A systematic fitting scheme for caustic-crossing microlensing events

N. Kains; A. Cassan; K. Horne; M. D. Albrow; S. Dieters; P. Fouque; J. Greenhill; A. Udalski; M. Zub; D. P. Bennett; Martin Dominik; J. Donatowicz; D. Kubas; Y. Tsapras; T. Anguita; V. Batista; J. -P. Beaulieu; S. Brillant; M. Bode; D. M. Bramich; M. Burgdorf; J. A. R. Caldwell; K. H. Cook; Ch. Coutures; D. Dominis Prester; U. G. Jorgensen; S. Kane; J. B. Marquette; R. Martin; J. Menzies; K. R. Pollard; N. Rattenbury; K. C. Sahu; C. Snodgrass; I. Steele; C. Vinter; J. Wambsganss; A. Williams; M. Kubiak; G. Pietrzynski; I. Soszynski; O. Szewczyk; M. K. Szymanski; K. Ulaczyk; L. Wyrzykowski

doi:10.1111/j.1365-2966.2009.14615.x

A systematic fitting scheme for caustic-crossing microlensing events

N. Kains, A. Cassan, K. Horne, M. D. Albrow, S. Dieters, P. Fouque, J. Greenhill, A. Udalski, M. Zub, D. P. Bennett, Martin Dominik, J. Donatowicz, D. Kubas, Y. Tsapras, T. Anguita, V. Batista, J. -P. Beaulieu, S. Brillant, M. Bode, D. M. BramichM. Burgdorf, J. A. R. Caldwell, K. H. Cook, Ch. Coutures, D. Dominis Prester, U. G. Jorgensen, S. Kane, J. B. Marquette, R. Martin, J. Menzies, K. R. Pollard, N. Rattenbury, K. C. Sahu, C. Snodgrass, I. Steele, C. Vinter, J. Wambsganss, A. Williams, M. Kubiak, G. Pietrzynski, I. Soszynski, O. Szewczyk, M. K. Szymanski, K. Ulaczyk, L. Wyrzykowski

School of Physics and Astronomy

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

Abstract

We outline a method for fitting binary-lens caustic-crossing microlensing events based on the alternative model parametrization proposed and detailed by Cassan. As an illustration of our methodology, we present an analysis of OGLE-2007-BLG-472, a double-peaked Galactic microlensing event with a source crossing the whole caustic structure in less than three days. In order to identify all possible models we conduct an extensive search of the parameter space, followed by a refinement of the parameters with a Markov Chain Monte Carlo algorithm. We find a number of low-chi(2) regions in the parameter space, which lead to several distinct competitive best models. We examine the parameters for each of them, and estimate their physical properties. We find that our fitting strategy locates several minima that are difficult to find with other modelling strategies and is therefore a more appropriate method to fit this type of event.

Original language	English
Pages (from-to)	787-796
Number of pages	10
Journal	Monthly Notices of the Royal Astronomical Society
Volume	395
Issue number	2
DOIs	https://doi.org/10.1111/j.1365-2966.2009.14615.x
Publication status	Published - 11 May 2009

Keywords

gravitational lensing
methods: miscellaneous
binaries: general
planetary systems
Galaxy: bulge
INITIAL MASS FUNCTION
GRAVITATIONAL LENS
GALACTIC BULGE
STARS
LUMINOSITY

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10.1111/j.1365-2966.2009.14615.x

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Kains, N., Cassan, A., Horne, K., Albrow, M. D., Dieters, S., Fouque, P., Greenhill, J., Udalski, A., Zub, M., Bennett, D. P., Dominik, M., Donatowicz, J., Kubas, D., Tsapras, Y., Anguita, T., Batista, V., Beaulieu, J. .-P., Brillant, S., Bode, M., ... Wyrzykowski, L. (2009). A systematic fitting scheme for caustic-crossing microlensing events. Monthly Notices of the Royal Astronomical Society, 395(2), 787-796. https://doi.org/10.1111/j.1365-2966.2009.14615.x

@article{0c15780cc88e407bbe085131ad1a4349,

title = "A systematic fitting scheme for caustic-crossing microlensing events",

abstract = "We outline a method for fitting binary-lens caustic-crossing microlensing events based on the alternative model parametrization proposed and detailed by Cassan. As an illustration of our methodology, we present an analysis of OGLE-2007-BLG-472, a double-peaked Galactic microlensing event with a source crossing the whole caustic structure in less than three days. In order to identify all possible models we conduct an extensive search of the parameter space, followed by a refinement of the parameters with a Markov Chain Monte Carlo algorithm. We find a number of low-chi(2) regions in the parameter space, which lead to several distinct competitive best models. We examine the parameters for each of them, and estimate their physical properties. We find that our fitting strategy locates several minima that are difficult to find with other modelling strategies and is therefore a more appropriate method to fit this type of event.",

keywords = "gravitational lensing, methods: miscellaneous, binaries: general, planetary systems, Galaxy: bulge, INITIAL MASS FUNCTION, GRAVITATIONAL LENS, GALACTIC BULGE, STARS, LUMINOSITY",

author = "N. Kains and A. Cassan and K. Horne and Albrow, {M. D.} and S. Dieters and P. Fouque and J. Greenhill and A. Udalski and M. Zub and Bennett, {D. P.} and Martin Dominik and J. Donatowicz and D. Kubas and Y. Tsapras and T. Anguita and V. Batista and Beaulieu, {J. -P.} and S. Brillant and M. Bode and Bramich, {D. M.} and M. Burgdorf and Caldwell, {J. A. R.} and Cook, {K. H.} and Ch. Coutures and Prester, {D. Dominis} and Jorgensen, {U. G.} and S. Kane and Marquette, {J. B.} and R. Martin and J. Menzies and Pollard, {K. R.} and N. Rattenbury and Sahu, {K. C.} and C. Snodgrass and I. Steele and C. Vinter and J. Wambsganss and A. Williams and M. Kubiak and G. Pietrzynski and I. Soszynski and O. Szewczyk and Szymanski, {M. K.} and K. Ulaczyk and L. Wyrzykowski",

year = "2009",

month = may,

day = "11",

doi = "10.1111/j.1365-2966.2009.14615.x",

language = "English",

volume = "395",

pages = "787--796",

journal = "Monthly Notices of the Royal Astronomical Society",

issn = "0035-8711",

publisher = "Oxford University Press",

number = "2",

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Kains, N, Cassan, A, Horne, K, Albrow, MD, Dieters, S, Fouque, P, Greenhill, J, Udalski, A, Zub, M, Bennett, DP, Dominik, M, Donatowicz, J, Kubas, D, Tsapras, Y, Anguita, T, Batista, V, Beaulieu, J-P, Brillant, S, Bode, M, Bramich, DM, Burgdorf, M, Caldwell, JAR, Cook, KH, Coutures, C, Prester, DD, Jorgensen, UG, Kane, S, Marquette, JB, Martin, R, Menzies, J, Pollard, KR, Rattenbury, N, Sahu, KC, Snodgrass, C, Steele, I, Vinter, C, Wambsganss, J, Williams, A, Kubiak, M, Pietrzynski, G, Soszynski, I, Szewczyk, O, Szymanski, MK, Ulaczyk, K & Wyrzykowski, L 2009, 'A systematic fitting scheme for caustic-crossing microlensing events', Monthly Notices of the Royal Astronomical Society, vol. 395, no. 2, pp. 787-796. https://doi.org/10.1111/j.1365-2966.2009.14615.x

TY - JOUR

T1 - A systematic fitting scheme for caustic-crossing microlensing events

AU - Kains, N.

AU - Cassan, A.

AU - Horne, K.

AU - Albrow, M. D.

AU - Dieters, S.

AU - Fouque, P.

AU - Greenhill, J.

AU - Udalski, A.

AU - Zub, M.

AU - Bennett, D. P.

AU - Dominik, Martin

AU - Donatowicz, J.

AU - Kubas, D.

AU - Tsapras, Y.

AU - Anguita, T.

AU - Batista, V.

AU - Beaulieu, J. -P.

AU - Brillant, S.

AU - Bode, M.

AU - Bramich, D. M.

AU - Burgdorf, M.

AU - Caldwell, J. A. R.

AU - Cook, K. H.

AU - Coutures, Ch.

AU - Prester, D. Dominis

AU - Jorgensen, U. G.

AU - Kane, S.

AU - Marquette, J. B.

AU - Martin, R.

AU - Menzies, J.

AU - Pollard, K. R.

AU - Rattenbury, N.

AU - Sahu, K. C.

AU - Snodgrass, C.

AU - Steele, I.

AU - Vinter, C.

AU - Wambsganss, J.

AU - Williams, A.

AU - Kubiak, M.

AU - Pietrzynski, G.

AU - Soszynski, I.

AU - Szewczyk, O.

AU - Szymanski, M. K.

AU - Ulaczyk, K.

AU - Wyrzykowski, L.

PY - 2009/5/11

Y1 - 2009/5/11

N2 - We outline a method for fitting binary-lens caustic-crossing microlensing events based on the alternative model parametrization proposed and detailed by Cassan. As an illustration of our methodology, we present an analysis of OGLE-2007-BLG-472, a double-peaked Galactic microlensing event with a source crossing the whole caustic structure in less than three days. In order to identify all possible models we conduct an extensive search of the parameter space, followed by a refinement of the parameters with a Markov Chain Monte Carlo algorithm. We find a number of low-chi(2) regions in the parameter space, which lead to several distinct competitive best models. We examine the parameters for each of them, and estimate their physical properties. We find that our fitting strategy locates several minima that are difficult to find with other modelling strategies and is therefore a more appropriate method to fit this type of event.

AB - We outline a method for fitting binary-lens caustic-crossing microlensing events based on the alternative model parametrization proposed and detailed by Cassan. As an illustration of our methodology, we present an analysis of OGLE-2007-BLG-472, a double-peaked Galactic microlensing event with a source crossing the whole caustic structure in less than three days. In order to identify all possible models we conduct an extensive search of the parameter space, followed by a refinement of the parameters with a Markov Chain Monte Carlo algorithm. We find a number of low-chi(2) regions in the parameter space, which lead to several distinct competitive best models. We examine the parameters for each of them, and estimate their physical properties. We find that our fitting strategy locates several minima that are difficult to find with other modelling strategies and is therefore a more appropriate method to fit this type of event.

KW - gravitational lensing

KW - methods: miscellaneous

KW - binaries: general

KW - planetary systems

KW - Galaxy: bulge

KW - INITIAL MASS FUNCTION

KW - GRAVITATIONAL LENS

KW - GALACTIC BULGE

KW - STARS

KW - LUMINOSITY

UR - http://www.scopus.com/inward/record.url?scp=65349166306&partnerID=8YFLogxK

U2 - 10.1111/j.1365-2966.2009.14615.x

DO - 10.1111/j.1365-2966.2009.14615.x

M3 - Article

SN - 0035-8711

VL - 395

SP - 787

EP - 796

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

IS - 2

ER -

A systematic fitting scheme for caustic-crossing microlensing events

Abstract

Keywords

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Astrophysics in St Andrews: Astrophysics in St Andrews / SUPA (Continuan of Rolling Grant - XPP089

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A systematic fitting scheme for caustic-crossing microlensing events

Abstract

Keywords

Access to Document

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Projects

Astrophysics in St Andrews: Astrophysics in St Andrews / SUPA (Continuan of Rolling Grant - XPP089

Astrophysics at St Andrews: Astrophysics at St.Andrews

Cite this