2004A&A...425..489C

Query : 2004A&A...425..489C

2004A&A...425..489C - Astronomy and Astrophysics, volume 425, 489-508 (2004/10-2)

A search for late-type supergiants in the inner regions of the Milky Way.

COMERON F., TORRA J., CHIAPPINI C., FIGUERAS F., IVANOV V.D. and RIBAS S.J.

Abstract (from CDS):

We present the results of a narrow-band infrared imaging survey of a narrow strip (12' wide) around the Galactic equator between 6° and 21° of galactic longitude aimed at detecting field stars with strong CO absorption, mainly late-type giants and supergiants. Our observations include follow-up low resolution spectroscopy (R=980) of 191 selected candidates in the H and K bands. Most of these objects have photometric and spectroscopic characteristics consistent with their being red giants, and some display broad, strong absorption wings due to water vapor absorption between the H and K bands. We also identify in our sample 18 good supergiant candidates characterized by their lack of noticeable water absorption, strong CO bands in the H and K windows, and HKS photometry suggestive of high intrinsic luminosity and extinction reaching up to AV≃40mag. Another 9 candidates share the same features except for weak H2O absorption, which is also observed among some M supergiants in the solar neighbourhood. Interesting differences are noticed when comparing our stars with a local sample of late-type giants and supergiants, as well as with a sample of red giants in globular clusters of moderately subsolar metallicity and to a sample of bulge stars. A large fraction of the stars in our sample have CaI and NaI features markedly stronger than those typical in the local reference sample (both giants and supergiants), whereas the equivalent widths of the CO bands are similar or weaker. In this regard, our stars in the inner Milky Way disk display differences very similar to those identified by other authors between cool giants and supergiants near the galactic center and their counterparts in the solar neighbourhood. We propose that the systematic spectroscopic differences of our inner Galaxy stars are due to their higher metallicities that cause deeper mixing in their mantles, resulting in lower surface abundances of C and O and higher abundances of CN, which contribute to the strength of the CaI and NaI features at low resolution. Our results stress the limitations of using local stars as templates for the study of composite cool stellar populations such as central starbursts in galaxies.

Abstract Copyright: ∼

Journal keyword(s): stars: late-type - stars: supergiants - Galaxy: abundances - Galaxy: disk - Galaxy: stellar contents - Galaxy: structure

VizieR on-line data: <Available at CDS (J/A+A/425/489): table1.dat sp/*>

Nomenclature: Table 1: [CTC2004] NNN N=195 among (Nos 1-202).

Simbad objects: 202

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Number of rows : 202
N Identifier Otype ICRS (J2000)
RA 		ICRS (J2000)
DEC 		Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2024 		#notes
1 * alf Ori s*r 05 55 10.30536 +07 24 25.4304 4.38 2.27 0.42 -1.17 -2.45 M1-M2Ia-Iab 1670 0
2 NGC 5927 GlC 15 28 00.69 -50 40 22.9           ~ 462 0
3 GCIRS 7 * 17 45 39.987 -29 00 22.24           M2 369 0
4 NGC 6440 GlC 17 48 52.67 -20 21 34.5           ~ 550 0
5 2MASS J17585882-2343036 * 17 58 58.8271143576 -23 43 03.583981308           ~ 1 0
6 2MASS J17591760-2348023 * 17 59 17.6058842952 -23 48 02.305567188           ~ 1 0
7 2MASS J17591998-2349348 * 17 59 19.9843305336 -23 49 34.786090920           ~ 1 0
8 2MASS J17592045-2351116 * 17 59 20.45 -23 51 11.7           ~ 1 0
9 2MASS J17592062-2334010 * 17 59 20.6203177872 -23 34 01.042725396           ~ 1 0
10 2MASS J17592506-2332498 * 17 59 25.07 -23 32 49.9           ~ 1 0
11 2MASS J17592743-2332059 * 17 59 27.4395592896 -23 32 05.954410716           ~ 1 0
12 2MASS J17592935-2331096 * 17 59 29.3581955880 -23 31 09.668418780           ~ 1 0
13 2MASS J17593362-2350413 * 17 59 33.6276826824 -23 50 41.368082892           ~ 1 0
14 2MASS J17593392-2338004 * 17 59 33.9206370264 -23 38 00.464735112           ~ 1 0
15 2MASS J17593664-2341162 * 17 59 36.64 -23 41 16.3           ~ 1 0
16 2MASS J17594780-2323331 * 17 59 47.8130863464 -23 23 33.070362900           ~ 1 0
17 2MASS J17595282-2320377 * 17 59 52.8292569432 -23 20 37.704604632           ~ 1 0
18 2MASS J18001385-2323009 * 18 00 13.8511838088 -23 23 00.897966240           ~ 1 0
19 2MASS J18005639-2256080 * 18 00 56.40 -22 56 08.0           ~ 1 0
20 2MASS J18010311-2256514 * 18 01 03.1151852208 -22 56 51.491691636           ~ 1 0
21 2MASS J18011410-2249451 * 18 01 14.10 -22 49 45.1           ~ 1 0
22 2MASS J18011811-2247153 * 18 01 18.12 -22 47 15.3           ~ 1 0
23 2MASS J18012258-2302365 * 18 01 22.59 -23 02 36.6           ~ 1 0
24 2MASS J18014413-2257159 * 18 01 44.1328543896 -22 57 16.006983552           ~ 1 0
25 2MASS J18021397-2224235 * 18 02 13.97 -22 24 23.6           ~ 3 0
26 2MASS J18022444-2221300 * 18 02 24.4425069384 -22 21 30.116757744           ~ 1 0
27 2MASS J18022535-2240571 * 18 02 25.3655293896 -22 40 57.094811652           ~ 1 0
28 2MASS J18022714-2220094 HB* 18 02 27.15 -22 20 09.4           ~ 7 0
29 2MASS J18023368-2217377 RG* 18 02 33.6840177504 -22 17 37.824002088           ~ 8 0
30 2MASS J18024568-2224401 * 18 02 45.7370871672 -22 24 40.772651616           ~ 3 0
31 2MASS J18024927-2235330 LP? 18 02 49.2811079149 -22 35 33.070900405           ~ 2 0
32 2MASS J18025279-2209418 * 18 02 52.7786853456 -22 09 41.803344720           ~ 4 0
33 2MASS J18030869-2202255 * 18 03 08.69 -22 02 25.6           ~ 5 0
34 2MASS J18031249-2205261 * 18 03 12.5101345296 -22 05 26.337438996           ~ 5 0
35 2MASS J18031413-2200319 * 18 03 14.13 -22 00 32.0           ~ 3 0
36 2MASS J18031418-2201044 * 18 03 14.19 -22 01 04.4           ~ 1 0
37 2MASS J18031850-2158407 * 18 03 18.51 -21 58 40.8           ~ 3 0
38 2MASS J18032477-2156215 * 18 03 24.78 -21 56 21.5           ~ 5 0
39 2MASS J18033996-2150436 * 18 03 39.96 -21 50 43.6           ~ 2 0
40 2MASS J18041390-2136544 * 18 04 13.8984804456 -21 36 54.400122144           ~ 5 0
41 2MASS J18043299-2128594 * 18 04 33.0086293008 -21 28 59.497926204           ~ 1 0
42 NGC 6528 GlC 18 04 49.61 -30 03 20.8   12.12 10.65     ~ 524 0
43 2MASS J18050279-2116478 * 18 05 02.80 -21 16 47.9           ~ 1 0
44 2MASS J18050488-2115356 * 18 05 04.88 -21 15 35.7           ~ 1 0
45 2MASS J18052131-2123285 * 18 05 21.31 -21 23 28.6           ~ 1 0
46 2MASS J18052146-2113072 * 18 05 21.46 -21 13 07.3           ~ 1 0
47 2MASS J18052360-2113550 LP* 18 05 23.6037933408 -21 13 55.049490120           ~ 2 0
48 2MASS J18053645-2101391 * 18 05 36.4589068176 -21 01 39.166747500           ~ 1 0
49 2MASS J18054167-2103222 * 18 05 41.6712034248 -21 03 22.244746752           ~ 1 0
50 2MASS J18054264-2133137 * 18 05 42.65 -21 33 13.8           ~ 1 0
51 2MASS J18055113-2054081 * 18 05 51.1362137592 -20 54 08.209006308           ~ 1 0
52 2MASS J18055162-2058497 * 18 05 51.63 -20 58 49.8           ~ 1 0
53 2MASS J18055531-2054291 * 18 05 55.3212299256 -20 54 29.133088416           ~ 1 0
54 2MASS J18060082-2054329 * 18 06 00.83 -20 54 33.0           ~ 1 0
55 2MASS J18062106-2057205 * 18 06 21.06 -20 57 20.6           ~ 1 0
56 2MASS J18062277-2042426 * 18 06 22.78 -20 42 42.6           ~ 1 0
57 2MASS J18062848-2046313 * 18 06 28.48 -20 46 31.3           ~ 1 0
58 2MASS J18063737-2037075 * 18 06 37.37 -20 37 07.5           ~ 1 0
59 2MASS J18063761-2036328 * 18 06 37.61 -20 36 32.9           ~ 1 0
60 2MASS J18070259-2026152 * 18 07 02.60 -20 26 15.2           ~ 1 0
61 2MASS J18070979-2019469 * 18 07 09.79 -20 19 46.9           ~ 1 0
62 2MASS J18071519-2019115 * 18 07 15.19 -20 19 11.6           ~ 1 0
63 2MASS J18072347-2020383 * 18 07 23.4791088816 -20 20 38.310023364           ~ 1 0
64 2MASS J18074503-2013123 * 18 07 45.0368661576 -20 13 12.333552744           ~ 1 0
65 2MASS J18074768-2010555 * 18 07 47.6841202704 -20 10 55.551619488           ~ 1 0
66 2MASS J18075004-2009124 * 18 07 50.0429486640 -20 09 12.474069588           ~ 1 0
67 2MASS J18075072-2004092 * 18 07 50.72 -20 04 09.2           ~ 2 0
68 2MASS J18080357-2012390 * 18 08 03.5774753688 -20 12 39.053467116           ~ 1 0
69 2MASS J18080369-2012183 * 18 08 03.6915658704 -20 12 18.262077156           ~ 1 0
70 2MASS J18081169-1957043 * 18 08 11.70 -19 57 04.4           ~ 1 0
71 2MASS J18083365-1951190 * 18 08 33.66 -19 51 19.1           ~ 1 0
72 2MASS J18083443-1951257 * 18 08 34.4316163176 -19 51 25.716806820           ~ 1 0
73 2MASS J18083734-1950053 * 18 08 37.35 -19 50 05.3           ~ 2 0
74 2MASS J18085266-1943208 * 18 08 52.66 -19 43 20.9           ~ 1 0
75 2MASS J18085404-1946140 * 18 08 54.05 -19 46 14.1           ~ 1 0
76 NGC 6553 GlC 18 09 15.68 -25 54 27.9   9.08       ~ 600 0
77 2MASS J18092144-1930563 * 18 09 21.4453539768 -19 30 56.431923228           ~ 1 0
78 2MASS J18093749-1928271 * 18 09 37.50 -19 28 27.1           ~ 2 0
79 2MASS J18100632-1913573 * 18 10 06.3209618232 -19 13 57.421349328           ~ 1 0
80 2MASS J18102557-1904026 LP? 18 10 25.5731589000 -19 04 02.627243040           ~ 2 0
81 2MASS J18102787-1903561 * 18 10 27.8674565904 -19 03 56.260059444           ~ 1 0
82 2MASS J18104052-1854416 * 18 10 40.53 -18 54 41.6           ~ 4 0
83 2MASS J18105013-1854098 * 18 10 50.14 -18 54 09.9           ~ 2 0
84 2MASS J18105578-1846048 * 18 10 55.78 -18 46 04.9           M-0.9 4 0
85 2MASS J18105899-1848391 * 18 10 58.99 -18 48 39.2           ~ 2 0
86 2MASS J18113079-1830441 * 18 11 30.7875471432 -18 30 44.210327868           ~ 3 0
87 2MASS J18113791-1859364 * 18 11 37.92 -18 59 36.5           ~ 2 0
88 2MASS J18114716-1823424 * 18 11 47.1664637496 -18 23 42.463134276           ~ 4 0
89 2MASS J18114807-1849060 * 18 11 48.0711301176 -18 49 06.151150416           ~ 3 0
90 2MASS J18115557-1852075 * 18 11 55.5496493880 -18 52 08.207662944           ~ 2 0
91 2MASS J18115611-1852219 * 18 11 56.1098388360 -18 52 22.282367016           ~ 1 0
92 2MASS J18115931-1818273 * 18 11 59.31 -18 18 27.4           ~ 2 0
93 2MASS J18122379-1807581 * 18 12 23.8016434296 -18 07 58.296384660           ~ 4 0
94 2MASS J18122901-1813177 * 18 12 29.0101120272 -18 13 17.824273536           ~ 5 0
95 2MASS J18131679-1800492 * 18 13 16.79 -18 00 49.2           ~ 1 0
96 2MASS J18133249-1754349 * 18 13 32.4972740808 -17 54 34.898590800           ~ 1 0
97 2MASS J18135479-1745020 * 18 13 54.7957936992 -17 45 02.192736708           ~ 1 0
98 2MASS J18142154-1728594 * 18 14 21.54 -17 28 59.4           ~ 1 0
99 2MASS J18142934-1722525 * 18 14 29.3372515920 -17 22 52.520080260           ~ 1 0
100 2MASS J18144757-1705506 * 18 14 47.58 -17 05 50.6           ~ 2 0
101 2MASS J18145309-1700513 * 18 14 53.10 -17 00 51.3           ~ 2 0
102 2MASS J18152890-1653035 * 18 15 28.8981028848 -16 53 03.636582180           M0.2 5 0
103 2MASS J18153361-1654590 * 18 15 33.61 -16 54 59.1           ~ 3 0
104 2MASS J18155309-1643333 * 18 15 53.09 -16 43 33.3           ~ 3 0
105 2MASS J18155792-1635122 * 18 15 57.92 -16 35 12.2           ~ 4 0
106 2MASS J18160257-1644414 RG* 18 16 02.5767349392 -16 44 41.456412600           ~ 7 0
107 2MASS J18160672-1644414 * 18 16 06.73 -16 44 41.4           ~ 1 0
108 2MASS J18161429-1634092 * 18 16 14.2867583208 -16 34 09.293667276           ~ 3 0
109 2MASS J18161453-1637136 * 18 16 14.53 -16 37 13.6           ~ 3 0
110 2MASS J18161699-1633055 * 18 16 16.9944199176 -16 33 05.458817772           M-1.2 5 0
111 2MASS J18161836-1631589 * 18 16 18.37 -16 31 58.9           ~ 1 0
112 2MASS J18162017-1631323 * 18 16 20.18 -16 31 32.3           ~ 5 0
113 AP J18162196-1624191 LP? 18 16 21.9615090136 -16 24 19.122766233           ~ 5 0
114 2MASS J18162375-1621339 * 18 16 23.75 -16 21 33.9           ~ 4 0
115 2MASS J18162635-1628349 * 18 16 26.3625018360 -16 28 34.934687796           ~ 4 0
116 2MASS J18162644-1627395 * 18 16 26.45 -16 27 39.5           ~ 1 0
117 2MASS J18162673-1628432 * 18 16 26.7296317368 -16 28 43.205054556           ~ 1 0
118 2MASS J18163033-1626564 * 18 16 30.34 -16 26 56.5           ~ 2 0
119 2MASS J18163058-1625576 * 18 16 30.59 -16 25 57.6           ~ 1 0
120 2MASS J18163094-1635188 * 18 16 30.94 -16 35 18.8           ~ 2 0
121 2MASS J18163446-1625156 * 18 16 34.46 -16 25 15.7           ~ 3 0
122 2MASS J18163483-1632399 * 18 16 34.84 -16 32 39.9           ~ 4 0
123 2MASS J18163599-1622209 RG* 18 16 35.9928564360 -16 22 20.925720228           ~ 7 0
124 2MASS J18163719-1623371 * 18 16 37.20 -16 23 37.1           ~ 4 0
125 2MASS J18163818-1623339 * 18 16 38.18 -16 23 34.0           ~ 2 0
126 2MASS J18163898-1622558 * 18 16 38.9888126880 -16 22 55.793186436           ~ 1 0
127 AP J18164117-1622495 LP? 18 16 41.1774128256 -16 22 49.569785184           ~ 4 0
128 2MASS J18164906-1618307 LP? 18 16 49.0601492520 -16 18 30.656530800           ~ 2 0
129 2MASS J18165596-1609543 LP? 18 16 55.9651952328 -16 09 54.315868356           ~ 3 0
130 2MASS J18170487-1611183 * 18 17 04.8794088192 -16 11 18.378367188           ~ 1 0
131 2MASS J18170774-1604089 * 18 17 07.74 -16 04 08.9           ~ 1 0
132 2MASS J18171403-1607585 * 18 17 14.0332113024 -16 07 58.627415748           ~ 1 0
133 2MASS J18171474-1607508 * 18 17 14.74 -16 07 50.8           ~ 1 0
134 2MASS J18171859-1604530 * 18 17 18.59 -16 04 53.0           ~ 1 0
135 2MASS J18172252-1606310 * 18 17 22.53 -16 06 31.0           ~ 1 0
136 2MASS J18172368-1556570 LP? 18 17 23.6902144926 -15 56 57.097519535           ~ 2 0
137 2MASS J18172656-1606442 * 18 17 26.57 -16 06 44.3           ~ 1 0
138 2MASS J18172666-1604598 * 18 17 26.6660278800 -16 04 59.821937220           ~ 1 0
139 2MASS J18172671-1601240 AB? 18 17 26.711 -16 01 24.08           ~ 2 0
140 2MASS J18172765-1604148 * 18 17 27.65 -16 04 14.9           ~ 1 0
141 2MASS J18173080-1600301 * 18 17 30.80 -16 00 30.1           ~ 1 0
142 2MASS J18173216-1559481 * 18 17 32.1624394656 -15 59 48.128552124           ~ 1 0
143 2MASS J18173282-1559000 * 18 17 32.83 -15 59 00.0           ~ 1 0
144 2MASS J18173599-1605469 * 18 17 35.9922336696 -16 05 47.039804304           ~ 1 0
145 2MASS J18173642-1608207 * 18 17 36.4310622312 -16 08 20.845017492           ~ 1 0
146 2MASS J18173663-1557569 * 18 17 36.6377725200 -15 57 56.929254156           ~ 1 0
147 2MASS J18173686-1606598 * 18 17 36.86 -16 06 59.8           ~ 1 0
148 2MASS J18174107-1555263 * 18 17 41.07 -15 55 26.4           ~ 1 0
149 2MASS J18174269-1554325 * 18 17 42.70 -15 54 32.5           ~ 1 0
150 2MASS J18175459-1542375 * 18 17 54.5914416480 -15 42 37.525273416           ~ 1 0
151 2MASS J18175651-1555168 LP? 18 17 56.5105899288 -15 55 16.809415068           ~ 2 0
152 2MASS J18175672-1556450 * 18 17 56.7180369528 -15 56 45.027695112           ~ 1 0
153 2MASS J18175816-1554556 * 18 17 58.17 -15 54 55.7           ~ 1 0
154 2MASS J18180044-1557584 * 18 18 00.45 -15 57 58.5           ~ 1 0
155 2MASS J18180530-1557193 * 18 18 05.3077720848 -15 57 19.398280104           ~ 2 0
156 2MASS J18180796-1558390 * 18 18 07.97 -15 58 39.0           ~ 1 0
157 2MASS J18182675-1538190 * 18 18 26.76 -15 38 19.1           ~ 1 0
158 2MASS J18190201-1515230 * 18 19 02.0145023376 -15 15 23.192266032           ~ 2 0
159 2MASS J18200726-1507128 * 18 20 07.26 -15 07 12.9           ~ 2 0
160 2MASS J18200736-1510049 LP? 18 20 07.3635099960 -15 10 04.988314524           ~ 4 0
161 2MASS J18201252-1445497 * 18 20 12.52 -14 45 49.8           ~ 3 0
162 2MASS J18205261-1427211 * 18 20 52.6151537136 -14 27 21.205950768           ~ 1 0
163 2MASS J18205411-1421454 * 18 20 54.1109603928 -14 21 45.450042192           ~ 1 0
164 2MASS J18205779-1443284 * 18 20 57.79 -14 43 28.4           ~ 2 0
165 2MASS J18210607-1427287 * 18 21 06.07 -14 27 28.7           ~ 1 0
166 2MASS J18212708-1411376 * 18 21 27.08 -14 11 37.7           ~ 1 0
167 2MASS J18225215-1333471 * 18 22 52.15 -13 33 47.1           ~ 4 0
168 2MASS J18225815-1332223 RG* 18 22 58.1613168264 -13 32 22.380280656           ~ 6 0
169 2MASS J18231507-1323525 RG* 18 23 15.0773750232 -13 23 52.633343292           ~ 6 0
170 2MASS J18231755-1347159 * 18 23 17.5534372056 -13 47 15.939524040           ~ 1 0
171 2MASS J18232376-1311593 * 18 23 23.76 -13 11 59.4           ~ 7 0
172 2MASS J18233872-1315183 * 18 23 38.7307132104 -13 15 18.426601440           ~ 1 0
173 2MASS J18234495-1317261 * 18 23 44.9585078064 -13 17 26.087006220           ~ 4 0
174 2MASS J18240298-1252319 * 18 24 02.99 -12 52 32.0           ~ 3 0
175 2MASS J18241202-1250018 * 18 24 12.0229832784 -12 50 01.918226940           ~ 3 0
176 2MASS J18241387-1248558 * 18 24 13.88 -12 48 55.9           ~ 1 0
177 2MASS J18241442-1252414 Mi* 18 24 14.4320690243 -12 52 41.508283850         15.884 ~ 4 0
178 2MASS J18242739-1242290 * 18 24 27.40 -12 42 29.0           ~ 1 0
179 2MASS J18242754-1242178 * 18 24 27.54 -12 42 17.9           ~ 1 0
180 2MASS J18243726-1254039 * 18 24 37.27 -12 54 04.0           ~ 1 0
181 2MASS J18244436-1254581 RG* 18 24 44.3614314120 -12 54 58.306390776           ~ 7 0
182 2MASS J18245640-1229461 * 18 24 56.4030024528 -12 29 46.151095020           ~ 1 0
183 2MASS J18250170-1225085 * 18 25 01.70 -12 25 08.6           ~ 1 0
184 2MASS J18250407-1226134 * 18 25 04.07 -12 26 13.5           ~ 1 0
185 2MASS J18250569-1230077 * 18 25 05.6933448816 -12 30 07.862552352           ~ 1 0
186 2MASS J18251119-1228401 * 18 25 11.20 -12 28 40.2           ~ 2 0
187 2MASS J18252691-1241445 * 18 25 26.9083512240 -12 41 44.553489720           ~ 1 0
188 2MASS J18254075-1209222 * 18 25 40.75 -12 09 22.3           ~ 1 0
189 2MASS J18254359-1214594 * 18 25 43.6418660136 -12 14 59.072827524           ~ 1 0
190 2MASS J18260338-1226537 * 18 26 03.3827829672 -12 26 53.885911020           ~ 1 0
191 2MASS J18261533-1153228 * 18 26 15.3629335680 -11 53 22.790719104           ~ 1 0
192 2MASS J18261635-1220343 * 18 26 16.3428029208 -12 20 34.427379408           ~ 1 0
193 AP J18273795-1115315 LP? 18 27 37.9518049536 -11 15 31.380071400           ~ 5 0
194 2MASS J18273907-1139230 LP? 18 27 39.0787511904 -11 39 22.871695140           ~ 3 0
195 2MASS J18273981-1114498 * 18 27 39.8433760104 -11 14 49.935441624           ~ 1 0
196 2MASS J18275326-1108402 * 18 27 53.2700301120 -11 08 40.277720148           ~ 5 0
197 2MASS J18280279-1104160 RG* 18 28 02.7962090088 -11 04 16.096276236           ~ 8 0
198 2MASS J18281217-1056493 LP? 18 28 12.1769010960 -10 56 49.327415808           ~ 2 0
199 2MASS J18282735-1108498 RG* 18 28 27.3575276424 -11 08 49.921668492           ~ 7 0
200 2MASS J18283509-1049058 LP? 18 28 35.0879580792 -10 49 05.900948328           ~ 2 0
201 [CTC2004] 202 * 18 28 43.56 -11 03 11.6           ~ 1 0
202 V* VV Cep s*r 21 56 39.1414963149 +63 37 31.981636440 7.03 6.65 4.90 3.19 1.85 M2Ibep+B2?ep_sh 449 0

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