Microlensing for non-experts Microlensing for non-experts

Philip YockPhilip Yock

13th Microlensing Workshop  Institut d'Astrophysique de Paris,

January 19, 20, 21, 2009

January 2009Cover story

“Race to Find Alien Planets”

Radial velocity, transits, Kepler- but nothing on microlensing!

Radial velocity and transit both Radial velocity and transit both conceptually simple conceptually simple

How to present microlensing simply?

1. Create strong gravitational field

2. Qualitative picture2. Qualitative picture

Einstein arcs slide around the ring when Amax >> 1 If a low-mass planet is close to the ring, it perturbs the arc as it passes by Width of perturbation equals ‘slide-by’ time Height of perturbation planet mass Height of perturbation (roughly) independent of Amax

Perturbations occur in the FWHM 24 hours

3. Demonstrate magnification maps3. Demonstrate magnification maps

4. Teaching exercises4. Teaching exercises

Liebes theoremUmin

Masses of the lenses

5. Use magnification maps5. Use magnification maps

Typical low resolution mapTypical low resolution map

Typical medium resolution mapTypical medium resolution map

Typical high resolution mapTypical high resolution map

Resolution adjustable Resolution adjustable

Typical star size

Typical track of source starTypical track of source star

Parallax correctionsParallax correctionsAndy Gould ApJ 606, 319 2004

Parallaxed trackParallaxed track

Beware the Moire effect!Beware the Moire effect!

Shoot more rays

SummarySummary

Microlensing beautiful, but quite Microlensing beautiful, but quite complicatedcomplicated

Demonstrations possible Demonstrations possible

Teaching exercises possibleTeaching exercises possible

Magnification maps conceptually clear, Magnification maps conceptually clear, versatile, if not fastest versatile, if not fastest

Proof - test subjectsProof - test subjects

Ian Bond, Christine Botzler, Sarah Ian Bond, Christine Botzler, Sarah Holderness, Yvette Perrott, Lydia Phillpott, Holderness, Yvette Perrott, Lydia Phillpott, Nick Rattenbury, Sarah Schoen, Eike van Nick Rattenbury, Sarah Schoen, Eike van Seggern, Petra TangSeggern, Petra Tang

Proof - test subjectsProof - test subjects

Ian Bond, Christine Botzler, Sarah Ian Bond, Christine Botzler, Sarah Holderness, Yvette Perrott, Lydia Phillpott, Holderness, Yvette Perrott, Lydia Phillpott, Nick Rattenbury, Sarah Schoen, Eike van Nick Rattenbury, Sarah Schoen, Eike van Seggern, Petra TangSeggern, Petra Tang

I couldn’t be happier

Petra Tang - MB07397Petra Tang - MB07397

Chi2

theta t0

Eike van Seggern – MB02033Eike van Seggern – MB02033

A&A 411, L493, 2003 439, 645 , 2005

Planet orbiting the binary lens?Planet orbiting the binary lens?

Sarah SchoenSarah Schoen

Plasma wakefield accelerationPlasma wakefield acceleration

New Scientist, Jan 2009 – “Desktop atom smashers New Scientist, Jan 2009 – “Desktop atom smashers could replace LHC”could replace LHC”

Analaogous to microlensing – uses naturally occurring Analaogous to microlensing – uses naturally occurring fields – electromagnetic, not gravitational fields – electromagnetic, not gravitational

Could measure the charge of the quarkCould measure the charge of the quark

Could test multi-muons from FermilabCould test multi-muons from Fermilab

40 GeV to 80 GeV, for $10, in one 40 GeV to 80 GeV, for $10, in one meter, riding a plasma wakefield meter, riding a plasma wakefield

Chan Joshi et al, Nature 445, 741-744 (2007)

Invitation Invitation – – JanuaryJanuary 2010 meeting2010 meeting

Auckland, New Zealand

Conference centreConference centre

Auckland harbourAuckland harbour

RaceRace

Piha Piha

Test plasma wakefield conceptTest plasma wakefield concept