Disks around Young Planetary-mass Objects: Ultradeep Spitzer Imaging of NGC 1333
We report on a sensitive infrared search for disks around isolated young planetary-mass objects (PMOs) in the NGC 1333 cluster, by stacking 70 Spitzer/IRAC frames at 3.6 and 4.5 μ m. Our coadded images go >2.3 mag deeper than single-epoch frames, and cover 50 brown dwarfs, 15 of which have M9 or...
| 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/acc65d |
| _version_ | 1797697258653745152 |
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| author | Aleks Scholz Koraljka Muzic Ray Jayawardhana Victor Almendros-Abad Isaac Wilson |
| author_facet | Aleks Scholz Koraljka Muzic Ray Jayawardhana Victor Almendros-Abad Isaac Wilson |
| author_sort | Aleks Scholz |
| collection | DOAJ |
| description | We report on a sensitive infrared search for disks around isolated young planetary-mass objects (PMOs) in the NGC 1333 cluster, by stacking 70 Spitzer/IRAC frames at 3.6 and 4.5 μ m. Our coadded images go >2.3 mag deeper than single-epoch frames, and cover 50 brown dwarfs, 15 of which have M9 or later spectral types. Spectral types >M9 correspond to masses in the giant-planet domain, i.e., near or below the deuterium-burning limit of 0.015 M _⊙ . Five of the 12 PMOs show definitive evidence of excess, implying a disk fraction of 42%, albeit with a large statistical uncertainty given the small sample. Comparing with measurements for higher-mass objects, the disk fraction does not decline substantially with decreasing mass in the substellar domain, consistent with previous findings. Thus, free-floating PMOs have the potential to form their own miniature planetary systems. We note that only one of the six lowest-mass objects in NGC 1333, with spectral type L0 or later, has a confirmed disk. Reviewing the literature, we find that the lowest-mass free-floating objects with firm disk detections have masses ∼0.01 M _⊙ (or ∼10 M _Jup ). It is not clear yet whether even lower-mass objects harbor disks. If not, it may indicate that ∼10 M _Jup is the lower-mass limit for objects that form like stars. Our disk-detection experiment on deep Spitzer images paves the way for studies with JWST at longer wavelengths and higher sensitivity, which will further explore disk prevalence and formation of free-floating PMOs. |
| first_indexed | 2024-03-12T03:37:47Z |
| format | Article |
| id | doaj.art-73db79a5225449079315efb7b62c70cf |
| institution | Directory Open Access Journal |
| issn | 1538-3881 |
| language | English |
| last_indexed | 2024-03-12T03:37:47Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astronomical Journal |
| spelling | doaj.art-73db79a5225449079315efb7b62c70cf2023-09-03T13:07:52ZengIOP PublishingThe Astronomical Journal1538-38812023-01-01165519610.3847/1538-3881/acc65dDisks around Young Planetary-mass Objects: Ultradeep Spitzer Imaging of NGC 1333Aleks Scholz0https://orcid.org/0000-0001-8993-5053Koraljka Muzic1https://orcid.org/0000-0002-7989-2595Ray Jayawardhana2https://orcid.org/0000-0001-5349-6853Victor Almendros-Abad3Isaac Wilson4School of Physics & Astronomy, University of St Andrews , North Haugh, St Andrews KY16 9SS, UK ; as110@st-andrews.ac.ukCENTRA, Faculdade de Ciências, Universidade de Lisboa , Ed. C8, Campo Grande, P-1749-016 Lisboa, Portugal; Faculdade de Engenharia, Universidade do Porto , Rua Dr. Roberto Frias, 4200-465 Porto, PortugalDepartment of Astronomy, Cornell University , Ithaca, NY 14853, USACENTRA, Faculdade de Ciências, Universidade de Lisboa , Ed. C8, Campo Grande, P-1749-016 Lisboa, PortugalPalomar Observatory, California Institute of Technology , Pasadena, CA, USAWe report on a sensitive infrared search for disks around isolated young planetary-mass objects (PMOs) in the NGC 1333 cluster, by stacking 70 Spitzer/IRAC frames at 3.6 and 4.5 μ m. Our coadded images go >2.3 mag deeper than single-epoch frames, and cover 50 brown dwarfs, 15 of which have M9 or later spectral types. Spectral types >M9 correspond to masses in the giant-planet domain, i.e., near or below the deuterium-burning limit of 0.015 M _⊙ . Five of the 12 PMOs show definitive evidence of excess, implying a disk fraction of 42%, albeit with a large statistical uncertainty given the small sample. Comparing with measurements for higher-mass objects, the disk fraction does not decline substantially with decreasing mass in the substellar domain, consistent with previous findings. Thus, free-floating PMOs have the potential to form their own miniature planetary systems. We note that only one of the six lowest-mass objects in NGC 1333, with spectral type L0 or later, has a confirmed disk. Reviewing the literature, we find that the lowest-mass free-floating objects with firm disk detections have masses ∼0.01 M _⊙ (or ∼10 M _Jup ). It is not clear yet whether even lower-mass objects harbor disks. If not, it may indicate that ∼10 M _Jup is the lower-mass limit for objects that form like stars. Our disk-detection experiment on deep Spitzer images paves the way for studies with JWST at longer wavelengths and higher sensitivity, which will further explore disk prevalence and formation of free-floating PMOs.https://doi.org/10.3847/1538-3881/acc65dBrown dwarfs |
| spellingShingle | Aleks Scholz Koraljka Muzic Ray Jayawardhana Victor Almendros-Abad Isaac Wilson Disks around Young Planetary-mass Objects: Ultradeep Spitzer Imaging of NGC 1333 The Astronomical Journal Brown dwarfs |
| title | Disks around Young Planetary-mass Objects: Ultradeep Spitzer Imaging of NGC 1333 |
| title_full | Disks around Young Planetary-mass Objects: Ultradeep Spitzer Imaging of NGC 1333 |
| title_fullStr | Disks around Young Planetary-mass Objects: Ultradeep Spitzer Imaging of NGC 1333 |
| title_full_unstemmed | Disks around Young Planetary-mass Objects: Ultradeep Spitzer Imaging of NGC 1333 |
| title_short | Disks around Young Planetary-mass Objects: Ultradeep Spitzer Imaging of NGC 1333 |
| title_sort | disks around young planetary mass objects ultradeep spitzer imaging of ngc 1333 |
| topic | Brown dwarfs |
| url | https://doi.org/10.3847/1538-3881/acc65d |
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