Two new free-floating or wide-orbit planets from microlensing

  title={Two new free-floating or wide-orbit planets from microlensing},
  author={Przemek Mr{\'o}z and Andrzej Udalski and David P. Bennett and Yoon-Hyun Ryu and Takahiro Sumi and Yossi Shvartzvald and Jan Skowron and R. Poleski and Paweł Pietrukowicz and S. Kozłowski and Michał K. Szymański and Lukasz Wyrzykowski and Igor Soszyński and Krzysztof Ulaczyk and Krzysztof Rybicki and Patryk Iwanek and Michael D. Albrow and S.-J. Chung and A. Gould and C. Han and Kyu-Ha Hwang and Y. K. Jung and In-Gu Shin and Jennifer C. Yee and W.Zang and S. M. Cha and D-J. Kim and H.-W. Kim and S.-L. Kim and C.-U. Lee and D.J. Lee and Y. Lee and B.-G. Park and Richard W. Pogge and Fumio Abe and Richard K. Barry and Aparna Bhattacharya and Ian A.Bond and Martin A Donachie and Akihiko Fukui and Yuki Hirao and Yoshitaka Itow and Kohei Kawasaki and Iona Kondo and Naoki Koshimoto and M. C. A. Li and Yutaka Matsubara and Yasushi Muraki and Shota Miyazaki and Masayuki Nagakane and Cl{\'e}ment Ranc and Nicholas J. Rattenbury and Haruno Suematsu and Denis J. Sullivan and Daisuke Suzuki and Paul J. Tristram and Atsunori Yonehara and Dan Maoz and Shai Kaspi and Matan Friedmann},
  journal={Astronomy \& Astrophysics},
Planet formation theories predict the existence of free-floating planets that have been ejected from their parent systems. Although they emit little or no light, they can be detected during gravitational microlensing events. Microlensing events caused by rogue planets are characterized by very short timescales tE (typically below two days) and small angular Einstein radii θE (up to several μas). Here we present the discovery and characterization of two ultra-short microlensing events identified… Expand

Figures and Tables from this paper

The Scientific Context of WFIRST Microlensing in the 2020s
[abridged] WFIRST is uniquely capable of finding planets with masses as small as Mars at separations comparable to Jupiter, i.e., beyond the current ice lines of their stars. These planets fallExpand
On the detection of free-floating planets through microlensing towards the Magellanic Clouds
  • S. Sajadian
  • Physics
  • Monthly Notices of the Royal Astronomical Society
  • 2021
In this work, we study detecting free-floating planets (FFPs) by microlensing observations towards the Magellanic Clouds (MCs). In comparison to similar events towards the Galactic bulge, an FFP inExpand
WFIRST and EUCLID: Enabling the Microlensing Parallax Measurement from Space
The Wide Field Infrared Survey Telescope (WFIRST) is expected to detect hundreds of free-floating planets, but it will not be able to measure their masses. However, simultaneous microlensingExpand
Probability of simultaneous parallax detection for free-floating planet microlensing events near Galactic Centre
The event rate and the efficiency of mass estimation for free-floating planet (FFP) microlensing events were determined from the simulation of the simultaneous parallax observations by Euclid,Expand
OGLE-2016-BLG-1227L: A Wide-separation Planet from a Very Short-timescale Microlensing Event
We present the analysis of the microlensing event OGLE-2016-BLG-1227. The light curve of this short-duration event appears to be a single-lens event affected by severe finite-source effects. AnalysisExpand
Probing the Survival of Planetary Systems in Globular Clusters with Tidal Disruption Events
Among the growing list of confirmed exoplanets, the number of planets identified in dense star clusters remains sparse. Previous analyses have suggested this may be due in part to dynamicalExpand
Candidate Brown-dwarf Microlensing Events with Very Short Timescales and Small Angular Einstein Radii
Short-timescale microlensing events are likely to be produced by substellar brown dwarfs (BDs), but it is difficult to securely identify BD lenses based on only event timescales $t_{\rm E}$ becauseExpand
Survivability of planetary systems in young and dense star clusters
Aims. We perform a simulation using the Astrophysical Multipurpose Software Environment of the Orion Trapezium star cluster in which the evolution of the stars and the dynamics of planetary systemsExpand
Spitzer Microlensing Parallax Reveals Two Isolated Stars in the Galactic Bulge
We report the mass and distance measurements of two single-lens events from the 2017 $\textit {Spitzer}$ microlensing campaign. The ground-based observations yield the detection of finite-sourceExpand
Modelling the projected separation of microlensing events using systematic time-series feature engineering
A workflow for identifying characteristics of light curves to estimate the projected separation from microlensing observations and an implementation of Bayesian Linear Regression on polynomial combinations of these seven light curve features, which computes probability distributions for recovered planet–star separations. Expand


No large population of unbound or wide-orbit Jupiter-mass planets
A sample of microlensing events six times larger than that of ref. 11 is analysed, finding no excess of events with timescales in this range, with a 95 per cent upper limit on the frequency of Jupiter-mass free-floating or wide-orbit planets of 0.25 planets per main-sequence star. Expand
A Neptune-mass Free-floating Planet Candidate Discovered by Microlensing Surveys
Current microlensing surveys are sensitive to free-floating planets down to Earth-mass objects. All published microlensing events attributed to unbound planets were identified based on their shortExpand
Unbound or distant planetary mass population detected by gravitational microlensing
  • T. K. D. P. I. A. F. C. S. A. K. J. B. Y. P. M. A. W. Sumi Kamiya Bennett Bond Abe Botzler Fukui Furusaw, T. Sumi, +38 authors K. Ulaczyk
  • Physics, Medicine
  • Nature
  • 2011
The discovery of a population of unbound or distant Jupiter-mass objects is reported, which are almost twice as common as main-sequence stars, based on two years of gravitational microlensing survey observations towards the Galactic Bulge. Expand
The Demographics of Rocky Free-Floating Planets and their Detectability by WFIRST
Planets are thought to form via accretion from a remnant disk of gas and solids around a newly formed star. During this process material in the disk either remains bound to the star as part of eitherExpand
Free-floating planets from core accretion theory: microlensing predictions
We calculate the microlensing event rate and typical time-scales for the free-floating planet (FFP) population that is predicted by the core accretion theory of planet formation. The event rate isExpand
Microlensing by Kuiper, Oort, and Free-Floating Planets
Microlensing is generally thought to probe planetary systems only out to a few Einstein radii. Microlensing events generated by bound planets beyond about 10 Einstein radii generally do not yield anyExpand
Triple Microlens OGLE-2008-BLG-092L: Binary Stellar System with a Circumprimary Uranus-type Planet
We present the gravitational microlensing discovery of a 4 M_Uranus planet that orbits a 0.7 M_Sun star at ~18 AU. This is the first known analog of Uranus. Similar planets, i.e., cold ice-giants,Expand
Can the Masses of Isolated Planetary-mass Gravitational Lenses be Measured by Terrestrial Parallax?
Recently Sumi et al. reported evidence for a large population of planetary-mass objects (PMOs) that are either unbound or orbit host stars in orbits ≥10 AU. Their result was deduced from theExpand
Direct imaging searches have begun to detect planetary and brown dwarf companions and to place constraints on the presence of giant planets at large separations from their host star. This work helpsExpand
We find that free-floating planets can remain bound to an open cluster for much longer than was previously calculated: of the order of the cluster half-mass relaxation timescale as opposed to theExpand