J/AcA/51/175 OGLE-II DIA microlensing events (Wozniak+, 2001)
Difference Image Analysis of the OGLE-II bulge data. II. Microlensing events.
Wozniak P.R., Udalski A., Szymanski M., Kubiak M., Pietrzynski G.,
Soszynski I., Zebrun K.
<Acta Astron., 51, 175 (2001)>
=2001AcA....51..175W 2001AcA....51..175W
ADC_Keywords: Gravitational lensing
Keywords: gravitational lensing - dark matter - Galaxy: center - catalogs
Abstract:
We present a sample of microlensing events discovered in the
Difference Image Analysis (DIA) of the OGLE-II images collected during
three observing seasons, 1997-1999. 4424 light curves pass our
criteria on the presence of a brightening episode on top of a constant
baseline. Among those, 512 candidate microlensing events were selected
visually. We designed an automated procedure, which unambiguously
selects up to 237 best events. Including eight candidate events
recovered by other means, a total of 520 light curves are presented in
this work.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
crossid.dat 30 520 DIA-OGLE corresponding numbers
table1.dat 47 49 OGLE-II bulge fields
tablesa.dat 70 520 All microlensing events, positions
tablesb.dat 68 520 All microlensing events, parameters
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See also:
J/A+A/313/841 : MACHO LMC No.1 microlensing event (Dominik+, 1996)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [bul_]
5- 8 A4 --- Field Field number (scNN)
10- 11 I2 h RAh Right ascension (J2000)
13- 14 I2 min RAm Right ascension (J2000)
16- 19 F4.1 s RAs Right ascension (J2000)
21 A1 --- DE- Declination sign (J2000)
22- 23 I2 deg DEd Declination (J2000)
25- 26 I2 arcmin DEm Declination (J2000)
28- 29 I2 arcsec DEs Declination (J2000)
31- 36 F6.2 deg GLON [-12/11] Galactic longitude
38- 42 F5.2 deg GLAT Galactic latitude
45- 47 I3 --- Nobs Number of observations
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Byte-by-byte Description of file: crossid.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Field Field number (SCNN)
9- 12 I4 --- DIA DIA star number in the field
17- 22 I6 --- OGLE ? OGLE number
26- 30 F5.3 pix Dist ? Distance between identified positions (1pix=0.4")
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Byte-by-byte Description of file: table?a.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Field Field designation (scNN)
6- 9 I4 --- DIA DIA star number in the field (1)
11- 17 F7.2 pix Xpos X position (2)
19- 25 F7.2 pix Ypos Y position (2)
27- 28 I2 h RAh Right ascension (J2000)
30- 31 I2 min RAm Right ascension (J2000)
33- 37 F5.2 s RAs Right ascension (J2000)
39 A1 --- DE- Declination sign (J2000)
40- 41 I2 deg DEd Declination (J2000)
43- 44 I2 arcmin DEm Declination (J2000)
46- 49 F4.1 arcsec DEs Declination (J2000)
51- 54 F4.2 --- Dist1 Centroid distance between the variable and
the nearest object on the reference frame
detected with DoPhot
56- 62 F7.2 --- Flux1 Flux of the nearest star on the reference frame
64- 68 F5.2 mag m(OGLE) Zero point offset between DIA fluxes and OGLE
database (varies with X, Y)
m(OGLE)=m(Zero)-2.5*log(flux)
70 A1 --- Det [234] Flag for detection method (3)
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Note (1): Number in the database of candidate variable objects from DIA
Note (2): 0.0 for the center of the pixel in lower left corner
Note (3): Method of detection as follows:
2 = Microlensing events found in the algorithmic search
3 = Microlensing events recovered in the visual search
4 = Events recovered by cross identification with the OGLE catalog
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Byte-by-byte Description of file: table?b.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- Field Field number (scNN)
6- 9 I4 --- DIA DIA star number in the field
11- 18 F8.2 --- F0 Baseline difference flux
20- 27 F8.2 --- F1 Lensed flux
29- 35 F7.5 --- u0 Impact parameter (units of Einstein radius)
37- 43 F7.2 s t0 Einstein ring crossing time
45- 51 F7.2 d tmax Moment of maximum light (HJD-2450000)
53 A1 --- l_I0 Limit flag on I0
54- 59 F6.3 mag I0 Baseline I magnitude
61- 68 F8.3 --- f Ratio of the lensed flux to the total baseline flux
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History:
Copied at http://astro.Princeton.EDU/~wozniak/dia/lens/
References:
Wozniak, Paper I 2000AcA....50..421W 2000AcA....50..421W
Smith et al., 2002MNRAS.332..962S 2002MNRAS.332..962S
(End) Patricia Bauer [CDS] 12-Nov-2002