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Issue 182
Messenger Issue 182

The Messenger Issue 182

Highlights include:

  • Ramsay, S., Cirasuolo, M. et al.: Instrumentation for ESO’s Extremely Large Telescope
  • Mainieri, V., Circosta, C. et al.: SUPER — AGN Feedback at Cosmic Noon: a Multi-phase and Multi-scale Challenge
  • Castro, N., Roth, M. et al.: Mapping the Youngest and Most Massive Stars in the Tarantula Nebula with MUSE-NFM

Read the full PDF

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Table of Content No. 182 | 2021
ELT Instrumentation
Ramsay, S., Cirasuolo, M. et al.
Instrumentation for ESO’s Extremely Large Telescope
ADS BibCode: 2021Msngr.182....3R
Ramsay, S., Cirasuolo, M., Amico, P., Bezawada, N., Caillier, P., Derie, F., Dorn, R., Egner, S., George, E., Gonté, F., Hammersley, P., Haupt, C., Ives, D., Jakob, G., Kerber, F., Mainieri, V., Manescau, A., Oberti, S., Peroux, C., Pfuhl, O., Seemann, U., Siebenmorgen, R., Schmid, C., Vernet, J., The ESO ELT Programme and follow-up team
Design and construction of the instruments for ESO’s Extremely Large Telescope (ELT) began in 2015. We present here a brief overview of the status of the ELT Instrumentation Plan. Dedicated articles on each instrument are presented elsewhere in this volume.

Thatte, N., Tecza, M. et al.
HARMONI: the ELT’s First-Light Near-infrared and Visible Integral Field Spectrograph
ADS BibCode: 2021Msngr.182....7T
Thatte, N., Tecza, M., Schnetler, H., Neichel, B., Melotte, D., Fusco, T., Ferraro-Wood, V., Clarke, F., Bryson, I., O’Brien, K., Mateo, M., Garcia Lorenzo, B., Evans, C., Bouché, N., Arribas, S., The HARMONI Consortium
The High Angular Resolution Monolithic Optical and Near-infrared Integral field spectrograph (HARMONI) is the visible and near-infrared (NIR), adaptive-optics-assisted, integral field spectrograph for ESO’s Extremely Large Telescope (ELT). It will have both a single-conjugate adaptive optics (SCAO) mode (using a single bright natural guide star) and a laser tomographic adaptive optics (LTAO) mode (using multiple laser guide stars), providing near diffraction-limited hyper-spectral imaging. A unique high-contrast adaptive optics with high performance and good sky coverage, respectively (AO) capability has recently been added for exoplanet characterisation. A large detector complement of eight HAWAII-4RG arrays, four choices of spaxel scale, and 11 grating choices with resolving powers ranging from R ~ 3000 to R ~ 17 000 make HARMONI a very versatile instrument that can cater to a wide range of observing programmes.

Ciliegi, P., Agapito, G. et al.
MAORY: A Multi-conjugate Adaptive Optics RelaY for ELT
ADS BibCode: 2021Msngr.182...13C
Ciliegi, P., Agapito, G., Aliverti, M., Annibali, F., Arcidiacono, C., Balestra, A., Baruffolo, A., Bergomi, M., Bianco, A., Bonaglia, M., Busoni, L., Cantiello, M., Cascone, E., Chauvin, G., Chinellato, S., Cianniello, V., Correia, J., Cosentino, G., Dall’Ora, M., De Caprio, V., Devaney, N., Di Antonio, I., Di Cianno, A., Di Giammatteo, U., D’Orazi, V., Di Rico, G., Dolci, M., Doutè, S., Eredia, C., Farinato, J., Esposito, S., Fantinel, D., Feautrier, P., Foppiani, I., Giro, E., Gluck, L., Golden, A., Goncharov, A., Grani, P., Gullieuszik, M., Haguenauer, P., Hénault, F., Hubert, Z., Le Louran, M., Magrin, D., Maiorano, E., Mannucci, F., Malone, D., Marafatto, L., Moraux, E., Munari, M., Oberti, S., Pariani, G., Pettazzi, L., Plantet, C., Podio, L., Portaluri, E., Puglisi, A., Ragazzoni, R., Rakich, A., Rabou, P., Redaelli, E., Redman, M., Riva, M., Rochat, S., Rodeghiero, G., Salasnich, B., Saracco, P., Sordo, R., Spavone, M., Sztefek, M., Valentini, A., Vanzella, E., Verinaud, C., Xompero, M., Zaggia, S.
The Multi-conjugate Adaptive Optics RelaY (MAORY) is the adaptive optics (AO) module for the Extremely Large Telescope (ELT) that will provide two gravity-invariant ports with the same optical quality for two different client instruments. It will enable high-angular-resolution observations in the near-infrared over a large field of view (~ 1 arcminute2) by real-time compensation of the wavefront distortions caused by atmospheric turbulence. Wavefront sensing is performed using laser and natural guide stars while the wavefront sensor compensation is performed by an adaptive deformable mirror (DM) in MAORY which works together with the telescope’s adaptive and tip-tilt mirrors M4 and M5 respectively.

Davies, R., Hörmann, V. et al.
MICADO: The Multi-Adaptive Optics Camera for Deep Observations
ADS BibCode: 2021Msngr.182...17D
Davies, R., Hörmann, V., Rabien, S., Sturm, E., Alves, J., Clénet, Y., Kotilainen, J., Lang-Bardl, F., Nicklas, H., Pott, J., Tolstoy, E., Vulcani, B., The MICADO Consortium
The Multi-adaptive optics Imaging CamerA for Deep Observations (MICADO) will image a field of view of nearly 1 arcminute at the diffraction limit of the Extremely Large Telescope (ELT), making use of the adaptive optics correction provided by single-conjugate adaptive optics (SCAO) and multi-conjugate adaptive optics (MCAO). Its simple and robust design will yield an unprecedented combination of sensitivity and resolution across the field. This article outlines the characteristics of the observing modes offered and illustrates each of them with an astrophysical application. Potential users can explore their own ideas using the data simulator ScopeSim.

Brandl, B., Bettonvil, F. et al.
METIS: The Mid-infrared ELT Imager and Spectrograph
ADS BibCode: 2021Msngr.182...22B
Brandl, B., Bettonvil, F., van Boekel, R., Glauser, A., Quanz, S., Absil, O., Amorim, A., Feldt, M., Glasse, A., Güdel, M., Ho, P., Labadie, L., Meyer, M., Pantin, E., van Winckel, H., The METIS Consortium
The Mid-infrared ELT Imager and Spectrograph (METIS) will provide the Extremely Large Telescope (ELT) with a unique window to the thermal- and mid-infrared (3–13 µm). Its single-conjugate adaptive optics (SCAO) system will enable high contrast imaging and integral field unit (IFU) spectroscopy (R ~ 100 000) at the diffraction limit of the ELT. This article describes the science drivers, conceptual design, observing modes, and expected performance of METIS.

Marconi, A., Abreu, M. et al.
HIRES, the High-resolution Spectrograph for the ELT
ADS BibCode: 2021Msngr.182...27M
Marconi, A., Abreu, M., Adibekyan, V., Aliverti, M., Allende Prieto, C., Amado, P., Amate, M., Artigau, E., Augusto, S., Barros, S., Becerril, S., Benneke, B., Bergin, E., Berio, P., Bezawada, N., Boisse, I., Bonfils, X., Bouchy, F., Broeg, C., Cabral, A., Calvo-Ortega, R., Canto Martins, B., Chazelas, B., Chiavassa, A., Christensen, L., Cirami, R., Coretti, I., Covino, S., Cresci, G., Cristiani, S., Cunha Parro, V., Cupani, G., de Castro Leão, I., Renan de Medeiros, J., Furlande Souza, M., Di Marcantonio, P., Di Varano, I., D’Odorico, V., Doyon, R., Drass, H., Figueira, P., Belen Fragoso, A., Uldall Fynbo, J., Gallo, E., Genoni, M., González Hernández, J., Haehnelt, M., Hlavacek-Larrondo, J., Hughes, I., Huke, P., Humphrey, A., Kjeldsen, H., Korn, A., Kouach, D., Landoni, M., Liske, J., Lovis, C., Lunney, D., Maiolino, R., Malo, L., Marquart, T., Martins, C., Mason, E., Molaro, P., Monnier, J., Monteiro, M., Mordasini, C., Morris, T., Mucciarelli, A., Murray, G., Niedzielski, A., Nunes, N., Oliva, E., Origlia, L., Pallé, E., Pariani, G., Parr-Burman, P., Peñate, J., Pepe, F., Pinna, E., Piskunov, N., Rasilla Piñeiro, J., Rebolo, R., Rees, P., Reiners, A., Riva, M., Romano, D., Rousseau, S., Sanna, N., Santos, N., Sarajlic, M., Shen, T., Sortino, F., Sosnowska, D., Sousa, S., Stempels, E., Strassmeier, K., Tenegi, F., Tozzi, A., Udry, S., Valenziano, L., Vanzi, L., Weber, M., Woche, M., Xompero, M., Zackrisson, E., Zapatero Osorio, M.
HIRES will be the high-resolution spectrograph at optical and near-infrared (NIR) wavelengths for ESO’s Extremely Large Telescope (ELT). It will consist of three fibre-fed spectrographs providing a wavelength coverage of 0.4–1.8 µm (with a goal of 0.35–1.8 µm) at a spectral resolution of ~ 100 000. Fibre-feeding allows HIRES to have several interchangeable observing modes, including a single-conjugate adaptive optics (SCAO) module and a small diffraction-limited integral field unit in the NIR. It will therefore be able to operate in both seeing- and diffraction-limited modes. HIRES will address a wide range of science cases spanning nearly all areas of research in astrophysics and even fundamental physics. Some of the top science cases will be the detection of biosignatures from exoplanet atmospheres, finding the fingerprints of the first generation of stars (Pop III), tests on the stability of Nature’s fundamental couplings, and the direct detection of the cosmic acceleration. The HIRES consortium is composed of more than 30 institutes from 14 countries, forming a team of more than 200 scientists and engineers.

Hammer, F., Morris, S. et al.
MOSAIC on the ELT: High-multiplex Spectroscopy to Unravel the Physics of Stars and Galaxies from the Dark Ages to the Present Day
ADS BibCode: 2021Msngr.182...33H
Hammer, F., Morris, S., Cuby, J., Kaper, L., Steinmetz, M., Afonso, J., Barbuy, B., Bergin, E., Finogenov, A., Gallego, J., Kassin, S., Miller, C., Östlin, G., Pentericci, L., Schaerer, D., Ziegler, B., Chemla, F., Dalton, G., De Frondat, F., Evans, C., Le Mignant, D., Puech, M., Rodrigues, M., Sanchez-Janssen, R., Taburet, S., Tasca, L., Yang, Y., Zanchetta, S., Dohlen, K., Dubbeldam, M., El Hadi, K., Janssen, A., Kelz, A., Larrieu, M., Lewis, I., MacIntosh, M., Morris, T., Navarro, R., Seifert, W.
The powerful combination of the cutting-edge multi-object spectrograph named MOSAIC with the world largest visible/near-infrared telescope, ESO’s Extremely Large Telescope (ELT), will allow us to probe deeper into the Universe than ever before. MOSAIC is an extremely efficient instrument for obtaining spectra of the numerous faint sources in the Universe, including the very first galaxies and sources of cosmic reionisation. MOSAIC has a high multiplex in the near-infrared (NIR) and in the visible, and also has multi-integral field units (Multi-IFUs) in the NIR. It is therefore perfectly suited to carrying out an inventory of dark matter (from rotation curves) and baryons in the cool–warm gas phases in galactic haloes at z = 3–4. MOSAIC will enable detailed maps of the intergalactic medium at z = 3, the evolutionary history of dwarf galaxies during a Hubble time, and the chemistry as directly measured from stars up to several Mpc. It will also measure faint features in cluster gravitational lenses or in streams surrounding nearby galactic haloes. The preliminary design of MOSAIC is expected to begin next year and its level of readiness is already high, given the instrumental studies already carried out by the team.

Kasper, M., Cerpa Urra, N. et al.
PCS — A Roadmap for Exoearth Imaging with the ELT
ADS BibCode: 2021Msngr.182...38K
Kasper, M., Cerpa Urra, N., Pathak, P., Bonse, M., Nousiainen, J., Engler, B., Heritier, C., Kammerer, J., Leveratto, S., Rajani, C., Bristow, P., Le Louarn, M., Madec, P., Ströbele, S., Verinaud, C., Glauser, A., Quanz, S., Helin, T., Keller, C., Snik, F., Boccaletti, A., Chauvin, G., Mouillet, D., Kulcsár, C., Raynaud, H.
The Planetary Camera and Spectrograph (PCS) for the Extremely Large Telescope (ELT) will be dedicated to detecting and characterising nearby exoplanets with sizes from sub-Neptune to Earth-size in the neighbourhood of the Sun. This goal is achieved by a combination of eXtreme Adaptive Optics (XAO), coronagraphy and spectroscopy. PCS will allow us not only to take images, but also to look for biosignatures such as molecular oxygen in the exoplanets’ atmospheres. This article describes the PCS primary science goals, the instrument concept and the research and development activities that will be carried out over the coming years.

Astronomical Science
Mainieri, V., Circosta, C. et al.
SUPER — AGN Feedback at Cosmic Noon: a Multi-phase and Multi-scale Challenge
ADS BibCode: 2021Msngr.182...45M
Mainieri, V., Circosta, C., Kakkad, D., Perna, M., Vietri, G., Bongiorno, A., Brusa, M., Carniani, S., Cicone, C., Civano, F., Comastri, A., Cresci, G., Feruglio, C., Fiore, F., Georgakakis, A., Harrison, C., Husemann, B., Lamastra, A., Lamperti, I., Lanzuisi, G., Mannucci, F., Marconi, A., Menci, N., Merloni, A., Netzer, H., Padovani, P., Piconcelli, E., Puglisi, A., Salvato, M., Scholtz, J., Schramm, M., Silverman, J., Vignali, C., Zamorani, G., Zappacosta, L.
Theoretical models of galaxy evolution suggest that galaxy-wide outflows driven by active galactic nuclei (AGN), one of the so-called AGN-feedback mechanisms, are a fundamental process affecting the bulk of the baryons in the Universe. While the presence of such outflows out to kpc scales is now undisputed, their impact on the star formation, gas content and kinematics of the host galaxy is hotly debated. Here we report on the results from our Large Programme SUPER, which used the Spectrograph for INtegral Field Observations in the Near INfrared (SINFONI) on the Very Large Telescope (VLT) to carry out the first statistically sound high-spatial-resolution investigation of AGN outflows at z ~ 2, covering four orders of magnitude in AGN bolometric luminosity.

Castro, N., Roth, M. et al.
Mapping the Youngest and Most Massive Stars in the Tarantula Nebula with MUSE-NFM
ADS BibCode: 2021Msngr.182...50C
Castro, N., Roth, M., Weilbacher, P., Micheva, G., Monreal-Ibero, A., Kelz, A., Kamann, S., Maseda, M., Wendt, M., The MUSE collaboration
The evolution of the most massive stars is a puzzle with many missing pieces. Statistical analyses are key to providing anchors to calibrate theory, but performing these studies is an arduous job. The state-of-the-art integral field spectrograph Multi Unit Spectroscopic Explorer (MUSE) has stirred up stellar astrophysicists, who are excited about its ability to take spectra of up to a thousand stars in a single exposure. The excitement was even greater with the commissioning of the MUSE narrow-field mode (MUSE-NFM) that has demonstrated angular resolution akin to that of the Hubble Space Telescope (HST). We present the first mapping of the dense stellar core R136 in the Tarantula nebula based on a MUSE-NFM mosaic. We aim to deliver the first homogeneous analysis of the most massive stars in the local Universe and to explore the impact of these peculiar objects on the interstellar medium (ISM).

Astronomical News
Berg, T., Ribas, Á.
Fellows at ESO
ADS BibCode: 2021Msngr.182...55E
Berg, T., Ribas, Á.

Zerbi, F., Fontana, A.
In memoriam Nichi D’Amico
ADS BibCode: 2021Msngr.182...57Z
Zerbi, F., Fontana, A.

Lyubenova, M.
Message from the Editor
ADS BibCode: 2021Msngr.182...58L
Lyubenova, M.

Personnel Movements
ADS BibCode: 2021Msngr.182...60E

Annual Index 2020 (Nos. 179–181)
ADS BibCode: 2021Msngr.182...61E