Investigation of rotation: one of the main goalRotation of the Sun: clearly visible by sunspots
Joergen Christensen-Dalsgaard
Hungarian Asteroseismology GroupEstablished: 2005 -
Participants: Margit Paparó D.Sc. – project scientist
Zoltán Kolláth D.Sc. – guest investigator of CoRoT
Zoltán Csubry PhD student
József Benkő PhD
Sódorné Bognár Zsófia PhD student – employee by HAG
László Szabados D.Sc.
Róbert Szabó PhD
László Molnár student – employee by HAG
Krisztián Sárneczky – PhD student – employed for 5 month
Honorary members of HAGPISTA – Piszkéstető Student’s Astronomy ELTE University
• Eszter Bokor• Gyöngyi Kerekes• András Már• László Molnár• Emese Plachy• Péter Pápics • Nándor Sztankó
Fields of activitiesFields of activities
• Photometric characterization of seismo Photometric characterization of seismo targetstargets
• Time series photometry of exofieldsTime series photometry of exofields
• Guide for subfield selection: ROTSE-IGuide for subfield selection: ROTSE-I
• Successful applications:Successful applications:
- Low amplitude variation of classical - Low amplitude variation of classical
pulsating stars (GI Zoltán Kolláth)pulsating stars (GI Zoltán Kolláth)
- Blazhko and double mode RR Lyrae - Blazhko and double mode RR Lyrae starsstars
(headed by Merieme Chadid, France)(headed by Merieme Chadid, France)
Pulsating stars studied by Pulsating stars studied by COROTCOROT
• Radial region: Radial region: long periods – long periods – exofieldsexofields
• Non-radial region: Non-radial region: main sequence – main sequence – shorter periodsshorter periods
Joergen Christensen Dalsgaard
Targets of asteroseismology: existing Targets of asteroseismology: existing oscillationsoscillationsamplified by 100000 (David B. Guenther)amplified by 100000 (David B. Guenther)
Propogation of wavesPropogation of waves with different parameterswith different parameters
• White White – – ll = = 00
• BlueBlue – – ll = = 22
• GreenGreen – – ll = = 2020
• YellowYellow – – ll = = 2525
• RedRed – – ll = = 7575
Joergen Christensen-Dalsgaard
Method of inversion – Method of inversion – asteroseismologyasteroseismology
Differential layer between Differential layer between GreenGreen and and YellowYellow waves is waves is investigatedinvestigated
Many waves – many layers are studied
Joergen Christensen-Dalsgaard
Data obtained for Theta Data obtained for Theta TucanaeTucanae6 weeks, three sites – single site 20 years 6 weeks, three sites – single site 20 years earlierearlier
First step of inversionFirst step of inversionfinding the frequencies of wavesfinding the frequencies of waves
• 10 waves were 10 waves were identifiedidentified
• Binary nature Binary nature was discoveredwas discovered
• SpectroscopicallSpectroscopically confirmed y confirmed laterlater
Photometry of seismo Photometry of seismo targets Itargets I
•Summer targetsSummer targets: :
2005 20062005 2006
HD 181555 3 8 HD 181555 3 8 nightsnights
HD 180642 2 5HD 180642 2 5
HD 170782 - 3HD 170782 - 3
Photometry of seismo targets IIPhotometry of seismo targets II
•Summer Summer targets:targets:
2005 20062005 2006 HD 172189 2 - HD 172189 2 -
nightsnights
•Winter targets:Winter targets:
HD 44195 8 3HD 44195 8 3
HD 44283 4 3HD 44283 4 3
Photometry of seismo targets Photometry of seismo targets IIIIII
•Winter targets:Winter targets: 20062006• HD 50844 7 nightsHD 50844 7 nights
•Other objectsOther objects HD 48434 – Gamma HD 48434 – Gamma
DorDor starstar• V920 Aql – RR Lyrae V920 Aql – RR Lyrae
starstar on the exofieldon the exofield
Time series on exofield of Time series on exofield of HD 49933+ HD 49434HD 49933+ HD 49434
selection on star density or well-known star in the selection on star density or well-known star in the fieldfield
More effective selection of More effective selection of subfields:subfields:ROTSE - IROTSE - I
Posters on 8. CoRoT week:Posters on 8. CoRoT week:
József M. Benkő and Zoltán CsubryJózsef M. Benkő and Zoltán Csubry ROTSE-I All Sky Survey as a Tool of ROTSE-I All Sky Survey as a Tool of
Target Selection in the COROT Target Selection in the COROT FieldsFields
Zoltán Csubry, Zoltán KolláthZoltán Csubry, Zoltán Kolláth
MUFRAN – A scriptale data MUFRAN – A scriptale data
processing tool for variable starsprocessing tool for variable stars
Made by Zoltán Kolláth
Strange modes in stars
COROT data will be analized here
Cepheid horn: oscillations are the same as in the star