2011A&A...525A..15Z


Query : 2011A&A...525A..15Z

2011A&A...525A..15Z - Astronomy and Astrophysics, volume 525A, 15-15 (2011/1-1)

Limb-darkening measurements for a cool red giant in microlensing event OGLE 2004-BLG-482.

ZUB M., CASSAN A., HEYROVSKY D., FOUQUE P., STEMPELS H.C., ALBROW M.D., BEAULIEU J.-P., BRILLANT S., CHRISTIE G.W., KAINS N., KOZLOWSKI S., KUBAS D., WAMBSGANSS J., BATISTA V., BENNETT D.P., COOK K., COUTURES C., DIETERS S., DOMINIK M., DOMINIS PRESTER D., DONATOWICZ J., GREENHILL J., HORNE K., JORGENSEN U.G., KANE S.R., MARQUETTE J.-B., MARTIN R., MENZIES J., POLLARD K.R., SAHU K.C., VINTER C., WILLIAMS A., GOULD A., DEPOY D.L., GAL-YAM A., GAUDI B.S., HAN C., LIPKIN Y., MAOZ D., OFEK E.O., PARK B.-G., POGGE R.W., McCORMICK J., UDALSKI A., SZYMANSKI M.K., KUBIAK M., PIETRZYNSKI G., SOSZYNSKI I., SZEWCZYK O. and WYRZYKOWSKI L.

Abstract (from CDS):

We present a detailed analysis of OGLE 2004-BLG-482, a relatively high-magnification single-lens microlensing event that exhibits clear extended-source effects. These events are relatively rare, but they potentially contain unique information on the stellar atmosphere properties of their source star, as shown in this study. Our dense photometric coverage of the overall light curve and a proper microlensing modelling allow us to derive measurements of the OGLE 2004-BLG-482 source star's linear limb-darkening coefficients in three bands, including standard Johnson-Cousins I and R, as well as in a broad clear filter. In particular, we discuss in detail the problems of multi-band and multi-site modelling on the expected precision of our results. We also obtained high-resolution UVES spectra as part of a ToO programme at ESO VLT, from which we derive the source star's precise fundamental parameters. From the high-resolution UVES spectra, we find that OGLE 2004-BLG-482's source star is a red giant of MK type a bit later than M3, with Teff=3667±150K, logg=2.1±1.0 and an assumed solar metallicity. This is confirmed by an OGLE calibrated colour-magnitude diagram. We then obtain from a detailed microlensing modelling of the light curve linear limb-darkening coefficients that we compare to model-atmosphere predictions available in the literature, and find a very good agreement for the I and R bands. In addition, we perform a similar analysis using an alternative description of limb darkening based on a principal component analysis of ATLAS limb-darkening profiles, and also find a very good agreement between measurements and model predictions.

Abstract Copyright:

Journal keyword(s): gravitational lensing: micro - stars: atmospheres - techniques: high angular resolution - stars: individual: OGLE 2004-BLG-482

CDS comments: Paragraph.1 OGLE 2004-BLG-262 is a misprint for EWS 2003-BUL-262.

Simbad objects: 16

goto Full paper

goto View the references in ADS

Number of rows : 16
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 MACHO 208.15683.4237 * 00 45 35.3 -72 52 33           ~ 64 0
2 NAME SMC G 00 52 38.0 -72 48 01   2.79 2.2     ~ 11287 1
3 NAME Galactic Center reg 17 45 39.60213 -29 00 22.0000           ~ 14643 0
4 OGLE-2003-BUL-238 * 17 45 50.34 -22 40 58.1           K2III 12 0
5 OGLE-2002-BUL-069 * 17 48 01.00 -21 16 09.3           G5III 17 0
6 EROS BLG 2000 5 * 17 53 11.43 -30 55 34.4           K3III 36 0
7 MACHO 97-BLG-41 ** 17 56 20.7 -28 47 42           ~ 55 1
8 OGLE-2004-BUL-254 * 17 56 36.20 -32 33 01.8           K3III 5 0
9 OGLE-2003-BUL-262 * 17 57 08.51 -30 20 05.1           ~ 7 0
10 OGLE 2004-BUL-482 * 17 57 30.6268943160 -30 51 30.607919388         14.57 MIII 6 0
11 MOA 2002-BLG-33 * 17 58 24.60 -29 06 11.3           ~ 15 0
12 MACHO 97-BLG-28 * 18 00 33.9 -28 01 10     18.1     ~ 31 0
13 NAME Baade Window reg 18 03.5 -30 01           ~ 618 3
14 MACHO 95-BLG-30 * 18 07 04.4 -27 22 06     16.21     M4III 39 0
15 OGLE BUL-SC19 26606 * 18 07 45.14 -27 33 15.4           ~ 22 0
16 NAME Galactic Bulge reg ~ ~           ~ 4360 0

To bookmark this query, right click on this link: simbad:objects in 2011A&A...525A..15Z and select 'bookmark this link' or equivalent in the popup menu