New version of the HRMOS science white paper
HRMOS is a very high spectral resolution (80k) multi-object (50-60) spectrograph that will be proposed as a next
generation instrument for the VLT. The white paper presents the scientific rationale HRMOS and the instrument concept.
HRMOS (High-Resolution Multi-Object Spectrograph), is a next-generation instrument that will be proposed for the ESO Very
Large Telescope within the VLT Beyond 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 (R = 80 000), multi-object capability (50-60 fibers), optical coverage down to 385 nm, and radial-velocity
stability(5-10 m/s), enabling transformative studies in Galactic and extragalactic astrophysics.
The science cases presented in the White Paper make use of 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.
R. Smiljanic, PI of the SAGA Team, is member of the HRMOS Core Science Team. His participation in the project has received supported
by the OPUS-LAP/WEAVE grant of NCN number 2022/47/I/ST9/02358
entitled "The old Milky Way: a holistic approach for the accurate analysis of metal-poor stars".
Polish Consortium becomes partner of 4MOST!
4MOST is a fibre-fed spectroscopic survey facility installed at the VISTA 4-m telescope of European Southern Observatory (ESO).
The facility is able to simultaneously obtain spectra of ~2400 objects distributed over an hexagonal field-of-view of 4.2 square
degrees.
In June 2026, the Polish 4MOST consortium was awarded funding from the Ministry of Science and Higher Education to confirm its
participation in the 4MOST project. Since then Polish consortium is a partner
of the 4MOST project and the members can additionally indicate one post-doc and any number of PhD students in their group for participation in 4MOST.
As part the scientific programme of 4MOST, Prof. Norbert Christlieb (Universität Heidelberg), co-PI of the Old Milky Way project,
is leading the "Milky Way Halo High Resolution Survey" focused on studying the formation history of the Milky Way, and the earliest
phases of its chemical enrichment, with a sample of 1.5 million stars at high galactic latitude. Thanks to the confirmed participation
in 4MOST, the Polish team of the Old Milky Way project has now also access to data of the survey lead by prof. Christlieb.
Participation at the 4MOST project is funded by
a grant awarded by the Polish Ministry
of Science and Higher Education (MNiSW grant 2026/WK/06).
Project results presented at the 2026 meeting of the EAS
The 2026 annual meeting of the
European Astronomical Society took place between June 29 and July 3 in Lausanne, Switzerland.
As part of “Special Session 33 : Pushing the frontiers: precision spectroscopy of FGK stars”, preliminary results of our
project were presented. R. Smiljanic presented a contributed talk entitled “Accurate atmospheric parameters for
metal-poor stars using flux-calibrated spectra”. This talk presented preliminary results of the analysis of X-Shooter
flux-calibrated spectra being developed by Deepak, postdoc in the team. A paper with the results is now in preparation.
Data Reduction System for the imaging mode of CUBES under development
The CUBES instrument will have
an imaging mode that will allow the flux calibration of the observed spectra. The data reduction system (DRS)
of CUBES will include all the recipes needed for these steps.
As part of our project, we are taking the lead to develop the DRS of the imaging mode. Our participation
is essential to guarantee the high-quality of spectrophotometric calibration of the data for applications
to the analysis of metal-poor stars. For this task, we hired a specialized software development team from
Akond Lab that have experience in software for astronomical data reduction.
Technical camera purchased for the CUBES instrument
CUBES (Cassegrain U-Band Efficient Spectrograph) is a forthcoming ESO VLT spectrograph to be installed at one
Cassegrain focus of the VLT with the goal of covering with a high efficiency the UV ground-based region (300 - 400 nm)
with intermediate resolution (about 20K).
As part of our project, we are taking all the steps to prepare the methodology for the analysis of future observations
of metal-poor stars to be done with CUBES, in particular taking advantage of the spectrophotometric method we are
currently developing. As part of this effort, we purchased the technical camera that will be used in the CUBES acquisition
and guiding (A&G) system. The camera will be used for photometric observations of the science targets and the data will be
part of the flux calibration of the spectra. The camera properties are currently being measured in laboratory.
The selected camera was a Science Grade CCD Camera ELSE-i 1k1k BI UV3 from GreatEyes. It offers the best quantum efficiency
in the needed spectral range for work with CUBES.
Project results presented at the PTA 2025 meeting
Dr. Deepak presented preliminary results of his work as poster contribution in the meeting of the Polish Astronomical
Society in Warsaw, between 8-12 September 2025.
The poster presentation was entitled "Spectro-Photometric Method for Accurate Atmospheric Parameters for Metal-Poor Stars".
It includes preliminary results from our newly developed spectro-photometric method for the accurate estimation of stellar
atmospheric parameters for metal-poor stars included in the X-Shooter spectral library. In this method, we used the Balmer Jump at
3645 A for the estimation of surface gravity in combination with a grid of synthetic spectra generated using the Turbospectrum.
A text on this work was also accepted for publication in the Proceedings of the meeting.
New team member!
Dr. Arthur Alencastro Puls is a new post-doc joining the SAGA team to work on the international collaboration funded by the NCN OPUS/LAP project
"The Old Milky Way: a holistic approach to an accurate analysis of metal-poor stars".
Arthur has a Ph.D. in astrophysics from the Australian National University, Canberra, Australia. He has experience
on using high-resolution spectroscopy, asteroseismology, and dynamics to studies of Galactic Archaeology. After finishing
his Ph.D., he was a postdoc at the Goethe University, working on the abundance of heavy r-process elements in metal-poor stars. Arthur
is joining as a post-doc in
the new OPUS/LAP project that is a collaboration with the group of Norbert Christlieb in Heidelberg, Germany. His work will mainly
concern the analysis of low-resolution spectra of metal-poor stars with a dedicated method employing neural networks.
The "Old Milky Way" project is funded by the National Science Centre, Poland under the OPUS call in the Weave programme,
grant number 2022/47/I/ST9/02358.
Collaboration meeting in Warsaw
The Old Milky collaboration meets between 17-21 of March at CAMK in Warsaw.
In March 2025, the Old Milky Way collaboration is meeting in person. The team members from Heidelberg, Prof. Norbert Christlieb
and Dr. Susmitha Antony, are visiting CAMK/PAN for a week of discussions and hands on work.
In addition, five other researchers with experience in the analysis of metal-poor stars and/or involved in the 4MOST and
CUBES project will visit and join the meeting. Together, the team will review different methods to analyse spectra of metal-poor
stars, discuss what is missing to achieve accurate analysis of metal-poor stars, and establish the steps for the contribution of the OLD-MW project
to be useful for the 4MOST and CUBES spectrographs. The first two days of the meeting will be dedicated to presentations and discussions. The
next three days will be mostly used for hands on work.
Image by
rawpixel.com on Freepik.
We are hiring!
One postdoctoral position is available to join the team and work on a comprehensive spectroscopic study of metal-poor
stars. Deadline is December 6th, 2024.
The successful applicant will join the team and work on the project "The old Milky Way: a holistic approach to an accurate analysis
of metal-poor stars" funded by an OPUS-LAP grant of the Polish National Science Center, nr 2022/47/I/ST9/02358. The project is an
international collaboration with a team lead by Prof. Norbert Christlieb of the Center for Astronomy, University of Heidelberg, Germany.
The overall project aim is to develop a holistic analysis methodology that can be applied to spectra of metal-poor
stars obtained by different instruments and return results that are on a single, consistent scale. The results will be used for a meticulous
study of the properties of the first nucleosynthesis sources of stellar origin in the Universe and to reconstruct the early chemical
evolution of our Galaxy.
The position will focus on the analysis of low-resolution spectra and investigate machine learning methods that can be applied to the
analysis of stellar spectra. This postdoc may also collaborate on work related to 4MOST. Solid experience in some of the following topics
would be assets: machine learning applied to the analysis of stellar spectra, Galactic archaeology, stellar spectroscopy.
Click
here for more details on how to apply.
Image by
storyset on Freepik.
New team member!
Dr. Deepak is a new post-doc joining the SAGA team to work on the international collaboration funded by the NCN OPUS/LAP project
"The Old Milky Way: a holistic approach to an accurate analysis of metal-poor stars".
Deepak has a Ph.D. in astrophysics from the Indian Institute of Astrophysics (IIA), Bengaluru, India, awarded by the Pondicherry
University under an agreement between IIA and the University. Deepak has experience using results from large stellar surveys, like GALAH, LAMOST,
and Gaia, and in using such data to determine stellar properties like kinematics, orbits, masses, and ages. He has several works on
the topic of Li-rich giants and has also worked on stellar substructures in the Galactic disc and halo. He is joining as a post-doc in
the new OPUS/LAP project that is a collaboration with the group of Norbert Christlieb in Heidelberg, Germany. His work will mainly
concern the analysis and simulation of (space- and ground-based) flux-calibrated spectra of metal-poor stars, particularly in
connection to the CUBES spectrograph.
The "Old Milky Way" project is funded by the National Science Centre, Poland under the OPUS call in the Weave programme,
grant number 2022/47/I/ST9/02358.