Next-Gen modelling for high-precision exoplanet microlensing surveys
Lead Research Organisation:
University of Manchester
Department Name: Physics and Astronomy
Abstract
The abundance of exoplanets not bound to any star, floating in the interstellar medium, known as
free floating planets (FFPs) is currently poorly constrained. Direct imaging has provided several
confirmed FFPs, but does not allow us to extract FFP statistics. Via the gravitational microlensing
method, we are more likely to find these illusive objects due to the methods invariability to the lens
flux. Nonetheless, microlensing surveys have also provided only a handful of candidates. This is due
to the comparatively small masses of FFPs, on similar scales to planet masses, and the
correspondingly short timescale of microlensing events. Upcoming surveys such as by the Large
Synoptic Survey Telescope (LSST) and the Wide Field Infrared Survey Telescope (WFIRST) could
provide unprecedented detail on the galactic population of FFPs and also allow for properties such as
FFP mass measurements to be made, also providing insight into planetary formation. To this end, the
project will focus on developing an FFP search strategy for the LSST and WFIRST. This will involve
developing more a more rigorous calculation of the microlensing optical depth, as well as
investigating the potential for FFP mass measurements given the technology of the respective
telescopes.
free floating planets (FFPs) is currently poorly constrained. Direct imaging has provided several
confirmed FFPs, but does not allow us to extract FFP statistics. Via the gravitational microlensing
method, we are more likely to find these illusive objects due to the methods invariability to the lens
flux. Nonetheless, microlensing surveys have also provided only a handful of candidates. This is due
to the comparatively small masses of FFPs, on similar scales to planet masses, and the
correspondingly short timescale of microlensing events. Upcoming surveys such as by the Large
Synoptic Survey Telescope (LSST) and the Wide Field Infrared Survey Telescope (WFIRST) could
provide unprecedented detail on the galactic population of FFPs and also allow for properties such as
FFP mass measurements to be made, also providing insight into planetary formation. To this end, the
project will focus on developing an FFP search strategy for the LSST and WFIRST. This will involve
developing more a more rigorous calculation of the microlensing optical depth, as well as
investigating the potential for FFP mass measurements given the technology of the respective
telescopes.
Organisations
People |
ORCID iD |
| Eamonn Kerins (Primary Supervisor) | |
| David Specht (Student) |
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| ST/S505572/1 | 01/10/2018 | 30/09/2022 | |||
| 2107389 | Studentship | ST/S505572/1 | 01/10/2018 | 31/03/2022 | David Specht |
| Description | Next generation microlensing simulations have been employed to verify the accuracy of current model of Galactic structure, finding good agreement with some discrepancy in the Galactic bulge/bar region. Similar microlensing simulations have been used to predict the amount of Earth and Jupiter mass free-floating planets (FFPs) which a joint survey by the upcoming Euclid and NGRST space telescopes could detect. These numbers specifically refer to FFPs for which we could reasonably calculate a planetary mass and hence provide bounds on the occurrence rates of FFPs in our Galaxy. An exoplanet has been discovered from Kepler's K2C9 microlensing campaign, which is of particular importance as this has been the first microlensing exoplanet discovery from a space based observatory. Ground based data was later used to provide extra information about the exoplanet. This discovery proves that space based microlensing surveys such as by Euclid and NGRST are feasible. |
| Exploitation Route | The mabuls-2 microlensing tool can be used by the research community and is available at http://www.mabuls.net/ |
| Sectors | Education |
| Title | Mabuls-2 |
| Description | Allows the user to generate gravitational microlensing parameter maps for optical depth, micolensing timescale, rate per source star and rate per square degree, of the galaxy centred around (l,b) = (0,0) in user specified Johnson-Cousins wavelength bands. |
| Type Of Technology | Webtool/Application |
| Year Produced | 2020 |
| Impact | As the software has only been online since mid 2020, there is no published work utilising its output, although there is ongoing research currently using it. |
| URL | http://www.mabuls.net/ |