High-resolu,on Mid-IR Observaons of the Molecular Universe ...
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High-resolu,on Mid-IR Observa,ons of the Molecular Universe with EXES on SOFIA Future Flights and Observing Availability • Cycle 7 (May 2019- Apr 2020) programs just announced. Cycle 8 (May 2020–) call for proposals in fall 2019. Directors Discre,onary Time proposals (e.g. Jovian storms, comets) are accepted at any ,me. • EXES exposure ,me calculator à hTp:// irastro.physics.ucdavis.edu /exes/ etc / • Proposers are encouraged to contact EXES team for advice and assistance. MaThew Richter [email protected] , Cur,s DeWiT cur,[email protected] , Samuel Richards [email protected] • EXES is supported by NASA Collabora,ve Agreement NNX13AI85A. Cur,s DeWiT 1 , MaThew J. Richter 2 , Edward Mon,el 1 , Robert McMurray 3 , Mark McKelvey 4 , Michael Case 1 1 USRA, 2 UC Davis Department of Physics, 3 NASA Ames Research Center 4 SLAC National Accelerator Laboratory Search for Europa’s ice plumes at 6.1 μm The Al R10 echelon gra,ng for EXES (40” x 4”) provides the high dispersion power What is EXES? •Mid-IR High-Resolu,on spectrograph for SOFIA • 1024 x 1024 Si:As detector • 4.5 - 28.3 μm range • 0.5-4% spectral coverage per sefng, depending on choice of cross-disperser and spa,al slit length • Three spectral modes: high (R=100,000) medium (R=15000) and low (R=3000) • Observing modes: nodding & mapping In the high-resolu,on cross-dispersed modes, trade-offs can be made between wavelength coverage and slit length SO 2 gas towards the massive YSO Mon R2 IRS 3 2-D spectral maps are produced by scanning the slit posi,on across an extended source. Here is shown the line emission and con,nuum maps of Jupiter for H 2 S(1) at 17 μm and H 2 S(0) at 28 μm. CS in the hot core AFGL 2591 Mass-loss in the Red Supergiant VY CMa • EXES has set useful upper limits for 3 strong ro-vibra,onal transi,ons of water near 6.1 um including the H 2 O ν 2 1 1,1 -0 0,0 line in March and May 2017, covering the leading and trailing side hemispheres of Europa. *The limits for both dates and hemispheres depend on the assumed gas temperature – for reasonable values seen in cometary gas of 10-100K, the upper limits for numbers of H 2 O molecule are ~5x10 31 (10K) - ~5x10 32 (100K); the implied number of molecules from the HST/STIS transit observa,ons is ~1-2 x 10 32 . . Water plumes detected by HST/ STIS FUV absorp,on against Jupiter (Sparks et al. 2016) •In dense clouds and protostellar environments only a few percent of cosmic sulfur has been iden,fied. •EXES has resolved SO 2 bands previously seen by ISO, finding narrow line widths (<3.2km/s) and T=234 K, loca,ng the gas in a quiescent region close to the protostellar core, where presumably, sulfur-bearing ices have been evaporated, and SO 2 has formed by warm gas-phase chemistry. SO 2 gas accounts for 6% of the sulfur budget. •Similar work is underway for other hot cores with gas-phase SO 2 detec,ons from ISO. •18 transi,ons of CS between R(3) – R(33) were detected by EXES as part of 5.5-8 um hot core spectral survey. •Gas traces close to the inner envelope base of the outlow with H 2 O and 13 CO and 12 CO gas also tracing the same component. T=712K, CS/ 12 CO = 0.008, 10x the submm value •Submm CS traces a cooler, quiescent, more distant component. •Enhanced CS/ 12 CO may arise from sublima,on of H 2 S ice and gas phase reac,ons resul,ng in CS. A small subset of the EXES spectra showing a water P-Cygni profile. The telluric transmission is uncorrected and shown by the dashed red line. Subset of the 5.5-8um spectrum showing a P- Cygni water line profile as well as emission from H 2 18 O. The red dashed line shows the telluric transmission. The rota,onal diagram is complicated by extrac,ng line strengths from P-Cygni profiles. A more complete radia,ve treatment is underway. (Mon,el et al, 2019) VY CMa is an archetypal O-Rich red supergiant, M = 17 +/-8 M ¤ and mass loss rate ~ 10 -4 M ¤ /yr. EXES has taken R=85000 spectra from 5.5-6.8um to probe the mass ejec,ons and beTer understand the composi,on, chemistry, architecture and kinema,cs of the mass loss in these sources. The data set complements spectral survey data taken for the C-rich AGB star, IRC +10216 from 5.5-7.2um. Dungee, et al. “High Resolu-on SOFIA/EXES Spectroscopy of SO2 Gas in the Massive Young Stellar Object MonR2 IRS3: Implica-ons for the Sulfur Budget”. 2018, ApJL, 868, L10 Sparks, et al. “A Search for Water Plumes on Europa with SOFIA”. 2019, ApJL, in press Barr, et al. “Infrared Detec-on of Abundant CS in the Hot Core AFGL 2591 at High Resolu-on with SOFIA/EXES”. 2018, ApJL, 868, L2 Credit: Hubble Legacy Archive; R. Humphreys
Transcript of High-resolu,on Mid-IR Observaons of the Molecular Universe ...
High-resolu,onMid-IRObserva,onsoftheMolecularUniversewithEXESonSOFIA
FutureFlightsandObservingAvailability
• Cycle7(May2019-Apr2020)programsjustannounced.Cycle8(May2020–)callforproposalsinfall2019.DirectorsDiscre,onaryTimeproposals(e.g.Jovianstorms,comets)areacceptedatany,me.
• EXESexposure,mecalculatoràhTp://irastro.physics.ucdavis.edu/exes/etc/• ProposersareencouragedtocontactEXESteamforadviceandassistance.
[email protected],Cur,sDeWiTcur,[email protected],[email protected]• EXESissupportedbyNASACollabora,veAgreementNNX13AI85A.
Cur,sDeWiT1,MaThewJ.Richter2,EdwardMon,el1,RobertMcMurray3,MarkMcKelvey4,MichaelCase11 USRA, 2 UC Davis Department of Physics, 3NASA Ames Research Center 4SLAC National Accelerator Laboratory
SearchforEuropa’siceplumesat6.1µm
TheAlR10echelongra,ngforEXES(40”x4”)providesthehighdispersionpower
WhatisEXES?• Mid-IRHigh-Resolu,onspectrographforSOFIA• 1024x1024Si:Asdetector• 4.5-28.3μmrange• 0.5-4%spectralcoveragepersefng,dependingonchoiceofcross-disperserandspa,alslitlength• Threespectralmodes:high(R=100,000)medium(R=15000)andlow(R=3000)• Observingmodes:nodding&mapping
Inthehigh-resolu,oncross-dispersedmodes,trade-offscanbemadebetweenwavelengthcoverageandslitlength
SO2gastowardsthemassiveYSOMonR2IRS3
2-Dspectralmapsareproducedbyscanningtheslitposi,onacrossanextendedsource.Hereisshownthelineemissionandcon,nuummapsofJupiterforH2S(1)at17µmandH2S(0)at28µm.
CSinthehotcoreAFGL2591 Mass-lossintheRedSupergiantVYCMa
• EXEShassetusefulupperlimitsfor3strongro-vibra,onaltransi,onsofwaternear6.1umincludingtheH2Oν211,1-00,0lineinMarchandMay2017,coveringtheleadingandtrailingsidehemispheresofEuropa.*Thelimitsforbothdatesandhemispheresdependontheassumedgastemperature–forreasonablevaluesseenincometarygasof10-100K,theupperlimitsfornumbersofH2Omoleculeare~5x1031(10K)-~5x1032(100K);theimpliednumberofmoleculesfromtheHST/STIStransitobserva,onsis~1-2x1032.
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WaterplumesdetectedbyHST/STISFUVabsorp,onagainstJupiter(Sparksetal.2016)
• Indensecloudsandprotostellarenvironmentsonlyafewpercentofcosmicsulfurhasbeeniden,fied.• EXEShasresolvedSO2bandspreviouslyseenbyISO,findingnarrowlinewidths(<3.2km/s)andT=234K,loca,ngthegasinaquiescentregionclosetotheprotostellarcore,wherepresumably,sulfur-bearingiceshavebeenevaporated,andSO2hasformedbywarmgas-phasechemistry.SO2gasaccountsfor6%ofthesulfurbudget.• Similarworkisunderwayforotherhotcoreswithgas-phaseSO2detec,onsfromISO.
• 18transi,onsofCSbetweenR(3)–R(33)weredetectedbyEXESaspartof5.5-8umhotcorespectralsurvey.• GastracesclosetotheinnerenvelopebaseoftheoutlowwithH2Oand13COand12COgasalsotracingthesamecomponent.T=712K,CS/12CO=0.008,10xthesubmmvalue• SubmmCStracesacooler,quiescent,moredistantcomponent.• EnhancedCS/12COmayarisefromsublima,onofH2Siceandgasphasereac,onsresul,nginCS.
AsmallsubsetoftheEXESspectrashowingawaterP-Cygniprofile.Thetellurictransmissionisuncorrectedandshownbythedashedredline.
Subsetofthe5.5-8umspectrumshowingaP-CygniwaterlineprofileaswellasemissionfromH2
18O.Thereddashedlineshowsthetellurictransmission.
Therota,onaldiagramiscomplicatedbyextrac,nglinestrengthsfromP-Cygniprofiles.Amorecompleteradia,vetreatmentisunderway.(Mon,eletal,2019)
VYCMaisanarchetypalO-Richredsupergiant,M=17+/-8M¤andmasslossrate~10-4M¤/yr.EXEShastakenR=85000spectrafrom5.5-6.8umtoprobethemassejec,onsandbeTerunderstandthecomposi,on,chemistry,architectureandkinema,csofthemasslossinthesesources.ThedatasetcomplementsspectralsurveydatatakenfortheC-richAGBstar,IRC+10216from5.5-7.2um.
Dungee,etal.“HighResolu-onSOFIA/EXESSpectroscopyofSO2GasintheMassiveYoungStellarObjectMonR2IRS3:Implica-onsfortheSulfurBudget”.2018,ApJL,868,L10
Sparks,etal.“ASearchforWaterPlumesonEuropawithSOFIA”.2019,ApJL,inpress
Barr,etal.“InfraredDetec-onofAbundantCSintheHotCoreAFGL2591atHighResolu-onwithSOFIA/EXES”.2018,ApJL,868,L2
Credit:HubbleLegacyArchive;R.Humphreys
