IAU-H1 Seminar 2025 October 15th.SHARP - A new-generation multi-mode Near-IR spectrograph for the Extremely Large Telescope to unlock the Universe at unprecedented scales

An advanced Near-IR multi-mode spectrograph for the ELT Unlocking the Universe at unprecedented scales Paolo Saracco INAF - Osservatorio Astronomico di Brera & the SHARP Team SHARP - sharp.brera.inaf.it •What is SHARP •The Near-IR spectroscopy in the 2030s •Why SHARP •SHARP Properties and Capabilities •Science with SHARP •Project status and prospects Paolo Saracco Layout IAU-H1 Oct 2025 What is SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 SHARP - sharp.brera.inaf.it Paolo Saracco What is SHARP IAU-H1 Oct 2025 NEXUS Multi-Object Spectrograph Configurable Slit System VESPER Multi-Integral Field Unit A Near-IR multi-mode spectrograph conceived to exploit the ELT aperture Multi-Conjugate Adaptive Optics Module Provides a uniform near-IR AO correction (FWHM~0.012”) over a FoV~1.8’x1.8’ SHARP will be proposed in the next ESO call Expanding Horizons 0.95-2.45 mu MCAO (MORFEO) SHARP NEXUS MOS VESPER mIFU Not fiber fed to reach the faintest reachable fluxes at the sharpest angular resolution over the widest AO corrected field. MCAO Focal plane Unit Selector System ADC = Atmospheric Dispersion Corrector NGS = Natural Guide Stars Unit SHARP in a Nutshell (2.4” length) MCAO (MORFEO) SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 6 Spectrograph AO Multi Plex Type FoV Ang res (mas) Wavelength (μm) Comm  /Δ 2030 2034 2039 2044 JWST-NIRSpec - ~100 MSA 3’x3’ 100 Pixel size 0.6-5.0 100-2700 ? JWST-NIRSpec - 1 IFU 3”x3” 100 Pixel size 0.6-5.0 100-2700 ? ELT-MICADO SCAO MCAO 1 Longslit sw<50 mas 12 diff lim ELT 0.85-2.4 20000 ELT-HARMONY MCAO 1 IFU 3”x4” 20 pixel size 0.9-2.4 ? 30007000? ? ? ELT-ANDES SCAO 1 IFU 0.5”x0.5” 12 diff lim ELT 1.0-1.8 Fiber 100000 ELT-MOSAIC MOAO 8 multi-IFU 2.2”x2.2” 80/ 150 fiber/MOAO 1.0-1.8 Fiber 5000-20000 ? GMTIFS LTAO 1 IFU <3”x4” 50 Pixel size 0.9-2.4 5000-10000 SHARP-NEXUS MCAO ~30 MOS 1’.2x1’.2 35 Pixel size 0.95-2.4 ~200-6000 SHARP-VESPER MCAO 12 multiIFU 1.7”x1.5” 31 Pixel Size 1.2-2.4 ~3000 ELTs High-Ang resolution spectrographs in the 2030s-2040s SCAO: 0.012” on-axis, Strehl ratio >0.8, 1 Natural Guide Star (NGS)<16 mag within 15” MCAO: 0.012” uniformly over ~2’x2’, Strehl ratio ~0.5, 1-3 NGS<21 mag within ~80” + 6 Laser GS GLAO/MOAO: ~0.15” over the field, (M4+M5 mirrors) seeing limited correction (enhanced seeing mode) None of the planned spectrographs is able to follow the paths opened by JWST Why Scientific Rational and Main Requirements SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 Understanding how baryons assemble to form stars, galaxies and structures, how these evolve over cosmic time. SOME KEY QUESTIONS •Globular Clusters (GC) •multiple stellar populations. Which are the mechanism(s) for the formation of the II generation of stars? •Are GCs remnants of SF events in the early universe, or did they form in a more continuous process? •Initial Mass Function (IMF): What physical processes determine the shape of the IMF? Transition between low-mass and high-mass stars? •Milky Way Structure: What is the origin of the Galactic Bulge (classical bulge vs pseudo-bulge) ? •What regulates quenching of star formation and what keep quenched a galaxy ? •What are the extreme physical conditions governing star formation in the early Universe ? •What is the dark matter content of galaxies ? •What is the physical interplay between black holes and galaxies ? •“Where is” the elusive PopIII of primordial stars ? •.................. MOST OF THE FUNDAMENTAL INFORMATION IS STORED IN THE SPECTRA Why SHARP - Rationale SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 Rome, July 2025 Why NIR at High-Angular resolution NIR is essential for seeing through dust, high angular resolution for resolving individual sources. Massive star cluster in the Milky Way Star formation around the sun Orion 1” NIRCam http://sharp.brera.inaf.it 80% of light extinguished Westerlund 1 Why Near-IR (Local Universe) Spatialy resolved spectroscopy of massive star forming environments Highly extinguished and crowded SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 2 IFS JWST NIRCam NEXUS NEXUS - The multi-Object Spectrograph Inversion Prism Rotates the field subtended by the slit. Adjustable rotation angle SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 Rome, July 2025 http://sharp.brera.inaf.it SHARP SHARP Optical Design SHARP Optical design SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 Unit Selector System -Configurable Slit System (NEXUS) -Field Selection System (VESPER) Rome, July 2025 http://sharp.brera.inaf.it SHARP Optical-Mechanical Design Unit Selector System -Configurable Slit System (NEXUS) -Field Selection System (VESPER) SHARP Opto-mechanical design Mahmoodzadeh et al. 2025 SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 SHARP - sharp.brera.inaf.it Science with Paolo Saracco Rome, July 2025 http://sharp.brera.inaf.it SHARP Optical-Mechanical Design SHARP Angular scales and physical sizes SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 0.031” 1”.7 NEXUS 72” VESPER 24” Comet NEOWISE - Photograph by JUAN CARLOS CASADO, SCIENCE PHOTO LIBRARY • Frozen fossils from the solar system formation • Provides key insights into the physical, chemical, and evolutionary processes that shaped our and other planetary systems. • It can reveal whether the material in our Solar System was primarily inherited from the proto-solar nebula or reprocessed during its formation. SHARP Investigations of Comets Comets composition Nature and behaviour of comets still poorly understood: 1. how the ices are stored in a comet nucleus; 2. how they are released as the comet approaches the Sun; 3. How gas and refractory material transform in the coma and tails after being released. Credits: M. Lippi Simultaneous observations of nucleus, coma and tails: 1. distinguish between primary, secondary, and extended sources, and understand their formation paths 2. retrieve instantaneous 2D maps of molecular abundance, temperature, and velocity across the entire active region 3. capture the full morphology of gas and dust jets as they evolve in the coma and tails. Example of 6 FSs pointings: from the nucleus to the coma and tail. VESPER can use up to 12 probes in different positions to further cover different part of the active comet. SHARP Investigations of Comets Probes pointing the ion tail to study photodissociation processes and interactions with the solar wind Coma pointings, to investigate dust properties and secondary molecules => photodissociation and recombination Pointing the nucleus, to study primary molecules VESPER ideal to investigate the processes related to comet activity How the ices and dust are stored in the nucleus ==> how planetesimals formed in our protoplanetary disk. Credits: M. Lippi 1) Central bulge: classical bulge or disk evolution? 3D morphology using SHARP-NEXUS Central(left panels) vs. Inner bulge(right panels); chemo-dynamics; Han&WangHF+2025; WangHF, in prep. Long bar+thick bulge argument; L0pez-Corredoira+2007Star counts and Line of sight. Lopez-Corredoira, In prep. Near-Infrared; Higher spatial resolution; Red giants or variable stars@SHARP Unveiling the Origins of the Milky Way Bulge Credits: H. Wang What causes Magellanic Stream (MS) ? Tidal Model: Magellanic Stream (MS) is due to tidal interactions between the LMC and SMC. Supporting evidence: the MS does not follow the LMC’s proper motion vector, as would be expected for a purely ram-pressure tail (Besla et al. 2012). Ram Pressure + Collision Model: Combined “Ram Pressure + Collision” scenario, where the MS originates from interactions of the Magellanic Clouds with the Milky Way’s hot halo gas (Hammer et al. 2015) Observations of stellar and gas metallicities with SHARP: NEXUS: the multi-object spectrograph for stars 6D information; VESPER: the multi-integral field unit (spatial pixel scale is 31 mas) for ionised gas and High velocity clouds. Hammer+2015 Credits: H. Wang Unlocking the Origin of the Magellanic Stream What are the effects of the local environment on the properties of the forming stars? What are the IMF, mass accretion rate & disk lifetime in low-metallicity environments? Agreement with Solar metallicity IMF for M > 0.3 M☉ Very uncertain in the low-mass and sub-stellar regimes IMF at low-Z not determined yet Yasui et al. 2009 Accretion & disk lifetime vs Metallicity Disks & Jets in low-Z SFRs Much lower disk fraction at low Z (< 0.2 Z☉) indicates shorter disks lifetime Lower mass accretion rates at low-Z? Accretion/ejection & disk properties at low-Z How this affects planet formation? McLeod et al. 2024 Star Formation process from nearby SFRs to the outskirts of the MW and beyond Credits: L. Podio Objectives SHARP needs an International Consortium to grow We are open to collaboration with •potentially interested foreign institutes •individual researchers http://sharp.brera.inaf.it [email protected] [email protected] Collection of scientific cases showcasing the instrument’s capabilities in various areas New Astronomy Journal (Elsivier) We invite anyone interested to submit a scientific case for SHARP SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 https://sharp.brera.inaf.it/science-book/ Ambitions SHARP exceeds the observational limits fixed by NIRSpec@JWST allowing us to explore the new paths that JWST is opening. SHARP can take up the baton left by JWST when its mission ends. SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 "Why Everest?" - "Because it's there" G. Mallory, 1924 Thank you! This is SHARP SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 Paolo Saracco SHARP - sharp.brera.inaf.it Backup Rome, July 2025 http://sharp.brera.inaf.it SHARP NEXUS VESPER SHARP Optical Design SHARP Optical design SHARP - sharp.brera.inaf.it Paolo Saracco IAU-H1 Oct 2025 Paolo Saracco SHARP - sharp.brera.inaf.it Conifurable slit system Configurable slit-mask unit for the Keck telescope (near-IR cryogenic camera MOSFIRE) designed and manufactured by CSEM co. Slicer SHARP - sharp.brera.inaf.it 2 IFS 2 groups 72+72 mirrors Corresponding 72+72 pupil mirrors. Slicer on the focal plane (similar to MUSE) 288 mirrors, devided into 4 groups; Optical design by Paolo Conconi Paolo Saracco VESPER - The multi-IFU Each group samples a stripe of the image 4 groups --> 4 stripes --> 4 cameras SHARP - sharp.brera.inaf.it VESPER Slicer 1 3 4 1.5” 1.5” MUSE mirrors (0.8mm) and pupil mirrors Mirrors Pupil Mirrors Paolo Saracco SHARP - sharp.brera.inaf.it AO PSF is made up of two components: 1. Diffraction limited core 2. Seeing-limited halo Strehl Ratio SR = Iactual_PSF/Idl_PSF = intensity peak actual PSF / diff-lim PSF SCAO: Single Conjugate AO, on-axis correction, 1 Natural Guide Star (NGS)<16 mag within 15” MCAO: Multi Conjugate AO, ~2’x2’ corrected, 1-3 NGS<21 mag within ~80” + 6 Laser GS GLAO: Ground Layer AO (M4+M5), seeing limited correction (enhanced seeing) FWHMELT = 0.012 arcsec FWHMJWST = 0.070 arcsec At λ=2.2 mu (K band) FWHMdl=1.22 λ/D AO system FWHM (arcsec) SR SCAO 0.012 >0.8 on-axis MCAO 0.012 ~0.6 F.o.V. GLAO ~0.2 ...... AO System (ELT-ETC) Texp (s) HAB=25 Texp (s) KAB=25 Radius of SN area (mas) MCAO 30 90 20 GLAO 630 5280 150 Gain (Texp) ~20 ~58 (point source) MCAO ~20(>50) times more efficient than GLAO in H(K)-band Paolo Saracco Overview: AO systems at ELT