Potential direct single-star mass measurement

H  Ghosh; D L  DePoy; A  Gal-Yam; B S  Gaudi; A  Gould; C  Han; Y  Lipkin; D  Maoz; E O  Ofek; B G  Park; R W  Pogge; S  Salim; F  Abe; D P  Bennett; I A  Bond; S  Eguchi; Y  Furuta; J B  Hearnshaw; K  Kamiya; P M  Kilmartin; Y  Kurata; K  Masuda; Y  Matsubara; Y  Muraki; S  Noda; K  Okajima; N J  Rattenbury; T  Sako; T  Sekiguchi; D J  Sullivan; T  Sumi; P J  Tristram; T  Yanagisawa; P C M  Yock; A  Udalski; I  Soszynski; X  Wyrzykowski; M  Kubiak; M K  Szymanski; G  Pietrzynski; O  Szewczyk; K  Zebrun; M D  Albrow; J P  Beaulieu; J A R  Caldwell; A  Cassan; C  Coutures; M  Dominik; J  Donatowicz; P  Fouque; J  Greenhill; K  Hill; K  Horne; U G  Jorgensen; S  Kane; D  Kubas; R  Martin; J  Menzies; K R  Pollard; K C  Sahu; J  Wambsganss; R  Watson; A  Williams

Potential direct single-star mass measurement

H Ghosh, D L DePoy, A Gal-Yam, B S Gaudi, A Gould, C Han, Y Lipkin, D Maoz, E O Ofek, B G Park, R W Pogge, S Salim, F Abe, D P Bennett, I A Bond, S Eguchi, Y Furuta, J B Hearnshaw, K Kamiya, P M KilmartinY Kurata, K Masuda, Y Matsubara, Y Muraki, S Noda, K Okajima, N J Rattenbury, T Sako, T Sekiguchi, D J Sullivan, T Sumi, P J Tristram, T Yanagisawa, P C M Yock, A Udalski, I Soszynski, X Wyrzykowski, M Kubiak, M K Szymanski, G Pietrzynski, O Szewczyk, K Zebrun, M D Albrow, J P Beaulieu, J A R Caldwell, A Cassan, C Coutures, M Dominik, J Donatowicz, P Fouque, J Greenhill, K Hill, K Horne, U G Jorgensen, S Kane, D Kubas, R Martin, J Menzies, K R Pollard, K C Sahu, J Wambsganss, R Watson, A Williams

School of Physics and Astronomy

Research output: Contribution to journal › Article › peer-review

33 Citations (Scopus)

Abstract

We analyze the light curve of the microlensing event OGLE-2003-BLG-175/MOA-2003-BLG-45 and show that it has two properties that, when combined with future high-resolution astrometry, could lead to a direct, accurate measurement of the lens mass. First, the light curve shows clear signs of distortion due to the Earth's accelerated motion, which yields a measurement of the projected Einstein radius (r) over tilde (E). Second, from precise astrometric measurements, we show that the blended light in the event is coincident with the microlensed source to within about 15 mas. This argues strongly that this blended light is the lens and hence opens the possibility of directly measuring the lens-source relative proper motion mu(rel) and so the mass M=(c(2)/4G)mu(rel)t(E)(r) over tilde (E), where t(E) is the measured Einstein timescale. While the light-curve-based measurement of (r) over tildeE is, by itself, severely degenerate, we show that this degeneracy can be completely resolved by measuring the direction of proper motion mu(rel).

Original language	English
Pages (from-to)	450-459
Number of pages	10
Journal	Astrophysical Journal Letters
Volume	615
Publication status	Published - 1 Nov 2004

Keywords

astrometry
gravitational lensing
stars : fundamental parameters
GRAVITATIONAL LENSING EXPERIMENT
LARGE-MAGELLANIC-CLOUD
PARALLAX MICROLENS DEGENERACY
SPACE-INTERFEROMETRY-MISSION
DIFFERENCE IMAGE-ANALYSIS
GALACTIC BULGE
EVENT
HALO
EXTINCTION
PHOTOMETRY

Cite this

@article{93eb556ccaa348b7a94580ea6657b7c3,

title = "Potential direct single-star mass measurement",

abstract = "We analyze the light curve of the microlensing event OGLE-2003-BLG-175/MOA-2003-BLG-45 and show that it has two properties that, when combined with future high-resolution astrometry, could lead to a direct, accurate measurement of the lens mass. First, the light curve shows clear signs of distortion due to the Earth's accelerated motion, which yields a measurement of the projected Einstein radius (r) over tilde (E). Second, from precise astrometric measurements, we show that the blended light in the event is coincident with the microlensed source to within about 15 mas. This argues strongly that this blended light is the lens and hence opens the possibility of directly measuring the lens-source relative proper motion mu(rel) and so the mass M=(c(2)/4G)mu(rel)t(E)(r) over tilde (E), where t(E) is the measured Einstein timescale. While the light-curve-based measurement of (r) over tildeE is, by itself, severely degenerate, we show that this degeneracy can be completely resolved by measuring the direction of proper motion mu(rel).",

keywords = "astrometry, gravitational lensing, stars : fundamental parameters, GRAVITATIONAL LENSING EXPERIMENT, LARGE-MAGELLANIC-CLOUD, PARALLAX MICROLENS DEGENERACY, SPACE-INTERFEROMETRY-MISSION, DIFFERENCE IMAGE-ANALYSIS, GALACTIC BULGE, EVENT, HALO, EXTINCTION, PHOTOMETRY",

author = "H Ghosh and DePoy, {D L} and A Gal-Yam and Gaudi, {B S} and A Gould and C Han and Y Lipkin and D Maoz and Ofek, {E O} and Park, {B G} and Pogge, {R W} and S Salim and F Abe and Bennett, {D P} and Bond, {I A} and S Eguchi and Y Furuta and Hearnshaw, {J B} and K Kamiya and Kilmartin, {P M} and Y Kurata and K Masuda and Y Matsubara and Y Muraki and S Noda and K Okajima and Rattenbury, {N J} and T Sako and T Sekiguchi and Sullivan, {D J} and T Sumi and Tristram, {P J} and T Yanagisawa and Yock, {P C M} and A Udalski and I Soszynski and X Wyrzykowski and M Kubiak and Szymanski, {M K} and G Pietrzynski and O Szewczyk and K Zebrun and Albrow, {M D} and Beaulieu, {J P} and Caldwell, {J A R} and A Cassan and C Coutures and M Dominik and J Donatowicz and P Fouque and J Greenhill and K Hill and K Horne and Jorgensen, {U G} and S Kane and D Kubas and R Martin and J Menzies and Pollard, {K R} and Sahu, {K C} and J Wambsganss and R Watson and A Williams",

year = "2004",

month = nov,

day = "1",

language = "English",

volume = "615",

pages = "450--459",

journal = "Astrophysical Journal Letters",

issn = "2041-8205",

publisher = "American Astronomical Society",

}

Ghosh, H, DePoy, DL, Gal-Yam, A, Gaudi, BS, Gould, A, Han, C, Lipkin, Y, Maoz, D, Ofek, EO, Park, BG, Pogge, RW, Salim, S, Abe, F, Bennett, DP, Bond, IA, Eguchi, S, Furuta, Y, Hearnshaw, JB, Kamiya, K, Kilmartin, PM, Kurata, Y, Masuda, K, Matsubara, Y, Muraki, Y, Noda, S, Okajima, K, Rattenbury, NJ, Sako, T, Sekiguchi, T, Sullivan, DJ, Sumi, T, Tristram, PJ, Yanagisawa, T, Yock, PCM, Udalski, A, Soszynski, I, Wyrzykowski, X, Kubiak, M, Szymanski, MK, Pietrzynski, G, Szewczyk, O, Zebrun, K, Albrow, MD, Beaulieu, JP, Caldwell, JAR, Cassan, A, Coutures, C, Dominik, M, Donatowicz, J, Fouque, P, Greenhill, J, Hill, K, Horne, K, Jorgensen, UG, Kane, S, Kubas, D, Martin, R, Menzies, J, Pollard, KR, Sahu, KC, Wambsganss, J, Watson, R & Williams, A 2004, 'Potential direct single-star mass measurement', Astrophysical Journal Letters, vol. 615, pp. 450-459.

TY - JOUR

T1 - Potential direct single-star mass measurement

AU - Ghosh, H

AU - DePoy, D L

AU - Gal-Yam, A

AU - Gaudi, B S

AU - Gould, A

AU - Han, C

AU - Lipkin, Y

AU - Maoz, D

AU - Ofek, E O

AU - Park, B G

AU - Pogge, R W

AU - Salim, S

AU - Abe, F

AU - Bennett, D P

AU - Bond, I A

AU - Eguchi, S

AU - Furuta, Y

AU - Hearnshaw, J B

AU - Kamiya, K

AU - Kilmartin, P M

AU - Kurata, Y

AU - Masuda, K

AU - Matsubara, Y

AU - Muraki, Y

AU - Noda, S

AU - Okajima, K

AU - Rattenbury, N J

AU - Sako, T

AU - Sekiguchi, T

AU - Sullivan, D J

AU - Sumi, T

AU - Tristram, P J

AU - Yanagisawa, T

AU - Yock, P C M

AU - Udalski, A

AU - Soszynski, I

AU - Wyrzykowski, X

AU - Kubiak, M

AU - Szymanski, M K

AU - Pietrzynski, G

AU - Szewczyk, O

AU - Zebrun, K

AU - Albrow, M D

AU - Beaulieu, J P

AU - Caldwell, J A R

AU - Cassan, A

AU - Coutures, C

AU - Dominik, M

AU - Donatowicz, J

AU - Fouque, P

AU - Greenhill, J

AU - Hill, K

AU - Horne, K

AU - Jorgensen, U G

AU - Kane, S

AU - Kubas, D

AU - Martin, R

AU - Menzies, J

AU - Pollard, K R

AU - Sahu, K C

AU - Wambsganss, J

AU - Watson, R

AU - Williams, A

PY - 2004/11/1

Y1 - 2004/11/1

N2 - We analyze the light curve of the microlensing event OGLE-2003-BLG-175/MOA-2003-BLG-45 and show that it has two properties that, when combined with future high-resolution astrometry, could lead to a direct, accurate measurement of the lens mass. First, the light curve shows clear signs of distortion due to the Earth's accelerated motion, which yields a measurement of the projected Einstein radius (r) over tilde (E). Second, from precise astrometric measurements, we show that the blended light in the event is coincident with the microlensed source to within about 15 mas. This argues strongly that this blended light is the lens and hence opens the possibility of directly measuring the lens-source relative proper motion mu(rel) and so the mass M=(c(2)/4G)mu(rel)t(E)(r) over tilde (E), where t(E) is the measured Einstein timescale. While the light-curve-based measurement of (r) over tildeE is, by itself, severely degenerate, we show that this degeneracy can be completely resolved by measuring the direction of proper motion mu(rel).

AB - We analyze the light curve of the microlensing event OGLE-2003-BLG-175/MOA-2003-BLG-45 and show that it has two properties that, when combined with future high-resolution astrometry, could lead to a direct, accurate measurement of the lens mass. First, the light curve shows clear signs of distortion due to the Earth's accelerated motion, which yields a measurement of the projected Einstein radius (r) over tilde (E). Second, from precise astrometric measurements, we show that the blended light in the event is coincident with the microlensed source to within about 15 mas. This argues strongly that this blended light is the lens and hence opens the possibility of directly measuring the lens-source relative proper motion mu(rel) and so the mass M=(c(2)/4G)mu(rel)t(E)(r) over tilde (E), where t(E) is the measured Einstein timescale. While the light-curve-based measurement of (r) over tildeE is, by itself, severely degenerate, we show that this degeneracy can be completely resolved by measuring the direction of proper motion mu(rel).

KW - astrometry

KW - gravitational lensing

KW - stars : fundamental parameters

KW - GRAVITATIONAL LENSING EXPERIMENT

KW - LARGE-MAGELLANIC-CLOUD

KW - PARALLAX MICROLENS DEGENERACY

KW - SPACE-INTERFEROMETRY-MISSION

KW - DIFFERENCE IMAGE-ANALYSIS

KW - GALACTIC BULGE

KW - EVENT

KW - HALO

KW - EXTINCTION

KW - PHOTOMETRY

UR - http://www.scopus.com/inward/record.url?scp=10844281814&partnerID=8YFLogxK

M3 - Article

SN - 2041-8205

VL - 615

SP - 450

EP - 459

JO - Astrophysical Journal Letters

JF - Astrophysical Journal Letters

ER -

Potential direct single-star mass measurement

Abstract

Keywords

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