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G-K Giants Meeting 22 Feb 2005 ESO Garching Johny Setiawan Max-Planck-Institut für Astronomie. The K giant‘s friends/fans (as I know). other collaborations. TLS-Tautenburg Artie Hatzes. ESO Garching Luca Pasquini Michaela Döllinger. Obs. Nacional + Univ. Rio Licio da Silva - PowerPoint PPT Presentation
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G-K Giants Meeting22 Feb 2005
ESO Garching
Johny Setiawan
Max-Planck-Institut für Astronomie
The K giant‘s friends/fans (as I know)
Obs. Nacional + Univ. RioLicio da SilvaJ. Renan de Medeiros
ESO GarchingLuca PasquiniMichaela Döllinger
KIS-FreiburgOskar von der Lühe
MPIA-HeidelbergJohny SetiawanPatrick Weise, Florian Klotz
TLS-TautenburgArtie Hatzes
PadovaLeo Girardi
other collaborations
FEROS at 1.52m ESO Oct 1999 – Feb 2002
FEROS at 2.2m MPG/ESO Dec 2003 – Jun 2007? (run as secondary program in MPG GT)
Data acquisition (as I know)
observation gap Feb 2002 – Dec 2003 (few CORALIE measurements)
HERCULES at 1.0m MJO/NZ Dec 2004 – Jun 2007? (run as secondary program in complementary to PRIMA)
TLS spectrograph at 2m Tautenburg from ? – now ?
others (run in brazilian time ? other TLS time ?)
Method Messenger 102, 13
Substellar candidate HD 47536 b A&A 2003 398, L19
Multiple systems A&A 2004 421, 241
ASP 318, 2004, 283
First results A&A 2003 397, 1151
Extrasolar planets of K giants ESA SP-538 2004, 87
ESA SP-529 2004, 595
Chromospheric activity Cool Star Meeting 13
Substellar candidate HD 11977 b A&A 2005 submitted
Published results (2000 - now)
Some new results
Not yet published as binary
Reveals offset FEROS-CORALIE ~35 m/s
Some new results
Starspots model
Launhardt & Setiawan 2005(in preparation)
Some new results
HD 81797 (alpha Hya)
P (MJO) ~ 400 dP (La Silla) ~ 450 d
Some new results
HD 81797 (alpha Hya)
Some new results
Weise & Setiawan 2005(in preparation)
BISECTOR variation Lithium variation
Some new results
Short period oscillationP= 2.9 day
Setiawan, Roth, Weise & Döllinger 2005(in preparation)
2.2m MPG GT(Nov 2004)
Some new results
hours oscillation ?
to be confirmed with HARPS !
minutes oscillation ?
Some new results
Setiawan et al. 2005(submited)
Some new results
secondary orbit ?follow up observationneeded
Some new results
need updated orbital solution
(My) conclusion
G and K giants can show short-term or/and long-term radial velocity variation (in agreement with previous results).
Short-period oscillation : stellar pulsation
Long-period oscillation : rotational modulation or companion
We found various evidences for
• pulsation (at least 2),
• rotational modulation (at least 8)
• as well as substellar companions (at least 3)
in our target sample (~100 stars). However, we need more data to confirm each of these evidences (need successful proposals for ESO time).
Proposed study
• Trend of radial-velocity variability (sigma RV) across the RGB.
• Check chromospheric activity indicator Ca II K (as done for HD 78647).
• Check for special abundance variation (as done for HD 81797).
• Check for bisector variation of special orders (instead of all orders), looking for periodicity solar-like oscillations.
• Search for extra-solar planets around intermediate-mass giants.
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