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Full-Text Articles in Astrophysics and Astronomy

The Giant Accreting Protoplanet Survey (Gaplanets)—Results From A 6 Yr Campaign To Image Accreting Protoplanets, Katherine B. Follette, Laird M. Close, Jared R. Males, Kimberly Ward-Duong, William O. Balmer, Jéa Adams Redai, Julio Morales, Catherine Sarosi, Beck Dacus, Robert J. De Rosa, Fernando Garcia Toro, Clare Leonard, Bruce Macintosh, Katie M. Morzinski, Wyatt Mullen, Joseph Palmo, Raymond Nzaba Saitoti, Elijah Spiro, Helena Treiber, Kevin Wagner, Jason Wang, David Wang, Alex Watson, Alycia J. Weinberger Jun 2023

The Giant Accreting Protoplanet Survey (Gaplanets)—Results From A 6 Yr Campaign To Image Accreting Protoplanets, Katherine B. Follette, Laird M. Close, Jared R. Males, Kimberly Ward-Duong, William O. Balmer, Jéa Adams Redai, Julio Morales, Catherine Sarosi, Beck Dacus, Robert J. De Rosa, Fernando Garcia Toro, Clare Leonard, Bruce Macintosh, Katie M. Morzinski, Wyatt Mullen, Joseph Palmo, Raymond Nzaba Saitoti, Elijah Spiro, Helena Treiber, Kevin Wagner, Jason Wang, David Wang, Alex Watson, Alycia J. Weinberger

Astronomy: Faculty Publications

Accreting protoplanets are windows into planet formation processes, and high-contrast differential imaging is an effective way to identify them. We report results from the Giant Accreting Protoplanet Survey (GAPlanetS), which collected Hα differential imagery of 14 transitional disk host stars with the Magellan Adaptive Optics System. To address the twin challenges of morphological complexity and point-spread function instability, GAPlanetS required novel approaches for frame selection and optimization of the Karhounen-Loéve Image Processing algorithm pyKLIP. We detect one new candidate, CS Cha “c,” at a separation of 68 mas and a modest Δmag of 2.3. We recover the HD 142527 B …


Testing The Interaction Between A Substellar Companion And A Debris Disk In The Hr 2562 System, Stella Yimiao Zhang, Gaspard Duchêne, Robert J. De Rosa, Megan Ansdell, Quinn Konopacky, Thomas Esposito, Eugene Chiang, Malena Rice, Brenda Matthews, Paul Kalas, Bruce Macintosh, Franck Marchis, Stan Metchev, Jenny Patience, Julien Rameau, Kimberly Ward-Duong, Schuyler Wolff, Michael P. Fitzgerald, Vanessa P. Bailey, Travis S. Barman, Joanna Bulger, Christine H. Chen, Jeffrey K. Chilcotte, Tara Cotten, René Doyon, Katherine B. Follette, Benjamin L. Gerard, Stephen Goodsell, James R. Graham, Alexandra Z. Greenbaum, Pascale Hibon, Li Wei Hung May 2023

Testing The Interaction Between A Substellar Companion And A Debris Disk In The Hr 2562 System, Stella Yimiao Zhang, Gaspard Duchêne, Robert J. De Rosa, Megan Ansdell, Quinn Konopacky, Thomas Esposito, Eugene Chiang, Malena Rice, Brenda Matthews, Paul Kalas, Bruce Macintosh, Franck Marchis, Stan Metchev, Jenny Patience, Julien Rameau, Kimberly Ward-Duong, Schuyler Wolff, Michael P. Fitzgerald, Vanessa P. Bailey, Travis S. Barman, Joanna Bulger, Christine H. Chen, Jeffrey K. Chilcotte, Tara Cotten, René Doyon, Katherine B. Follette, Benjamin L. Gerard, Stephen Goodsell, James R. Graham, Alexandra Z. Greenbaum, Pascale Hibon, Li Wei Hung

Astronomy: Faculty Publications

The HR 2562 system is a rare case where a brown dwarf companion resides in a cleared inner hole of a debris disk, offering invaluable opportunities to study the dynamical interaction between a substellar companion and a dusty disk. We present the first ALMA observation of the system as well as the continued Gemini Planet Imager monitoring of the companion's orbit with six new epochs from 2016 to 2018. We update the orbital fit, and in combination with absolute astrometry from GAIA, place a 3σ upper limit of 18.5 M J on the companion's mass. To interpret the ALMA observations, …


The Jwst Early-Release Science Program For Direct Observations Of Exoplanetary Systems Ii: A 1 To 20 Μm Spectrum Of The Planetary-Mass Companion Vhs 1256-1257 B, Brittany E. Miles, Beth A. Biller, Polychronis Patapis, Kadin Worthen, Emily Rickman, Kielan K.W. Hoch, Andrew Skemer, Marshall D. Perrin, Niall Whiteford, Christine H. Chen, B. Sargent, Sagnick Mukherjee, Caroline V. Morley, Sarah E. Moran, Mickael Bonnefoy, Simon Petrus, Aarynn L. Carter, Elodie Choquet, Sasha Hinkley, Kimberly Ward-Duong, Jarron M. Leisenring, Maxwell A. Millar-Blanchaer, Laurent Pueyo, Shrishmoy Ray, Steph Sallum, Karl R. Stapelfeldt, Jordan M. Stone, Jason J. Wang, Olivier Absil, William O. Balmer, Anthony Boccaletti, Mariangela Bonavita Mar 2023

The Jwst Early-Release Science Program For Direct Observations Of Exoplanetary Systems Ii: A 1 To 20 Μm Spectrum Of The Planetary-Mass Companion Vhs 1256-1257 B, Brittany E. Miles, Beth A. Biller, Polychronis Patapis, Kadin Worthen, Emily Rickman, Kielan K.W. Hoch, Andrew Skemer, Marshall D. Perrin, Niall Whiteford, Christine H. Chen, B. Sargent, Sagnick Mukherjee, Caroline V. Morley, Sarah E. Moran, Mickael Bonnefoy, Simon Petrus, Aarynn L. Carter, Elodie Choquet, Sasha Hinkley, Kimberly Ward-Duong, Jarron M. Leisenring, Maxwell A. Millar-Blanchaer, Laurent Pueyo, Shrishmoy Ray, Steph Sallum, Karl R. Stapelfeldt, Jordan M. Stone, Jason J. Wang, Olivier Absil, William O. Balmer, Anthony Boccaletti, Mariangela Bonavita

Astronomy: Faculty Publications

We present the highest fidelity spectrum to date of a planetary-mass object. VHS 1256 b is a (∼8″, a = 150 au), young, planetary-mass companion that shares photometric colors and spectroscopic features with the directly imaged exoplanets HR 8799c, d, and e. As an L-to-T transition object, VHS 1256 b exists along the region of the color-magnitude diagram where substellar atmospheres transition from cloudy to clear. We observed VHS 1256 b with JWST's NIRSpec IFU and MIRI MRS modes for coverage from 1 to 20 μm at resolutions of ∼1000-3700. Water, methane, carbon monoxide, carbon dioxide, sodium, and potassium are …


Aggregate Effects Of Proliferating Low-Earth-Orbit Objects And Implications For Astronomical Data Lost In The Noise, John C. Barentine, Aparna Venkatesan, Jessica Heim, James Lowenthal, Miroslav Kocifaj, Salvador Bará Mar 2023

Aggregate Effects Of Proliferating Low-Earth-Orbit Objects And Implications For Astronomical Data Lost In The Noise, John C. Barentine, Aparna Venkatesan, Jessica Heim, James Lowenthal, Miroslav Kocifaj, Salvador Bará

Astronomy: Faculty Publications

The rising population of artificial satellites and associated debris in low-altitude orbits is increasing the overall brightness of the night sky, threatening ground-based astronomy as well as a diversity of stakeholders and ecosystems reliant on dark skies. We present calculations of the potentially large rise in global sky brightness from space objects in low Earth orbit, including qualitative and quantitative assessments of how professional astronomy may be affected. Debris proliferation is of special concern: we calculate that all log-decades in debris size contribute approximately the same amount of night sky radiance, so debris-generating events are expected to lead to a …


Correlating Changes In Spot Filling Factors With Stellar Rotation: The Case Of Lkca 4, Facundo Pérez Paolino, Jeffrey S. Bary, Michael S. Petersen, Kimberly Ward-Duong, Benjamin M. Tofflemire, Katherine B. Follette, Heidi Mach Mar 2023

Correlating Changes In Spot Filling Factors With Stellar Rotation: The Case Of Lkca 4, Facundo Pérez Paolino, Jeffrey S. Bary, Michael S. Petersen, Kimberly Ward-Duong, Benjamin M. Tofflemire, Katherine B. Follette, Heidi Mach

Astronomy: Faculty Publications

We present a multi-epoch spectroscopic study of LkCa 4, a heavily spotted non-accreting T Tauri star. Using SpeX at NASA’s Infrared Telescope Facility (IRTF), 12 spectra were collected over five consecutive nights, spanning ≈1.5 stellar rotations. Using the IRTF SpeX Spectral Library, we constructed empirical composite models of spotted stars by combining a warmer (photosphere) standard star spectrum with a cooler (spot) standard weighted by the spot filling factor, f spot. The best-fit models spanned two photospheric component temperatures, T phot = 4100 K (K7V) and 4400 K (K5V), and one spot component temperature, T spot = 3060 K (M5V) …


Direct Discovery Of The Inner Exoplanet In The Hd 206893 System: Evidence For Deuterium Burning In A Planetary-Mass Companion, S. Hinkley, S. Lacour, G. D. Marleau, A. M. Lagrange, J. J. Wang, J. Kammerer, A. Cumming, M. Nowak, L. Rodet, T. Stolker, W. O. Balmer, S. Ray, M. Bonnefoy, P. Mollière, C. Lazzoni, G. Kennedy, C. Mordasini, R. Abuter, S. Aigrain, A. Amorim, R. Asensio-Torres, C. Babusiaux, M. Benisty, J. P. Berger, H. Beust, S. Blunt, A. Boccaletti, Kimberly Ward-Huong, Et Al Mar 2023

Direct Discovery Of The Inner Exoplanet In The Hd 206893 System: Evidence For Deuterium Burning In A Planetary-Mass Companion, S. Hinkley, S. Lacour, G. D. Marleau, A. M. Lagrange, J. J. Wang, J. Kammerer, A. Cumming, M. Nowak, L. Rodet, T. Stolker, W. O. Balmer, S. Ray, M. Bonnefoy, P. Mollière, C. Lazzoni, G. Kennedy, C. Mordasini, R. Abuter, S. Aigrain, A. Amorim, R. Asensio-Torres, C. Babusiaux, M. Benisty, J. P. Berger, H. Beust, S. Blunt, A. Boccaletti, Kimberly Ward-Huong, Et Al

Astronomy: Faculty Publications

Aims. HD 206893 is a nearby debris disk star that hosts a previously identified brown dwarf companion with an orbital separation of ~ 10 au. Long-Term precise radial velocity (RV) monitoring, as well as anomalies in the system proper motion, has suggested the presence of an additional, inner companion in the system. Methods. Using information from ongoing precision RV measurements with the HARPS spectrograph, as well as Gaia host star astrometry, we have undertaken a multi-epoch search for the purported additional planet using the VLTI/GRAVITY instrument. Results. We report a high-significance detection over three epochs of the companion HD 206893c, …


The Giant Accreting Protoplanet Survey (Gaplanets): Optimization Techniques For Robust Detections Of Protoplanets, Jéa I. Adams Redai, Katherine B. Follette, Jason Wang, Clare Leonard, William Balmer, Laird M. Close, Beck Dacus, Jared R. Males, Katie M. Morzinski, Joseph Palmo, Laurent Pueyo, Elijah Spiro, Helena Treiber, Kimberly Ward-Duong, Alex Watson Feb 2023

The Giant Accreting Protoplanet Survey (Gaplanets): Optimization Techniques For Robust Detections Of Protoplanets, Jéa I. Adams Redai, Katherine B. Follette, Jason Wang, Clare Leonard, William Balmer, Laird M. Close, Beck Dacus, Jared R. Males, Katie M. Morzinski, Joseph Palmo, Laurent Pueyo, Elijah Spiro, Helena Treiber, Kimberly Ward-Duong, Alex Watson

Astronomy: Faculty Publications

High-contrast imaging has afforded astronomers the opportunity to study light directly emitted by adolescent (tens of megayears) and “proto” (<10 >Myr) planets still undergoing formation. Direct detection of these planets is enabled by empirical point-spread function (PSF) modeling and removal algorithms. The computational intensity of such algorithms, as well as their multiplicity of tunable input parameters, has led to the prevalence of ad hoc optimization approaches to high-contrast imaging results. In this work, we present a new, systematic approach to optimization vetted using data of the high-contrast stellar companion HD 142527 B from the Magellan Adaptive Optics Giant Accreting Protoplanet …


Spatially Resolved Imaging Of The Inner Fomalhaut Disk Using Jwst/Miri, András Gáspár, Schuyler Grace Wolff, George H. Rieke, Jarron M. Leisenring, Jane Morrison, Kate Y.L. Su, Kimberly Ward-Duong, Jonathan Aguilar, Marie Ygouf, Charles Beichman, Jorge Llop-Sayson, Geoffrey Bryden Jan 2023

Spatially Resolved Imaging Of The Inner Fomalhaut Disk Using Jwst/Miri, András Gáspár, Schuyler Grace Wolff, George H. Rieke, Jarron M. Leisenring, Jane Morrison, Kate Y.L. Su, Kimberly Ward-Duong, Jonathan Aguilar, Marie Ygouf, Charles Beichman, Jorge Llop-Sayson, Geoffrey Bryden

Astronomy: Faculty Publications

Planetary debris disks around other stars are analogous to the asteroid and Kuiper belts in the Solar System. Their structure reveals the configuration of small bodies and provides hints for the presence of planets. The nearby star Fomalhaut hosts one of the most prominent debris disks, resolved by the Hubble Space Telescope, Spitzer, Herschel and the Atacama Large Millimeter Array. Images of this system at mid-infrared wavelengths using JWST/MIRI not only show the narrow Kuiper belt-analogue outer ring, but also that (1) what was thought from indirect evidence to be an asteroid-analogue structure is instead broad, extending outward into the …