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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
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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 J. Renan de Medeiros Padova Leo Girardi KIS-Freiburg Oskar von der Lühe MPIA-Heidelberg Johny Setiawan Patrick Weise, Florian Klotz
Data acquisition (as I know) FEROS at 1.52m ESO Oct 1999 – Feb 2002 observation gap Feb 2002 – Dec 2003 (few CORALIE measurements) TLS spectrograph at 2m Tautenburg from ? – now ? others (run in brazilian time ? other TLS time ?) FEROS at 2.2m MPG/ESO Dec 2003 – Jun 2007? (run as secondary program in MPG GT) HERCULES at 1.0m MJO/NZ Dec 2004 – Jun 2007? (run as secondary program in complementary to PRIMA)
Published results (2000 - now) Method Messenger 102, 13 First results A&A 2003 397, 1151 Substellar candidate HD 47536 b A&A 2003 398, L19 Extrasolar planets of K giants ESA SP-538 2004, 87 ESA SP-529 2004, 595 Multiple systems A&A 2004 421, 241 ASP 318, 2004, 283 Chromospheric activity Cool Star Meeting 13 Substellar candidate HD 11977 b A&A 2005 submitted
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 d P (La Silla) ~ 450 d
Some new results HD 81797 (alpha Hya)
Some new results Lithium variation BISECTOR variation Weise & Setiawan 2005 (in preparation)
Some new results 2.2m MPG GT (Nov 2004) Short period oscillation P= 2.9 day Setiawan, Roth, Weise & Döllinger 2005 (in preparation)
Some new results hours oscillation ? minutes oscillation ? to be confirmed with HARPS !
Some new results Setiawan et al. 2005 (submited)
Some new results secondary orbit ? follow up observation needed
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.