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2. Coronary Disease in Emergency Department Chest Pain Patients with Recent Negative Stress Testing

Author

Walker, Jonathan, Galuska, Michael, and Vega, David

Subjects
Chest pain, cardiac stress test, Medicine, Medical emergencies. Critical care. Intensive care. First aid, RC86-88.9
Abstract

Background: Cardiac stress tests for diagnosis of coronary artery disease (CAD) are incompletely sensitive and specific.Objective: We examined the frequency of significant CAD in patients presenting to the emergency department (ED) with chest pain who have had a recent negative or inconclusive (

Published
2010

20. An Optical/near-infrared investigation of HD 100546 b with the Gemini Planet Imager and MagAO

Author

Rameau, Julien, Follette, Katherine B., Pueyo, Laurent, Marois, Christian, Macintosh, Bruce, Millar-Blanchaer, Maxwell, Wang, Jason J., Vega, David, Doyon, Rene, Lafreniere, David, Nielsen, Eric L., Bailey, Vanessa, Chilcote, Jeffrey K., Close, Laird M., Esposito, Thomas M., Males, Jared R., Metchev, Stanimir, Morzinski, Katie M., Ruffio, Jean-Baptiste, Wolff, Schuyler G., Ammons, S. M., Barman, Travis S., Bulger, Joanna, Cotten, Tara, De Rosa, Robert J., Duchene, Gaspard, Fitzgerald, Michael P., Goodsell, Stephen, Graham, James R., Greenbaum, Alexandra Z., Hibon, Pascale, Hung, Li-Wei, Ingraham, Patrick, Kalas, Paul, Konopacky, Quinn, Larkin, James E., Maire, Jerome, Marchis, Franck, Marley, Mark S., Oppenheimer, Rebecca, Palmer, David, Patience, Jennifer, Perrin, Marshall D., Poyneer, Lisa, Rajan, Abhijith, Rantakyro, Fredrik T., Savransky, Dmitry, Schneider, Adam C., Sivaramakrishnan, Anand, Song, Inseok, Soummer, Remi, Thomas, Sandrine, Wallace, J. Kent, Ward-Duong, Kimberly, and Wiktorowicz, Sloane

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We present H band spectroscopic and Halpha photometric observations of HD 100546 obtained with GPI and MagAO. We detect H band emission at the location of the protoplanet HD 100546b, but show that choice of data processing parameters strongly affects the morphology of this source. It appears point-like in some aggressive reductions, but rejoins an extended disk structure in the majority of the others. Furthermore, we demonstrate that this emission appears stationary on a timescale of 4.6 yrs, inconsistent at the 2sigma level with a Keplerian clockwise orbit at 59 au in the disk plane. The H band spectrum of the emission is inconsistent with any type of low effective temperature object or accreting protoplanetary disk. It strongly suggests a scattered light origin, as it is consistent with the spectrum of the star and the spectra extracted at other locations in the disk. A non detection at the 5sigma level of HD 100546b in differential Halpha imaging places an upper limit, assuming the protoplanet lies in a gap free of extinction, on the accretion luminosity and accretion rate of 1.7E-4 Lsun and MMdot<6.4E-7Mjup^2/yr for 1Rjup. These limits are comparable to the accretion luminosity and rate of TTauri-stars or LkCa 15b. Taken together, these lines of evidence suggest that the H band source at the location of HD 100546b is not emitted by a planetary photosphere or an accreting circumplanetary disk but is a disk feature enhanced by the PSF subtraction process. This non-detection is consistent with the non-detection in the K band reported in an earlier study but does not exclude the possibility that HD 100546b is deeply embedded., Comment: Accepted to AJ, 10 pages, 6 figures, 1 table

Published
2017
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21. Complex Spiral Structure in the HD 100546 Transitional Disk as Revealed by GPI and MagAO

Author

Follette, Katherine B., Rameau, Julien, Dong, Ruobing, Pueyo, Laurent, Close, Laird M., Duchene, Gaspard, Fung, Jeffrey, Leonard, Clare, Macintosh, Bruce, Males, Jared R., Marois, Christian, Millar-Blanchaer, Maxwell A., Morzinski, Katie M., Mullen, Wyatt, Perrin, Marshall, Spiro, Elijah, Wang, Jason, Ammons, S. Mark, Bailey, Vanessa P., Barman, Travis, Bulger, Joanna, Chilcote, Jeffrey, Cotten, Tara, De Rosa, Robert J., Doyon, Rene, Fitzgerald, Michael P., Goodsell, Stephen J., Graham, James R., Greenbaum, Alexandra Z., Hibon, Pascale, Hung, Li-Wei, Ingraham, Patrick, Kalas, Paul, Konopacky, Quinn, Larkin, James E., Maire, Jerome, Marchis, Franck, Metchev, Stanimir, Nielsen, Eric L., Oppenheimer, Rebecca, Palmer, David, Patience, Jennifer, Poyneer, Lisa, Rajan, Abhijith, Rantakyro, Fredrik T., Savransky, Dmitry, Schneider, Adam C., Sivaramakrishnan, Anand, Song, Inseok, Soummer, Remi, Thomas, Sandrine, Vega, David, Wallace, J. Kent, Ward-Duong, Kimberly, Wiktorowicz, Sloane, and Wolff, Schuyler

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We present optical and near-infrared high contrast images of the transitional disk HD 100546 taken with the Magellan Adaptive Optics system (MagAO) and the Gemini Planet Imager (GPI). GPI data include both polarized intensity and total intensity imagery, and MagAO data are taken in Simultaneous Differential Imaging mode at H{\alpha}. The new GPI H -band total intensity data represent a significant enhancement in sensitivity and field rotation compared to previous data sets and enable a detailed exploration of substructure in the disk. The data are processed with a variety of differential imaging techniques (polarized, angular, reference, and simultaneous differential imaging) in an attempt to identify the disk structures that are most consistent across wavelengths, processing techniques, and algorithmic parameters. The inner disk cavity at 15 au is clearly resolved in multiple datasets, as are a variety of spiral features. While the cavity and spiral structures are identified at levels significantly distinct from the neighboring regions of the disk under several algorithms and with a range of algorithmic parameters, emission at the location of HD 100546 c varies from point-like under aggressive algorithmic parameters to a smooth continuous structure with conservative parameters, and is consistent with disk emission. Features identified in the HD100546 disk bear qualitative similarity to computational models of a moderately inclined two-armed spiral disk, where projection effects and wrapping of the spiral arms around the star result in a number of truncated spiral features in forward-modeled images., Comment: accepted to AJ

Published
2017
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22. Integral Field Spectroscopy of the Low-Mass Companion HD984B with the Gemini Planet Imager

Author

Johnson-Groh, Mara, Marois, Christian, De Rosa, Robert J., Nielsen, Eric L., Rameau, Julien, Blunt, Sarah, Vargas, Jeffrey, Ammons, S. Mark, Bailey, Vanessa P., Barman, Travis S., Bulger, Joanna, Chilcote, Jeffrey K., Cotten, Tara, Doyon, Rene, Duchene, Gaspard, Fitzgerald, Michael P., Follette, Kate B., Goodsell, Stephen, Graham, James R., Greenbaum, Alexandra Z., Hibon, Pascale, Hung, Li-Wei, Ingraham, Patrick, Kalas, Paul, Konopacky, Quinn M., Larkin, James E., Macintosh, Bruce, Maire, Jerome, Marchis, Franck, Marley, Mark S., Metchev, Stanimir, Millar-Blanchaer, Maxwell A., Oppenheimer, Rebecca, Palmer, David W., Patience, Jenny, Perrin, Marshall, Poyneer, Lisa A., Pueyo, Laurent, Rajan, Abhijith, Rantakyro, Fredrik T., Savransky, Dmitry, Schneider, Adam C., Sivaramakrishnan, Anand, Song, Inseok, Soummer, Remi, Thomas, Sandrine, Vega, David, Wallace, J. Kent, Wang, Jason J., Ward-Duong, Kimberly, Wiktorowicz, Sloane J., and Wolff, Schuyler G.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We present new observations of the low-mass companion to HD 984 taken with the Gemini Planet Imager as a part of the Gemini Planet Imager Exoplanet Survey campaign. Images of HD 984 B were obtained in the J (1.12--1.3 micron) and H (1.50--1.80 micron) bands. Combined with archival epochs from 2012 and 2014, we fit the first orbit to the companion to find an 18 AU (70 year) orbit with a 68% confidence interval between 14 and 28 AU, an eccentricity of 0.18 with a 68% confidence interval between 0.05 and 0.47, and an inclination of 119 degrees with a 68% confidence interval between 114 degrees and 125 degrees. To address considerable spectral covariance in both spectra, we present a method of splitting the spectra into low and high frequencies to analyze the spectral structure at different spatial frequencies with the proper spectral noise correlation. Using the split spectra, we compare to known spectral types using field brown dwarf and low-mass star spectra and find a best fit match of a field gravity M6.5+/-1.5 spectral type with a corresponding temperature of 2730+120 K. Photometry of the companion yields a luminosity of log(L_bol/L_sun) = -2.88+/-0.07 dex, using DUSTY models. Mass estimates, again from DUSTY models, find an age-dependent mass of 34+/-1 to 95+/-4 M_Jup. These results are consistent with previous measurements of the object., Comment: Accepted for publication in The Astronomical Journal

Published
2017
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23. Enhancing patient outcomes: Integrating electronic cardiology consultation in primary care for cancer patients.

Author

Cinza‐Sanjurjo, Sergio, Mazón‐Ramos, Pilar, Rey‐Aldana, Daniel, Garcia‐Vega, David, Portela‐Romero, Manuel, Rodríguez‐Mañero, Moisés, Sestayo‐Fernández, Manuela, Lage‐Fernández, Ricardo, López‐López, Rafael, and González‐Juanatey, José R.

Subjects
CANCER patients, CARDIOLOGY, ELECTRONIC health records, CANCER prognosis, CANCER patient care, OUTPATIENT medical care
Abstract

Background: The prevalence of cancer patients with concomitant cardiovascular (CV) disease is on the rise due to improved cancer prognoses. The aim of this study is to evaluate the long‐term outcomes of cancer patients referred to a cardiology department (CD) via primary care using e‐consultation. Methods: We analysed data from cancer patients with prior referrals to a CD between 2010 and 2021 (n = 6889) and compared two care models: traditional in‐person consultations and e‐consultations. In e‐consultation model, cardiologists reviewed electronic health records (e‐consultation) to determine whether the demand could be addressed remotely or necessitated an in‐person consultation. We used an interrupted time series regression model to assess outcomes during the two periods: (1) time to cardiology consultation, (2) rates of all‐cause and CV related hospital admissions and (3) rates of all‐cause and CV‐related mortality within the first year after the initial consultation or e‐consultation at the CD. Results: Introduction of e‐consultation for cancer patients referred to cardiology care led to a 51.8% reduction (95%CI: 51.7%–51.9%) in waiting times. Furthermore, we observed decreased 1‐year incidence rates, with incidence rate ratios (iRRs) [IC95%] of.75 [.73–.77] for CV‐related hospitalizations,.43 [.42–.44] for all‐cause hospitalizations, and.87 [.86–.88] for all‐cause mortality. Conclusions: Compared to traditional in‐person consultations, an outpatient care program incorporating e‐consultation for cancer patients significantly reduced waiting times for cardiology care and demonstrated safety, associated with lower rates of hospital admissions. [ABSTRACT FROM AUTHOR]

Published
2024
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24. The Global Orchid Market

Author

Yuan, Shih-Chang, Lekawatana, Setapong, Amore, Teresita D., Chen, Fure-Chyi, Chin, Shih-Wen, Vega, David Monge, Wang, Yin-Tung, Kole, Chittaranjan, Series Editor, Chen, Fure-Chyi, editor, and Chin, Shih-Wen, editor

Published
2021
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25. This Article Corrects: "Coronary Disease in Emergency Department Chest Pain Patients with Recent Negative Stress Testing"

Author

Walker, Jonathan, Galuska, Michael, and Vega, David

Abstract

Background: Cardiac stress tests for diagnosis of coronary artery disease (CAD) are incompletely sensitive and specific.Objective: We examined the frequency of significant CAD in patients presenting to the emergency department (ED) with chest pain who have had a recent negative or inconclusive (

Published
2018

27. Outcomes of COVID-19 in patients with primary systemic vasculitis or polymyalgia rheumatica from the COVID-19 Global Rheumatology Alliance physician registry: a retrospective cohort study

Author

Dahou, Brahim, Rath, Eva, Piette, Yves, Devinck, Mieke, Maeyaert, Bea, Machado Ribeiro, Francinne, Euzebio Ribeiro, Sandra Lucia, Pinheiro, Marcelo, Quintana, Rosana, Gómez, Gimena, Roberts, Karen, Baez, Roberto Miguel, Castro Coello, Vanessa, Haye Salinas, María J., Maldonado, Federico Nicolas, Reyes Torres, Alvaro Andres, Alle, Gelsomina, Tanten, Romina, Maldonado Ficco, Hernán, Nieto, Romina, Gobbi, Carla, Tissera, Yohana, Pisoni, Cecilia, Paula, Alba, Albiero, Juan Alejandro, Schmid, Maria Marcela, Cosatti, Micaela, Gamba, Maria Julieta, Leandro, Carlevaris, Cusa, María Alejandra, German, Noelia, Bellomio, Veronica, Takashima, Lorena, Pera, Mariana, Cogo, Karina, Gálvez Elkin, Maria Soledad, Medina, María Alejandra, Savio, Veronica, Rojas Tessel, Ivana Romina, Perez Alamino, Rodolfo, Werner, Marina Laura, Ornella, Sofía, Casalla, Luciana, de la Vega, Maria, Severina, María, García, Mercedes, Gonzalez Lucero, Luciana, Romeo, Cecilia, Moyano, Sebastián, Barbich, Tatiana, Bertoli, Ana, Baños, Andrea, Petruzzelli, Sandra, Matellan, Carla, Conti, Silvana, Lazaro, Ma. Alicia, Rodriguez Gil, Gustavo Fabián, Risueño, Fabian, Quaglia, Maria Isabel, Scafati, Julia, Cuchiaro, Natalia Lili, Rebak, Jonathan Eliseo, Pineda, Susana Isabel, Calvo, María Elena, Picco, Eugenia, Gallino Yanzi, Josefina, Maid, Pablo, Guaglianone, Debora, Morbiducci, Julieta Silvana, Porta, Sabrina, Herscovich, Natalia, Velasco Zamora, José Luis, Kisluk, Boris, Castaños Menescardi, Maria Sol, Gallo, Rosana, Martire, María Victoria, Maldini, Carla, Goizueta, Cecilia, de la Vega Fernandez, Sabrina Solange, Aeschlimann, Carolina, Subils, Gisela, Ibáñez, Sebastián, Chassin-Trubert, Anne-Marie, Dong, Lingli, Cajas, Lui, Barešic, Marko, Anic, Branimir, Culo, Melanie-Ivana, Pavelic, Tea Ahel, Kovacevic Stranski, Kristina, Karanovic, Boris, Vencovsky, Jiri, Píchová, Marta, Filkova, Maria, Hamoud, Hesham, Vassilopoulos, Dimitrios, Guzman Melgar, Gabriela Maria, So, Ho, Király, Márta, Vojdanian, Mahdi, Balbir-Gurman, Alexandra, Abutiban, Fatemah, Zepa, Julija, Bulina, Inita, Bukauskiene, Loreta, Zaueta, Beatriz, Castillo Ortiz, Angel Alejandro, Zamora Tehozol, Erick, Vega, David, Cervántes Rosete, Diana, Martín Nares, Eduardo, Rodriguez-Reyna, Tatiana Sofia, Rull Gabayet, Marina, Alpízar-Rodríguez, Deshiré, Irazoque, Fedra, Jimenez, Xochitl, Geurts-van Bon, Lenny, Zijlstra, Theo, Hoekstra, Monique, Al-Adhoubi, Nasra, Salim, Babur, Giraldo, Enrique, Salinas, Ariel, Ugarte-Gil, Manuel, Nowakowski, Jaroslaw, Al-Emadi, Samar, Conway, Richard, Flood, Rachael, McCarthy, Geraldine, Felea, Ioana, Filipescu, Ileana, Rednic, Simona, Groseanu, Laura, Tamas, Maria Magdelena, Mlynarikova, Vanda, Skamlova, Martina, Zlnay, Martin, Miceková, Dagmar, Capova, Lubica, Macejova, Zelmira, Štenová, Emoke, Raffayova, Helena, Belakova, Gabriela, Strakova, Eva, Sencarová, Marieta, Žlnayová, Sona, Anna Sabová, Anna, Spisakova, Daniela, Oetterová, Mária, Lukacova, Olga, Bakosova, Martina, Hocevar, Alojzija, de la Torre-Rubio, Natalia, Alegre Sancho, Juan José, Corteguera Coro, Montserrat, Cobeta Garcia, Juan Carlos, Torres Martin, Maria Carmen, Campos, Jose, Gomez Puerta, Jose A, Yardimci, Gozd Kubra, Akar, Servet, Icacan, Ozan Cemal, Çelik, Selda, Vasylets, Viktoriia, Yeoh, Su-Ann, Vandevelde, Claire, Dunt, Sasha, Leeder, Jane, Macphie, Elizabeth, Salerno, Rosaria, Graver, Christine, Williams, Katie, O'Reilly, Sheila, Devine, Kirsty, Tyler, Jennifer, Warner, Elizabeth, Pilcher, James, Patel, Samir, Nikiphorou, Elena, Chadwick, Laura, Jones, Caroline Mulvaney, Harrison, Beverley, Thornton, Lucy, O'Kane, Diana, Fusi, Lucia, Low, Audrey, Horton, Sarah, Jatwani, Shraddha, Baig, Sara, Bajwa, Hammad, Berglund, Vernon, Dahle, Angela, Dorman, Walter, Hargrove, Jody, Hilton, Maren, Lebedoff, Nicholas, Leonard, Susan, Morgan, Jennifer, Pfeifer, Emily, Skemp, Archibald, Wilson, Jeffrey, Wolff, Anne, Cepeda, Eduardo, D'Silva, Kristin, Hsu, Tiffany, Patel, Naomi, Sparks, Jeffrey, Todd, Derrick, Wallace, Zachary, Hare, Denise, Calabrese, Cassandra, Adams, Christopher, Khosroshahi, Arezou, Kilian, Adam, White, Douglas, Winter, Melanie, Fields, Theodore, Siegel, Caroline, Daver, Nicole, Harvey, Melissa, Kramer, Neil, Lamore, Concetta, Hogarty, Suneya, Yeter, Karen, Wise, Leanna, Siddique, Faizah, Ban, Byung, Tanner, Tamar, Ruderman, Eric, Davis, William, Quinet, Robert, Scopelitis, Evangeline, Toribio Toribio, Karen, Webb-Detiege, Tameka, Zakem, Jerald, Abbass, Khurram, Kepecs, Gilbert, Miranda, Lilliam, Guma, Michael, Haikal, Ammar, Mody, Sushama, Mueller, Daric, Jayatilleke, Arundathi, Zell, JoAnn, Bays, Alison, Dao, Kathryn, Fatemeh, Ezzati, Parks, Deborah, Karp, David, Quiceno, Guillermo, Sattui, Sebastian E, Putman, Michael S, Seet, Andrea M, Gianfrancesco, Milena A, Beins, Kaley, Hill, Catherine, Liew, David, Mackie, Sarah L, Mehta, Puja, Neill, Lorna, Gomez, Gimena, Salinas, Maria Isabel Haye, Mariz, Henrique Ataide, de Sousa Studart, Samia Araujo, Araujo, Nafice Costa, Knight, Ann, Rozza, Davide, Quartuccio, Luca, Samson, Maxime, Bally, Stéphane, Maria, Alexandre TJ, Chazerain, Pascal, Hasseli, Rebecca, Müller-Ladner, Ulf, Hoyer, Bimba F, Voll, Reinhard, Torres, Rita Pinheiro, Luis, Mariana, Ribeirio, Sandra Lucia Euzebio, Sparks, Jeffrey A, Hsu, Tiffany Y-T, D’Silva, Kristin M, Patel, Naomi J, Gilbert, Emily, Almada, Maria Valenzuela, Duarte-García, Alí, Jacobsohn, Lindsay, Izadi, Zara, Strangfeld, Anja, Mateus, Elsa F, Hyrich, Kimme L, Gossec, Laure, Carmona, Loreto, Lawson-Tovey, Saskia, Kearsley-Fleet, Lianne, Schaefer, Martin, Sirotich, Emily, Hausmann, Jonathan S, Sufka, Paul, Bhana, Suleman, Liew, Jean W, Grainger, Rebecca, Machado, Pedro M, Wallace, Zachary S, Yazdany, Jinoos, and Robinson, Philip C

Published
2021
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28. Optical fluids: modeling the near field and far field optical effects of atmosphere and turbulent flow of an airborne laser communication system or imaging system.

Author

Lacava, Steven, primary, Mercado, Felipe, additional, Vega, David, additional, Mendes Lopes, Joao, additional, Carbajal, Esteban, additional, Kamel, Mohammed, additional, Viti, Valerio, additional, Miller, Craig, additional, Schwarz, Walter, additional, Herringer, Nick, additional, and Elliott, Erin, additional

Published
2024
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30. Imaging an 80 AU Radius Dust Ring Around the F5V Star HD 157587

Author

Millar-Blanchaer, Maxwell A., Wang, Jason, Kalas, Paul, Graham, James R., Duchene, Gaspard, Nielsen, Eric L., Perrin, Marshall, Moon, Dae-Sik, Padgett, Deborah, Metchev, Stanimir, Ammons, S. Mark, Bailey, Vanessa P., Barman, Travis, Bruzzone, Sebastian, Bulger, Joanna, Chen, Christine H., Chilcote, Jeffrey, Cotten, Tara, De Rosa, Robert J., Doyon, Rene, Draper, Zachary H., Esposito, Thomas M., Fitzgerald, Michael P., Follette, Katherine B., Gerard, Benjamin L., Greenbaum, Alexandra Z., Hibon, Pascale, Hinkley, Sasha, Hung, Li-Wei, Ingraham, Patrick, Johnson-Groh, Mara, Konopacky, Quinn, Larkin, James E., Macintosh, Bruce, Maire, Jerome, Marchis, Franck, Marley, Mark S., Marois, Christian, Matthews, Brenda C., Oppenheimer, Rebecca, Palmer, David, Patience, Jennifer, Poyneer, Lisa, Pueyo, Laurent, Rajan, Abhijith, Rameau, Julien, Rantakyro, Fredrik T., Savransky, Dmitry, Schneider, Adam C., Sivaramakrishnan, Anand, Song, Inseok, Soummer, Remi, Thomas, Sandrine, Vega, David, Wallace, J. Kent, Ward-Duong, Kimberly, Wiktorowicz, Sloane, and Wolff, Schuyler

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We present $H$-band near-infrared polarimetric imaging observations of the F5V star HD~157587 obtained with the Gemini Planet Imager (GPI) that reveal the debris disk as a bright ring structure at a separation of $\sim$80$-$100~AU. The new GPI data complement recent HST/STIS observations that show the disk extending out to over 500~AU. The GPI image displays a strong asymmetry along the projected minor axis as well as a fainter asymmetry along the projected major axis. We associate the minor and major axis asymmetries with polarized forward scattering and a possible stellocentric offset, respectively. To constrain the disk geometry we fit two separate disk models to the polarized image, each using a different scattering phase function. Both models favor a disk inclination of $\sim 70\degr$ and a $1.5\pm0.6$ AU stellar offset in the plane of the sky along the projected major axis of the disk. We find that the stellar offset in the disk plane, perpendicular to the projected major axis is degenerate with the form of the scattering phase function and remains poorly constrained. The disk is not recovered in total intensity due in part to strong adaptive optics residuals, but we recover three point sources. Considering the system's proximity to the galactic plane and the point sources' positions relative to the disk, we consider it likely that they are background objects and unrelated to the disk's offset from the star., Comment: Updated with proper references

Published
2016
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31. The Orbit and Transit Prospects for $\beta$ Pictoris b constrained with One Milliarcsecond Astrometry

Author

Wang, Jason J., Graham, James R., Pueyo, Laurent, Kalas, Paul, Millar-Blanchaer, Maxwell A., Ruffio, Jean-Baptiste, De Rosa, Robert J., Ammons, S. Mark, Arriaga, Pauline, Bailey, Vanessa P., Barman, Travis S., Bulger, Joanna, Burrows, Adam S., Cardwell, Andrew, Chen, Christine H., Chilcote, Jeffrey K., Cotten, Tara, Fitzgerald, Michael P., Follette, Katherine B., Doyon, René, Duchêne, Gaspard, Greenbaum, Alexandra Z., Hibon, Pascale, Hung, Li-Wei, Ingraham, Patrick, Konopacky, Quinn M., Larkin, James E., Macintosh, Bruce, Maire, Jérôme, Marchis, Franck, Marley, Mark S., Marois, Christian, Metchev, Stanimir, Nielsen, Eric L., Oppenheimer, Rebecca, Palmer, David W., Patel, Rahul, Patience, Jenny, Perrin, Marshall D., Poyneer, Lisa A., Rajan, Abhijith, Rameau, Julien, Rantakyrö, Fredrik T., Savransky, Dmitry, Sivaramakrishnan, Anand, Song, Inseok, Soummer, Remi, Thomas, Sandrine, Vasisht, Gautam, Vega, David, Wallace, J. Kent, Ward-Duong, Kimberly, Wiktorowicz, Sloane J., and Wolff, Schuyler G.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

A principal scientific goal of the Gemini Planet Imager (GPI) is obtaining milliarcsecond astrometry to constrain exoplanet orbits. However, astrometry of directly imaged exoplanets is subject to biases, systematic errors, and speckle noise. Here we describe an analytical procedure to forward model the signal of an exoplanet that accounts for both the observing strategy (angular and spectral differential imaging) and the data reduction method (Karhunen-Lo\`eve Image Projection algorithm). We use this forward model to measure the position of an exoplanet in a Bayesian framework employing Gaussian processes and Markov chain Monte Carlo (MCMC) to account for correlated noise. In the case of GPI data on $\beta$ Pic b, this technique, which we call Bayesian KLIP-FM Astrometry (BKA), outperforms previous techniques and yields 1$\sigma$-errors at or below the one milliarcsecond level. We validate BKA by fitting a Keplerian orbit to twelve GPI observations along with previous astrometry from other instruments. The statistical properties of the residuals confirm that BKA is accurate and correctly estimates astrometric errors. Our constraints on the orbit of $\beta$ Pic b firmly rule out the possibility of a transit of the planet at 10-$\sigma$ significance. However, we confirm that the Hill sphere of $\beta$ Pic b will transit, giving us a rare chance to probe the circumplanetary environment of a young, evolving exoplanet. We provide an ephemeris for photometric monitoring of the Hill sphere transit event, which will begin at the start of April in 2017 and finish at the end of January in 2018., Comment: 18 pages, 7 figures. Accepted to AJ. v2 corrects an error in plotting the full size of the Hill sphere in Figure 6

Published
2016
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32. Bringing 'The Moth' to Light: A Planet-Sculpting Scenario for the HD 61005 Debris Disk

Author

Esposito, Thomas M., Fitzgerald, Michael P., Graham, James R., Kalas, Paul, Lee, Eve J., Chiang, Eugene, Duchene, Gaspard, Wang, Jason, Millar-Blanchaer, Maxwell A., Nielsen, Eric, Ammons, S. Mark, Bruzzone, Sebastian, De Rosa, Robert J., Draper, Zachary H., Macintosh, Bruce, Marchis, Franck, Metchev, Stanimir A., Perrin, Marshall, Pueyo, Laurent, Rajan, Abhijith, Rantakyro, Fredrik T., Vega, David, and Wolff, Schuyler

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

The HD 61005 debris disk ("The Moth") stands out from the growing collection of spatially resolved circumstellar disks by virtue of its unusual swept-back morphology, brightness asymmetries, and dust ring offset. Despite several suggestions for the physical mechanisms creating these features, no definitive answer has been found. In this work, we demonstrate the plausibility of a scenario in which the disk material is shaped dynamically by an eccentric, inclined planet. We present new Keck NIRC2 scattered-light angular differential imaging of the disk at 1.2-2.3 microns that further constrains its outer morphology (projected separations of 27-135 AU). We also present complementary Gemini Planet Imager 1.6 micron total intensity and polarized light detections that probe down to projected separations less than 10 AU. To test our planet-sculpting hypothesis, we employed secular perturbation theory to construct parent body and dust distributions that informed scattered-light models. We found that this method produced models with morphological and photometric features similar to those seen in the data, supporting the premise of a planet-perturbed disk. Briefly, our results indicate a disk parent body population with a semimajor axis of 40-52 AU and an interior planet with an eccentricity of at least 0.2. Many permutations of planet mass and semimajor axis are allowed, ranging from an Earth mass at 35 AU to a Jupiter mass at 5 AU., Comment: Accepted to AJ; added Figure 5 and minor text edits

Published
2016
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33. The Peculiar Debris Disk of HD 111520 as Resolved by the Gemini Planet Imager

Author

Draper, Zachary H., Duchêne, Gaspard, Millar-Blanchaer, Maxwell A., Matthews, Brenda C., Wang, Jason J., Kalas, Paul, Graham, James R., Padgett, Deborah, Ammons, S. Mark, Bulger, Joanna, Chen, Christine, Chilcote, Jeffrey K., Doyon, René, Fitzgerald, Michael P., Follette, Kate B., Gerard, Benjamin, Greenbaum, Alexandra Z., Hibon, Pascale, Hinkley, Sasha, Macintosh, Bruce, Ingraham, Patrick, Lafrenière, David, Marchis, Franck, Marois, Christian, Nielsen, Eric L., Oppenheimer, Rebecca, Patel, Rahul, Patience, Jenny, Perrin, Marshall, Pueyo, Laurent, Rajan, Abhijith, Rameau, Julian, Sivaramakrishnan, Anand, Vega, David, Ward-Duong, Kimberly, and Wolff, Schuyler G.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Using the Gemini Planet Imager (GPI), we have resolved the circumstellar debris disk around HD 111520 at a projected range of ~30-100 AU in both total and polarized $H$-band intensity. The disk is seen edge-on at a position angle of ~165$^{\circ}$ along the spine of emission. A slight inclination or asymmetric warping are covariant and alters the interpretation of the observed disk emission. We employ 3 point spread function (PSF) subtraction methods to reduce the stellar glare and instrumental artifacts to confirm that there is a roughly 2:1 brightness asymmetry between the NW and SE extension. This specific feature makes HD 111520 the most extreme examples of asymmetric debris disks observed in scattered light among similar highly inclined systems, such as HD 15115 and HD 106906. We further identify a tentative localized brightness enhancement and scale height enhancement associated with the disk at ~40 AU away from the star on the SE extension. We also find that the fractional polarization rises from 10 to 40% from 0.5" to 0.8" from the star. The combination of large brightness asymmetry and symmetric polarization fraction leads us to believe that an azimuthal dust density variation is causing the observed asymmetry., Comment: 9 pages, 8 Figures, 1 table, Accepted to ApJ

Published
2016
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36. Complex Spiral Structure in the HD 100546 Transitional Disk as Revealed by GPI and MagAO

Author

Follette, Katherine B, Rameau, Julien, Dong, Ruobing, Pueyo, Laurent, Close, Laird M, Duchêne, Gaspard, Fung, Jeffrey, Leonard, Clare, Macintosh, Bruce, Males, Jared R, Marois, Christian, Millar-Blanchaer, Maxwell A, Morzinski, Katie M, Mullen, Wyatt, Perrin, Marshall, Spiro, Elijah, Wang, Jason, Ammons, S Mark, Bailey, Vanessa P, Barman, Travis, Bulger, Joanna, Chilcote, Jeffrey, Cotten, Tara, De Rosa, Robert J, Doyon, Rene, Fitzgerald, Michael P, Goodsell, Stephen J, Graham, James R, Greenbaum, Alexandra Z, Hibon, Pascale, Hung, Li-Wei, Ingraham, Patrick, Kalas, Paul, Konopacky, Quinn, Larkin, James E, Maire, Jérôme, Marchis, Franck, Metchev, Stanimir, Nielsen, Eric L, Oppenheimer, Rebecca, Palmer, David, Patience, Jennifer, Poyneer, Lisa, Rajan, Abhijith, Rantakyrö, Fredrik T, Savransky, Dmitry, Schneider, Adam C, Sivaramakrishnan, Anand, Song, Inseok, Soummer, Remi, Thomas, Sandrine, Vega, David, Wallace, J Kent, Ward-Duong, Kimberly, Wiktorowicz, Sloane, and Wolff, Schuyler

Subjects
instrumentation: adaptive optics, planet-disk interaction, protoplanetary disk, stars: individual, astro-ph.EP, Astronomical and Space Sciences, Astronomy & Astrophysics
Abstract

We present optical and near-infrared high-contrast images of the transitional disk HD 100546 taken with the Magellan Adaptive Optics system (MagAO) and the Gemini Planet Imager (GPI). GPI data include both polarized intensity and total intensity imagery, and MagAO data are taken in Simultaneous Differential Imaging mode at Hα. The new GPI H-band total intensity data represent a significant enhancement in sensitivity and field rotation compared to previous data sets and enable a detailed exploration of substructure in the disk. The data are processed with a variety of differential imaging techniques (polarized, angular, reference, and simultaneous differential imaging) in an attempt to identify the disk structures that are most consistent across wavelengths, processing techniques, and algorithmic parameters. The inner disk cavity at 15 au is clearly resolved in multiple data sets, as are a variety of spiral features. While the cavity and spiral structures are identified at levels significantly distinct from the neighboring regions of the disk under several algorithms and with a range of algorithmic parameters, emission at the location of HD 100546 "c" varies from point-like under aggressive algorithmic parameters to a smooth continuous structure with conservative parameters, and is consistent with disk emission. Features identified in the HD 100546 disk bear qualitative similarity to computational models of a moderately inclined two-armed spiral disk, where projection effects and wrapping of the spiral arms around the star result in a number of truncated spiral features in forward-modeled images.

Published
2017

37. Integral Field Spectroscopy of the Low-mass Companion HD 984 B with the Gemini Planet Imager

Author

Johnson-Groh, Mara, Marois, Christian, De Rosa, Robert J, Nielsen, Eric L, Rameau, Julien, Blunt, Sarah, Vargas, Jeffrey, Ammons, S Mark, Bailey, Vanessa P, Barman, Travis S, Bulger, Joanna, Chilcote, Jeffrey K, Cotten, Tara, Doyon, Rene, Duchene, Gaspard, Fitzgerald, Michael P, Follette, Kate B, Goodsell, Stephen, Graham, James R, Greenbaum, Alexandra Z, Hibon, Pascale, Hung, Li-Wei, Ingraham, Patrick, Kalas, Paul, Konopacky, Quinn M, Larkin, James E, Macintosh, Bruce, Maire, Jerome, Marchis, Franck, Marley, Mark S, Metchev, Stanimir, Millar-Blanchaer, Maxwell A, Oppenheimer, Rebecca, Palmer, David W, Patience, Jenny, Perrin, Marshall, Poyneer, Lisa A, Pueyo, Laurent, Rajan, Abhijith, Rantakyroe, Fredrik T, Savransky, Dmitry, Schneider, Adam C, Sivaramakrishnan, Anand, Song, Inseok, Soummer, Remi, Thomas, Sandrine, Vega, David, Wallace, J Kent, Wang, Jason J, Ward-Duong, Kimberly, Wiktorowicz, Sloane J, and Wolff, Schuyler G

Subjects
planetary systems, stars: individual, Astronomy & Astrophysics, Astronomical and Space Sciences
Published
2017

38. IMAGING AN 80 au RADIUS DUST RING AROUND THE F5V STAR HD 157587

Author

Millar-Blanchaer, Maxwell A, Wang, Jason J, Kalas, Paul, Graham, James R, Duchêne, Gaspard, Nielsen, Eric L, Perrin, Marshall, Moon, Dae-Sik, Padgett, Deborah, Metchev, Stanimir, Ammons, S Mark, Bailey, Vanessa P, Barman, Travis, Bruzzone, Sebastian, Bulger, Joanna, Chen, Christine H, Chilcote, Jeffrey, Cotten, Tara, De Rosa, Robert J, Doyon, Rene, Draper, Zachary H, Esposito, Thomas M, Fitzgerald, Michael P, Follette, Katherine B, Gerard, Benjamin L, Greenbaum, Alexandra Z, Hibon, Pascale, Hinkley, Sasha, Hung, Li-Wei, Ingraham, Patrick, Johnson-Groh, Mara, Konopacky, Quinn, Larkin, James E, Macintosh, Bruce, Maire, Jérôme, Marchis, Franck, Marley, Mark S, Marois, Christian, Matthews, Brenda C, Oppenheimer, Rebecca, Palmer, David, Patience, Jennifer, Poyneer, Lisa, Pueyo, Laurent, Rajan, Abhijith, Rameau, Julien, Rantakyrö, Fredrik T, Savransky, Dmitry, Schneider, Adam C, Sivaramakrishnan, Anand, Song, Inseok, Soummer, Remi, Thomas, Sandrine, Vega, David, Wallace, J Kent, Ward-Duong, Kimberly, Wiktorowicz, Sloane, and Wolff, Schuyler

Subjects
planet-disk interactions, stars: individual, techniques: polarimetric, astro-ph.EP, Astronomical and Space Sciences, Astronomy & Astrophysics
Abstract

We present H-band near-infrared polarimetric imaging observations of the F5V star HD 157587 obtained with the Gemini Planet Imager (GPI) that reveal the debris disk as a bright ring structure at a separation of ∼80-100 au. The new GPI data complement recent Hubble Space Telescope/STIS observations that show the disk extending out to over 500 au. The GPI image displays a strong asymmetry along the projected minor axis as well as a fainter asymmetry along the projected major axis. We associate the minor and major axis asymmetries with polarized forward scattering and a possible stellocentric offset, respectively. To constrain the disk geometry, we fit two separate disk models to the polarized image, each using a different scattering phase function. Both models favor a disk inclination of ∼70° and a 1.5 ± 0.6 au stellar offset in the plane of the sky along the projected major axis of the disk. We find that the stellar offset in the disk plane, perpendicular to the projected major axis is degenerate with the form of the scattering phase function and remains poorly constrained. The disk is not recovered in total intensity due in part to strong adaptive optics residuals, but we recover three point sources. Considering the system's proximity to the galactic plane and the point sources' positions relative to the disk, we consider it likely that they are background objects and unrelated to the disk's offset from the star.

Published
2016

39. Enhancing patient outcomes: Integrating electronic cardiology consultation in primary care for cancer patients

Author

Universidade de Santiago de Compostela. Centro de Investigación en Medicina Molecular e Enfermidades Crónicas, Universidade de Santiago de Compostela. Departamento de Bioquímica e Bioloxía Molecular, Universidade de Santiago de Compostela. Departamento de Psiquiatría, Radioloxía, Saúde Pública, Enfermaría e Medicina, González‐Juanatey, José R., Cinza Sanjurjo, Sergio, Mazón Ramos, Pilar, Rey Aldana, Daniel, Garcia Vega, David, Portela Romero, Manuel, Rodríguez Mañero, Moisés, Sestayo Fernández, Manuela, Lage Fernández, Ricardo, López López, Rafael, González Juanatey, José Ramón, Universidade de Santiago de Compostela. Centro de Investigación en Medicina Molecular e Enfermidades Crónicas, Universidade de Santiago de Compostela. Departamento de Bioquímica e Bioloxía Molecular, Universidade de Santiago de Compostela. Departamento de Psiquiatría, Radioloxía, Saúde Pública, Enfermaría e Medicina, González‐Juanatey, José R., Cinza Sanjurjo, Sergio, Mazón Ramos, Pilar, Rey Aldana, Daniel, Garcia Vega, David, Portela Romero, Manuel, Rodríguez Mañero, Moisés, Sestayo Fernández, Manuela, Lage Fernández, Ricardo, López López, Rafael, and González Juanatey, José Ramón

Abstract

Background: The prevalence of cancer patients with concomitant cardiovascular (CV) disease is on the rise due to improved cancer prognoses. The aim of this study is to evaluate the long-term outcomes of cancer patients referred to a cardiology department (CD) via primary care using e-consultation. Methods: We analysed data from cancer patients with prior referrals to a CD between 2010 and 2021 (n = 6889) and compared two care models: traditional in-person consultations and e-consultations. In e-consultation model, cardiologists reviewed electronic health records (e-consultation) to determine whether the demand could be addressed remotely or necessitated an in-person consultation. We used an interrupted time series regression model to assess outcomes during the two periods: (1) time to cardiology consultation, (2) rates of all-cause and CV related hospital admissions and (3) rates of all-cause and CV-related mortality within the first year after the initial consultation or e-consultation at the CD. Results: Introduction of e-consultation for cancer patients referred to cardiology care led to a 51.8% reduction (95%CI: 51.7%–51.9%) in waiting times. Furthermore, we observed decreased 1-year incidence rates, with incidence rate ratios (iRRs) [IC95%] of .75 [.73–.77] for CV-related hospitalizations, .43 [.42–.44] for all-cause hospitalizations, and .87 [.86–.88] for all-cause mortality. Conclusions: Compared to traditional in-person consultations, an outpatient care program incorporating e-consultation for cancer patients significantly reduced waiting times for cardiology care and demonstrated safety, associated with lower rates of hospital admissions

Published
2024

40. $\beta$ Pictoris' inner disk in polarized light and new orbital parameters for $\beta$ Pictoris b

Author

Millar-Blanchaer, Maxwell A., Graham, James R., Pueyo, Laurent, Kalas, Paul, Dawson, Rebekah I., Wang, Jason, Perrin, Marshall, Moon, Dae-Sik, Macintosh, Bruce, Ammons, S. Mark, Barman, Travis, Cardwell, Andrew, Chen, Christine H., Chiang, Eugene, Chilcote, Jeffrey, Cotten, Tara, De Rosa, Robert J., Draper, Zachary H., Dunn, Jennifer, Duchêne, Gaspard, Esposito, Thomas M., Fitzgerald, Michael P., Follette, Katherine B., Goodsell, Stephen J., Greenbaum, Alexandra Z., Hartung, Markus, Hibon, Pascale, Hinkley, Sasha, Ingraham, Patrick, Jensen-Clem, Rebecca, Konopacky, Quinn, Larkin, James E., Long, Douglas, Maire, Jérôme, Marchis, Franck, Marley, Mark S., Marois, Christian, Morzinski, Katie M., Nielsen, Eric L., Palmer, David W., Oppenheimer, Rebecca, Poyneer, Lisa, Rajan, Abhijith, Rantakyrö, Fredrik T., Ruffio, Jean-Baptiste, Sadakuni, Naru, Saddlemyer, Leslie, Schneider, Adam C., Sivaramakrishnan, Anand, Soummer, Remi, Thomas, Sandrine, Vasisht, Gautam, Vega, David, Wallace, J. Kent, Ward-Duong, Kimberly, Wiktorowicz, Sloane J., and Wolff, Schuyler G.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

We present $H$-band observations of $\beta$ Pic with the Gemini Planet Imager's (GPI's) polarimetry mode that reveal the debris disk between ~0.3" (~6 AU) and ~1.7" (~33 AU), while simultaneously detecting $\beta$ Pic $b$. The polarized disk image was fit with a dust density model combined with a Henyey-Greenstein scattering phase function. The best fit model indicates a disk inclined to the line of sight ($\phi=85.27{\deg}^{+0.26}_{-0.19}$) with a position angle $\theta_{PA}=30.35{\deg}^{+0.29}_{-0.28}$ (slightly offset from the main outer disk, $\theta_{PA}\approx29{\deg}$), that extends from an inner disk radius of $23.6^{+0.9}_{-0.6}$ AU to well outside GPI's field of view. In addition, we present an updated orbit for $\beta$ Pic $b$ based on new astrometric measurements taken in GPI's spectroscopic mode spanning 14 months. The planet has a semi-major axis of $a=9.2^{+1.5}_{-0.4}$AU, with an eccentricity $e\leq 0.26$. The position angle of the ascending node is $\Omega=31.75{\deg}\pm0.15$, offset from both the outer main disk and the inner disk seen in the GPI image. The orbital fit constrains the stellar mass of $\beta$ Pic to $1.60\pm0.05 M_{\odot}$. Dynamical sculpting by $\beta$ Pic $b$ cannot easily account for the following three aspects of the inferred disk properties: 1) the modeled inner radius of the disk is farther out than expected if caused by $\beta$ Pic b; 2) the mutual inclination of the inner disk and $\beta$ Pic $b$ is $4{\deg}$, when it is expected to be closer to zero; and 3) the aspect ratio of the disk ($h_0 = 0.137^{+0.005}_{-0.006}$) is larger than expected from interactions with $\beta$ Pic $b$ or self-stirring by the disk's parent bodies.

Published
2015
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41. The Impact of Transmission Technologies on the Evolution of the Electrical Grid

Author

Hernández-Callejo, Luis, Arrinda, Amaia, de la Vega, David, Fernández, Igor, Angulo, Itziar, Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Kotenko, Igor, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Barbosa, Simone Diniz Junqueira, Founding Editor, Washio, Takashi, Founding Editor, Yuan, Junsong, Founding Editor, Nesmachnow, Sergio, editor, and Hernández Callejo, Luis, editor

Published
2019
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43. THE ORBIT AND TRANSIT PROSPECTS FOR β PICTORIS b CONSTRAINED WITH ONE MILLIARCSECOND ASTROMETRY

Author

Wang, Jason J, Graham, James R, Pueyo, Laurent, Kalas, Paul, Millar-Blanchaer, Maxwell A, Ruffio, Jean-Baptiste, De Rosa, Robert J, Ammons, S Mark, Arriaga, Pauline, Bailey, Vanessa P, Barman, Travis S, Bulger, Joanna, Burrows, Adam S, Cardwell, Andrew, Chen, Christine H, Chilcote, Jeffrey K, Cotten, Tara, Fitzgerald, Michael P, Follette, Katherine B, Doyon, René, Duchêne, Gaspard, Greenbaum, Alexandra Z, Hibon, Pascale, Hung, Li-Wei, Ingraham, Patrick, Konopacky, Quinn M, Larkin, James E, Macintosh, Bruce, Maire, Jérôme, Marchis, Franck, Marley, Mark S, Marois, Christian, Metchev, Stanimir, Nielsen, Eric L, Oppenheimer, Rebecca, Palmer, David W, Patel, Rahul, Patience, Jenny, Perrin, Marshall D, Poyneer, Lisa A, Rajan, Abhijith, Rameau, Julien, Rantakyrö, Fredrik T, Savransky, Dmitry, Sivaramakrishnan, Anand, Song, Inseok, Soummer, Remi, Thomas, Sandrine, Vasisht, Gautam, Vega, David, Wallace, J Kent, Ward-Duong, Kimberly, Wiktorowicz, Sloane J, and Wolff, Schuyler G

Subjects
astrometry, planets and satellites: individual, techniques: image processing, astro-ph.EP, Astronomical and Space Sciences, Astronomy & Astrophysics
Abstract

A principal scientific goal of the Gemini Planet Imager (GPI) is obtaining milliarcsecond astrometry to constrain exoplanet orbits. However, astrometry of directly imaged exoplanets is subject to biases, systematic errors, and speckle noise. Here, we describe an analytical procedure to forward model the signal of an exoplanet that accounts for both the observing strategy (angular and spectral differential imaging) and the data reduction method (Karhunen-Loève Image Projection algorithm). We use this forward model to measure the position of an exoplanet in a Bayesian framework employing Gaussian processes and Markov-chain Monte Carlo to account for correlated noise. In the case of GPI data on β Pic b, this technique, which we call Bayesian KLIP-FM Astrometry (BKA), outperforms previous techniques and yields 1σ errors at or below the one milliarcsecond level. We validate BKA by fitting a Keplerian orbit to 12 GPI observations along with previous astrometry from other instruments. The statistical properties of the residuals confirm that BKA is accurate and correctly estimates astrometric errors. Our constraints on the orbit of β Pic b firmly rule out the possibility of a transit of the planet at 10-σ significance. However, we confirm that the Hill sphere of β Pic b will transit, giving us a rare chance to probe the circumplanetary environment of a young, evolving exoplanet. We provide an ephemeris for photometric monitoring of the Hill sphere transit event, which will begin at the start of April in 2017 and finish at the end of January in 2018.

Published
2016

44. BRINGING “THE MOTH” TO LIGHT: A PLANET-SCULPTING SCENARIO FOR THE HD 61005 DEBRIS DISK

Author

Esposito, Thomas M, Fitzgerald, Michael P, Graham, James R, Kalas, Paul, Lee, Eve J, Chiang, Eugene, Duchêne, Gaspard, Wang, Jason, Millar-Blanchaer, Maxwell A, Nielsen, Eric, Ammons, S Mark, Bruzzone, Sebastian, De Rosa, Robert J, Draper, Zachary H, Macintosh, Bruce, Marchis, Franck, Metchev, Stanimir A, Perrin, Marshall, Pueyo, Laurent, Rajan, Abhijith, Rantakyrö, Fredrik T, Vega, David, and Wolff, Schuyler

Subjects
infrared: planetary systems, planet-disk interactions, stars: individual, techniques: high angular resolution, techniques: polarimetric, astro-ph.EP, Astronomical and Space Sciences, Astronomy & Astrophysics
Abstract

The HD 61005 debris disk ("The Moth") stands out from the growing collection of spatially resolved circumstellar disks by virtue of its unusual swept-back morphology, brightness asymmetries, and dust ring offset. Despite several suggestions for the physical mechanisms creating these features, no definitive answer has been found. In this work, we demonstrate the plausibility of a scenario in which the disk material is shaped dynamically by an eccentric, inclined planet. We present new Keck NIRC2 scattered-light angular differential imaging of the disk at 1.2-2.3 μm that further constrains its outer morphology (projected separations of 27-135 au). We also present complementary Gemini Planet Imager 1.6 μm total intensity and polarized light detections that probe down to projected separations less than 10 au. To test our planet-sculpting hypothesis, we employed secular perturbation theory to construct parent body and dust distributions that informed scattered-light models. We found that this method produced models with morphological and photometric features similar to those seen in the data, supporting the premise of a planet-perturbed disk. Briefly, our results indicate a disk parent body population with a semimajor axis of 40-52 au and an interior planet with an eccentricity of at least 0.2. Many permutations of planet mass and semimajor axis are allowed, ranging from an Earth mass at 35 au to a Jupiter mass at 5 au.

Published
2016

45. THE PECULIAR DEBRIS DISK OF HD 111520 AS RESOLVED BY THE GEMINI PLANET IMAGER

Author

Draper, Zachary H, Duchêne, Gaspard, Millar-Blanchaer, Maxwell A, Matthews, Brenda C, Wang, Jason J, Kalas, Paul, Graham, James R, Padgett, Deborah, Ammons, S Mark, Bulger, Joanna, Chen, Christine, Chilcote, Jeffrey K, Doyon, René, Fitzgerald, Michael P, Follette, Kate B, Gerard, Benjamin, Greenbaum, Alexandra Z, Hibon, Pascale, Hinkley, Sasha, Macintosh, Bruce, Ingraham, Patrick, Lafrenière, David, Marchis, Franck, Marois, Christian, Nielsen, Eric L, Oppenheimer, Rebecca, Patel, Rahul, Patience, Jenny, Perrin, Marshall, Pueyo, Laurent, Rajan, Abhijith, Rameau, Julien, Sivaramakrishnan, Anand, Vega, David, Ward-Duong, Kimberly, and Wolff, Schuyler G

Subjects
circumstellar matter, stars: individual, astro-ph.EP, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Physical Chemistry (incl. Structural), Astronomy & Astrophysics
Abstract

Using the Gemini Planet Imager, we have resolved the circumstellar debris disk around HD 111520 at a projected range of ∼30-100 AU in both total and polarized H-band intensity. The disk is seen edge-on at a position angle of 165° along the spine of emission. A slight inclination and asymmetric warp are covariant and alter the interpretation of the observed disk emission. We employ three point-spread function subtraction methods to reduce the stellar glare and instrumental artifacts to confirm that there is a roughly 2:1 brightness asymmetry between the NW and SE extension. This specific feature makes HD 111520 the most extreme example of asymmetric debris disks observed in scattered light among similar highly inclined systems, such as HD 15115 and HD 106906. We further identify a tentative localized brightness enhancement and scale height enhancement associated with the disk at ∼40 AU away from the star on the SE extension. We also find that the fractional polarization rises from 10% to 40% from 0.″5 to 0.″8 from the star. The combination of large brightness asymmetry and symmetric polarization fraction leads us to believe that an azimuthal dust density variation is causing the observed asymmetry.

Published
2016

47. β PICTORIS’ INNER DISK IN POLARIZED LIGHT AND NEW ORBITAL PARAMETERS FOR β PICTORIS b

Author

Millar-Blanchaer, Maxwell A, Graham, James R, Pueyo, Laurent, Kalas, Paul, Dawson, Rebekah I, Wang, Jason, Perrin, Marshall D, moon, Dae-Sik, Macintosh, Bruce, Ammons, S Mark, Barman, Travis, Cardwell, Andrew, Chen, Christine H, Chiang, Eugene, Chilcote, Jeffrey, Cotten, Tara, De Rosa, Robert J, Draper, Zachary H, Dunn, Jennifer, Duchêne, Gaspard, Esposito, Thomas M, Fitzgerald, Michael P, Follette, Katherine B, Goodsell, Stephen J, Greenbaum, Alexandra Z, Hartung, Markus, Hibon, Pascale, Hinkley, Sasha, Ingraham, Patrick, Jensen-Clem, Rebecca, Konopacky, Quinn, Larkin, James E, Long, Douglas, Maire, Jérôme, Marchis, Franck, Marley, Mark S, Marois, Christian, Morzinski, Katie M, Nielsen, Eric L, Palmer, David W, Oppenheimer, Rebecca, Poyneer, Lisa, Rajan, Abhijith, Rantakyrö, Fredrik T, Ruffio, Jean-Baptiste, Sadakuni, Naru, Saddlemyer, Leslie, Schneider, Adam C, Sivaramakrishnan, Anand, Soummer, Remi, Thomas, Sandrine, Vasisht, Gautam, Vega, David, Wallace, J Kent, Ward-Duong, Kimberly, Wiktorowicz, Sloane J, and Wolff, Schuyler G

Subjects
astrometry, planet-disk interactions, planets and satellites: individual, techniques: polarimetric, astro-ph.EP, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Physical Chemistry (incl. Structural), Astronomy & Astrophysics
Abstract

We present H-band observations of β Pic with the Gemini Planet Imager's (GPI's) polarimetry mode that reveal the debris disk between ∼0.″3 (6 AU) and ∼1.″7 (33 AU), while simultaneously detecting β Pic b. The polarized disk image was fit with a dust density model combined with a Henyey-Greenstein scattering phase function. The best-fit model indicates a disk inclined to the line of sight () with a position angle (PA) (slightly offset from the main outer disk, ), that extends from an inner disk radius of to well outside GPI's field of view. In addition, we present an updated orbit for β Pic b based on new astrometric measurements taken in GPI's spectroscopic mode spanning 14 months. The planet has a semimajor axis of , with an eccentricity The PA of the ascending node is offset from both the outer main disk and the inner disk seen in the GPI image. The orbital fit constrains the stellar mass of β Pic to Dynamical sculpting by β Pic b cannot easily account for the following three aspects of the inferred disk properties: (1) the modeled inner radius of the disk is farther out than expected if caused by β Pic b; (2) the mutual inclination of the inner disk and β Pic b is when it is expected to be closer to zero; and (3) the aspect ratio of the disk () is larger than expected from interactions with β Pic b or self-stirring by the disk's parent bodies.

Published
2015

48. The Global Orchid Market

Author

Yuan, Shih-Chang, primary, Lekawatana, Setapong, additional, Amore, Teresita D., additional, Chen, Fure-Chyi, additional, Chin, Shih-Wen, additional, Vega, David Monge, additional, and Wang, Yin-Tung, additional

Published
2021
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50. Design and virtual validation of CMOS image sensor camera

Author

Lépine, Thierry, Babington, James, Gross, Herbert, Gely, Sandra, Nazari, Mina, Gilleran, TJ, Noygues, Sebastien, Meyer, Charly, Duque Gomez, Federico, Robertson, Taylor, Cheng, Michael, Vega, David, Morales, Angel, Chen, Chih-Hao, Shin, Dong Sub, and Cailler, Maxime

Published
2024
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