automated fitting of high-resolution spectra of haebe stars improving fundamental parameters jason...
TRANSCRIPT
Automated Fitting Automated Fitting of High-Resolution of High-Resolution Spectra of HAeBe Spectra of HAeBe
starsstarsImproving fundamental Improving fundamental parametersparameters
Jason GrunhutJason GrunhutQueen’s University/RMCQueen’s University/RMC
MotivationMotivation Common ways to Common ways to
determine temperaturedetermine temperature PhotometryPhotometry SEDSED
ProblemsProblems Extinction/emission and Extinction/emission and
calibrationscalibrations Many corrections necessaryMany corrections necessary
Take advantage of high-res Take advantage of high-res ESPaDOnS spectraESPaDOnS spectra Minimal corrections requiredMinimal corrections required
Full ESPaDOnS Spectral Range Full ESPaDOnS Spectral Range 11000 K synthetic model11000 K synthetic model
Full ESPaDOnS Spectral Range Full ESPaDOnS Spectral Range 11000 K synthetic model11000 K synthetic model
Spectrum variation with temperature Spectrum variation with temperature from nearest Kurucz models (from nearest Kurucz models (±500 K)±500 K)
Spectrum variation with temperature Spectrum variation with temperature from nearest Kurucz models (from nearest Kurucz models (±500 K)±500 K)
Automated Fitting of Automated Fitting of SpectraSpectra
Search through a pre-defined grid of Search through a pre-defined grid of synthetic spectra.synthetic spectra. 4200-5200 Angstroms4200-5200 Angstroms Solar abundances.Solar abundances. Most current VALD line list.Most current VALD line list. Micro-turbulent velocity of 2 km/s.Micro-turbulent velocity of 2 km/s. No macro-turbulence.No macro-turbulence. Models computed using synth3Models computed using synth3 Grid from 6500-35000 K, log(g) from Grid from 6500-35000 K, log(g) from
3.0-5.03.0-5.0 100 K resolution up to 20000 K, 200 K 100 K resolution up to 20000 K, 200 K
resolution from then up.resolution from then up.
How Program WorksHow Program Works
Radial velocity is first determined Radial velocity is first determined based on suggested model.based on suggested model.
Projected rotational velocity is fit for Projected rotational velocity is fit for each model in the specified range each model in the specified range (computed using slightly modified (computed using slightly modified s3dIV code).s3dIV code).
Model with minimum chi-square Model with minimum chi-square represents best fit.represents best fit.
Radial velocity is fit for a final time Radial velocity is fit for a final time for best model.for best model.
Theoretical Results for Theoretical Results for 11000 K synthetic model 11000 K synthetic model
with vsini of with vsini of 40 km/s40 km/s
CLEAR MINIMUM
EXISTS
Chi-Square MapChi-Square MapHD 17081HD 17081
• Using chi-square map, can estimate uncertainties.
• Using 3 parameter fitting space, chi-square difference of 21.1 represents a formal 99.99% confidence level.
• closest model has greater than 2300 chi-square difference
Theoretical ResultsTheoretical Results
• Investigated
• SNR
• vsini
• varying Fe abundance
• random noise to log(gf) values
• micro/macro turbulence
• binaries
• normalization
• conclusion
• other than binaries, for reasonable variations, ~100-200 K uncertainties
ResultsResultsNameName Metallic Metallic
LinesLines(Teff, (Teff,
Log(g))Log(g))
ReducReduced ed χχ22
HHγγ(Teff, Log(g))(Teff, Log(g))
HHββ(Teff, (Teff,
Log(g))Log(g))
Literature Literature
ValueValue
HD HD 142666142666
7700, 4.07700, 4.0 6.686.68 7300, 3.57300, 3.5 7500, 4.57500, 4.5 85008500
HD HD 144432144432
7700, 4.07700, 4.0 7.167.16 7200, 3.07200, 3.0 7400, 4.57400, 4.5 79507950
HD 17081HD 17081 13700, 13700, 4.04.0
6.216.21 11800, 3.511800, 3.5 12000, 12000, 4.04.0
1230012300
HD HD 244604244604
8600, 3.58600, 3.5 5.295.29 8200, 4.08200, 4.0 8100, 4.08100, 4.0 ~9500~9500
HD 31648HD 31648 8200, 3.58200, 3.5 25.7725.77 8300, 4.08300, 4.0 8300, 4.08300, 4.0 8700 8700 ± ± 10051005
HD 34282HD 34282 10200, 10200, 4.54.5
2.232.23 9800, 4.59800, 4.5 10100, 10100, 4.54.5
8700 8700 +410/-198+410/-198
HD 35187HD 35187 9200, 4.09200, 4.0 4.664.66 8700, 4.08700, 4.0 8600, 4.08600, 4.0 9100 9100 ± ± 420420
HD 36112HD 36112 7900, 4.07900, 4.0 5.365.36 8000, 5.08000, 5.0 8100, 5.08100, 5.0 7750 7750 ± ± 358358
HD 53367HD 53367 31200, 31200, 4.54.5
3.613.61 29200, 4.029200, 4.0 31400, 31400, 4.04.0
31600 31600 ± ± 36503650
HD 17081HD 17081
• B7IV Classification
•Best Fit
• 13700 K
• Log(g)=4.0
• vsini=20 km/s
• Literature Results
• ~12300 K
HD 17081HD 17081
HD 17081HD 17081
HD 17081 Balmer FitsHD 17081 Balmer Fits
Best Fit: 11800 K, Log(g)=3.5
Best Fit: 12000 K, Log(g)=4.0
HD 34282HD 34282
• A0e+sh Classification
• Best Fit
• 10200 K
• Log(g)=4.5
• vsini=108 km/s
•Literature Results
• ~8700 (+410,-198) K
HD 34282HD 34282
HD 34282 Balmer FitsHD 34282 Balmer Fits
Best Fit: 9800 K, Log(g)=4.5
Best Fit: 10100 K, Log(g)=4.5
HD 36112HD 36112
• A8e Classification
• Best Fit
• 7900 K
• Log(g)=4.0
• vsini=52 km/s
• Literature Results
• ~7700 K
HD 36112HD 36112
HD 36112 Balmer FitsHD 36112 Balmer Fits
Best Fit: 8000 K, Log(g)=5.0
Best Fit: 8100 K, Log(g)=5.0
HD 31648HD 31648
• A3pshe+ Classification
• Best Fit
• 8200 K
• Log(g)=3.5
• vsini=95 km/s
• Literature Results
• 8700 K
• 9250 K, Log(g)=3.5
HD 31648HD 31648
Difficult Stars:Difficult Stars:BF OriBF Ori
• A5II-IIIe var
• Best Fit
• ~7500
• Log(g)~4.0
• vsini~53 km/s
• Literature Results
• 6750
BF OriBF Ori
HR DIAGRAM:HR DIAGRAM:New TemperaturesNew Temperatures
HR Diagram:HR Diagram:New Temperatures and New Temperatures and
DistancesDistances
HR Diagram:HR Diagram:New Temperatures and New Temperatures and Computed PhotometryComputed Photometry
FUTURE WORKFUTURE WORK Automated fitting for all field HAeBe stars Automated fitting for all field HAeBe stars
with ESPaDOnS observations.with ESPaDOnS observations. Use improved temperatures to improve Use improved temperatures to improve
mass and age estimates.mass and age estimates. Use Bayesian statistical approach to Use Bayesian statistical approach to
improving luminosities.improving luminosities.Major IssuesMajor Issues
Abundances for chemically peculiar stars.Abundances for chemically peculiar stars. Micro/macro turbulence.Micro/macro turbulence. Systematic normalization issues.Systematic normalization issues.
THE ENDTHE END
Balmer Line Normalization: Balmer Line Normalization: HD36112HD36112
Balmer Line Normalization: Balmer Line Normalization: HD139614HD139614
Balmer Line Normalization:Balmer Line Normalization:Comparison between ESPaDOnS Comparison between ESPaDOnS
and FORS1and FORS1HD 36112
Uncertainty vs SNRUncertainty vs SNRFor 15000 K synthetic model with 40 For 15000 K synthetic model with 40
km/s vsini.km/s vsini.
15000 K synthetic model 15000 K synthetic model with with
40 km/s vsini40 km/s vsini
Difficult stars:Difficult stars:HD 31293HD 31293
HD 31293HD 31293