precision stellar physics from the ground andrzej pigulski university of wrocław, poland special...
TRANSCRIPT
![Page 1: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/1.jpg)
Precisionstellar physics
from the ground
Andrzej PigulskiUniversity of Wrocław, Poland
Special Session #13: High-precision tests of stellar physics from high-precision photometry
![Page 2: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/2.jpg)
Asteroseismology:satellite observatories
SatelliteWIRE
(tracker)MOST CoRoT Kepler
Launch 1999 2003 2006 2009
Tel. diam. [cm] 5.2 15 27 90/140
V range < 4 < 6 5.5 - 9 (sei.)11.5 - 16 (plan.) 9 - 16
Typical precision*(single meas.) [ppm] 200 70 150 200
Detectionthreshold [ppm]** 80 20 3 3
* bright star, ~1-min (stacked) integration, ** for one-month long observations
![Page 3: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/3.jpg)
Ground-based observing campaigns
DUTY CYCLE DETECTION THRESHOLD
< 60%, typically ~20% > 0.08 mmag, typically ~1 mmag
In comparison with satellite data: lower duty cycle, worse detection
threshold
![Page 4: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/4.jpg)
Ground-based observing campaigns
NGC 6910 campaign: single-site data, 81 observing nights
Aliasingproblem
![Page 5: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/5.jpg)
Observations:satellite vs. ground-based
SATELLITE DATA:•high duty cycle (up to ~100%),•outstanding precision,•low noise at low frequencies.
Do we still need ground-based photometry ?
LIGHTCURVE
FREQUENCYSPECTRUM
Pápics et al. (2012)
SPB star HD 43317, CoRoT
![Page 6: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/6.jpg)
Evolutionary & puls. models,theoretical frequencies
global parameters
Asteroseismology:how it works?
Photometricobservations provide:• frequencies,• amplitudes,• phases.
Mode identification:quantum numbers ℓ,m,n
RVsline profiles
Frequency matching
Constraints on internal rotation, overshooting, ...
Mode ID of the remaining modes
Stabilitycheck
ASTEROSEISMOLOGY
![Page 7: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/7.jpg)
Asteroseismology:how modes are identified?
How modes are identified?
1. asymptotic relations &rotational splitting
2. period ratios3. multicolour photometry
and/or spectroscopy(many mode ID methods)
![Page 8: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/8.jpg)
Mode ID:asymptotic relations
J.Christensen-Dalsgaard
driving mechanism:- self-excited pulsations,- stochastically excited pulsations (solar-like)
character:- p modes (acoustic)- g modes (gravity)
asymptotic relations(for a given ℓ):p modes: equidistant in frequency g modes: equidistant in period
solar-likeoscillations
![Page 9: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/9.jpg)
Mode ID:asymptotic relations
Bedding & Kjeldsen (2003)
The Sun
SOHO/VIRGO
![Page 10: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/10.jpg)
Mode ID:asymptotic relations
Chaplin et al. (2010)
Δν = large separation
δν02 = small separation
![Page 11: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/11.jpg)
Mode ID:asymptotic relations
White et al. (2011)
echelle diagram: frequency vs. frequency modulo large separation
Bedding et al. (2010)
ℓ= 2 0 1 2 0 3 1
![Page 12: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/12.jpg)
Mode ID:asymptotic relations
J.Christensen-Dalsgaard
asymptotic relations(for a given ℓ):p modes: equidistant in frequency g modes: equidistant in period
solar-likeoscillationspulsating
(pre)whitedwarfs
+hot
subdwarfs
rotational splitting:multiplets with (2ℓ+1) components
![Page 13: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/13.jpg)
Mode ID:asymptotic relations
PG 1159 starRXJ 2117+3412
Average period spacing = 21.618 s ℓ = 1 modes
Vauclair et al. (2002)
![Page 14: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/14.jpg)
Mode ID:asymptotic relations
Pulsating hot subdwarfKIC 5807616
Reed et al. (2011)
Average period spacing = 242.12 s ℓ = 1 modes
Average period spacing = 139.13 s ℓ = 2 modes
blue = observed
![Page 15: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/15.jpg)
Mode ID:rotational splitting
Pulsating hot subdwarfKIC 10139564
Baran et al. (2012)
ℓ = 2
ℓ = 1
![Page 16: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/16.jpg)
Asteroseismology:how modes are identified?
How modes are identified?
1. asymptotic relations & rotational splitting2. period ratios3. multicolour photometry
and/or spectroscopy(many mode ID methods)
![Page 17: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/17.jpg)
Mode ID:period ratios
J.Christensen-Dalsgaard
solar-likeoscillationspulsating
(pre)whitedwarfs
+hot
subdwarfs
period ratios: double/triple-mode pulsators, radial modes
classicalpulsators
![Page 18: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/18.jpg)
3O/1O
2O/1O
3O/2O
Mode ID:period ratios
Data: OGLE (LMC)Soszyński et al. (2008, 2010),Poleski et al. (2010)
HADS RRd
CEPHEIDS
1O/F
![Page 19: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/19.jpg)
Asteroseismology:how modes are identified?
How modes are identified?
1. asymptotic relations & rotational splitting2. period ratios3. multicolour photometry
and/or spectroscopy(many mode ID methods)
single-band (satellite)photometry is
sufficient for applying 1 and 2
![Page 20: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/20.jpg)
Mode ID:multicolour photometry & spectroscopy
J.Christensen-Dalsgaard
driving mechanism:- self-excited pulsations,- stochastically excited pulsations (solar-like)
character:- p modes (acoustic)- g modes (gravity)
solar-likeoscillationspulsating
(pre)whitedwarfs
+hot
subdwarfs
classicalpulsators
multicolour photometry& spectroscopy main-sequence pulsators + hot subdwarfs
main-sequencepulsators +
hot subdwarfs
![Page 21: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/21.jpg)
Mode ID:multicolour photometry & spectroscopy
Diagnostic diagrams:
Amplitude ratio vs. phase difference
Cugier et al. (1994)
![Page 22: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/22.jpg)
Mode ID:multicolour photometry & spectroscopy
Diagnostic diagrams:
Amplitude ratio (RV/phot.) vs. amplitude ratio (colour/band)
Cugier et al. (1994)
![Page 23: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/23.jpg)
Mode ID:multicolour photometry & spectroscopy
Diagnostic diagrams:β Cephei star ν Eridani:
goodness-of-fit parameter χ2 vs. ℓ
Daszyńska-Daszkiewicz & Walczak (2010)
0 1 1 1 1,2
1
0,1,3 1,2,3
2,5
![Page 24: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/24.jpg)
Mode ID:multicolour photometry & spectroscopy
Kepler β Cephei/SPB hybrids
Balona et al. (2011)
![Page 25: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/25.jpg)
Mode ID:multicolour photometry & spectroscopy
The methods using multicolour photometry and spectroscopy for mode ID require ground-based data.
A lot of interesting physics to study:
- internal (core) rotation,- amount of overshooting from the core,- diffusion,- testing stellar opacities.
![Page 26: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/26.jpg)
An example: Z-effect
Pamyatnykh 1999
Rudolph et al. 2006
![Page 27: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/27.jpg)
Physics to probe
Daszyńska-Daszkiewicz & Walczak (2010)
β Cephei star ν Eridani
![Page 28: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/28.jpg)
Evolutionary & puls. models,theoretical frequencies
global parameters
Asteroseismology:how it works?
Photometricobservations provide:• frequencies,• amplitudes,• phases.
Mode identification:quantum numbers
RVsline profiles
Frequency matching
Constraints on internal rotation, overshooting, ...
Mode ID of the remaining modes
Stabilitycheck
ASTEROSEISMOLOGY
![Page 29: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/29.jpg)
Ground-based vs. satellite
SATELLITE:•higher duty cycle (up to ~100%),•better precision,•low noise at low frequencies (?).
GROUND-BASED:•cheaper,•multicolour photometry (exc. BRITE, however),•spectroscopy,•all sky available.
Do we still need ground-based photometry ?
YES, WE DO...
![Page 30: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/30.jpg)
β Cephei stars: ASAS contribution
(Southern) ASAS sky: δ < +28°, ~300 new β Cephei stars Pigulski & Pojmański (2010)
CoRoT „eyes”
Kepler field
![Page 31: Precision stellar physics from the ground Andrzej Pigulski University of Wrocław, Poland Special Session #13: High-precision tests of stellar physics from](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bf741a28abf838c7fc49/html5/thumbnails/31.jpg)
Conclusions
1.Ground-based and satellite data are complementary.
• Ground-based data are crucial for characterization of all and asteroseismology of some stars.
2.There are good prospects for testing stellar physics and stellar interiors with ground-based data.