J/A+A/623/A85 Evolutionary models of cold and low-mass planets (Linder, 2019)
Evolutionary models of cold and low-mass planets:
cooling curves, magnitudes, and detectability.
Linder E.F., Mordasini C., Molliere P., Marleau G.-D., Malik M.,
Quanz S.P., Meyer M.R.
<Astron. Astrophys. 623, A85 (2019)>
=2019A&A...623A..85L 2019A&A...623A..85L (SIMBAD/NED BibCode)
ADC_Keywords: Models, evolutionary ; Photometry
Keywords: planets and satellites: physical evolution -
planets and satellites: atmospheres -
planets and satellites: detection
Abstract:
Future instruments like the Near Infrared Camera (NIRCam) and the Mid
Infrared Instrument (MIRI) on the James Webb Space Telescope (JWST) or
the Mid-Infrared E-ELT Imager and Spectrograph (METIS) at the European
Extremely Large Telescope (E-ELT) will be able to image exoplanets
that are too faint (because they have a low mass, and hence a small
size or low effective temperature) for current direct imaging
instruments. On the theoretical side, core accretion formation models
predict a significant population of low-mass and/or cool planets at
orbital distances of ∼10-100au.
Evolutionary models predicting the planetary intrinsic luminosity as a
function of time have traditionally concentrated on gas-dominated
giant planets. We extend these cooling curves to Saturnian and
Neptunian planets.
We simulated the cooling of isolated core-dominated and gas giant
planets with masses of 5M{earth} to 2M{jup}. The planets consist
of a core made of iron, silicates, and ices surrounded by a H/He
envelope, similar to the ice giants in the solar system. The
luminosity includes the contribution from the cooling and contraction
of the core and of the H/He envelope, as well as radiogenic decay. For
the atmosphere we used grey, AMES-Cond, petitCODE, and HELIOS models.
We considered solar and non-solar metallicities as well as cloud-free
and cloudy atmospheres. The most important initial conditions, namely
the core-to-envelope ratio and the initial (i.e. post formation)
luminosity are taken from planet formation simulations based on the
core accretion paradigm.
We first compare our cooling curves for Uranus, Neptune, Jupiter,
Saturn, GJ 436b, and a 5M{earth} planet with a 1% H/He envelope with
other evolutionary models. We then present the temporal evolution of
planets with masses between 5M{earth} and 2M{jup} in terms of
their luminosity, effective temperature, radius, and entropy. We
discuss the impact of different post formation entropies. For the
different atmosphere types and initial conditions, magnitudes in
various filter bands between 0.9 and 30 micrometer wavelength are
provided.
Using blackbody fluxes and non-grey spectra, we estimate the
detectability of such planets with JWST. We found that a
20(100)M{earth} planet can be detected with JWST in the background
limit up to an age of about 10(100)Myr with NIRCam and MIRI,
respectively.
Description:
The evolutionary calculations presented here were obtained with the
evolutionary model described in Jin et al. (2014ApJ...795...65J 2014ApJ...795...65J),
which is itself based on the model of planetary evolution of Mordasini
et al. (2012A&A...547A.111M 2012A&A...547A.111M,2012A&A...547A.112M 2012A&A...547A.112M). This model describes
the planets as consisting of three distinct homogeneous layers, namely
a H/He envelope (using the equation of state (EoS) of Saumon et al.
1995ApJS...99..713S 1995ApJS...99..713S), an ice layer (for planets which have accreted
outside of the iceline), and a rocky core, which itself consists of
silicates and iron. To address the cooling and contraction of very
low-mass planets, we have extended the model in regard to two aspects.
COOLING CURVES:
The filename:
The first number corresponds to the atmospheric model, -2 is for the
petitCODE grid, -3 for the HELIOS grid.
Then the metallicity is given.
There are different models, clear and with clouds. If the model
contains clouds, the settling parameter fsed is given.
The planetary mass in Earth masses is at the end of the filename.
For some masses, also brighter and fainter cases are calculated. These
are named with a _brighter resp. _fainter in the end.
The header:
The header repeats the file name information, it gives a conversion
factor for the luminosity and the column names and units. All the
magnitudes are in absolute magnitudes.
In the files:
The planetary characteristics and magnitudes are given as long as the
magnitudes can be calculated, which means as long as the planet is
evolving in the logg-temperature of the atmospheric grid. For the
cloudy grid, the magnitudes are calculated as long as the planet is
above 200K.
ISOCHRONES:
The filename:
Khe first number corresponds to the atmosphric model, -2 is for the
petitCODE grid, -3 for the HELIOS grid.
Then the metallicity is given.
There are different models, clear and with clouds. If the model
contains clouds, the settling parameter fsed is given.
For some masses, also brighter and fainter cases are calculated. These
are named with a _brighter resp. _fainter in the end.
The header: The header repeats the file name information, it gives a
conversion factor for the luminosity and the column names and units.
All the magnitudes are in absolute magnitudes.
In the files:
The planetary characteristics and magnitudes are given as long as the
magnitudes can be calculated, which means as long as the planet is
evolving in the logg-temperature of the atmospheric grid. For the
cloudy grid, the magnitudes are calculated as long as the planet is
above 200K.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
listcool.dat 64 90 List of files in cooling_curves subdirectory
listiso.dat 53 13 List of files in isochrones subdirectory
vegasp.dat 24 8839 Vega spectrum (alphalyrstis003eng.txt)
cooling_curves/* . 90 Individual cooling curves
isochrones/* . 13 Individual isochrones
--------------------------------------------------------------------------------
Byte-by-byte Description of file: listcool.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Model [-3/-2] atmospheric model
(-2 = petitCODE grid, -3 = HELIOS grid)
4- 7 F4.1 --- [Fe/H] Metallicity
9- 12 F4.2 --- fsed [1]? settling parameter fsed
if the model contains clouds
14- 16 I3 Mgeo Mass [5/636] Planet mass
18 A1 ---- Note [bf] b for brighter, f for fainter
20- 64 A45 --- FileName Name of the file in subdirectory cooling_curves
--------------------------------------------------------------------------------
Byte-by-byte Description of file: listiso.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Model [-3/-2] atmospheric model
(-2 = petitCODE grid, -3 = HELIOS grid)
4- 7 F4.1 --- [Fe/H] Metallicity
9- 12 F4.2 --- fsed [1]? settling parameter fsed
if the model contains clouds
14 A1 ---- Note [bf] b for brighter, f for fainter
16- 53 A38 --- FileName Name of the file in subdirectory isochrones
--------------------------------------------------------------------------------
Byte-by-byte Description of file: vegasp.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.6 um lambda Wavelength
13- 24 E12.7 --- Flux Flux
--------------------------------------------------------------------------------
Byte-by-byte Description of file (#): cooling_curves/* isochrones/*
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
9- 12 F4.1 [yr] logAge Age
20- 24 F5.1 Mgeo Mass Mass, Earth mass units
32- 36 F5.3 Jup Rad Radius (in Jupiter radius)
40- 48 F9.3 Jup Lum Luminosity (in Jupiter luminosity)
54- 60 F7.3 K Teff Effective temperature
68- 72 F5.3 [cm/s2] logg Surface gravity
80- 84 F5.2 mag JMAGNACO Absolute NACO J magnitude
92- 96 F5.2 mag HMAGNACO Absolute NACO H magnitude
104-108 F5.2 mag KsMAGNACO Absolute NACO Ks magnitude
116-120 F5.2 mag LpMAGNACO Absolute NACO Lp magnitude
128-132 F5.2 mag MpMAGNACO Absolute NACO Mp magnitude
140-144 F5.2 mag RcMAG Absolute Cousins R magnitude
152-156 F5.2 mag IcMAG Absolute Cousins I magnitude
164-168 F5.2 mag W1MAG Absolute WISE1 magnitude
176-180 F5.2 mag W2MAG Absolute WISE2 magnitude
188-192 F5.2 mag W3MAG Absolute WISE3 magnitude
200-204 F5.2 mag W4MAG Absolute WISE4 magnitude
212-216 F5.2 mag F115WMAG Absolute F115W magnitude
224-228 F5.2 mag F150WMAG Absolute F150W magnitude
236-240 F5.2 mag F200WMAG Absolute F200W magnitude
248-252 F5.2 mag F277WMAG Absolute F277W magnitude
260-264 F5.2 mag F356WMAG Absolute F356W magnitude
272-276 F5.2 mag F444WMAG Absolute F444W magnitude
284-288 F5.2 mag F560WMAG Absolute F560W magnitude
296-300 F5.2 mag F770WMAG Absolute F770W magnitude
308-312 F5.2 mag F1000WMAG Absolute F1000W magnitude
320-324 F5.2 mag F1280WMAG Absolute F1280W magnitude
332-336 F5.2 mag F1500WMAG Absolute F1500W magnitude
344-348 F5.2 mag F1800WMAG Absolute F1800W magnitude
356-360 F5.2 mag F2100WMAG Absolute F2100W magnitude
368-372 F5.2 mag F2550Wmag Absolute F2550W magnitude
380-384 F5.2 mag B87MAGVIS Absolute VISIRB87 magnitude
392-396 F5.2 mag SiCMAGVIS Absolute VISIRSiC magnitude
404-408 F5.2 mag YMAGS Absolute SPHEREY magnitude
416-420 F5.2 mag JMAGS Absolute SPHEREJ magnitude
428-432 F5.2 mag HMAGS Absolute SPHEREH magnitude
440-444 F5.2 mag KsMAGS Absolute SPHEREKs magnitude
452-456 F5.2 mag J2MAGS Absolute SPHEREJ2 magnitude
464-468 F5.2 mag J3MAGS Absolute SPHEREJ3 magnitude
476-480 F5.2 mag H2MAGS Absolute SPHEREH2 magnitude
488-492 F5.2 mag H3MAGS Absolute SPHEREH3 magnitude
500-504 F5.2 mag K1MAGS Absolute SPHEREK1 magnitude
512-516 F5.2 mag K2MAGS Absolute SPHEREK2 magnitude
--------------------------------------------------------------------------------
History:
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(End) Patricia Vannier [CDS] 06-Mar-2019