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1. 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, Cesar, 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, Acuña, Lorena, 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, Balestra, Andrea, Ball, Warrick, Ballans, Herve, Ballot, Jerome, Barban, Caroline, Barbary, Gaële, Barbieri, Mauro, Forteza, Sebastià 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, 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, Calderone, Flavia, Cameron, Robert, Cameron, Andrew, Campante, Tiago, 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, Jorgen, Church, Ross, Claret, Antonio, Clarke, Cathie, Claudi, Riccardo, Clermont, Lionel, Coelho, Hugo, Coelho, Joao, Cogato, Fabrizio, Colomé, Josep, Condamin, Mathieu, 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, de Plaa, Jelle, De Ridder, Joris, Deal, Morgan, Decin, Leen, Deeg, Hans, Degl'Innocenti, Scilla, Deheuvels, Sebastien, del Burgo, Carlos, Del Sordo, Fabio, Delgado-Mena, Elisa, Demangeon, Olivier, Denk, Tilmann, Derekas, Aliz, 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, Estrela, Inês, Evans, Dafydd Wyn, Fabbian, Damian, Fabrizio, Michele, Faria, João Pedro, Farina, Maria, Farinato, Jacopo, Feliz, Dax, Feltzing, Sofia, Fenouillet, Thomas, 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, Galli, Emanuele, Garcia, 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, Gorius, Nicolas, Gouel, Pierre-Vincent, Goulty, Duncan, Granata, Valentina, Grenfell, John Lee, Grießbach, Denis, Grolleau, Emmanuel, Grouffal, Salomé, Grziwa, Sascha, Guarcello, Mario Giuseppe, Gueguen, Loïc, Guenther, Eike Wolf, Guilhem, Terrasa, Guillerot, Lucas, 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, 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, Kučinskas, 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, 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, Mann, Andrew, Mantovan, Giacomo, Marafatto, Luca, Marconi, Marcella, Mardling, Rosemary, Marigo, Paola, Marinoni, Silvia, Marques, Érico, Marques, Joao Pedro, Marrese, Paola Maria, Marshall, Douglas, Perales, Silvia Martínez, Mary, David, Marzari, Francesco, Masana, Eduard, Mascher, Andrina, Mathis, Stéphane, Mathur, Savita, 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., Morales, Juan Carlos, Morales-Calderon, Maria, Morbidelli, Alessandro, Mordasini, Christoph, Moreau, Chrystel, Morel, Thierry, Morello, Guiseppe, Morin, Julien, Mortier, Annelies, Mosser, Benoît, 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, Stefano, 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, Quirrenbach160, ndreas, Reina6, 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, Rodríguez, María Teresa Rodrigo, 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, Santoli, Francesco, Santos, Ângela 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, Švanda, 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, Weingril, 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

2. The Challenges of the Nonlinear Regime for Physics-Informed Neural Networks

Author: Bonfanti, Andrea, Bruno, Giuseppe, and Cipriani, Cristina
Subjects: Computer Science - Machine Learning
Abstract: The Neural Tangent Kernel (NTK) viewpoint is widely employed to analyze the training dynamics of overparameterized Physics-Informed Neural Networks (PINNs). However, unlike the case of linear Partial Differential Equations (PDEs), we show how the NTK perspective falls short in the nonlinear scenario. Specifically, we establish that the NTK yields a random matrix at initialization that is not constant during training, contrary to conventional belief. Another significant difference from the linear regime is that, even in the idealistic infinite-width limit, the Hessian does not vanish and hence it cannot be disregarded during training. This motivates the adoption of second-order optimization methods. We explore the convergence guarantees of such methods in both linear and nonlinear cases, addressing challenges such as spectral bias and slow convergence. Every theoretical result is supported by numerical examples with both linear and nonlinear PDEs, and we highlight the benefits of second-order methods in benchmark test cases., Comment: 10 pages, 4 figures, appendix of 12 additional pages
Published: 2024

3. Discovery of two warm mini-Neptunes with contrasting densities orbiting the young K3V star TOI-815

Author: Psaridi, Angelica, Osborn, Hugh, Bouchy, François, Lendl, Monika, Parc, Léna, Billot, Nicolas, Broeg, Christopher, Sousa, Sérgio G., Adibekyan, Vardan, Attia, Omar, Bonfanti, Andrea, Chakraborty, Hritam, Collins, Karen A., Davoult, Jeanne, Delgado-Mena, Elisa, Grieves, Nolan, Guillot, Tristan, Heitzmann, Alexis, Helled, Ravit, Hellier, Coel, Jenkins, Jon M., Knierim, Henrik, Krenn, Andreas, Lissauer, JackJ., Luque, Rafael, Rapetti, David, Santos, Nuno C., Suárez, Olga, Venturini, Julia, Wilkin, Francis P., Wilson, Thomas G., Winn, Joshua N., Ziegler, Carl, Zingales, Tiziano, Alibert, Yann, Brandeker, Alexis, Egger, Jo Ann, Gandolfi, Davide, Hooton, Matthew J., Tuson, Amy, Ulmer-Moll, Solène, Abe, Lyu, Allart, Romain, Alonso, Roi, Anderson, David R., Anglada, Guillem, Bárczy, Tamas, Barrado, David, Barros, Susana C. C., Baumjohann, Wolfgang, Beck, Mathias, Beck, Thomas, Benz, Willy, Bonfils, Xavier, Borsato, Luca, Bourrier, Vincent, Ciardi, David R., Cameron, Andrew Collier, Charnoz, Sébastien, Cointepas, Marion, Csizmadia, Szilárd, Cubillos, Patricio, Curto, Gaspare Lo, Davies, Melvyn B., Daylan, Tansu, Deleuil, Magali, Deline, Adrien, Delrez, Laetitia, Demangeon, Olivier D. S., Demory, Brice-Olivier, Dorn, Caroline, Dumusque, Xavier, Ehrenreich, David, Erikson, Anders, Etangs, Alain Lecavelier des, Ferreras, Elena Diana de Miguel, Fortier, Andrea, Fossati, Luca, Frensch, Yolanda G. C., Fridlund, Malcolm, Gillon, Michaël, Güdel, Manuel, Günther, Maximilian N., Hagelberg, Janis, Helling, Christiane, Hoyer, Sergio, Isaak, Kate G., Kiss, Laszlo L., Lam, Kristine, Laskar, Jacques, Lavie, Baptiste, Lovis, Christophe, Magrin, Demetrio, Marafatto, Luca, Maxted, Pierre, McDermott, Scott, Mékarnia, Djamel, Mordasini, Christoph, Murgas, Felipe, Nascimbeni, Valerio, Nielsen, Louise D., Olofsson, Göran, Ottensamer, Roland, Pagano, Isabella, Pallé, Enric, Peter, Gisbert, Piotto, Giampaolo, Pollacco, Don, Queloz, Didier, Ragazzoni, Roberto, Ramos, Devin, Rando, Nicola, Rauer, Heike, Reimers, Christian, Ribas, Ignasi, Seager, Sara, Ségransan, Damien, Scandariato, Gaetano, Simon, Attila, Smith, Alexis M. S., Stalport, Manu, Steller, Manfred, Szabó, Gyula, Thomas, Nicolas, Pritchard, Tyler A., Udry, Stéphane, Van Damme, Carlos Corral, Van Grootel, Valérie, Villaver, Eva, Walter, Ingo, Walton, Nicholas, Watkins, Cristilyn N., and West, Richard G.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: We present the discovery and characterization of two warm mini-Neptunes transiting the K3V star TOI-815 in a K-M binary system. Analysis of the spectra and rotation period reveal it to be a young star with an age of $200^{+400}_{-200}$Myr. TOI-815b has a 11.2-day period and a radius of 2.94$\pm$0.05$\it{R_{\rm\mathrm{\oplus}}}$ with transits observed by TESS, CHEOPS, ASTEP, and LCOGT. The outer planet, TOI-815c, has a radius of 2.62$\pm$0.10$\it{R_{\rm\mathrm{\oplus}}}$, based on observations of three non-consecutive transits with TESS, while targeted CHEOPS photometry and radial velocity follow-up with ESPRESSO were required to confirm the 35-day period. ESPRESSO confirmed the planetary nature of both planets and measured masses of 7.6$\pm$1.5 $\it{M_{\rm \mathrm{\oplus}}}$ ($\rho_\mathrm{P}$=1.64$^{+0.33}_{-0.31}$gcm$^{-3}$) and 23.5$\pm$2.4$\it{M_{\rm\mathrm{\oplus}}}$ ($\rho_\mathrm{P}$=7.2$^{+1.1}_{-1.0}$gcm$^{-3}$) respectively. Thus, the planets have very different masses, unlike the usual similarity of masses in compact multi-planet systems. Moreover, our statistical analysis of mini-Neptunes orbiting FGK stars suggests that weakly irradiated planets tend to have higher bulk densities compared to those suffering strong irradiation. This could be ascribed to their cooler atmospheres, which are more compressed and denser. Internal structure modeling of TOI-815b suggests it likely has a H-He atmosphere constituting a few percent of the total planet mass, or higher if the planet is assumed to have no water. In contrast, the measured mass and radius of TOI-815c can be explained without invoking any atmosphere, challenging planetary formation theories. Finally, we infer from our measurements that the star is viewed close to pole-on, which implies a spin-orbit misalignment at the 3$\sigma$ level., Comment: 24 pages, 27 figures, 6 tables
Published: 2024

4. TESS and CHEOPS Discover Two Warm Sub-Neptunes Transiting the Bright K-dwarf HD 15906

Author: Tuson, Amy, Queloz, Didier, Osborn, Hugh P., Wilson, Thomas G., Hooton, Matthew J., Beck, Mathias, Lendl, Monika, Olofsson, Göran, Fortier, Andrea, Bonfanti, Andrea, Brandeker, Alexis, Buchhave, Lars A., Cameron, Andrew Collier, Ciardi, David R., Collins, Karen A., Gandolfi, Davide, Garai, Zoltan, Giacalone, Steven, da Silva, João Gomes, Howell, Steve B., Patel, Jayshil A., Persson, Carina M., Serrano, Luisa M., Sousa, Sérgio G., Ulmer-Moll, Solène, Vanderburg, Andrew, Ziegler, Carl, Alibert, Yann, Alonso, Roi, Anglada, Guillem, Bárczy, Tamas, Navascues, David Barrado, Barros, Susana C. C., Baumjohann, Wolfgang, Beck, Thomas, Benz, Willy, Billot, Nicolas, Bonfils, Xavier, Borsato, Luca, Broeg, Christopher, Cabrera, Juan, Charnoz, Sébastien, Conti, Dennis M., Csizmadia, Szilard, Cubillos, Patricio E., Davies, Melvyn B., Deleuil, Magali, Delrez, Laetitia, Demangeon, Olivier D. S., Demory, Brice-Olivier, Dragomir, Diana, Dressing, Courtney D., Ehrenreich, David, Erikson, Anders, Essack, Zahra, Farinato, Jacopo, Fossati, Luca, Fridlund, Malcolm, Furlan, Elise, Gill, Holden, Gillon, Michaël, Gnilka, Crystal L., Gonzales, Erica, Güdel, Manuel, Günther, Maximilian N., Hoyer, Sergio, Isaak, Kate G., Jenkins, Jon M., Kiss, Laszlo L., Laskar, Jacques, Latham, David W., Law, Nicholas, Etangs, Alain Lecavelier des, Curto, Gaspare Lo, Lovis, Christophe, Luque, Rafael, Magrin, Demetrio, Mann, Andrew W., Maxted, Pierre F. L., Mayor, Michel, McDermott, Scott, Mecina, Marko, Mordasini, Christoph, Mortier, Annelies, Nascimbeni, Valerio, Ottensamer, Roland, Pagano, Isabella, Pallé, Enric, Peter, Gisbert, Piotto, Giampaolo, Pollacco, Don, Pritchard, Tyler, Ragazzoni, Roberto, Rando, Nicola, Ratti, Francesco, Rauer, Heike, Ribas, Ignasi, Ricker, George R., Rieder, Martin, Santos, Nuno C., Savel, Arjun B., Scandariato, Gaetano, Schwarz, Richard P., Seager, Sara, Ségransan, Damien, Shporer, Avi, Simon, Attila E., Smith, Alexis M. S., Steller, Manfred, Stockdale, Chris, Szabó, Gyula M., Thomas, Nicolas, Torres, Guillermo, Tronsgaard, René, Udry, Stéphane, Ulmer, Bernd, Van Grootel, Valérie, Vanderspek, Roland, Venturini, Julia, Walton, Nicholas A., Winn, Joshua N., and Wohler, Bill
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: We report the discovery of two warm sub-Neptunes transiting the bright (G = 9.5 mag) K-dwarf HD 15906 (TOI 461, TIC 4646810). This star was observed by the Transiting Exoplanet Survey Satellite (TESS) in sectors 4 and 31, revealing two small transiting planets. The inner planet, HD 15906 b, was detected with an unambiguous period but the outer planet, HD 15906 c, showed only two transits separated by $\sim$ 734 days, leading to 36 possible values of its period. We performed follow-up observations with the CHaracterising ExOPlanet Satellite (CHEOPS) to confirm the true period of HD 15906 c and improve the radius precision of the two planets. From TESS, CHEOPS and additional ground-based photometry, we find that HD 15906 b has a radius of 2.24 $\pm$ 0.08 R$_\oplus$ and a period of 10.924709 $\pm$ 0.000032 days, whilst HD 15906 c has a radius of 2.93$^{+0.07}_{-0.06}$ R$_\oplus$ and a period of 21.583298$^{+0.000052}_{-0.000055}$ days. Assuming zero bond albedo and full day-night heat redistribution, the inner and outer planet have equilibrium temperatures of 668 $\pm$ 13 K and 532 $\pm$ 10 K, respectively. The HD 15906 system has become one of only six multiplanet systems with two warm ($\lesssim$ 700 K) sub-Neptune sized planets transiting a bright star (G $\leq$ 10 mag). It is an excellent target for detailed characterisation studies to constrain the composition of sub-Neptune planets and test theories of planet formation and evolution., Comment: 30 pages, 20 figures, 11 tables (including appendix). Published in MNRAS
Published: 2023
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5. On the Generalization of PINNs outside the training domain and the Hyperparameters influencing it

Author: Bonfanti, Andrea, Santana, Roberto, Ellero, Marco, and Gholami, Babak
Subjects: Computer Science - Machine Learning
Abstract: Physics-Informed Neural Networks (PINNs) are Neural Network architectures trained to emulate solutions of differential equations without the necessity of solution data. They are currently ubiquitous in the scientific literature due to their flexible and promising settings. However, very little of the available research provides practical studies that aim for a better quantitative understanding of such architecture and its functioning. In this paper, we perform an empirical analysis of the behavior of PINN predictions outside their training domain. The primary goal is to investigate the scenarios in which a PINN can provide consistent predictions outside the training area. Thereinafter, we assess whether the algorithmic setup of PINNs can influence their potential for generalization and showcase the respective effect on the prediction. The results obtained in this study returns insightful and at times counterintuitive perspectives which can be highly relevant for architectures which combines PINNs with domain decomposition and/or adaptive training strategies.
Published: 2023

6. TOI-836: A super-Earth and mini-Neptune transiting a nearby K-dwarf

Author: Hawthorn, Faith, Bayliss, Daniel, Wilson, Thomas G., Bonfanti, Andrea, Adibekyan, Vardan, Alibert, Yann, Sousa, Sérgio G., Collins, Karen A., Bryant, Edward M., Osborn, Ares, Armstrong, David J., Abe, Lyu, Acton, Jack S., Addison, Brett C., Agabi, Karim, Alonso, Roi, Alves, Douglas R., Anglada-Escudé, Guillem, Bárczy, Tamas, Barclay, Thomas, Barrado, David, Barros, Susana C. C., Baumjohann, Wolfgang, Bendjoya, Philippe, Benz, Willy, Bieryla, Allyson, Bonfils, Xavier, Bouchy, François, Brandeker, Alexis, Broeg, Christopher, Brown, David J. A., Burleigh, Matthew R., Buttu, Marco, Cabrera, Juan, Caldwell, Douglas A., Casewell, Sarah L., Charbonneau, David, Charnoz, Sébastian, Cloutier, Ryan, Cameron, Andrew Collier, Collins, Kevin I., Conti, Dennis M., Crouzet, Nicolas, Czismadia, Szilárd, Davies, Melvyn B., Deleuil, Magali, Delgado-Mena, Elisa, Delrez, Laetitia, Demangeon, Olivier D. S., Demory, Brice-Olivier, Dransfield, Georgina, Dumusque, Xavier, Egger, Jo Ann, Ehrenreich, David, Eigmüller, Philipp, Erickson, Anders, Essack, Zahra, Fortier, Andrea, Fossati, Luca, Fridlund, Malcolm, Günther, Maximilian N., Güdel, Manuel, Gandolfi, Davide, Gillard, Harvey, Gillon, Michaël, Gnilka, Crystal, Goad, Michael R., Goeke, Robert F., Guillot, Tristan, Hadjigeorghiou, Andreas, Hellier, Coel, Henderson, Beth A., Heng, Kevin, Hooton, Matthew J., Horne, Keith, Howell, Steve B., Hoyer, Sergio, Irwin, Jonathan M., Jenkins, James S., Jenkins, Jon M., Jensen, Eric L. N., Kane, Stephen R., Kendall, Alicia, Kielkopf, John F., Kiss, Laszlo L., Lacedelli, Gaia, Laskar, Jacques, Latham, David W., Etangs, Alain Lecavalier des, Leleu, Adrien, Lendl, Monika, Lillo-Box, Jorge, Lovis, Christophe, Mékarnia, Djamel, Massey, Bob, Masters, Tamzin, Maxted, Pierre F. L., Nascimbeni, Valerio, Nielsen, Louise D., O'Brien, Sean M., Olofsson, Göran, Osborn, Hugh P., Pagano, Isabella, Pallé, Enric, Persson, Carina M., Piotto, Giampaolo, Plavchan, Peter, Pollacco, Don, Queloz, Didier, Ragazzoni, Roberto, Rauer, Heike, Ribas, Ignasi, Ricker, George, Ségransan, Damien, Salmon, Sébastien, Santerne, Alexandre, Santos, Nuno C., Scandariato, Gaetano, Schmider, François-Xavier, Schwarz, Richard P., Seager, Sara, Shporer, Avi, Simon, Attila E., Smith, Alexis M. S., Srdoc, Gregor, Steller, Manfred, Suarez, Olga, Szabó, Gyula M., Teske, Johanna, Thomas, Nicolas, Tilbrook, Rosanna H., Triaud, Amaury H. M. J., Udry, Stéphane, Van Grootel, Valérie, Walton, Nicholas, Wang, Sharon X., Wheatley, Peter J., Winn, Joshua N., Wittenmyer, Robert A., and Zhang, Hui
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: We present the discovery of two exoplanets transiting TOI-836 (TIC 440887364) using data from TESS Sector 11 and Sector 38. TOI-836 is a bright ($T = 8.5$ mag), high proper motion ($\sim\,200$ mas yr$^{-1}$), low metallicity ([Fe/H]$\approx\,-0.28$) K-dwarf with a mass of $0.68\pm0.05$ M$_{\odot}$ and a radius of $0.67\pm0.01$ R$_{\odot}$. We obtain photometric follow-up observations with a variety of facilities, and we use these data-sets to determine that the inner planet, TOI-836 b, is a $1.70\pm0.07$ R$_{\oplus}$ super-Earth in a 3.82 day orbit, placing it directly within the so-called 'radius valley'. The outer planet, TOI-836 c, is a $2.59\pm0.09$ R$_{\oplus}$ mini-Neptune in an 8.60 day orbit. Radial velocity measurements reveal that TOI-836 b has a mass of $4.5\pm0.9$ M$_{\oplus}$ , while TOI-836 c has a mass of $9.6\pm2.6$ M$_{\oplus}$. Photometric observations show Transit Timing Variations (TTVs) on the order of 20 minutes for TOI-836 c, although there are no detectable TTVs for TOI-836 b. The TTVs of planet TOI-836 c may be caused by an undetected exterior planet.
Published: 2022
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7. Uncovering the true periods of the young sub-Neptunes orbiting TOI-2076

Author: Osborn, Hugh P., Bonfanti, Andrea, Gandolfi, Davide, Hedges, Christina, Leleu, Adrien, Fortier, Andrea, Futyan, David, Gutermann, Pascal, Maxted, Pierre F. L., Borsato, Luca, Collins, Karen A., da Silva, J. Gomes, Chew, Yilen Gómez Maqueo, Hooton, Matthew J., Lendl, Monika, Parviainen, Hannu, Salmon, Sébastien, Schanche, Nicole, Serrano, Luisa M., Sousa, Sergio G., Tuson, Amy, Ulmer-Moll, Solène, Van Grootel, Valerie, Wells, R. D., Wilson, Thomas G., Alibert, Yann, Alonso, Roi, Anglada, Guillem, Asquier, Joel, Navascues, David Barrado y, Baumjohann, Wolfgang, Beck, Thomas, Benz, Willy, Biondi, Federico, Bonfils, Xavier, Bouchy, Francois, Brandeker, Alexis, Broeg, Christopher, Bárczy, Tamas, Barros, S. C. C., Cabrera, Juan, Charnoz, Sébastien, Cameron, Andrew Collier, Csizmadia, Szilard, Davies, Melvyn B., Deleuil, Magali, Delrez, Laetitia, Demory, Brice-Olivier, Ehrenreich, David, Erikson, Anders, Fossati, Luca, Fridlund, Malcolm, Gillon, Michaël, Gómez-Muñoz, M. A., Güdel, Manuel, Heng, Kevin, Hoyer, Sergio, Isaak, Kate G., Kiss, Laszlo, Laskar, Jacques, Etangs, Alain Lecavelier des, Lovis, Christophe, Magrin, Demetrio, Malavolta, Luca, McCormac, James, Nascimbeni, Valerio, Olofsson, Göran, Ottensamer, Roland, Pagano, Isabella, Pallé, Enric, Peter, Gisbert, Piazza, Daniele, Piotto, Giampaolo, Pollacco, Don, Queloz, Didier, Ragazzoni, Roberto, Rando, Nicola, Rauer, Heike, Reimers, Christian, Ribas, Ignasi, Demangeon, Olivier D. S., Smith, Alexis M. S., Sabin, L., Santos, Nuno, Scandariato, Gaetano, Schroffenegger, U., Schwarz, Rick P., Shporer, Avi, Simon, Attila E., Steller, Manfred, Szabó, Gyula M., Ségransan, Damien, Thomas, Nicolas, Udry, Stéphane, Walter, Ingo, and Walton, Nicholas
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: Context: TOI-2076 is a transiting three-planet system of sub-Neptunes orbiting a bright (G = 8.9 mag), young ($340\pm80$ Myr) K-type star. Although a validated planetary system, the orbits of the two outer planets were unconstrained as only two non-consecutive transits were seen in TESS photometry. This left 11 and 7 possible period aliases for each. Aims: To reveal the true orbits of these two long-period planets, precise photometry targeted on the highest-probability period aliases is required. Long-term monitoring of transits in multi-planet systems can also help constrain planetary masses through TTV measurements. Methods: We used the MonoTools package to determine which aliases to follow, and then performed space-based and ground-based photometric follow-up of TOI-2076 c and d with CHEOPS, SAINT-EX, and LCO telescopes. Results: CHEOPS observations revealed a clear detection for TOI-2076 c at $P=21.01538^{+0.00084}_{-0.00074}$ d, and allowed us to rule out three of the most likely period aliases for TOI-2076 d. Ground-based photometry further enabled us to rule out remaining aliases and confirm the $P=35.12537\pm0.00067$ d alias. These observations also improved the radius precision of all three sub-Neptunes to $2.518\pm0.036$, $3.497\pm0.043$, and $3.232\pm0.063$ $R_\oplus$. Our observations also revealed a clear anti-correlated TTV signal between planets b and c likely caused by their proximity to the 2:1 resonance, while planets c and d appear close to a 5:3 period commensurability, although model degeneracy meant we were unable to retrieve robust TTV masses. Their inflated radii, likely due to extended H-He atmospheres, combined with low insolation makes all three planets excellent candidates for future comparative transmission spectroscopy with JWST., Comment: 18 pages, 7 figure, 8 tables. Accepted for publication in Astronomy & Astrophysics. Photometry available on CDS/Vizier. Python package presented for modelling duotransiting planet candidates available at https://github.com/hposborn/MonoTools. Modelling & figure-creation code available at https://github.com/hposborn/TOI2076
Published: 2022
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8. A pair of Sub-Neptunes transiting the bright K-dwarf TOI-1064 characterised with CHEOPS

Author: Wilson, Thomas G., Goffo, Elisa, Alibert, Yann, Gandolfi, Davide, Bonfanti, Andrea, Persson, Carina M., Cameron, Andrew Collier, Fridlund, Malcolm, Fossati, Luca, Korth, Judith, Benz, Willy, Deline, Adrien, Florén, Hans-Gustav, Guterman, Pascal, Adibekyan, Vardan, Hooton, Matthew J., Hoyer, Sergio, Leleu, Adrien, Mustill, Alexander James, Salmon, Sébastien, Sousa, Sérgio G., Suarez, Olga, Abe, Lyu, Agabi, Abdelkrim, Alonso, Roi, Anglada, Guillem, Asquier, Joel, Bárczy, Tamas, Navascues, David Barrado y, Barros, Susana C. C., Baumjohann, Wolfgang, Beck, Mathias, Beck, Thomas, Billot, Nicolas, Bonfils, Xavier, Brandeker, Alexis, Broeg, Christopher, Bryant, Edward M., Burleigh, Matthew R., Buttu, Marco, Cabrera, Juan, Charnoz, Sébastien, Ciardi, David R., Cloutier, Ryan, Cochran, William D., Collins, Karen A., Colón, Knicole D., Crouzet, Nicolas, Csizmadia, Szilard, Davies, Melvyn B., Deleuil, Magali, Delrez, Laetitia, Demangeon, Olivier, Demory, Brice-Olivier, Dragomir, Diana, Dransfield, Georgina, Ehrenreich, David, Erikson, Anders, Fortier, Andrea, Gan, Tianjun, Gill, Samuel, Gillon, Michaël, Gnilka, Crystal L., Grieves, Nolan, Grziwa, Sascha, Güdel, Manuel, Guillot, Tristan, Haldemann, Jonas, Heng, Kevin, Horne, Keith, Howell, Steve B., Isaak, Kate G., Jenkins, Jon M., Jensen, Eric L. N., Kiss, Laszlo, Lacedelli, Gaia, Lam, Kristine, Laskar, Jacques, Latham, David W., Etangs, Alain Lecavelier des, Lendl, Monika, Lester, Kathryn V., Levine, Alan M., Livingston, John, Lovis, Christophe, Luque, Rafael, Magrin, Demetrio, Marie-Sainte, Wenceslas, Maxted, Pierre F. L., Mayo, Andrew W., McLean, Brian, Mecina, Marko, Mékarnia, Djamel, Nascimbeni, Valerio, Nielsen, Louise D., Olofsson, Göran, Osborn, Hugh P., Osborne, Hannah L. M., Ottensamer, Roland, Pagano, Isabella, Pallé, Enric, Peter, Gisbert, Piotto, Giampaolo, Pollacco, Don, Queloz, Didier, Ragazzoni, Roberto, Rando, Nicola, Rauer, Heike, Redfield, Seth, Ribas, Ignasi, Ricker, George R., Rieder, Martin, Santos, Nuno C., Scandariato, Gaetano, Schmider, François-Xavier, Schwarz, Richard P., Scott, Nicholas J., Seager, Sara, Ségransan, Damien, Serrano, Luisa Maria, Simon, Attila E., Smith, Alexis M. S., Steller, Manfred, Stockdale, Chris, Szabó, Gyula, Thomas, Nicolas, Ting, Eric B., Triaud, Amaury H. M. J., Udry, Stéphane, Van Eylen, Vincent, Van Grootel, Valérie, Vanderspek, Roland K., Viotto, Valentina, Walton, Nicholas, and Winn, Joshua N.
Subjects: Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: We report the discovery and characterisation of a pair of sub-Neptunes transiting the bright K-dwarf TOI-1064 (TIC 79748331), initially detected in TESS photometry. To characterise the system, we performed and retrieved CHEOPS, TESS, and ground-based photometry, HARPS high-resolution spectroscopy, and Gemini speckle imaging. We characterise the host star and determine $T_{\rm eff, \star}=4734\pm67$ K, $R_{\star}=0.726\pm0.007$ $R_{\odot}$, and $M_{\star}=0.748\pm0.032$ $M_{\odot}$. We present a novel detrending method based on PSF shape-change modelling and demonstrate its suitability to correct flux variations in CHEOPS data. We confirm the planetary nature of both bodies and find that TOI-1064 b has an orbital period of $P_{\rm b}=6.44387\pm0.00003$ d, a radius of $R_{\rm b}=2.59\pm0.04$ $R_{\oplus}$, and a mass of $M_{\rm b}=13.5_{-1.8}^{+1.7}$ $M_{\oplus}$, whilst TOI-1064 c has an orbital period of $P_{\rm c}=12.22657^{+0.00005}_{-0.00004}$ d, a radius of $R_{\rm c}=2.65\pm0.04$ $R_{\oplus}$, and a 3$\sigma$ upper mass limit of 8.5 ${\rm M_{\oplus}}$. From the high-precision photometry we obtain radius uncertainties of $\sim$1.6%, allowing us to conduct internal structure and atmospheric escape modelling. TOI-1064 b is one of the densest, well-characterised sub-Neptunes, with a tenuous atmosphere that can be explained by the loss of a primordial envelope following migration through the protoplanetary disc. It is likely that TOI-1064 c has an extended atmosphere due to the tentative low density, however further RVs are needed to confirm this scenario and the similar radii, different masses nature of this system. The high-precision data and modelling of TOI-1064 b are important for planets in this region of mass-radius space, and it allows us to identify a trend in bulk density-stellar metallicity for massive sub-Neptunes that may hint at the formation of this population of planets., Comment: 30 pages, 24 figures, 6 tables including the Appendix; accepted for publication in MNRAS
Published: 2022
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9. Transit detection of the long-period volatile-rich super-Earth $\nu^2$ Lupi d with $CHEOPS$

Author: Delrez, Laetitia, Ehrenreich, David, Alibert, Yann, Bonfanti, Andrea, Borsato, Luca, Fossati, Luca, Hooton, Matthew J., Hoyer, Sergio, Pozuelos, Francisco J., Salmon, Sébastien, Sulis, Sophia, Wilson, Thomas G., Adibekyan, Vardan, Bourrier, Vincent, Brandeker, Alexis, Charnoz, Sébastien, Deline, Adrien, Guterman, Pascal, Haldemann, Jonas, Hara, Nathan, Oshagh, Mahmoudreza, Sousa, Sergio G., Van Grootel, Valérie, Alonso, Roi, Escudé, Guillem Anglada, Bárczy, Tamás, Barrado, David, Barros, Susana C. C., Baumjohann, Wolfgang, Beck, Mathias, Bekkelien, Anja, Benz, Willy, Billot, Nicolas, Bonfils, Xavier, Broeg, Christopher, Cabrera, Juan, Cameron, Andrew Collier, Davies, Melvyn B., Deleuil, Magali, Delisle, Jean-Baptiste, Demangeon, Olivier D. S., Demory, Brice-Olivier, Erikson, Anders, Fortier, Andrea, Fridlund, Malcolm, Futyan, David, Gandolfi, Davide, Muñoz, Antonio Garcia, Gillon, Michaël, Guedel, Manuel, Heng, Kevin, Kiss, László, Laskar, Jacques, Etangs, Alain Lecavelier des, Lendl, Monika, Lovis, Christophe, Maxted, Pierre F. L., Nascimbeni, Valerio, Olofsson, Göran, Osborn, Hugh P., Pagano, Isabella, Pallé, Enric, Piotto, Giampaolo, Pollacco, Don, Queloz, Didier, Rauer, Heike, Ragazzoni, Roberto, Ribas, Ignasi, Santos, Nuno C., Scandariato, Gaetano, Ségransan, Damien, Simon, Attila E., Smith, Alexis M. S., Steller, Manfred, Szabó, Gyula M., Thomas, Nicolas, Udry, Stéphane, and Walton, Nicholas A.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: Exoplanets transiting bright nearby stars are key objects for advancing our knowledge of planetary formation and evolution. The wealth of photons from the host star gives detailed access to the atmospheric, interior, and orbital properties of the planetary companions. $\nu^2$ Lupi (HD 136352) is a naked-eye ($V = 5.78$) Sun-like star that was discovered to host three low-mass planets with orbital periods of 11.6, 27.6, and 107.6 days via radial velocity monitoring (Udry et al. 2019). The two inner planets (b and c) were recently found to transit (Kane et al. 2020), prompting a photometric follow-up by the brand-new $CHaracterising\:ExOPlanets\:Satellite\:(CHEOPS)$. Here, we report that the outer planet d is also transiting, and measure its radius and mass to be $2.56\pm0.09$ $R_{\oplus}$ and $8.82\pm0.94$ $M_{\oplus}$, respectively. With its bright Sun-like star, long period, and mild irradiation ($\sim$5.7 times the irradiation of Earth), $\nu^2$ Lupi d unlocks a completely new region in the parameter space of exoplanets amenable to detailed characterization. We refine the properties of all three planets: planet b likely has a rocky mostly dry composition, while planets c and d seem to have retained small hydrogen-helium envelopes and a possibly large water fraction. This diversity of planetary compositions makes the $\nu^2$ Lupi system an excellent laboratory for testing formation and evolution models of low-mass planets., Comment: Published in Nature Astronomy. 60 pages, 18 Figures, 6 Tables. This is the authors' version of the manuscript. The final authenticated version is available online at https://www.nature.com/articles/s41550-021-01381-5
Published: 2021
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10. Detection of Ongoing Mass Loss from HD 63433c, a Young Mini Neptune

Author: Zhang, Michael, Knutson, Heather A., Wang, Lile, Dai, Fei, Santos, Leonardo A. dos, Fossati, Luca, Henry, Gregory W., Ehrenreich, David, Alibert, Yann, Hoyer, Sergio, Wilson, Thomas G., and Bonfanti, Andrea
Subjects: Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract: We detect Lyman $\alpha$ absorption from the escaping atmosphere of HD 63433c, a $R=2.67 R_\oplus$, $P=20.5$ d mini Neptune orbiting a young (440 Myr) solar analogue in the Ursa Major Moving Group. Using HST/STIS, we measure a transit depth of $11.1 \pm 1.5$% in the blue wing and $8 \pm 3$% in the red. This signal is unlikely to be due to stellar variability, but should be confirmed by an upcoming second visit with HST. We do not detect Lyman $\alpha$ absorption from the inner planet, a smaller $R=2.15 R_\oplus$ mini Neptune on a 7.1 d orbit. We use Keck/NIRSPEC to place an upper limit of 0.5% on helium absorption for both planets. We measure the host star's X-ray spectrum and FUV flux with XMM-Newton, and model the outflow from both planets using a 3D hydrodynamic code. This model provides a reasonable match to the light curve in the blue wing of the Lyman $\alpha$ line and the helium non-detection for planet c, although it does not explain the tentative red wing absorption or reproduce the excess absorption spectrum in detail. Its predictions of strong Lyman $\alpha$ and helium absorption from b are ruled out by the observations. This model predicts a much shorter mass loss timescale for planet b, suggesting that b and c are fundamentally different: while the latter still retains its hydrogen/helium envelope, the former has likely lost its primordial atmosphere., Comment: accepted by AJ
Published: 2021
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11. GJ 273: On the formation, dynamical evolution and habitability of a planetary system hosted by an M dwarf at 3.75 parsec

Author: Pozuelos, Francisco J., Suárez, Juan C., de Elía, Gonzalo C., Berdiñas, Zaira M., Bonfanti, Andrea, Dugaro, Agustín, Gillon, Michaël, Jehin, Emmanuël, Günther, Maximilian N., Van Grootel, Valérie, Garcia, Lionel J., Thuillier, Antoine, Delrez, Laetitia, and Rodón, Jose R.
Subjects: Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract: Planets orbiting low-mass stars such as M dwarfs are now considered a cornerstone in the search for life-harbouring planets. GJ273 is a planetary system orbiting an M dwarf only 3.75 pc away, composed of two confirmed planets, GJ273b and GJ273c, and two promising candidates, GJ273d and GJ273e. Planet GJ273b resides in the habitable zone. Currently, due to a lack of observed planetary transits, only the minimum masses of the planets are known.Despite being an interesting system, the GJ273 planetary system is still poorly studied. We aim at precisely determine the physical parameters of the individual planets, in particular to break the mass--inclination degeneracy to accurately determine the mass of the planets. Moreover, we present thorough characterisation of planet GJ273b in terms of its potential habitability. We explored the planetary formation and hydration phases of GJ273 during the first 100 Myr. Then, we analysed the stability of the system. We also searched for regions which may harbour minor bodies such as an asteroid belt and Kuiper belt analogues. We found that the four-planet configuration of the system allows us to break the mass--inclination degeneracy with the following masses: $2.89\leq M_{\mathrm{b}}\leq3.03\,\mathrm{M}_\oplus$, $1.18\leq M_{\mathrm{c}}\leq1.24\,\mathrm{M}_\oplus$, $10.80\leq M_{\mathrm{d}}\leq11.35\,\mathrm{M}_\oplus$, and $9.30\leq M_{\mathrm{e}}\leq9.70\,\mathrm{M}_\oplus$. That is an Earth-mass planet, a super-Earth and two mini-Neptunes. Moreover, GJ273b is found to be an efficient water captor and GJ273c likely a dry planet. Several stable regions are predicted where minor bodies might reside. We comprehensively discuss the habitability of GJ273b., Comment: 20 pages, 2 annexes, 12 figures, 3 tables (A&A in press)
Published: 2020
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12. MCMCI: A code to fully characterise an exoplanetary system

Author: Bonfanti, Andrea and Gillon, Michaël
Subjects: Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract: Useful information can be retrieved by analysing the transit light curve of a planet-hosting star or induced radial velocity oscillations. However, inferring the physical parameters of the planet, such as mass, size, and semi-major axis, requires preliminary knowledge of some parameters of the host star, especially its mass or radius, which are generally inferred through theoretical evolutionary models. We seek to present and test a whole algorithm devoted to the complete characterisation of an exoplanetary system thanks to the global analysis of photometric or radial velocity time series combined with observational stellar parameters derived either from spectroscopy or photometry. We developed an integrated tool called MCMCI. This tool combines the Markov chain Monte Carlo (MCMC) approach of analysing photometric or radial velocity time series with a proper interpolation within stellar evolutionary isochrones and tracks, known as isochrone placement, to be performed at each chain step, to retrieve stellar theoretical parameters such as age, mass, and radius. We tested the MCMCI on the HD 219134 multi-planetary system hosting two transiting rocky super Earths and on WASP-4, which hosts a bloated hot Jupiter. Even considering different input approaches, a final convergence was reached within the code, we found good agreement with the results already stated in the literature and we obtained more precise output parameters, especially concerning planetary masses. The MCMCI tool offers the opportunity to perform an integrated analysis of an exoplanetary system without splitting it into the preliminary stellar characterisation through theoretical models. Rather this approach favours a close interaction between light curve analysis and isochrones, so that the parameters recovered at each step of the MCMC enter as inputs for purposes of isochrone placement., Comment: 18 pages, 6 figures, 6 tables. Accepted for publication in A&A. Source code link: https://github.com/Bonfanti88/MCMCI
Published: 2019
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13. Effect of anodizing on high cycle fatigue behaviour of cast AlSi8Mg-T6 alloy

Author: Pavesi, Arianna, Bandiera, Marco, Mancini, Alessandro, Tsyupa, Bozhena, Bonfanti, Andrea, Casari, Daniele, Barella, Silvia, D'Errico, Fabrizio, and Bertasi, Federico
Published: 2023
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14. A super-Earth and two sub-Neptunes transiting the nearby and quiet M dwarf TOI-270

Author: Günther, Maximilian N., Pozuelos, Francisco J., Dittmann, Jason A., Dragomir, Diana, Kane, Stephen R., Daylan, Tansu, Feinstein, Adina D., Huang, Chelsea, Morton, Timothy D., Bonfanti, Andrea, Bouma, L. G., Burt, Jennifer, Collins, Karen A., Lissauer, Jack J., Matthews, Elisabeth, Montet, Benjamin T., Vanderburg, Andrew, Wang, Songhu, Winters, Jennifer G., Ricker, George R., Vanderspek, Roland K., Latham, David W., Seager, Sara, Winn, Joshua N., Jenkins, Jon M., Armstrong, James D., Barakoui, Khalid, Batalha, Natalie, Bean, Jacob L., Caldwell, Douglas A., Ciardi, David R., Collins, Kevin I., Crossfield, Ian, Fausnaugh, Michael, Furesz, Gabor, Gan, Tianjun, Gillon, Michaël, Guerrero, Natalia, Horne, Keith, Howell, Steve B., Ireland, Michael, Isopi, Giovanni, Jehin, Emmanuël, Kielkopf, John F., Lepine, Sebastien, Mallia, Franco, Matson, Rachel A., Myers, Gordon, Palle, Enric, Quinn, Samuel N., Relles, Howard M., Rojas-Ayala, Bárbara, Schlieder, Joshua, Sefako, Ramotholo, Shporer, Avi, Suárez, Juan C., Tan, Thiam-Guan, Ting, Eric B., Twicken, Joseph D., and Waite, Ian A.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: We report the Transiting Exoplanet Survey Satellite discovery of three small planets transiting one of the nearest and brightest M dwarf hosts to date, TOI-270 (TIC 259377017; K-mag 8.3; 22.5 parsec). The M3V-type star is transited by the super-Earth-sized TOI-270 b (1.247+0.089-0.083 R_earth) and the sub-Neptune-sized exoplanets TOI-270 c (2.42+-0.13 R_earth) and TOI-270 d (2.13+-0.12 R_earth). The planets orbit close to a mean-motion resonant chain, with periods (3.36, 5.66, and 11.38 days) near ratios of small integers (5:3 and 2:1). TOI-270 is a prime target for future studies since: 1) its near-resonance allows detecting transit timing variations for precise mass measurements and dynamical studies; 2) its brightness enables independent radial velocity mass measurements; 3) the outer planets are ideal for atmospheric characterisation via transmission spectroscopy; and 4) the quiet star enables future searches for habitable zone planets. Altogether, very few systems with small, temperate exoplanets are as suitable for such complementary and detailed characterisation as TOI-270., Comment: Published in Nature Astronomy, 3, 1099. 35 pages, 10 figures, 5 tables. This is the authors' version of the manuscript
Published: 2019
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15. Molecular tumour board at European Institute of Oncology: Report of the first three year activity of an Italian precision oncology experience

Author: Repetto, Matteo, Crimini, Edoardo, Boscolo Bielo, Luca, Guerini-Rocco, Elena, Ascione, Liliana, Bonfanti, Andrea, Zanzottera, Cristina, Mazzarella, Luca, Ranghiero, Alberto, Belli, Carmen, Criscitiello, Carmen, Esposito, Angela, Barberis, Massimo C.P., and Curigliano, Giuseppe
Published: 2023
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16. Carbonate precipitation and phosphate trapping by microbialite isolates from an alkaline insular lake (Bagno dell'Acqua, Pantelleria Island, Italy)

Author: Mazzoni, Cristina, primary, Piacentini, Agnese, additional, Di Bella, Letizia, additional, Aldega, Luca, additional, Perinelli, Cristina, additional, Conte, Aida Maria, additional, Ingrassia, Michela, additional, Ruspandini, Tania, additional, Bonfanti, Andrea, additional, Caraba, Benedetta, additional, Falese, Francesco Giuseppe, additional, Chiocci, Francesco Latino, additional, and Fazi, Stefano, additional
Published: 2024
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17. Book Review: Neoliberal Transformations of the Italian State: Understanding the Roots of the Crises by Adriano Cozzolino

Author: Bonfanti, Andrea, primary
Published: 2024
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18. Upgrading the Data2Action Framework: Results Deriving from Its Application in the Printing Industry

Author: Stoll, Oliver, West, Shaun, Rapaccini, Mario, Barbieri, Cosimo, Bonfanti, Andrea, Gombac, Andrea, van der Aalst, Wil, Series Editor, Mylopoulos, John, Series Editor, Rosemann, Michael, Series Editor, Shaw, Michael J., Series Editor, Szyperski, Clemens, Series Editor, Nóvoa, Henriqueta, editor, Drăgoicea, Monica, editor, and Kühl, Niklas, editor
Published: 2020
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19. Age consistency between exoplanet hosts and field stars

Author: Bonfanti, Andrea, Ortolani, Sergio, and Nascimbeni, Valerio
Subjects: Astrophysics - Solar and Stellar Astrophysics
Abstract: Transiting planets around stars are discovered mostly through photometric surveys. Unlike radial velocity surveys, photometric surveys do not tend to target slow rotators, inactive or metal-rich stars. Nevertheless, we suspect that observational biases could also impact transiting-planet hosts. This paper aims to evaluate how selection effects reflect on the evolutionary stage of both a limited sample of transiting-planet host stars (TPH) and a wider sample of planet-hosting stars detected through radial velocity analysis. Then, thanks to uniform derivation of stellar ages, a homogeneous comparison between exoplanet hosts and field star age distributions is developed. Stellar parameters have been computed through our custom-developed isochrone placement algorithm, according to PARSEC models. The notable aspects of our algorithm include the treatment of element diffusion, activity checks in terms of $\log{R'_{HK}}$ and $v\sin{i}$, and the evaluation of the stellar evolutionary speed in the Hertzsprung-Russel diagram in order to better constrain age. Working with TPH, the observational stellar mean density $\rho_{\star}$ allows us to compute stellar luminosity even if the distance is not available, by combining $\rho_{\star}$ with the spectroscopic $\log{g}$. The median value of the TPH ages is $\sim5$ Gyr. Even if this sample is not very large, however, the result is very similar to what we found for the sample of spectroscopic hosts, whose modal and median values are [3, 3.5) Gyr and $\sim4.8$ Gyr, respectively. Thus, these stellar samples suffer almost the same selection effects. We also conclude that the age of our Sun is consistent with the age distribution of solar neighbourhood MS stars with spectral types from late F to early K, regardless of whether they harbour planets or not. We considered the possibility that our selected samples are older than the average disc population., Comment: 13 pages, 1 longtable, 9 figures. Accepted by A&A
Published: 2015
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20. Revising the ages of planet-hosting stars

Author: Bonfanti, Andrea, Ortolani, Sergio, Piotto, Giampaolo, and Nascimbeni, Valerio
Subjects: Astrophysics - Solar and Stellar Astrophysics
Abstract: This article aims to measure the age of planet-hosting stars (SWP) through stellar tracks and isochrones computed with the \textsl{PA}dova \& T\textsl{R}ieste \textsl{S}tellar \textsl{E}volutionary \textsl{C}ode (PARSEC). We developed algorithms based on two different techniques for determining the ages of field stars: \emph{isochrone placement} and \emph{Bayesian estimation}. Their application to a synthetic sample of coeval stars shows the intrinsic limits of each method. For instance, the Bayesian computation of the modal age tends to select the extreme age values in the isochrones grid. Therefore, we used the isochrone placement technique to measure the ages of 317 SWP. We found that $\sim6\%$ of SWP have ages lower than 0.5 Gyr. The age distribution peaks in the interval [1.5, 2) Gyr, then it decreases. However, $\sim7\%$ of the stars are older than 11 Gyr. The Sun turns out to be a common star that hosts planets, when considering its evolutionary stage. Our SWP age distribution is less peaked and slightly shifted towards lower ages if compared with ages in the literature and based on the isochrone fit. In particular, there are no ages below 0.5 Gyr in the literature., Comment: 16 pages, 18 figures. Accepted by A&A
Published: 2014
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21. LHS 1903 provides evidence for gas-depleted formation of planets around M-dwarfs

Author: Wilson, Thomas, primary, Simpson, Anna, additional, Cameron, Andrew Collier, additional, Cloutier, Ryan, additional, Adibekyan, Vardan, additional, John, Ancy Anna, additional, Alibert, Y, additional, Stalport, Manu, additional, Egger, J, additional, Bonfanti, Andrea, additional, Billot, Nicolas, additional, Guterman, Pascal, additional, Maxted, Pierre, additional, Simon, Attila, additional, Sousa, Sergio, additional, Fridlund, Malcolm, additional, Beck, M, additional, Bekkelien, Anja, additional, Salmon, S, additional, Grootel, Valerie Van, additional, Fossati, Luca, additional, Mustill, Alexander, additional, Osborn, Hugh, additional, Zingales, Tiziano, additional, Hooton, M, additional, Affer, Laura, additional, Aigrain, Suzanne, additional, Alonso, Roi, additional, Anglada-Escude, G, additional, Antoniadis-Karnavas, Alexandros, additional, Barczy, T, additional, Barrado, David, additional, Barros, Susana, additional, Baumjohann, Wolfgang, additional, Beck, T, additional, Benz, W, additional, Biondi, Federico, additional, Bonfils, Xavier, additional, Borsato, Luca, additional, Brandeker, Alexis, additional, Broeg, Christopher, additional, Buchhave, Lars, additional, Buder, Maximilian, additional, Cabrera, Juan, additional, Gaxiola, S Carrazco, additional, Charnoz, Sébastien, additional, Ciardi, David, additional, Collins, Karen, additional, Collins, Kevin, additional, Cosentino, Rosario, additional, Csizmadia, Szilard, additional, Cubillos, P, additional, Dalal, Shweta, additional, Damasso, Mario, additional, Davenport, James, additional, Davies, Melvyn, additional, Deleuil, Magali, additional, Delrez, L, additional, Demangeon, Olivier, additional, Demory, Brice-Olivier, additional, DiTomasso, Victoria, additional, Dragomir, Diana, additional, Dressing, Courtney, additional, Dumusque, Xavier, additional, Ehrenreich, David, additional, Erikson, Anders, additional, Esparza-Borges, Emma, additional, Fortier, Andrea, additional, Fukuda, Izuru, additional, Fukui, Akihiko, additional, Gandolfi, Davide, additional, Ghedina, Adriano, additional, Giacalone, Steven, additional, Gill, Holden, additional, Gillon, Michaël, additional, Chew, Y Gomez Maqueo, additional, Güdel, Manuel, additional, Guerra, Pere, additional, Günther, Maximilian, additional, Hara, Nathan, additional, Harutyunyan, Avet, additional, Hayashi, Yuya, additional, Haywood, Raphaëlle, additional, Holcomb, Rae, additional, Horne, Keith, additional, Hoyer, S, additional, Huang, Chelsea, additional, Ikoma, Masahiro, additional, Isaak, K, additional, Jackman, James, additional, Jenkins, Jon, additional, Jensen, Eric, additional, Jontof-Hutter, Daniel, additional, Kawai, Yugo, additional, Kiss, Laszlo, additional, Lakeland, Ben, additional, Laskar, J, additional, Latham, David, additional, des Etangs, Alain Lecavelier, additional, Leleu, Adrien, additional, Lendl, Monika, additional, de Leon, J, additional, Lienhard, Florian, additional, López-Morales, Mercedes, additional, Lovis, Christophe, additional, Lund, Michael, additional, Luque, Rafael, additional, Magrin, D, additional, Malavolta, Luca, additional, Fiorenzano, Aldo, additional, Mayo, Andrew, additional, Mayor, Michel, additional, Mordasini, C, additional, Mortier, Annelies, additional, Murgas, Felipe, additional, Narita, Norio, additional, Nascimbeni, Valerio, additional, Nicholson, Belinda, additional, Olofsson, Göran, additional, Ottensamer, Roland, additional, Pagano, Isabella, additional, Palethorpe, Larissa, additional, Palle, Enric, additional, Parviainen, Hannu, additional, Pedani, Marco, additional, Pepe, Francesco, additional, Peter, Gisbert, additional, Pinamonti, Matteo, additional, Piotto, Giampaolo, additional, Pollacco, Don, additional, Poretti, Ennio, additional, Queloz, Didier, additional, Quinn, Sam, additional, Ragazzoni, R, additional, Rando, N, additional, Rapetti, David, additional, Ratti, F, additional, Rauer, Heike, additional, Rescigno, Federica, additional, Ribas, Ignasi, additional, Rice, William, additional, Ricker, George, additional, Robertson, Paul, additional, de Roche, Thierry, additional, Sabin, L, additional, Santos, Nuno, additional, Sasselov, Dimitar, additional, Savel, Arjun, additional, Scandariato, Gaetano, additional, Schanche, Nicole, additional, Schroffenegger, Urs, additional, Schwarz, Richard, additional, Seager, Sara, additional, Sefako, Ramotholo, additional, Ségransan, Damien, additional, Shporer, Avi, additional, Silva, André, additional, Smith, Alexis, additional, Sozzetti, Alessandro, additional, Steller, Manfred, additional, Szabo, Gyula, additional, Tamura, Motohide, additional, Thomas, Nicolas, additional, Tuson, Amy, additional, Udry, Stéphane, additional, Vanderburg, Andrew, additional, Vanderspek, Roland, additional, Venturini, J, additional, Verrecchia, Francesco, additional, Walton, Nicholas, additional, Watson, Christopher, additional, Wells, Robert, additional, Winn, Joshua, additional, Zambelli, Roberto, additional, and Ziegler, Carl, additional
Published: 2023
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22. Aluminum Alloys as Anodes for Aluminum Batteries

Author: Bandiera, Marco, primary, Pavesi, Arianna, additional, Valota, Giorgio, additional, Abello, Mary Angel, additional, Trombetta, Valentina, additional, Bonfanti, Andrea, additional, Mancini, Alessandro, additional, and Bertasi, Federico, additional
Published: 2023
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23. Interplay between Anodizing Parameters and Corrosion Resistance of Aluminum-Silicon Alloys

Author: Bandiera, Marco, primary, Abello, Mary Angel, additional, Pavesi, Arianna, additional, Trombetta, Valentina, additional, Valota, Giorgio, additional, Bonfanti, Andrea, additional, and Bertasi, Federico, additional
Published: 2023
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24. Upgrading the Data2Action Framework: Results Deriving from Its Application in the Printing Industry

Author: Stoll, Oliver, primary, West, Shaun, additional, Rapaccini, Mario, additional, Barbieri, Cosimo, additional, Bonfanti, Andrea, additional, and Gombac, Andrea, additional
Published: 2020
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25. A concept for reducing PM10 emissions for car brakes by 50%

Author: Perricone, Guido, Matějka, Vlastimil, Alemani, Mattia, Valota, Giorgio, Bonfanti, Andrea, Ciotti, Alessandro, Olofsson, Ulf, Söderberg, Anders, Wahlström, Jens, Nosko, Oleksii, Straffelini, Giovanni, Gialanella, Stefano, and Ibrahim, Metinoz
Published: 2018
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26. TESS and CHEOPS discover two warm sub-Neptunes transiting the bright K-dwarf HD 15906

Author: Tuson, A., Queloz, Didier, Osborn, Hugh P., Wilson, Thomas G., Hooton, Matthew J., Beck, Mathias, Lendl, Monika, Olofsson, Göran, Fortier, Andrea, Bonfanti, Andrea, Brandeker, Alexis, Buchhave, Lars A., Cameron, Andrew C., Ciardi, David R., Collins, Karen A., Gandolfi, Davide, Garai, Z., Giacalone, Steven, Gomes da Silva, João, and Howell, Steve B.
Subjects: techniques: photometric, planets and satellites: detection, photometric, planets and satellites: fundamental parameters, stars: fundamental parameters, stars: individual: HD 15906 (TOI 461, TIC 4646810) [techniques], stars: individual: HD 15906 (TOI 461, TIC 4646810)
Abstract: We report the discovery of two warm sub-Neptunes transiting the bright (G = 9.5 mag) K-dwarf HD 15906 (TOI 461, TIC 4646810). This star was observed by the Transiting Exoplanet Survey Satellite (TESS) in sectors 4 and 31, revealing two small transiting planets. The inner planet, HD 15906 b, was detected with an unambiguous period but the outer planet, HD 15906 c, showed only two transits separated by ∼ 734 d, leading to 36 possible values of its period. We performed follow-up observations with the CHaracterising ExOPlanet Satellite (CHEOPS) to confirm the true period of HD 15906 c and improve the radius precision of the two planets. From TESS, CHEOPS, and additional ground-based photometry, we find that HD 15906 b has a radius of 2.24 ± 0.08 R and a period of 10.924709 ± 0.000032 d, whilst HD 15906 c has a radius of 2.93+−000607 R and a period of 21.583298+−00000055000052 d. Assuming zero bond albedo and full day-night heat redistribution, the inner and outer planet have equilibrium temperatures of 668 ± 13 K and 532 ± 10 K, respectively. The HD 15906 system has become one of only six multiplanet systems with two warm (700 K) sub-Neptune sized planets transiting a bright star (G ≤ 10 mag). It is an excellent target for detailed characterization studies to constrain the composition of sub-Neptune planets and test theories of planet formation and evolution., Monthly Notices of the Royal Astronomical Society, 523 (2), ISSN:13652966, ISSN:0035-8711, ISSN:1365-2966
Published: 2023

27. A Novel Push-Pull Input Buffer for Wideband ADCs with Improved High-Frequency Linearity

Author: Scaletti, Lorenzo, primary, Bertulessi, Luca, additional, Cristofoli, Andrea, additional, and Bonfanti, Andrea, additional
Published: 2023
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28. A 2GS/s 11b 8x Interleaved ADC with 9.2 ENOB and 69.9dB SFDR in 28nm CMOS

Author: Ricci, Luca, primary, Scaletti, Lorenzo, additional, Bè, Gabriele, additional, Rocco, Michele, additional, Bertulessi, Luca, additional, Levantino, Salvatore, additional, Lacaita, Andrea, additional, Samori, Carlo, additional, and Bonfanti, Andrea, additional
Published: 2023
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29. A 250-MS/s 9.9-ENOB 80.7 dB-SFDR Top-Plate Input SAR ADC With Charge Linearization

Author: Zanoletti, Gabriele, Scaletti, Lorenzo, Be, Gabriele, Ricci, Luca, Rocco, Michele, Bertulessi, Luca, Samori, Carlo, and Bonfanti, Andrea
Abstract: This brief presents a linearity enhancement method, named charge linearization technique (CLT), for top-plate input successive approximation register (SAR) data converters. The proposed CLT removes the linearity degradation due to the non-linear parasitic capacitance of the comparator. Consequently, the constraint on the size of the comparator is relieved. An 11-bit redundant SAR converter featuring the proposed linearization method has been designed and fabricated in a 28-nm CMOS process. The converter achieves a 61.3-dB signal-to-noise-and-distortion ratio (SNDR) and 80.7-dB spurious-free dynamic range (SFDR) while running at 250 MS/s and consuming 5.04 mW from a 0.9-V supply. The aforementioned techniques enhances the SNDR and SFDR by up to 2.5 dB and 17.4 dB, respectively.
Published: 2024
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30. TOI-5678b: A 48-day transiting Neptune-mass planet characterized with CHEOPS and HARPS

Author: Ulmer-Moll, Solène, Osborn, Hugh P., Tuson, A., Egger, Jo A., Lendl, Monika, Maxted, Pierre, Bekkelien, Anja, Simon, Attila E., Olofsson, Göran, Adibekyan, Vardan, Alibert, Yann, Bonfanti, Andrea, Bouchy, François, Brandeker, Alexis, Fridlund, Malcolm, Gandolfi, Davide, Mordasini, Christoph, Persson, Carina M., Salmon, Sébastien, Serrano, Luisa M., and Queloz, Didier
Subjects: planets and satellites: detection, detection, planets and satellites: individual: TOI-5678, planets and satellites: gaseous planets, methods: data analysis [planets and satellites], methods: data analysis
Abstract: Context. A large sample of long-period giant planets has been discovered thanks to long-term radial velocity surveys, but only a few dozen of these planets have a precise radius measurement. Transiting gas giants are crucial targets for the study of atmospheric composition across a wide range of equilibrium temperatures and, more importantly, for shedding light on the formation and evolution of planetary systems. Indeed, compared to hot Jupiters, the atmospheric properties and orbital parameters of cooler gas giants are unaltered by intense stellar irradiation and tidal effects. Aims. We aim to identify long-period planets in the Transiting Exoplanet Survey Satellite (TESS) data as single or duo-transit events. Our goal is to solve the orbital periods of TESS duo-transit candidates with the use of additional space-based photometric observations and to collect follow-up spectroscopic observations in order to confirm the planetary nature and measure the mass of the candidates. Methods. We use the CHaracterising ExOPlanet Satellite (CHEOPS) to observe the highest-probability period aliases in order to discard or confirm a transit event at a given period. Once a period is confirmed, we jointly model the TESS and CHEOPS light curves along with the radial velocity datasets to measure the orbital parameters of the system and obtain precise mass and radius measurements. Results. We report the discovery of a long-period transiting Neptune-mass planet orbiting the G7-type star TOI-5678. Our spectroscopic analysis shows that TOI-5678 is a star with a solar metallicity. The TESS light curve of TOI-5678 presents two transit events separated by almost two years. In addition, CHEOPS observed the target as part of its Guaranteed Time Observation program. After four non-detections corresponding to possible periods, CHEOPS detected a transit event matching a unique period alias. Follow-up radial velocity observations were carried out with the ground-based high-resolution spectrographs CORALIE and HARPS. Joint modeling reveals that TOI-5678 hosts a 47.73 day period planet, and we measure an orbital eccentricity consistent with zero at 2σ. The planet TOI-5678 b has a mass of 20 ± 4 Earth masses (M) and a radius of 4.91 ± 0.08 R Using interior structure modeling, we find that TOI-5678 b is composed of a low-mass core surrounded by a large H/He layer with a mass of 3.2±1.7-1.3 M. Conclusions. TOI-5678 b is part of a growing sample of well-characterized transiting gas giants receiving moderate amounts of stellar insolation (11 S). Precise density measurement gives us insight into their interior composition, and the objects orbiting bright stars are suitable targets to study the atmospheric composition of cooler gas giants., Astronomy & Astrophysics, 674, ISSN:0004-6361, ISSN:1432-0746
Published: 2023

31. The geometric albedo of the hot Jupiter HD 189733b measured with CHEOPS

Author: Krenn, Andreas F., Lendl, Monika, Patel, Jayshil A., Carone, Ludmila, Deleuil, Magalie, Sulis, Sophia, Collier Cameron, Andrew, Deline, Adrien, Guterman, Pascal, Queloz, Didier, Fossati, Luca, Brandeker, Alexis, Heng, Kevin, Akinsanmi, Babatunde, Adibekyan, Vardan, Bonfanti, Andrea, Demangeon, Oliver D.S., Kitzmann, Daniel, Salmon, S., and Sousa, Sérgio G.
Subjects: planets and satellites: atmospheres, techniques: photometric, atmospheres, planets and satellites: individual: HD 189733b [planets and satellites], planets and satellites: individual: HD 189733b
Abstract: Context. Measurements of the occultation of an exoplanet at visible wavelengths allow us to determine the reflective properties of a planetary atmosphere. The observed occultation depth can be translated into a geometric albedo. This in turn aids in characterising the structure and composition of an atmosphere by providing additional information on the wavelength-dependent reflective qualities of the aerosols in the atmosphere. Aims. Our aim is to provide a precise measurement of the geometric albedo of the gas giant HD 189733b by measuring the occultation depth in the broad optical bandpass of CHEOPS (350-1100 nm). Methods. We analysed 13 observations of the occultation of HD 189733b performed by CHEOPS utilising the Python package PyCHEOPS. The resulting occultation depth is then used to infer the geometric albedo accounting for the contribution of thermal emission from the planet. We also aid the analysis by refining the transit parameters combining observations made by the TESS and CHEOPS space telescopes. Results. We report the detection of an 24.7 ± 4.5 ppm occultation in the CHEOPS observations. This occultation depth corresponds to a geometric albedo of 0.076 ± 0.016. Our measurement is consistent with models assuming the atmosphere of the planet to be cloud-free at the scattering level and absorption in the CHEOPS band to be dominated by the resonant Na doublet. Taking into account previous optical-light occultation observations obtained with the Hubble Space Telescope, both measurements combined are consistent with a super-stellar Na elemental abundance in the dayside atmosphere of HD 189733b. We further constrain the planetary Bond albedo to between 0.013 and 0.42 at 3σconfidence. Conclusions. We find that the reflective properties of the HD 189733b dayside atmosphere are consistent with a cloud-free atmosphere having a super-stellar metal content. When compared to an analogous CHEOPS measurement for HD 209458b, our data hint at a slightly lower geometric albedo for HD 189733b (0.076 ± 0.016) than for HD 209458b (0.096 ± 0.016), or a higher atmospheric Na content in the same modelling framework. While our constraint on the Bond albedo is consistent with previously published values, we note that the higher-end values of ∼0.4, as derived previously from infrared phase curves, would also require peculiarly high reflectance in the infrared, which again would make it more difficult to disentangle reflected and emitted light in the total observed flux, and therefore to correctly account for reflected light in the interpretation of those phase curves. Lower reported values for the Bond albedos are less affected by this ambiguity., Astronomy & Astrophysics, 672, ISSN:0004-6361, ISSN:1432-0746
Published: 2023

32. Bandwidth vs ZRO Stability Trade-Off in Lissajous Frequency Modulated MEMS Gyroscopes

Author: Bestetti, Marco, primary, Mussi, Giorgio, additional, Gattere, Gabriele, additional, Padovani, Christian, additional, Bonfanti, Andrea Giovanni, additional, and Langfelder, Giacomo, additional
Published: 2023
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33. TOI-836: A super-Earth and mini-Neptune transiting a nearby K-dwarf

Author: Hawthorn, Faith, primary, Bayliss, Daniel, additional, Wilson, Thomas G, additional, Bonfanti, Andrea, additional, Adibekyan, Vardan, additional, Alibert, Yann, additional, Sousa, Sérgio G, additional, Collins, Karen A, additional, Bryant, Edward M, additional, Osborn, Ares, additional, Armstrong, David J, additional, Abe, Lyu, additional, Acton, Jack S, additional, Addison, Brett C, additional, Agabi, Karim, additional, Alonso, Roi, additional, Alves, Douglas R, additional, Anglada-Escudé, Guillem, additional, Bárczy, Tamas, additional, Barclay, Thomas, additional, Barrado, David, additional, Barros, Susana C C, additional, Baumjohann, Wolfgang, additional, Bendjoya, Philippe, additional, Benz, Willy, additional, Bieryla, Allyson, additional, Bonfils, Xavier, additional, Bouchy, François, additional, Brandeker, Alexis, additional, Broeg, Christopher, additional, Brown, David J A, additional, Burleigh, Matthew R, additional, Buttu, Marco, additional, Cabrera, Juan, additional, Caldwell, Douglas A, additional, Casewell, Sarah L, additional, Charbonneau, David, additional, Charnoz, Sébastian, additional, Cloutier, Ryan, additional, Cameron, Andrew Collier, additional, Collins, Kevin I, additional, Conti, Dennis M, additional, Crouzet, Nicolas, additional, Czismadia, Szilárd, additional, Davies, Melvyn B, additional, Deleuil, Magali, additional, Delgado-Mena, Elisa, additional, Delrez, Laetitia, additional, Demangeon, Olivier D S, additional, Demory, Brice-Olivier, additional, Dransfield, Georgina, additional, Dumusque, Xavier, additional, Egger, Jo Ann, additional, Ehrenreich, David, additional, Eigmüller, Philipp, additional, Erickson, Anders, additional, Essack, Zahra, additional, Fortier, Andrea, additional, Fossati, Luca, additional, Fridlund, Malcolm, additional, Günther, Maximilian N, additional, Güdel, Manuel, additional, Gandolfi, Davide, additional, Gillard, Harvey, additional, Gillon, Michaël, additional, Gnilka, Crystal, additional, Goad, Michael R, additional, Goeke, Robert F, additional, Guillot, Tristan, additional, Hadjigeorghiou, Andreas, additional, Hellier, Coel, additional, Henderson, Beth A, additional, Heng, Kevin, additional, Hooton, Matthew J, additional, Horne, Keith, additional, Howell, Steve B, additional, Hoyer, Sergio, additional, Irwin, Jonathan M, additional, Jenkins, James S, additional, Jenkins, Jon M, additional, Jensen, Eric L N, additional, Kane, Stephen R, additional, Kendall, Alicia, additional, Kielkopf, John F, additional, Kiss, Laszlo L, additional, Lacedelli, Gaia, additional, Laskar, Jacques, additional, Latham, David W, additional, Etangs, Alain Lecavalier des, additional, Leleu, Adrien, additional, Lendl, Monika, additional, Lillo-Box, Jorge, additional, Lovis, Christophe, additional, Mékarnia, Djamel, additional, Massey, Bob, additional, Masters, Tamzin, additional, Maxted, Pierre F L, additional, Nascimbeni, Valerio, additional, Nielsen, Louise D, additional, O’Brien, Sean M, additional, Olofsson, Göran, additional, Osborn, Hugh P, additional, Pagano, Isabella, additional, Pallé, Enric, additional, Persson, Carina M, additional, Piotto, Giampaolo, additional, Plavchan, Peter, additional, Pollacco, Don, additional, Queloz, Didier, additional, Ragazzoni, Roberto, additional, Rauer, Heike, additional, Ribas, Ignasi, additional, Ricker, George, additional, Ségransan, Damien, additional, Salmon, Sébastien, additional, Santerne, Alexandre, additional, Santos, Nuno C, additional, Scandariato, Gaetano, additional, Schmider, François-Xavier, additional, Schwarz, Richard P, additional, Seager, Sara, additional, Shporer, Avi, additional, Simon, Attila E, additional, Smith, Alexis M S, additional, Srdoc, Gregor, additional, Steller, Manfred, additional, Suarez, Olga, additional, Szabó, Gyula M, additional, Teske, Johanna, additional, Thomas, Nicolas, additional, Tilbrook, Rosanna H, additional, Triaud, Amaury H M J, additional, Udry, Stéphane, additional, Van Grootel, Valérie, additional, Walton, Nicholas, additional, Wang, Sharon X, additional, Wheatley, Peter J, additional, Winn, Joshua N, additional, Wittenmyer, Robert A, additional, and Zhang, Hui, additional
Published: 2023
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34. A 250-MS/s 9.9-ENOB 80.7dB-SFDR Top-Plate Input SAR ADC With Charge Linearization

Author: Zanoletti, Gabriele, primary, Scaletti, Lorenzo, additional, Bè, Gabriele, additional, Ricci, Luca, additional, Rocco, Michele, additional, Bertulessi, Luca, additional, Samori, Carlo, additional, and Bonfanti, Andrea, additional
Published: 2023
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35. A Multilayer Neural Accelerator With Binary Activations Based on Phase-Change Memory

Author: Bertuletti, Marco, primary, Munoz-Martin, Irene, additional, Bianchi, Stefano, additional, Bonfanti, Andrea G., additional, and Ielmini, Daniele, additional
Published: 2023
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36. Sub-10 μHz/√Hz Measurement Instrumentation for 140-dB DR Frequency-Modulated MEMS Sensors

Author: Padovani, Christian, primary, Bestetti, Marco, additional, Valzasina, Carlo, additional, Bonfanti, Andrea Giovanni, additional, and Langfelder, Giacomo, additional
Published: 2023
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37. Role of the friction layer in the high-temperature pin-on-disc study of a brake material

Author: Verma, Piyush Chandra, Ciudin, Rodica, Bonfanti, Andrea, Aswath, Pranesh, Straffelini, Giovanni, and Gialanella, Stefano
Published: 2016
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38. TOI-1055 b: Neptunian planet characterised with HARPS, TESS, and CHEOPS

Author: Bonfanti, Andrea, Gandolfi, Davide, Egger, Jo Ann, Fossati, Luca, Cabrera, Jésus, Krenn, Andreas, Alibert, Yann, Benz, Willy, Billot, Nicolas, Florén, Hans-Gustav, Lendl, Monika, Adibekyan, Vardan, Salmon, S., Santos, Nuno C., Sousa, Sérgio G., Wilson, Thomas G., Barragán, Oscar, Collier Cameron, Andrew, Delrez, Laetitia, Esposito, Massimiliano, and Queloz, Didier
Subjects: techniques: photometric, radial velocities, planets and satellites: fundamental parameters, stars: fundamental parameters [techniques], techniques: radial velocities, stars: fundamental parameters
Abstract: Context. TOI-1055 is a Sun-like star known to host a transiting Neptune-sized planet on a 17.5-day orbit (TOI-1055 b). Radial velocity (RV) analyses carried out by two independent groups using nearly the same set of HARPS spectra have provided measurements of planetary masses that differ by ∼2σ. Aims. Our aim in this work is to solve the inconsistency in the published planetary masses by significantly extending the set of HARPS RV measurements and employing a new analysis tool that is able to account and correct for stellar activity. Our further aim was to improve the precision on measurements of the planetary radius by observing two transits of the planet with the CHEOPS space telescope. Methods. We fit a skew normal function to each cross correlation function extracted from the HARPS spectra to obtain RV measurements and hyperparameters to be used for the detrending. We evaluated the correlation changes of the hyperparameters along the RV time series using the breakpoint technique. We performed a joint photometric and RV analysis using a Markov chain Monte Carlo scheme to simultaneously detrend the light curves and the RV time series. Results. We firmly detected the Keplerian signal of TOI-1055 b, deriving a planetary mass of Mb = 20.4+2.6 −2.5 M⊕ (∼12%). This value is in agreement with one of the two estimates in the literature, but it is significantly more precise. Thanks to the TESS transit light curves combined with exquisite CHEOPS photometry, we also derived a planetary radius of Rb = 3.490+0.070 −0.064 R⊕ (∼1.9%). Our mass and radius measurements imply a mean density of ρb = 2.65+0.37 −0.35 g cm−3 (∼14%). We further inferred the planetary structure and found that TOI-1055 b is very likely to host a substantial gas envelope with a mass of 0.41+0.34 −0.20 M⊕ and a thickness of 1.05+0.30 −0.29R⊕. Conclusions. Our RV extraction combined with the breakpoint technique has played a key role in the optimal removal of stellar activity from the HARPS time series, enabling us to solve the tension in the planetary mass values published so far for TOI-1055 b., Astronomy & Astrophysics, 671, ISSN:0004-6361, ISSN:1432-0746
Published: 2023

39. A full transit of v2 Lupi d and the search for an exomoon in its Hill sphere with CHEOPS

Author: Ehrenreich, David, Delrez, Laetitia, Akinsanmi, Babatunde, Wilson, Thomas G., Bonfanti, Andrea, Beck, Mathias, Benz, Willy, Hoyer, Sergio, Queloz, Didier, Alibert, Yann, Charnoz, Sébastien, Collier Cameron, Andrew, Deline, Adrien, Hooton, Matthew, Lendl, Monika, Olofsson, Göran, Sousa, Sérgio G., Adibekyan, Vardan, Alonso, Roi, and Anglada, Guillem
Subjects: planets and satellites: detection, planets and satellites: general, planets and satellites: individual: HD 136352, detection, planets and satellites: general [planets and satellites]
Abstract: The planetary system around the naked-eye star v2 Lupi (HD 136352; TOI-2011) is composed of three exoplanets with masses of 4.7, 11.2, and 8.6 Earth masses (M⊕). The TESS and CHEOPS missions revealed that all three planets are transiting and have radii straddling the radius gap separating volatile-rich and volatile-poor super-earths. Only a partial transit of planet d had been covered so we re-observed an inferior conjunction of the long-period 8.6 M⊕ exoplanet v2 Lup d with the CHEOPS space telescope. We confirmed its transiting nature by covering its whole 9.1 h transit for the first time. We refined the planet transit ephemeris to P = 107.13610.0022+0.0019 days and Tc = 2459009.77590.0096+0.0101 BJDTDB, improving by ~40 times on the previously reported transit timing uncertainty. This refined ephemeris will enable further follow-up of this outstanding long-period transiting planet to search for atmospheric signatures or explore the planet s Hill sphere in search for an exomoon. In fact, the CHEOPS observations also cover the transit of a large fraction of the planet s Hill sphere, which is as large as the Earth s, opening the tantalising possibility of catching transiting exomoons. We conducted a search for exomoon signals in this single-epoch light curve but found no conclusive photometric signature of additional transiting bodies larger than Mars. Yet, only a sustained follow-up of v2 Lup d transits will warrant a comprehensive search for a moon around this outstanding exoplanet., Astronomy & Astrophysics, 671, ISSN:0004-6361, ISSN:1432-0746
Published: 2023
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40. On the Hyperparameters influencing a PINN's generalization beyond the training domain

Author: Bonfanti, Andrea, Santana, Roberto, Ellero, Marco, and Gholami, Babak
Subjects: FOS: Computer and information sciences, Computer Science - Machine Learning, Machine Learning (cs.LG)
Abstract: Physics-Informed Neural Networks (PINNs) are Neural Network architectures trained to emulate solutions of differential equations without the necessity of solution data. They are currently ubiquitous in the scientific literature due to their flexible and promising settings. However, very little of the available research provides practical studies that aim for a better quantitative understanding of such architecture and its functioning. In this paper, we analyze the performance of PINNs for various architectural hyperparameters and algorithmic settings based on a novel error metric and other factors such as training time. The proposed metric and approach are tailored to evaluate how well a PINN generalizes to points outside its training domain. Besides, we investigate the effect of the algorithmic setup on the outcome prediction of a PINN, inside and outside its training domain, to explore the effect of each hyperparameter. Through our study, we assess how the algorithmic setup of PINNs influences their potential for generalization and deduce the settings which maximize the potential of a PINN for accurate generalization. The study that we present returns insightful and at times counterintuitive results on PINNs. These results can be useful in PINN applications when defining the model and evaluating it.
Published: 2023
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41. Publisher Correction: A super-Earth and two sub-Neptunes transiting the nearby and quiet M dwarf TOI-270

Author: Günther, Maximilian N., Pozuelos, Francisco J., Dittmann, Jason A., Dragomir, Diana, Kane, Stephen R., Daylan, Tansu, Feinstein, Adina D., Huang, Chelsea X., Morton, Timothy D., Bonfanti, Andrea, Bouma, L. G., Burt, Jennifer, Collins, Karen A., Lissauer, Jack J., Matthews, Elisabeth, Montet, Benjamin T., Vanderburg, Andrew, Wang, Songhu, Winters, Jennifer G., Ricker, George R., Vanderspek, Roland K., Latham, David W., Seager, Sara, Winn, Joshua N., Jenkins, Jon M., Armstrong, James D., Barkaoui, Khalid, Batalha, Natalie, Bean, Jacob L., Caldwell, Douglas A., Ciardi, David R., Collins, Kevin I., Crossfield, Ian, Fausnaugh, Michael, Furesz, Gabor, Gan, Tianjun, Gillon, Michaël, Guerrero, Natalia, Horne, Keith, Howell, Steve B., Ireland, Michael, Isopi, Giovanni, Jehin, Emmanuël, Kielkopf, John F., Lepine, Sebastien, Mallia, Franco, Matson, Rachel A., Myers, Gordon, Palle, Enric, Quinn, Samuel N., Relles, Howard M., Rojas-Ayala, Bárbara, Schlieder, Joshua, Sefako, Ramotholo, Shporer, Avi, Suárez, Juan C., Tan, Thiam-Guan, Ting, Eric B., Twicken, Joseph D., and Waite, Ian A.
Published: 2019
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42. La dissidenza comunista italiana, Trockij e le origini della Quarta Internazionale. 1928-1938/The Twilight of World Trotskyism.

Author: Bonfanti, Andrea
Subjects: SOCIAL scientists, POLITICAL parties, COMMUNISM, ANTI-imperialist movements, CLASS politics
Published: 2023

43. Full-digital output ASIC for Lissajous Frequency Modulated MEMS Gyroscopes

Author: Bestetti, Marco, primary, Bonfanti, Andrea Giovanni, additional, Falorni, Luca, additional, Gianollo, Matteo, additional, Padovani, Christian, additional, and Langfelder, Giacomo, additional
Published: 2022
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44. The stable climate of KELT-9b

Author: Jones, Kathryn, Morris, Brett M., Demory, Brice-Olivier, Heng, Kevin, Hooton, Matthew J., Billot, Nicolas, Ehrenreich, David, Hoyer, Sergio, Simon, Attila E., Lendl, Monika, Demangeon, Oliver D.S., Sousa, Sérgio G., Bonfanti, Andrea, Wilson, Thomas G., Salmon, Sébastien, Csizmadia, Szilárd, Parviainen, Hannu, Bruno, Giovanni, Alibert, Yann, Alonso, Roi, and Queloz, Didier
Subjects: planets and satellites: atmospheres, techniques: photometric, instrumentation: photometers, occultations, photometric, planets and satellites: gaseous planets, eclipses, occultations [techniques]
Abstract: Even among the most irradiated gas giants, so-called ultra-hot Jupiters, KELT-9b stands out as the hottest planet thus far discovered with a dayside temperature of over 4500 K. At these extreme irradiation levels, we expect an increase in heat redistribution efficiency and a low Bond albedo owed to an extended atmosphere with molecular hydrogen dissociation occurring on the planetary dayside. We present new photometric observations of the KELT-9 system throughout 4 full orbits and 9 eparate occultations obtained by the 30 cm space telescope CHEOPS. The CHEOPS bandpass, located at optical wavelengths, captures the peak of the thermal emission spectrum of KELT-9b. In this work we simultaneously analyse CHEOPS phase curves along with public phase curves from TESS and Spitzer to infer joint constraints on the phase curve variation, gravity-darkened transits, and occultation depth in three bandpasses, as well as derive 2D temperature maps of the atmosphere at three different depths. We find a day-night heat redistribution efficiency of ∼0.3 which confirms expectations of enhanced energy transfer to the planetary nightside due to dissociation and ecombination of molecular hydrogen. We also calculate a Bond albedo consistent with zero. We find no evidence of variability of the brightness temperature of the planet, excluding variability greater than 1% (1σ)., Astronomy & Astrophysics, 666, ISSN:0004-6361, ISSN:1432-0746
Published: 2022

45. A 70.7-dB SNDR 100-kS/s 14-b SAR ADC with attenuation capacitance calibration in 0.35-µm CMOS

Author: Brenna, Stefano, Bonfanti, Andrea, and Lacaita, Andrea Leonardo
Published: 2016
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46. Chemical Characterization of Nanoparticle Emissions from Brakes - The nPETS Project

Author: Mancini, Alessandro, primary, Tsyupa, Bozhena, additional, Federici, Matteo, additional, Leonardi, Mara, additional, Piglione, Alessandro, additional, Bandiera, Marco, additional, Bonfanti, Andrea, additional, and Bertasi, Federico, additional
Published: 2022
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47. Interplay between Microstructure and Anodizability in Aluminum Alloy Brake Calipers

Author: Bandiera, Marco, primary, Abello, Mary Angel, additional, Pavesi, Arianna, additional, Trombetta, Valentina, additional, Valota, Giorgio, additional, Bonfanti, Andrea, additional, Mancini, Alessandro, additional, and Bertasi, Federico, additional
Published: 2022
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48. A 900-MS/s SAR-Based Time-Interleaved ADC With a Fully Programmable Interleaving Factor and On-Chip Scalable Background Calibrations

Author: Be, Gabriele, primary, Parisi, Angelo, additional, Bertulessi, Luca, additional, Ricci, Luca, additional, Scaletti, Lorenzo, additional, Mercandelli, Mario, additional, Lacaita, Andrea L., additional, Levantino, Salvatore, additional, Samori, Carlo, additional, and Bonfanti, Andrea, additional
Published: 2022
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49. A 10.2-ENOB, 150-MS/s Redundant SAR ADC With a Quasi-Monotonic Switching Algorithm for Time-Interleaved Converters

Author: Scaletti, Lorenzo, primary, Be, Gabriele, additional, Parisi, Angelo, additional, Bertulessi, Luca, additional, Ricci, Luca, additional, Mercandelli, Mario, additional, Levantino, Salvatore, additional, Samori, Carlo, additional, and Bonfanti, Andrea, additional
Published: 2022
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50. Concurrent Effect of Redundancy and Switching Algorithms in SAR ADCs

Author: Ricci, Luca, primary, Scaletti, Lorenzo, additional, Be, Gabriele, additional, Bertulessi, Luca, additional, Levantino, Salvatore, additional, Samori, Carlo, additional, and Bonfanti, Andrea, additional
Published: 2022
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