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arXiv · 2607.04916

HRMOS: A High-Resolution Multi-Object Spectrograph for the VLT

Laura Magrini·Thomas Bensby·Sofia Randich·Andrea Bianco·Oscar Gonzalez·Emma Fernandez-Alvar·Sergio G. Sousa·Letizia Caito·Marco Riva·Vardan Adibekyan·Anish M. Amarsi·Maria Teresa Belmonte·Maria Benito·Christian P. Clear·Camilla Danielski·Valentina D'Orazi·Riano Giribaldi·Camilla J. Hansen·Vanessa Hill·Robin D. Jeffries·Georges Kordopatis·Andrea Miglio·Dinko Milakovic·Germano Sacco·Jose Schiappacasse-Ulloa·Asa Skuladottir·Rodolfo Smiljanic·Maria Tsantaki·Almudena Arcones·Jose Maria Arroyo-Polonio·Martina Baratella·Beatriz Barbuy·John R. Barnes·Giuseppina Battaglia·Holger Baumgardt·Katia Biazzo·Manuela Bischetti·Angela Bragaglia·Tobias Buck·Sven Buder·Sema Caliskan·Gabriele Cescutti·Andrew Collier Cameron·Ryan Cooke·Sergio Cristallo·Francesco Damiani·Arnas Drazdauskas·Heitor Ernandes·Antonio Frasca·Mark Gieles·Valeria Grisoni·Moira Jardine·Evan N. Kirby·Jonas Klevas·Andreas Korn·Ioanna Koutsouridou·Cis Lagae·Nadege Lagarde·Romain Lucchesi·Francesca Lucertini·Luca Malavolta·Fabiola Marino·Tadafumi Matsuno·Thibault Merle·Sapna Mishra·Marta Molero·Mario Montalto·Michele Moresco·Alessio Mucciarelli·Domenico Nardiello·Valerio Nascimbeni·Brunella Nisini·Joana Oliveira·Elenia Pacetti·Marco Palla·Marco Pignatari·Danae Polychroni·Federico Rizzuti·Donatella Romano·Stefania Salvadori·Luca Sbordone·Emanuele Spitoni·Matthew R. Standing·Grazina Tautvaivsiene·Yuan-Sen Ting·Andrea Travascio·Diego Turrini·Sophie Van Eck·Kim Venn·Diego Vescovi·C. Clare Worley·Nick Wright·Robert Yates·Alice Zocchi·Laura Affer·Carlos Allende·Paul Barklem·Michele Bellazzini·Serena Benatti·Leda Berni
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Abstract

This White Paper presents the scientific rationale and instrument concept for HRMOS (High-Resolution Multi-Object Spectrograph), a next-generation instrument proposed for the ESO Very Large Telescope within the VLT 2030 roadmap. Current and planned facilities offer either multi-object spectroscopy or ultra-high spectral resolution, but not both. HRMOS fills this gap by combining very high spectral resolution, multi-object capability, and radial-velocity stability, enabling transformative studies in Galactic and extragalactic astrophysics. The baseline design provides a resolving power of R = 80000, radial-velocity precision of 10 m s-1 (goal: 5 m s-1), simultaneous observations of 50-60 targets, and broad optical coverage down to 385 nm. These capabilities enable precise measurements of elemental abundances, isotopic ratios, line profiles, and radial velocities for large stellar samples, including crowded fields, star clusters, the Galactic bulge, and nearby dwarf galaxies. HRMOS will address key questions on the age of the oldest stellar populations through nucleocosmochronology, the formation and survival of planetary systems, the assembly history of the Milky Way and satellites, the origin of the heaviest elements, stellar evolution, and the chemical and dynamical properties of the interstellar and circumgalactic medium. It will bridge large spectroscopic surveys and the next generation of extremely large telescopes, with strong synergies with 4MOST, Gaia, TESS, PLATO, the proposed Haydn mission, and future ELT instruments. Building on VLT/FLAMES heritage, HRMOS represents a strategic investment for European astronomy in the 2030s.

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Laura Magrini, Thomas Bensby, Sofia Randich, Andrea Bianco, Oscar Gonzalez, Emma Fernandez-Alvar, Sergio G. Sousa, Letizia Caito, Marco Riva, Vardan Adibekyan, Anish M. Amarsi, Maria Teresa Belmonte, Maria Benito, Christian P. Clear, Camilla Danielski, Valentina D'Orazi, Riano Giribaldi, Camilla J. Hansen, Vanessa Hill, Robin D. Jeffries, Georges Kordopatis, Andrea Miglio, Dinko Milakovic, Germano Sacco, Jose Schiappacasse-Ulloa, Asa Skuladottir, Rodolfo Smiljanic, Maria Tsantaki, Almudena Arcones, Jose Maria Arroyo-Polonio, Martina Baratella, Beatriz Barbuy, John R. Barnes, Giuseppina Battaglia, Holger Baumgardt, Katia Biazzo, Manuela Bischetti, Angela Bragaglia, Tobias Buck, Sven Buder, Sema Caliskan, Gabriele Cescutti, Andrew Collier Cameron, Ryan Cooke, Sergio Cristallo, Francesco Damiani, Arnas Drazdauskas, Heitor Ernandes, Antonio Frasca, Mark Gieles, Valeria Grisoni, Moira Jardine, Evan N. Kirby, Jonas Klevas, Andreas Korn, Ioanna Koutsouridou, Cis Lagae, Nadege Lagarde, Romain Lucchesi, Francesca Lucertini, Luca Malavolta, Fabiola Marino, Tadafumi Matsuno, Thibault Merle, Sapna Mishra, Marta Molero, Mario Montalto, Michele Moresco, Alessio Mucciarelli, Domenico Nardiello, Valerio Nascimbeni, Brunella Nisini, Joana Oliveira, Elenia Pacetti, Marco Palla, Marco Pignatari, Danae Polychroni, Federico Rizzuti, Donatella Romano, Stefania Salvadori, Luca Sbordone, Emanuele Spitoni, Matthew R. Standing, Grazina Tautvaivsiene, Yuan-Sen Ting, Andrea Travascio, Diego Turrini, Sophie Van Eck, Kim Venn, Diego Vescovi, C. Clare Worley, Nick Wright, Robert Yates, Alice Zocchi, Laura Affer, Carlos Allende, Paul Barklem, Michele Bellazzini, Serena Benatti, Leda Berni. 2026-07-06. HRMOS: A High-Resolution Multi-Object Spectrograph for the VLT. https://arxiv.org/abs/2607.04916

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