cwi procedure version 31 4/3/16 7:50:00 pm cosmic web ......• cwi is sensitive enough to pick up...

CWIProcedure Version31 4/3/167:50:00PM

of 47

CosmicWebImagerUser'sGuideVersion31,April3,2016

MattMatuszewski,PatrickMorrissey,DonNeill,AnnaMoore,ChrisMartin,NinaBudaeva

1. INTRODUCTION..............................................................................................................................4

2...................................................................................................................................................................6

2.1.1. COMMANDLINEVS.GUI...............................................................................................................................62.1.2. LATERALIMAGEALIGNMENT......................................................................................................................62.1.3. SPECTROGRAPHINTERNALFOCUS.............................................................................................................62.1.4. GRATINGANDCAMERASETTINGS...............................................................................................................72.1.4.1. BlueGratingConfiguration................................................................................................................72.1.4.2. RedGratingConfiguration.................................................................................................................82.1.4.3. YellowGratingSettings.......................................................................................................................92.1.4.4. MEDREZGratingSettings...................................................................................................................92.1.4.5. WavelengthVerification.....................................................................................................................92.1.4.6. GratingEfficiencyPeaking(EngineeringTask).....................................................................102.1.4.7. GhostLocation.....................................................................................................................................112.2. OBSERVING....................................................................................................................................122.2.1. OBSERVINGLOG..........................................................................................................................................122.2.1.1. WhattoRecordandHow................................................................................................................122.2.1.2. LogExample..........................................................................................................................................122.2.2. PREPARINGFOROBSERVATIONS..............................................................................................................142.2.2.1. GeneralApproach...............................................................................................................................142.2.2.2. TargetandInstrumentSettingsList...........................................................................................142.2.2.2.1. StandardObservations.................................................................................................................142.2.2.2.2. NodandShuffleObservations...................................................................................................142.2.2.3. CalibrationStrategies.......................................................................................................................142.2.2.3.1. Photontransferdata(onceperrun)......................................................................................142.2.2.3.2. Biases(eachafternoon,morning,andafewthroughoutthenight).........................142.2.2.3.3. Longcalibrationsequences(foreachinstrumentsetting,eachafternoon).........152.2.2.3.4. Domeflats(foreachinstrumentsetting,eachafternoon)............................................152.2.2.3.5. Shortcalibrationsequences(foreachinstrumentsetting,duringthenight,asneeded) 152.2.2.3.6. Spectrophotometricstandards.................................................................................................162.2.2.3.7. Detectordarks(Optionaleachafternoon)...........................................................................162.2.2.4. CenteringTelescopeonCWIIFUandGuider-IFUOffset...................................................162.2.2.5. FocusingtheTelescope....................................................................................................................172.2.3. NIGHT-TIMEOBSERVATION.....................................................................................................................172.2.3.1. Logs...........................................................................................................................................................18


of 47

2.2.3.2. ScienceTargetAcquisitionafterSlewing.................................................................................182.2.3.3. ScienceTargetAcquisitionafterLongornearbyExposure.............................................182.2.4. STANDARDOBSERVATIONS.......................................................................................................................192.2.5. NOD-AND-SHUFFLEOBSERVATIONS.......................................................................................................202.2.5.1. Streamlinedmethod..........................................................................................................................202.2.5.1.1. Streamlinedmethodsetup..........................................................................................................202.2.5.1.2. Streamlinedmethodinvocation...............................................................................................202.2.5.1.3. Streamlinedmethoddiscussion...............................................................................................202.2.5.2. ManualMethod–EXPERTUSEONLY........................................................................................222.2.5.2.1. QuickVersion....................................................................................................................................222.2.5.2.2. LongVersion.....................................................................................................................................222.2.5.3. Abortinganexposureandresettingthesystem...................................................................25

3. ENDOFNIGHT(THINGSTODOATTHEENDOFEACHNIGHT)....................................26

3.1. PARKTELESCOPE..........................................................................................................................263.2. COPYMISCELLANEOUSFILES.......................................................................................................263.3. TRANSFERDATATOBEACH...........................................................................................................263.4. TRANSFERDATATOSRL.CALTECHANDGUESTOBSERVER’SREPOSITORY,IFAPPLICABLE......263.5. PLUGINTHEGRATINGROTATORENCODERIFITWASUNPLUGGED...........................................263.6. PARKALLMOTORS(IMPORTANT!).........................................................................................263.7. CHECK/TURNOFFCALIBRATIONLAMPS......................................................................................26

4. ENDOFINSTRUMENTRUN(THINGSTODOATTHEENDOFTHELASTNIGHT)...26

4.1. GOTHROUGH“ENDOFNIGHT”ACTIONS.....................................................................................264.2. TRANSFERSCRIPTDIRECTORY....................................................................................................264.3. POWERDOWNTHEINSTRUMENT(OBSERVATORYSTAFF).......................................................26

5. APPENDIXI–OBSERVER’SREFERENCE...............................................................................28

5.1. GENERALCOMMENTS....................................................................................................................285.2. AFTERNOON...................................................................................................................................285.2.1. BEFOREDOMEISDARK.............................................................................................................................285.2.2. AFTERDOMEISDARK................................................................................................................................285.3. EVENINGTWILIGHT......................................................................................................................285.4. NIGHT............................................................................................................................................295.5. MORNINGTWILIGHT.....................................................................................................................295.6. MORNING.......................................................................................................................................29

6. APPENDIXII–COMMANDGLOSSARY...................................................................................30

6.1. CONFIGURATIONCOMMANDS.......................................................................................................306.2. MODECOMMANDS.........................................................................................................................326.3. CALIBRATIONCOMMANDS............................................................................................................326.4. EXPOSURECOMMANDS.................................................................................................................346.5. GUIDERCOMMANDS......................................................................................................................35


of 47

6.6. INFORMATIONALCOMMANDS.......................................................................................................366.7. DRAGSTAR.TCL[NOTTESTEDRECENTLY]...........................................................................376.8. APPENDIXIII–ALPHABETIZEDCOMMANDLIST........................................................................38

7. DETERMININGCONFIGURATIONSANDMAKINGCONFIGFILES..................................40

8. APPENDIXIII–AUXILLIARYPROGRAMS...........................................................................41

8.1. CWI_SETTING.PRO...................................................................................................................418.2. CWI_CENTER_STAR.PRO........................................................................................................428.3. CWI_COMPARE_ARC.PRO.......................................................................................................448.4. CWI_GUIDER_OFFSET..............................................................................................................458.5. CWIDS9REGIONTEMPLATEFILE......................................................................................46


of 47

1. INTRODUCTIONTheCosmicWebImager(CWI)isaUV-visibleintegralfieldspectrographfortheCassegrainfocusoftheHale200"telescopeatthePalomarObservatorywithafieldofviewof60"x40".Theinstrumentspatialresolutionisseeing-limited(~1")alongtheslicesintheshortdirectionandslitlimited(~2.5")inthelongdirection.TheinstrumentisboltedtotheCassegrainrotatorandthefieldofviewcanberotatedonthesky.

CWIhasananticipatedwavelengthcoveragefrom380nmto800nm(limitedbyCCDfringing)withresolvingpowerR~5000.AsofAugust2014CWIfourgratingsareavailableforusewithCWI.TherearethreeR~5000volume-phase-holographictransmissivegratings.TheBLUEGratingcovers460to550nm,YELLOWfrom555to690nm,andREDfrom640to770nm.Asub-rangeoftheseisavailableatanysinglesetting(approximately45nmfortheblue,50nmfortheYELLOW,and55nmfortheREDinfullCCDmode,and1/3ofthatinnod-and-shuffle).Additionally,thereisanR~2000surface-reliefreflectivegratingthatcanaccess380to600nm,withinstantaneouscoverageofabout100nm,1/3ofwhichwouldbevisiblewiththenod-and-shufflemaskinplace.ThisMEDREZgratingisnotyetwellcharacterized;itisslightlysmallerformatandthus,likely,lowerefficiencythanthefullVPHgratings.KeyCWIparametersarelistedinTable1.

Thenod-and-shufflemaskisretractable;theinterchangerequiresapersonfamiliarwiththeinstrumentandtakes,roughly,30minutes.

Theinstrumentiscommandedthroughatcl shellinterface.Thisisusedtosetexposuretimes,initiatecalibrationexposures,configuretheinstrument,commandtheguider,starton-skyexposures,etc.Forreasonsthatarebeyondthescopeofthisdocument,muchoftheinstrumentconfigurationisnotrecordedinimageheadersbutinseparate“.info”files.ThesefilesareonlygeneratedwhenexposuresarecommandedthroughtheCWItclinterface.

AdatareductionpipelineisbeingdevelopedfortheKCWIinstrumentthatisapplicabletotheCWIdatacubes.ThepipelinecanbeobtainedbycontactingDonNeill([email protected]).

NotaBene:

• Itisalwaysgoodtohaveaflashlighthandywheneverincageanddome• CWIissensitiveenoughtopickupambientlightwithinthedome,especiallyduringlong

exposures.Forobservationsofveryfainttargetsitisagoodideatocheckforanyremaininglightinsidedomebeforeopeningthedomeafteradaptingeyestothedark.

THEFOLLOWINGISIMPORTANT.ALLMOTORSTAGESSHOULDBERETURNEDTOTHEIRZEROPOSITIONBEFORETURNINGOFFTHEMOTORCONTROLLER.THISISDETAILEDBELOW.FAILURETODOSORESULTSINARE-ZEROINGOFTHEMOTOR/SINANON-ZEROLOCATIONWHENTHECONTROLLERISPOWEREDONAGAIN.THISMEANSLOSSOFCALIBRATION.


of 47

Table1.CWIParameters

Parameter Value NotesField-of-view 60x40”

Field-of-viewformat 242.5”x40”slits Spatialresolution 2.5“xSeeing(~1”) Accessiblespectral

range(blue)4600Åto5500Å G’filter,abitfurtherred

withther’filterinstalled.Singlesettingspectral

range(blue)450Å120Å

FullCCDNod-and-Shuffle

Accessiblespectralrange(yellow)

5560Åt6900Å r’filter

Singlesettingspectralrange(yellow)

500Å140Å


Accessiblespectralrange(red)

6460Åto6900Å6900Åto7700Å

r’filteri’filter

Singlesettingspectralrange(red)

570Å170Å


Spectralresolution 5000 λ/ΔλGuiderfield-of-view 3’x2’ PalomarautoguiderGuidersensitivity V~17 Palomarautoguider

Readnoise <3e 2.5e(typical)Detectorgain 0.145 e/DNRead-out-time 100s Singleamplifier

Throughput(blue) 10% Includingsky+telescopeThroughput(yellow) 10% Estimate,incl.sky+telescopeThroughput(red) 10% Includingsky+telescope


of 47

2.

2.1.1. COMMANDLINEVS.GUITheCWIinstrument,includingthedetector,shouldbecommandedfromtheCWITCLshell.WhileitispossibletousethedetectorGUItotakeimages,thatapproachdoesnotleadtoallthedataneededforthedatareductionpipeline(DRP)beingstored.

2.1.2. LATERALIMAGEALIGNMENTWheneverthedetectordewarisservicedoutsidetheinstrument,orgratingsareexchanged,thespectramightshiftslightlyinthespatialdirection.AtiltofFoldMirror4(FM4)willcorrectforresultingmisalignment.

AppropriateFM4settingsfortheblueandredgratingshavebeendeterminedandcanbesetbyinvoking“CWI>RedSettings”,“CWI>BlueSettings”,“CWI>YellowSettings”,“CWI>RichSettings”fromtheCWItclprompt.ItshouldbenotedthatthisalsoadjuststheFM2position(i.e.,focus).

Arotationby+200RPmotorstepsshiftsthespectrumby~64unbinnedCCDpixelstotheright.

2.1.3. SPECTROGRAPHINTERNALFOCUSThespectrographmustreimagetheimageslicerontothedetector.Thisimagemustbeinfocus.Thefocusadjustmentisdonebytranslatingoneofthefoldingflatsintheinstrument,FM2,alongtheopticalpath.Thisaltersthepathlengthfromtheslicertothecollimatormirror,whilekeepingthecollimatormirrortothecameralensdistancefixed.

Thebestspectralfocuspositionshavebeendeterminedfortheblue,red,yellow,andRichardson(MedRez)gratings.TheCWItclshellcommands“CWI> RedSettings”,“CWI> BlueSettings”,“CWI> YellowSettings”,and“CWI> RichSettings”moveFM2tothosevalues.ItshouldbenotedthatthesealsocommandFM4toapositionthatcentersthespectralaterallyonthedetector.

Theopticaldesignhasslightastigmatism,andthebestspectralfocusisatadifferentFM2locationthanthebestspatialfocus.Atthetimeofthiswriting(July2012),thebestinstrumentspectralfocushasbeenfoundatRPencoderreadingforFM2of+140,000.

• Atclprocedurefm2_focus.tclhasbeenwrittentotakeasetofarclampimagesatvariousFM2locations;thisprocedureshouldnotberanveryoften,infact,itprobablydoesn’tneedtoberanatallanymore,unlesssomethingoddhappens.

TheprocedurestepsthroughpossibleFM2positionsincoarsestepsandtakesarclampimages.Thesecanthenbeinspected(manually,orautomatically)tofindthebestfocuslocation.


of 47

Thedatasetconsistsofroughly10images,andthelengthoftimerequiredwilldependonthereadoutmode.TheslowestCWIreadoutmodewillrequireabout30minutes.Thescriptgeneratesanoutputlogfilefm2_focus.dat,whichcontainstheimagenumbersandcorrespondingstagepositions.

2.1.4. GRATINGANDCAMERASETTINGSThegratingandcamerapositionsmustbesettoselectthedesiredwavelengthrangeandtomaximizetheinstrumentefficiency.TheencoderreadingsinthissectionarecontingentonproperhandlingoftheCWImotorcontrollersandstages,i.e.,parkingthembetweenusesandensuringthatpositionsareproperlyrecoveredafteranypoweroutages.

Whenusingatabulatedconfiguration,itisrecommendedthatthesettingbeverified.Whenusinganinterpolatedvalue,itisagoodideatobothverifythesettingandtoensurethatthegratingefficiencyispeakedandnoghostslieonimportantpartsofthespectrum.

Thearticulationstagetravellimitsare+290,000and–1,700,000.Notethatthesettingsbelowshouldbeverifiedeverytimeagratingchangeismade.Somecareshouldbetakenwhencomingclosetoeitherlimit.

AmethodforconfiguringnewsettingsisdescribedindetailinSection7onpage40.

2.1.4.1. BlueGratingConfigurationTable2showsthepreconfiguredsettings,whiletheequationsthatfollowallowtheusertocomputegratingandcamerapositionsforotherwavelengthsofinterest.Theaccessiblewavelengthrangeislimitedbytheminimumangleofincidencethatthearticulationstagecanbecommandedtoontheblueside(4500Å),andbythefiltercut-offwavelengthontheredside(5400Å,5600Åwithoutfilter).Thearticulationstagetravellimitsare+250,0001and–1,700,000.Notethatthesettingsbelowshouldbeverifiedeverytimeagratingchangeismade.

Table2.BlueGratingConfigurationSettings

CentralWavelength

GratingSetting

CameraSetting

DateVerified

Notes

4680Å 8,000 180,000 12/05/2012 4862Å 4,600 -115,000 12/05/2012 4935Å 2,450 -235,000 12/05/2012 4984Å 600 -315,000 12/05/2012 5005Å 0 -350,000 ? 5207Å -6000 -700,000 ? 5527Å -14500 -1,300,000 ?

1140526–Theactuallimitis+290,000,butthatisveryclosetoahardstop.Besttoavoidgoingthatfar,butcanifnecessary.Centralwavelengthforthisvalueis~4605Å


of 47

Asimplequadraticwasfittotheabovepoints:

GRATING=1985.42λ10002–48421.28λ1000+192442.81,CAMERA=-264292.78λ10002+963054.31λ1000+1450808.62,

whereλ1000isthewavelength,inangstroms,dividedby1000.

AnIDLprocedure,cwi_settings.pro,returnsthegratingandcamerasettingswhenitisgivenalistofcentralwavelengths.Note,asof140526thesolutionsaboveappearabout+10Åofffromtheactualcentralwavelength.Itispossiblethatinthepastwewerenotassensitivetomisalignmentsofthisscaleanddidnotnoticethem.

2.1.4.2. RedGratingConfigurationTable3showsthepreconfiguredsettings,whiletheequationsthatfollowallowtheusertocomputegratingandcamerapositionsforotherwavelengthsofinterest.Theaccessiblewavelengthrangeislimitedbytheminimumangleofincidencethatthearticulationstagecanbecommandedtoontheblueside(6400Å),andbythefiltercut-offwavelengthontheredside(7000Å,7700Åwithoutafilter).

Table3.RedGratingConfigurationSettings

CentralWavelength

GratingSetting

CameraSetting

DateChecked

Note

6500Å 8,000 +250,000 20/07/2012 Hα(6562Å) 5,500 180,000 11/05/2012 CenteredonHα6640Å 4,400 116,000 11/05/2012 LinesfitinN+Sconfig,

Hα(6562Å),SII(6716Å),NII(6583Å)

6740Å 3,000 0 20/07/2012 6895Å 0 -180,000 20/07/2012 7045Å -3,000 -350,000 20/07/2012 Filtercut-offaround7000Å

Asimplequadraticwasfittotheabovepoints:

GRATING=2842.68λ10002–57413.39λ1000+260526.19,CAMERA=-21108.91λ10002+1754184.88λ1000–2237841.50,

whereλ1000isthewavelength,inangstroms,dividedby1000.

• AnIDLprocedure,cwi_settings.pro,returnsthegratingandcamerasettingswhenitisgivenalistofcentralwavelengths.


of 47

2.1.4.3. YellowGratingSettingsAsofAugust2014,CWIisequippedwitha“yellow”gratingdesignedtoworkinthegapwavelengthsbetweentheblueandthegreen(5560to~6800Å).AsoflateAugust2014thereddestpartofthewavelengthrange(outtocamerasettingof-1,700,000)hasnotbeenexplored.ThefullCCDwillcontainabout550Å,and1/3ofthatwillbeavailableinN+S.

Table4.YellowGratingConfigurationSettings

CentralWavelength

GratingSetting

CameraSetting

DateVerified

Notes

5590Å 6,200 250,000 23/08/2014 5785Å 2,000 0 23/08/2014 5968Å -2,500 -250,000 23/08/2014 6150Å -7,000 -500,000 23/08/2014 6320Å -10,000 -750,000 23/08/2014 6481Å -15,000 -1,000,000 23/08/2014

2.1.4.4. MEDREZGratingSettingsNotethatthisdataisVERYPRELIMINARY.Wedon’thaveagoodideaofthethroughputhere,thoughitseemsOK,orifthegratinganglesareoptimized.Herearesomesettings,non-the-less!Infull-ccdmode,wecanfitabout900Åatonce,1/3ofthatinN+Smode.Thecentralwavelengthvaluesforthisgratingarequiteapproximate.

CentralWavelength

GratingSetting

CameraSetting

DateVerified

Notes

4300Å -237,500 -1,710,600 25/08/2014 Seriousefficiencylossbelow3900Åandnocont-lampflux

4950Å -242,500 -1,710,600 25/08/2014 5400Å -246,500 -1,710,600 25/08/2014 5900Å -250,500 -1,710,600 25/08/2014 6300Å -254,500 -1,710,600 25/08/2014 Dubiousefficiency.

2.1.4.5. WavelengthVerificationWavelengthverificationiscurrentlyperformedmanually.Thisis,obviously,notideal.

• AnIDLprogramhasbeenwritten(cwi_compare_arc)whichtakestheimagenumberofanarcexposure,thenameofthegrating,(/redor/blueor/yellowor/medrez),andwhethernod-and-shufflemaskwasin(/ns).Thiscanberanfrombeach,oryourpersonalunix-likeidl-enabledcomputer.

• e.g., cwi_compare_arc, 7481, /ns, /red, /remote• AsampleoutputoftheprocedureisshowninFigure1.


of 47

Figure1.Outputofcwi_compare_arc.Thetopandbottomtwopanelsshowacquiredspectra,whilethecentralpanelisareferencespectrum

2.1.4.6. GratingEfficiencyPeaking(EngineeringTask)Whilethecameraarticulationstagelocationdetermines(tofirstorder)thecentralwavelengthandwavelengthrangefortheVPHgratings,thegratinganglesweepstheefficiencycurveacrossthebandwidth.Oncethegratingandcameravaluesforadesiredwavelengthhavebeenselectedusingdatainsectionsaboveandthecentralwavelengthhasbeenverifiedasexplainedinsectionthegratingoughttobepeaked.Thisisdonebytaking7arclampexposuresatgratingpositionoffsetsof-3000,-2000,-1000,0,+1000,+2000,+3000fromtheestimatedposition.

Itisimportantthatthearclamphashadtimetowarmup,atleast5minutes,beforethefirstexposureinthesequenceistaken.

• IDLroutinepeak_grating.pro,whichtakesthepathandsetofimagenumbersasinput,producesgraphicaloutputthatallowstheusertodecidewhichimageinthesequencepeaksefficiencyatthecenteroftheband.

Thedeterminationisperformedbylookingataspectralpeaknearthecenterofthespectralbandpass,recordinghowthepeaksgrowanddiminishforslices11and12(startingat1).Figure2showstheoutputofthisprogram.ThecenteroftheCCDisshownwithayellowdashedline.Thelegendshowstherelationbetweenimagenumbersandcurvecolors.Arcexposure5899correspondstothehighestefficiency.


of 47

NotethatthebehaviorisdifferentforthesurfacereliefgratingMEDREZ.

Figure2.OutputofIDLroutinepeak_grating.pro

2.1.4.7. GhostLocation[CHECKTHE8ÅNUMBER]

GratingLittrowghostsmayfallonacriticallyimportantpartofthespectrum.Slightgratingrotations,upto800RPcountsorso,willmovetheghostswithoutsacrificinginstrumentefficiency.Achangeingratingpositionof+200countsmovestheghosts-8Å(60unbinnedpixels)atthe4935Åsetting;thusamoveofZÅinwavebandcenteredonλrequiresagratingrotationof:

ROT=-200Z/(8Å)*(λ/4935Å)(RPcounts)


of 47

2.2. OBSERVING

2.2.1. OBSERVINGLOG2.2.1.1. WhattoRecordandHow

Asmuchinformationaspossibleshouldfinditswayintothenightlylog.TheprimarynightlytextlogiscontainedinanExcelspreadsheetandshouldbeasdetailedaspossible.Informationsuchasinstrumentset-up,observers,entryintodome,absolutelyanythingthattellsafuturedatareductionanalystmayfindusefulinformationshouldberecordedhere.Youcanuseyourownlogformat,ifyouprefer,butkeepinmindthedataelementsweliketorecordfortheinstrument.

Alogtemplateisavailableonporgyandbeach.

Attheendofeachnight,priortodatatransfer,thelogmustbeplacedinthenight’sdatadirectoryinthreeformats:xlsx,csv,txt.

MotorpositioninformationisgeneratedautomaticallybytheCWIscriptsandiskeptinthefollowingfile:

/home/cwi/oldporgy/palomar_guider/log.txt

2.2.1.2. LogExample

Figure3.ExampleLogScreengrab

Figure3isascreencaptureofthenewCWIloginExcelformat.Thecolumnsarebrieflydescribedhere:

A.Time.Thewallclocktimetheentryismade

B.Notes.Self-explanatory.Keyentries(grating/filterchanges,etc.)tobemadeinRED


of 47

C.Number.Theimagenumber.

D.Type.Thetypeofimagebeingacquired.Possibletypes:

• Bias• Arc/flat• Arc/bars• Cont/flat• Cont/bars• Star(Standard?)• Object• Background• NSimage• Domeflat• Dark• Test• Other(usersmayenteranyasciistring)

E.Exposure.Exposuretimeinseconds

F.SciTarget.Nameofthetargetbeingobserved

G.&H.SciPointing.The(RA,Dec)ofthetarget

I.BkgTarget.Nameofthebackgroundtargetbeingobserved

J.&K.BkgPointing.The(RA,Dec)ofthebackgroundfield

L.Script.Thenameofthescriptrantotakeexposures

M.&N.Temperatures.TheCCDandColdplatetemperatures.Thevaluescanbeobtainedbyexecuting“CWI>getTemps”fromtheCWITCLcommandprompt.

O.Pressure.ThepressureregisteredatthePiranigauge.ThiscanonlyberecordedwhenthePiranigaugeispluggedin.Thishappenstypicallybeforetherunor,sometimes,intheafternoon.

P.&Q.Stageinformation.ThepositionsoftheCWIstages.Thisinformationcanbeissuing“CWI>rp”and“CWI>tp”commandsattheCWITCLprompt


of 47

2.2.2. PREPARINGFOROBSERVATIONS2.2.2.1. GeneralApproach

PreparingforastronomywithCWIrequiresanumberofset-up,calibrationandalignmentsteps.Thefollowingisanoutlineofthesestepsandactionsgroupedroughlyinchronologicalorder

2.2.2.2. TargetandInstrumentSettingsListItistheObserver’sresponsibilitytohavealistoftargets(includingcoordinates)andinstrumentsettingsready.ThelattershouldbediscussedwiththeCWIteamorobservatorystaffpriortotheobservingdate.

2.2.2.2.1. StandardObservationsForstandardobservationsonlythefieldcoordinatesarenecessary(targetorbackground).Theobservershouldhaveanideaoftheexposuretimesrequired.Oftenaninitial60sexposureisusefulfordecidingonexposuretime.

2.2.2.2.2. NodandShuffleObservationsFornodandshufflepointings,theobservermustpreparethefollowinginformation:

• targetfieldcoordinates• backgroundfieldoffsetinARCSECONDSfromthetargetfield.Thethrowshouldnot

exceed10arcminutes• Totalexposuretimeonthetargetfieldinseconds• Numberofsub-exposurestodividethemainobservationinto.Thesubexposuresought

tobe120sorlonger;shorterexposuresareallowed,thoughtheyleadtolessefficientobserving

2.2.2.3. CalibrationStrategiesThefollowingcalibrationsetsshouldbeobtained,startingwiththeleastfrequent:

2.2.2.3.1. Photontransferdata(onceperrun)Thephotontransferdataisinvokedbycommand:CWI> photon_transfer exposure_time(NOTYETIMPLEMENTED)Whereexposure_timeistheexposuretime(inseconds)neededforacontinuumflattonearlysaturatetheADC(peakaround50kcounts).Itisbetterifthedomeisdark,butnormalmorning/afternoonsituationisOKprovidedtheilluminationconditionsdonotchangesignificantlyandtheCasscagelightsareoff.

2.2.2.3.2. Biases(eachafternoon,morning,andafewthroughoutthenight)

Collect10intheafternoon,asmanyasyouarewillingtositthroughinthemorning.Theseareobtainedbycommanding:CWI> bias NWhereNisthenumbertotake


of 47

2.2.2.3.3. Longcalibrationsequences(foreachinstrumentsetting,eachafternoon)

Thiscollectsanarcflat,arcbars,contbars,and9contflats,strategicallyoffsetfromoneanother.Thewholesettakesabout30minutes.Theusershouldfirstestablishthecorrectexposuretimeforthearcandforthecontinuumflatimage.Neithershouldbesaturated(Exceptfortheoccasionalcosmicray).Idealpeakis45to50kcounts.Thedomeneedstobedarkandtheinstrumentshouldbebuttonedup.Thescriptisinvokedvia:CWI> dayCalib Theexposuretimesaresetautomatically,providedthesettingwasconfiguredusingthenew(Sep2014)cwisetcommand.

Thereisalsoa:CWI> dayCalibShortwhichtakesfewercontinuumflats.Exposuretimesaresetautomatically,providedthesettingwasconfiguredthenew(Sep2014)cwisetcommand.

2.2.2.3.4. Domeflats(foreachinstrumentsetting,eachafternoon)3to5oftheseshouldbecollectedforeachafternoon/evening/followingmorningforeveryrelevantspectrographconfiguration.Thedomeshouldbedark(withtheexceptionofthehigh-lamp).Theinstrumentshouldbebuttoned-upandinastronomymode.Theexposuretimeshouldbesuchthatthesignalfromthedomelamppeaksat45-50kcounts.Domeflatscanbecollectedintwoways:CWI> exptime exposure_time CWI> nexpose numberwheretheexposure_timeisinsecondsandthenumberofdomeflatstobetakenOr:CWI> domeflat numberwheretheexposuretimeissetautomatically,providedthesettingwasconfiguredusingthenew(Sep2014)cwiSetcommand.

2.2.2.3.5. Shortcalibrationsequences(foreachinstrumentsetting,duringthenight,asneeded)

Thereisflexureinthesystemanditisimportanttotakeatleastonecalibrationsetwiththedataduringthenight.Howoftentheseareneededforasinglesettingdependsonthedatabeingacquired.Longexposures,whereskylinesarewelldefined,aremoreeasilycorrectableforflexureeffects.Brighterobjects,wheretheskylinesaregenerallyveryfaint,couldpossiblybenefitfrommorefrequentcalibrationsets.Theshortcalibrationconsistofonearcflatandonecontbars.Thesequencetakesabout6minutesandisinvokedvia:

CWI> Calib wheretheexposuretimeissetautomatically,providedthesettingwasconfiguredusingthenew(Sep2014)cwiSetcommand.


of 47

2.2.2.3.6. SpectrophotometricstandardsTheobservershouldtakespectrophotometricstandardsaswithanyotherspectroscopicobservation.Themoresignal,thebetter,obviously.ItisprobablybettertoditherasliceortwobetweenexposurestohavethestarsampledifferentpartsoftheIFU.

2.2.2.3.7. Detectordarks(Optionaleachafternoon)DetectordarksaregenerallynotusedinN+S,butmightbeneededforstandardobservationswheretheskyisscaled.Usualtechniquesapply.

GuiderCalibration

ThisisataskperformedbytheNightAssistant.AsCWIisnotfittedwithapermanentguider,theconfigurationchangesslightlyeverytimetheguiderisinstalled.OnthePalomarautoguiderscreensettrialmoverateto3seconds.Settrialmovedistanceat45arcseconds(fieldis2x3arcminutes).

GuidermustbecalibratedeverytimetheCassringangleischanged.

2.2.2.4. CenteringTelescopeonCWIIFUandGuider-IFUOffset.ThisisataskperformedbytheobserverwiththeNightAssistant(NA).Thisprocedureshouldbeperformedatthestartofeachnightonanoverheadstarandneartargetsthatarefarfromzenith.Itservesadualpurpose,firstofallitconfiguresthetelescopepointingsuchthatthetargetisatthecenteroftheIFU,secondlyitrefinestheoffsetbetweenthecenteroftheCWIIFUandtheGuider.

1. AsktheNAtoselecta7to9thmagnitudeSAOstarnearthetargetandbeginthemove.2. Oncethemoveiscomplete,asktheNAtotransferthestartotheguider.TheNAmay

havetheneededoffset,althoughfornon-standardCassringangleswewillneedtoprovideit.ThisisdonebyrunningtheIDLprocedureCWI_GUIDER_OFFSETinabeachIDLterminal(seeSection8.4)

3. WhiletheNAismovingthestartotheguider,issue,intheporgyTCLwindow:CWI> startguider (ifnecessary)CWI> centerBoxCWI> contbars <exptime>where<exptime>istheexposuretimeforcontinuumflat.Makeanoteoftheimagenumber(wewillcallitBARNOhere)

4. AsktheNAtosteerthestarintothebox(ifnecessary)andturnonguidinginGUIDEmode(NOTDRIFT).

5. Oncethestarisatthecenterofthebox,asktheNAto:a. turnofftheguidingb. “Z”theoffsetsc. sendreverseoffsets(tostep2)toputthestarontheIFU.

Notethatwedonotwanttosimplyissue“return”.


of 47

6. Whenthereversemotioniscomplete,takeashortexposureonthestar:CWI>exptime<exptime>CWI>exposeWheretheexposuretimeistypically3-10seconds,dependingonthemagnitudeofthestar.Makeanoteoftheexposure(wewillcallitSTARNOAhere)

7. Inspecttheimageafterread-out.IfthestarisnotvisibleontheIFU,wehaveaproblem:

a. firstmakesuretheoffsetissueswereinthecorrectdirectionb. iftheywere,asktheoperatortorepointtoanothernearbystarandrepeatc. ifthatfails,callforhelp

8. IfthestarisontheIFU(mostofthetime!),runinthebeachterminalIDLwindow:IDL> cwi_center_star, /remote, barno=BARNO, starno=STARNOA(seeSection8.2)ThiswillproducegraphicalandtextoutputtellingyouhowmuchthetelescopeneedstobenudgedtocenterthestarattheIFU,aswellasacoarsemeasurementofthestellarFWHM.AsktheNAtomakethenudge.Takeanotherstellarexposure,makenoteoftheimagenumber,STARNOB.RerunIDL>cwi_center_starwiththisnumbertoconfirmthecorrection.Repeatifnecessary.

9. Iftheoffsetisacceptable(generally<1”isgood),then:a. Makeanoteofthe-dRAand-dDecneededtomovefromtheguidertotheIFU,

asdisplayedontheTCSmonitor.NotethatitisthenegativesthatareneededtomoveanobjectfromtheIFUtotheGuider,anditisthenegativesarewhatwewanttorecord.AsktheNAtorecordthesealso.

b. AsktheNAto“TX”thetelescope(unlessthisisthefirstprocedureofthissortbeingperformedduringtherun,inwhichcaseaskthemto“X”).

2.2.2.5. FocusingtheTelescopeThistaskisperformedbytheobserverwiththeNightAssistant.ThetelescopemustbefocusedsothattheimagesitcreatesattheCWIslicerareasclosetoseeing-limitedasisachievable/necessary.TheXybionguider,ifithasbeeninstalledfollowingtheinstructionsabove,isclosetobeingaproxyforthetelescope-slicerfocus.Inlate2013and2014itseemsthattheinstrumentisbetterfocusedwhenthesecondaryismoved-0.5mmfromthebestguiderfocus.

Typically,goodCWIfocusisastellarFWHMontheorderof3-5unbinned(2-3binned)CCDpixels.Ifstarsimagedwiththespectrographappearblurrier,afocussequencewillneedtobeperformed.Thisisdonebytakingimagesfrom-0.1mmto+1mmofthebestguiderfocuslocationin0.25mmincrements,andlookingatlookingattheresultantimagesinsequenceusingds9,oranotherimageviewer.Alternatively,theimagescouldbeinspectedviacwi_center_startogetaquantitativeideaofthefocuscurve.Theoffsetbetweentheguiderandinstrumentbestfocusshouldberecordedandusedthroughouttherun.

2.2.3. NIGHT-TIMEOBSERVATION


of 47

2.2.3.1. LogsTheobserverisresponsibleforthenightlylogs.ThesearediscussedinSection2.2.1

2.2.3.2. ScienceTargetAcquisitionafterSlewingThereappearstobeflexureorpointingerrorwithintheHale—CWIsystemontheorderofafewtensofarc-seconds.ThisiscommensuratewiththeCWIfieldofview,butsmallerthantheguiderfield-of-view.Consequently,itisoftennecessarytorecalibratethepointingeachtimeanewtargetisslewedto.Thisprocedureassumesthattheguider—CWIIFUoffsethasbeendetermined(SectionError!Referencesourcenotfound.).Thisprocedureshouldtakenomorethan5minutes

1. Slewtoa7thto9thmagnitudeSAOstarnearthedesiredsciencetarget2. Takeacontbarsexposure.Continuewiththisprocedurewhilethatisexposing/reading

out3. OffsetthestartotheguiderfieldofviewbyorderingagRagDecoffsetdeterminedin

Section2.2.2.4.4. CentertheguideboxontheguiderscreenbyissuingtheTCLcommand:

“CWI>centerBox”GUIDINGshouldbeOFF.

5. Movethetelescopeuntilthestariswithintheboxeitherviapaddleormanualcommands

6. Settheguidermodeto“GUIDE”(notDRIFT)7. TurnGUIDINGON.8. Oncethestariscenteredwithinthebox,turnoffguiding.9. Orderanoppositeoffsettotheoneorderedbefore:-gRA–gDec.10. Takea2-5secondexposuretoverifythestarisnowcenteredwithintheIFU.Ifitis,TX

thetelescope(thisstepisoptional,thoughrecommendedifthemoveontheskywasverylarge[QUANTIFY!]).Usecwi_center_star

11. IfthestarisnotcenteredattheIFU,adjustthepositionsothatitis.Youmayneedtotakeadditionaldiagnosticexposures.TXonceitis.

12. Commandtelescopemovetothedesiredsciencetarget.Havethetelescopeoperatorselectastarfromtheguiderfieldofviewtoguideon.TheguidershouldbesettoDRIFTmodeandGUIDINGENABLED.Thiswillmovetheguidingboxontothestar,withoutmovingthetelescopeboresight.Theinstrumentisnowreadytotakescienceexposures.

2.2.3.3. ScienceTargetAcquisitionafterLongornearbyExposureCWImaybeusedtotileobjectslargerthanthefieldofviewortolookforsignalinnearbyfieldsthatrequirelongexposuretimes.Ineithercase,flexureorpointingerrormayaccumulate.ItisrecommendedthatthetelescopebeTX-edafterlongexposuresthatusedtheguiderbeforetheguidingisturnedoff.Notdoingsomayintroduceafewarcsecondsofoffsetbetweendesiredandcommandedpositionstonearbyslews.


of 47

2.2.4. STANDARDOBSERVATIONSStandardobservationsareperformedinthesamewayasanyotherinstrument

1. (Optional)SlewtoSAOstarneartarget.Confirmpointing.2. Slewtotarget,acquiretarget3. SelectguidestarandhavetheTODRIFTtheguideboxontothestar,thenGUIDE4. SetexposuretimeattheCWITCLprompt(CWI>exptimeT),whereTistheexposure

timeinseconds5. StarttheexposureattheCWITCLprompt(CWI>expose)6. Aftertheexposure,providedtheinstrumentwasguidingandespeciallyifitwasalong

image,asktheoperatortoTXthetelescope


of 47

2.2.5. NOD-AND-SHUFFLEOBSERVATIONSAsofJanuary2015thereisanewmethodforsettingupnod-and-shuffleobservations.Wefirstdescribethenew(streamlined)methodandthentheold(manual)method.

Nod-and-shuffleobservationsrequirealittlemorepreparationthanastandardobservation.ThefirstimagetheN+Sscripttakesisabiasexposuretoclearthearray.

2.2.5.1. StreamlinedmethodThestreamlinedmethodinvolvesrunningasetupscriptthatasksforuser’sinputandforinteractionwiththetelescopeoperator.YoushouldhavetheoffsetvectorfromthesourcefieldtothebackgroundfieldinarcsecondsNorthandarcsecondsEastavailable.

2.2.5.1.1. StreamlinedmethodsetupThestepsforthesetupareoutlinedbelow.

1. Askthetelescopeoperatortocommandthetelescopetothetargetfield2. Onporgy,commandCWI> nssetup ns_identifier

whereidentifieristheidentifier(essentiallyfilename,soavoidfunnycharacters)thatisuniquetotheobservation

3. Followthepromptsonthescreen.Thescriptwilltellyouwhenitisdone.

Ifyoumakeamistake,youcanfindthescriptonporgyin:~/oldporgy/palomar_guider/ns/ns_identifier.nsYoucaneitheredititwithyourfavoriteeditor(vi/vim/emacs)ifyouknowwhatyouaredoingordeleteitandstartoverwithnssetup.

Experiencedusersmaycopyanexistingscripttoanewfilenameandeditsomeoftheparameterstogenerateaderivedscriptthataddsdithersorshifts,etc.

2.2.5.1.2. StreamlinedmethodinvocationThestepstoinvokethestreamlinedmethodarediscussedbelow

1. Makesurethetelescopeispointedatthetargetfieldanditisguiding2. Onporgy,commandCWI> nsrun ns_identifier3. Payattentiontotheguidermovesforthefirst2stepstomakesuretherearenodelay

issues.Ifthereare,thescriptmayneedtobestoppedandthewaittime(twait)parametermayneedtobeadjustedinthescript.(ifyoudobreakoutofthescript,seedescriptionofns_recoverinSection2.2.5.3onpage25)

2.2.5.1.3. StreamlinedmethoddiscussionThedataenteredbytheuserandcollectedbythenssetupcommandissavedtoans_identifier.nsfile.Thefileisbasicallyapieceoftclsourcecodethatissourcedbyascriptcalledns_wrapper.tclwhennsruniscalled.Anexample*.nsfileisshownbelowwithadditionalexplanationsinblueonyellowbackground.


of 47

Listingofns_ngcXXX.ns# Nod-and-shuffle script parameter file # Generated by NSSETUP # Sunday, 18 January 2015, 12:56:09 PST # Guider rose: GUIDGEOM 0.267857 0.321429 -1 1.53535 0.999372 0.0354387 # P200 focus: 14.88 # Cass angle: -179.97 # Total source exposure time: 1200 seconds # Total bakgnd exposure time: 1200 seconds # 10 iterations. # Wall clock duration will be ~48 minutes. # Number of subexposures per field set n 10 # Exposure times on source and background in ms. set expts 120000 set exptb 120000 # Source field guider information (sameasoutput of CWI> getTarget) set p1x 329 set p1y 124 set p1s 30 set p1m 5 set intens1 0 set ccd x4 set grabmode1 frame set grabexp1 1 set grabstack1 11 # Vector from source to background (Notethattheseneedtobeintegers) set mvN1 110 (movesunder300arcsecondsineachaxisarepreferred) set mvE1 -54 # Background field guider information (sameasoutputof CWI> getBackground) set p2x 329 set p2y 124 set p2s 30 set p2m 5 set intens2 0 set grabmode2 frame set grabexp2 1 set grabstack2 11 # Delay times (inmilliseconds) # Change twait for long throws set twait 8000 (Increasethisifyoursubexposuresstartbeforemovescomplete) set gwait 3000 # NS Version: set nsversion ns_ngcXXXX


of 47

2.2.5.2. ManualMethod–EXPERTUSEONLYThemanualmethodinvolvesmoreinteractionswiththetelescopeoperatorandcutting-and-pastingcommandoutputsintoanod-and-shufflescript.

2.2.5.2.1. QuickVersion1. CopytemplatescripttonewfilenameforuseforthisN&S2. Turnguidingoff3. Gototarget4. Driftontoguidestar,enable,thenguide5. getTarget6. pastepositiondataintoscript7. stopguiding(guidersetguiding0)8. movetobgfield(e.g.,guidersetmove86-13630)9. drift,enable,guide10. getBackground11. pastepositiondataintoscript12. stopguiding(guidersetguiding0)13. movebacktofgfield(e.g.,guidersetmove-8613630)14. makesurethecorrecttargettobackgroundoffsetisinthescript15. startscript

2.2.5.2.2. LongVersion1. Makesureyouhavethefollowinginformationfromtheobserver:

a. Targetcoordinatesb. Backgroundcoordinatesc. Offsetfromtargettobackgroundinarcseconds(dNorth,dEast)

(yes,youcouldcomputeitfromthevaluesinaandb,inprinciple)

2. Inthe~/oldporgy/palomar_guiderdirectorycopyns_template_150118.tcltopickaname.tcl.Alternatively,youcouldcopyscirptjustused.tcltopickaname.tcl.Youwillneedtoeditthescripttoadjustguidinginformationandtuneexposuretimes.Thestartofascriptisreproducedbelowwiththepartsthatyoumayneedtoadjusthighlightedandexplanationsinred.# NOD AND SHUFFLE SCRIPT # TAKES 1/2 EXPOSURE OF SKY, LOOPS THROUGH TARGET # AND SKY AND ENDS WITH 1/2 EXPOSURE OF SKY # version of this NS script set nsversion [info script] # tracker flag, decides whether we try to access the palomar guider or not. set tracker 1 if {$tracker} {


of 47

puts "load guider package" load /usr/lib/libautoguider.so puts "connect to guider" guider host 198.202.125.194 }; #$tracker #total number of cycles set n 10 ßNumberofon-targetexposures # total number of subexposures: set nsteps [expr {2*$n+1}] #exposure time at source (ms)

set expts 120000 ßExposuretimeonsourcepercycle(inms) #exposure time at background (ms)

set exptb 120000 ßExposuretimeonbackgroundpercycle(inms) #exposure time for half-fields set exptb2 [expr {$exptb/2}] # write the exposure time to file set nsfile [open "ns.exptime" w] puts $nsfile $expts close $nsfile

### GUIDER SETTING BEGIN --------------------------- #time to wait (ms) set twait 8000 ;# settling time after a move set gwait 5000 ;# waiting time after a "stop guiding" command is issued #guider gain setting set ccd x4 ; # CCD gain #source guide star coordinates and intensity data # the 'getTarget' command in the stage.tcl program # will return all these values # # Go to science field # Drift guider box onto guide star # run getTarget: prints out required settings for target field # # next, move to background field # Drift guider box onto guide star # run getBackground: prints out required settings for background field # # source field will move 4 steps, then back # background field will move up to F # # script always starts and ends on source position (even though first and # last exposures are on background) # # getTarget # x,y are guider coordinates for science field # s is size of box # m is box margin size (delta from inside box to outside box)


of 47

set p1x 436 ßTheseentriesarecut-and-pastedfromtheoutputofgetTargetset p1y 151 set p1s 27 set p1m 5 set intens1 95 set ccd x4 set grabmode1 frame set grabexp1 2 set grabstack1 8

# the 'getBackground' command in the stage.tcl program # will return all these values

set p2x 461 ßTheseentriesarecut-and-pastedfromtheoutputofgetBackground set p2y 360 set p2s 27 set p2m 5 set intens2 93 set grabmode2 frame set grabexp2 2 set grabstack2 8 #source to background move

set mvN1 -107 ßThesevaluestobesuppliedbytheobserver(dNorth,dEast) set mvE1 -110

3. [Optional,butstronglyrecommended]SlewtoanSAOstarnearthemaintargettoconfirmpointing

4. Askthetelescopeoperatortoslewtotargeta. Askthetelescopeoperatortoadjusttheguidersettingstotheirsatisfactionand

toDRIFTtheguideboxontoanacceptablestar.ThenswitchtoGUIDEmode.Notethatstarsnearthecenteroftheguiderfieldarepreferredifyouintendtodomacroscopicdithers.

b. Issue“CWI> getTarget”Thisprintsouttheguiderinformationforthetargetfieldthatwillneedtobecut-and-pastedintothenod-and-shufflescript.Example:CWI> getTarget set p1x 548 set p1y 165 set p1s 24 set p1m 4 set intens1 0 set ccd x4 set grabmode1 frame set grabexp1 3 set grabstack1 17

c. Stopguiding“CWI>guidersetguiding0”

5. Askthetelescopeoperatortoslewtothebackgroundfield


of 47

a. AskthetelescopeoperatortoadjusttheguidersettingstotheirsatisfactionandtoDRIFTtheguideboxontoanacceptablestar.ThenswitchtoGUIDEmode

b. Issue“CWI>getBackground”Thisprintsouttheguiderinformationforthetargetfieldthatwillneedtobecut-and-pastedintothenod-and-shufflescript.

c. Stopguiding“CWI>guidersetguiding0”

6. Verifythattheoffsetmoveiscorrect.a. Whilestillonthebackgroundfieldissue:

“CWI>guidersetmove–dNorth–dEast30”Thiswillreturnthetelescopepointingtothesourcefield.

b. Oncethemoveiscompleted,movetheguiderboxvia“CWI>guidersettarget1valp1xvalp1ypalp1svalp1m”wherevalp1?arethenumericalvaluesobtainedin4babove.

7. Youshouldnowbeguidingontarget.SavetheN+Sscriptandexecuteit:a. “CWI>sourcepickaname.tcl”b. Sitbackandtakeanap.Youmaywanttomakesurethattherewasn’tanextra

0intheexposuretimelengthandyoudidn’tjustaskforaday-longexposure

2.2.5.3. AbortinganexposureandresettingthesystemAbortinganod-and-shuffleexposurecanbeproblematic.Butitmustbedonesometimes(clouds,fog,wrongparametersortarget).

1. BreaktheNod-and-ShufflescriptviaCTRL+C.Thisisbestdoneduringatelescopemoveduringtheexecution

2. RestarttheCWItclshwith‘sudo –E tclsh’attheporgyshellprompt3. “CWI >sourcens_recover.tcl”

Notethatthisproceduremayneedtowaitafewminutesforapreviouslycommandedsub-exposuretofinish.


of 47

3. ENDOFNIGHT(THINGSTODOATTHEENDOFEACHNIGHT)

3.1. PARKTELESCOPEAskthetelescopeoperatortoparkthetelescope,closethedomeshutters,andthemirrorcover.

3.2. COPYMISCELLANEOUSFILESCopythelogfile(inxlsx,txt,andcsvformats)tothenightlydatadirectoryonporgy

Copyandscriptsusedtothenightlydatadirectoryonporgy

3.3. TRANSFERDATATOBEACHTransferfilesfromporgytobeachbyissuing“porgy2beach”frombeachcommandprompt.Asof150414thismaybeautomated.Askyoursupportperson.

3.4. TRANSFERDATATOSRL.CALTECHANDGUESTOBSERVER’SREPOSITORY,IFAPPLICABLE

3.5. PLUGINTHEGRATINGROTATORENCODERIFITWASUNPLUGGEDReattachthegratingencoderifitwasdetachedforobservations.

3.6. PARKALLMOTORS(IMPORTANT!)Parkstagesbyissuingthe“CWI>park”commandfromtheCWITCLshellonporgy.Telescopemustbeparkedforthis.

3.7. CHECK/TURNOFFCALIBRATIONLAMPS

4. ENDOFINSTRUMENTRUN(THINGSTODOATTHEENDOFTHELASTNIGHT)

4.1. GOTHROUGH“ENDOFNIGHT”ACTIONS

4.2. TRANSFERSCRIPTDIRECTORYTarballthepalomar_guiderdirectoryonporgy.Nameitpalomar_guider_YYMMDD.tar.gz

Transferthetarballtobeachandtothecampusrepository

4.3. POWERDOWNTHEINSTRUMENT(OBSERVATORYSTAFF)• “dheclose”topowerdowntheCCD

o Issue“dheclose”atcommandpromptonporgytoswitchoffpowertothedetector.• Powerdownshuttercontrol


of 47

• ClosetheGUI• PowerdowngrayCCDpowersupply• PowerdownLakeshoreunit• Powerdowncalibrationunitpowersupplies• Turnoffmotorpowersupplies• Powerdownporgy

o Issue“sudoshutdown–hnow”atporgycommandprompt• Unplugbenchfromrack• UnplugrackfromCassegraincage• Turnofftheoffsetguider• Powerdownbeachandstow• Coilcablesinsideenclosure• Buttonupenclosure• Installdustcoversontopofinstrument


of 47

5. APPENDIXI–OBSERVER’SREFERENCE

5.1. GENERALCOMMENTSTheobserverisresponsiblefordesignatingthegrating,filter,andnod-and-shufflemaskconfigurationforeachnightsufficientlyearlyfortheinstrumentstafftoimplementanynecessarychanges.Multipleinstrumentconfigurationsforasinglenightrequirethepresenceofqualifiedpersonnelduringtheobservingnightandwillonlybeconsideredunderspecialcircumstancesuponrequest.

Thelistsbelowdonotexplaintheindividualtasks.Thatisaddressedinothersectionsandreferencedhere.

5.2. AFTERNOON

5.2.1. BEFOREDOMEISDARK1) Confirmwithobservatorystaffthatthedesiredgrating,filter,andnod-and-shufflemask

positionareconfiguredforyourdesiredwavelengths.2) Startadailylog.Thisismostlyforyou,butrelevantinstrumentcommentsarevitalin

casesomethinggoeswrongand/ortohelpwithdatareduction.3) Confirmwiththestaffthattheinstrumentfocus(FM2),andlateralposition(FM4)stages

havebeenconfiguredfortheinstalledgrating4) Makesurethedatadirectoryissetcorrectlyandtakeatestbiasimage5) [MAKESURETHECAMERAISFREETOMOVE—ASK]Foreachsetting:

a. Confirmwavelengthrangeforeachsettingb. Establishexposuretimesforcalibrationanddomeflatimages

5.2.2. AFTERDOMEISDARK1) Complete“Afternoon”tasks2) Takeasetof10biases[20minutes]3) [MAKESURETHECAMERAISFREETOMOVE]Foreachsetting:

a. Takeafullinternalcalibrationset[~30minutes]b. Take3to5domeflats[7to10minutes]

5.3. EVENINGTWILIGHT1) Complete“AfterDomeisDark”items2) Sendcamerato0positionandaskPalomarstafftotopoffthedewarand

WAITFORFILLTOBECOMPLETEDANDDEWARDISCONNECTEDNote:Somenon-zeropositionsareOKforfill(notably,anypositivearticulationstagepositions,forinstance).

3) Openthedomewhenready4) Putcamera/gratinginfirstrequiredsettingafterfilliscompleteanddewar

disconnected


of 47

5) RotatetheinstrumenttothedesiredCassringangle6) CalibratetheguideriftheCassangleisdifferentthanpreviousobservation7) Starttrackingandfocustheguider8) Establish/Confirmtheguider—IFUoffsetforZenith9) Focustheinstrument10) Gotofirsttarget

a. refineguider—IFUoffset,ifneededb. refocus,ifneededc. setupN+Sscript,asneeded

11) Taketwilightflats/standardstars/etc.,asdesired

5.4. NIGHT1) Completethemajor“Twilight”tasks,ifnecessary(hopefully,you’redone)2) Lineupontarget3) Observe4) Takeatleastonecalibrationsetforeachsettingduringthenight(7minutes)5) Periodicallytransferdatatobeach(automaticsince150414)6) PeriodicallyissueagetTempscommand(fewseconds)

5.5. MORNINGTWILIGHT1) PerformanyobservationsthatareOKintwilight2) Completeanyrelevant“EveningTwilight”tasks3) Completeanyrelevant“Afternoon”tasks4) Startany“Morning”tasks

5.6. MORNING1) Parktelescope2) Completeanyrelevantandoutstanding“MorningTwilight”tasks3) Parkinstrumentstages(plugingratingencoder,ifunplugged;telescopemustbe

parked)4) Turnoffalllamps5) Copyyourlogfiletotheporgydatadirectory6) Copyanyobservingscriptsusedtotheporgydatadirectory7) Takeastackof10biases(especiallyifyoudidn’tintheaft/eve)(20minutes)8) Transferdatatobeachandtarball9) Transferdatatocampusandyourrepositories


of 47

6. APPENDIXII–COMMANDGLOSSARYThisisanabbreviatedcommandsummary,functionallyordered.“CWI>”issimplytheCWItclshprompt.

6.1. CONFIGURATIONCOMMANDSCWI>cwiSetconfiguration_name

AddedSeptember14,2014.Intendedasareplacementfortheart_XXXXcommands. Thiscommandloadsacwisettingthathasbeenpreviouslydetermined.Thesettingsarestoredinthe./settings/subdirectoryofthepalomar_guiderdirectory.Settinginformationincludestheexpectedgrating,centralwavelength,cameraarticulationsetting,gratingstagesetting,exposuretimeforarclampandcontinuumlampcalibrationsanddomeflatexposuretime.Theconfiguration_nameistypicallyoftheformB_4861orR_halpha,wherethefirstcharacterimpliesthegratingandtheremainderidentifiesthesetting.

CWI>ConfigureDetector[ONCEPERRUN]

SendtheSRS,SOS,andreadmodecommandstosetupthedetectorforslowlower-leftampreadout

CWI> YellowSettings

MoveFM2forthebluegratingfocuspositionandadjustFM4tocenterthespectra

CWI> RichSettings


CWI> BlueSettings


CWI>art_hbeta[DEPRECATED]

SettheCWIgratingandcamerapositionstoplaceH-betanearthecenteroftheCCD,assumingtheBLUEgratingandfilterarein.

CWI>RedSettings

MoveFM2fortheredgratingfocuspositionandadjustFM4tocenterthespectra

CWI>art_halpha[DEPRECATED]

SettheCWIgratingandcamerapositionstoplaceH-alphanearthecenteroftheCCD,assumingtheREDgratingandfilterarein.


of 47

CWI>art_has2[DEPRECATED]

SettheCWIgratingandcamerapositionstohaveH-alphaandSII(6716)withinthenod-and-shufflemask,assumingtheREDgratingandfilterarein.YouonlygettheshorterofthetwoSIIlinesandtheconfigisalittleiffy.

CWI>rp

Printoutthestagepositions(motorcounts).Order:FM1,FM2,FM3,FM4,Grating,Camera,CalX,CalY

CWI>tp

Printoutstagepositions(encodercounts)Orderthesameas“rp”above

CWI> st

Stopsstagemotion

CWI>grating_paN

Setthegratingpositiontothespecifiedvalue

CWI>camera_paN

Setthecameraarticulationstagepositiontothespecifiedvalue

CWI>lockGrating

Createsalockfilethatpreventsgratingmovecommandsfrombeingexecuted

CWI>unlockGrating

Removesthelockfilethatpreventsgratingmovecommandsfrombeingexecuted

CWI>TelFocusmm.m

Changethetelescopefocustopositionmm.m(secondarysetting).Willnotperformthemoveifmm.m<10.0or>20.0.ThisisaCWIcodelimitation,notaPalomarconstraint.

CWI> park

Parkallmechanisms.NOTE:Telescopemustbeparkedbeforeissuingthiscommand.


of 47

6.2. MODECOMMANDS

CWI>fm1_astro[ENGINEERING]

Movetheperiscopeintoastronomyposition

CWI>fm1_calib[ENGINEERING]

Movetheperiscopeintocalibrationposition

CWI>sel_flat[ENGINEERING]

Selectstheflatcalibrationobject

CWI>sel_dark[ENGINEERING]

Selectsthedarkcalibrationobject(acover,ofsorts)

CWI>sel_horizontal[ENGINEERING]

Selectstheverticalbars(despitethename–historical)

6.3. CALIBRATIONCOMMANDS

CWI>CalibRed[DEPRECATED]

Takesthefollowingcalibrationsequence: 20secondarcflat 10secondcontinuumbars 10secondcontinuumflat

Returnstheinstrumenttoastronomymode,turnsofflamps,selects“dark”target

CWI>CalibBlue[DEPRECATED]

Takesthefollowingcalibrationsequence: 20secondarcflat 30secondarcbars 60secondcontinuumbars 40secondcontinuumflat



of 47

CWI>CalibBlueDim[DEPRECATED]

Takesthefollowingcalibrationsequence: 60secondarcflat 60secondarcbars 90secondcontinuumbars 60secondcontinuumflat


CWI>contbarsT

TakesacontinuumbarsexposureofspecifiedexposurelengthT.Tdefaultsto25secondsifnotspecified.Returnsallstagestoastromode.Writesout*.infofile.

CWI>arcflatT

TakesanarcflatexposureofspecifiedexposurelengthT.Tdefaultsto15secondsifnotspecified.Returnsallstagestoastromode.Writesout*.infofile.

CWI> contflatT

Takesacontinuumflat.Returnsallstagestoastromode.Writesout*.infofile

CWI>calibrateabcdefgh [DEPRECATED]

Shouldnotneedtoinvokethiscommand.Takesthefollowingexposures: arcflat:aexposuresofexposuretimeb arcbars:cexposuresofexposuretimed contbars:eexposuresofexposuretimef contflat:gexposuresofexposuretimeh Exposuretimesareinseconds,numberofexposuresmustbe1orgreater.Returnstheinstrumenttoastromodeafter.Writesout*.infofile.

CWI>calibshortabcdef [DEPRECATED]

Shouldnotneedtoinvokethiscommand.Takesthefollowingexposures: arcflat:aexposuresofexposuretimeb contbars:cexposuresofexposuretimed contflat:eexposuresofexposuretimef Exposuretimesareinseconds,numberofexposuresmustbe1orgreater.Returnstheinstrumenttoastromodeafter.Writesout*.infofile

CWI>domeflatN

TakesNdomeflatexposures.Thehighlampneedstobeonandthemirrorcovermustbeopen.TheexposuretimedefaultstothatloadedwhencwiSetisinvoked.


of 47

CWI> arc_on[ENGINEERING]

CommandsthearclamponCWI> arc_off[ENGINEERING]

CommandsthearclampoffCWI> cont_on[ENGINEERING]

CommandsthecontinuumlamponCWI> cont_off[ENGINEERING]

CommandsthecontinuumlampoffCWI> all_off Commandsalllampsoff.

6.4. EXPOSURECOMMANDSCWI>exptimeT

SettheCWIexposuretimeinSECONDS.Tdefaultsto1second.

CWI>expose

StartaCWIexposure.Writesouta*.infofilealongwiththeimage.

CWI>nexposeN

TakesNCWIexposures.Writesouta*.infofileforeachimage.

CWI>biasN

TakesNbiasexposures.Ndefaultsto1.

CWI>ndarkN

TakesNdarkexposures.Ndefaultsto1.Setexposuretimewithexptimefirst

CWI>domeflatN

TakesNdomeflatexposures.Thehighlampneedstobeonandthemirrorcovermustbeopen.TheexposuretimedefaultstothatloadedwhencwiSetisinvoked.


of 47

6.5. GUIDERCOMMANDS

CWI>startguider

InitializestheconnectiontotheShepherdPalomarautoguider.Thereisseparatedocumentationforthiscode.

CWI>centerBox

Centersthetrackingboxontheguiderfieldofview

CWI>getRose

Printstheguiderplatescaleandorientationinformation.Wrapperfor“guidergetgeomabcdef”

CWI>getTarget

Printstheinformationforthetargetcurrentlybeingguidedon.Printsthedataoutinaformattobeusedinnod-and-shufflescriptsforthetargetfield(wrapperforguidergettargetabcde)

CWI>getBackground

Printstheinformationfortheobjectcurrentlybeingguidedon.Printsthedataoutinaformattobeusedinnod-and-shufflescriptsforthebackgroundfield

CWI>guidersetmoveNorthEastRate

Movesthetelescopethespecifiedamount(inarcseconds)atthespecifiedrate(inarcseconds/second.Rateshouldbe<35.Thereareproblemsifitisabove35.

CWI>guidersettarget1XYSM

Movestheguiderboxtoguiderpixel(X,Y).BoxisofsizeSwithmarginM.Notethe‘1’asthefirstparameter,thisismandatory.

CWI>guidersetguiding1/0

Turntheguidingonoroff.Alwaysbecarefulastowhethertheguiderissetto“GUIDE”or“DRIFT”mode


of 47

6.6. INFORMATIONALCOMMANDS

CWI> getTempsN

PrintsthelastNCCDtemperaturereadingstothescreen.Ndefaultsto3.

CWI>reqpos

Getsomeinformationfromthetelescopeandprintittothescreen

CWI>reqstat

Getsomeotherinformationfromthetelescopeandprintittothescreen


of 47

6.7. DRAGSTAR.TCL[NOTTESTEDRECENTLY]

Thisisatclprocedurethatstartswithastaratthecenterofthesliceritthenscansthestaracrosstheslicer(overall24slicermirrors).Theprogramisnotverysophisticated–thecurrentexposuretimeis~2.5secondsperslice.

CWI>sourcedragstar.tcl


of 47

6.8. APPENDIXIII–ALPHABETIZEDCOMMANDLISTObserveraccessiblecommandsareinGREEN

CWI> all_off

CWI> arc_on[ENGINEERING]

CWI> arc_off[ENGINEERING]

CWI>arcflatT

CWI>biasN

CWI> BlueSettings [ENGINEERING]

CWI> Calib

CWI>CalibBlue[DEPRECATED]

CWI>CalibBlueDim[DEPRECATED]

CWI>calibrateabcdefgh[DEPRECATED]

CWI>CalibRed[DEPRECATED]

CWI>calibshortabcdef[DEPRECATED]

CWI>camera_paN[ENGINEERING]

CWI>centerBox

CWI>ConfigureDetector[ENGINEERING]

CWI>contbarsT

CWI>contflatT

CWI> cont_on[ENGINEERING]

CWI> cont_off[ENGINEERING]

CWI>dayCalib

CWI>dayCalibShort

CWI>domeflats

CWI>expose

CWI>exptimeT

CWI>fm1_astro[ENGINEERING]

CWI>fm1_calib[ENGINEERING]


of 47

CWI>getBackground

CWI>getRose

CWI>getTarget

CWI> getTempsN

CWI>grating_paN[ENGINEERING]

CWI>guidersetguiding1/0

CWI>guidersetmoveNorthEastRate

CWI>guidersettarget1XYSM

CWI>lockGrating[ENGINEERING]

CWI>ndarkN

CWI>nexposeN

CWI> park NOTE:Telescopemustbeparkedbeforeissuingthiscommand.

CWI>RedSettings[ENGINEERING]

CWI>reqpos

CWI>reqstat

CWI> RichSettings[ENGINEERING]

CWI>rp

CWI>sel_dark[ENGINEERING]

CWI>sel_flat[ENGINEERING]

CWI>sel_horizontal[ENGINEERING]

CWI> st

CWI>startguider

CWI>TelFocusmm.m[ENGINEERING]

CWI>tp

CWI>unlockGrating[ENGINEERING]

CWI>YellowSettings[ENGINEERING]


of 47

7. DETERMININGCONFIGURATIONSANDMAKINGCONFIGFILESThisisintendedasaquick-lookreferenceforgeneratingconfigurationfiles

1. MakesureyouhavethedesiredcentralwavelengthfromtheobserverinAngstroms2. Makesurethecorrectgratingisinstalled3. onbeach,runIDL> CWI_SETTING, wavelength

(wherewavelengthisinangstroms)Makeanoteoftherequiredcameraandgratingreadingsfortheinstalledgrating

4. onporgyin~/oldporgy/palomar_guider/settings/cp X_Template.cwi G_WVLG.cwiwhere:Gisthegratingcode(B/R/Y/M)andWVLGisthe4digitwavelengthinAngstrom,e.g.:B_5005.cwi(bluegrating,5005A)

5. editG_WVLG.cwiinyourfavoritetexteditor(choose:vi?emacs?),changethecomments,thegratingname(ifnecessary)andsetgrating_posandcamera_postothevaluesfoundin3.Verifythesigns,theyareimportant.Leavethearc(10s),cont(10s),anddome(25s)exposuretimesatthevaluesinthetemplatefilefornow.

6. Makesurethedewarisnotfillingandthecameraisfreetomoveonporgy,runCWI> cwiSet G_WVLGWaitforthecameraandgratingstagestofinishmoving

7. takea10secondarcflat:CWI> arcflat 10 ;Checktheflux,computeanexposuretimethatwouldputthepeakvaluearound50,000counts.EdittheG_WVLG.cwifiletoreflectthisvalue.MakeanoteofthearclampfilenumberARCNO

8. onbeach,RunIDL> cwi_compare_arc, /GRATING, ARCNOwhere/GRATINGisthegrating,i.e.,/BLUE,/RED,etc.Adda/NSswitchifthenod-and-shufflemaskisinstalledInspecttheIDLgraphicswindowtoconfirmthesetting

9. Takea10secondcontinuumflat:CWI> contflat 10;Checktheflux,computeanexposuretimethatwouldputthepeakvaluearound50,000counts.EdittheG_WVLG.cwifiletoreflectthisvalue.

10. runCWI> cwiSet G_WVLGtoloadthenewarcflatandcontflatexposuretimes11. Runashortcalibrationscript:CWI> Calib;Inspectthethreeresultantimagesforflux

level.12. OncethedomeisdarkandCWIrearpanelinstalled,takea25sdomeflat:

CWI> domeflatinspectthedomeflatimageandadjusttheexposuretimetopeakaround50,000counts.EdittheG_WVLG.cwifiletoreflectthisexposuretimevalue.

13. RunCWI> cwiSet G_WVLGagaintoloadinthenewvalues.Youaredone.


of 47

8. APPENDIXIII–AUXILLIARYPROGRAMS ThereareanumberofIDLauxiliaryproceduresthathavebeenwritten.Thissectionisaquick(andincomplete)listoftheprogramsthatmightbeuseful.

8.1. CWI_SETTING.PROPrintstheCWIsettingsneededtocenteraparticularwavelengthontheCWIdetector.NotethatCWIsettingsmightactuallydiffersomewhatfromthevaluesreportedbytheprogramastheyarethenoptimizedforghostposition,etc.Notethatmorethanonegratingmaybeabletoaccessaparticularwavelength–makesureyouusethecorrectgratingvalueswhengeneratingasettingsfile.

Callingsequence:

IDL>CWI_SETTING,Wavelength

Example:

IDL> cwi_setting,6563 % CWI_SETTING: CWI Grating Settings Calculator % CWI_SETTING: **************** % CWI_SETTING: BLUE GRATING % CWI_SETTING: **************** % CWI_SETTING: 6563.0A is outside the BLUE grating range. % CWI_SETTING: **************** % CWI_SETTING: Yellow GRATING % CWI_SETTING: **************** % CWI_SETTING: YELLOW grating setting for 6563.0A: % CWI_SETTING: Articulation/Camera stage RP = -1128221 % CWI_SETTING: Grating stage RP = -16749 % CWI_SETTING: **************** % CWI_SETTING: RED GRATING % CWI_SETTING: **************** % CWI_SETTING: RED grating setting for 6563.0A: % CWI_SETTING: Articulation/Camera stage RP = 186093 % CWI_SETTING: Grating stage RP = 6164


of 47

8.2. CWI_CENTER_STAR.PROOneofthetaskswehavehadalotof“fun”withiscenteringreferencestarsontheCWIIFU.Usuallythisisdonemanuallybyholdingapenciluptothemonitororblinkingtwoimages.Thisprogramisanattempttoautomatetheprocedureandmakeitmorerepeatable.Itrequiresafewthings:

1. IDLwindowopenonobserver22. Acontinuumbarsimagetakenatcurrenttelescopeorientationtoensureflexuredoes

notaffectthealignment.BestwaytoacquirethisistogototheSAOstarthatwillbeusedforpreliminaryalignmentnearthetargetandtoissuethe“CWI> contbars”commandwhichwillacquireacontinuumbarsimage

3. AgoodqualityCWIspectrumofthestarbeingusedforalignment

Callingsequence

IDL>CWI_CENTER_STAR,/REMOTE,BARNO=barno,STARNO=starno

The/REMOTEswitchtellstheprogramtolookforthefilesonporgyratherthanonthelocalmachinebarnoisthenumberofthecontinuumbarsstarnoisthenumberofthestar

Example:

IDL> cwi_center_star,/REMOTE,barno=7644,starno=7642 <somediagnosticnumbersshowuphere>To center the star from image: 7642 on bars from image: 7644 you must offset the telescope: 1.1 arc seconds North 1.0 arc seconds East Discussion:

Theprogramcentersthestarbystraddlingitbetweenthetwocenterslicesandmatchingthecentroidwithintheslice.Itcorrectsforrelativefluxdifferencesbetweenslices.WhiletheprogramworksOK,ithasnotbeenextensivelytestedforrobustness.Ascreencapisgivenbelow.ThecodenowtakesintoaccounttherotationoftheCassring.ItalsoattemptstocomputethestellarFWHM.


of 47


of 47

8.3. CWI_COMPARE_ARC.PROIt’sgenerallyagoodideatomakesurethatthespectrographhasbeenconfiguredtothecorrectwavelengthrange.Theprogramreadsthe.infofileassociatedwiththespecifiedarctodeterminethestagesettings.Itthenplotscutsthroughfourslicesandareferencespectrum.Userneedstospecifywhichgratingisin,andwhetherthenod-and-shufflemaskisinserted

CallingSequence:

IDL>CWI_COMPARE_ARC,arcno,/NS,[/grating_name] /NS:setifN+Smaskisin /RED:iftheredgratingisin /BLUE:ifthebluegratingisin/YELLOW:iftheyellowgratingisin/MEDREZ:ifthemediumresolutiongratingisin arcno:thenumberofthearctoplot

Example:

IDL>cwi_compare_arc,7481,/ns,/red

Thecolorofthereferencespectrumindicateswhichgratingthisisfor.Thedashedlinesshowthecenterrowfortheslicecutsandthenominaltuningwavelengthforthereference.


of 47

8.4. CWI_GUIDER_OFFSETComputestheapproximateguideroffsetfromtheCWIIFUtotheguiderfieldcenter.

Theangleisgivenindegrees.

RememberthattheoffsetisapproximateandwillhavetobecorrectedusinganIFU-centeringprocedure.

% Compiled module: CWI_GUIDER_OFFSET. % CWI_GUIDER_OFFSET: TCS Cass angle in Degrees % CWI_GUIDER_OFFSET: The values are approximate! % CWI_GUIDER_OFFSET: % CWI_GUIDER_OFFSET: IFU --> Guider: 489.6" S, 396.5" W


of 47

8.5. CWIDS9REGIONTEMPLATEFILEAds9regiontemplatefileisavailable.ThetemplateincludesboththeCWIinstrumentandguiderfields-of-view.Figure4isascreencapofads9windowalongwithaconfigurationdialogthatallowstheusertosettheCassringangle(Angle).ThefieldisaDSSimagedownloadedusingds9.Thesmallcircleinthebottom-leftcorneroftheguiderfieldcorrespondstothetop-rightcorneroftheguiderscreen(0,0)coordinate.

Figure5showsazoomedinscreen-shotoftheguiderfieldintheds9windowandaphotographoftheguiderscreen.

ThePalomarAutoguider,intheCWIconfiguration,seemstoguideOKdowntoV~17thinreasonableseeingconditions.

Theregioncwi_fov.tplsourcecodeisreproducedbelowandcanbeobtainedbycontactingMatt([email protected]),oryoucouldjustcut-and-pastefrombelow.Thefileisloadedvia‘Region->Template->Load…’inthetopmenubar.

Figure4.CWIds9templatesuperimposedonatargetfield.IFUFOVislabeled"CWI."GuiderFOVislabeled“Guider.”The“Angle”fieldintheds9dialogwindowcorrespondstotheCassegrainrotatorsetting.


of 47

Figure5.CWIPredictedfieldandcorrespondingguiderphoto

# Region file format: DS9 version 4.1 # Matuszewski 140421 # Guider field position and size are good to about +/-5 arc seconds # The limiting star magnitude for the guider is (at present) unclear. # CWI has guided on Vmag~15 stars and, ought to be able to go down to Vmag~17. # These values will be updated over the next couple of CWI runs. global color=gold dashlist=8 3 width=1 font="helvetica 10 bold roman" select=1 highlite=1 dash=0 fixed=0 edit=1 move=1 delete=1 include=1 source=1 wcs0;fk5 # composite(0,0,180.00) || composite=1 color=gold font="helvetica 12 bold roman" box(0,0,40",60",0) || # color=gold font="helvetica 12 bold roman" text={CWI} # vector(0,0,200.0",-90) || vector=1 color=gold font="helvetica 12 bold roman" dash=1 box(-0.12733239,0.11851218,153",185",0) || # color=gold font="helvetica 12 normal roman" text={Guider}

cwi procedure version 31 4/3/16 7:50:00 pm cosmic web ......• cwi is sensitive enough to pick up...

Documents