JWST’s Sharper View of EX Lup: Cold Water from Ice Sublimation during Accretion Outbursts
The unstable accretion phases during pre-main-sequence evolution of T Tauri stars produce variable irradiation and heating of planet-forming regions. A strong accretion outburst was observed with Spitzer-InfraRed Spectrograph in 2008 in EX Lup, the prototype of EXor variables, and found to increase...
Saved in:
| Main Authors: | , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2025-01-01
|
| Series: | The Astrophysical Journal Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/2041-8213/adcab8 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849722263573626880 |
|---|---|
| author | Sarah A. Smith Carlos E. Romero-Mirza Andrea Banzatti Christian Rab Péter Ábrahám Ágnes Kóspál Rik Claes Carlo F. Manara Karin I. Öberg Jeroen Bouwman Fernando Cruz-Sáenz de Miera Joel D. Green |
| author_facet | Sarah A. Smith Carlos E. Romero-Mirza Andrea Banzatti Christian Rab Péter Ábrahám Ágnes Kóspál Rik Claes Carlo F. Manara Karin I. Öberg Jeroen Bouwman Fernando Cruz-Sáenz de Miera Joel D. Green |
| author_sort | Sarah A. Smith |
| collection | DOAJ |
| description | The unstable accretion phases during pre-main-sequence evolution of T Tauri stars produce variable irradiation and heating of planet-forming regions. A strong accretion outburst was observed with Spitzer-InfraRed Spectrograph in 2008 in EX Lup, the prototype of EXor variables, and found to increase the mid-infrared water and OH emission and decrease organic emission, suggesting large chemical changes. We present here two JWST-MIRI epochs of quiescent EX Lup in 2022 and 2023 obtained over a decade after the 2008 outburst and several months after a moderate burst in 2022. With JWST’s sharper spectral view, we can now analyze water emission as a function of temperature in the two MIRI epochs and, approximately, also in the previous Spitzer epochs. This new analysis shows a strong cold water vapor “burst” in low-energy lines during the 2008 outburst, which we consider clear evidence for enhanced ice sublimation due to a recession of the snowline, as found in protostellar envelopes. JWST shows that EX Lup still has an unusually strong emission from cold water in comparison to other T Tauri disks, suggesting >10 yr long freeze-out timescales in the inner disk surface. EX Lup demonstrates that outbursts can significantly change the observed organic-to-water ratios and increase the cold water reservoir, providing chemical signatures to study the recent accretion history of disks. This study provides an unprecedented demonstration of the chemical evolution triggered by accretion outbursts in the class II phase and of the high potential of time-domain experiments to reveal processes that may have fundamental implications on planet-forming bodies near the snowline. |
| format | Article |
| id | doaj-art-e439a37c386e48129f351d302f94f4b4 |
| institution | DOAJ |
| issn | 2041-8205 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal Letters |
| spelling | doaj-art-e439a37c386e48129f351d302f94f4b42025-08-20T03:11:22ZengIOP PublishingThe Astrophysical Journal Letters2041-82052025-01-019842L5110.3847/2041-8213/adcab8JWST’s Sharper View of EX Lup: Cold Water from Ice Sublimation during Accretion OutburstsSarah A. Smith0https://orcid.org/0009-0008-5780-4217Carlos E. Romero-Mirza1https://orcid.org/0000-0001-7152-9794Andrea Banzatti2https://orcid.org/0000-0003-4335-0900Christian Rab3https://orcid.org/0000-0003-1817-6576Péter Ábrahám4https://orcid.org/0000-0001-6015-646XÁgnes Kóspál5https://orcid.org/0000-0001-7157-6275Rik Claes6https://orcid.org/0000-0001-8194-4238Carlo F. Manara7https://orcid.org/0000-0003-3562-262XKarin I. Öberg8https://orcid.org/0000-0001-8798-1347Jeroen Bouwman9https://orcid.org/0000-0003-4757-2500Fernando Cruz-Sáenz de Miera10https://orcid.org/0000-0002-4283-2185Joel D. Green11https://orcid.org/0000-0003-1665-5709Department of Physics, Texas State University , 749 N. Comanche St., San Marcos, TX 78666, USA ; banzatti@txstate.eduCenter for Astrophysics ∣ Harvard & Smithsonian , Cambridge, MA 02138, USADepartment of Physics, Texas State University , 749 N. Comanche St., San Marcos, TX 78666, USA ; banzatti@txstate.eduUniversity Observatory , Faculty of Physics, Ludwig-Maximilians-Universität München, Scheinerstr. 1, D-81679 Munich, Germany; Max-Planck-Institut für extraterrestrische Physik , Giessenbachstrasse 1, D-85748 Garching, GermanyKonkoly Observatory , HUN-REN Research Centre for Astronomy and Earth Sciences, MTA Centre of Excellence, Konkoly-Thege Miklós út 15-17, 1121 Budapest, Hungary; Institute of Physics and Astronomy, ELTE Eötvös Loránd University , Pázmány Péter sétány 1/A, 1117 Budapest, Hungary; Department of Astrophysics, University of Vienna , Türkenschanzstr. 17, A-1180 Vienna, AustriaKonkoly Observatory , HUN-REN Research Centre for Astronomy and Earth Sciences, MTA Centre of Excellence, Konkoly-Thege Miklós út 15-17, 1121 Budapest, Hungary; Institute of Physics and Astronomy, ELTE Eötvös Loránd University , Pázmány Péter sétány 1/A, 1117 Budapest, Hungary; Max Planck Institute for Astronomy , Königstuhl 17, 69117 Heidelberg, GermanyEuropean Southern Observatory , Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, GermanyEuropean Southern Observatory , Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, GermanyCenter for Astrophysics , Harvard & Smithsonian, 60 Garden St., Cambridge, MA 02138, USAMax Planck Institute for Astronomy , Königstuhl 17, 69117 Heidelberg, GermanyKonkoly Observatory , HUN-REN Research Centre for Astronomy and Earth Sciences, MTA Centre of Excellence, Konkoly-Thege Miklós út 15-17, 1121 Budapest, Hungary; Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse , UT3-PS, OMP, CNRS, 9 av. du Colonel-Roche, 31028 Toulouse Cedex 4, FranceSpace Telescope Science Institute , 3700 San Martin Dr., Baltimore, MD 02138, USAThe unstable accretion phases during pre-main-sequence evolution of T Tauri stars produce variable irradiation and heating of planet-forming regions. A strong accretion outburst was observed with Spitzer-InfraRed Spectrograph in 2008 in EX Lup, the prototype of EXor variables, and found to increase the mid-infrared water and OH emission and decrease organic emission, suggesting large chemical changes. We present here two JWST-MIRI epochs of quiescent EX Lup in 2022 and 2023 obtained over a decade after the 2008 outburst and several months after a moderate burst in 2022. With JWST’s sharper spectral view, we can now analyze water emission as a function of temperature in the two MIRI epochs and, approximately, also in the previous Spitzer epochs. This new analysis shows a strong cold water vapor “burst” in low-energy lines during the 2008 outburst, which we consider clear evidence for enhanced ice sublimation due to a recession of the snowline, as found in protostellar envelopes. JWST shows that EX Lup still has an unusually strong emission from cold water in comparison to other T Tauri disks, suggesting >10 yr long freeze-out timescales in the inner disk surface. EX Lup demonstrates that outbursts can significantly change the observed organic-to-water ratios and increase the cold water reservoir, providing chemical signatures to study the recent accretion history of disks. This study provides an unprecedented demonstration of the chemical evolution triggered by accretion outbursts in the class II phase and of the high potential of time-domain experiments to reveal processes that may have fundamental implications on planet-forming bodies near the snowline.https://doi.org/10.3847/2041-8213/adcab8Circumstellar disksProtoplanetary disksMolecular spectroscopyExoplanet formationStellar flaresPre-main sequence stars |
| spellingShingle | Sarah A. Smith Carlos E. Romero-Mirza Andrea Banzatti Christian Rab Péter Ábrahám Ágnes Kóspál Rik Claes Carlo F. Manara Karin I. Öberg Jeroen Bouwman Fernando Cruz-Sáenz de Miera Joel D. Green JWST’s Sharper View of EX Lup: Cold Water from Ice Sublimation during Accretion Outbursts The Astrophysical Journal Letters Circumstellar disks Protoplanetary disks Molecular spectroscopy Exoplanet formation Stellar flares Pre-main sequence stars |
| title | JWST’s Sharper View of EX Lup: Cold Water from Ice Sublimation during Accretion Outbursts |
| title_full | JWST’s Sharper View of EX Lup: Cold Water from Ice Sublimation during Accretion Outbursts |
| title_fullStr | JWST’s Sharper View of EX Lup: Cold Water from Ice Sublimation during Accretion Outbursts |
| title_full_unstemmed | JWST’s Sharper View of EX Lup: Cold Water from Ice Sublimation during Accretion Outbursts |
| title_short | JWST’s Sharper View of EX Lup: Cold Water from Ice Sublimation during Accretion Outbursts |
| title_sort | jwst s sharper view of ex lup cold water from ice sublimation during accretion outbursts |
| topic | Circumstellar disks Protoplanetary disks Molecular spectroscopy Exoplanet formation Stellar flares Pre-main sequence stars |
| url | https://doi.org/10.3847/2041-8213/adcab8 |
| work_keys_str_mv | AT sarahasmith jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT carloseromeromirza jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT andreabanzatti jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT christianrab jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT peterabraham jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT agneskospal jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT rikclaes jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT carlofmanara jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT karinioberg jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT jeroenbouwman jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT fernandocruzsaenzdemiera jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts AT joeldgreen jwstssharperviewofexlupcoldwaterfromicesublimationduringaccretionoutbursts |