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The Importance of Optical Wavelength Data on Atmospheric Retrievals of Exoplanet Transmission Spectra Astron. J. (IF 5.3) Pub Date : 2024-04-24 Charlotte Fairman, Hannah R. Wakeford and Ryan J. MacDonald
Exoplanet transmission spectra provide rich information about the chemical composition, clouds, and temperature structure of exoplanet atmospheres. Most exoplanet transmission spectra only span infrared wavelengths (≳1 μm), which can preclude crucial atmospheric information from shorter wavelengths. Here, we explore how retrieved atmospheric parameters from exoplanet transmission spectra change with
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A Perfect Tidal Storm: HD 104067 Planetary Architecture Creating an Incandescent World Astron. J. (IF 5.3) Pub Date : 2024-04-24 Stephen R. Kane, Tara Fetherolf, Zhexing Li, Alex S. Polanski, Andrew W. Howard, Howard Isaacson, Teo Močnik and Sadie G. Welter
The discovery of planetary systems beyond the solar system has revealed a diversity of architectures, most of which differ significantly from our system. The initial detection of an exoplanet is often followed by subsequent discoveries within the same system as observations continue, measurement precision is improved, or additional techniques are employed. The HD 104067 system is known to consist of
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On the Rigidly Precessing, Eccentric Gas Disk Orbiting the White Dwarf SDSS J1228+1040 Astron. J. (IF 5.3) Pub Date : 2024-04-23 Olcay Ates Goksu, Taylor Kutra and Yanqin Wu
Metal pollution onto white dwarfs is a widespread phenomenon that remains puzzling. Some of these white dwarfs also harbor gaseous debris disks. Emission lines from these disks open a unique window to the physical properties of the polluting material, lending insights into their origin. We model the emission line kinematics for the gas disk around SDSS J1228+1040, a system that has been monitored for
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Planet Hunters NGTS: New Planet Candidates from a Citizen Science Search of the Next Generation Transit Survey Public Data Astron. J. (IF 5.3) Pub Date : 2024-04-23 Sean M. O’Brien, Megan E. Schwamb, Samuel Gill, Christopher A. Watson, Matthew R. Burleigh, Alicia Kendall, Sarah L. Casewell, David R. Anderson, José I. Vines, James S. Jenkins, Douglas R. Alves, Laura Trouille, Solène Ulmer-Moll, Edward M. Bryant, Ioannis Apergis, Matthew Battley, Daniel Bayliss, Nora L. Eisner, Edward Gillen, Michael R. Goad, Maximilian N. Günther, Beth A. Henderson, Jeong-Eun Heo
We present the results from the first two years of the Planet Hunters Next Generation Transit Survey (NGTS) citizen science project, which searches for transiting planet candidates in data from the NGTS by enlisting the help of members of the general public. Over 8000 registered volunteers reviewed 138,198 light curves from the NGTS Public Data Releases 1 and 2. We utilize a user weighting scheme to
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High-precision Atmospheric Characterization of a Y Dwarf with JWST NIRSpec G395H Spectroscopy: Isotopologue, C/O Ratio, Metallicity, and the Abundances of Six Molecular Species Astron. J. (IF 5.3) Pub Date : 2024-04-23 Ben W. P. Lew, Thomas Roellig, Natasha E. Batalha, Michael Line, Thomas Greene, Sagnick Murkherjee, Richard Freedman, Michael Meyer, Charles Beichman, Catarina Alves de Oliveira, Matthew De Furio, Doug Johnstone, Alexandra Z. Greenbaum, Mark Marley, Jonathan J. Fortney, Erick T. Young, Jarron Leisenring, Martha Boyer, Klaus Hodapp, Karl Misselt, John Stansberry and Marcia Rieke
The launch of the James Webb Space Telescope (JWST) marks a pivotal moment for precise atmospheric characterization of Y dwarfs, the coldest brown dwarf spectral type. In this study, we leverage moderate spectral resolution observations (R ∼ 2700) with the G395H grating of the Near-Infrared Spectrograph (NIRSpec) on board JWST to characterize the nearby (9.9 pc) Y dwarf WISEPA J182831.08+265037.8.
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Wide-spectral-band Nuller Insensitive to Finite Stellar Angular Diameter with a One-dimensional Diffraction-limited Coronagraph Astron. J. (IF 5.3) Pub Date : 2024-04-23 Satoshi Itoh, Taro Matsuo and Motohide Tamura
Potentially habitable planets around nearby stars less massive than solar-type stars could join targets of the spectroscopy of the planetary reflected light with future space telescopes. However, the orbits of most of these planets occur near the diffraction limit for 6 m diameter telescopes. Thus, while securing contrast-mitigation ability under a broad spectral bandwidth and a finite stellar angular
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Dynamical Structures under Nonrestricted Hierarchical Planetary Systems with Different Mass Ratios Astron. J. (IF 5.3) Pub Date : 2024-04-23 Xiumin Huang and Hanlun Lei
Secular dynamics have been extensively studied in both the inner and outer restricted hierarchical three-body systems. In the inner restricted problem, the quadrupole-order resonance (i.e., the well-known Kozai resonance) causes large coupled oscillations of eccentricity and inclination when the maximum inclination is higher than 39.2°, and the octupole-order resonance leads to the behavior of orbital
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Identification of the Top TESS Objects of Interest for Atmospheric Characterization of Transiting Exoplanets with JWST Astron. J. (IF 5.3) Pub Date : 2024-04-22 Benjamin J. Hord, Eliza M.-R. Kempton, Thomas M. Evans-Soma, David W. Latham, David R. Ciardi, Diana Dragomir, Knicole D. Colón, Gabrielle Ross, Andrew Vanderburg, Zoe L. de Beurs, Karen A. Collins, Cristilyn N. Watkins, Jacob Bean, Nicolas B. Cowan, Tansu Daylan, Caroline V. Morley, Jegug Ih, David Baker, Khalid Barkaoui, Natalie M. Batalha, Aida Behmard, Alexander Belinski, Zouhair Benkhaldoun, Paul
JWST has ushered in an era of unprecedented ability to characterize exoplanetary atmospheres. While there are over 5000 confirmed planets, more than 4000 Transiting Exoplanet Survey Satellite (TESS) planet candidates are still unconfirmed and many of the best planets for atmospheric characterization may remain to be identified. We present a sample of TESS planets and planet candidates that we identify
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Sites of Planet Formation in Binary Systems. I. Evidence for Disk−Orbit Alignment in the Close Binary FO Tau Astron. J. (IF 5.3) Pub Date : 2024-04-22 Benjamin M. Tofflemire, Lisa Prato, Adam L. Kraus, Dominique Segura-Cox, G. H. Schaefer, Rachel Akeson, Sean Andrews, Eric L. N. Jensen, Christopher M. Johns-Krull, J. J. Zanazzi and M. Simon
Close binary systems present challenges to planet formation. As binary separations decrease, so do the occurrence rates of protoplanetary disks in young systems and planets in mature systems. For systems that do retain disks, their disk masses and sizes are altered by the presence of the binary companion. Through the study of protoplanetary disks in binary systems with known orbital parameters, we
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Differencing and Coadding JWST Images with Matched Point-spread Function Astron. J. (IF 5.3) Pub Date : 2024-04-22 Lei Hu and Lifan Wang
We present an algorithm to derive difference images for data taken with JWST with matched point-spread functions (PSFs). It is based on the saccadic fast Fourier transform method but with revisions to accommodate the rotations and spatial variations of the PSFs. It allows for spatially varying kernels in B-spline form with separately controlled photometric scaling and Tikhonov kernel regularization
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Implication of the Velocity Dispersion Scalings on High-mass Star Formation in Molecular Clouds Astron. J. (IF 5.3) Pub Date : 2024-04-21 An-Xu Luo, Hong-Li Liu, Sheng-Li Qin, Dong-ting Yang and Sirong Pan
This paper is aimed at exploring the implications of velocity-dispersion scalings on high-mass star formation in molecular clouds, including the scalings of Larson’s linewidth–size (σ– R) and ratio–mass surface density ( – Σ; here = σ/R0.5). We have systematically analyzed the σ parameter of well-selected 221 massive clumps, complemented with published samples of other hierarchical density structures
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Is the RSGC4 (Alicante 8) Cluster a Real Star Cluster? Peculiar Radial Velocities of Red Supergiant Stars Astron. J. (IF 5.3) Pub Date : 2024-04-21 Sang-Hyun Chun, GyuChul Myeong, Jae-Joon Lee and Heeyoung Oh
Young massive star clusters, like the six red supergiant clusters in the Scutum complex, provide valuable insights into star formation and galaxy structures. We investigated the high-resolution near-infrared spectra of 60 RSG candidates in these clusters using the Immersion Grating Infrared Spectrograph. Among the candidates in RSGC4, we found significant scattering in radial velocity (−64 to 115 km
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How Well is the International Celestial Reference System Maintained in Official IAU Implementations? Astron. J. (IF 5.3) Pub Date : 2024-04-21 Zinovy Malkin
The International Celestial Reference Frame (ICRF) based on the VLBI-derived positions of 608 extragalactic radio sources was adopted by the International Astronomical Union (IAU) in 1998 as the first realization of the International Celestial Reference System (ICRS). Later, in 2009 and 2020, two extended ICRF versions, ICRF2 and ICRF3, respectively, were released. The latter is adopted by the IAU
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Prototype Faraday Rotation Measure Catalogs from the Polarisation Sky Survey of the Universe’s Magnetism (POSSUM) Pilot Observations Astron. J. (IF 5.3) Pub Date : 2024-04-18 S. Vanderwoude, J. L. West, B. M. Gaensler, L. Rudnick, C. L. Van Eck, A. J. M. Thomson, H. Andernach, C. S. Anderson, E. Carretti, G. H. Heald, J. P. Leahy, N. M. McClure-Griffiths, S. P. O’Sullivan, M. Tahani, A. G. Willis
The Polarisation Sky Survey of the Universe’s Magnetism (POSSUM) will conduct a sensitive ∼1 GHz radio polarization survey covering 20,000 deg2 of the southern sky with the Australian Square Kilometre Array Pathfinder. In anticipation of the full survey, we analyze pilot observations of low-band (800–1087 MHz), mid-band (1316–1439 MHz), and combined-band observations for an extragalactic field and
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Asteroseismological Analysis of the Non-Blazhko RRab Star EPIC 248846335 in the LAMOST–Kepler/K2 Project Astron. J. (IF 5.3) Pub Date : 2024-04-18 Peng Zong, Jian-Ning Fu, Jie Su, Xueying Hu, Bo Zhang, Jiaxin Wang, Gao-Chao Liu, Gang Meng, Gianni Catanzaro, Antonio Frasca, Haotian Wang, Weikai Zong
We conduct an asteroseismological analysis on the non-Blazhko ab-type RR Lyrae star EPIC 248846335, employing the Radial Stellar Pulsations module of the Modules for Experiments in Stellar Astrophysics based on the set of stellar parameters. The atmospheric parameters T eff = 6933 ± 70 K, log g = 3.35 ± 0.50, and [Fe/H] = −1.18 ± 0.14 are estimated from low-resolution spectra of LAMOST DR9. The luminosity
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Verification of Hypervelocity Bulge Red Clump Stars Astron. J. (IF 5.3) Pub Date : 2024-04-18 Gabriela Wojtkowska, Radosław Poleski
We verify candidate hypervelocity red clump stars located in the Galactic bulge that were selected based on the VVV and the Gaia DR2 data by Luna et al. To do so, we analyze data from the OGLE-IV survey: difference images and astrometric time series. We have data for 30 stars out of 34 hypervelocity candidates. We confirmed the high proper motion of only one of these stars and find out that it is a
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Modeling JWST MIRI-MRS Observations of T Cha: Mid-IR Noble Gas Emission Tracing a Dense Disk Wind Astron. J. (IF 5.3) Pub Date : 2024-04-17 Andrew D. Sellek, Naman S. Bajaj, Ilaria Pascucci, Cathie J. Clarke, Richard Alexander, Chengyan Xie, Giulia Ballabio, Dingshan Deng, Uma Gorti, Andras Gaspar, Jane Morrison
[Ne ii] 12.81 μm emission is a well-used tracer of protoplanetary disk winds due to its blueshifted line profile. Mid-Infrared Instrument (MIRI)-Medium Resolution Spectrometer (MRS) recently observed T Cha, detecting this line along with lines of [Ne iii], [Ar ii], and [Ar iii], with the [Ne ii] and [Ne iii] lines found to be extended while the [Ar ii] was not. In this complementary work, we use these
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Candidate Main-belt Asteroids for Surface Heterogeneity Astron. J. (IF 5.3) Pub Date : 2024-04-17 Sunao Hasegawa, Michaël Marsset, Francesca E. DeMeo, Josef Hanuš, Richard P. Binzel, Schelte J. Bus, Brian Burt, David Polishook, Cristina A. Thomas, Jooyeon Geem, Masateru Ishiguro, Daisuke Kuroda, Pierre Vernazza
Large terrestrial bodies in our solar system like the Earth, Mars, Mercury, and the Moon exhibit geologically complex surfaces with compositional heterogeneity. From past studies using large telescopes and spacecraft, it was shown that asteroids with diameters larger than 100 km also show surface heterogeneity at hemispheric scales, while on smaller objects, such features remain to be detected. Here
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Hyper Illumination of Exoplanets: Analytical and Numerical Approaches Astron. J. (IF 5.3) Pub Date : 2024-04-17 Jennifer L. Carter, Risinie D. Perera, M. J. Way
This work describes the illumination of exoplanets whose orbits are close enough to their host star that the finite angular size of their host star causes hyper illumination, in which more than 50% of the planet receives light. Such exoplanets include the hot Jupiters KELT-9 b (64.5% illuminated) and Kepler-91 b (69.6% illuminated). We describe the geometry of three primary illumination zones: the
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The Emerging Stellar Complex in Mon R2: Membership and Optical Variability Classification Astron. J. (IF 5.3) Pub Date : 2024-04-16 Sally D. Jiang, Lynne A. Hillenbrand
Monoceros R2 (Mon R2) is one of the closest large active star-forming regions. This extremely young and partially embedded region provides an excellent laboratory for studying star formation and the early evolution of young stellar objects (YSOs). In this paper, we conduct an optical study of the greater Mon R2 region. Beginning with 1690 previously identified candidate YSOs, we used 496 sources with
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The Multilayer Nature of Molecular Gas toward the Cygnus Region Astron. J. (IF 5.3) Pub Date : 2024-04-16 Shiyu Zhang, Yang Su, Xuepeng Chen, Min Fang, Qing-Zeng Yan, Shaobo Zhang, Yan Sun, Xiaolong Wang, Haoran Feng, Yuehui Ma, Miaomiao Zhang, Zi Zhuang, Xin Zhou, Zhiwei Chen, Ji Yang
We study the physical properties and 3D distribution of molecular clouds (MCs) toward the Cygnus region using the MWISP CO survey and Gaia DR3 data. Based on Gaussian decomposition and clustering for 13CO lines, over 70% of the fluxes are recovered. With the identification result of 13CO structures, two models are designed to measure the distances of the molecular gas in velocity crowding regions.
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A Data-driven Approach for Mitigating Dark Current Noise and Bad Pixels in Complementary Metal Oxide Semiconductor Cameras for Space-based Telescopes Astron. J. (IF 5.3) Pub Date : 2024-04-16 Peng Jia, Chao Lv, Yushan Li, Yongyang Sun, Shu Niu, Zhuoxiao Wang
In recent years, there has been a gradual increase in the performance of complementary metal oxide semiconductor (CMOS) cameras. These cameras have gained popularity as a viable alternative to charge-coupled device cameras in a wide range of applications. One particular application is the CMOS camera installed in small space telescopes. However, the limited power and spatial resources available on
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Elemental Abundances in the Diffuse Interstellar Medium from Joint Far-ultraviolet and X-Ray Spectroscopy: Iron, Oxygen, Carbon, and Sulfur Astron. J. (IF 5.3) Pub Date : 2024-04-15 I. Psaradaki, L. Corrales, J. Werk, A. G. Jensen, E. Costantini, M. Mehdipour, R. Cilley, N. Schulz, J. Kaastra, J. A. García, L. Valencic, T. Kallman, F. Paerels
In this study, we investigate interstellar absorption lines along the line of sight toward the galactic low-mass X-ray binary Cygnus X-2. We combine absorption line data obtained from high-resolution X-ray spectra collected with the Chandra and XMM-Newton satellites, along with far-UV absorption lines observed by the Hubble Space Telescope’s (HST) Cosmic Origins Spectrograph (COS) instrument. Our primary
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Detection of an Atmospheric Outflow from the Young Hot Saturn TOI-1268b Astron. J. (IF 5.3) Pub Date : 2024-04-15 Jorge Pérez-González, Michael Greklek-McKeon, Shreyas Vissapragada, Morgan Saidel, Heather A. Knutson, Dion Linssen, Antonija Oklopčić
Photoevaporative mass-loss rates are expected to be highest when planets are young and the host star is more active, but to date there have been relatively few measurements of mass-loss rates for young gas giant exoplanets. In this study we measure the present-day atmospheric mass-loss rate of TOI-1268b, a young (110–380 Myr) and low density (0.71 −0.13+0.17 g cm−3) hot Saturn located near the upper
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JWST COMPASS: NIRSpec/G395H Transmission Observations of the Super-Earth TOI-836b Astron. J. (IF 5.3) Pub Date : 2024-04-15 Lili Alderson, Natasha E. Batalha, Hannah R. Wakeford, Nicole L. Wallack, Artyom Aguichine, Johanna Teske, Jea Adams Redai, Munazza K. Alam, Natalie M. Batalha, Peter Gao, James Kirk, Mercedes López-Morales, Sarah E. Moran, Nicholas Scarsdale, Nicholas F. Wogan, Angie Wolfgang
We present two transit observations of the ∼870 K, 1.7 R ⊕ super-Earth TOI-836b with JWST NIRSpec/G395H, resulting in a 2.8–5.2 μm transmission spectrum. Using two different reduction pipelines, we obtain a median transit depth precision of 34 ppm for Visit 1 and 36 ppm for Visit 2, leading to a combined precision of 25 ppm in spectroscopic channels 30 pixels wide (∼0.02 μm). We find that the transmission
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Photometric and Spectroscopic Analysis of V583 Lyrae, an Algol with a g-mode Pulsating Primary and Accretion Disk Astron. J. (IF 5.3) Pub Date : 2024-04-15 H.-T Zhang, S.-B Qian, W.-P Liao, B. Soonthornthum, N. Sarotsakulchai
V583 Lyr is an extremely low-mass-ratio Algol-type binary with an orbital period of 11.2580 days. We determined an effective temperature of T eff1 = 9000 ± 350 K from newly observed spectra, which might be an underestimate due to binary mass transfer. The binary mass ratio q = 0.1 ± 0.004 and the orbital inclination i = 85.°5 are determined based on the assumption that the secondary fills its Roche
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Atmospheric Retrievals of the Young Giant Planet ROXs 42B b from Low- and High-resolution Spectroscopy Astron. J. (IF 5.3) Pub Date : 2024-04-15 Julie Inglis, Nicole L. Wallack, Jerry W. Xuan, Heather A. Knutson, Yayaati Chachan, Marta L. Bryan, Brendan P. Bowler, Aishwarya Iyer, Tiffany Kataria, Björn Benneke
Previous attempts have been made to characterize the atmospheres of directly imaged planets at low resolution (R ∼ 10–100 s), but the presence of clouds has often led to degeneracies in the retrieved atmospheric abundances with cloud opacity and temperature structure that bias retrieved compositions. In this study, we perform retrievals on the ultrayoung (≲5 Myr) directly imaged planet ROXs 42B b with
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Absolute Calibration. IV. Use of G-type Stars as Primary Calibrators Astron. J. (IF 5.3) Pub Date : 2024-04-12 G. H. Rieke, Everett Schlawin, Charles R. Proffitt, Christopher Willmer
We demonstrate an approach to determine spectral energy distribution (SED) templates that are accurate to the 1% level from the visible through the infrared for nearby (unextincted) solar-type stars. Our approach is based only on measurements of T eff, log(g), and M/H and the use of standard theoretical SED models. The success of this approach confirms that the existing absolute calibration is likely
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Velocity Dispersion of the Open Cluster NGC 2571 by Radial Velocities and Proper Motions Astron. J. (IF 5.3) Pub Date : 2024-04-12 Maxim V. Kulesh, Aleksandra E. Samirkhanova, Giovanni Carraro, Joao V. Sales-Silva, Roberto Capuzzo Dolcetta, Anton F. Seleznev
We use a kernel density estimator method to evaluate the stellar velocity dispersion in the open cluster NGC 2571. We derive the 3D velocity dispersion using both proper motions as extracted from Gaia Data Release 3 and single-epoch radial velocities as obtained with the instrument FLAMES at ESO's Very Large Telescope. The mean-square velocity along the line of sight is found to be larger than the
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Far-ultraviolet to Far-infrared Spectral Energy Distribution Modeling of the Star Formation History across M31 Astron. J. (IF 5.3) Pub Date : 2024-04-12 Denis A. Leahy, Jakob Hansen, Andrew M. Hopkins
Our neighboring galaxy M31 has been recently surveyed at the far- and near-ultraviolet (FUV and NUV) with the UVIT telescope on AstroSat, which provides unprecedented sensitivity to young stellar populations. Here the UVIT data are supplemented with optical data, near-infrared (IR) data (Spitzer), and mid- and far-IR data (Herschel). The observations are processed to obtain the spectral energy distributions
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The Occurrence of Small, Short-period Planets Younger than 200 Myr with TESS Astron. J. (IF 5.3) Pub Date : 2024-04-11 Sydney Vach, George Zhou, Chelsea X. Huang, James G. Rogers, L. G. Bouma, Stephanie T. Douglas, Michelle Kunimoto, Andrew W. Mann, Madyson G. Barber, Samuel N. Quinn, David W. Latham, Allyson Bieryla, Karen Collins
Within the first few hundreds of millions of years, many physical processes sculpt the eventual properties of young planets. NASA’s Transiting Exoplanet Survey Satellite (TESS) mission has surveyed young stellar associations across the entire sky for transiting planets, providing glimpses into the various stages of planetary evolution. Using our own detection pipeline, we search a magnitude-limited
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The APO-K2 Catalog. II. Accurate Stellar Ages for Red Giant Branch Stars across the Milky Way Astron. J. (IF 5.3) Pub Date : 2024-04-10 Jack T. Warfield, Joel C. Zinn, Jessica Schonhut-Stasik, James W. Johnson, Marc H. Pinsonneault, Jennifer A. Johnson, Dennis Stello, Rachael L. Beaton, Yvonne Elsworth, Rafael A. García, Savita Mathur, Benoît Mosser, Aldo Serenelli, Jamie Tayar
We present stellar age determinations for 4661 red giant branch stars in the APO-K2 catalog, derived using mass estimates from K2 asteroseismology from the K2 Galactic Archaeology Program and elemental abundances from the Apache Point Galactic Evolution Experiment survey. Our sample includes 17 of the 19 fields observed by K2, making it one of the most comprehensive catalogs of accurate stellar ages
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Relative Velocities between 13CO Structures within 12CO Molecular Clouds Astron. J. (IF 5.3) Pub Date : 2024-04-10 Lixia Yuan, Ji Yang, Xuepeng Chen, Yang Su, Shaobo Zhang, Xin Zhou, Zhiwei Chen, Qing-Zeng Yan, Min Fang, Fujun Du, Yan Sun, Hongchi Wang, Ye Xu
Velocity fields of molecular clouds (MCs) can provide crucial information on the merger and split between clouds, as well as their internal kinematics and maintenance, energy injection and redistribution, and even star formation within clouds. Using the CO spectral lines data from the Milky Way Imaging Scroll Painting survey, we measure the relative velocities along the line of sight (ΔV LOS) between
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Characterizing the Solar Cycle Variability Using Nonlinear Time Series Analysis at Different Amounts of Dynamo Supercriticality: Solar Dynamo is Not Highly Supercritical Astron. J. (IF 5.3) Pub Date : 2024-04-10 Aparup Ghosh, Pawan Kumar, Amrita Prasad, Bidya Binay Karak
The solar dynamo is essentially a cyclic process in which the toroidal component of the magnetic field is converted into the poloidal one and vice versa. This cyclic loop is disturbed by some nonlinear and stochastic processes mainly operating in the toroidal to poloidal part. Hence, the memory of the polar field decreases in every cycle. On the other hand, the dynamo efficiency and, thus, the supercriticality
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A Secular Solar System Resonance that Disrupts the Dominant Cycle in Earth’s Orbital Eccentricity (g 2 − g 5): Implications for Astrochronology Astron. J. (IF 5.3) Pub Date : 2024-04-09 Richard E. Zeebe, Margriet L. Lantink
The planets’ gravitational interaction causes rhythmic changes in Earth’s orbital parameters (also called Milanković cycles), which have powerful applications in geology and astrochronology. For instance, the primary astronomical eccentricity cycle due to the secular frequency term (g 2−g 5) (∼405 kyr in the recent past) utilized in deep-time analyses is dominated by the orbits of Venus and Jupiter
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A Subsolar Metallicity on the Ultra-short-period Planet HIP 65Ab Astron. J. (IF 5.3) Pub Date : 2024-04-09 Luc Bazinet, Stefan Pelletier, Björn Benneke, Ricardo Salinas, Gregory N. Mace
Studying and understanding the physical and chemical processes that govern hot Jupiters gives us insights on the formation of these giant planets. Having a constraint on the molecular composition of their atmosphere can help us pinpoint their evolution timeline. Namely, the metal enrichment and carbon-to-oxygen ratio can give us information about where in the protoplanetary disk a giant planet may
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DIAmante TESS AutoRegressive Planet Search (DTARPS). II. Hundreds of New TESS Candidate Exoplanets Astron. J. (IF 5.3) Pub Date : 2024-04-09 Elizabeth J. Melton, Eric D. Feigelson, Marco Montalto, Gabriel A. Caceres, Andrew W. Rosenswie, Cullen S. Abelson
The DIAmante TESS AutoRegressive Planet Search for the southern ecliptic hemisphere (DTARPS-S) project seeks to identify photometric transiting planets from 976,814 southern hemisphere stars observed in Year 1 of the TESS mission. This paper follows the methodology developed by Melton et al. (Paper I) using light curves extracted and preprocessed by the DIAmante project. Paper I emerged with a list
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DIAmante TESS AutoRegressive Planet Search (DTARPS). I. Analysis of 0.9 Million Light Curves Astron. J. (IF 5.3) Pub Date : 2024-04-09 Elizabeth J. Melton, Eric D. Feigelson, Marco Montalto, Gabriel A. Caceres, Andrew W. Rosenswie, Cullen S. Abelson
Nearly one million light curves from the TESS Year 1 southern hemisphere extracted from Full Field Images with the DIAmante pipeline are processed through the AutoRegressive Planet Search statistical procedure. ARIMA models remove lingering autocorrelated noise, the Transit Comb Filter identifies the strongest periodic signal in the light curve, and a Random Forest machine-learning classifier is trained
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Direct-imaging Discovery of a Substellar Companion Orbiting the Accelerating Variable Star HIP 39017 Astron. J. (IF 5.3) Pub Date : 2024-04-09 Taylor L. Tobin, Thayne Currie, Yiting Li, Jeffrey Chilcote, Timothy D. Brandt, Brianna Lacy, Masayuki Kuzuhara, Maria Vincent, Mona El Morsy, Vincent Deo, Jonathan P. Williams, Olivier Guyon, Julien Lozi, Sebastien Vievard, Nour Skaf, Kyohoon Ahn, Tyler Groff, N. Jeremy Kasdin, Taichi Uyama, Motohide Tamura, Aidan Gibbs, Briley L. Lewis, Rachel Bowens-Rubin, Maïssa Salama, Qier An, Minghan Chen
We present the direct-imaging discovery of a substellar companion (a massive planet or low-mass brown dwarf) to the young, γ Doradus (γ Dor)-type variable star HIP 39017 (HD 65526). The companion’s SCExAO/CHARIS JHK (1.1–2.4 μm) spectrum and Keck/NIRC2 L′ photometry indicate that it is an L/T transition object. A comparison of the JHK+L ′ spectrum to several atmospheric model grids finds a significantly
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The Long-term Photometric Behavior of 39 Semiregular Variable Stars Astron. J. (IF 5.3) Pub Date : 2024-04-08 Robert R. Cadmus
Photometric measurements of the light and color variations of 39 semiregular variable stars over a 30 yr time interval have been used to explore the systematics of these variations. These results show the complex nature of the frequency compositions of the light curves of these stars. The frequencies present in the light curves tend to be harmonic in nature, suggesting that both modes of pulsation
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The Cepheid Distance Scale: A Novel Method for Obtaining Mean Magnitudes from Single-epoch Observations Astron. J. (IF 5.3) Pub Date : 2024-04-08 Barry F. Madore, Wendy L. Freedman, Kayla Owens
We present a novel technique for mapping single-phase observations of Cepheids in any given band into their time-averaged values, using strong priors on the known interrelations of the multiwavelength widths of Cepheid period–luminosity (PL) relations, combined with the physical ordering of individual Cepheids within and across the instability strip, as a function of temperature (or radius). The method
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On an Application of the Hill Approach to the General Case of the Three-body Problem Astron. J. (IF 5.3) Pub Date : 2024-04-08 Stepan P. Sosnitskii
In this work, we use the energy and angular momentum integrals as a resource for applying Hill’s approach to the general three-body problem. As a result, we obtain theorems on the Lagrange stability and Hill stability in the general three-body problem. Also, specific features of the general and restricted three-body problems are discussed.
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Helium in the Extended Atmosphere of the Warm Superpuff TOI-1420b Astron. J. (IF 5.3) Pub Date : 2024-04-08 Shreyas Vissapragada, Michael Greklek-McKeon, Dion Linssen, Morgan MacLeod, Daniel P. Thorngren, Peter Gao, Heather A. Knutson, David W. Latham, Mercedes López-Morales, Antonija Oklopčić, Jorge Pérez González, Morgan Saidel, Abigail Tumborang, Stephanie Yoshida
Superpuffs are planets with exceptionally low densities (ρ ≲ 0.1 g cm−3) and core masses (M c ≲ 5M ⊕). Many lower-mass (M p ≲ 10M ⊕) superpuffs are expected to be unstable to catastrophic mass loss via photoevaporation and/or boil-off, whereas the larger gravitational potentials of higher-mass (M p ≳ 10M ⊕) superpuffs should make them more stable to these processes. We test this expectation by studying
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LHS 475 b: A Potential Venus Analog Orbiting a Nearby M Dwarf Astron. J. (IF 5.3) Pub Date : 2024-04-05 Kristo Ment, David Charbonneau, Jonathan Irwin, Jennifer G. Winters, Emily Pass, Avi Shporer, Karen A. Collins, Kevin I. Collins, Eric L. N. Jensen, Richard P. Schwarz, Keith Horne, Zahra Essack, Veselin B. Kostov, Michelle Kunimoto, Alan Levine, Sara Seager, Roland Vanderspek, Joshua N. Winn
Based on photometric observations by TESS, we present the discovery of a potential Venus analog transiting LHS 475, an M3 dwarf located 12.5 pc from the Sun. The mass of the star is 0.274 ± 0.015 M ☉. The planet, originally reported as TOI 910.01, has an orbital period of 2.0291010 ± 0.0000017 days and an estimated radius of 0.975 ± 0.058 R ⊕. We confirm the validity and source of the transit signal
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The Solar Neighborhood LI: A Variability Survey of Nearby M Dwarfs with Planets from Months to Decades with TESS and the CTIO/SMARTS 0.9 m Telescope Astron. J. (IF 5.3) Pub Date : 2024-04-05 Aman Kar, Todd J. Henry, Andrew A. Couperus, Eliot Halley Vrijmoet, Wei-Chun Jao
We present the optical photometric variability of 32 planet-hosting M dwarfs within 25 pc over timescales of months to decades. The primary goal of this project—A Trail to Life Around Stars (ATLAS)—is to follow the trail to life by revealing nearby M dwarfs with planets that are also “quiet,” which may make them more amiable to habitability. There are 69 reported exoplanets orbiting the 32 stars discussed
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Toward Atmospheric Retrievals of Panchromatic Light Curves: ExPLOR-ing Generalized Inversion Techniques for Transiting Exoplanets with JWST and Ariel Astron. J. (IF 5.3) Pub Date : 2024-04-05 Q. Changeat, Y. Ito, A. F. Al-Refaie, K. H. Yip, T. Lueftinger
Conventional atmospheric retrieval codes are designed to extract information, such as chemical abundances, thermal structures, and cloud properties, from fully “reduced” spectra obtained during transit or eclipse. Reduced spectra, however, are assembled by fitting a series of simplified light curves to time-series observations, wavelength by wavelength. Thus, spectra are postprocessed summary statistics
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Detection of Contact Binary Candidates Observed By TESS Using the Autoencoder Neural Network Astron. J. (IF 5.3) Pub Date : 2024-04-04 Xu Ding, ZhiMing Song, ChuanJun Wang, KaiFan Ji
A contact binary may be the progenitor of a red nova that eventually produces a merger event and have a cut-off period of around 0.2 days. Therefore, a large number of contact binaries is needed to search for the progenitor of red novae and to study the characteristics of short-period contact binaries. In this paper, we employ the Phoebe program to generate a large number of light curves based on the
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The TESS-Keck Survey. XVIII. A Sub-Neptune and Spurious Long-period Signal in the TOI-1751 System Astron. J. (IF 5.3) Pub Date : 2024-04-04 Anmol Desai, Emma V. Turtelboom, Caleb K. Harada, Courtney D. Dressing, David R. Rice, Joseph M. Akana Murphy, Casey L. Brinkman, Ashley Chontos, Ian J. M. Crossfield, Fei Dai, Michelle L. Hill, Tara Fetherolf, Steven Giacalone, Andrew W. Howard, Daniel Huber, Howard Isaacson, Stephen R. Kane, Jack Lubin, Mason G. MacDougall, Andrew W. Mayo, Teo Močnik, Alex S. Polanski, Malena Rice, Paul Robertson
We present and confirm TOI-1751 b, a transiting sub-Neptune orbiting a slightly evolved, solar-type, metal-poor star (T eff = 5996 ± 110 K, log(g)=4.2±0.1 , V = 9.3 mag, [Fe/H] = −0.40 ± 0.06 dex) every 37.47 days. We use TESS photometry to measure a planet radius of 2.77−0.07+0.15R⊕ . We also use both Keck/HIRES and APF/Levy radial velocities (RV) to derive a planet mass of 14.5−3.14+3.15M⊕ , and
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The Epoch of Giant Planet Migration Planet Search Program. II. A Young Hot Jupiter Candidate around the AB Dor Member HS Psc* * Based on observations obtained with the Hobby–Eberly Telescope (HET), which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Ludwig-Maximillians-Universitaet Muenchen, and Georg-August Universitaet Goettingen. The HET is named in Astron. J. (IF 5.3) Pub Date : 2024-04-04 Quang H. Tran, Brendan P. Bowler, William D. Cochran, Samuel Halverson, Suvrath Mahadevan, Joe P. Ninan, Paul Robertson, Guđmundur Stefánsson, Ryan C. Terrien
We report the discovery of a hot Jupiter candidate orbiting HS Psc, a K7 (≈0.7 M ⊙) member of the ≈130 Myr AB Doradus moving group. Using radial velocities over 4 yr from the Habitable-zone Planet Finder spectrograph at the Hobby–Eberly Telescope, we find a periodic signal of Pb=3.986−0.003+0.044 days. A joint Keplerian and Gaussian process stellar activity model fit to the radial velocities yields
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Binary Black Hole Mergers and Intermediate-mass Black Holes in Dense Star Clusters with Collisional Runaways Astron. J. (IF 5.3) Pub Date : 2024-04-04 Rujuta A. Purohit, Giacomo Fragione, Frederic A. Rasio, Grayson C. Petter, Ryan C. Hickox
Intermediate-mass black holes (IMBHs) are believed to be the missing link between the supermassive black holes (BHs) found at the centers of massive galaxies and BHs formed through stellar core collapse. One of the proposed mechanisms for their formation is a collisional runaway process in high-density young star clusters, where an unusually massive object forms through repeated stellar collisions
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Exploring NGC 2345: A Comprehensive Study of a Young Open Cluster through Photometric and Kinematic Analysis Astron. J. (IF 5.3) Pub Date : 2024-04-03 Kuldeep Belwal, D. Bisht, Mohit Singh Bisht, Geeta Rangwal, Ashish Raj, Arvind K. Dattatrey, R. K. S. Yadav, B. C. Bhatt
We conducted a photometric and kinematic analysis of the young open cluster NGC 2345 using CCD UBV data from 2 m Himalayan Chandra Telescope, Gaia Data Release 3, Two Micron All-Sky Survey, and the Photometric All-Sky Survey data sets. We found 1732 most probable cluster members with membership probability higher than 70%. The fundamental and structural parameters of the cluster are determined based
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Asteroid Collisions: Expected Visibility and Rate Astron. J. (IF 5.3) Pub Date : 2024-04-03 Eran O. Ofek, David Polishook, Doron Kushnir, Guy Nir, Sagi Ben-Ami, Yossi Shvartzvald, Nora L. Strotjohann, Enrico Segre, Arie Blumenzweig, Michael Engel, Dennis Bodewits, John W. Noonan
Asteroid collisions are one of the main processes responsible for the evolution of bodies in the main belt. Using observations of the Dimorphos impact by the DART spacecraft, we estimate how asteroid collisions in the main belt may look in the first hours after the impact. If the DART event is representative of asteroid collisions with a ∼1 m sized impactor, then the light curves of these collisions
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Methods for the Detection of Stellar Rotation Periods in Individual TESS Sectors and Results from the Prime Mission Astron. J. (IF 5.3) Pub Date : 2024-04-03 Isabel L. Colman, Ruth Angus, Trevor David, Jason Curtis, Soichiro Hattori, Yuxi (Lucy) Lu
For ongoing studies of the role of rotation in stellar evolution, we require large catalogs of rotation periods for testing and refining gyrochronology. While there is a wealth of data from the Kepler and K2 missions, the Transiting Exoplanet Survey Satellite (TESS) presents both an opportunity and a challenge: despite its all-sky coverage, rotation periods remain hard to detect. We analyzed individual
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Multiband Spectropolarimetry of Lunar Maria, Pyroclastics, Fresh Craters, and Swirl Materials Astron. J. (IF 5.3) Pub Date : 2024-04-02 Christian Wöhler, Mirza Arnaut, Megha Bhatt
Imaging polarimetry is a well-known method for examining the small-scale structure of the surface regolith of airless celestial bodies. In this study, we examine (for the first time) the wavelength-dependent polarization behavior of selected lunar areas, including maria, highlands, fresh craters, pyroclastic deposits, and the Reiner Gamma swirl, based on telescopic multiband UBVRI imaging polarimetry
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Spectroscopic Follow-up on Potential Magnetic Cataclysmic Variables Astron. J. (IF 5.3) Pub Date : 2024-04-02 Paula Szkody, Jan van Roestel, Paul A. Mason, Colin Littlefield, R. Michael Rich, Eric C. Bellm, Filipp D. Romanov, Brian F. Healy, Theophile Jegou du Laz, Russ R. Laher, Ben Rusholme
Spectroscopic observations of nine cataclysmic variables that have been postulated to contain magnetic white dwarfs were obtained to further characterize their classifications, orbital parameters, inclinations, and/or accretion properties. Zwicky Transient Facility (ZTF) and Transiting Exoplanet Survey Satellite (TESS) data were also used when available. This information enables these systems to be
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High-resolution Spectroscopic Analysis of Four Unevolved Barium Stars* * HD 15096, HD 37792, and HD 141804 were observed under the program ID 097.A-9024(A). HD 207585 was observed under the agreement between Observatório Nacional (Brazil) and the European Southern Observatory (ESO). Astron. J. (IF 5.3) Pub Date : 2024-03-28 M. P. Roriz, N. Holanda, L. V. da Conceição, S. Junqueira, N. A. Drake, A. Sonally, C. B. Pereira
A classical local thermodynamic equilibrium analysis, based on high-resolution spectroscopic data, is performed for a sample of three potential barium dwarf candidates and one star already recognized as such. We derived their atmospheric parameters, estimated their masses and luminosities, and determined chemical abundances for a set of 21 elements, including CNO. Some elemental abundances are derived
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JWST/NIRCam Imaging of Young Stellar Objects. I. Constraints on Planets Exterior to the Spiral Disk Around MWC 758 Astron. J. (IF 5.3) Pub Date : 2024-03-27 Kevin Wagner, Jarron Leisenring, Gabriele Cugno, Camryn Mullin, Ruobing Dong, Schuyler G. Wolff, Thomas Greene, Doug Johnstone, Michael R. Meyer, Charles Beichman, Martha Boyer, Scott Horner, Klaus Hodapp, Doug Kelly, Don McCarthy, Tom Roellig, George Rieke, Marcia Rieke, Michael Sitko, John Stansberry, Erick Young
MWC 758 is a young star hosting a spiral protoplanetary disk. The spirals are likely companion-driven, and two previously identified candidate companions have been identified—one at the end the Southern spiral arm at ∼0.″6, and one interior to the gap at ∼0.″1. With JWST/NIRCam, we provide new images of the disk and constraints on planets exterior to ∼1″. We detect the two-armed spiral disk, a known
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JWST/NIRCam Imaging of Young Stellar Objects. II. Deep Constraints on Giant Planets and a Planet Candidate Outside of the Spiral Disk Around SAO 206462 Astron. J. (IF 5.3) Pub Date : 2024-03-27 Gabriele Cugno, Jarron Leisenring, Kevin R. Wagner, Camryn Mullin, Roubing Dong, Thomas Greene, Doug Johnstone, Michael R. Meyer, Schuyler G. Wolff, Charles Beichman, Martha Boyer, Scott Horner, Klaus Hodapp, Doug Kelly, Don McCarthy, Thomas Roellig, George Rieke, Marcia Rieke, John Stansberry, Erick Young
We present JWST/NIRCam F187N, F200W, F405N, and F410M direct imaging data of the disk surrounding SAO 206462. Previous images show a very structured disk, with a pair of spiral arms thought to be launched by one or more external perturbers. The spiral features are visible in three of the four filters, with the nondetection in F410M due to the large detector saturation radius. We detect with a signal-to-noise
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A Formally Motivated Retrieval Framework Applied to the High-resolution Transmission Spectrum of HD 189733 b Astron. J. (IF 5.3) Pub Date : 2024-03-27 Doriann Blain, Alejandro Sánchez-López, Paul Mollière
Ground-based high-resolution spectra provide a powerful tool for characterizing exoplanet atmospheres. However, they are greatly hampered by the dominating telluric and stellar lines, which need to be removed prior to any analysis. Such removal techniques (“preparing pipelines”) deform the spectrum; hence, a key point is to account for this process in the forward models used in retrievals. We develop
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JWST/NIRCam Imaging of Young Stellar Objects. III. Detailed Imaging of the Nebular Environment around the HL Tau Disk Astron. J. (IF 5.3) Pub Date : 2024-03-27 Camryn Mullin, Ruobing Dong, Jarron Leisenring, Gabriele Cugno, Thomas Greene, Doug Johnstone, Michael R. Meyer, Kevin R. Wagner, Schuyler G. Wolff, Martha Boyer, Scott Horner, Klaus Hodapp, Don McCarthy, George Rieke, Marcia Rieke, Erick Young
As part of the James Webb Space Telescope (JWST) Guaranteed Time Observation program “Direct Imaging of YSOs” (program ID 1179), we use JWST NIRCam’s direct imaging mode in F187N, F200W, F405N, and F410M to perform high-contrast observations of the circumstellar structures surrounding the protostar HL Tau. The data reveal the known stellar envelope, outflow cavity, and streamers, but do not detect