TDA discussion. Sergio Campana Osservatorio astronomico di Brera

Transcription

1 TDA discussion Sergio Campana Osservatorio astronomico di Brera

2 Discoveries 17 s s s s - Hydrogen poor superluminous SNe SN 2011fe (Type Ia CO-WD) R PTF [mag] L Edd for 50M star 0.1M Ni 56 +Co Abs. R [mag] - SNIIn 40d before explosion (PTF 10tel) Tidal disruption an He star JD [day] 12 Absolute u band AB magnitude S SS SCP 06F6 SN 2005ap PTF09cnd PTF09cwl PTF09atu PTF10cwr Rest frame phase (days)

3 What is left? Discovery space (left): - sourn hemisphere (but DES 4m deg 2 ) - high-cadence survey - IR (& UV) coverage - multi-band surveys - follow-up machines - GW & neutrino triggers at Europe longitudes and/or sourn sky

4 Possibilities do nothing (train already left...) do something (money...) - build a new survey machine - build a spectroscopic follow-up machine - (re)use an existing facility - enter in new (or on-going) surveys (LSST)

5 Given CCD plate scale 0.9 arcsec/pixel re is ample margin for mirror optical quality. For S.can Campana feed two main instruments: multi-bandpart imaging B2 camera and low-resolution spectrograph. focal plane SMT proposed configuration foresee a 3 mirror (M3) mounted on a rotating device than rd focal plane telescope will be collimated and a 90 pick f mirror (M3) will bend light into a plane can feed two main instruments: multi-band imaging camera and low-resolution spectrograph. competitive with existing surveys (but with multi-band consist capabilities), leaving configuration or observing normal telescope axis. bemulti-band photometer in awill dichroic tree-like that time for focal to plane telescope will collimated and a 90 pickwill f mirror (M3) bend light into a plane external triggers, follow up discovered transients orconsist monitoring interesting sources. willnormal split light in axis. wavelength domain towards will dedicated (based configuration on experience to telescope multi-band photometer in a cameras dichroic tree-like that will splitinstrument light in at wavelength domain towards using dedicated cameras on experience It has become customary toeso/mpi compare so-called etendue, a product a telescope GROND 2.2surveys m in La Silla). same(based collimated beam will also feed GROND instrument instrument ESO/MPI 2.2field m in La Silla). as same collimated will also feed a dispersing system thatat projects spectra into dedicated collimated beam allows collecting area, A, and view,!, acamera. figure beam merit (FoM). However, etendue dispersing system that projects spectra into dedicated camera. collimated beam allows adoption identical focalinstrument reducers forand eachsays channel (photometric and spectrograph) with evidentout, reduction simply characterises nothing about how survey is carried e.g., depth, adoption identical focal reducers for each channel (photometric and spectrograph) with evident reduction optical manufacturing costs. In Figure 2 a sketchasanone telescope isa survey s shown anddiscovery in Table 3potential, its main a product coverage rate, cadence, etc. Djorgovski indicator optical manufacturing costs. In Figure 2proposed a sketch one telescope is shown and in Table 3 its main characteristics are reported. are reported. its characteristics spatio-temporal coverage rate, C, and estimate depth, D, which may be reasonably expressed as proportional to S/N ratio individual exposures. coverage rate C can be expressed as Table 3: Telescope characteristics. Table 3: Telescope characteristics. C=R"Np"feff where R is area coverage in deg2/night (not counting repeated exposures), Np is number ValuesValues passes per field in a given night, feff is fractiontelescope Telescope effective observing time averaged over year characteristics characteristics (including wear losses, engineering time). depth D can be expressed as D=[A"texp"!]1/2/FWHM diameter 1000 mm M1 diameter 1000 mm (!S/N), where A is effective collecting area M1 telescope, t exp is average exposure time,! is M2 M2 diameter 200 mm diameter 200 mm resolution. product overall efficiency (throughput) instrument, and FWHM Field view is typical 1 deg2 image Field view 1 deg2 Pixel scale C"D=DRE represents a Figure Merit (FoM) for a Discovery Rate100 arcsec/mm Events (DRE), and net discovery Pixel scale 100 arcsec/mm Focal ratio 1.8 (than etendue) to characterise potential a given survey. refore, DRE is a more relevant measure Focalspeed ratio Pointing 2 deg/s1.8 planned and future surveys. Pointing speed 3 arcsec2 rms deg/s Pointing accuracy Build a (small) new facility GROND-like including H&J S. Campa competitive with external triggers, Pointing accuracy 3 arcsec rms Tracking error S. Campan 0.2 arcsec/10min Table 1: ongoing and planned surveys Figure Merit parameters (from Djorgovski et al. 2012). two lines for It has become c Tracking error 0.2 arcsec/10min Figure 2: Telescopes assembly. S. Campana Part B2 EVENT (3 telescopes) refer for half or full use three telescopes in survey mode. LSST is still to be built (foreseen competitive with A collecting area, Figure 2: Telescopes assembly. for 2020). Gruppo di Ottiche e LEnti a with Merate existing (GOLEM) group at (but Osservatorio Brera (OAB) worked out competitive surveys with dimulti-band capabilities), leaving or observing time for f external triggers, simply character telescope optical design. mechanical structure designs will be finalized after approval within 3 months. Survey Npfollow feff up Area Re LEnti FWHM C D!transients exp Osservatorio Gruppo di Ottiche a Merate (GOLEM) att di or Brera (OAB) worked out DRE external triggers, group discovered monitoring interesting sources. It has become cu telescope is already provided with fast moving capabilities and it is fully planned for a robotic control. 2 2 (deg /n)mechanical ) compare (arcsec) (s) besurveys rate, ca telescope optical design. structure(m designs will finalized after approval within 3 months. Cover Depth Disc.Ratea product coverage has become customary using so-called telescope mechanicalitlayout will be an alt-az, guarantyingtoa cost minimization considering its scalability with etendue, collecting area, A, respect telescope is already provided fasttelescope movingtechnology capabilities and it fast is fully planned for a robotic control. solutions. State with guarantee characteristics both0.9 CRST to existing art field 0.7 pointing its spatio-temp collecting area, A, and instrument view,!, as a figure merit (FoM). However, etendue in mechanical layoutstiffness will bethanks an alt-az, cost considering scalability with terms structural to guarantying increasing ause minimization new materials (Carbon Fiber its Reinforced simply characteris PTF survey simply characterises instrument and saysquotations nothing about how is carried out, depth, respect to existing solutions. State (direct art telescope technology guarantee fast pointing characteristics both 4800 Plastic), and rapid and precise motions drive motors). Telescope are reported below ase.g., proportional coverage rate, cad (Section5).structural As acoverage general rule800 wethanks obtained quotation for all use prices we included in proposal. 2 toa proposed in Skymapper1 terms stiffness increasing new materials (Carbon Fiber rate, cadence, etc. Djorgovski as an indicator Reinforced a3.1survey s discovery potential, a product C=R"N "f p eff whe Plastic), and rapid andspatio-temporal precise (direct motors). Telescope quotations are reported below PanSTARR motions drive and its spatio-tempo its coverage rate, C, estimate depth, D, which may be reasonably expressed 3 (Section 5). As material a general(all rule we obtained a quotation instrumental for1 all prices we includedetc.) in proposal Supporting quotations, endorsements, characteristics, is not insert-. bepasses perasfiel EVENT 800 atto rate C canas as but proportional S/N 2.38 ratio 60 individual exposures. coverage expressed proportional to ed in proposal is available site (including w C=R"Np"f in deg /night counting exposures),c=r"n Np is p"f number EVENT R is 0.7 area 2.381coverage (not repeated 5800! eff where eff wher Supporting material (all quotations, endorsements, instrumental characteristics, etc.) is not insert but passes per field in 0.75 a given night, feff 7500 effective over where year A is 0.8 fraction observing edlsst in proposal is available at site time averaged (!S/N), passes 1/2 per field (including wear losses, engineering time). depth D can be expressed as D=[A"texp"!] /FWHM! overall efficiency (including (!S/N), where Afor is on-going effective collecting area texp is average exposure time,! is wea 8 planned In Table 1 we report parameters and surveys; twotelescope, rows for EVENT correspond (!S/N), where A C"D=DRE repre to lower and upperoverall bound efficiency (50% or 100%) totalobserving time dedicated to survey. se numbers (throughput) instrument, and FWHM is typical image resolution. product overall efficiency allow us to put into a wider context capabilities Merit our survey. respectively we see C"D=DRE represents a Figure (FoM)Based for aondiscovery Rate DRE, Events (DRE), and net discovery potential a giv M Progetto Premiale/Bandiera that May EVENT is highly competitive current large area surveys, Skymapper1 and(than PTF. etendue) Friday, 10, 2013 survey potential a given survey.with refore, DRE is a morelike relevant measure to characterise C"D=DRE repres

6 Build a survey facility Same as above but at a European level Larger telescopes (2m) IR only (H, J & K), or GROND-like? Include existing telescopes (Liverpool, NOT,?) Funds at European level: OPTICON, FP7, ERC-Synergy

7 Build/adopt a follow-up machine Needs PESSTO 3-4 m spectroscopic telescope 90n/yr Agreements with existing survey(s) Not able to cover GW & neutrino triggers Funds at European level: OPTICON, FP7, ERC-Synergy

8 Use an existing facility Not many Schmidt telescope at ESO used by US collaboration (LaSillaQuest)... VST

9 VLT Survey Telescope VST at Cerro Paranal 2.65 m primary (active optics) 32 2kx4k CCDs (OmegaCAM) 1deg x 1deg FOV 0.22 arcsec/pixel u, g, r, i, z filters (Halpha) VIDEO VIKING Ultra-VISTA VHS VVV VMC VIDEO VIDEO VIKING VIDEO

10 Exposures 30 s 1 min u Additional times g r CCD read out 40 s Filter change 35 s Move tel. 1 deg 30 s i z (slew 1 deg/s)

11 Options Option I: large program at ESO-VST (when fered to public?) Option II: hands-on VST to carry out a very large synopthic survey and implement an RRM (Progetto Premiale?)

12 Enter in LSST INAF (vague) interest Identify technology and science interests Far far away No GW & neutrino follow-up

13 Future NTT (in parallelo con il Pasquini/Marconi - Vettolani - INAF) MdV (Pasquini)/FM (Marconi). Covino. VLT (Large project). Futuro. DES. VST & VISTA new survey (next year explorative survey su tempo bright/grey per farsi le ossa ) EC VST & VISTA GW search (dal up to 40 n). MB per call GW experiments.