most st meeting, halifax, may 31 - june 1, 2010 pulsation and granulation in the two pms stars v 588...
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MOST ST Meeting, Halifax, May 31 - June 1, 2010
Pulsation and Granulation in the two PMS stars
V 588 Mon and V 589 Monusing CoRoT data...
K. Zwintz, T. Kallinger, D. Guenther
MOST ST Meeting, Halifax, May 31 - June 1, 2010
V 588 Mon & V 589 Mon
• PMS members of NGC 2264
• Discovery of δ Scuti pulsation: Breger (1972)
• Recent Observations:
- multi-site campaign 2002
- MOST 2004: 48 days
- MOST 2006: 23 days
• First asteroseismic analysis:Guenther et al. (2009)
MOST ST Meeting, Halifax, May 31 - June 1, 2010
CoRoT & NGC 2264
• Dedicated short run (SRa01): March 2008 for ~23.4 days
• Exo field CCD
• 130 candidate targets for asteroseismology
• Additional: 14 „Imagettes“
- partially saturated images
- V 588 Mon & V 589 Mon
MOST ST Meeting, Halifax, May 31 - June 1, 2010
V 588 Mon seen with CoRoT
MOST ST Meeting, Halifax, May 31 - June 1, 2010
V 588 Mon seen with CoRoT
8 publishedpulsation frequencies(Guenther et al. 2009)
But there is more...
MOST ST Meeting, Halifax, May 31 - June 1, 2010
V 588 Mon: Comparison to MOST
close to orbit sidelobe
ok in MOST;not in gb data
MOST ST Meeting, Halifax, May 31 - June 1, 2010
V 589 Mon seen with CoRoT
MOST ST Meeting, Halifax, May 31 - June 1, 2010
V 589 Mon seen with CoRoT
published12 pulsation frequencies(Guenther et al. 2009)
And again: there is more...
MOST ST Meeting, Halifax, May 31 - June 1, 2010
Many additional frequencies...
V 588 Mon:106 „significant“
frequencies8 known frequencies
&98 „new“ frequencies
down to S/N=4
V 589 Mon:197 „significant“
frequencies
12 known frequencies&
185 „new“ frequenciesdown to S/N=4?
MOST ST Meeting, Halifax, May 31 - June 1, 2010
Granulation in A type stars
• Kallinger & Matthews (2010): 2 CoRoT targets
- power spectra: white noise + sum of power laws + Gaussian
> 1000 frequencie
spublished
420 frequenciespublished
55 frequencies
after granulation modelling
105 frequencies
after granulation modelling
MOST ST Meeting, Halifax, May 31 - June 1, 2010
Granulation in V588 Mon & V 589 Mon
• Prewhitening of the 10 / 15 largest amplitude frequencies
- Assumption: residual power excess is Gaussian-like
• Gaps in the data are filled by linear interpolation
- standard method for solar-type pulsators
• Global model fit to residual power spectrum
- power law components to correct the frequency-dependent background noise
- Signal-to-background-noise ratio (SNbR) to identify additional pulsation frequencies
MOST ST Meeting, Halifax, May 31 - June 1, 2010
Granulation Model for V 588 Mongap-filled residuals after prewhitening the 10 largest amplitude frequencies
solid line: global model fit
dotted line: 2 power laws and white noise
dashed lines: power lawsPeaks with SNbR > 9: significant additional pulsation frequencies
4 frequencies with SNbR > 9
MOST ST Meeting, Halifax, May 31 - June 1, 2010
Granulation Model for V 589 Mon
gap-filled residuals after prewhitening the 15 largest amplitude frequencies
22 frequencies with SNbR>9
MOST ST Meeting, Halifax, May 31 - June 1, 2010
• V 588 Mon
- 106 significant frequencies ⇒ 10 + 4 after granulation modelling
- one published frequency has SNbR < 9; but has to be included
- all 8 published frequencies are confirmed
Revised pulsation frequencies
• V 589 Mon
- 197 significant frequencies ⇒ 15 + 22 after granulation modelling
- all 12 published frequencies are confirmed
➡ Revised input for asteroseismic modelling
MOST ST Meeting, Halifax, May 31 - June 1, 2010
MOST & PMS stars:
Past and Future
MOST & PMS stars:
Past and Future
MOST ST Meeting, Halifax, May 31 - June 1, 2010
MOST & PMS stars in the past
• 5 Herbig Ae stars:HD 142666, UX Ori, HR 5999, V 1247 Ori, HD 34282
- the shortest period δ Scuti pulsator: HD 34282 (in prep.)
- the longest period δ Scuti pulsator: HR 5999(recent re-observations! to be published)
- no pulsational variability: UX Ori (in prep.)
- complex (pulsational) variabilities: HD 142666 (published)
- circumstellar matter ...
• NGC 2264 stars: no irregular variations
MOST ST Meeting, Halifax, May 31 - June 1, 2010
PMS stars - another view
A7e A7e
A7e
A5e
A3e
A3e
HR 5999 (2010)
MOST ST Meeting, Halifax, May 31 - June 1, 2010
Circumstellar matter in the 5 stars
• emission lines
• infrared excess
• circumstellar matter
- HD 142666 and UX Ori: “edge-on” & studied in detail
- HR 5999, V 1247 Ori and HD 34282: presence reported
MOST ST Meeting, Halifax, May 31 - June 1, 2010
The case of UX Ori
MOST ST Meeting, Halifax, May 31 - June 1, 2010
Spectral energy distributions
UX Ori
Work in progress...
MOST ST Meeting, Halifax, May 31 - June 1, 2010
PMS Target Proposal
• HD 35929
- RA = 05:27:42.8DE = -08:19:38.4
- V = 8.13 mag
- A5e
- single known period: 4.7 h
- switch target
- fundamental parameters available
GSC 05332-01468V = 9.7, sp = F2
GSC 05332-01325V = 10.2
Marconi et al. 2000
15‘
MOST ST Meeting, Halifax, May 31 - June 1, 2010
Why HD 35929?
• Herbig Ae star with similar spectral type to V 1247 Ori
- investigating the influence of the circumstellar matter with MOST
- check for additional pulsation frequencies at lower amplitudes
- similar to HR 5999 concerning length of pulsation period
‣ i.e. one of the longest period PMS pulsators
- fundamental parameters known (including parallax!)
- possibility for ground-based observations...
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