Article
Astronomy & Astrophysics
Jun Hashimoto, Takayuki Muto, Ruobing Dong, Yasuhiro Hasegawa, Nienke van der Marel, Motohide Tamura, Michihiro Takami, Munetake Momose
Summary: Observations of the protoplanetary disk around T Tauri star Sz 84 reveal the presence of two different-sized cavities, with large dust grains dominating the number of small dust grains in the region below 60 au. This suggests that weak turbulence and/or stickier dust grains may lead to efficient growth of dust grains in this area.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Tamara Molyarova, Eduard I. Vorobyov, Vitaly Akimkin, Aleksandr Skliarevskii, Dmitri Wiebe, Manuel Guedel
Summary: The snowlines of volatile species in protoplanetary disks are influenced by changes in gas composition and dust physical properties, leading to complex distribution patterns. As the disk evolves, the snowlines shift closer to the star, with volatile molecules tending to accumulate near these snowlines, forming thick icy mantles potentially important for dust dynamics.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
S. K. Betti, K. Follette, S. Jorquera, G. Duchene, J. Mazoyer, M. Bonnefoy, G. Chauvin, L. M. Perez, A. Boccaletti, C. Pinte, A. J. Weinberger, C. Grady, L. M. Close, D. Defrere, E. C. Downey, P. M. Hinz, F. Menard, G. Schneider, A. J. Skemer, A. Vaz
Summary: The study utilized the LMIRCam imagery from the Large Binocular Telescope to explore the disk around the suspected Herbig Ae/Be star AB Aurigae, revealing morphological differences between different bands that could be related to the presence of icy grains. The analysis suggests that the scattering surfaces at different wavelengths are not colocated, leading to varying optical depth effects and indicating potential differences in grain population at different depths of the disk surface.
ASTRONOMICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Kazuhiro D. Kanagawa, Jun Hashimoto, Takayuki Muto, Takashi Tsukagoshi, Sanemichi Z. Takahashi, Yasuhiro Hasegawa, Mihoko Konishi, Hideko Nomura, Hauyu Baobab Liu, Ruobing Dong, Akimasa Kataoka, Munetake Momose, Tomohiro Ono, Michael Sitko, Michihiro Takami, Kengo Tomida
Summary: The ALMA Band 6 observations of the disk around WW Cha reveal a smooth disk structure with a faint dust ring extending from about 40 au to 70 au, without any gap, and with two peaks at 40 au and 70 au. An analysis of the visibility data using a simple model and radiative transfer simulations suggest asymmetric structures in the disk, with temperatures around 30 K at the outer peak and 50 K at the inner peak, consistent with freezing temperatures of CO on water ice and H2S, respectively. The size distribution of dust grains was discussed based on spectral index maps obtained from the observations.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Nienke van der Marel, Til Birnstiel, Antonio Garufi, Enrico Ragusa, Valentin Christiaens, Daniel J. Price, Steph Sallum, Dhruv Muley, Logan Francis, Ruobing Dong
Summary: Research suggests that the asymmetry in protoplanetary disks is mainly associated with higher Stokes numbers or low gas surface density. The gas gap radius is approximately 2 times smaller than the dust ring radius, indicating that the companions in these disks have estimated masses ranging from 15-50 M_Jup or 3-15 M_Jup, and are in eccentric orbits.
ASTRONOMICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Hans Baehr, Zhaohuan Zhu
Summary: Observations indicate that protoplanetary disks have moderate accretion rates and weak dust settling. Simulations show that gravitationally unstable disks can maintain moderate high accretion rates while keeping a relatively thin dust disk due to the strong self-gravity stress and gas gravity effects on dust.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Hans Baehr, Zhaohuan Zhu
Summary: The study found that the opening angles of spirals in self-gravitating disks are universal, approximately 10 degrees, and not significantly affected by simulation size, cooling time, or particle size. Large dust particles exhibit spirals, attributed to the gravitational force from gas to dust components.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Yao Liu, Hendrik Linz, Min Fang, Thomas Henning, Sebastian Wolf, Mario Flock, Giovanni P. Rosotti, Hongchi Wang, Dafa Li
Summary: This study investigates the underestimation of dust mass in protoplanetary disks by analyzing the effects of disk structure and dust properties through radiative transfer models. The results show that the traditional analytic method can significantly underestimate the dust mass. Radiative transfer modeling provides a solution to this problem.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
R. Carini, K. Biazzo, G. De Marchi, N. Panagia, G. Beccari, E. Brocato
Summary: In this study, the accretion properties of low-mass pre-main sequence stars in the LH 91 association within the Large Magellanic Clouds are investigated using optical multiband photometry obtained with the Hubble Space Telescope. The age distribution suggests a period of active star formation ranging from a few million years up to approximately 60 million years, with a gap between 5 million years and 10 million years. The masses of the pre-main sequence candidates range from 0.2 solar masses to 1.0 solar mass, with an average of approximately 0.80 solar mass. The results also show variations in accretion luminosity and mass accretion rate with the age of the stars. Comparison with LH 95 reveals that LH 91 appears to be in a more evolved stage. Additionally, the pre-main sequence candidates are found to be uniformly distributed without any evidence of clumps around more massive stars.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Karina Mauco, Carlos Carrasco-Gonzalez, Matthias R. Schreiber, Anibal Sierra, Johan Olofsson, Amelia Bayo, Claudio Caceres, Hector Canovas, Aina Palau
Summary: Observations of the transition disk system Sz 91 with ALMA show accumulation of dust particles in the millimeter ring influenced by a gas pressure bump, in line with simulations of grain growth in disk substructures.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
Sota Arakawa, Sebastiaan Krijt
Summary: Laboratory experiments showed that CO2 ice particles have lower sticking efficiency compared to H2O ice particles due to differences in viscoelastic dissipation strength, even though their surface energies and elastic moduli are similar. The threshold velocity for sticking of CO2 ice particles is comparable to that for perfectly elastic spheres, while for H2O ice particles, it is an order of magnitude higher.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
N. T. Kurtovic, P. Pinilla, F. Long, M. Benisty, C. F. Manara, A. Natta, I Pascucci, L. Ricci, A. Scholz, L. Testi
Summary: The discovery of giant planets orbiting very low mass stars (VLMS) and observed substructures in disks around VLMS challenge existing planet formation models. Observations show the presence of cavities, rings, and gaps in disks around VLMS, providing insights into radial drift. Additionally, the comparison of gas and dust emission in these disks reveals valuable information about radial extent and structural formation.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
J. Varga, M. Hogerheijde, R. van Boekel, L. Klarmann, R. Petrov, L. B. F. M. Waters, S. Lagarde, E. Pantin, Ph Berio, G. Weigelt, S. Robbe-Dubois, B. Lopez, F. Millour, J-C Augereau, H. Meheut, A. Meilland, Th Henning, W. Jaffe, F. Bettonvil, P. Bristow, K-H Hofmann, A. Matter, G. Zins, S. Wolf, F. Allouche, F. Donnan, D. Schertl, C. Dominik, M. Heininger, M. Lehmitz, P. Cruzalebes, A. Glindemann, K. Meisenheimer, C. Paladini, M. Schoeller, J. Woillez, L. Venema, E. Kokoulina, G. Yoffe, P. Abraham, S. Abadie, R. Abuter, M. Accardo, T. Adler, T. Agocs, P. Antonelli, A. Bohm, C. Bailet, G. Bazin, U. Beckmann, J. Beltran, W. Boland, P. Bourget, R. Brast, Y. Bresson, L. Burtscher, R. Castillo, A. Chelli, C. Cid, J-M Clausse, C. Connot, R. D. Conzelmann, W-C Danchi, M. De Haan, M. Delbo, M. Ebert, E. Elswijk, Y. Fantei, R. Frahm, V. Gamez Rosas, A. Gabasch, A. Gallenne, E. Garces, P. Girard, F. Y. J. Gonte, J. C. Gonzalez Herrera, U. Graser, P. Guajardo, F. Guitton, X. Haubois, J. Hron, N. Hubin, R. Huerta, J. W. Isbell, D. Ives, G. Jakob, A. Jasko, L. Jochum, R. Klein, J. Kragt, G. Kroes, S. Kuindersma, L. Labadie, W. Laun, R. Le Poole, C. Leinert, J-L Lizon, M. Lopez, A. Merand, A. Marcotto, N. Mauclert, T. Maurer, L. H. Mehrgan, J. Meisner, K. Meixner, M. Mellein, L. Mohr, S. Morel, L. Mosoni, R. Navarro, U. Neumann, E. Nussbaum, L. Pallanca, L. Pasquini, I Percheron, J-U Pott, E. Pozna, A. Ridinger, F. Rigal, M. Riquelme, Th Rivinius, R. Roelfsema, R-R Rohloff, S. Rousseau, N. Schuhler, M. Schuil, A. Soulain, P. Stee, C. Stephan, R. ter Horst, N. Tromp, F. Vakili, A. van Duin, J. Vinther, M. Wittkowski, F. Wrhel
Summary: The study aims to characterize the mid-infrared brightness distribution of the inner disk of the young intermediate-mass star HD 163296 from early VLTI/MATISSE observations. The models used account for disk inclination and azimuthal asymmetries, revealing a significant brightness asymmetry in the L-band disk emission. The study proposes a hypothesis where a large-scale vortex may be the physical origin of the asymmetry.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Paola Pinilla, Antonio Garufi, Matias Garate
Summary: The frequency of giant planets may decrease for intermediate-mass stars, and the mechanism behind this phenomenon remains unclear. Through theoretical analysis, it is found that the radial drift velocity of dust particles sharply increases after 1-2 million years around intermediate-mass stars, potentially hindering planet formation. This high radial drift could explain the lack of disk detections around older intermediate-mass stars. Future high-resolution images can help us understand why planets around intermediate-mass stars are rare.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Vanesa Tobon Valencia, Jean-Michel Geffrin, Francois Menard, Julien Milli, Jean-Baptiste Renard, Herve Tortel, Christelle Eyraud, Amelie Litman, Pascal Rannou, Azar Maalouf, Vincent Laur
Summary: This study aims to measure the scattering properties of protoplanetary analog aggregates with different fractal dimensions. Microwave scattering technique was used for the measurements, and the results were compared and discussed. The study found that aggregates with different fractal dimensions have different scattering properties.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Zhaohuan Zhu, Avery Bailey, Enrique Macias, Takayuki Muto, Sean M. Andrews
Summary: Despite difficulties in detecting low-mass planets embedded in protoplanetary discs, a large population of such planets at the Kelvin-Helmholtz contraction phase is suggested by the core-accretion theory. This study uses 1D models and 3D simulations to calculate the envelopes around low-mass cores and derives their thermal fluxes at radio wavelengths. The results show that radio observations can probe the denser envelope within a planet's Hill sphere when the background disc is optically thin.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Jane Huang, Edwin A. Bergin, Jaehan Bae, Myriam Benisty, Sean M. Andrews
Summary: DR Tau is known for its high variability compared to other T Tauri stars. Millimeter interferometry observations reveal the distribution of CO and other substances, showing the presence of a protoplanetary disk, gas envelope, asymmetrical outflow, and spiral arm with clumps. The CO arm is much larger than spiral arms seen in scattered light, highlighting the importance of sensitive molecular imaging for understanding the disk environment. Kinematics and compact emission distribution suggest that (CO)-O-18, SO, DCO+, and H2CO primarily originate from the circumstellar disk. The asymmetry in SO emission may be due to interaction with infalling material or unresolved substructure, indicating a complex environment similar to outbursting FUor and EXor sources, suggesting a link between DR Tau's extreme stellar activity and disk instabilities caused by large-scale infall.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Michihiro Takami, Hans Moritz Gunther, P. Christian Schneider, Tracy L. Beck, Jennifer L. Karr, Youichi Ohyama, Roberto Galvan-Madrid, Taichi Uyama, Marc White, Konstantin Grankin, Deirdre Coffey, Chun-Fan Liu, Misato Fukagawa, Nadine Manset, Wen-Ping Chen, Tae-Soo Pyo, Hsien Shang, Thomas P. Ray, Masaaki Otsuka, Mei-Yin Chou
Summary: We present observations of near-IR [Fe ii] emission from the jets of three active T Tauri stars, RW Aur A, RY Tau, and DG Tau, taken from 2012 to 2021. The velocities and sizes of the jets vary over time, and significant differences in velocities were found in the DG Tau jet between two time periods. The brightness of the individual knots in the emission decreased during our observations. Higher angular resolution observations are needed to better understand the physical nature of these knots.
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
(2023)
Article
Astronomy & Astrophysics
Marshall C. Johnson, Ji Wang, Anusha Pai Asnodkar, Aldo S. Bonomo, B. Scott Gaudi, Thomas Henning, Ilya Ilyin, Engin Keles, Luca Malavolta, Matthias Mallonn, Karan Molaverdikhani, Valerio Nascimbeni, Jennifer Patience, Katja Poppenhaeger, Gaetano Scandariato, Everett Schlawin, Evgenya Shkolnik, Daniela Sicilia, Alessandro Sozzetti, Klaus G. Strassmeier, Christian Veillet, Fei Yan
Summary: Recent observations have shown that the atmospheres of ultrahot Jupiters commonly possess temperature inversions. However, it remains unclear which opacity sources are responsible for these inversions. In this study, the atmosphere of the ultrahot Jupiter KELT-20 b was observed in both transmission and emission to search for molecular agents that could contribute to the temperature inversion. Through testing and analysis, it was found that TiO and CaH can be ruled out as the sources, while more accurate line lists are needed to determine the possibility of VO contributing to the inversion.
ASTRONOMICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
O. Straub, M. Bauboeck, R. Abuter, N. Aimar, P. Amaro Seoane, A. Amorim, J. P. Berger, H. Bonnet, G. Bourdarot, W. Brandner, V. Cardoso, Y. Clenet, Y. Dallilar, R. Davies, P. T. de Zeeuw, J. Dexter, A. Drescher, F. Eisenhauer, N. M. Foerster Schreiber, A. Foschi, P. Garcia, F. Gao, E. Gendron, R. Genzel, S. Gillessen, M. Habibi, X. Haubois, G. Heissel, T. Henning, S. Hippler, M. Horrobin, L. Jochum, L. Jocou, A. Kaufer, P. Kervella, S. Lacour, V. Lapeyrere, J. -B. Le Bouquin, P. Lena, D. Lutz, T. Ott, T. Paumard, K. Perraut, G. Perrin, O. Pfuhl, S. Rabien, D. C. Ribeiro, M. Sadun Bordoni, S. Scheithauer, J. Shangguan, T. Shimizu, J. Stadler, C. Straubmeier, E. Sturm, L. J. Tacconi, F. Vincent, S. von Fellenberg, F. Widmann, E. Wieprecht, E. Wiezorrek, J. Woillez, S. Yazici
Summary: The presence of an intermediate-mass black hole (IMBH) as a binary companion to Sgr A* in the Galactic Centre (GC) is investigated using data from the S2 star. Constraints suggest that IMBH masses > 2000 M-circle dot on orbits with smaller semi-major axes than S2 are largely excluded, and IMBHs with semi-major axes larger than S2 disrupt the S-star cluster in a short time period. Further observations can provide stronger constraints on the properties of IMBHs in the GC.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
M. Lampon, M. Lopez-Puertas, J. Sanz-Forcada, S. Czesla, L. Nortmann, N. Casasayas-Barris, J. Orell-Miquel, A. Sanchez-Lopez, C. Danielski, E. Palle, K. Molaverdikhani, Th. Henning, J. A. Caballero, P. J. Amado, A. Quirrenbach, A. Reiners, I. Ribas
Summary: Characterisation of atmospheres undergoing photo-evaporation is important for understanding planetary formation and evolution. In this study, we characterised the upper atmospheres of several exoplanets through high-resolution observations. By comparing synthetic absorption spectra with observations, we constrained the main parameters of these planets' upper atmospheres and classified them according to their hydrodynamic regime.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Derek Ward-Thompson, Janik Karoly, Kate Pattle, Anthony Whitworth., Jason Kirk., David. Berry, Pierre Bastien, Tao-Chung Ching, Simon Coude, Jihye Hwang, Woojin Kwon, Archana Soam, Jia-Wei Wang, Tetsuo Hasegawa, Shih-Ping Lai, Keping Qiu, Doris Arzoumanian, Tyler L. Bourke, Do-Young Byun, Huei-Ru Vivien Chen, Wen Ping Chen, Mike Chen, Zhiwei Chen, Jungyeon Cho, Minho Choi, Youngwoo Choi, Yunhee Choi, Antonio Chrysostomou, Eun Jung Chung, Sophia Dai, Victor Debattista, James Di Francesco, Pham Ngoc Diep, Yasuo Doi, Hao-Yuan Duan, Yan Duan, Chakali Eswaraiah, Lapo Fanciullo, Jason Fiege, Laura M. Fissel, Erica Franzmann, Per Friberg, Rachel Friesen, Gary Fuller, Ray Furuya, Tim Gledhill, Sarah Graves, Jane Greaves, Matt Griffin, Qilao Gu, Ilseung Han, Saeko Hayashi, Thiem Hoang, Martin Houde, Charles L. H. Hull, Tsuyoshi Inoue, Shu-ichiro Inutsuka, Kazunari Iwasaki, Il-Gyo Jeong, Doug Johnstone, Vera Koenyves, Ji-hyun Kang, Miju Kang, Akimasa Kataoka, Koji Kawabata, Francisca Kemper, Jongsoo Kim, Shinyoung Kim, Gwanjeong Kim, Kyoung Hee Kim, Mi-Ryang Kim, Kee-Tae Kim, Hyosung Kim, Florian Kirchschlager, Masato I. N. Kobayashi, Patrick M. Koch, Takayoshi Kusune, Jungmi Kwon, Kevin Lacaille, Chi-Yan Law, Chang Won Lee, Hyeseung Lee, Yong-Hee Lee, Chin-Fei Lee, Jeong-Eun Lee, Sang-Sung Lee, Di Li, Di Li, Guangxing Li, Hua-bai Li, Sheng-Jun Lin, Hong-Li Liu, Tie Liu, Sheng-Yuan Liu, Junhao Liu, Steven Longmore, Xing Lu, A-Ran Lyo, Steve Mairs, Masafumi Matsumura, Brenda Matthews, Gerald Moriarty-Schieven, Tetsuya Nagata, Fumitaka Nakamura, Hiroyuki Nakanishi, Nguyen Bich Ngoc, Nagayoshi Ohashi, Takashi Onaka, Geumsook Park, Harriet Parsons, Nicolas Peretto, Felix Priestley, Tae-Soo Pyo, Lei Qian, Ramprasad Rao, Jonathan Rawlings, Mark Rawlings, Brendan Retter, John Richer, Andrew Rigby, Sarah Sadavoy, Hiro Saito, Giorgio Savini, Masumichi Seta, Yoshito Shimajiri, Hiroko Shinnaga, Mehrnoosh Tahani, Motohide Tamura, Ya-Wen Tang, Xindi Tang, Kohji Tomisaka, Le Ngoc Tram, Yusuke Tsukamoto, Serena Viti, Hongchi Wang, Jintai Wu, Jinjin Xie, Meng-Zhe Yang, Hsi-Wei Yen, Hyunju Yoo, Jinghua Yuan, Hyeong-Sik Yun, Tetsuya Zenko, Guoyin Zhang, Yapeng Zhang, Chuan-Peng Zhang, Jianjun Zhou, Lei Zhu, Ilse de Looze, Philippe Andre, C. Darren Dowell, David Eden, Stewart Eyres, Sam Falle, Valentin J. M. Le Gouellec, Frederick Poidevin, Jean-Francois Robitaille, Sven van Loo
Summary: We conducted BISTRO Survey observations of the L1495A-B10 region in the Taurus molecular cloud and found a triangular network of dense filaments. Within these filaments, we identified nine starless cores in polarization, and observed that the core-scale magnetic field orientation is nearly perpendicular to the filaments. Furthermore, we discovered a transitional stage in early prestellar evolution and observed the sheet-like structure and its fragmentation into filaments, providing valuable insights into the transition from field-dominated to matter-dominated evolution.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Jamila Pegues, Karin Oberg, Chunhua Qi, Sean M. Andrews, Jane Huang, Charles J. Law, Romane Le Gal, Luca Matra, David J. Wilner
Summary: Protoplanetary disks around Herbig AeBe stars are exciting targets for studying the chemical environments where giant planets form. We conducted a pilot survey of millimeter continuum CO isotopologs and other small molecules in disks around five Herbig AeBe stars and detected or tentatively detected various molecular emissions. The flux ratios between CO 2-1 isotopologs were closest to unity for the Herbig AeBe/F disks, suggesting emitting layers with similar temperatures and more abundant CO relative to the disk dust mass. However, lower detection rates and flux ratios for certain molecules suggest smaller regimes of cold chemistry around the luminous Herbig AeBe/F stars.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Yi Yang, Hauyu Baobab Liu, Takayuki Muto, Jun Hashimoto, Ruobing Dong, Kazuhiro Kanagawa, Munetake Momose, Eiji Akiyama, Yasuhiro Hasegawa, Takashi Tsukagoshi, Mihoko Konishi, Motohide Tamura
Summary: Researching the crescent-like asymmetric dust structures in protoplanetary disks can help us understand the planet formation process.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Charles J. J. Law, Richard Teague, Karin I. I. Oberg, Evan A. A. Rich, Sean M. M. Andrews, Jaehan Bae, Myriam Benisty, Stefano Facchini, Kevin Flaherty, Andrea Isella, Sheng Jin, Jun Hashimoto, Jane Huang, Ryan A. A. Loomis, Feng Long, Carlos E. E. Munoz-Romero, Teresa Paneque-Carreno, Laura M. M. Perez, Chunhua Qi, Kamber R. R. Schwarz, Jochen Stadler, Takashi Tsukagoshi, David J. J. Wilner, Gerrit van der Plas
Summary: High-spatial-resolution observations of CO isotopologue line emission in protoplanetary disks reveal detailed gas structure, including radial and vertical substructures, emission surface heights, and temperature profiles. Observations of CO, (CO)-C-13, and (CO)-O-18 in transition disks provide insights into disk structure and temperature distributions. The derived emission surfaces and temperature models show potential correlations with source characteristics, suggesting the influence of stellar host mass, gas temperature, and disk size on the emitting heights.
ASTROPHYSICAL JOURNAL
(2023)
Article
Chemistry, Physical
Jiao He, Paula Caroline Perez Rickert, Tushar Suhasaria, Orianne Sohier, Tia Baecker, Dimitra Demertzi, Gianfranco Vidali, Thomas K. Henning
Summary: The diffusion of molecules on interstellar grain surfaces is crucial for the molecular complexity in the interstellar medium. A new measurement of CO2 diffusion on non-porous amorphous solid water (np-ASW) surface is presented, providing values for the diffusion energy barrier and pre-exponential factor. Comparison with prior laboratory measurements is discussed.
Article
Astronomy & Astrophysics
B. Tabone, G. Bettoni, E. F. van Dishoeck, A. M. Arabhavi, S. Grant, D. Gasman, Th. Henning, I. Kamp, M. Guedel, P. O. Lagage, T. Ray, B. Vandenbussche, A. Abergel, O. Absil, I. Argyriou, D. Barrado, A. Boccaletti, J. Bouwman, A. Caratti o Garatti, V. Geers, A. M. Glauser, K. Justannont, F. Lahuis, M. Mueller, C. Nehme, G. Olofsson, E. Pantin, S. Scheithauer, C. Waelkens, L. B. F. M. Waters, J. H. Black, V. Christiaens, R. Guadarrama, M. Morales-Calderon, H. Jang, J. Kanwar, N. Pawellek, G. Perotti, A. Perrin, D. Rodgers-Lee, M. Samland, J. Schreiber, K. Schwarz, L. Colina, G. Oestlin, G. Wright
Summary: The amount of carbon that can be delivered to young planets is still uncertain. The chemical characterization of planet-forming disks is important for understanding the diversity and habitability of exoplanets. The James Webb Space Telescope detected abundant hydrocarbons in the disk of a very low-mass star, indicating an active warm hydrocarbon chemistry with a high C/O ratio and important consequences for the composition of forming exoplanets.
Article
Astronomy & Astrophysics
Satoshi Ohashi, Munetake Momose, Akimasa Kataoka, Aya E. Higuchi, Takashi Tsukagoshi, Takahiro Ueda, Claudio Codella, Linda Podio, Tomoyuki Hanawa, Nami Sakai, Hiroshi Kobayashi, Satoshi Okuzumi, Hidekazu Tanaka
Summary: Characterizing the physical properties of dust grains in a protoplanetary disk is critical to understanding the planet formation process. Using high-resolution observations from ALMA, this study presents the properties of a young protoplanetary disk around DG Tau, revealing a thin and smooth disk without substantial substructures. By analyzing the dust surface density, temperature, and grain size distributions, it is found that a higher dust-to-gas mass ratio is necessary to stabilize the disk, and the grain sizes vary in different regions. These findings have implications for the formation of planetesimals.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Nagayoshi Ohashi, John J. J. Tobin, Jes K. K. Jorgensen, Shigehisa Takakuwa, Patrick Sheehan, Yuri Aikawa, Zhi-Yun Li, Leslie W. W. Looney, Jonathan P. P. Williams, Yusuke Aso, Rajeeb Sharma, Jinshi Sai (Insa Choi), Yoshihide Yamato, Jeong-Eun Lee, Kengo Tomida, Hsi-Wei Yen, Frankie J. J. Encalada, Christian Flores, Sacha Gavino, Miyu Kido, Ilseung L. Han, Zhe-Yu Daniel Lin, Suchitra Narayanan, Nguyen Thi Phuong, Alejandro Santamaria-Miranda, Travis J. J. Thieme, Merel L. R. van 't Hoff, Itziar de Gregorio-Monsalvo, Patrick M. Koch, Woojin Kwon, Shih-Ping Lai, Chang Won Lee, Adele Plunkett, Kazuya Saigo, Shingo Hirano, Ka Ho Lam, Shoji Mori
Summary: We present an overview of the Large Program, Early Planet Formation in Embedded Disks (eDisk), conducted with the Atacama Large Millimeter/submillimeter Array (ALMA). The program aims to search for substructures in disks around 12 Class 0 and 7 Class I protostars in nearby star-forming regions. The initial results show that the dust disks around the sample protostars have relatively few distinctive substructures, in contrast to Class II disks, which suggests that substructures quickly develop in disks when the systems evolve from protostars to Class II sources, or that high optical depth of the continuum emission could obscure internal structures.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Zhe-Yu Daniel Lin, Zhi-Yun Li, John J. Tobin, Nagayoshi Ohashi, Jes Kristian Jorgensen, Leslie W. Looney, Yusuke Aso, Shigehisa Takakuwa, Yuri Aikawa, Merel L. R. Van't Hoff, Itziar de Gregorio-Monsalvo, Frankie J. Encalada, Christian Flores, Sacha Gavino, Ilseung Han, Miyu Kido, Patrick M. Koch, Woojin Kwon, Shih-Ping Lai, Chang Won Lee, Jeong-Eun Lee, Nguyen Thi Phuong, Jinshi Sai (Insa Choi), Rajeeb Sharma, Patrick Sheehan, Travis J. Thieme, Jonathan P. Williams, Yoshihide Yamato, Hsi-Wei Yen
Summary: For optically visible Class II protostars, the vertical settling process of dust to the midplane remains unclear. In this study, the edge-on Class I protostar IRAS 04302+2247, known as the Butterfly Star, is analyzed using the Atacama Large Millimeter/submillimeter Array. The results show evidence of an optically thick and geometrically thick disk viewed nearly edge-on, with no rings or gaps observed. The study also reveals the 2D snow surfaces and constrains the CO midplane snow line.
ASTROPHYSICAL JOURNAL
(2023)