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3,102 results on '"West, Richard"'

1. TOI-2490b- The most eccentric brown dwarf transiting in the brown dwarf desert

Author

Henderson, Beth A., Casewell, Sarah L., Jordán, Andrés, Brahm, Rafael, Henning, Thomas, Gill, Samuel, Mayorga, L. C., Ziegler, Carl, Stassun, Keivan G., Goad, Michael R., Acton, Jack, Alves, Douglas R., Anderson, David R., Apergis, Ioannis, Armstrong, David J., Bayliss, Daniel, Burleigh, Matthew R., Dragomir, Diana, Gillen, Edward, Günther, Maximilian N., Hedges, Christina, Hesse, Katharine M., Hobson, Melissa J., Jenkins, James S., Jenkins, Jon M., Kendall, Alicia, Lendl, Monika, Lund, Michael B., McCormac, James, Moyano, Maximiliano, Osborn, Ares, Pinto, Marcelo Tala, Ramsay, Gavin, Rapetti, David, Saha, Suman, Seager, Sara, Trifonov, Trifon, Udry, Stéphane, Vines, Jose I., West, Richard G., Wheatley, Peter J., Winn, Joshua N., and Zivave, Tafadzwa

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

We report the discovery of the most eccentric transiting brown dwarf in the brown dwarf desert, TOI02490b. The brown dwarf desert is the lack of brown dwarfs around main sequence stars within $\sim3$~AU and is thought to be caused by differences in formation mechanisms between a star and planet. To date, only $\sim40$ transiting brown dwarfs have been confirmed. \systemt is a $73.6\pm2.4$ \mjupnospace, $1.00\pm0.02$ \rjup brown dwarf orbiting a $1.004_{-0.022}^{+0.031}$ \msunnospace, $1.105_{-0.012}^{+0.012}$ \rsun sun-like star on a 60.33~d orbit with an eccentricity of $0.77989\pm0.00049$. The discovery was detected within \tess sectors 5 (30 minute cadence) and 32 (2 minute and 20 second cadence). It was then confirmed with 31 radial velocity measurements with \feros by the WINE collaboration and photometric observations with the Next Generation Transit Survey. Stellar modelling of the host star estimates an age of $\sim8$~Gyr, which is supported by estimations from kinematics likely placing the object within the thin disc. However, this is not consistent with model brown dwarf isochrones for the system age suggesting an inflated radius. Only one other transiting brown dwarf with an eccentricity higher than 0.6 is currently known in the brown dwarf desert. Demographic studies of brown dwarfs have suggested such high eccentricity is indicative of stellar formation mechanisms., Comment: Accepted for publication in MNRAS, 18 pages, 14 figures

Published
2024

3. 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

4. TOI-2447 b / NGTS-29 b: a 69-day Saturn around a Solar analogue

Author

Gill, Samuel, Bayliss, Daniel, Ulmer-Moll, Solène, Wheatley, Peter J., Brahm, Rafael, Anderson, David R., Armstrong, David, Apergis, Ioannis, Alves, Douglas R., Burleigh, Matthew R., Butler, R. P., Bouchy, François, Battley, Matthew P., Bryant, Edward M., Bieryla, Allyson, Crane, Jeffrey D., Collins, Karen A., Casewell, Sarah L., Carleo, Ilaria, Claringbold, Alastair B., Dalba, Paul A., Dragomir, Diana, Eigmüller, Philipp, Eberhardt, Jan, Fausnaugh, Michael, Günther, Maximilian N., Grieves, Nolan, Goad, Michael R., Gillen, Edward, Hagelberg, Janis, Hobson, Melissa, Hedges, Christina, Henderson, Beth A., Hawthorn, Faith, Henning, Thomas, Jones, Matías I., Jordán, Andrés, Jenkins, James S., Kunimoto, Michelle, Krenn, Andreas F., Kendall, Alicia, Lendl, Monika, McCormac, James, Moyano, Maximiliano, Torres-Miranda, Pascal, Nielsen, Louise D., Osborn, Ares, Otegi, Jon, Osborn, Hugh, Quinn, Samuel N., Rodriguez, Joseph E., Ramsay, Gavin, Schlecker, Martin, Shectman, Stephen A., Seager, Sara, Tilbrook, Rosanna H., Trifonov, Trifon, Teske, Johanna K., Udry, Stephane, Vines, Jose I., West, Richard R., Wohler, Bill, Winn, Joshua N., Wang, Sharon X., Zhou, George, and Zivave, Tafadzwa

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Discovering transiting exoplanets with relatively long orbital periods ($>$10 days) is crucial to facilitate the study of cool exoplanet atmospheres ($T_{\rm eq} < 700 K$) and to understand exoplanet formation and inward migration further out than typical transiting exoplanets. In order to discover these longer period transiting exoplanets, long-term photometric and radial velocity campaigns are required. We report the discovery of TOI-2447 b ($=$ NGTS-29b), a Saturn-mass transiting exoplanet orbiting a bright (T=10.0) Solar-type star (T$_{\rm eff}$=5730 K). TOI-2447 b was identified as a transiting exoplanet candidate from a single transit event of 1.3% depth and 7.29 h duration in $TESS$ Sector 31 and a prior transit event from 2017 in NGTS data. Four further transit events were observed with NGTS photometry which revealed an orbital period of P=69.34 days. The transit events establish a radius for TOI-2447 b of $0.865 \pm 0.010\rm R_{\rm J}$, while radial velocity measurements give a mass of $0.386 \pm 0.025 \rm M_{\rm J}$. The equilibrium temperature of the planet is $414$ K, making it much cooler than the majority of $TESS$ planet discoveries. We also detect a transit signal in NGTS data not caused by TOI-2447 b, along with transit timing variations and evidence for a $\sim$150 day signal in radial velocity measurements. It is likely that the system hosts additional planets, but further photometry and radial velocity campaigns will be needed to determine their parameters with confidence. TOI-2447 b/NGTS-29b joins a small but growing population of cool giants that will provide crucial insights into giant planet composition and formation mechanisms., Comment: 16 pages, 12 figures. Accepted for publication in MNRAS

Published
2024

5. Planet Hunters NGTS: New Planet Candidates from a Citizen Science Search of the Next Generation Transit Survey Public Data

Author

O'Brien, Sean M., Schwamb, Megan E., Gill, Samuel, Watson, Christopher A., Burleigh, Matthew R., Kendall, Alicia, Anderson, David R., Vines, José I., Jenkins, James S., Alves, Douglas R., Trouille, Laura, Ulmer-Moll, Solène, Bryant, Edward M., Apergis, Ioannis, Battley, Matthew P., Bayliss, Daniel, Eisner, Nora L., Gillen, Edward, Goad, Michael R., Günther, Maximilian N., Henderson, Beth A., Heo, Jeong-Eun, Jackson, David G., Lintott, Chris, McCormac, James, Moyano, Maximiliano, Nielsen, Louise D., Osborn, Ares, Saha, Suman, Sefako, Ramotholo R., Stephens, Andrew W., Tilbrook, Rosanna H., Udry, Stéphane, West, Richard G., Wheatley, Peter J., Zivave, Tafadzwa, Lim, See Min, and Sainio, Arttu

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We present the results from the first two years of the Planet Hunters NGTS citizen science project, which searches for transiting planet candidates in data from the Next Generation Transit Survey (NGTS) by enlisting the help of members of the general public. Over 8,000 registered volunteers reviewed 138,198 light curves from the NGTS Public Data Releases 1 and 2. We utilize a user weighting scheme to combine the classifications of multiple users to identify the most promising planet candidates not initially discovered by the NGTS team. We highlight the five most interesting planet candidates detected through this search, which are all candidate short-period giant planets. This includes the TIC-165227846 system that, if confirmed, would be the lowest-mass star to host a close-in giant planet. We assess the detection efficiency of the project by determining the number of confirmed planets from the NASA Exoplanet Archive and TESS Objects of Interest (TOIs) successfully recovered by this search and find that 74% of confirmed planets and 63% of TOIs detected by NGTS are recovered by the Planet Hunters NGTS project. The identification of new planet candidates shows that the citizen science approach can provide a complementary method to the detection of exoplanets with ground-based surveys such as NGTS., Comment: 42 pages, 20 figures, 17 tables. To be published in AJ

Published
2024
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6. NGTS-28Ab: A short period transiting brown dwarf

Author

Henderson, Beth A., Casewell, Sarah L., Goad, Michael R., Acton, Jack S., Günther, Maximilian N., Nielsen, Louise D., Burleigh, Matthew R., Belardi, Claudia, Tilbrook, Rosanna H., Turner, Oliver, Howell, Steve B., Clark, Catherine A., Littlefield, Colin, Barkaoui, Khalid, Alves, Douglas R., Anderson, David R., Bayliss, Daniel, Bouchy, Francois, Bryant, Edward M., Dransfield, George, Ducrot, Elsa, Eigmüller, Philipp, Gill, Samuel, Gillen, Edward, Gillon, Michaël, Hawthorn, Faith, Hooton, Matthew J., Jackman, James A. G., Jehin, Emmanuel, Jenkins, James S., Kendall, Alicia, Lendl, Monika, McCormac, James, Moyano, Maximiliano, Pedersen, Peter Pihlmann, Pozuelos, Francisco J., Ramsay, Gavin, Sefako, Ramotholo R., Timmermans, Mathilde, Triaud, Amaury H. M. J., Udry, Stephane, Vines, Jose I., Watson, Christopher A., West, Richard G., Wheatley, Peter J., and Zúñiga-Fernández, Sebastián

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

We report the discovery of a brown dwarf orbiting a M1 host star. We first identified the brown dwarf within the Next Generation Transit Survey data, with supporting observations found in TESS sectors 11 and 38. We confirmed the discovery with follow-up photometry from the South African Astronomical Observatory, SPECULOOS-S, and TRAPPIST-S, and radial velocity measurements from HARPS, which allowed us to characterise the system. We find an orbital period of ~1.25 d, a mass of 69.0+5.3-4.8 MJ, close to the Hydrogen burning limit, and a radius of 0.95 +- 0.05 RJ. We determine the age to be >0.5 Gyr, using model isochrones, which is found to be in agreement with SED fitting within errors. NGTS-28Ab is one of the shortest period systems found within the brown dwarf desert, as well as one of the highest mass brown dwarfs that transits an M dwarf. This makes NGTS-28Ab another important discovery within this scarcely populated region., Comment: 20 pages (inc. appendices), 16 figures, accepted for publication in MNRAS

Published
2024

8. 'Someone in Their Corner': Parental Support in Online Secondary Education

Author

Hanny, Courtney N., Graham, Charles R., West, Richard E., and Borup, Jer

Abstract

Despite increased interest in K-12 online education, student engagement deficits and the resulting student attrition remain widespread issues. The Academic Communities of Engagement (ACE) framework theorizes that two groups support online student engagement: the personal community of support and the course community of support. However, more evidence is needed to understand how members of these communities, especially parents, support students in various contexts. Using insights gleaned from 14 semistructured interviews of parents with students enrolled in online secondary school, this study adds support to the roles identified in the ACE framework by presenting real examples of parents supporting their online students' affective, behavioral, and cognitive engagement. Findings also confirm patterns found in previous research that are not explained using the ACE framework, such as parental advocacy, communication with teachers, and self-teaching. We discuss how a systems approach to conceptualizing the ACE communities allows the framework to more accurately capture parents' perceived experiences within the personal community of support. We also discuss implications for both practitioners and members of students' support structures.

Published
2023

9. 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

10. An extended low-density atmosphere around the Jupiter-sized planet WASP-193 b

Author

Barkaoui, Khalid, Pozuelos, Francisco J., Hellier, Coel, Smalley, Barry, Nielsen, Louise D., Niraula, Prajwal, Gillon, Michaël, de Wit, Julien, Müller, Simon, Dorn, Caroline, Helled, Ravit, Jehin, Emmanuel, Demory, Brice-Olivier, Van Grootel, Valerie, Soubkiou, Abderahmane, Ghachoui, Mourad, Anderson, David. R., Benkhaldoun, Zouhair, Bouchy, Francois, Burdanov, Artem, Delrez, Laetitia, Ducrot, Elsa, Garcia, Lionel, Jabiri, Abdelhadi, Lendl, Monika, Maxted, Pierre F. L., Murray, Catriona A., Pedersen, Peter Pihlmann, Queloz, Didier, Sebastian, Daniel, Turner, Oliver, Udry, Stephane, Timmermans, Mathilde, Triaud, Amaury H. M. J., and West, Richard G.

Published
2024
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11. TESS Duotransit Candidates from the Southern Ecliptic Hemisphere

Author

Hawthorn, Faith, Gill, Sam, Bayliss, Daniel, Osborn, Hugh P., Pelisoli, Ingrid, Rodel, Toby, Darnbrook, Kaylen Smith, Wheatley, Peter J., Anderson, David R., Apergis, Ioan nis, Battley, Matthew P., Burleigh, Matthew R., Casewell, Sarah L., Eigmüller, Philipp, Günther, Maximilian N., Jenkins, James S., Lendl, Monika, Moyano, Maximiliano, Osborn, Ares, Ramsay, Gavin, Ulmer-Moll, Solène, Vines, Jose I., and West, Richard

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Discovering transiting exoplanets with long orbital periods allows us to study warm and cool planetary systems with temperatures similar to the planets in our own Solar system. The TESS mission has photometrically surveyed the entire Southern Ecliptic Hemisphere in Cycle 1 (August 2018 - July 2019), Cycle 3 (July 2020 - June 2021) and Cycle 5 (September 2022 - September 2023). We use the observations from Cycle 1 and Cycle 3 to search for exoplanet systems that show a single transit event in each year - which we call duotransits. The periods of these planet candidates are typically in excess of 20 days, with the lower limit determined by the duration of individual TESS observations. We find 85 duotransit candidates, which span a range of host star brightnesses between 8 < $T_{mag}$ < 14, transit depths between 0.1 per cent and 1.8 per cent, and transit durations between 2 and 10 hours with the upper limit determined by our normalisation function. Of these candidates, 25 are already known, and 60 are new. We present these candidates along with the status of photometric and spectroscopic follow-up., Comment: 25 pages, 16 figures, submitted to Monthly Notices of the Royal Astronomical Society

Published
2023

12. Two mini-Neptunes Transiting the Adolescent K-star HIP 113103 Confirmed with TESS and CHEOPS

Author

Lowson, Nataliea, Zhou, George, Huang, Chelsea X., Wright, Duncan J., Edwards, Billy, Nabbie, Emma, Venner, Alex, Quinn, Samuel N., Collins, Karen A., Gillen, Edward, Battley, Matthew, Triaud, Amaury, Hellier, Coel, Seager, Sara, Winn, Joshua N., Jenkins, Jon M., Wohler, Bill, Shporer, Avi, Schwarz, Richard P., Murgas, Felipe, Pallé, Enric, Anderson, David R., West, Richard G., Wittenmyer, Robert A., Bowler, Brendan P., Horner, Jonathan, Kane, Stephen R., Kielkopf, John, Plavchan, Peter, Zhang, Hui, Fairnington, Tyler, Okumura, Jack, Mengel, Matthew W., and Addison, Brett C.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of two mini-Neptunes in near 2:1 resonance orbits ($P=7.610303$ d for HIP 113103 b and $P=14.245651$ d for HIP 113103 c) around the adolescent K-star HIP 113103 (TIC 121490076). The planet system was first identified from the TESS mission, and was confirmed via additional photometric and spectroscopic observations, including a $\sim$17.5 hour observation for the transits of both planets using ESA CHEOPS. We place $\leq4.5$ min and $\leq2.5$ min limits on the absence of transit timing variations over the three year photometric baseline, allowing further constraints on the orbital eccentricities of the system beyond that available from the photometric transit duration alone. With a planetary radius of $R_{p}=1.829^{+0.096}_{-0.067}\,R_{\oplus}$, HIP 113103 b resides within the radius gap, and this might provide invaluable information on the formation disparities between super-Earths and mini-Neptunes. Given the larger radius $R_{p}=2.40^{+0.10}_{-0.08}\,R_{\oplus}$ for HIP 113103 c, and close proximity of both planets to HIP 113103, it is likely that HIP 113103 b might have lost (or is still losing) its primordial atmosphere. We therefore present simulated atmospheric transmission spectra of both planets using JWST, HST, and Twinkle. It demonstrates a potential metallicity difference (due to differences in their evolution) would be a challenge to detect if the atmospheres are in chemical equilibrium. As one of the brightest multi sub-Neptune planet systems suitable for atmosphere follow up, HIP 113103 b and HIP 113103 c could provide insight on planetary evolution for the sub-Neptune K-star population., Comment: 18 pages, 12 figures, published in the Monthly Notices of the Royal Astronomical Society

Published
2023

13. Radar for Europa Assessment and Sounding: Ocean to Near-Surface (REASON)

Author

Blankenship, Donald D., Moussessian, Alina, Chapin, Elaine, Young, Duncan A., Wesley Patterson, G., Plaut, Jeffrey J., Freedman, Adam P., Schroeder, Dustin M., Grima, Cyril, Steinbrügge, Gregor, Soderlund, Krista M., Ray, Trina, Richter, Thomas G., Jones-Wilson, Laura, Wolfenbarger, Natalie S., Scanlan, Kirk M., Gerekos, Christopher, Chan, Kristian, Seker, Ilgin, Haynes, Mark S., Barr Mlinar, Amy C., Bruzzone, Lorenzo, Campbell, Bruce A., Carter, Lynn M., Elachi, Charles, Gim, Yonggyu, Hérique, Alain, Hussmann, Hauke, Kofman, Wlodek, Kurth, William S., Mastrogiuseppe, Marco, McKinnon, William B., Moore, Jeffrey M., Nimmo, Francis, Paty, Carol, Plettemeier, Dirk, Schmidt, Britney E., Zolotov, Mikhail Y., Schenk, Paul M., Collins, Simon, Figueroa, Harry, Fischman, Mark, Tardiff, Eric, Berkun, Andy, Paller, Mimi, Hoffman, James P., Kurum, Andy, Sadowy, Gregory A., Wheeler, Kevin B., Decrossas, Emmanuel, Hussein, Yasser, Jin, Curtis, Boldissar, Frank, Chamberlain, Neil, Hernandez, Brenda, Maghsoudi, Elham, Mihaly, Jonathan, Worel, Shana, Singh, Vik, Pak, Kyung, Tanabe, Jordan, Johnson, Robert, Ashtijou, Mohammad, Alemu, Tafesse, Burke, Michael, Custodero, Brian, Tope, Michael C., Hawkins, David, Aaron, Kim, Delory, Gregory T., Turin, Paul S., Kirchner, Donald L., Srinivasan, Karthik, Xie, Julie, Ortloff, Brad, Tan, Ian, Noh, Tim, Clark, Duane, Duong, Vu, Joshi, Shivani, Lee, Jeng, Merida, Elvis, Akbar, Ruzbeh, Duan, Xueyang, Fenni, Ines, Sanchez-Barbetty, Mauricio, Parashare, Chaitali, Howard, Duane C., Newman, Julie, Cruz, Marvin G., Barabas, Neil J., Amirahmadi, Ahmadreza, Palmer, Brendon, Gawande, Rohit S., Milroy, Grace, Roberti, Rick, Leader, Frank E., West, Richard D., Martin, Jan, Venkatesh, Vijay, Adumitroaie, Virgil, Rains, Christine, Quach, Cuong, Turner, Jordi E., O’Shea, Colleen M., Kempf, Scott D., Ng, Gregory, Buhl, Dillon P., and Urban, Timothy J.

Published
2024
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14. Utah

Author

Campbell, Kim, Charlton, Cade, Maynes, John, and West, Richard

Published
2014

15. An extended low-density atmosphere around the Jupiter-sized planet WASP-193 b

Author

Barkaoui, Khalid, Pozuelos, Francisco J., Hellier, Coel, Smalley, Barry, Nielsen, Louise D., Niraula, Prajwal, Gillon, Michaël, de Wit, Julien, Müller, Simon, Dorn, Caroline, Helled, Ravit, Jehin, Emmanuel, Demory, Brice-Olivier, Van Grootel, V., Soubkiou, Abderahmane, Ghachoui, Mourad, Anderson, David. R., Benkhaldoun, Zouhair, Bouchy, Francois, Burdanov, Artem, Delrez, Laetitia, Ducrot, Elsa, Garcia, Lionel, Jabiri, Abdelhadi, Lendl, Monika, Maxted, Pierre F. L., Murray, Catriona A., Pedersen, Peter Pihlmann, Queloz, Didier, Sebastian, Daniel, Turner, Oliver, Udry, Stephane, Timmermans, Mathilde, Triaud, Amaury H. M. J., and West, Richard G.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Gas giants transiting bright nearby stars provide crucial insights into planetary system formation and evolution mechanisms. Most of these planets exhibit certain average characteristics, serving as benchmarks for our understanding of planetary systems. However, outliers like the planet we present in this study, WASP-193b, offer unique opportunities to explore unconventional formation and evolution processes. This planet completes an orbit around its Vmag=12.2 F9 main-sequence host star every 6.25 d. Our analyses found that WASP-193b has a mass of Mp=0.139+/-0.029 MJup and a radius of Rp=1.464+/-0.058 RJup, translating into an extremely low density of rho_p = 0.059+/-0.014 g/cm^3, at least one order of magnitude less than standard gas giants like Jupiter. Typical gas giants such as Jupiter have densities that range between 0.2 and 2 g/cm^3. The combination of its large transit depth (dF~1.4%), its extremely-low density, its high-equilibrium temperature (Teq = 1254+/-31 K), and the infrared brightness of its host star (magnitude Kmag=10.7) makes WASP-193b an exquisite target for characterization by transmission spectroscopy (transmission spectroscopy metric: TSM~600). One single JWST transit observation would yield detailed insights into its atmospheric properties and planetary mass, providing a unique window to explore the mechanisms behind its exceptionally low density and shed light on giant planets' diverse nature., Comment: 10 figures and 35 pages

Published
2023
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16. NGTS clusters survey $-$ V: Rotation in the Orion Star-forming Complex

Author

Smith, Gareth D., Gillen, Edward, Hodgkin, Simon T., Alves, Douglas R., Anderson, David R., Battley, Matthew P., Burleigh, Matthew R., Casewell, Sarah L., Gill, Samuel, Goad, Michael R., Henderson, Beth A., Jenkins, James S., Kendall, Alicia, Moyano, Maximiliano, Ramsay, Gavin, Tilbrook, Rosanna H., Vines, Jose I., West, Richard G., and Wheatley, Peter J.

Subjects
Astrophysics - Solar and Stellar Astrophysics, Astrophysics - Astrophysics of Galaxies
Abstract

We present a study of rotation across 30 square degrees of the Orion Star-forming Complex, following a $\sim$200 d photometric monitoring campaign by the Next Generation Transit Survey (NGTS). From 5749 light curves of Orion members, we report periodic signatures for 2268 objects and analyse rotation period distributions as a function of colour for 1789 stars with spectral types F0$-$M5. We select candidate members of Orion using $\textit{Gaia}$ data and assign our targets to kinematic sub-groups. We correct for interstellar extinction on a star-by-star basis and determine stellar and cluster ages using magnetic and non-magnetic stellar evolutionary models. Rotation periods generally lie in the range 1$-$10 d, with only 1.5 per cent of classical T Tauri stars or Class I/II young stellar objects rotating with periods shorter than 1.8 d, compared with 14 per cent of weak-line T Tauri stars or Class III objects. In period$-$colour space, the rotation period distribution moves towards shorter periods among low-mass (>M2) stars of age 3$-$6 Myr, compared with those at 1$-$3 Myr, with no periods longer than 10 d for stars later than M3.5. This could reflect a mass-dependence for the dispersal of circumstellar discs. Finally, we suggest that the turnover (from increasing to decreasing periods) in the period$-$colour distributions may occur at lower mass for the older-aged population: $\sim$K5 spectral type at 1$-$3 Myr shifting to $\sim$M1 at 3$-$6 Myr., Comment: This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. Published by Oxford University Press on behalf of the Royal Astronomical Society. 20 pages. 21 figures

Published
2023
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17. Simulated recovery of LEO objects using sCMOS blind stacking

Author

Cooke, Benjamin F., Chote, Paul, Pollacco, Don, West, Richard, Blake, James A., McCormac, James, Airey, Robert, and Shrive, Billy

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

We present the methodology and results of a simulation to determine the recoverability of LEO objects using a blind stacking technique. The method utilises sCMOS and GPU technology to inject and recover LEO objects in real observed data. We explore the target recovery fraction and pipeline run-time as a function of three optimisation parameters; number of frames per data-set, exposure time, and binning factor. Results are presented as a function of magnitude and velocity. We find that target recovery using blind stacking is significantly more complete, and can reach fainter magnitudes, than using individual frames alone. We present results showing that, depending on the combination of optimisation parameters, recovery fraction is up to 90% of detectable targets for magnitudes up to 13.5, and then falls off steadily up to a magnitude limit around 14.5. Run-time is shown to be a few multiples of the observing time for the best combinations of optimisation parameters, approaching real-time processing., Comment: 14 pages, 14 figures. Accepted for publication in Advances in Space Research (ASR)

Published
2023

25. A Recent History of Learning Design and Technology

Author

Ramsey, Jennifer L. and West, Richard E.

Abstract

The history of the learning design and technology field for the length of the twentieth century is well documented, however, events after the year 2000, even our lived histories, are missing from important timelines and discussions. This article is an attempt to describe the history of events in the educational technology and research field from the start of the twenty-first century to the global COVD-19 Pandemic. This historical overview reflects on these events and their significance to the field's identity and future.

Published
2023
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28. Faculty Perceptions of Using Synchronous Video-Based Communication Technology

Author

Lowenthal, Patrick R., West, Richard E., Archambault, Leanna, Borup, Jer, and Belt, Eric S.

Abstract

Online learning has traditionally relied on asynchronous text-based communication. The COVID-19 pandemic, though, has provided many faculty members with new and/or additional experience using synchronous video-based communication. Questions remain, though, about how this experience will shape online teaching and learning in the future. We conducted a mixed method study to investigate faculty perceptions of using synchronous video-based communication technology. In this paper, we present the results of our inquiry and implications for future research and practice.

Published
2021

29. 'We Overwhelm Them with Hope': How Online Mentors Can Support Online Learners

Author

Andersen, Camey L. and West, Richard E.

Abstract

This survey research study analyzed responses from 143 mentors from around the world participating in a global higher education initiative. Results confirmed the effectiveness of four mentoring domains identified in the literature, reporting the most success from providing emotional and psychological support for students. This article provides mentoring strategies including student goal setting, identifies characteristics of an online role model, and shows the importance of online mentors' confidence in students gaining technology skills. The study has additionally contributed to the literature supporting (a) benefits of online mentoring for nontraditional students, (b) influence of technology on mentoring challenges, and (c) role assumption in online mentoring. Additionally, the study provided a literature review of the background of online mentoring and mentoring practices, the benefits and challenges of online mentoring, and lessons learned from research. This work presents a comprehensive understanding of online mentoring, providing support for mentors seeking to improve their performance as well as recommendations for creating mentoring programs to improve organizations.

Published
2021

30. A DPU Solution for Container Overlay Networks

Author

Njavro, Anton, Tau, James, Groves, Taylor, Wright, Nicholas J., and West, Richard

Subjects
Computer Science - Distributed, Parallel, and Cluster Computing, Computer Science - Networking and Internet Architecture
Abstract

There is an increasing demand to incorporate hybrid environments as part of workflows across edge, cloud, and HPC systems. In a such converging environment of cloud and HPC, containers are starting to play a more prominent role, bringing their networking infrastructure along with them. However, the current body of work shows that container overlay networks, which are often used to connect containers across physical hosts, are ill-suited for the HPC environment. They tend to impose significant overhead and noise, resulting in degraded performance and disturbance to co-processes on the same host. This paper focuses on utilizing a novel class of hardware, Data Processing Unit, to offload the networking stack of overlay networks away from the host onto the DPU. We intend to show that such ancillary offload is possible and that it will result in decreased overhead on host nodes which in turn will improve the performance of running processes., Comment: Pre-print version presented at SuperCompCloud workshop at SC22 conference

Published
2022

31. The discovery of three hot Jupiters, NGTS-23b, 24b and 25b, and updated parameters for HATS-54b from the Next Generation Transit Survey

Author

Jackson, David G., Watson, Christopher A., de Mooij, Ernst J. W., Acton, Jack S., Alves, Douglas R., Anderson, David R., Armstrong, David J., Bayliss, Daniel, Belardi, Claudia, Bouchy, François, Bryant, Edward M., Burleigh, Matthew R., Casewell, Sarah L., Costes, Jean C., Eigmüller, Phillip, Goad, Michael R., Gill, Samuel, Gillen, Edward, Günther, Maximilian N., Hawthorn, Faith, Henderson, Beth A., Jackman, James A. G., Jenkins, James S., Lendl, Monika, Kendall, Alicia, McCormac, James, Moyano, Maximiliano, Nielsen, Louise. D., Osborn, Ares, Sefako, Ramotholo R., Smith, Alexis M. S., Tilbrook, Rosanna H., Turner, Oliver, Udry, Stéphane, Vines, Jose I., West, Richard G., Wheatley, Peter J., and Worters, Hannah

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of three new hot Jupiters with the Next Generation Transit Survey (NGTS) as well as updated parameters for HATS-54b, which was independently discovered by NGTS. NGTS-23b, NGTS-24b and NGTS-25b have orbital periods of 4.076, 3.468, and 2.823 days and orbit G-, F- and K-type stars, respectively. NGTS-24 and HATS-54 appear close to transitioning off the main-sequence (if they are not already doing so), and therefore are interesting targets given the observed lack of Hot Jupiters around sub-giant stars. By considering the host star luminosities and the planets' small orbital separations (0.037 - 0.050 au), we find that all four hot Jupiters are above the minimum irradiance threshold for inflation mechanisms to be effective. NGTS-23b has a mass of 0.61 $M_{J}$ and radius of 1.27 $R_{J}$ and is likely inflated. With a radius of 1.21 $R_{J}$ and mass of 0.52 $M_{J}$, NGTS-24b has a radius larger than expected from non-inflated models but its radius is smaller than the predicted radius from current Bayesian inflationary models. Finally, NGTS-25b is intermediate between the inflated and non-inflated cases, having a mass of 0.64 $M_{J}$ and a radius of 1.02 $R_{J}$. The physical processes driving radius inflation remain poorly understood, and by building the sample of hot Jupiters we can aim to identify the additional controlling parameters, such as metallicity and stellar age., Comment: 17 pages, 8 figures. Accepted for publication in MNRAS

Published
2022
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33. The TESS Grand Unified Hot Jupiter Survey. II. Twenty New Giant Planets

Author

Yee, Samuel W., Winn, Joshua N., Hartman, Joel D., Bouma, Luke G., Zhou, George, Quinn, Samuel N., Latham, David W., Bieryla, Allyson, Rodriguez, Joseph E., Collins, Karen A., Alfaro, Owen, Barkaoui, Khalid, Beard, Corey, Belinski, Alexander A., Benkhaldoun, Zouhair, Benni, Paul, Bernacki, Krzysztof, Boyle, Andrew W., Butler, R. Paul, Caldwell, Douglas A., Chontos, Ashley, Christiansen, Jessie L., Ciardi, David R., Collins, Kevin I., Conti, Dennis M., Crane, Jeffrey D., Daylan, Tansu, Dressing, Courtney D., Eastman, Jason D., Essack, Zahra, Evans, Phil, Everett, Mark E., Fajardo-Acosta, Sergio, Forés-Toribio, Raquel, Furlan, Elise, Ghachoui, Mourad, Gillon, Michaël, Hellier, Coel, Helm, Ian, Howard, Andrew W., Howell, Steve B., Isaacson, Howard, Jehin, Emmanuel, Jenkins, Jon M., Jensen, Eric L. N., Kielkopf, John F., Laloum, Didier, Leonhardes-Barboza, Naunet, Logsdon, Sarah E., Lubin, Jack, Lund, Michael B., MacDougall, Mason G., Mann, Andrew W., Maslennikova, Natalia A., Massey, Bob, McLeod, Kim K., Muñoz, Jose A., Newman, Patrick, Orlov, Valeri, Plavchan, Peter, Popowicz, Adam, Pozuelos, Francisco J., Pritchard, Tyler A., Radford, Don J., Reefe, Michael, Ricker, George R., Rudat, Alexander, Safonov, Boris S., Schwarz, Richard P., Schweiker, Heidi, Scott, Nicholas J., Seager, S., Shectman, Stephen A., Stockdale, Chris, Tan, Thiam-Guan, Teske, Johanna K., Thomas, Neil B., Timmermans, Mathilde, Vanderspek, Roland, Vermilion, David, Watanabe, David, Weiss, Lauren M., West, Richard G., Van Zandt, Judah, Zejmo, Michal, and Ziegler, Carl

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

NASA's Transiting Exoplanet Survey Satellite (TESS) mission promises to improve our understanding of hot Jupiters by providing an all-sky, magnitude-limited sample of transiting hot Jupiters suitable for population studies. Assembling such a sample requires confirming hundreds of planet candidates with additional follow-up observations. Here, we present twenty hot Jupiters that were detected using TESS data and confirmed to be planets through photometric, spectroscopic, and imaging observations coordinated by the TESS Follow-up Observing Program (TFOP). These twenty planets have orbital periods shorter than 7 days and orbit relatively bright FGK stars ($10.9 < G < 13.0$). Most of the planets are comparable in mass to Jupiter, although there are four planets with masses less than that of Saturn. TOI-3976 b, the longest period planet in our sample ($P = 6.6$ days), may be on a moderately eccentric orbit ($e = 0.18\pm0.06$), while observations of the other targets are consistent with them being on circular orbits. We measured the projected stellar obliquity of TOI-1937A b, a hot Jupiter on a 22.4 hour orbit with the Rossiter-McLaughlin effect, finding the planet's orbit to be well-aligned with the stellar spin axis ($|\lambda| = 4.0\pm3.5^\circ$). We also investigated the possibility that TOI-1937 is a member of the NGC 2516 open cluster, but ultimately found the evidence for cluster membership to be ambiguous. These objects are part of a larger effort to build a complete sample of hot Jupiters to be used for future demographic and detailed characterization work., Comment: 67 pages, 11 tables, 13 figures, 2 figure sets. Resubmitted to ApJS after revisions

Published
2022
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34. A sub-Neptune transiting the young field star HD 18599 at 40 pc

Author

de Leon, Jerome P., Livingston, John H., Jenkins, James S., Vines, Jose I., Wittenmyer, Robert A., Clark, Jake T., Winn, Joshua I. M., Addison, Brett, Ballard, Sarah, Bayliss, Daniel, Beichman, Charles, Benneke, Björn, Berardo, David Anthony, Bowler, Brendan P., Brown, Tim, Bryant, Edward M., Christiansen, Jessie, Ciardi, David, Collins, Karen A., Collins, Kevin I., Crossfield, Ian, Deming, Drake, Dragomir, Diana, Dressing, Courtney D., Fukui, Akihiko, Gan, Tianjun, Giacalone, Steven, Gill, Samuel, Alvarez, Erica Gonz\' alez, Hesse, Katharine, Horner, Jonathan, Howell, Steve B., Jenkins, Jon M., Kane, Stephen R., Kendall, Alicia, Kielkopf, John F., Kreidberg, Laura, Latham, David W., Liu, Huigen, Lund, Michael B., Matson, Rachel, Matthews, Elisabeth, Mengel, Matthew W., Morales, Farisa, Mori, Mayuko, Narita, Norio, Nishiumi, Taku, Okumura, Jack, Plavchan, Peter, Quinn, Sam, Rabus, Markus, Ricker, George, Rudat, Alexander, Schlieder, Joshua, Schwarz, Richard P., Seager, Sara, Shporer, Avi, Smith, Alexis M. S., Sphorer, Avi, Stassun, Keivan, Tamura, Motohide, Tan, Thiam Guan, Tinney, C. G., Vanderspek, Roland, Gorjian, Varoujan, Werner, Michael W., West, Richard G., Wright, Duncan, Zhang, Hui, and Zhou, George

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Transiting exoplanets orbiting young nearby stars are ideal laboratories for testing theories of planet formation and evolution. However, to date only a handful of stars with age <1 Gyr have been found to host transiting exoplanets. Here we present the discovery and validation of a sub-Neptune around HD 18599, a young (300 Myr), nearby (d=40 pc) K star. We validate the transiting planet candidate as a bona fide planet using data from the TESS, Spitzer, and Gaia missions, ground-based photometry from IRSF, LCO, PEST, and NGTS, speckle imaging from Gemini, and spectroscopy from CHIRON, NRES, FEROS, and Minerva-Australis. The planet has an orbital period of 4.13 d, and a radius of 2.7Rearth. The RV data yields a 3-sigma mass upper limit of 30.5Mearth which is explained by either a massive companion or the large observed jitter typical for a young star. The brightness of the host star (V~9 mag) makes it conducive to detailed characterization via Doppler mass measurement which will provide a rare view into the interior structure of young planets., Comment: submitted to MNRAS

Published
2022
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35. NGTS-21b: An Inflated Super-Jupiter Orbiting a Metal-poor K dwarf

Author

Alves, Douglas R., Jenkins, James S., Vines, Jose I., Nielsen, Louise D., Gill, Samuel, Acton, Jack S., Anderson, D. R., Bayliss, Daniel, Bouchy, François, Breytenbach, Hannes, Bryant, Edward M., Burleigh, Matthew R., Casewell, Sarah L., Eigmüller, Philipp, Gillen, Edward, Goad, Michael R., Günther, Maximilian N., Henderson, Beth A., Kendall, Alicia, Lendl, Monika, Moyano, Maximiliano, Sefako, Ramotholo R., Smith, Alexis M. S., Costes, Jean C., Tilbrook, Rosanne H., Thomas, Jessymol K., Udry, Stéphane, Watson, Christopher A., West, Richard G., Wheatley, Peter J., Worters, Hannah L., and Osborn, Ares

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of NGTS-21b, a massive hot Jupiter orbiting a low-mass star as part of the Next Generation Transit Survey (NGTS). The planet has a mass and radius of $2.36 \pm 0.21$ M$_{\rm J}$, and $1.33 \pm 0.03$ R$_{\rm J}$, and an orbital period of 1.543 days. The host is a K3V ($T_{\rm eff}=4660 \pm 41$, K) metal-poor (${\rm [Fe/H]}=-0.26 \pm 0.07$, dex) dwarf star with a mass and radius of $0.72 \pm 0.04$, M$_{\odot}$,and $0.86 \pm 0.04$, R$_{\odot}$. Its age and rotation period of $10.02^{+3.29}_{-7.30}$, Gyr and $17.88 \pm 0.08$, d respectively, are in accordance with the observed moderately low stellar activity level. When comparing NGTS-21b with currently known transiting hot Jupiters with similar equilibrium temperatures, it is found to have one of the largest measured radii despite its large mass. Inflation-free planetary structure models suggest the planet's atmosphere is inflated by $\sim21\%$, while inflationary models predict a radius consistent with observations, thus pointing to stellar irradiation as the probable origin of NGTS-21b's radius inflation. Additionally, NGTS-21b's bulk density ($1.25 \pm 0.15$, g/cm$^3$) is also amongst the largest within the population of metal-poor giant hosts ([Fe/H] < 0.0), helping to reveal a falling upper boundary in metallicity-planet density parameter space that is in concordance with core accretion formation models. The discovery of rare planetary systems such as NGTS-21 greatly contributes towards better constraints being placed on the formation and evolution mechanisms of massive planets orbiting low-mass stars., Comment: 12 pages, 13 figures, accepted for publication in MNRAS

Published
2022
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36. An old warm Jupiter orbiting the metal-poor G-dwarf TOI-5542

Author

Grieves, Nolan, Bouchy, François, Ulmer-Moll, Solène, Gill, Samuel, Anderson, David R., Psaridi, Angelica, Lendl, Monika, Stassun, Keivan G., Jenkins, Jon M., Burleigh, Matthew R., Acton, Jack S., Boyd, Patricia T., Casewell, Sarah L., Eigmüller, Philipp, Goad, Michael R., Goeke, Robert F., Günther, Maximilian N., Hawthorn, Faith, Henderson, Beth A., Henze, Christopher E., Jordán, Andrés, Kendall, Alicia, Mishra, Lokesh, Moldovan, Dan, Moyano, Maximiliano, Osborn, Hugh, Revol, Alexandre, Sefako, Ramotholo R., Tilbrook, Rosanna H., Udry, Stéphane, Unger, Nicolas, Vines, Jose I., West, Richard G., and Worters, Hannah L.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of a 1.32$^{+0.10}_{-0.10}$ $\mathrm{M_{\rm Jup}}$ planet orbiting on a 75.12 day period around the G3V $10.8^{+2.1}_{-3.6}$ Gyr old star TOI-5542 (TIC 466206508; TYC 9086-1210-1). The planet was first detected by the Transiting Exoplanet Survey Satellite (TESS) as a single transit event in TESS Sector 13. A second transit was observed 376 days later in TESS Sector 27. The planetary nature of the object has been confirmed by ground-based spectroscopic and radial velocity observations from the CORALIE and HARPS spectrographs. A third transit event was detected by the ground-based facilities NGTS, EulerCam, and SAAO. We find the planet has a radius of 1.009$^{+0.036}_{-0.035}$ $\mathrm{R_{\rm Jup}}$ and an insolation of 9.6$^{+0.9}_{-0.8}$ $S_{\oplus}$, along with a circular orbit that most likely formed via disk migration or in situ formation, rather than high-eccentricity migration mechanisms. Our analysis of the HARPS spectra yields a host star metallicity of [Fe/H] = $-$0.21$\pm$0.08, which does not follow the traditional trend of high host star metallicity for giant planets and does not bolster studies suggesting a difference among low- and high-mass giant planet host star metallicities. Additionally, when analyzing a sample of 216 well-characterized giant planets, we find that both high masses (4 $\mathrm{M_{\rm Jup}}$ $$ 10 days) and hot (P $<$ 10 days) giant planets are preferentially located around metal-rich stars (mean [Fe/H] $>$ 0.1). TOI-5542b is one of the oldest known warm Jupiters and it is cool enough to be unaffected by inflation due to stellar incident flux, making it a valuable contribution in the context of planetary composition and formation studies., Comment: 16 pages, 12 figures, Accepted by Astronomy & Astrophysics September 19, 2022

Published
2022
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39. Periodic stellar variability from almost a million NGTS light curves

Author

Briegal, Joshua T., Gillen, Edward, Queloz, Didier, Hodgkin, Simon, Acton, Jack S., Anderson, David R., Armstrong, David J., Battley, Matthew P., Bayliss, Daniel, Burleigh, Matthew R., Bryant, Edward M., Casewell, Sarah L., Costes, Jean C., Eigmuller, Philipp, Gill, Samuel, Goad, Michael R., Gunther, Maximilian N., Henderson, Beth A., Jackman, James A. G., Jenkins, James S., Kreutzer, Lars T., Moyano, Maximiliano, Lendl, Monika, Smith, Gareth D., Tilbrook, Rosanna H., Watson, Christopher A., West, Richard G., and Wheatley, Peter J.

Subjects
Astrophysics - Solar and Stellar Astrophysics
Abstract

We analyse 829,481 stars from the Next Generation Transit Survey (NGTS) to extract variability periods. We utilise a generalisation of the autocorrelation function (the G-ACF), which applies to irregularly sampled time series data. We extract variability periods for 16,880 stars from late-A through to mid-M spectral types and periods between 0.1 and 130 days with no assumed variability model. We find variable signals associated with a number of astrophysical phenomena, including stellar rotation, pulsations and multiple-star systems. The extracted variability periods are compared with stellar parameters taken from Gaia DR2, which allows us to identify distinct regions of variability in the Hertzsprung-Russell Diagram. We explore a sample of rotational main-sequence objects in period-colour space, in which we observe a dearth of rotation periods between 15 and 25 days. This 'bi-modality' was previously only seen in space-based data. We demonstrate that stars in sub-samples above and below the period gap appear to arise from a stellar population not significantly contaminated by excess multiple systems. We also observe a small population of long-period variable M-dwarfs, which highlight a departure from the predictions made by rotational evolution models fitted to solar-type main-sequence objects. The NGTS data spans a period and spectral type range that links previous rotation studies such as those using data from Kepler, K2 and MEarth., Comment: 22 pages, 13 figures, 3 tables. Accepted for publication in MNRAS

Published
2022
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41. TIC-320687387 B: a long-period eclipsing M-dwarf close to the hydrogen burning limit

Author

Gill, Samuel, Ulmer-Moll, Solene, Wheatley, Peter J., Bayliss, Daniel, Burleigh, Matthew R., Acton, Jack S., Casewell, Sarah L., Watson, Christopher A., Lendl, Monika, Worters, Hannah L., Sefako, Ramotholo R., Anderson, David R., Alves, Douglas R., Bouchy, François, Bryant, Edward M., Eigmüller, Philipp, Gillen, Edward, Goad, Michael R., Grieves, Nolan, Günther, Maximilian N., Henderson, Beth A., Jenkins, James S., Mishra, Lokesh, Moyano, Maximiliano, Osborn, Hugh P., Tilbrook, Rosanna H., Udry, Stéphane, Vines, Jose I., and West, Richard G.

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

We are using precise radial velocities from CORALIE together with precision photometry from the Next Generation Transit Survey (NGTS) to follow up stars with single-transit events detected with the Transiting Exoplanet Survey Satellite (TESS). As part of this survey we identified a single transit on the star TIC-320687387, a bright (T=11.6) G-dwarf observed by TESS in Sector 13 and 27. From subsequent monitoring of TIC-320687387 with CORALIE, NGTS, and Lesedi we determined that the companion, TIC-320687387 B,is a very low-mass star with a mass of $96.2 \pm _{2.0}^{1.9} M_J$ and radius of $1.14 \pm _{0.02}^{0.02} R_J$ placing it close to the hydrogen burning limit ($\sim 80 M_J$). TIC-320687387 B has a wide and eccentric orbit, with a period of 29.77381 days and an eccentricity of $0.366 \pm 0.003$. Eclipsing systems such as TIC-320687387 AB allow us to test stellar evolution models for low-mass stars, which in turn are needed to calculate accurate masses and radii for exoplanets orbiting single low-mass stars. The wide orbit of TIC-320687387 B makes it particularly valuable as its evolution can be assumed to be free from perturbations caused by tidal interactions with its G-type host star., Comment: 9 pages, 6 figures, 4 tables. Submitted to MNRAS

Published
2022
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43. Scintillation-limited photometry with the 20-cm NGTS telescopes at Paranal Observatory

Author

O'Brien, Sean M., Bayliss, Daniel, Osborn, James, Bryant, Edward M., McCormac, James, Wheatley, Peter J., Acton, Jack S., Alves, Douglas R., Anderson, David R., Burleigh, Matthew R., Casewell, Sarah L., Gill, Samuel, Goad, Michael R., Henderson, Beth A., Jackman, James A. G., Lendl, Monika, Tilbrook, Rosanna H., Udry, Stéphane, Vines, Jose I., and West, Richard G.

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

Ground-based photometry of bright stars is expected to be limited by atmospheric scintillation, although in practice observations are often limited by other sources of systematic noise. We analyse 122 nights of bright star ($G_{mag} < 11.5$) photometry using the 20-cm telescopes of the Next-Generation Transit Survey (NGTS) at the Paranal Observatory in Chile. We compare the noise properties to theoretical noise models and we demonstrate that NGTS photometry of bright stars is indeed limited by atmospheric scintillation. We determine a median scintillation coefficient at the Paranal Observatory of $C_Y = 1.54$, which is in good agreement with previous results derived from turbulence profiling measurements at the observatory. We find that separate NGTS telescopes make consistent measurements of scintillation when simultaneously monitoring the same field. Using contemporaneous meteorological data, we find that higher wind speeds at the tropopause correlate with a decrease in long-exposure ($t=10$ s) scintillation. Hence the winter months between June and August provide the best conditions for high precision photometry of bright stars at the Paranal Observatory. This work demonstrates that NGTS photometric data, collected for searching for exoplanets, contains within it a record of the scintillation conditions at Paranal., Comment: 8 pages, 7 figures. Accepted for publication in MNRAS

Published
2021
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45. Bridging Academic Disciplines with Interdisciplinary Project-Based Learning: Challenges and Opportunities

Author

Warr, Melissa and West, Richard E.

Abstract

This article describes the implementation of an interdisciplinary design studio as a means to teach creative problem-solving through project-based learning. "Learning and Innovation Skills" has been designated as a core skill that students need to be successful in today's world, and project-based learning is one approach to helping students develop these skills. After describing the early genesis and development of the interdisciplinary design studio, the article describes results of initial research into the students' experiences in studio courses. Students described courses as flexible and reported high levels of motivation stemming from the authenticity of the problems. Because of the interdisciplinary nature of the studio, some students described deepening disciplinary skills while at the same time being exposed to cross-disciplinary skills. They believed the courses helped develop interdisciplinary collaboration, creativity, and communication skills.

Published
2020
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46. Getting Started with Open Badges and Open Microcredentials

Author

Clements, Kyle, West, Richard E., and Hunsaker, Enoch

Abstract

This article is intended as a practical resource to help interested organizations design and implement an open badging system. Open badges are a type of open credential designed to recognize a variety of skills, knowledge, and experiences, both inside and outside of traditional educational settings. While growing in popularity, common questions asked by those interested in using open badges include: How do I get started? What technologies exist to produce open badges? And what do I need to know? This article seeks to address questions such as these. First, we introduce the reader to key terms in the badging world and explore open badge design precedents, responding to who, what, how, where, and why open badges have been used in the past. Drawing on this research as well as our own personal experience, we then present a possible framework for getting started with open badges and a step-by-step guide for implementing that framework within your organization.

Published
2020

47. Open Badges for Employee Skill Tracking

Author

Clements, Kyle, Jackson, Sam, and West, Richard E

Abstract

This case explores the creation of an open badge student-employee training program. Utilizing competency-based learning, we created nearly 40 digital credentials for technical skills related to various software products. We specifically share the decisions we made related to the process of defining competencies, formatting badge criteria, and building a flexible learning system. We also discuss various challenges, including how we motivated employees to participate in the program and unforeseen challenges related to selecting a badge issuing tool.

Published
2020

50. Value of Open Microcredentials to Earners and Issuers: A Case Study of National Instruments Open Badges

Author

Young, Danny, West, Richard E., and Nylin, Travis Ann

Abstract

While microcredentials and open digital badges have become increasingly popular in education, more research is needed to better understand their implementation and benefits to both issuers and users. In this paper, we use a case study approach to report and discuss the outcomes from the implementation of an open badges program at National Instruments, highlighting the effects this program has had on both National Instruments and its users. As the program evolves to better meet the needs of its stakeholders, we find that both participants (badge earners) and the issuer (National Instruments) see potential value in the National Instruments Badging Program. The value for both seems to stem from the way in which the program enables the sharing of badges, which helps the earner establish their skills/reputation while also increasing awareness of the program for National Instruments. This study adds to our understanding of why an organization may find value in offering open microcredentials as an alternative to traditional professional development and certificates for their customers and employees.

Published
2019

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