Accessing RAVE hardware for PLATO PIC Ulisse Munari Tomaz Zwitter.

accessing accessing RAVE RAVE hardwarehardwarefor for PLATOPLATO PICPIC

Ulisse MunariUlisse MunariTomaz ZwitterTomaz Zwitter

RAVE RAVE spectroscopyspectroscopy

8400-8800 8400-8800 ÅÅ range range 7500 resolving power7500 resolving power

Ulisse Munari & Tomaz Zwitter PLATO PIC Padova Jan 27, 2011



from repeated and standard star observations:

RV = 1.5 RV = 1.5 km/skm/s

Teff = 125 K Teff = 125 K

log g = 0.2 dexlog g = 0.2 dex

[[M/H] = 0.1 dexM/H] = 0.1 dex


<d>=30

0 pc

<d>=2 kpc






Geneva-Copenhagen

2011-01-01464,342464,342 spectra

of385,252385,252 stars

100,000dwarfs cooler

than F5

≈ ≈ 9000 dwarfs (of any metallicities, 9000 dwarfs (of any metallicities, chromospheric activity, binarity, etc.) over the chromospheric activity, binarity, etc.) over the

2000 deg2000 deg2 2 of the PLATO primary field of viewof the PLATO primary field of view


RAVE RAVE @ UKSchmidt @ UKSchmidt



150 fiber bundles150 fiber bundles

3 plates: one exposes on the 3 plates: one exposes on the sky, while another is confi-sky, while another is confi-gured for next exposuregured for next exposure

tipically 5 fields per nighttipically 5 fields per nightequiv. to 500/600 starsequiv. to 500/600 stars


n° of spectra collected per lunationn° of spectra collected per lunation

limitations: weather + n° of available fibers per plates

some periods of low statistics due to long calibrationruns with few stars exposed per plate or

very long integration on star clusters

long term average: 61,000 spectra per year


n° of spectra collected per lunationn° of spectra collected per lunation

limitations: weather + n° of available fibers per plates

some periods of low statistics due to long calibrationruns with few stars exposed per plate or

very long integration on star clusters

Dec 2010: new fiber bundle for plate #2, back to 140 fibers

April 2011: new fiber bundle for plate #1, back to 140 fibers ?

Fall 2011: new fiber bundle for plate #3 ?


n° of spectra obtained on each field. black = 2154n° of spectra obtained on each field. black = 2154

2011-01-01: 464,342464,342 spectra of 385,252385,252 stars


n° of visits to a given field


re-observatios of randomly selected RAVE targets coupled with re-observatios of randomly selected RAVE targets coupled with high RV accuracy (high RV accuracy (±±1.5 km/s1.5 km/s) has allowed the discovery of many ) has allowed the discovery of many new SB1 binariesnew SB1 binaries


many already known SB1 stars have been by chance surveyed by many already known SB1 stars have been by chance surveyed by RAVE, and their measured RVs well match published orbitsRAVE, and their measured RVs well match published orbits


accessing RAVEaccessing RAVE

• at present at present RAVE is fully funded to June 2012, probable to RAVE is fully funded to June 2012, probable to Dec 2012. After that the situation is unclear at the moment,Dec 2012. After that the situation is unclear at the moment, including possible interest for the hardware by other partiesincluding possible interest for the hardware by other parties (like a revamped interest by the 6dF galaxies survey)(like a revamped interest by the 6dF galaxies survey)

• RAVE can suspend operation for 6 months (or 3 + 3 months) RAVE can suspend operation for 6 months (or 3 + 3 months) to allow PLATO to access the hardware before 2013, to allow PLATO to access the hardware before 2013, if necessaryif necessary

• with RAVE-funded (2011) replacement of old and damaged fiber with RAVE-funded (2011) replacement of old and damaged fiber bundles (as left over by the 6dF red-shift galaxy survey) andbundles (as left over by the 6dF red-shift galaxy survey) and provision of a brand new fiber plate, provision of a brand new fiber plate, the number of availablethe number of available fibers will fibers will ~double compared to last four years~double compared to last four years



• PLATO PIC has to provide the list of 50,000 stars to be PLATO PIC has to provide the list of 50,000 stars to be observed, selected on appropriate criteria, and matching the observed, selected on appropriate criteria, and matching the multiplex capability of the instrument multiplex capability of the instrument

• The UK Schmidt staff carries out the observations and deliverThe UK Schmidt staff carries out the observations and deliver the 2D frames to PLATO PIC (science, flat, dark, calib, etc.)the 2D frames to PLATO PIC (science, flat, dark, calib, etc.)

• the cost for 6 months of exclusive use of the telescope isthe cost for 6 months of exclusive use of the telescope is 300,000 Aus$ ≈ 220,000 Euro (3 dark weeks per lunation300,000 Aus$ ≈ 220,000 Euro (3 dark weeks per lunation))

• this means that under mean local weather statistics 50,000 this means that under mean local weather statistics 50,000 suitable spectra can be collected in 6 months of operationsuitable spectra can be collected in 6 months of operation on stars of V≈ 11.5on stars of V≈ 11.5


accessing RAVEaccessing RAVE• extracting/calibrating/analysing the 2D data and gettingextracting/calibrating/analysing the 2D data and getting out of them good VRad, Teff, log g and [M/H] is an expert out of them good VRad, Teff, log g and [M/H] is an expert process, that would take long time to work out from scratchprocess, that would take long time to work out from scratch

• the RAVE Consortium will be willing to carry out these tasksthe RAVE Consortium will be willing to carry out these tasks for free with its proprietary pipelines and paid man-power, iffor free with its proprietary pipelines and paid man-power, if in return the RAVE Consortium will be allowed to use the in return the RAVE Consortium will be allowed to use the products (VRad, Teff, log g, [M/H],…) for its own studies of products (VRad, Teff, log g, [M/H],…) for its own studies of the Milky Way structure and evolution, once they have served the Milky Way structure and evolution, once they have served the PLATO PIC goals of selecting and characterizing the missionthe PLATO PIC goals of selecting and characterizing the mission targets targets

• some 30,000 Euro could be saved if a PLATO student would besome 30,000 Euro could be saved if a PLATO student would be employed in the observations. Because the UK Schmidt + 6dF employed in the observations. Because the UK Schmidt + 6dF is an expert instrument, this student needs extensive training.is an expert instrument, this student needs extensive training. RAVE could offer this training during its observing runs in the RAVE could offer this training during its observing runs in the months preceeding the start of PLATO operations.months preceeding the start of PLATO operations.



• maintaining the current RAVE wavelength range (8400-8800,maintaining the current RAVE wavelength range (8400-8800, well suited for solar-type dwarfs) would build on already securedwell suited for solar-type dwarfs) would build on already secured extensive calibration observations, saving precious observing timeextensive calibration observations, saving precious observing time

• the cost of 220,000 Euro appears well within grasp of funding the cost of 220,000 Euro appears well within grasp of funding requests to national agencies willing to support PLATOrequests to national agencies willing to support PLATO

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Accessing RAVE hardware for PLATO PIC Ulisse Munari Tomaz Zwitter.

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