Integral)Field)Spectroscopy)of)High6Redshi8)Galaxies)with ... ·...
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Integral Field Spectroscopy of High6Redshi8 Galaxies with the E6ELT spectrograph HARMONI S. Kendrew 1 , S. Zieleniewski 1 , N. ThaIe 1 , J. Devriendt 1 , R. Houghton 1 , T. Fusco 2 , M. Tecza 1 , F. Clarke 1 , K. O’Brien 1 1 University of Oxford, 2 ONERA 7 Paris [email protected] ABSTRACT We present here first results of novel simulated integral field spectroscopic observaHons of a z = 3 galaxy with HARMONI, a first light instrument for the 397m European Extremely Large Telescope. Instead of extrapolaHng exisHng observaHons to higher z, our study is based on output from cosmological simulaHons with the grid7based adapHve mesh refinement code RAMSES. Using the physical properHes of the RAMSES star parHcles in combinaHon with stellar populaHon synthesis models, we produced a 3D spectral cube of the galaxy’s starlight. A HARMONI observaHon of this galaxy was simulated using a dedicated soUware tool. We show here details of the input data and spaHal and spectral light properHes, and simulated observaHons with HARMONI. This work will demonstrate how HARMONI will extend the resolved spectroscopic and kinemaHc study of galaxies to the early Universe, and show how predicHons from advanced cosmological codes will be tested observaHonally at high redshiUs with next7generaHon instruments. HARMONI: INTEGRAL FIELD SPECTROSCOPY WITH THE E6ELT The HARMONI instrument (PI: N. ThaXe; [1]) will provide IFS at visible and near7 IR wavelengths on the E7ELT. Assisted by single conjugate and laser tomographic AO (SCAO; LTAO), HARMONI will achieve unprecedented spaHal resoluHon over a 6.4 x 9.1” field of view. Key science with HARMONI covers many areas in astrophysics, from characterizaHon of extrasolar panets to studies of high7 redshiU galaxies. To esHmate the scienHfic performance of HARMONI and support the instrument design, a simulator was developed that produces realisHc output data cubes [2,3]. A SIMULATED GALAXY AT Z=3 SimulaHons of cosmic structure formaHon allow us to study the origin and evoluHon of galaxies through cosmic history. Such simulaHons today have sufficient spaHal and mass resoluHon to make quanHtaHve observaHonal predicHons, and indeed pose challenges to the ΛCDM paradigm [4]. We use here output from one such simulaHon, using the RAMSES code [5], to produce a spectral cube of a star7forming galaxy at z = 3, which will consHtute a typical observaHonal target for HARMONI. Input Data We extracted a 4 x 10 10 M solar star7forming galaxy from a RAMSES simulaHon run terminated at z = 3, in a 10 x 10 kpc box, corresponding roughly to 3 effecHve radii. The galaxy is described by 2.5 x 10 6 star, gas and dark maXer parHcles; Fig. 1 shows the dark maXer and gas (baryonic) density and Fig. 2 the radial profiles of mass and density, as well as properHes of the stars’ metallicity and formaHon history. Analysis of the RAMSES data was performed using Python package pynbody [6]. Fig. 1 : Dark maXer density plot (L) & detailed gas density plot (R) for the a star7 forming galaxy at z=3, as produced in cosmological simulaHons with the RAMSES AMR code [5]. Stellar popula[ons We employ the stellar populaHon synthesis models of Bruzual & Charlot [BC03; 7], assuming a Salpeter IMF, to construct the spaHal and spectral light profile of the galaxy. Using the RAMSES output, each star parHcle was assigned a BC03 model spectrum based on its mass, age and metallicity and corrected for the parHcles’ radial velociHes. From the angular co7moving distance at z = 3 we binned the spectra into 1 mas 2 pseudo7spaxels to produce a UV7opHcal rest7 frame spectral cube of the galaxy, with spectral sampling at 1 Å. Finally the cube was redshiUed in wavelength and flux to z = 3. Fig. 2 : (T7L) Radial mass profile of the galaxy, for gas, stars, dark maXer and total; (T7R) Radial density profile of the input galaxy, for stars, gas, dark maXer and combined baryonic maXer. The total mass is 4 x 10 10 M ¯ over a 10x10 kpc region. The black dashed lines indicate the approximate half7mass radius. (B7L) Metallicity distribuHon of the star parHcles in the galaxy; the solar value is indicated with the black dashed line. (B7R) The galaxy’s star formaHon history ploXed as stellar mass vs. formaHon Hme; the red line shows the age of the Universe at z=3. OBSERVATIONS WITH E6ELT HARMONI A typical HARMONI observaHon of our z = 3 galaxy was simulated using a dedicated soUware tool that incorporates realisHc observing parameters and modelled adapHve opHcs PSFs [2]. In this case, we assumed a seeing of 0.67” and observaHons assisted by laser tomographic AO (LTAO). The spectral resolving power was R = 3500, spaxel scale 10 x 10 mas, and we simulated a 2 hour exposure (DIT=600s). The wavelength7integrated output is shown in Fig. 3 for K7band (λ=1.9572.2 µm), corresponding to the rest7frame V7band at z = 3. Using the simulated observaHonal data we will invesHgate how HARMONI will be able to extend dynamical and kinemaHc galaxy studies to the early Universe. This analysis is currently ongoing. Fig. 3 : (L) Slice from the input spectral cube of the z = 3 galaxy, with the flux in each pixel corresponding to the light from star parHcles in the corresponding 1x1 mas on sky. (R) K7 band integrated stellar light image of the galaxy sampled at R=3500 with 10x10 mas spaxels. [1] ThaXe et al, Proc. SPIE vol. 8446, id. 84461L (2012); [2] Zieleniewski et al, Proc. AO4ELT3, Florence (2013); [3] Zieleniewski et al, this conference (2014) ; [4] Pontzen & Governato, Nature vol. 506, 1717178 (2014); [5] Teyssier, A&A 385, 3377364 (2002); [6] Pontzen, Roskar, SHnson & Woods, ASCL 1305.002 (2013); [7] Bruzual & Charlot, MNRAS vol. 344 (4), 100071028 (2003) References
Transcript of Integral)Field)Spectroscopy)of)High6Redshi8)Galaxies)with ... ·...
Integral)Field)Spectroscopy)of)High6Redshi8)Galaxies)with)the)E6ELT)spectrograph)HARMONI)
S.)Kendrew1,)S.)Zieleniewski1,)N.)ThaIe1,)J.)Devriendt1,))R.)Houghton1,))T.)Fusco2,)M.)Tecza1,)F.)Clarke1,)K.)O’Brien1)
1University+of+Oxford,[email protected]++
ABSTRACT)We+ present+ here+ first+ results+ of+ novel+ simulated+ integral+ field+spectroscopic+observaHons+of+ a+ z+ =+ 3+ galaxy+with+HARMONI,+ a+first+ light+ instrument+ for+ the+ 397m+ European+ Extremely+ Large++Telescope.+ Instead+ of+ extrapolaHng+ exisHng+ observaHons+ to+++higher+ z,+ our+ study+ is+ based+ on+ output+ from+ cosmological+simulaHons+with+the+grid7based+adapHve+mesh+refinement+code+RAMSES.+ + Using+ the+ physical+ properHes+ of+ the+ RAMSES+ star+++parHcles+ in+ combinaHon+ with+ stellar+ populaHon+ synthesis++models,+ we+ produced+ a+ 3D+ spectral+ cube+ of+ the+ galaxy’s+starlight.+
A+ HARMONI+ observaHon+ of+ this+ galaxy+ was+ simulated+ using+ a+dedicated+soUware+tool.+We+show+here+details+of+the+input+data+and+ spaHal+ and+ spectral+ light+ properHes,+ and+ simulated+observaHons+ with+ HARMONI.+ This+ work+ will+ demonstrate+ how+HARMONI+will+extend+the+resolved+spectroscopic+and+kinemaHc++study+ of+ galaxies+ to+ the+ early+ Universe,+ and+ show+ how+predicHons+ from+ advanced+ cosmological+ codes+ will+ be+ tested+observaHonally+ at+ high+ redshiUs+ with+ next7generaHon+instruments.++
HARMONI:)INTEGRAL)FIELD)SPECTROSCOPY)WITH)THE)E6ELT)
+The+HARMONI+instrument+(PI:+N.+ThaXe;+[1])+will+provide+IFS+at+visible+and+near7IR+wavelengths+on+the+E7ELT.+Assisted+by+single+conjugate+and+laser+tomographic+AO+(SCAO;+LTAO),+HARMONI+will+achieve+unprecedented+spaHal+resoluHon+over+a+ 6.4+ x+ 9.1”+ field+ of+ view.+ Key+ science+ with+ HARMONI+ covers+ many+ areas+ in+astrophysics,+ from+ characterizaHon+ of+ extrasolar+ panets+ to+ studies+ of+ high7redshiU+galaxies.+To+esHmate+the+scienHfic+performance+of+HARMONI+and+support+the+instrument+design,+ a+ simulator+ was+ developed+ that+ produces+ realisHc+ output+ data+ cubes+[2,3].++
A)SIMULATED)GALAXY)AT)Z=3))SimulaHons+ of+ cosmic+ structure+ formaHon+ allow+ us+ to+ study+ the+ origin+ and+evoluHon+ of+ galaxies+ through+ cosmic+ history.+ Such+ simulaHons+ today+ have+sufficient+ spaHal+ and+ mass+ resoluHon+ to+ make+ quanHtaHve+ observaHonal+predicHons,+and+indeed+pose+challenges+to+the+ΛCDM+paradigm+[4].+We+use+here+output+ from+ one+ such+ simulaHon,+ using+ the+ RAMSES+ code+ [5],+ to+ produce+ a+spectral+ cube+ of+ a+ star7forming+ galaxy+ at+ z+ =+ 3,+ which+ will+ consHtute+ a+ typical+observaHonal+target+for+HARMONI.++Input)Data)We+extracted+a+4+x+1010+Msolar+star7forming+galaxy+from+a+RAMSES+simulaHon+run+terminated+ at+ z+ =+ 3,+ in+ a+ 10+ x+ 10+ kpc+box,+ corresponding+ roughly+ to+ 3+ effecHve+radii.+The+galaxy+is+described+by+2.5+x+106+star,+gas+and+dark+maXer+parHcles;+Fig.+1+shows+the+dark+maXer+and+gas+(baryonic)+density+and+Fig.+2+the+radial+profiles+of+mass+ and+ density,+ as+ well+ as+ properHes+ of+ the+ stars’+ metallicity+ and+ formaHon+history.+ Analysis+ of+ the+ RAMSES+ data+ was+ performed+ using+ Python+ package+pynbody+[6].++
Fig.) 1:+Dark+maXer+density+plot+ (L)+&+detailed+ gas+density+plot+ (R)+ for+ the+ a+ star7forming+galaxy+ at+ z=3,+ as+produced+ in+ cosmological+ simulaHons+with+ the+RAMSES+AMR+code+[5].+
Stellar)popula[ons)We+employ+the+stellar+populaHon+synthesis+models+of+Bruzual+&+Charlot+[BC03;+7],+assuming+a+Salpeter+IMF,+to+construct+the+spaHal+and+spectral+light+profile+of+the+ galaxy.+ Using+ the+ RAMSES+ output,+ each+ star+ parHcle+ was+ assigned+ a+ BC03+model+ spectrum+ based+ on+ its+mass,+ age+ and+metallicity+ and+ corrected+ for+ the+parHcles’+ radial+ velociHes.+ From+ the+ angular+ co7moving+ distance+ at+ z+ =+ 3+ we+binned+ the+ spectra+ into+ 1+ mas2+ pseudo7spaxels+ to+ produce+ a+ UV7opHcal+ rest7frame+spectral+cube+of+the+galaxy,+with+spectral+sampling+at+1+Å.+Finally+the+cube+was+redshiUed+in+wavelength+and+flux+to+z+=+3.+
Fig.)2:+(T7L)+Radial+mass+profile+of+the+galaxy,+for+gas,+stars,+dark+maXer+and+total;+(T7R)+Radial+density+profile+of+the+input+galaxy,+for+stars,+gas,+dark+maXer+and+combined+baryonic+maXer.+The+total+mass+is+4+x+1010+M¯ over+a+10x10+kpc+region.+The+black+dashed+lines+indicate+the+approximate+half7mass+radius.+(B7L)+Metallicity+distribuHon+of+the+star+parHcles+in+the+galaxy;+the+solar+value+is+indicated+with+the+black+dashed+line.+(B7R)+The+galaxy’s+star+formaHon+history+ploXed+as+stellar+mass+vs.+formaHon+Hme;+the+red+line+shows+the+age+of+the+Universe+at+z=3.++
OBSERVATIONS)WITH)E6ELT)HARMONI)A+ typical+ HARMONI+ observaHon+ of+ our+ z+ =+ 3+ galaxy+ was+ simulated+ using+ a+dedicated+ soUware+ tool+ that+ incorporates+ realisHc+ observing+ parameters+ and+modelled+ adapHve+ opHcs+ PSFs+ [2].+ In+ this+ case,+we+ assumed+ a+ seeing+ of+ 0.67”+and+ observaHons+ assisted+ by+ laser+ tomographic+ AO+ (LTAO).+ The+ spectral+resolving+power+was+ +R+=+3500,+spaxel+scale+10+x+10+mas,+and+we+simulated+a+2+hour+exposure+(DIT=600s).+The+wavelength7integrated+output+is+shown+in+Fig.+3+for+K7band+(λ=1.9572.2+µm),+corresponding+to+the+rest7frame+V7band+at+z+=+3.++Using+the+simulated+observaHonal+data+we+will+invesHgate+how+HARMONI+will+be+able+to+extend+dynamical+and+kinemaHc+galaxy+studies+to+the+early+Universe.+This+analysis+is+currently+ongoing.+
Fig.)3:+(L)+Slice+from+the+input++spectral+cube+of+the+z+=+3+galaxy,+with+the+flux+in+each+pixel+corresponding+to+the+light+from+star+parHcles+in+the+corresponding+1x1+mas+on+sky.+(R)+K7band+integrated+stellar+light+image+of+the+galaxy+sampled+at+R=3500+with+10x10+mas+spaxels.+
[1]+ThaXe+et+al,+Proc.+SPIE+vol.+8446,+id.+84461L+(2012);++[2]+Zieleniewski+et+al,+Proc.+AO4ELT3,+Florence+(2013);+[3]+Zieleniewski+et+al,+this+conference+(2014)+;+[4]+Pontzen+&+Governato,+Nature+vol.+506,+1717178+(2014);+[5]+Teyssier,+A&A+385,+3377364+(2002);+[6]+Pontzen,+Roskar,+SHnson+&+Woods,+ASCL+1305.002+(2013);++[7]+Bruzual+&+Charlot,+MNRAS+vol.+344+(4),+100071028+(2003)+
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