1 Study of an adaptive Study of an adaptive optics system for the optics system for the astronomy in the astronomy in the visible visible Sandrine Thomas, Sandrine Thomas, A. Tokovinin, N. van der Bliek, B. Gregory, A. Tokovinin, N. van der Bliek, B. Gregory, R. Tighe, R. Cantarutti, P. Schurter, E. Mondaca, R. Tighe, R. Cantarutti, P. Schurter, E. Mondaca, D. Sprayberry D. Sprayberry Santa Cruz, Santa Cruz, 2nd of March 2nd of March 2006 2006
44
Embed
Study of an adaptive optics system for the astronomy in the visible
Study of an adaptive optics system for the astronomy in the visible. Sandrine Thomas, A. Tokovinin, N. van der Bliek, B. Gregory, R. Tighe, R. Cantarutti, P. Schurter, E. Mondaca, D. Sprayberry. Santa Cruz,. 2nd of March 2006. Outline. Limitations of classical AOs - PowerPoint PPT Presentation
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
1
Study of an adaptive Study of an adaptive optics system for the optics system for the
astronomy in the astronomy in the visiblevisible
Study of an adaptive Study of an adaptive optics system for the optics system for the
astronomy in the astronomy in the visiblevisible
Sandrine Thomas,Sandrine Thomas,A. Tokovinin, N. van der Bliek, B. Gregory, A. Tokovinin, N. van der Bliek, B. Gregory,
R. Tighe, R. Cantarutti, P. Schurter, E. Mondaca, D. R. Tighe, R. Cantarutti, P. Schurter, E. Mondaca, D. SprayberrySprayberry
Santa Cruz, Santa Cruz, 2nd of March2nd of March 2006 2006
2
OutlineOutlineOutlineOutline
Limitations of classical AOs Limitations of classical AOs GLAO technics GLAO technics (Ground Layer Adaptive Optics) (Ground Layer Adaptive Optics)
Description and performanceDescription and performance
Example of SAM Example of SAM (SOAR Adaptive Module)(SOAR Adaptive Module)
Physical simulation of the Physical simulation of the atmospherical turbulence atmospherical turbulence Different atmospherical Different atmospherical
conditions possibleconditions possibleDifferent speeds Different speeds Different sources: Different sources:
Diode lDiode laser, aser, LEDLED UV, UV, LEDLED white white
rr00 300 300 m m atat 633 nm 633 nmAdjustable Adjustable
Choice of the DMChoice of the DMChoice of the DMChoice of the DM
SimulatedSimulated
MeasureMeasuredd
Tests of the electrostatic mirror OKO79 Tests of the electrostatic mirror OKO79 from OKOTECH then of the bimorph miroir from OKOTECH then of the bimorph miroir BIM60 from CILAS:BIM60 from CILAS: Stroke and inter-actuators strokeStroke and inter-actuators stroke AberrationsAberrations Influence functions ….Influence functions ….
Reduction of noisy Reduction of noisy pixelspixels
Not robust at low fluxNot robust at low flux
Quad CellQuad Cell Robustness and good Robustness and good noise propagation at low noise propagation at low flux and high Nflux and high Nrr
Response coefficient to Response coefficient to adjust and difficult to adjust and difficult to estimateestimate
Non-linear, not precise Non-linear, not precise at high fluxat high flux
Weigthed Weigthed windowinwindowingg
Robustness and good Robustness and good noise propagation noise propagation
Response coefficient to Response coefficient to adjustadjust
CorrelatioCorrelationn
Independent from the Independent from the size and shape of the size and shape of the spotspot
Peak determinationPeak determination
Big calculation Big calculation
By adapting the parameters for each method, it is possible to By adapting the parameters for each method, it is possible to find the minimum error with the minimum of changes find the minimum error with the minimum of changes
30
ExampleExample 1: Planet Finder 1: Planet Finder ExampleExample 1: Planet Finder 1: Planet Finder
Adaptive optics wide FoV in the visible Adaptive optics wide FoV in the visible Study of the main components of SAMStudy of the main components of SAM
TurSim: Development et validation TurSim: Development et validation MD: Validation and test of 2 types of mirrorMD: Validation and test of 2 types of mirrorContribution to the optical designContribution to the optical designDevelopment and use of a prototype Development and use of a prototype
Theoretical study and simulation of a SH WFS: Theoretical study and simulation of a SH WFS: Definition of an error budgetDefinition of an error budgetComparison of different methods of spot positionComparison of different methods of spot positionDevelopment of analytical expressions Development of analytical expressions Application to different type of systemsApplication to different type of systems
34
Search for tertiary Search for tertiary companions to close companions to close spectroscopic binariesspectroscopic binaries
Search for tertiary Search for tertiary companions to close companions to close spectroscopic binariesspectroscopic binaries
HIP 48215
VLT4VLT4
In collaboration with A. Tokovinin, M. Sterzik, S. Udry
Tokovinin A., Thomas S., Sterzik M., Udry S., A&A, 2006
35
ContextContextContextContext
How do we explain the separation of How do we explain the separation of close binaries of a few days?close binaries of a few days?
Molecular cloudMolecular cloud
HowHow??
Accre
tion
Accre
tion
Close binariesClose binaries
Angular Angular momentumomentumm
37
Close binaries formation Close binaries formation Close binaries formation Close binaries formation IdeaIdea:: orbital shrinkageorbital shrinkageMagnetic breaking or disk breaking…Magnetic breaking or disk breaking…Evolution like Kozai cycle (Kozai 1962) Evolution like Kozai cycle (Kozai 1962)
Hypothesis: deposition of the angular momentum in Hypothesis: deposition of the angular momentum in a tertiary componenta tertiary component
Existence = Melo et al. 2001, SimulationExistence = Melo et al. 2001, Simulationss: Sterzik et al. 2003: Sterzik et al. 2003
qq1, 1,
PP11~10d~10d
qq3, 3, PP33~10~1044 yryr
Loi de Loi de Kepler’s :Kepler’s : M
P
a2
3
a = demi granda = demi grand--axeaxeq = rapport des massesq = rapport des massesP = période P = période
??
QuestionQuestion: : Are tertiaries Are tertiaries needed in the SBs needed in the SBs formation?formation?Are all SBs part of a Are all SBs part of a multiple system?multiple system?
Close < 100pc Close < 100pc (Hipparcos) larger (Hipparcos) larger separations separations
Periods [1Periods [1jj – 30 – 30jj] ] CORALIE, Batten et al. CORALIE, Batten et al. (1989), recent paper(1989), recent paper
DwarfsDwarfs from from 0.4 to 1.7 0.4 to 1.7
MM.. ( more numerous( more numerous,, close, not close, not
too bright and sharp lines.)too bright and sharp lines.)
SampleSample
HIP 279030pc, G8V
TechnicsTechnics
165 SBs in 161 systems165 SBs in 161 systems
39
NACO: AO on Yepun (VLT4)NACO: AO on Yepun (VLT4)NACO: AO on Yepun (VLT4)NACO: AO on Yepun (VLT4)
2 runs2 runs:: Novembre Novembre 2004 and July 20052004 and July 2005Band K + bands J H for Band K + bands J H for some of Nov.some of Nov.72 objects observed +72 objects observed +
2 calibrators2 calibrators
1pixel = 13.30 13.30 masmas
• NACO: Imagery, NACO: Imagery, polarimetry, spectroscopy, polarimetry, spectroscopy, coronography coronography • = 1= 1--5 5 m.m.• R ~ 50% in K band with a R ~ 50% in K band with a reference star of V=12 reference star of V=12
40
Example of companionsExample of companionsExample of companionsExample of companions
HIP 98578HIP 98578
1 = 3.70” 1 = 340K = 2.25
2 = 0.39”2 = 353K = 0.62
AA
BB
CC
= = SBSBRepresentative Representative narrow-band images narrow-band images FoV = 2’’ x 2’’FoV = 2’’ x 2’’
41
Data reductionData reductionData reductionData reductionRegular data reduction, package EclipseRegular data reduction, package EclipseDAOPHOT procedureDAOPHOT procedure:: fitting of the fitting of the image with the primary.image with the primary.PSF extractionPSF extraction
• Position error Position error = 0.5 mas if = 0.5 mas if m<3m<3mm and 5 mas if and 5 mas if m=5m=5mm
• rms magnitude difference error rms magnitude difference error = 0.02= 0.02mm if if m<3m<3mm and and 0.050.05mm if if m=5m=5mm
Period distributionPeriod distributionPeriod distributionPeriod distribution
BinariesBinariesTertiariesTertiaries
SBs with a tertiaires have a SBs with a tertiaires have a significatively significatively larger larger fraction of systems with fraction of systems with PP11<10<10dd
Tertiary fraction depends on the period PTertiary fraction depends on the period P11 of the SBsof the SBs– For PFor P11<3<3dd, almost all SBs , almost all SBs multiple systems multiple systems– If PIf P1 1 is bigger, is bigger, pure SBs. Tertiary frequency < pure SBs. Tertiary frequency <
one of solar type systemsone of solar type systems
Different period distribution between Different period distribution between triple and binariestriple and binariesSame mass distributionSame mass distribution
No relation between PNo relation between P11 and P and P33
Most massive component = closest one Most massive component = closest one pure SBs pure SBs no Kozai cycle no Kozai cycle
Hyp: accretion, Hyp: accretion, disk brakingdisk braking..
SBSBs s could have lost their could have lost their tertiariestertiaries..
49
PerspectivesPerspectivesPerspectivesPerspectives
Implementation of GLAO systems Implementation of GLAO systems 1st generation of AO for the ELTs1st generation of AO for the ELTsFollow-up of the WFS study in the case Follow-up of the WFS study in the case of a laser guide starof a laser guide star
Problem of SBs is only partially Problem of SBs is only partially resolvedresolvedOther science: Brown dwarf formation, Other science: Brown dwarf formation, Herbig AeBe star formation.Herbig AeBe star formation.
50MERCI A TOUSMERCI A TOUSMERCI A TOUSMERCI A TOUS