A universal spin mass relation for brown dwarfs and planets
While brown dwarfs show similarities to stars early in their lives, their spin evolutions are much more akin to those of planets. We have used light curves from the K2 mission to measure new rotation periods for 18 young brown dwarfs in the Taurus star-forming region. Our sample spans masses from 0....
| Main Authors: | , , , , , |
|---|---|
| Format: | Journal article |
| Published: |
Institute of Physics
2018
|
| _version_ | 1797076476964634624 |
|---|---|
| author | Scholz, A Moore, K Jayawardhana, R Aigrain, S Peterson, D Stelzer, B |
| author_facet | Scholz, A Moore, K Jayawardhana, R Aigrain, S Peterson, D Stelzer, B |
| author_sort | Scholz, A |
| collection | OXFORD |
| description | While brown dwarfs show similarities to stars early in their lives, their spin evolutions are much more akin to those of planets. We have used light curves from the K2 mission to measure new rotation periods for 18 young brown dwarfs in the Taurus star-forming region. Our sample spans masses from 0.02 to 0.08 Moand has been characterized extensively in the past. To search for periods, we utilize three different methods (autocorrelation, periodogram, Gaussian processes). The median period for brown dwarfs with disks is twice as long as for those without (3.1 versus 1.6 days), a signature of rotational braking by the disk, albeit with small numbers. With an overall median period of 1.9 days, brown dwarfs in Taurus rotate slower than their counterparts in somewhat older (3-10 Myr) star-forming regions, consistent with spin-up of the latter due to contraction and angular momentum conservation, a clear sign that disk braking overall is inefficient and/or temporary in this mass domain. We confirm the presence of a linear increase of the typical rotation period as a function of mass in the substellar regime. The rotational velocities, when calculated forward to the age of the solar system, assuming angular momentum conservation, fit the known spin-mass relation for solar system planets and extra-solar planetary-mass objects. This spin-mass trend holds over six orders of magnitude in mass, including objects from several different formation paths. Our result implies that brown dwarfs by and large retain their primordial angular momentum through the first few Myr of their evolution. |
| first_indexed | 2024-03-07T00:04:17Z |
| format | Journal article |
| id | oxford-uuid:770041c5-7707-46e8-9002-9dbb9c048326 |
| institution | University of Oxford |
| last_indexed | 2024-03-07T00:04:17Z |
| publishDate | 2018 |
| publisher | Institute of Physics |
| record_format | dspace |
| spelling | oxford-uuid:770041c5-7707-46e8-9002-9dbb9c0483262022-03-26T20:20:21ZA universal spin mass relation for brown dwarfs and planetsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:770041c5-7707-46e8-9002-9dbb9c048326Symplectic Elements at OxfordInstitute of Physics2018Scholz, AMoore, KJayawardhana, RAigrain, SPeterson, DStelzer, BWhile brown dwarfs show similarities to stars early in their lives, their spin evolutions are much more akin to those of planets. We have used light curves from the K2 mission to measure new rotation periods for 18 young brown dwarfs in the Taurus star-forming region. Our sample spans masses from 0.02 to 0.08 Moand has been characterized extensively in the past. To search for periods, we utilize three different methods (autocorrelation, periodogram, Gaussian processes). The median period for brown dwarfs with disks is twice as long as for those without (3.1 versus 1.6 days), a signature of rotational braking by the disk, albeit with small numbers. With an overall median period of 1.9 days, brown dwarfs in Taurus rotate slower than their counterparts in somewhat older (3-10 Myr) star-forming regions, consistent with spin-up of the latter due to contraction and angular momentum conservation, a clear sign that disk braking overall is inefficient and/or temporary in this mass domain. We confirm the presence of a linear increase of the typical rotation period as a function of mass in the substellar regime. The rotational velocities, when calculated forward to the age of the solar system, assuming angular momentum conservation, fit the known spin-mass relation for solar system planets and extra-solar planetary-mass objects. This spin-mass trend holds over six orders of magnitude in mass, including objects from several different formation paths. Our result implies that brown dwarfs by and large retain their primordial angular momentum through the first few Myr of their evolution. |
| spellingShingle | Scholz, A Moore, K Jayawardhana, R Aigrain, S Peterson, D Stelzer, B A universal spin mass relation for brown dwarfs and planets |
| title | A universal spin mass relation for brown dwarfs and planets |
| title_full | A universal spin mass relation for brown dwarfs and planets |
| title_fullStr | A universal spin mass relation for brown dwarfs and planets |
| title_full_unstemmed | A universal spin mass relation for brown dwarfs and planets |
| title_short | A universal spin mass relation for brown dwarfs and planets |
| title_sort | universal spin mass relation for brown dwarfs and planets |
| work_keys_str_mv | AT scholza auniversalspinmassrelationforbrowndwarfsandplanets AT moorek auniversalspinmassrelationforbrowndwarfsandplanets AT jayawardhanar auniversalspinmassrelationforbrowndwarfsandplanets AT aigrains auniversalspinmassrelationforbrowndwarfsandplanets AT petersond auniversalspinmassrelationforbrowndwarfsandplanets AT stelzerb auniversalspinmassrelationforbrowndwarfsandplanets AT scholza universalspinmassrelationforbrowndwarfsandplanets AT moorek universalspinmassrelationforbrowndwarfsandplanets AT jayawardhanar universalspinmassrelationforbrowndwarfsandplanets AT aigrains universalspinmassrelationforbrowndwarfsandplanets AT petersond universalspinmassrelationforbrowndwarfsandplanets AT stelzerb universalspinmassrelationforbrowndwarfsandplanets |