tmt on la palma or maunakea

Prepared by TMT DEOPS

1

TMT on La Palma or Maunakea. Construction status.

Assessment of alternate sites.

Prepared by TMT DEOPS Team For TMT ISDT members

Version date: May 26, 2017 TMT.OPS.PRE.17.009.REL01


2

!  ObservatoryConstruc0onPhaseUpdate!  Technicaldevelopment!  Theneedtoiden0fyasiteandbeginconstruc0on

!  AssessmentofAlternateSitesandtheDecisionProcess!  Solicita0onofproposals!  Abilityofpoten0alsitestosupportTMTscience

!  Sitecharacteris0csandsystemperformance!   ThemajoreffortofDEOPSgroupwithAOgroup

!  Keyresults!  Availableobservingmodesandabilitytosupportscience

!  ORMsupportsTMTscience,construc0onandopera0ons

Overview of Talk


3

Technical development Allcri0calsystemsinconstruc0onorfinaldesignphasesDevelopmentproceedinginallareas


4

The need to begin on-site construction

!  On-siteconstruc0onisdomina0ngthecri0calpathitemsintheprojectschedule

!   Projectfundingisdependentonfollowingacertainpacing

!  UncertaintyaboutpermiIng0mescalesandsiteaccessforMaunakea

!  Necessarytoevaluatealternateop0onsforasiteforTMT

!  ThesitemustsupportthesciencegoalsforTMT

!  Thesitemustsupport0melyconstruc0onandopera0ons


5

Assessment of Alternate Sites and the Decision Process

!   Solicita0onofproposals!   On-siteconstruc0onmustbeginbyApril2018

!  BoarddecisionplannedOctober2017!   Followingvaca0onofHawaiiCDUP(Dec.2015)acallforproposalstohostTMTwascirculated(Feb.2016)!  Proposalsincludedsitecharacteris0cs,logis0calandprogramma0cinforma0on

!  Poten0alsitesaYersolicita0onsreceived:!   India(Hanle)!   China(Ali)!  Mexico(SanPedroMar0r)!   CanaryIslands(ObservatoriodelRoquedelosMuchachos)!   Chile(MackennaandHonar)

!   Ini0alexamina0onandfirstdownselect!   DuetoremotenessbothHimalayansiteshadverysignificantlogis0calconcernsandwhilstgenerallyverygoodsites,theywerelessabletosupportthespecificTMTScienceCasesthantheothers


6


!   Furtherinves0ga0onsofsitecharacteris0cs!   LargeeffortbytheTMTDEOPSgrouptodevelopaconfidentunderstandingofthecharacteris@csofpoten@alsites

!  Maintaskswereinforma0ongatheringandanalysis!   Short0mescaledrivenbydeadlinefordecision(Oct.2016)!   No0meforaddi0onalsitetes0ng–Usepre-exis0ngsourcesofinforma0on

!   Crosschecksofallresultsfromindependentdatasets!   Inves0ga0ngconcernsanddevelopingdataproductstoallowperformancemodelingandscien0ficproduc0vitytobeevaluated

!   Alsosolicitedadetailedclimatechangestudy!   Parallelexamina0onofcost,schedule,technicaland

logis0calissuesbyprojectmanagement,projectteamsandsub-groupofTMTboard–Verysignificanteffort


7

Sources of Information Site Seeing/

turbulenceWind PWV Clear

frac@onNight@metemperature

Skybrightness Transparency Groundleveldust

Rela@vehumidity

Mirrordegrada@on

ORM RawdataIAC,ESO,NOAA,WHT/CANARY.InternalTMTanalysis

IAC Guimarsta0onradiosondesoundings.IACGPS.InternalTMTanalysis

CMTlogs,Garcia-Gilletal.,2010

IAC,NOT SteidelObs.(M.Pedani,2004,NewAr)

RawdataCMT.InternalTMTanalysisPlusLT,StetsonObs,SteidelObs.

RawdataTNG.InternalTMTanalysis

RawdataNOT.InternalTMTanalysis

GTC,LT,Geminidevelopment,CTAtes0ng

SPM TMTSitetes0ngforCerroPelado,SPM

TMTSitetes0ngforCerroPelado,SPM




- SchusterW.,ParraoL.&GuichardJ.,2002



CTAtes0ng

Honar TMTSitetes0ngforTolonchar

ChajnantorPlateau,Perez&Otárola,2004

ExtrapolatedfromChajnantorPlateau(Giovanellietal.,2001)

ErasmusstudiesandGiovanellietal.,2001

ExtrapolatedfromCBITelescope

- - TMTSitetes0ngforTolonchar

TMTSitetes0ngforTolonchar

-

Mackenna TMTSitetes0ngforArmazones

TMTSitetes0ngforArmazones

TMTSitetes0ngforArmazonesandLakicevicetal.,2016,Kerberetal.,2014,Otarolaetal.,2015

TMTSitetes0ngforArmazonesandParanalASCAM

ExtrapolatedfromTMTSitetes0ngforArmazones

Paranalsitemeasurements

Patat,F.,2004



CTAtes0ngforArmazones


8


!   Sitecharacteris0cs!  Compara0veresults


9


♯FromIMACSuserguide§MedianvalueforArmazones,TMTsitetes0ng$0.132exc.Mt.Pinatuboerup0on

!   Sitecharacteris0cs!  Compara0veresults

Sitecharacteris@cs(medianvalues,unlessstated)

MKO(USA)

ORM(Spain)

LCO(Chile)

Al@tudeofsite(m) 4050 2250 2500Frac@onofyearlyusable@me(%) 72 72 75Seeingat60maboveground(arcsecond) 0.50 0.55 0.50Isoplana@cangle(arcsecond) 2.55 2.33 2.05Atmosphericcoherence@me(ms) 7.3 6.0 5.0PrecipitableWaterVapor(%of@me<2mm) 54 ≥20 23Adap@veOp@csStrehlmeritfunc@on 1.0 0.93 0.92MeannighWmetemperature(oC) 2.3 7.6 13.0Ex@nc@on(Vmag/airmass) 0.111 0.137$ 0.14♯

Grounddustconcentra@on(µg/m³) 0.815 1.006 2.289§


10


!   Sitecharacteris0cs!  Keyresultsandexamples

!  Groundleveldust!  MirrorDegrada0on!  Usable0me!  Ex0nc0on!  PWV!  Op0calTurbulenceandLaserGuideStarOpera0on

!   Publicdocumentsandinforma0on! hop://www.tmt.org/observatory/site-informa0on/alternate-site-studies

Significant funding provided by the Gordon and Betty Moore Foundation

Thirty Meter Telescope

Site Locations

ALTERNATE SITE: OBSERVATORIO DEL ROQUE DE LOS MUCHACHOS

December 2016 www.tmt.org

Alternate Sites

STUDIES


11

Atmospheric Turbulence and

Laser Guide Stars


12

!   Sitetes0nghasbeengoingonfordecadesatORM!   Lotsofdifferentdatasetsavailable!   Nolong-0meMASS/DIMMdatasetfordirectcomparisonwithotherTMTsites

!   Becauseweneedthe60-mseeing,weneedtoworkwithturbulenceprofiles!   DIMMdataareonlyusedfor(successful)consistencychecks

!   Bestavailabledataset:SCIDARdatacovering>5years,almost200,000datapoints! ScidarprofilesareactuallymoreaccuratethanMASSprofilesforAOperformance

analyses(becauseofthehigherver0calresolu0on),butweneedtocomparetoMASSdatafromothersites➞reduceSCIDARdatatoMASSresolu0on

!   Comparisonwithothersitetes0ngdatasetsandAOperformancefromobservatoriesareallconsistent

!   Usingsameextrapola0onto60mseeingasforMaunakea13N!   Thisisdoneonapoint-by-pointbasis,assemblingsta0s0csaYerward

!   Butusingsta0s0csgivesalmostiden0calresults(yes,weverifiedallofthat)!   Alldistribu0onsveryclosetolog-normaloncesufficientdataareavailable

!   N.B:Accuracyof(highquality)turbulencemeasurementsisorder10%

ORM Turbulence Data


13

! Isoplana0cangle:SCIDARprovidesreliablees0mate!   GLdoesnotmaoeratall!   WeuseMASS-resolu0onprofilesfromSCIDARsforcomparisonwithothersites

!   Thereisnoques0onthatthecoherence0meislargeatORM

!   Thishasbeenshownoverandoveragain!   200mbarwindspeed(seebackupslide)!   Weakhigh-eleva0onturbulence!   Consistentwithexis0ngmeasurements

!   No0meseriesofτ0measurementssimultaneouswithSCIDARprofilesavailable

!   Usinges0mateofaverageτ0forallprofilesforAOperformancesimula0ons!   Someuncertaintyonexactvalue,but:

!   ExpectedtobelongerthanattheChileansitesandslightlyshorterthanatMaunakea!   Sensi0vityand“inverse”analysesshowthatthishasasmalleffectonNFIRAOS

performance!   6msisaconserva0vees0matecomparedtoothersites

Isoplanatic Angle and Coherence Time


14

Laser Guide Star Operation

!  ModelingofLGSperformanceincludedex0nc0onandscaoeringeffects!  RayleighScaoering,O3ChappiusBand,Cirruscloudicepar0cles,ex0nc0onandscaoeringduetodust(aerosols)

!  Cirrusathigheral0tudecausesmorebackscaoeringthandustatloweral0tudesforthesamelevelofex0nc0on

!   Ex0nc0onatORM(regardlessofcourse)hassamesta0s0csasex0nc0onatMK13N

!  ConclusionisthatdustatORMwillnotsignificantlyaffectLGSopera0on


15

Dust. Usable Time. Extinction.


16

Sources of ground level dust measurements

!  MK13N,Tolonchar,SPM,Armazones!  ~2.5yearsateachsite!  Measurementsevery5to7minutes!  Commercialdustsensorat7m

!  ORM!  9years5monthsofmeasurements!  Measurementsevery2hours!  Externalinletat11monTNGenclosure!  Commercialdustsensor(differentmodelbutsamespecsasabove)


17

Dustmassconcentra0onprobabilitydistribu0on(Dustmasscalculatedfrompar0clesizedistribu0on)•  ORMandMK13Nhavelowesttypicaldustlevels

TMT.PSC.TEC.16.007.DRF01 Page 38 of 51 ASSESSMENT OF ALTERNATE SITES FOR TMT, METHODS AND RESULTS

October 13, 2016 Table 18: ≥15 µg/m3 is considered a dust event at ORM9, the GTC cleans mirrors in response. If the level reaches 50 µg/m3 and continues rising the LT prepares to close. 100 µg/m3 is the GTC and LT operational limit.

Fraction of time exceeding Site Median µg/m3 ≥15 µg/m3 ≥50 µg/m3 ≥100 µg/m3 ORM 1.006 11.5% 2.3% 0.54% MK 13N 0.815 6.8% 3.6% 2.4% SPM 7.02 26.8% 13.9% 4.4% Armazones 2.29 5.4% 0.41% 0.32% Tolonchar 6.30 24.7% 8.9% 2.1% Tolar 3.38 13.1% 0.30% 0.11%

The ORM observatories close when dust levels reach unacceptable levels, typically the closure limits are 100 µg/m3. To explore the operational issues related to the fractions of time the dust levels were above various thresholds were calculated for all sites, these are shown in Table 18. Figure 14 shows zoomed in portions of the dust mass concentration time series for the TMT candidate sites. A common misconception is that only ORM is seriously affected by the presence of dust. In Figure 14 it is evident that the dust levels at sites other than ORM are not necessarily any better and Table 18 quantifies the occurrence of various dust levels. Surprisingly, the occurrence of dust levels >100 µg/m3, the shutdown level for the GTC and LT at ORM, is 4 times more common at Maunkea 13N than at ORM, 4 times more common at Tolonchar and slightly more frequent than at Tolar and Armazones (at a level <<1%).

Figure 12: Red dots show the correlation between the two methods for estimating the dust mass from the dust particle size distribution (measured dust refers to the 9 Some works suggest that 20 µg/m3 would be considered a dust event; Chiapello et al. 'Detection of mineral dust over the North Atlantic Ocean and Africa with Nimbus 7 TOMS', J. Geophys. Res., 104, (1999), p 9277-9291


18

Ground level dust concentrations

Dashedlinelevelconsideredas‘anevent’atORM(15μg/m3)

DashedlineshowsORMclosurelevels(100μg/m3)

•  ORMandMK13Ntypicallyhaveverylowdustlevels•  Allsiteshaveepisodesofhighdustlevels


19

Mirror degradation

!   Geminites0ngatPachon!   BareAllost0.03%/day,protectedsilver0.06%/daywithoutanycleaning

!   Bothrestoredto100%aYerwetcleaning–nosurfacedegrada0on!   CTAtes0ng(overcoatedAlatSPM,Armazones,Teide)

!   %/day–0.015(SPM),~0.02(Armazones),~0.01(Teide)!   Liverpooltelescope(bareAl)experienceatORM

!   0.1%/dayinbetweenCO2cleaning,0.04%onaveragewithCO2cleaningon6week0mescale–samerateasothersites

!   GTC(bareAl)experienceatORM!   CO2cleaningproceduresensurenoaddi0onalmirrordegrada0onduetodust

!   “Theimpactonopera0onsofgroundleveldustatORMismuchlessofaconcernthananecdotalreportswouldleadonetobelieve.”-TMTInternalreport(W.Skidmore,etal.)


20

Usable Time !   Usable0meatORMises0matedfromobservatoryweatherlosssta0s0cs

!   Shutdowncondi0onsaredifferentfromobservatorytoobservatory(incl.TMT)

!   Usable0meforTMTatORMwilllikelybesimilartothelargetelescopesthere,i.e.,inthe70-74%range(using72%inSMF)

!   Corroboratedby“manual”analysisof5yr1monthofCMT(ATC)observinglogswhichagreeto<2%withvalueintableabove(19.1%vs.20.7%)


21

Usable Time

!   “Clearfrac0on”fromtheErasmussatellitestudies!   Satellitedatacoverlongerperiodsthanon-sitemeasurementsatthesites!   Satellitemeasurementsextensivelyvalidatedusingon-siteall-skycamera

(ASCA)andMASStransparency,weathersta0on)!   Addi0onal0melostcomesfromsimultaneousASCAandweathersta0on

measurements!   Useofsatellitedatameansthatwehaveequivalentdataforallsites!   Rela@veprecisionforcomparingsitesin2008reportis5%orbe^er

Clear Fraction

Additional time lost due to weather

Usable Time Best Estimate

ORM 72% SPM 82% 2% 80% Armazones 89% 3% 86% MK 13N 76% 4% 72% Tolonchar 82% 3% 79%


22

Extinction

ModelsbyChuckSteidel(Consistentwithhiscalibra0onmeasurementsatORMandMK)nMedianex0nc0onlevelsfrom10yearsofnightlyphotometriccalibra0onmeasurementsfromLiverpoolTelescope✕0.132mags/airmassfrom30yearsofCMTmeasurements,excludingthepartofhighex0nc0onduetoMountPinatuboTriangleisVbandex0nc0ononGeminiNorthwebsiteof0.12mas/airmass


23

C.Butonetal.,2013


24

Precipitable Water Vapor Site ORM SPM Paranal

(Mackenna) Maunakea Honar

Al0tude 2250m 2830m 2640m 4050m 5400m

<2mm 20% 26% 44%(50%)

54% 76%

5% 1.02mm 1.06mm 0.81mm 0.59mm 0.16mm

10% 1.42mm 1.29mm 0.99mm 0.78mm 0.23mm

20% 2.00mm 1.74mm 1.32mm 1.03mm 0.34mm

25% 2.20mm 1.96mm 1.46mm 1.15mm 0.40mm

50% 4.24mm 3.12mm 2.26mm 1.91mm 0.80mm

75% 7.03mm 6.12mm 4.04mm 3.54mm 1.74mm

95% 12.2mm 15.15mm 9.58mm 8.15mm 5.12mm

ORMPWVderivedfromRadioSondemeasurements.PublishedGPSmeasurementsbelievedtobeunder-es0mate.<2mmvalueforMackennaes0matedasevidencesuggestsPWVscaleheightis>1.8kmatgroundlevelbutdoesn’tprovidequan0ta0vevalue.


25

Climate Change

!  Dr.EddyGraham!  HadleyCellsaremovingandexpanding

! Noevidencethatchangeswillaffectthepoten0alTMTsites

!  Someotherexis0ng/poten0alsitesmaybeaffected!  Equatorialregionsbecomingpoorerhigh/lowerla0tudesimproving

1

TMT Climate Study Contract No. TMT.BUS.CON.16.___.REL01

Final Report

This document version: 1.0 This version supersedes any earlier version. Date: 16 October 2016

Dr. Edward Graham (FRMetS) Meteorologist and Climatologist @eddy_weather Scotland


26

Available observing modes and ability to support science

!  Abilityofpoten0alsitestosupportTMTscienceTMTpoten@alsites

Al#tude(m)

MKO(4050)

ORM(2250)

SPM(2790)

Chile#1(5400)

Chile#2(3110)

%ofusable0meforscience 72 72 80 79 86

Sciencecases

Visiblespectroscopy/imaging WFOS

UV/VisibleHRspectroscopy WFOS

Near-IRAO IRIS/NFIRAOS,PFI

L/M/Nbandobserva0ons MICHI

Q-band MICHI

Maincharacteris@csPros

(Benchmark)AOperf. %clear@me UV/Mid-IR %clear@me

Cons Mid-IR Mid-IR Weather N/A

SiteM

erit

Func@o

n

Visible 1.0 0.9 0.9 1.1 1.2

Near-IR 1.0 0.8 0.8 1.1 1.0

Mid-IR 1.0 0.2 0.3 2.6 0.8

[40%Vis.,50%Near-IR,10%Mid-IR]Total 1.0 0.8 0.8 1.2 1.0

(notTMTcore-science)


27

Assessment against science cases

Color coding(sensitivity wrt MKO): Better Identical Acceptable Compromised Important loss Target problems (loss of targets, or challenging observing conditions due to site latitude)

New science cases from 2015 DSC

Observing U.S.A. MEXICO SPAINWavelength Spectral Image MKO SP.Martir vs MKO R.Muchachos vs MKO Honar vs MKO V. Mackenna vs MKO

(µm) (λ/Δλ) Resolution (mas)

Strehl (S) / Contrast (C) ratio (4050m) (2800m) (2250m) (5350m) (3100m)

100% 108% 99% 105% 117%

Dwarf galaxy SL 0.51-0.535 >20,000 10000 WFOS All sites+/- equal at these Dwarf galaxy MCAO 2 - 2.4 6 10 (20) > 0.3 (20) 10000 (20) 100-1000 (20) Ideally WIRC, IRIS All sites+/- equal at

Baryonic SL 1000(2) 280000 (2) 1000 (2) WFOSBaryonic SL 5000 (2) 12800(2) 80(2) WFOSGalactic MCAO 2 - 2.4 > 3000 (23) < 15 (23) 100 120 Ideally IRIS but WIRC Galactic Center science

Lyman-alpha SL 0.35 - 0.62 1000 - 5000 800 (2) 12800 - 80 - 1000 (2) WFOS, same Low altitude sites loose Supernovae MCAO 1.5 - 1.7 (21) 4000 (21) 250 (21) 250 (21) 250 SNIa at 1 < z < All sites+/- equal at these

SL 0.30 - 0.90 7500 (17) 700 (17) WFOS Low altitude sites loose MCAO 0.97 - 1.8 (16) 30000-50000 NIRES All sites+/- equal at these

Supernovae SL/MCAO (18) 0.3 - 2.5 (18) 1000-5000 200 - 500 (18) 40 - 250 (18) WFOS/IRIS Low altitude sites loose Tidal flares SL 0.30 - 0.90 7500 (17) 700 (17) 2000 2000 WFOS Low altitude sites loose

SL 0.49-0.59 (3) 50000 (3) 700 (3) 50 (3) 50 (3) HROS All sites+/- equal at **NEW DSC** Dark Matter MIRAO MIR >300 ~4 ? MICHI IFU or Imager All low altitude sites have

Primordial MCAO/MOAO 1.6 - 6.0 3000 (8) 25 (10) 25 - 250 25 (10) IRMS/IRMOS/IRIS Thermal-IR sensitivity Characterizin MCAO/MOAO 1.1 - 1.6 3000 (8) IRIS/IRMOS All sites+/- equal at these Topology of MOAO 0.8 - 2.5 (10) ~3000 25 (10) 150 - 1500 (10) 150 (10) IRMOS, R=10Mpc All sites+/- equal at these

MCAO 0.9 - 1.3 30000 NIRES All sites+/- equal at these

SL 0.31 - 1.0 5000 (17) 800 (17) 100 (17) 8 (17) WFOS Low altitude sites loose MCAO/MOAO 1.0 - 2.5 3270 200 100's 10's IRMS/IRMOS All sites+/- equal at these MCAO/MOAO 1.0 - 2.5 4800 8 S = 0.5 (7) 1400 (10) < 140 (10) IRIS/IRMOS All sites+/- equal at these

SL 0.31 - 0.60 5000 800 (17) 15000 100 WFOS w/ HROS follow-Low altitude sites loose SL 0.32 - 0.65 500 800 (17) 120000 1000 WFOS w/ IRMOS Low altitude sites loose

MCAO/NGSA 0.8 - 2.5 (8) 4000-8000 10 (7) S = 0.5 (7) 340 (7) 340 (7) IRIS, sample size is MCAO/NGSA 0.8 - 2.5 (7) 3000 (8) 8 - 10 (7) S = 0.5 (7) 90 (22) 180 (22) IRISMOAO/MCAO 0.8 - 2.5 (11) 4800 (11) 50 (11) S = 0.5 (11) 1200 (11) 35 (11) IRMOS/IRIS All sites+/- equal at these

SL 0.33 - 0.9 (3) 40000 700 (3) 100 100 HROSSL 0.45 - 0.68 90000 700 (3) HROSSL 0.33 - 0.9 (3) 50000 500 (3) HROS

MCAO 1.4 - 2.4 (16) 40000 (16) NIRES - molecular Diffusion SL 0.55 - 0.69 HROS - abundances Mass loss SL 0.4 - 0.7 WFOS - brightest

MCAO 1.0 - 2.5 4000 10 - 30 (20) S = 0.6 (7) 2500 / obs (20) 50 / galaxy IRIS/WIRC

Initial mass MCAO 1.0 - 5.0 (8) 4000 15 S = 0.5 (7) IRIS IFU w/ Structure and MIRAO 4 - 5 (15) 100000 80 100 (15) 100 (15) MIRES/NIRES

Gas MIRAO 4 - 25 (15) 30000 - 300 (15) 300 (15) MIRES/NIRES All low altitude sites have Gaps MIRAO 4 - 13 (15) 100000 400 400 MIRES/NIRES All low altitude sites have

Pre-biotic MIRAO 18 - 25 (15) 100000 (15) 100 (15) 100 (15) MIRES All low altitude sites have

Planets SL 0.48 - 0.62 50000 (3) 700 (3) 100's 100's HROSTerrestrial MCAO 0.97 - 1.7 (16) 50000 - S = 0.3 - 0.6 (16) 400 400 NIRES

Self-luminous ExAO 1.63 (14) 5 (14) 30 (14) S = 0.9 (14) 100's (14) 100's (14) PFI All sites+/- equal at these Reflected ExAO 1.63 (14) 5 (14) 50 (14) S = 0.9 (14) 1900 (14) 1900 (14) PFI All sites+/- equal at these **NEW ExAO 5-10 mic High-contrast / All low altitude sites have Jovians ExAO 1.1 - 1.8 (14) 50 - 100 (14) 50 (14) S = 0.9 (14) PFI/IRIS All sites+/- equal at these Jovians SL 0.5 - 0.9 50000 700 (3) HROS

Oxygen on SL 0.76 - 0.77 40000 700 (3) < 2500 < 2500 HROS**NEW ExAO 5-10 mic High-contrast / All low altitude sites have

Kuiper Belt MCAO/NGSA 1 - 2.5 1000 7 (19) S = 0.3 (19) 1092 (19) 1092 (19) IRIS/WIRC All sites+/- equal at these Composition MCAO/MIRAO 3 -5 (16) 100000 (16) 27 (16) 100 (16) 100 (16) NIRES Thermal-IR sensitivity

MCAO/NGSA 0.8 - 2.5 (19) 2000 7 S = 0.7 (19) 25 (19) 25 (19) Program includes All sites+/- equal at these MIRAO 10 100000 (15) 80 MIRES All sites+/- equal at

M31 / M33 are not visible from Southern

Formation of stars and planetsDSC 8

Ratio of clear nights (wrt MKO)

Low altitude sites loose sensitivity towards short

Our Solar SystemDSC 10

Outer Solar System

Surface physics of Jovian Atmospheric physics of

Direct detection and characterizati

ExoplanetsDSC 9

Doppler detection of

Physics of star

Protoplanetary disksDSC 8.3

Multiplexed spectroscopy of Spatial dissection of forming IGM: Core samples during

Epoch of galaxy formation in

Chemical evolution in the Local Group galaxies and

SMBHs in nearby galactic

Stellar astrophysics

Reconstructing star

Exploration of nearby galaxiesDSC 7

Probing oldest stars in the Looking deeper: isotope

SMBHs at very high redshift

Gamma-ray bursts

Variation of fundamental

Science Program

Nature of Dark Matter

DSC 3.1

Extragalactic SuperMassive Black Holes

Early UniverseDSC 4

First GalaxiesDSC 4.3

Dark energyDSC 3.2

Physics of extreme objectsDSC 3.3

Intergalactic medium

0.35 - 0.62 (2) 800 (2)

Sample Size Comments# of observation

s

Comments

Southern sites mean loosing Kepler targets but

Southern sites mean loosing Kepler targets but

SL/NGSAO/ MCAO/

MOAO/MIRAO/ExAO

Spectral Parameters Spatial Parameters Multiplexing

600600

Differential impact of alternative sites wrt MKOCHILE

Galaxy Formation

and Intergalactic

medium

Multiplexed spectroscopy of

(Exo-) Planetary

atmospheres

SMBHs beyond local

Note: (1) UV and near-IR sensitivity impacted for low altitude sites. (2)

Southern sites mean loosing M31 and other

N.H. galaxies but getting access to Magellanic

Fundamental Physics and CosmologyDSC 3

M31 / M33 are not visible from Southern

AllalternatesitesareabletosupportTMTkeyscience


28


!   Siteevalua0onwasamul0-dimensionprocess:!   Astronomicalproper0esofthesites–AbilitytosupportTMTscience!   LegalstatusforTIOtooperateinthehostcountry!   Processesand0mescalesforobtainingnecessarypermits,scheduletostartconstruc0on!   Costtoconstructandoperate!   Anevalua0onoftheriskstoscheduleandcost.

!   Oct.31st2016,TIOBoardselectedORMasthealternatesiteforTMT.Considering:!   Thescien0ficimportanceforTMTtobeuniquelylocatedintheNorthernHemisphere,securingfullskycoverage

incombina0onwiththeELTprojectslocatedintheSouthernHemisphere.!   TheverygoodqualityoftheORMsite,whichcansupportTMTcorescienceprograms

!  Inpar0culartheturbulenceproper0esandcapabili0esforAOperformance!   Theprogramma0cadvantageswiththeORMsiteincluding:

!  Shorter0melinetoini0ateconstruc0on!  Shorter0melineto‘first-light’!  Lowercostsofconstruc0onandopera0ons!  Lowerprojectrisksbasedonexistenceofsupportinfrastructure

!   ORMisthebestsiteamongallalternatesitesconsidered,tosecureacompe00vepathtofirst-lightwithintheTMTbudgetenvelope

!   Lower-al0tudesiteslikeORMsufferfromlowersensi0vityatlongermid-IRwavelengths,hencelowerefficiency!   Opera0onsschedule(technicalandscien0fic)willbeflexibletoop0mizebestcondi0onsfordemanding

scienceprograms!   Revisi0ngthepriori0esforTMTnextgenera0oninstruments


29

Adjusted operations

!  ORMopera0onsmodelsimilartoMKO!  Maintenancecrewtravelingdailytosummit!  Scienceopera0onsdoneremotelyfromscienceHQ(Tenerife)andTIOsciencenodes

!   Toop0mizescienceefficiency,flexibleschedulingofscienceandengineeringac0vi0esisneededatanysite!  ExtraemphasisisneededatORMtou0lizethebestcondi0onsforthescienceprogramsthatneedthem!  SCMStoincludePWVmonitoring(collabora0onwithIAC)!  Requiresaddi0onalsoYwaredevelopment(wrtcurrentplan)toop0mizereal-0mepriori0za0onofprogramscheduling/execu0on

!   Instrumentpriori0estoberevisited


30

Any questions?

tmt on la palma or maunakea

Documents