 [0/433] Age range, 1.6-2.0Gyr
161-164 F4.1 10-4Msun/yr/arcmin2 E_Age9 [0/42] Upper uncertainty on Age9
166-169 F4.1 10-4Msun/yr/arcmin2 e_Age9 [0/67.8] Lower uncertainty on Age9
171-175 F5.1 10-4Msun/yr/arcmin2 Age10 [0/788.4] Age range, 2.0-2.5Gyr
177-180 F4.1 10-4Msun/yr/arcmin2 E_Age10 [0/63.4] Upper uncertainty on Age10
182-185 F4.1 10-4Msun/yr/arcmin2 e_Age10 [0/91] Lower uncertainty on Age10
187-191 F5.1 10-4Msun/yr/arcmin2 Age11 [0/580] Age range, 2.5-3.2Gyr
193-196 F4.1 10-4Msun/yr/arcmin2 E_Age11 [0/59] Upper uncertainty on Age11
198-201 F4.1 10-4Msun/yr/arcmin2 e_Age11 [0/99.1] Lower uncertainty on Age11
203-207 F5.1 10-4Msun/yr/arcmin2 Age12 [0/132] Age range, 3.2-4.0Gyr
209-212 F4.1 10-4Msun/yr/arcmin2 E_Age12 [0/31.3] Upper uncertainty on Age12
214-217 F4.1 10-4Msun/yr/arcmin2 e_Age12 [0/25.4] Lower uncertainty on Age12
219-222 F4.1 10-4Msun/yr/arcmin2 Age13 [0/75.3] Age range, 4.0-5.0Gyr
224-227 F4.1 10-4Msun/yr/arcmin2 E_Age13 [0/21.6] Upper uncertainty on Age13
229-232 F4.1 10-4Msun/yr/arcmin2 e_Age13 [0/20.0] Lower uncertainty on Age13
234-238 F5.1 10-4Msun/yr/arcmin2 Age14 [0/129.4] Age range, 5.0-6.3Gyr
240-243 F4.1 10-4Msun/yr/arcmin2 E_Age14 [0/15.5] Upper uncertainty on Age14
245-248 F4.1 10-4Msun/yr/arcmin2 e_Age14 [0/36.6] Lower uncertainty on Age14
250-254 F5.1 10-4Msun/yr/arcmin2 Age15 [0/153.5] Age range, 6.3-7.9Gyr
256-259 F4.1 10-4Msun/yr/arcmin2 E_Age15 [0/48.1] Upper uncertainty on Age15
261-264 F4.1 10-4Msun/yr/arcmin2 e_Age15 [0/35.1] Lower uncertainty on Age15
266-270 F5.1 10-4Msun/yr/arcmin2 Age16 [1.4/919] Age range, 7.9-14.1Gyr
272-275 F4.1 10-4Msun/yr/arcmin2 E_Age16 [0/72.3] Upper uncertainty on Age16
277-280 F4.1 10-4Msun/yr/arcmin2 e_Age16 [0.1/28] Lower uncertainty on Age16
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- Model Model set (BASTI, MIST, PARSEC or
Padova) (G1)
8- 8 I1 h RAh [0] Hour of Right Ascension (J2000)
10- 11 I2 min RAm [42/47] Minute of Right Ascension
(J2000)
13- 17 F5.2 s RAs Second of Right Ascension (J2000)
18 A1 --- DE- [+] Sign of Declination (J2000)
19- 20 I2 deg DEd [41/42] Degree of Declination
(J2000)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000)
25- 28 F4.1 arcsec DEs Arcsecond of Declination (J2000)
30- 33 F4.1 10-4Msun/yr/arcmin2 Age1 [0/18.1] Age range, 0.0-0.3Gyr
35- 37 F3.1 10-4Msun/yr/arcmin2 E_Age1 [0/6.1] Upper uncertainty on Age1
39- 41 F3.1 10-4Msun/yr/arcmin2 e_Age1 [0/5.8] Lower uncertainty on Age1
43- 46 F4.1 10-4Msun/yr/arcmin2 Age2 [0/46.1] Age range, 0.3-0.4Gyr
48- 51 F4.1 10-4Msun/yr/arcmin2 E_Age2 [0/10.6] Upper uncertainty on Age2
53- 56 F4.1 10-4Msun/yr/arcmin2 e_Age2 [0/19.7] Lower uncertainty on Age2
58- 62 F5.1 10-4Msun/yr/arcmin2 Age3 [0/341.7] Age range, 0.4-0.5Gyr
64- 67 F4.1 10-4Msun/yr/arcmin2 E_Age3 [0/58.1] Upper uncertainty on Age3
69- 72 F4.1 10-4Msun/yr/arcmin2 e_Age3 [0/41.7] Lower uncertainty on Age3
74- 78 F5.1 10-4Msun/yr/arcmin2 Age4 [0/482] Age range, 0.5-0.6Gyr
80- 83 F4.1 10-4Msun/yr/arcmin2 E_Age4 [0/54.5] Upper uncertainty on Age4
85- 88 F4.1 10-4Msun/yr/arcmin2 e_Age4 [0/43.5] Lower uncertainty on Age4
90- 94 F5.1 10-4Msun/yr/arcmin2 Age5 [0/212.1] Age range, 0.6-0.8Gyr
96-100 F5.1 10-4Msun/yr/arcmin2 E_Age5 [0/151.7] Upper uncertainty on Age5
102-105 F4.1 10-4Msun/yr/arcmin2 e_Age5 [0/69.7] Lower uncertainty on Age5
107-111 F5.1 10-4Msun/yr/arcmin2 Age6 [0/487.5] Age range, 0.8-1.0Gyr
113-116 F4.1 10-4Msun/yr/arcmin2 E_Age6 [0/32.1] Upper uncertainty on Age6
118-121 F4.1 10-4Msun/yr/arcmin2 e_Age6 [0/95] Lower uncertainty on Age6
123-127 F5.1 10-4Msun/yr/arcmin2 Age7 [0/711.8] Age range, 1.0-1.3Gyr
129-133 F5.1 10-4Msun/yr/arcmin2 E_Age7 [0/105.7] Upper uncertainty on Age7
135-138 F4.1 10-4Msun/yr/arcmin2 e_Age7 [0/73] Lower uncertainty on Age7
140-144 F5.1 10-4Msun/yr/arcmin2 Age8 [0/941.7] Age range, 1.3-1.6Gyr
146-150 F5.1 10-4Msun/yr/arcmin2 E_Age8 [0/109] Upper uncertainty on Age8
152-155 F4.1 10-4Msun/yr/arcmin2 e_Age8 [0/51.4] Lower uncertainty on Age8
157-161 F5.1 10-4Msun/yr/arcmin2 Age9 [0/406.6] Age range, 1.6-2.0Gyr
163-166 F4.1 10-4Msun/yr/arcmin2 E_Age9 [0/49] Upper uncertainty on Age9
168-171 F4.1 10-4Msun/yr/arcmin2 e_Age9 [0/49.5] Lower uncertainty on Age9
173-177 F5.1 10-4Msun/yr/arcmin2 Age10 [0/591.7] Age range, 2.0-2.5Gyr
179-182 F4.1 10-4Msun/yr/arcmin2 E_Age10 [0/72.2] Upper uncertainty on Age10
184-187 F4.1 10-4Msun/yr/arcmin2 e_Age10 [0/68.4] Lower uncertainty on Age10
189-194 F6.1 10-4Msun/yr/arcmin2 Age11 [0/1174.8] Age range, 2.5-3.2Gyr
196-200 F5.1 10-4Msun/yr/arcmin2 E_Age11 [0/114.5] Upper uncertainty on Age11
202-205 F4.1 10-4Msun/yr/arcmin2 e_Age11 [0/76.1] Lower uncertainty on Age11
207-211 F5.1 10-4Msun/yr/arcmin2 Age12 [0/261] Age range, 3.2-4.0Gyr
213-216 F4.1 10-4Msun/yr/arcmin2 E_Age12 [0/73.3] Upper uncertainty on Age12
218-222 F5.1 10-4Msun/yr/arcmin2 e_Age12 [0/106] Lower uncertainty on Age12
224-228 F5.1 10-4Msun/yr/arcmin2 Age13 [0/206] Age range, 4.0-5.0Gyr
230-233 F4.1 10-4Msun/yr/arcmin2 E_Age13 [0/84.0] Upper uncertainty on Age13
235-238 F4.1 10-4Msun/yr/arcmin2 e_Age13 [0/65.8] Lower uncertainty on Age13
240-244 F5.1 10-4Msun/yr/arcmin2 Age14 [0/180.4] Age range, 5.0-6.3Gyr
246-249 F4.1 10-4Msun/yr/arcmin2 E_Age14 [0/59.6] Upper uncertainty on Age14
251-254 F4.1 10-4Msun/yr/arcmin2 e_Age14 [0/78.1] Lower uncertainty on Age14
256-260 F5.1 10-4Msun/yr/arcmin2 Age15 [0/317] Age range, 6.3-7.9Gyr
262-266 F5.1 10-4Msun/yr/arcmin2 E_Age15 [0/121.8] Upper uncertainty on Age15
268-271 F4.1 10-4Msun/yr/arcmin2 e_Age15 [0/69.5] Lower uncertainty on Age15
273-277 F5.1 10-4Msun/yr/arcmin2 Age16 [1.9/976] Age range, 7.9-14.1Gyr
279-282 F4.1 10-4Msun/yr/arcmin2 E_Age16 [0/64.5] Upper uncertainty on Age16
284-287 F4.1 10-4Msun/yr/arcmin2 e_Age16 [0/68.3] Lower uncertainty on Age16
--------------------------------------------------------------------------------
Global note:
Note (G1): The Padova (Marigo+ 2008A&A...482..883M 2008A&A...482..883M ;
Girardi+ 2010ApJ...724.1030G 2010ApJ...724.1030G), PARSEC (Bressan+ 2012MNRAS.427..127B 2012MNRAS.427..127B),
BaSTI (Pietrinferni+ 2004ApJ...612..168P 2004ApJ...612..168P ;
Cassisi+ 2006MmSAI..77...71C 2006MmSAI..77...71C ; Pietrinferni+ 2013A&A...558A..46P 2013A&A...558A..46P),
and MIST (Choi+ 2016ApJ...823..102C 2016ApJ...823..102C) models. See section 2.
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History:
From electronic version of the journal
References:
Dalcanton et al. 2012ApJS..200...18D 2012ApJS..200...18D
Rosenfield et al. Paper I 2012ApJ...755..131R 2012ApJ...755..131R
Williams et al. Paper II 2012ApJ...759...46W 2012ApJ...759...46W
Beerman et al. Paper III 2012ApJ...760..104B 2012ApJ...760..104B
Weisz et al. Paper IV 2013ApJ...762..123W 2013ApJ...762..123W Cat. J/ApJ/762/123
Fouesneau et al. Paper V 2014ApJ...786..117F 2014ApJ...786..117F
Simones et al. Paper VI 2014ApJ...788...12S 2014ApJ...788...12S
Dong et al. Paper VII 2014ApJ...785..136D 2014ApJ...785..136D
Dalcanton et al. Paper VIII 2015ApJ...814....3D 2015ApJ...814....3D
Veyette et al. Paper IX 2014ApJ...792..121V 2014ApJ...792..121V
Williams et al. Paper X 2014ApJS..215....9W 2014ApJS..215....9W Cat. J/ApJS/215/9
Lewis et al. Paper XI 2015ApJ...805..183L 2015ApJ...805..183L
Gregersen et al. Paper XII 2015AJ....150..189G 2015AJ....150..189G
Wagner-Kaiser et al. Paper XIII 2015MNRAS.451..724W 2015MNRAS.451..724W Cat. J/MNRAS/451/724
Senchyna et al. Paper XIV 2015ApJ...813...31S 2015ApJ...813...31S
Gordon et al. Paper XV 2016ApJ...826..104G 2016ApJ...826..104G
Johnson et al. Paper XVI 2016ApJ...827...33J 2016ApJ...827...33J Cat. J/ApJ/827/33
Lewis et al. Paper XVII 2017ApJ...834...70L 2017ApJ...834...70L
Johnson et al. Paper XVIII 2017ApJ...839...78J 2017ApJ...839...78J
Williams et al. Paper XIX 2017ApJ...846..145W 2017ApJ...846..145W This catalog
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 24-May-2018