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1. NIRPS first light and early science: breaking the 1 m/s RV precision barrier at infrared wavelengths

Author

Artigau, Étienne, Bouchy, François, Doyon, René, Baron, Frédérique, Malo, Lison, Wildi, François, Pepe, Franceso, Cook, Neil J., Thibault, Simon, Reshetov, Vladimir, Dumusque, Xavier, Lovis, Christophe, Sosnowska, Danuta, Martins, Bruno L. Canto, De Medeiros, Jose Renan, Delfosse, Xavier, Santos, Nuno, Rebolo, Rafael, Abreu, Manuel, Allain, Guillaume, Allart, Romain, Auger, Hugues, Barros, Susana, Bazinet, Luc, Blind, Nicolas, Boisse, Isabelle, Bonfils, Xavier, Bourrier, Vincent, Bovay, Sébastien, Broeg, Christopher, Brousseau, Denis, Bruniquel, Vincent, Cabral, Alexandre, Cadieux, Charles, Carmona, Andres, Carteret, Yann, Challita, Zalpha, Chazelas, Bruno, Cloutier, Ryan, Coelho, João, Cointepas, Marion, Conod, Uriel, Cowan, Nicolas, Cristo, Eduardo, da Silva, João Gomes, Dauplaise, Laurie, Gomes, Roseane de Lima, Delgado-Mena, Elisa, Ehrenreich, David, Faria, João, Figueira, Pedro, Forveille, Thierry, Frensch, Yolanda, Gagné, Jonathan, Genest, Frédéric, Genolet, Ludovic, Hernández, Jonay I. González, Témich, Félix Gracia, Grieves, Nolan, Hernandez, Olivier, Hobson, Melissa J., Hoeijmakers, Jens, Kerley, Dan, Krishnamurthy, Vigneshwaran, Lafrenière, David, Lamontagne, Pierrot, Larue, Pierre, Leaf, Henry, Leão, Izan C., Lim, Olivia, Curto, Gaspare Lo, Martins, Allan M., Melo, Claudio, Messias, Yuri S., Mignon, Lucile, Moranta, Leslie, Mordasini, Christoph, Moulla, Khaled Al, Mounzer, Dany, L'Heureux, Alexandrine, Nari, Nicola, Nielsen, Louise, Osborn, Ares, Parc, Léna, Pasquini, Luca, Passegger, Vera M., Pelletier, Stefan, Peroux, Céline, Piaulet, Caroline, Plotnykov, Mykhaylo, Poulin-Girard, Anne-Sophie, Rasilla, José Luis, Saint-Antoine, Jonathan, Sarajlic, Mirsad, Segovia, Alex, Seidel, Julia, Ségransan, Damien, Silva, Ana Rita Costa, Srivastava, Avidaan, Stefanov, Atanas K., Mascareño, Alejandro Suárez, Sordet, Michael, Teixeira, Márcio A., Udry, Stéphane, Valencia, Diana, Vallée, Philippe, Vandal, Thomas, Vaulato, Valentina, Wade, Gregg, Wardenier, Joost P., Wehbé, Bachar, Weisserman, Drew, Wevers, Ivan, and Zins, Gérard

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

The Near-InfraRed Planet Searcher or NIRPS is a precision radial velocity spectrograph developed through collaborative efforts among laboratories in Switzerland, Canada, Brazil, France, Portugal and Spain. NIRPS extends to the 0.98-1.8 $\mu$m domain of the pioneering HARPS instrument at the La Silla 3.6-m telescope in Chile and it has achieved unparalleled precision, measuring stellar radial velocities in the infrared with accuracy better than 1 m/s. NIRPS can be used either stand-alone or simultaneously with HARPS. Commissioned in late 2022 and early 2023, NIRPS embarked on a 5-year Guaranteed Time Observation (GTO) program in April 2023, spanning 720 observing nights. This program focuses on planetary systems around M dwarfs, encompassing both the immediate solar vicinity and transit follow-ups, alongside transit and emission spectroscopy observations. We highlight NIRPS's current performances and the insights gained during its deployment at the telescope. The lessons learned and successes achieved contribute to the ongoing advancement of precision radial velocity measurements and high spectral fidelity, further solidifying NIRPS' role in the forefront of the field of exoplanets., Comment: Proceeding at the SPIE Astronomical Telescopes + Instrumentation conference [Yokohama,Japan; June 2024]

Published
2024

2. The PLATO Mission

Author

Rauer, Heike, Aerts, Conny, Cabrera, Juan, Deleuil, Magali, Erikson, Anders, Gizon, Laurent, Goupil, Mariejo, Heras, Ana, Lorenzo-Alvarez, Jose, Marliani, Filippo, Martin-Garcia, César, Mas-Hesse, J. Miguel, O'Rourke, Laurence, Osborn, Hugh, Pagano, Isabella, Piotto, Giampaolo, Pollacco, Don, Ragazzoni, Roberto, Ramsay, Gavin, Udry, Stéphane, Appourchaux, Thierry, Benz, Willy, Brandeker, Alexis, Güdel, Manuel, Janot-Pacheco, Eduardo, Kabath, Petr, Kjeldsen, Hans, Min, Michiel, Santos, Nuno, Smith, Alan, Suarez, Juan-Carlos, Werner, Stephanie C., Aboudan, Alessio, Abreu, Manuel, a, Lorena Acu, Adams, Moritz, Adibekyan, Vardan, Affer, Laura, Agneray, François, Agnor, Craig, Børsen-Koch, Victor Aguirre, Ahmed, Saad, Aigrain, Suzanne, Al-Bahlawan, Ashraf, Gil, M de los Angeles Alcacera, Alei, Eleonora, Alencar, Silvia, Alexander, Richard, Alfonso-Garzón, Julia, Alibert, Yann, Prieto, Carlos Allende, Almeida, Leonardo, Sobrino, Roi Alonso, Altavilla, Giuseppe, Althaus, Christian, Trujillo, Luis Alonso Alvarez, Amarsi, Anish, Eiff, Matthias Ammler-von, Amôres, Eduardo, Andrade, Laerte, Antoniadis-Karnavas, Alexandros, António, Carlos, del Moral, Beatriz Aparicio, Appolloni, Matteo, Arena, Claudio, Armstrong, David, Aliaga, Jose Aroca, Asplund, Martin, Audenaert, Jeroen, Auricchio, Natalia, Avelino, Pedro, Baeke, Ann, Baillié, Kevin, Balado, Ana, Balagueró, Pau Ballber, Balestra, Andrea, Ball, Warrick, Ballans, Herve, Ballot, Jerome, Barban, Caroline, Barbary, Gaële, Barbieri, Mauro, Forteza, Sebasti Barceló, Barker, Adrian, Barklem, Paul, Barnes, Sydney, Navascues, David Barrado, Barragan, Oscar, Baruteau, Clément, Basu, Sarbani, Baudin, Frederic, Baumeister, Philipp, Bayliss, Daniel, Bazot, Michael, Beck, Paul G., Bedding, Tim, Belkacem, Kevin, Bellinger, Earl, Benatti, Serena, Benomar, Othman, Bérard, Diane, Bergemann, Maria, Bergomi, Maria, Bernardo, Pierre, Biazzo, Katia, Bignamini, Andrea, Bigot, Lionel, Billot, Nicolas, Binet, Martin, Biondi, David, Biondi, Federico, Birch, Aaron C., Bitsch, Bertram, Ceballos, Paz Victoria Bluhm, Bódi, Attila, Bognár, Zsófia, Boisse, Isabelle, Bolmont, Emeline, Bonanno, Alfio, Bonavita, Mariangela, Bonfanti, Andrea, Bonfils, Xavier, Bonito, Rosaria, Bonomo, Aldo Stefano, Börner, Anko, Saikia, Sudeshna Boro, Martín, Elisa Borreguero, Borsa, Francesco, Borsato, Luca, Bossini, Diego, Bouchy, Francois, Boué, Gwenaël, Boufleur, Rodrigo, Boumier, Patrick, Bourrier, Vincent, Bowman, Dominic M., Bozzo, Enrico, Bradley, Louisa, Bray, John, Bressan, Alessandro, Breton, Sylvain, Brienza, Daniele, Brito, Ana, Brogi, Matteo, Brown, Beverly, Brown, David J. A., Brun, Allan Sacha, Bruno, Giovanni, Bruns, Michael, Buchhave, Lars A., Bugnet, Lisa, Buldgen, Gaël, Burgess, Patrick, Busatta, Andrea, Busso, Giorgia, Buzasi, Derek, Caballero, José A., Cabral, Alexandre, Gomez, Juan-Francisco Cabrero, Calderone, Flavia, Cameron, Robert, Cameron, Andrew, Campante, Tiago, Gestal, Néstor Campos, Martins, Bruno Leonardo Canto, Cara, Christophe, Carone, Ludmila, Carrasco, Josep Manel, Casagrande, Luca, Casewell, Sarah L., Cassisi, Santi, Castellani, Marco, Castro, Matthieu, Catala, Claude, Fernández, Irene Catalán, Catelan, Márcio, Cegla, Heather, Cerruti, Chiara, Cessa, Virginie, Chadid, Merieme, Chaplin, William, Charpinet, Stephane, Chiappini, Cristina, Chiarucci, Simone, Chiavassa, Andrea, Chinellato, Simonetta, Chirulli, Giovanni, Christensen-Dalsgaard, Jørgen, Church, Ross, Claret, Antonio, Clarke, Cathie, Claudi, Riccardo, Clermont, Lionel, Coelho, Hugo, Coelho, Joao, Cogato, Fabrizio, Colomé, Josep, Condamin, Mathieu, García, Fernando Conde, Conseil, Simon, Corbard, Thierry, Correia, Alexandre C. M., Corsaro, Enrico, Cosentino, Rosario, Costes, Jean, Cottinelli, Andrea, Covone, Giovanni, Creevey, Orlagh L., Crida, Aurelien, Csizmadia, Szilard, Cunha, Margarida, Curry, Patrick, da Costa, Jefferson, da Silva, Francys, Dalal, Shweta, Damasso, Mario, Damiani, Cilia, Damiani, Francesco, Chagas, Maria Liduina das, Davies, Melvyn, Davies, Guy, Davies, Ben, Davison, Gary, de Almeida, Leandro, de Angeli, Francesca, de Barros, Susana Cristina Cabral, Leão, Izan de Castro, de Freitas, Daniel Brito, de Freitas, Marcia Cristina, De Martino, Domitilla, de Medeiros, José Renan, de Paula, Luiz Alberto, Gómez, Álvaro de Pedraza, de Plaa, Jelle, De Ridder, Joris, Deal, Morgan, Decin, Leen, Deeg, Hans, Innocenti, Scilla Degl, Deheuvels, Sebastien, del Burgo, Carlos, Del Sordo, Fabio, Delgado-Mena, Elisa, Demangeon, Olivier, Denk, Tilmann, Derekas, Aliz, Desert, Jean-Michel, Desidera, Silvano, Dexet, Marc, Di Criscienzo, Marcella, Di Giorgio, Anna Maria, Di Mauro, Maria Pia, Rial, Federico Jose Diaz, Díaz-García, José-Javier, Dima, Marco, Dinuzzi, Giacomo, Dionatos, Odysseas, Distefano, Elisa, Nascimento Jr., Jose-Dias do, Domingo, Albert, D'Orazi, Valentina, Dorn, Caroline, Doyle, Lauren, Duarte, Elena, Ducellier, Florent, Dumaye, Luc, Dumusque, Xavier, Dupret, Marc-Antoine, Eggenberger, Patrick, Ehrenreich, David, Eigmüller, Philipp, Eising, Johannes, Emilio, Marcelo, Eriksson, Kjell, Ermocida, Marco, Giribaldi, Riano Isidoro Escate, Eschen, Yoshi, ez, Lucía Espinosa Yá, Estrela, In s, Evans, Dafydd Wyn, Fabbian, Damian, Fabrizio, Michele, Faria, João Pedro, Farina, Maria, Farinato, Jacopo, Feliz, Dax, Feltzing, Sofia, Fenouillet, Thomas, Fernández, Miguel, Ferrari, Lorenza, Ferraz-Mello, Sylvio, Fialho, Fabio, Fienga, Agnes, Figueira, Pedro, Fiori, Laura, Flaccomio, Ettore, Focardi, Mauro, Foley, Steve, Fontignie, Jean, Ford, Dominic, Fornazier, Karin, Forveille, Thierry, Fossati, Luca, Franca, Rodrigo de Marca, da Silva, Lucas Franco, Frasca, Antonio, Fridlund, Malcolm, Furlan, Marco, Gabler, Sarah-Maria, Gaido, Marco, Gallagher, Andrew, Sempere, Paloma I. Gallego, Galli, Emanuele, García, Rafael A., Hernández, Antonio García, Munoz, Antonio Garcia, García-Vázquez, Hugo, Haba, Rafael Garrido, Gaulme, Patrick, Gauthier, Nicolas, Gehan, Charlotte, Gent, Matthew, Georgieva, Iskra, Ghigo, Mauro, Giana, Edoardo, Gill, Samuel, Girardi, Leo, Winter, Silvia Giuliatti, Giusi, Giovanni, da Silva, João Gomes, Zazo, Luis Jorge Gómez, Gomez-Lopez, Juan Manuel, Hernández, Jonay Isai González, Murillo, Kevin Gonzalez, Melchor, Alejandro Gonzalo, Gorius, Nicolas, Gouel, Pierre-Vincent, Goulty, Duncan, Granata, Valentina, Grenfell, John Lee, bach, Denis Grie, Grolleau, Emmanuel, Grouffal, Salomé, Grziwa, Sascha, Guarcello, Mario Giuseppe, Gueguen, Lo c, Guenther, Eike Wolf, Guilhem, Terrasa, Guillerot, Lucas, Guillot, Tristan, Guiot, Pierre, Guterman, Pascal, Gutiérrez, Antonio, Gutiérrez-Canales, Fernando, Hagelberg, Janis, Haldemann, Jonas, Hall, Cassandra, Handberg, Rasmus, Harrison, Ian, Harrison, Diana L., Hasiba, Johann, Haswell, Carole A., Hatalova, Petra, Hatzes, Artie, Haywood, Raphaelle, Hébrard, Guillaume, Heckes, Frank, Heiter, Ulrike, Hekker, Saskia, Heller, René, Helling, Christiane, Helminiak, Krzysztof, Hemsley, Simon, Heng, Kevin, Herbst, Konstantin, Hermans, Aline, Hermes, JJ, Torres, Nadia Hidalgo, Hinkel, Natalie, Hobbs, David, Hodgkin, Simon, Hofmann, Karl, Hojjatpanah, Saeed, Houdek, Günter, Huber, Daniel, Huesler, Joseph, Hui-Bon-Hoa, Alain, Huygen, Rik, Huynh, Duc-Dat, Iro, Nicolas, Irwin, Jonathan, Irwin, Mike, Izidoro, André, Jacquinod, Sophie, Jannsen, Nicholas Emborg, Janson, Markus, Jeszenszky, Harald, Jiang, Chen, Mancebo, Antonio José Jimenez, Jofre, Paula, Johansen, Anders, Johnston, Cole, Jones, Geraint, Kallinger, Thomas, Kálmán, Szilárd, Kanitz, Thomas, Karjalainen, Marie, Karjalainen, Raine, Karoff, Christoffer, Kawaler, Steven, Kawata, Daisuke, Keereman, Arnoud, Keiderling, David, Kennedy, Tom, Kenworthy, Matthew, Kerschbaum, Franz, Kidger, Mark, Kiefer, Flavien, Kintziger, Christian, Kislyakova, Kristina, Kiss, László, Klagyivik, Peter, Klahr, Hubert, Klevas, Jonas, Kochukhov, Oleg, Köhler, Ulrich, Kolb, Ulrich, Koncz, Alexander, Korth, Judith, Kostogryz, Nadiia, Kovács, Gábor, Kovács, József, Kozhura, Oleg, Krivova, Natalie, Kucinskas, Arunas, Kuhlemann, Ilyas, Kupka, Friedrich, Laauwen, Wouter, Labiano, Alvaro, Lagarde, Nadege, Laget, Philippe, Laky, Gunter, Lam, Kristine Wai Fun, Lambrechts, Michiel, Lammer, Helmut, Lanza, Antonino Francesco, Lanzafame, Alessandro, Martiz, Mariel Lares, Laskar, Jacques, Latter, Henrik, Lavanant, Tony, Lawrenson, Alastair, Lazzoni, Cecilia, Lebre, Agnes, Lebreton, Yveline, Etangs, Alain Lecavelier des, Lee, Katherine, Leinhardt, Zoe, Leleu, Adrien, Lendl, Monika, Leto, Giuseppe, Levillain, Yves, Libert, Anne-Sophie, Lichtenberg, Tim, Ligi, Roxanne, Lignieres, Francois, Lillo-Box, Jorge, Linsky, Jeffrey, Liu, John Scige, Loidolt, Dominik, Longval, Yuying, Lopes, Ilídio, Lorenzani, Andrea, Ludwig, Hans-Guenter, Lund, Mikkel, Lundkvist, Mia Sloth, Luri, Xavier, Maceroni, Carla, Madden, Sean, Madhusudhan, Nikku, Maggio, Antonio, Magliano, Christian, Magrin, Demetrio, Mahy, Laurent, Maibaum, Olaf, Malac-Allain, LeeRoy, Malapert, Jean-Christophe, Malavolta, Luca, Maldonado, Jesus, Mamonova, Elena, Manchon, Louis, Manjón, Andres, Mann, Andrew, Mantovan, Giacomo, Marafatto, Luca, Marconi, Marcella, Mardling, Rosemary, Marigo, Paola, Marinoni, Silvia, Marques, rico, Marques, Joao Pedro, Marrese, Paola Maria, Marshall, Douglas, Perales, Silvia Martínez, Mary, David, Marzari, Francesco, Masana, Eduard, Mascher, Andrina, Mathis, Stéphane, Mathur, Savita, Vodopivec, Iris Martín, Figueiredo, Ana Carolina Mattiuci, Maxted, Pierre F. L., Mazeh, Tsevi, Mazevet, Stephane, Mazzei, Francesco, McCormac, James, McMillan, Paul, Menou, Lucas, Merle, Thibault, Meru, Farzana, Mesa, Dino, Messina, Sergio, Mészáros, Szabolcs, Meunier, Nadége, Meunier, Jean-Charles, Micela, Giuseppina, Michaelis, Harald, Michel, Eric, Michielsen, Mathias, Michtchenko, Tatiana, Miglio, Andrea, Miguel, Yamila, Milligan, David, Mirouh, Giovanni, Mitchell, Morgan, Moedas, Nuno, Molendini, Francesca, Molnár, László, Mombarg, Joey, Montalban, Josefina, Montalto, Marco, Monteiro, Mário J. P. F. G., Sánchez, Francisco Montoro, Morales, Juan Carlos, Morales-Calderon, Maria, Morbidelli, Alessandro, Mordasini, Christoph, Moreau, Chrystel, Morel, Thierry, Morello, Guiseppe, Morin, Julien, Mortier, Annelies, Mosser, Beno t, Mourard, Denis, Mousis, Olivier, Moutou, Claire, Mowlavi, Nami, Moya, Andrés, Muehlmann, Prisca, Muirhead, Philip, Munari, Matteo, Musella, Ilaria, Mustill, Alexander James, Nardetto, Nicolas, Nardiello, Domenico, Narita, Norio, Nascimbeni, Valerio, Nash, Anna, Neiner, Coralie, Nelson, Richard P., Nettelmann, Nadine, Nicolini, Gianalfredo, Nielsen, Martin, Niemi, Sami-Matias, Noack, Lena, Noels-Grotsch, Arlette, Noll, Anthony, Norazman, Azib, Norton, Andrew J., Nsamba, Benard, Ofir, Aviv, Ogilvie, Gordon, Olander, Terese, Olivetto, Christian, Olofsson, Göran, Ong, Joel, Ortolani, Sergio, Oshagh, Mahmoudreza, Ottacher, Harald, Ottensamer, Roland, Ouazzani, Rhita-Maria, Paardekooper, Sijme-Jan, Pace, Emanuele, Pajas, Miriam, Palacios, Ana, Palandri, Gaelle, Palle, Enric, Paproth, Carsten, Parro, Vanderlei, Parviainen, Hannu, Granado, Javier Pascual, Passegger, Vera Maria, Pastor-Morales, Carmen, Pätzold, Martin, Pedersen, May Gade, Hidalgo, David Pena, Pepe, Francesco, Pereira, Filipe, Persson, Carina M., Pertenais, Martin, Peter, Gisbert, Petit, Antoine C., Petit, Pascal, Pezzuto, Stefania, Pichierri, Gabriele, Pietrinferni, Adriano, Pinheiro, Fernando, Pinsonneault, Marc, Plachy, Emese, Plasson, Philippe, Plez, Bertrand, Poppenhaeger, Katja, Poretti, Ennio, Portaluri, Elisa, Portell, Jordi, de Mello, Gustavo Frederico Porto, Poyatos, Julien, Pozuelos, Francisco J., Moroni, Pier Giorgio Prada, Pricopi, Dumitru, Prisinzano, Loredana, Quade, Matthias, Quirrenbach, Andreas, Reina, Julio Arturo Rabanal, Soares, Maria Cristina Rabello, Raimondo, Gabriella, Rainer, Monica, Rodón, Jose Ramón, Ramón-Ballesta, Alejandro, Zapata, Gonzalo Ramos, Rätz, Stefanie, Rauterberg, Christoph, Redman, Bob, Redmer, Ronald, Reese, Daniel, Regibo, Sara, Reiners, Ansgar, Reinhold, Timo, Renie, Christian, Ribas, Ignasi, Ribeiro, Sergio, Ricciardi, Thiago Pereira, Rice, Ken, Richard, Olivier, Riello, Marco, Rieutord, Michel, Ripepi, Vincenzo, Rixon, Guy, Rockstein, Steve, Ortiz, José Ramón Rodón, Rodríguez, María Teresa Rodrigo, Amor, Alberto Rodríguez, Díaz, Luisa Fernanda Rodríguez, Garcia, Juan Pablo Rodriguez, Rodriguez-Gomez, Julio, Roehlly, Yannick, Roig, Fernando, Rojas-Ayala, Bárbara, Rolf, Tobias, Rørsted, Jakob Lysgaard, Rosado, Hugo, Rosotti, Giovanni, Roth, Olivier, Roth, Markus, Rousseau, Alex, Roxburgh, Ian, Roy, Fabrice, Royer, Pierre, Ruane, Kirk, Mastropasqua, Sergio Rufini, de Galarreta, Claudia Ruiz, Russi, Andrea, Saar, Steven, Saillenfest, Melaine, Salaris, Maurizio, Salmon, Sebastien, Saltas, Ippocratis, Samadi, Réza, Samadi, Aunia, Samra, Dominic, da Silva, Tiago Sanches, Carrasco, Miguel Andrés Sánchez, Santerne, Alexandre, Pé, Amaia Santiago, Santoli, Francesco, Santos, ngela R. G., Mesa, Rosario Sanz, Sarro, Luis Manuel, Scandariato, Gaetano, Schäfer, Martin, Schlafly, Edward, Schmider, François-Xavier, Schneider, Jean, Schou, Jesper, Schunker, Hannah, Schwarzkopf, Gabriel Jörg, Serenelli, Aldo, Seynaeve, Dries, Shan, Yutong, Shapiro, Alexander, Shipman, Russel, Sicilia, Daniela, sanmartin, Maria Angeles Sierra, Sigot, Axelle, Silliman, Kyle, Silvotti, Roberto, Simon, Attila E., Napoli, Ricardo Simoyama, Skarka, Marek, Smalley, Barry, Smiljanic, Rodolfo, Smit, Samuel, Smith, Alexis, Smith, Leigh, Snellen, Ignas, Sódor, Ádám, Sohl, Frank, Solanki, Sami K., Sortino, Francesca, Sousa, Sérgio, Southworth, John, Souto, Diogo, Sozzetti, Alessandro, Stamatellos, Dimitris, Stassun, Keivan, Steller, Manfred, Stello, Dennis, Stelzer, Beate, Stiebeler, Ulrike, Stokholm, Amalie, Storelvmo, Trude, Strassmeier, Klaus, Strøm, Paul Anthony, Strugarek, Antoine, Sulis, Sophia, vanda, Michal, Szabados, László, Szabó, Róbert, Szabó, Gyula M., Szuszkiewicz, Ewa, Talens, Geert Jan, Teti, Daniele, Theisen, Tom, Thévenin, Frédéric, Thoul, Anne, Tiphene, Didier, Titz-Weider, Ruth, Tkachenko, Andrew, Tomecki, Daniel, Tonfat, Jorge, Tosi, Nicola, Trampedach, Regner, Traven, Gregor, Triaud, Amaury, Trønnes, Reidar, Tsantaki, Maria, Tschentscher, Matthias, Turin, Arnaud, Tvaruzka, Adam, Ulmer, Bernd, Ulmer-Moll, Solène, Ulusoy, Ceren, Umbriaco, Gabriele, Valencia, Diana, Valentini, Marica, Valio, Adriana, Guijarro, Ángel Luis Valverde, Van Eylen, Vincent, Van Grootel, Valerie, van Kempen, Tim A., Van Reeth, Timothy, Van Zelst, Iris, Vandenbussche, Bart, Vasiliou, Konstantinos, Vasilyev, Valeriy, de Mascarenhas, David Vaz, Vazan, Allona, Nunez, Marina Vela, Velloso, Eduardo Nunes, Ventura, Rita, Ventura, Paolo, Venturini, Julia, Trallero, Isabel Vera, Veras, Dimitri, Verdugo, Eva, Verma, Kuldeep, Vibert, Didier, Martinez, Tobias Vicanek, Vida, Krisztián, Vigan, Arthur, Villacorta, Antonio, Villaver, Eva, Aparicio, Marcos Villaverde, Viotto, Valentina, Vorobyov, Eduard, Vorontsov, Sergey, Wagner, Frank W., Walloschek, Thomas, Walton, Nicholas, Walton, Dave, Wang, Haiyang, Waters, Rens, Watson, Christopher, Wedemeyer, Sven, Weeks, Angharad, Weingrill, Jörg, Weiss, Annita, Wendler, Belinda, West, Richard, Westerdorff, Karsten, Westphal, Pierre-Amaury, Wheatley, Peter, White, Tim, Whittaker, Amadou, Wickhusen, Kai, Wilson, Thomas, Windsor, James, Winter, Othon, Winther, Mark Lykke, Winton, Alistair, Witteck, Ulrike, Witzke, Veronika, Woitke, Peter, Wolter, David, Wuchterl, Günther, Wyatt, Mark, Yang, Dan, Yu, Jie, Sanchez, Ricardo Zanmar, Osorio, María Rosa Zapatero, Zechmeister, Mathias, Zhou, Yixiao, Ziemke, Claas, and Zwintz, Konstanze

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

PLATO (PLAnetary Transits and Oscillations of stars) is ESA's M3 mission designed to detect and characterise extrasolar planets and perform asteroseismic monitoring of a large number of stars. PLATO will detect small planets (down to <2 R_(Earth)) around bright stars (<11 mag), including terrestrial planets in the habitable zone of solar-like stars. With the complement of radial velocity observations from the ground, planets will be characterised for their radius, mass, and age with high accuracy (5 %, 10 %, 10 % for an Earth-Sun combination respectively). PLATO will provide us with a large-scale catalogue of well-characterised small planets up to intermediate orbital periods, relevant for a meaningful comparison to planet formation theories and to better understand planet evolution. It will make possible comparative exoplanetology to place our Solar System planets in a broader context. In parallel, PLATO will study (host) stars using asteroseismology, allowing us to determine the stellar properties with high accuracy, substantially enhancing our knowledge of stellar structure and evolution. The payload instrument consists of 26 cameras with 12cm aperture each. For at least four years, the mission will perform high-precision photometric measurements. Here we review the science objectives, present PLATO's target samples and fields, provide an overview of expected core science performance as well as a description of the instrument and the mission profile at the beginning of the serial production of the flight cameras. PLATO is scheduled for a launch date end 2026. This overview therefore provides a summary of the mission to the community in preparation of the upcoming operational phases.

Published
2024

4. Fundamental Physics with ESPRESSO, Constraining a simple parametrisation for varying $\alpha$

Author

da Fonseca, Vitor, Barreiro, Tiago, Nunes, Nelson J., Cristiani, Stefano, Cupani, Guido, D'Odorico, Valentina, Santos, Ricardo Génova, Leite, Ana C. O., Marques, Catarina M. J., Martins, Carlos J. A. P., Milaković, Dinko, Molaro, Paolo, Murphy, Michael T., Schmidt, Tobias M., Abreu, Manuel, Adibekyan, Vardan, Cabral, Alexandre, Di Marcantonio, Paolo, Hernández, Jonay I. González, Palle, Enric, Pepe, Francesco A., Rebolo, Rafael, Santos, Nuno C., Sousa, Sérgio G., Sozzetti, Alessandro, Mascareño, Alejandro Suárez, and Osorio, Maria-Rosa Zapatero

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The spectrograph ESPRESSO recently obtained a limit on the variation of the fine-structure constant, $\alpha$, through measurements along the line of sight of a bright quasar with a precision of $1.36$ ppm at $1\sigma$ level. This imposes new constraints on cosmological models with a varying $\alpha$. We assume such a model where the electromagnetic sector is coupled to a scalar field dark energy responsible for the current acceleration of the Universe. We parametrise the variation of $\alpha$ with two extra parameters, one defining the cosmological evolution of the quintessence component and the other fixing the coupling with the electromagnetic field. The objective of this work is to constrain these parameters with both astrophysical and local probes. We also carried out a comparative analysis of how each data probe may constrain our parametrisation. We performed a Bayesian analysis by comparing the predictions of the model with observations. The astrophysical datasets are composed of quasar spectra measurements, including the latest ESPRESSO data point, as well as Planck observations of the cosmic microwave background. We combined these with local results from atomic clocks and the MICROSCOPE experiment. The constraints placed on the quintessence parameter are consistent with a null variation of the field, and are therefore compatible with a $\Lambda$CDM cosmology. The constraints on the coupling to the electromagnetic sector are dominated by the E\"otv\"os parameter local bound. More precise measurements with ESPRESSO will be extremely important to study the cosmological evolution of $\alpha$ as it probes an interval of redshift not accessible to other types of observations. However, for this particular model, current available data favour a null variation of $\alpha$ resulting mostly from the strong MICROSCOPE limits., Comment: 9 pages, 7 figures, as published in A&A

Published
2022
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6. Fundamental physics with ESPRESSO: Precise limit on variations in the fine-structure constant towards the bright quasar HE 0515$-$4414

Author

Murphy, Michael T., Molaro, Paolo, Leite, Ana C. O., Cupani, Guido, Cristiani, Stefano, D'Odorico, Valentina, Santos, Ricardo Génova, Martins, Carlos J. A. P., Milaković, Dinko, Nunes, Nelson J., Schmidt, Tobias M., Pepe, Francesco A., Rebolo, Rafael, Santos, Nuno C., Sousa, Sérgio G., Osorio, Maria-Rosa Zapatero, Amate, Manuel, Adibekyan, Vardan, Alibert, Yann, Prieto, Carlos Allende, Baldini, Veronica, Benz, Willy, Bouchy, François, Cabral, Alexandre, Dekker, Hans, Di Marcantonio, Paolo, Ehrenreich, David, Figueira, Pedro, Hernández, Jonay I. González, Landoni, Marco, Lovis, Christophe, Curto, Gaspare Lo, Manescau, Antonio, Mégevand, Denis, Mehner, Andrea, Micela, Giuseppina, Pasquini, Luca, Poretti, Ennio, Riva, Marco, Sozzetti, Alessandro, Mascareño, Alejandro Suárez, Udry, Stéphane, and Zerbi, Filippo

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The strong intervening absorption system at redshift 1.15 towards the very bright quasar HE 0515$-$4414 is the most studied absorber for measuring possible cosmological variations in the fine-structure constant, $\alpha$. We observed HE 0515$-$4414 for 16.1$\,$h with the Very Large Telescope and present here the first constraint on relative variations in $\alpha$ with parts-per-million (ppm) precision from the new ESPRESSO spectrograph: $\Delta\alpha/\alpha = 1.3 \pm 1.3_{\rm stat} \pm 0.4_{\rm sys}\,{\rm ppm}$. The statistical uncertainty (1$\sigma$) is similar to the ensemble precision of previous large samples of absorbers, and derives from the high S/N achieved ($\approx$105 per 0.4$\,$km$\,$s$^{-1}$ pixel). ESPRESSO's design, and calibration of our observations with its laser frequency comb, effectively removed wavelength calibration errors from our measurement. The high resolving power of our ESPRESSO spectrum ($R=145000$) enabled the identification of very narrow components within the absorption profile, allowing a more robust analysis of $\Delta\alpha/\alpha$. The evidence for the narrow components is corroborated by their correspondence with previously detected molecular hydrogen and neutral carbon. The main remaining systematic errors arise from ambiguities in the absorption profile modelling, effects from redispersing the individual quasar exposures, and convergence of the parameter estimation algorithm. All analyses of the spectrum, including systematic error estimates, were initially blinded to avoid human biases. We make our reduced ESPRESSO spectrum of HE 0515$-$4414 publicly available for further analysis. Combining our ESPRESSO result with 28 measurements, from other spectrographs, in which wavelength calibration errors have been mitigated, yields a weighted mean $\Delta\alpha/\alpha = -0.5 \pm 0.5_{\rm stat} \pm 0.4_{\rm sys}\,$ppm at redshifts 0.6-2.4., Comment: Accepted by A&A. The ESPRESSO quasar spectrum, reduced contributing exposures, and absorption profile fits are available at https://github.com/MTMurphy77/ESPRESSO_HE0515-4414

Published
2021
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8. Fundamental physics with Espresso: Towards an accurate wavelength calibration for a precision test of the fine-structure constant

Author

Schmidt, Tobias M., Molaro, Paolo, Murphy, Michael T., Lovis, Christophe, Cupani, Guido, Cristiani, Stefano, Pepe, Francesco A., Rebolo, Rafael, Santos, Nuno C., Abreu, Manuel, Adibekyan, Vardan, Alibert, Yann, Aliverti, Matteo, Allart, Romain, Prieto, Carlos Allende, Alves, David, Baldini, Veronica, Broeg, Christopher, Cabral, Alexandre, Calderone, Giorgio, Cirami, Roberto, Coelho, João, Coretti, Igor, D'Odorico, Valentina, Di Marcantonio, Paolo, Ehrenreich, David, Figueira, Pedro, Genoni, Matteo, Santos, Ricardo Génova, Hernández, Jonay I. González, Kerber, Florian, Landoni, Marco, Leite, Ana C. O., Lizon, Jean-Louis, Curto, Gaspare Lo, Manescau, Antonio, Martins, Carlos J. A. P., Megévand, Denis, Mehner, Andrea, Micela, Giuseppina, Modigliani, Andrea, Monteiro, Manuel, Monteiro, Mario J. P. F. G., Mueller, Eric, Nunes, Nelson J., Oggioni, Luca, Oliveira, António, Pariani, Giorgio, Pasquini, Luca, Redaelli, Edoardo, Riva, Marco, Santos, Pedro, Sosnowska, Danuta, Sousa, Sérgio G., Sozzetti, Alessandro, Mascareño, Alejandro Suárez, Udry, Stéphane, Osorio, Maria-Rosa Zapatero, and Zerbi, Filippo

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Astrophysics of Galaxies
Abstract

Observations of metal absorption systems in the spectra of distant quasars allow to constrain a possible variation of the fine-structure constant throughout the history of the Universe. Such a test poses utmost demands on the wavelength accuracy and previous studies were limited by systematics in the spectrograph wavelength calibration. A substantial advance in the field is therefore expected from the new ultra-stable high-resolution spectrograph Espresso, recently installed at the VLT. In preparation of the fundamental physics related part of the Espresso GTO program, we present a thorough assessment of the Espresso wavelength accuracy and identify possible systematics at each of the different steps involved in the wavelength calibration process. Most importantly, we compare the default wavelength solution, based on the combination of Thorium-Argon arc lamp spectra and a Fabry-P\'erot interferometer, to the fully independent calibration obtained from a laser frequency comb. We find wavelength-dependent discrepancies of up to 24m/s. This substantially exceeds the photon noise and highlights the presence of different sources of systematics, which we characterize in detail as part of this study. Nevertheless, our study demonstrates the outstanding accuracy of Espresso with respect to previously used spectrographs and we show that constraints of a relative change of the fine-structure constant at the $10^{-6}$ level can be obtained with Espresso without being limited by wavelength calibration systematics., Comment: 27 pages, accepted for publication in A&A

Published
2020
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9. HIRES, the high-resolution spectrograph for the ELT

Author

Marconi, Alessandro, Abreu, Manuel, Adibekyan, Vardan, Aliverti, Matteo, Prieto, Carlos Allende, Amado, Pedro J., Amate, Manuel, Artigau, Etienne, Augusto, Sergio R., Barros, Susana, Becerril, Santiago, Benneke, Bjorn, Bergin, Edwin, Berio, Philippe, Bezawada, Naidu, Boisse, Isabelle, Bonfils, Xavier, Bouchy, Francois, Broeg, Christopher, Cabral, Alexandre, Calvo-Ortega, Rocio, Martins, Bruno Leonardo Canto, Chazelas, Bruno, Chiavassa, Andrea, Christensen, Lise B., Cirami, Roberto, Coretti, Igor, Cristiani, Stefano, Parro, Vanderlei Cunha, Cupani, Guido, Leao, Izan de Castro, de Medeiros, Jose Renan, de Souza, Marco Antonio Furlan, Di Marcantonio, Paolo, Di Varano, Igor, D'Odorico, Valentina, Doyon, Rene, Drass, Holger, Figueira, Pedro, Fragoso, Ana Belen, Fynbo, Johan Peter Uldall, Gallo, Elena, Genoni, Matteo, Hernandez, Jonay I. Gonzalez, Haehnelt, Martin, Larrondo, Julie Hlavacek, Hughes, Ian, Huke, Philipp, Humphrey, Andrew, Kjeldsen, Hans, Korn, Andreas, Kouach, Driss, Landoni, Marco, Liske, Jochen, Lovis, Christophe, Lunney, David, Maiolino, Roberto, Malo, Lison, Marquart, Thomas, Martins, Carlos J. A. P., Mason, Elena, Monnier, John, Monteiro, Manuel A., Mordasini, Christoph, Morris, Tim, Murray, Graham J., Niedzielski, Andrzej, Nunes, Nelson, Oliva, Ernesto, Origlia, Livia, Palle, Enric, Pariani, Giorgio, Parr-Burman, Phil, Penate, Jose, Pepe, Francesco, Pinna, Enrico, Piskunov, Nikolai, Rasilla, Jose Luis, Rees, Phil, Rebolo, Rafael, Reiners, Ansgar, Riva, Marco, Rousseau, Sylvain, Sanna, Nicoletta, Santos, Nuno C., Sarajlic, Mirsad, Shen, Tzu-Chiang, Sortino, Francesca, Sosnowska, Danuta, Sousa, Sergio, Stempels, Eric, Strassmeier, Klaus G., Tenegi, Fabio, Tozzi, Andrea, Udry, Stephane, Valenziano, Luca, Vanzi, Leonardo, Weber, Michael, Woche, Manfred, Xompero, Marco, Zackrisson, Erik, and Osorio, Maria Rosa Zapatero

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

HIRES will be the high-resolution spectrograph of the European Extremely Large Telescope at optical and near-infrared wavelengths. It consists of three fibre-fed spectrographs providing a wavelength coverage of 0.4-1.8 mic (goal 0.35-1.8 mic) at a spectral resolution of ~100,000. The fibre-feeding allows HIRES to have several, interchangeable observing modes including a SCAO module and a small diffraction-limited IFU in the NIR. Therefore, it will be able to operate both in seeing and diffraction-limited modes. ELT-HIRES has 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 bio signatures from exoplanet atmospheres, finding the fingerprints of the first generation of stars (PopIII), 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., Comment: to appear in the ESO Messenger No.182, December 2020

Published
2020
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10. Nightside condensation of iron in an ultra-hot giant exoplanet

Author

Ehrenreich, David, Lovis, Christophe, Allart, Romain, Osorio, María Rosa Zapatero, Pepe, Francesco, Cristiani, Stefano, Rebolo, Rafael, Santos, Nuno C., Borsa, Francesco, Demangeon, Olivier, Dumusque, Xavier, Hernández, Jonay I. González, Casasayas-Barris, Núria, Ségransan, Damien, Sousa, Sérgio, Abreu, Manuel, Adibekyan, Vardan, Affolter, Michael, Prieto, Carlos Allende, Alibert, Yann, Aliverti, Matteo, Alves, David, Amate, Manuel, Avila, Gerardo, Baldini, Veronica, Bandy, Timothy, Benz, Willy, Bianco, Andrea, Bolmont, Émeline, Bouchy, François, Bourrier, Vincent, Broeg, Christopher, Cabral, Alexandre, Calderone, Giorgio, Pallé, Enric, Cegla, H. M., Cirami, Roberto, Coelho, João M. P., Conconi, Paolo, Coretti, Igor, Cumani, Claudio, Cupani, Guido, Dekker, Hans, Delabre, Bernard, Deiries, Sebastian, D'Odorico, Valentina, Di Marcantonio, Paolo, Figueira, Pedro, Fragoso, Ana, Genolet, Ludovic, Genoni, Matteo, Santos, Ricardo Génova, Hara, Nathan, Hughes, Ian, Iwert, Olaf, Kerber, Florian, Knudstrup, Jens, Landoni, Marco, Lavie, Baptiste, Lizon, Jean-Louis, Lendl, Monika, Curto, Gaspare Lo, Maire, Charles, Manescau, Antonio, Martins, C. J. A. P., Mégevand, Denis, Mehner, Andrea, Micela, Giusi, Modigliani, Andrea, Molaro, Paolo, Monteiro, Manuel, Monteiro, Mario, Moschetti, Manuele, Müller, Eric, Nunes, Nelson, Oggioni, Luca, Oliveira, António, Pariani, Giorgio, Pasquini, Luca, Poretti, Ennio, Rasilla, José Luis, Redaelli, Edoardo, Riva, Marco, Tschudi, Samuel Santana, Santin, Paolo, Santos, Pedro, Milla, Alex Segovia, Seidel, Julia V., Sosnowska, Danuta, Sozzetti, Alessandro, Spanò, Paolo, Mascareño, Alejandro Suárez, Tabernero, Hugo, Tenegi, Fabio, Udry, Stéphane, Zanutta, Alessio, and Zerbi, Filippo

Subjects
Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract

Ultra-hot giant exoplanets receive thousands of times Earth's insolation. Their high-temperature atmospheres (>2,000 K) are ideal laboratories for studying extreme planetary climates and chemistry. Daysides are predicted to be cloud-free, dominated by atomic species and substantially hotter than nightsides. Atoms are expected to recombine into molecules over the nightside, resulting in different day-night chemistry. While metallic elements and a large temperature contrast have been observed, no chemical gradient has been measured across the surface of such an exoplanet. Different atmospheric chemistry between the day-to-night ("evening") and night-to-day ("morning") terminators could, however, be revealed as an asymmetric absorption signature during transit. Here, we report the detection of an asymmetric atmospheric signature in the ultra-hot exoplanet WASP-76b. We spectrally and temporally resolve this signature thanks to the combination of high-dispersion spectroscopy with a large photon-collecting area. The absorption signal, attributed to neutral iron, is blueshifted by -11+/-0.7 km s-1 on the trailing limb, which can be explained by a combination of planetary rotation and wind blowing from the hot dayside. In contrast, no signal arises from the nightside close to the morning terminator, showing that atomic iron is not absorbing starlight there. Iron must thus condense during its journey across the nightside., Comment: Published in Nature (Accepted on 24 January 2020.) 33 pages, 11 figures, 3 tables

Published
2020
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11. The impact of atmospheric dispersion in the performance of high-resolution spectrographs

Author

Wehbe, Bachar, Cabral, Alexandre, Martins, Jorge, Figueira, Pedro, Santos, Nuno, and Ávila, Gerardo

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Differential atmospheric dispersion is a wavelength-dependent effect introduced by the atmosphere. It is one of the instrumental errors that can affect the position of the target as perceived on the sky and its flux distribution. This effect will affect the results of astronomical observations if not corrected by an atmospheric dispersion corrector (ADC). In high-resolution spectrographs, in order to reach a radial velocity (RV) precision of 10 cm/s, an ADC is expected to return residuals at only a few tens of milli-arcseconds (mas). In fact, current state-of-the-art spectrographs conservatively require this level of residuals, although no work has been done to quantify the impact of atmospheric dispersion. In this work we test the effect of atmospheric dispersion on astronomical observations in general, and in particular on RV precision degradation and flux losses. Our scientific objective was to quantify the amount of residuals needed to fulfill the requirements set on an ADC during the design phase. We found that up to a dispersion of 100 mas, the effect on the RV is negligible. However, on the flux losses, such a dispersion can create a loss of ~2% at 380 nm, a significant value when efficiency is critical. The requirements set on ADC residuals should take into consideration the atmospheric conditions where the ADC will function, and also all the aspects related with not only the RV precision requirements but also the guiding camera used, the tolerances on the flux loss, and the different melt data of the chosen glasses., Comment: accepted for publications in MNRAS

Published
2019
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12. Spatial coherence characterization of light: an experimental study using digital micromirror devices

Author

Magalhães, Tiago E. C., Rebordão, José M., and Cabral, Alexandre

Subjects
Physics - Instrumentation and Detectors, Physics - Optics, 78A45, 78-05
Abstract

We present spatial coherence measurements of partially coherent light in the far-field of incoherent sources with an experimental setup based on the Thompson-Wolf and Partanen-Turunen-Tervo experiments, to be performed in the context of a possible solar coherence measurement space instrument. The optical setup consists of a telescope to collimate light from a source, to diffract it by a digital micromirror device implementing a Young double-aperture interferometer in retroreflection mode, and finally to image the source into a two-dimensional sensor. Two multimode optical fibers with different diameters were used as incoherent sources and the results obtained for the spectral degree of coherence are compared to those expected from the van Cittert-Zernike theorem., Comment: Preprint submitted to Elsevier, 7 pages, 5 figures

Published
2019
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13. The development of an optical design tool for atmospheric dispersion correction

Author

Wehbe, Bachar, Cabral, Alexandre, and Avila, Gerardo

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

In ground based astronomical observations, atmospheric dispersion shifts the image of the object at different wavelengths due to the wavelength-dependent index of refraction of the atmosphere. Thus, using an Atmospheric Dispersion Corrector (ADC) is mandatory in order to avoid any wavelength dependent losses. Typical ADC configurations, for high resolution astronomical instruments, are two counter-rotating prisms, a set of, at least, four prisms paired together. With the arrival of large telescopes with higher angular magnification, and spectrographs with higher resolution, the requirements on the dispersion correction are becoming more critical due to the impact on the produced science (e.g. radial velocity precision). We developed an ADC optical design tool in order to select the best set of glasses in terms of residuals, transmission, resulting image quality, Fresnel losses, taking into account the required spectral range and typical atmospheric conditions where the ADC will be working. A demonstration of the capabilities of the tool is presented with the analysis of the impact of different melt data, the effect of different glass Sellmeier coefficients between catalog and measured ones, that can create a difference in the residuals above few tens of milli-arcseconds (mas). The tool allows the investigation of critical steps on the ADC design phase and speeds up the glass selection process critical for the harder requirements of the future instruments/telescopes.

Published
2019
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14. Atmospheric dispersion correction: model requirements and impact on radial velocity measurements

Author

Wehbe, Bachar, Cabral, Alexandre, Figueira, Pedro, and Avila, Gerardo

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

Observations with ground-based telescopes are affected by differential atmospheric dispersion when seen at a zenith angle different from zero, a consequence of the wavelength-dependent index of refraction of the atmosphere. One of the pioneering technology in detecting exoplanets is the technique of radial velocity (RV), that can be affected by uncorrected atmospheric dispersion. The current highest precision spectrographs are expected to deliver a precision of 10 cm/s (e.g., ESPRESSO). To minimize the atmospheric dispersion effect, an Atmospheric Dispersion Corrector (ADC) can be employed. ADC designs are based on sky dispersion models that nonetheless give different results; these can reach a few tens of milli-arcseconds (mas) in the sky (a difference up to 40 mas); a value close to the current requirements (20 mas in the case of ESPRESSO). In this paper we describe tests done with ESPRESSO and HARPS to understand the influence of atmospheric dispersion and its correction on RV precision. We also present a comparison of different sky models, using EFOSC2 data (between 600nm and 700nm), that will be used to improve on the design of ADCs.

Published
2019
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15. Morphological Characteristics of an Open Shelf Ridge at Rio Grande do Norte Continental Shelf, NE Brazil.

Author

Cabral, Alexandre P. and Noernberg, Mauricio A.

Subjects
*CONTINENTAL shelf, *TIDAL currents, *CORALLINE algae, *CORAL reefs & islands, *REMOTE-sensing images, *SAND dunes
Abstract

Cabral, A.P. and Noernberg, M.A., 2024. Morphological characteristics of an open shelf ridge at Rio Grande do Norte continental shelf, NE Brazil. Journal of Coastal Research, 40(6), 1166–1181. Charlotte (North Carolina), ISSN 0749-0208. This paper describes for the first time the occurrence of an open shelf ridge (OSR) in the South Atlantic Ocean, evidencing morphological differences with respect to occurrences in other regions. The unique configuration of this OSR derives from the characteristics of the shallow continental shelf frontal to the Calcanhar Cape, Rio Grande do Norte State, Brazil, where it is located. It is a shallow, narrow, stepped shelf with an escarpment corresponding to a drowned shoreline around the 35 m isobath. There are extensive siliciclastic and carbonate sand deposits, sand ribbons, subaqueous dune fields, coral reefs, and calcareous algae patches. The high transparency of the water allows the use of multitemporal optical satellite images from remote sensors in the bathymetric modeling and morphodynamic description, in conjunction with echo sounder surveys, in situ sampling, and modeling. The metocean conditions of the region were determined from current and wind data obtained in situ, as well as data from the Hybrid Coordinate Ocean Model (HYCOM) and Regional Ocean Modeling System (ROMS) numerical models. Combining these data allowed the identification, characterization, and analysis of the metocean patterns over the OSR. Superimposed onto the OSR, there is a field of asymmetric subaqueous dunes transverse to the ridge axis with wavelengths between 150 m and 2 km and heights between 2.5 m and 9 m, with a tendency for sediment transport offshore northwestward of the OSR crest. The synergistic effect of the dominant NE winds and the North Brazil Current with tidal currents drives the main metocean forcings. The hydrodynamic pattern for the main sedimentary deposit areas is described, and the effect of the OSR on general subaqueous dune field configuration is presented. [ABSTRACT FROM AUTHOR]

Published
2024
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19. Cryogenic testing of the integrated Ariel space telescope: design of the optical test equipment

Author

Coyle, Laura E., Matsuura, Shuji, Perrin, Marshall D., Spry, Robert, Abreu, Manuel, Nowicki, Keith, Bowles, Neil, Rashman, Maisie, Pereira, Cédric, Hutchinson, Jake, Alves, David Miguel Ventura de Castro, Evans, Rory, Watkins, Robert, Mir, Waqas, Walker, John-Paul, Argyriou, Ioannis, Guy, Joss, Schmoll, Juergen, Davison, Chris, Eshbaugh, Henry, Cabral, Alexandre, Drummond, Rachel, Desjonqueres, Lucile, Anderson, Mark, Bishop, Georgia, Eccleston, Paul, Pascale, Enzo, Caldwell, Andrew, and Tinetti, Giovanna

Published
2024
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23. NIRPS first light and early science: breaking the 1 m/s RV precision barrier at infrared wavelengths

Author

Bryant, Julia J., Motohara, Kentaro, Vernet, Joël R. D., Artigau, Étienne, Bouchy, François, Doyon, René, Baron, Frédérique, Malo, Lison, Wildi, François, Pepe, Franceso, Cook, Neil J., Thibault, Simon, Reshetov, Vladimir, Dumusque, Xavier, Lovis, Christophe, Sosnowska, Danuta, Canto Martins, Bruno L., De Medeiros, Jose Renan, Delfosse, Xavier, Santos, Nuno, Rebolo, Rafael, Abreu, Manuel, Allain, Guillaume, Allart, Romain, Auger, Hugues, Barros, Susana, Bazinet, Luc, Blind, Nicolas, Boisse, Isabelle, Bonfils, Xavier, Bourrier, Vincent, Bovay, Sébastien, Broeg, Christopher, Brousseau, Denis, Bruniquel, Vincent, Cabral, Alexandre, Cadieux, Charles, Carmona, Andres, Carteret, Yann, Challita, Zalpha, Chazelas, Bruno, Cloutier, Ryan, Coelho, João M., Cointepas, Marion, Conod, Uriel, Cowan, Nicolas, Cristo, Eduardo, Gomes da Silva, João, Dauplaise, Laurie, Lima Gomes, Roseane, Delgado-Mena, Elisa, Ehrenreich, David, Faria, João, Figueira, Pedro, Forveille, Thierry, Frensch, Yolanda, Gagné, Jonathan, Genest, Frédéric, Genolet, Ludovic, González Hernández, Jonay I., Gracia Temich, Felix, Grieves, Nolan, Hernandez, Olivier, Hobson, Melissa J., Hoeijmakers, Jens, Kerley, Dan, Krishnamurthy, Vigneshwaran, Lafrenière, David, Lamontagne, Pierrot, Larue, Pierre, Leaf, Henry, Leão, Izan C., Lim, Olivia, Lo Curto, Gaspare, Martins, Allan M., Melo, Claudio, Messias, Yuri, Mignon, Lucile, Moranta, Leslie, Mordasini, Christoph, Al Moulla, Khaled, Mounzer, Dany, L'Heureux, Alexandrine, Nari, Nicola, Nielsen, Louise, Osborn, Ares, Parc, Lena, Pasquini, Luca, Passegger, Vera, Pelletier, Stefan, Peroux, Céline, Piaulet, Caroline, Plotnykov, Mykhaylo, Poulin-Girard, Anne-Sophie, Rasilla, José Luis, Saint-Antoine, Jonathan, Sarajic, Mirsad, Segovia, Alex, Seidel, Julia V., Ségransan, Damien, Silva, Ana Rita, Srivastava, Avidaan, Stefanov, Atanas K., Suárez Mascareño, Alejandro, Sordet, Michael, Teixeira, Márcio A., Udry, Sféphane, Valencia, Diana, Vallée, Philippe, Vandal, Thomas, Vaulato, Valentina, Wade, Gregg, Wardenier, Joost P., Wehbé, Bachar, Weisserman, Drew, Wevers, Ivan, and Zins, Gérard

Published
2024
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31. An optical metrology system for the measurement of the refractive index of glass

Author

Leite Inês and Cabral Alexandre

Subjects
Physics, QC1-999
Abstract

The measurement of the refractive index of parallel plated, optically simple, glass samples is a common and fundamental activity in numerous fields of expertise. This work aimed to optimize a known technique to a simple, cost-effective and reliable system to be implemented in a lab environment, with an accuracy in the results better than 10-2. A setup with a 632.8nm HeNe laser, automatic stage and CMOS camera was used and data was acquired with the help of LabVIEW controlling software. All system components were carefully controlled and optimized with the help of an uncertainty budget. Measurements had an associated uncertainty in the range from 10-3 to 10-4.

Published
2020
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48. Field-based assessment of the design of lysimeters for landfill final cover seepage control

Author

Kahale, Thierry, Ouédraogo, Ousmane, Duarte Neto, Mauro, Simard, Virginie, and Cabral, Alexandre R.

Abstract

ABSTRACTLysimeters are considered the most appropriate instrument for assessing percolations rates through landfill final covers. Their design, however, must take into consideration the unsaturated nature of water seepage, otherwise they may act as a sink or cause flow avoidance. The aim of this study was to investigate whether using a simple approach to lysimeter design produces reliable seepage control data. Two different design methods were compared using a three-year field database of suction and seepage data collected from large-scale lysimeters installed at the St-Nicephore landfill in Canada. The first, or control, whose side walls were as high as the thickness of the cover material, was inspired from lysimeters installed during the Alternative Cover Assessment Program (ACAP; USA). The second lysimeter was designed based on the proposed simple design methodology, which focuses on the unsaturated flow and hydraulic properties of the materials to determine the optimal wall height. Analysis of the database did not show any indication of significant preferential flow, or alteration of the flow regime by the second lysimeter, which collected as much percolation as the control one (less than 5% difference). The linear method has not been tested for extreme climatic conditions and the wall heights calculated using this method may be very high when designed for very fine-grained soil covers.

Published
2022
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49. Palladiferous placer gold from the Paraíba do Sul River in northern Rio de Janeiro (Brazil) and its geological implications

Author

Nunes da Rocha, Flávio França, Cabral, Alexandre Raphael, Lohmeier, Stephanie Gertrud, Tupinambá, Miguel, and Bertolino, Luiz Carlos

Abstract

Placer gold recovered from the Paraíba do Sul River, which flows along a high-grade shear zone in northern Rio de Janeiro, Brazil, has a distinctive component of palladiferous gold. Its finding, reported for the first time in the state of Rio de Janeiro, implies a hydrothermal system of high salinity at relatively low temperatures, in which metal transport is facilitated by hematite-rich rocks and generally precipitated at redox fronts. Such a hydrothermal system is not geologically manifested in the currently exposed high-grade shear zone. The finding of palladiferous gold suggests that its source was eroded during periods of increased denudation rates since the Lower Cretaceous, as indicated by apatite fission-track (AFT) data that have been reported for the region.

Published
2022
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