J/MNRAS/498/6013 Strong-lensing systems for dark energy models (Amante+, 2020)
Testing dark energy models with a new sample of strong-lensing systems.
Amante M.H., Magana J., Motta V., Garcia-Aspeitia M.A., Verdugo T.
<Mon. Not. R. Astron. Soc., 498, 6013-6033 (2020)>
=2020MNRAS.498.6013A 2020MNRAS.498.6013A (SIMBAD/NED BibCode)
ADC_Keywords: Gravitational lensing ; Redshifts ; Velocity dispersion ; Optical
Keywords: gravitational lensing: strong - cosmological parameters -
dark energy - cosmology: observations - cosmology: theory
Abstract:
Inspired by a new compilation of strong-lensing systems, which consist
of 204 points in the redshift range 0.0625<zl<0.958 for the lens and
0.196<zs<3.595 for the source, we constrain three models that
generate a late cosmic acceleration: the ω-cold dark matter
model, the Chevallier-Polarski-Linder, and the
Jassal-Bagla-Padmanabhan parametrizations. Our compilation contains
only those systems with early-type galaxies acting as lenses, with
spectroscopically measured stellar velocity dispersions, estimated
Einstein radius, and both the lens and source redshifts. We assume an
axially symmetric mass distribution in the lens equation, using a
correction to alleviate differences between the measured velocity
dispersion (σ) and the dark matter halo velocity dispersion
(σDM) as well as other systematic errors that may affect the
measurements. We have considered different subsamples to constrain the
cosmological parameters of each model. Additionally, we generate a
mock data of SLS to asses the impact of the chosen mass profile on the
accuracy of Einstein radius estimation. Our results show that
cosmological constraints are very sensitive to the selected data: Some
cases show convergence problems in the estimation of cosmological
parameters (e.g. systems with observed distance ratio Dobs<0.5),
others show high values for the χ2 function (e.g. systems with a
lens equation Dobs>1 or high velocity dispersion σ>276km/s).
However, we obtained a fiduciary sample with 143 systems, which
improves the constraints on each tested cosmological model.
Description:
To construct Dobs, we have chosen only systems with
spectroscopically data well measured from different surveys. We have
considered 19 strong-lensing systems (SLS) from the CASTLES, 107 from
SLACS, 38 from BELLS, 4 from LSD, 35 from SL2S, and 1 system from the
DES survey. The final list has a total of 204 systems, being the
largest sample of SLS to date. We use spectroscopy to select those
lenses with lenticular (S0) or elliptical (E) morphologies that have
been modelled assuming a singular isothermal sphere (SIS) (∼3 per
cent) or singular isothermal ellipsoid (SIE) (∼97 per cent) lens
model. Many systems have not been taken into account due to several
issues.
Our final sample is presented in Table A1, having a total of 204 data
points whose lens and source redshifts are in the ranges
0.0625<zl<0.958 and 0.196<zs<3.595, respectively. All the systems
for which we assumed a velocity dispersion error are marked in the
sample.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablea1.dat 149 204 Compilation of 204 strong-lensing measurements
tablea2.dat 49 32 Thirty two gravitational lens systems with
Dobs>1
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 23 A23 --- Name System name
25- 31 A7 --- Survey Survey name
33- 38 F6.4 --- zl Lens redshift
40- 45 F6.4 --- zs Source redshift
47- 51 F5.3 arcsec thetaE Einstein radius θE
53- 56 F4.2 arcsec e_thetaE ? Error on thetaE
58- 60 I3 km/s sigma Velocity dispersion σ
62- 64 I3 km/s E_sigma Upper error on sigma
66- 67 I2 km/s e_sigma Lower error on sigma
69 A1 --- f_sigma [a] Flag on sigma (1)
71- 149 A79 --- Ref References
--------------------------------------------------------------------------------
Note (1): Flag as follows:
a = For this source the uncertainties were estimated
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 23 A23 --- Name System name
25- 42 F18.16 --- Dobs Observed distance ratio Dobs (1)
44- 47 F4.2 arcsec thetaE Einstein radius θE
49 A1 --- Flag [*] Flag (2)
--------------------------------------------------------------------------------
Note (1): Dobs can be computed as: Dobs=c2θE/(4πσ2),
where σ is the measured velocity dispersion of the lens DM halo
Note (2): Flag as follows:
* = This object is not a confirmed lens, or has complex source structures
with multiple arcs and counter-arcs, or the foreground lens is clearly
composed of two distinct components, has uncertain redshift
measurements, or the arcs (rings) are embedded in the light of the
foreground lens
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 14-Aug-2023