UV-optical Emission of AB Aur b Is Consistent with Scattered Stellar Light
The proposed protoplanet AB Aur b is a spatially concentrated emission source imaged in the millimeter-wavelength disk gap of the Herbig Ae/Be star AB Aur. Its near-infrared spectrum and absence of strong polarized light have been interpreted as evidence supporting the protoplanet interpretation. Ho...
| Main Authors: | , , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
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IOP Publishing
2023-01-01
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| Series: | The Astronomical Journal |
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| Online Access: | https://doi.org/10.3847/1538-3881/acf9ec |
| _version_ | 1827775544421253120 |
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| author | Yifan Zhou Brendan P. Bowler Haifeng Yang Aniket Sanghi Gregory J. Herczeg Adam L. Kraus Jaehan Bae Feng Long Katherine B. Follette Kimberly Ward-Duong Zhaohuan Zhu Lauren Biddle Laird M. Close Lillian Yushu Jiang Ya-Lin Wu |
| author_facet | Yifan Zhou Brendan P. Bowler Haifeng Yang Aniket Sanghi Gregory J. Herczeg Adam L. Kraus Jaehan Bae Feng Long Katherine B. Follette Kimberly Ward-Duong Zhaohuan Zhu Lauren Biddle Laird M. Close Lillian Yushu Jiang Ya-Lin Wu |
| author_sort | Yifan Zhou |
| collection | DOAJ |
| description | The proposed protoplanet AB Aur b is a spatially concentrated emission source imaged in the millimeter-wavelength disk gap of the Herbig Ae/Be star AB Aur. Its near-infrared spectrum and absence of strong polarized light have been interpreted as evidence supporting the protoplanet interpretation. However, the complex scattered-light structures in the AB Aur disk pose challenges in resolving the emission source and interpreting the true nature of AB Aur b. We present new images of the AB Aur system obtained using the Hubble Space Telescope Wide Field Camera 3 in the ultraviolet (UV) and optical bands. AB Aur b and the known disk spirals are recovered in the F336W, F410M, and F645N bands. The spectral energy distribution of AB Aur b shows absorption in the Balmer jump, mimicking that of early-type stars. By comparing the colors of AB Aur b to those of the host star, the disk spirals, and predictions from scattered light and self-luminous models, we find that the emission from AB Aur b is inconsistent with planetary photospheric or accretion shock models. Instead, it is consistent with those measured in the circumstellar disks that trace scattered light. We conclude that the UV and visible emission from AB Aur b does not necessitate the presence of a protoplanet. We synthesize observational constraints on AB Aur b and discuss inconsistent interpretations among different data sets. Considering the significance of the AB Aur b discovery, we advocate for further observational evidence to verify its planetary nature. |
| first_indexed | 2024-03-11T13:51:58Z |
| format | Article |
| id | doaj.art-2961a4de002b4b63a6a40fd2441d607b |
| institution | Directory Open Access Journal |
| issn | 1538-3881 |
| language | English |
| last_indexed | 2024-03-11T13:51:58Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astronomical Journal |
| spelling | doaj.art-2961a4de002b4b63a6a40fd2441d607b2023-11-02T08:27:12ZengIOP PublishingThe Astronomical Journal1538-38812023-01-01166622010.3847/1538-3881/acf9ecUV-optical Emission of AB Aur b Is Consistent with Scattered Stellar LightYifan Zhou0https://orcid.org/0000-0003-2969-6040Brendan P. Bowler1https://orcid.org/0000-0003-2649-2288Haifeng Yang2https://orcid.org/0000-0002-8537-6669Aniket Sanghi3https://orcid.org/0000-0002-1838-4757Gregory J. Herczeg4https://orcid.org/0000-0002-7154-6065Adam L. Kraus5https://orcid.org/0000-0001-9811-568XJaehan Bae6https://orcid.org/0000-0001-7258-770XFeng Long7https://orcid.org/0000-0002-7607-719XKatherine B. Follette8https://orcid.org/0000-0002-7821-0695Kimberly Ward-Duong9https://orcid.org/0000-0002-4479-8291Zhaohuan Zhu10https://orcid.org/0000-0003-3616-6822Lauren Biddle11https://orcid.org/0000-0003-2646-3727Laird M. Close12https://orcid.org/0000-0002-2167-8246Lillian Yushu Jiang13https://orcid.org/0000-0003-4006-102XYa-Lin Wu14https://orcid.org/0000-0002-4392-1446Department of Astronomy, The University of Texas at Austin , 2515 Speedway, Stop C1400, Austin, TX 78712, USA ; yzhou@virginia.edu; Department of Astronomy, University of Virginia , 530 McCormick Rd, Charlottesville, VA 22904, USADepartment of Astronomy, The University of Texas at Austin , 2515 Speedway, Stop C1400, Austin, TX 78712, USA ; yzhou@virginia.eduKavli Institute for Astronomy and Astrophysics, Peking University , Yi He Yuan Lu 5, Haidian Qu, Beijing 100871, People's Republic of ChinaDepartment of Astronomy, The University of Texas at Austin , 2515 Speedway, Stop C1400, Austin, TX 78712, USA ; yzhou@virginia.eduKavli Institute for Astronomy and Astrophysics, Peking University , Yi He Yuan Lu 5, Haidian Qu, Beijing 100871, People's Republic of ChinaDepartment of Astronomy, The University of Texas at Austin , 2515 Speedway, Stop C1400, Austin, TX 78712, USA ; yzhou@virginia.eduDepartment of Astronomy, University of Florida , Gainesville, FL 32611, USADepartment of Planetary Science/Lunar and Planetary Laboratory, The University of Arizona , Tucson, AZ 85721, USADepartment of Physics and Astronomy, Amherst College , Amherst, MA 01003, USADepartment of Astronomy, Smith College , Northampton, MA 01063, USADepartment of Physics and Astronomy, University of Nevada , Las Vegas, NV 89154, USADepartment of Astronomy, The University of Texas at Austin , 2515 Speedway, Stop C1400, Austin, TX 78712, USA ; yzhou@virginia.eduDepartment of Astronomy/Steward Observatory, University of Arizona , Tucson, AZ 85719, USADepartment of Astronomy, The University of Texas at Austin , 2515 Speedway, Stop C1400, Austin, TX 78712, USA ; yzhou@virginia.eduDepartment of Physics, National Taiwan Normal University , Taipei 116, Taiwan; Center of Astronomy and Gravitation, National Taiwan Normal University , Taipei 116, TaiwanThe proposed protoplanet AB Aur b is a spatially concentrated emission source imaged in the millimeter-wavelength disk gap of the Herbig Ae/Be star AB Aur. Its near-infrared spectrum and absence of strong polarized light have been interpreted as evidence supporting the protoplanet interpretation. However, the complex scattered-light structures in the AB Aur disk pose challenges in resolving the emission source and interpreting the true nature of AB Aur b. We present new images of the AB Aur system obtained using the Hubble Space Telescope Wide Field Camera 3 in the ultraviolet (UV) and optical bands. AB Aur b and the known disk spirals are recovered in the F336W, F410M, and F645N bands. The spectral energy distribution of AB Aur b shows absorption in the Balmer jump, mimicking that of early-type stars. By comparing the colors of AB Aur b to those of the host star, the disk spirals, and predictions from scattered light and self-luminous models, we find that the emission from AB Aur b is inconsistent with planetary photospheric or accretion shock models. Instead, it is consistent with those measured in the circumstellar disks that trace scattered light. We conclude that the UV and visible emission from AB Aur b does not necessitate the presence of a protoplanet. We synthesize observational constraints on AB Aur b and discuss inconsistent interpretations among different data sets. Considering the significance of the AB Aur b discovery, we advocate for further observational evidence to verify its planetary nature.https://doi.org/10.3847/1538-3881/acf9ecHubble Space TelescopeExoplanetsProtoplanetary disksDirect imagingHST photometryUltraviolet color |
| spellingShingle | Yifan Zhou Brendan P. Bowler Haifeng Yang Aniket Sanghi Gregory J. Herczeg Adam L. Kraus Jaehan Bae Feng Long Katherine B. Follette Kimberly Ward-Duong Zhaohuan Zhu Lauren Biddle Laird M. Close Lillian Yushu Jiang Ya-Lin Wu UV-optical Emission of AB Aur b Is Consistent with Scattered Stellar Light The Astronomical Journal Hubble Space Telescope Exoplanets Protoplanetary disks Direct imaging HST photometry Ultraviolet color |
| title | UV-optical Emission of AB Aur b Is Consistent with Scattered Stellar Light |
| title_full | UV-optical Emission of AB Aur b Is Consistent with Scattered Stellar Light |
| title_fullStr | UV-optical Emission of AB Aur b Is Consistent with Scattered Stellar Light |
| title_full_unstemmed | UV-optical Emission of AB Aur b Is Consistent with Scattered Stellar Light |
| title_short | UV-optical Emission of AB Aur b Is Consistent with Scattered Stellar Light |
| title_sort | uv optical emission of ab aur b is consistent with scattered stellar light |
| topic | Hubble Space Telescope Exoplanets Protoplanetary disks Direct imaging HST photometry Ultraviolet color |
| url | https://doi.org/10.3847/1538-3881/acf9ec |
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