Spatially dense Airborne Electromagnetic Method (AEM) surveys are increasingly acquired to provide a background for creating 3D geological models. These datasets provide a high degree of detail that ...is very time-consuming and challenging to incorporate in manually-produced geological models. Automated modelling methods are therefore needed to make the modelling process more time-efficient. In this study we evaluate the results of two automated modelling methods against the results of a manually constructed geological model. The study area is characterized by a sequence of Quaternary glacial till deposits on top of Pre-Quaternary sand and clay deposits. The tested automatic methods are 1) an approach for clay fraction modelling, where borehole and AEM resistivity models are integrated through inversion, and 2) a stochastic approach based on transition probability indicator statistics. The most significant difference between the model results is the ability of the manually constructed geological model to contain stratigraphic information, contrary to the sand–clay models generated by the automated approaches. When all the model results are translated to binary models, they are generally in good agreement. The models have different strengths and limitations and the later application of the model should therefore be taken into consideration when choosing the modelling approach.
•Geological modelling of AEM and borehole data•Translation of resistivities to lithology•Comparing modelling results•Modelling method should be chosen to fit the application.
During the High Modernism period spanning from approximately 1914 to 1970, the manufacturing of steel-constructed system halls witnessed a significant surge to accommodate the growing demand across ...various sectors such as industry, commerce, and agriculture. Surprisingly, these specific types of buildings have been largely overlooked in the realm of construction history research, resulting in a dearth of knowledge regarding their construction methods, distribution patterns, and contextual significance for assessing their historical value. This study aims to address this gap by exploring the potential of instance segmentation methods for the automated detection of system halls using high-resolution aerial imagery. To achieve this objective, state-of-the-art deep learning models are evaluated in terms of their ability to localize and delineate system halls accurately. Our experiments reveal that Mask R-CNN yields the most accurate results both quantitatively and qualitatively, closely followed by Cascade Mask R-CNN. However, it is important to note that multi-scale methods may introduce false positives since system halls possess distinct geometric dimensions that necessitate careful consideration during the detection process.
Aims
. We report the discovery and characterisation of the transiting mini-Neptune HD 207496 b (TOI-1099) as part of a large programme that aims to characterise naked core planets.
Methods
. We ...obtained HARPS spectroscopic observations, one ground-based transit, and high-resolution imaging which we combined with the TESS photometry to confirm and characterise the TESS candidate and its host star.
Results
. The host star is an active early K dwarf with a mass of 0.80 ± 0.04
M
⊙
, a radius of 0.769 ± 0.026
R
⊙
, and a
G
magnitude of 8. We found that the host star is young, ~0.52 Gyr, allowing us to gain insight into planetary evolution. We derived a planetary mass of 6.1 ± 1.6
M
⊕
, a planetary radius of 2.25 ± 0.12
R
⊕
, and a planetary density of
ρ
p
= 3.27
−0.91
+0.97
g cm
−3
.
Conclusions
. From internal structure modelling of the planet, we conclude that the planet has either a water-rich envelope, a gas-rich envelope, or a mixture of both. We have performed evaporation modelling of the planet. If we assume the planet has a gas-rich envelope, we find that the planet has lost a significant fraction of its envelope and its radius has shrunk. Furthermore, we estimate it will lose all its remaining gaseous envelope in ~0.52 Gyr. Otherwise, the planet could have already lost all its primordial gas and is now a bare ocean planet. Further observations of its possible atmosphere and/or mass-loss rate would allow us to distinguish between these two hypotheses. Such observations would determine if the planet remains above the radius gap or if it will shrink and be below the gap.
Context.
Most of the currently known planets are small worlds with radii between that of the Earth and that of Neptune. The characterization of planets in this regime shows a large diversity in ...compositions and system architectures, with distributions hinting at a multitude of formation and evolution scenarios. However, many planetary populations, such as high-density planets, are significantly under-sampled, limiting our understanding of planet formation and evolution.
Aims.
NCORES is a large observing program conducted on the HARPS high-resolution spectrograph that aims to confirm the planetary status and to measure the masses of small transiting planetary candidates detected by transit photometry surveys in order to constrain their internal composition.
Methods.
Using photometry from the K2 satellite and radial velocities measured with the HARPS and CORALIE spectrographs, we searched for planets around the bright (
V
mag
= 10) and slightly evolved Sun-like star HD 137496.
Results.
We precisely estimated the stellar parameters,
M
*
= 1.035 ± 0.022
M
⊙
,
R
*
= 1.587 ± 0.028
R
⊙
,
T
eff
= 5799 ± 61 K, together with the chemical composition (e.g. Fe/H = −0.027 ± 0.040 dex) of the slightly evolved star. We detect two planets orbiting HD 137496. The inner planet, HD 137496 b, is a super-Mercury (an Earth-sized planet with the density of Mercury) with a mass of
M
b
= 4.04 ± 0.55
M
⊕
, a radius of R
b
= 1.31
−0.05
+0.06
R
⊕
, and a density of ρ
b
= 10.49
−1.82
+2.08
g cm
-3
. With an interior modeling analysis, we find that the planet is composed mainly of iron, with the core representing over 70% of the planet’s mass (M
core
/ M
total
= 0.73
−0.12
+0.11
). The outer planet, HD 137496 c, is an eccentric (
e
= 0.477 ± 0.004), long period (
P
= 479.9
−1.1
+1.0
days) giant planet (
M
c
sin
i
c
= 7.66 ± 0.11
M
Jup
) for which we do not detect a transit.
Conclusions.
HD 137496 b is one of the few super-Mercuries detected to date. The accurate characterization reported here enhances its role as a key target to better understand the formation and evolution of planetary systems. The detection of an eccentric long period giant companion also reinforces the link between the presence of small transiting inner planets and long period gas giants.
Multicolour broad-band transit observations offer the opportunity to characterize the atmosphere of an extrasolar planet with small- to medium-sized telescopes. One of the most favourable targets is ...the hot Jupiter HAT-P-32 b. We combined 21 new transit observations of this planet with 36 previously published light curves for a homogeneous analysis of the broad-band transmission spectrum from the Sloan u′ band to the Sloan z′ band. Our results rule out cloud-free planetary atmosphere models of solar metallicity. Furthermore, a discrepancy at reddest wavelengths to previously published results makes a recent tentative detection of a scattering feature less likely. Instead, the available spectral measurements of HAT-P-32 b favour a completely flat spectrum from the near-UV to the near-IR. A plausible interpretation is a thick cloud cover at high altitudes.
We report the characterization of two planet candidates detected by the Transiting Exoplanet Survey Satellite (TESS), TOI-1199 b and TOI-1273 b, with periods of 3.7 and 4.6 days, respectively. ...Follow-up observations for both targets, which include several ground-based light curves, confirmed the transit events. High-precision radial velocities from the SOPHIE spectrograph revealed signals at the expected frequencies and phases of the transiting candidates and allowed mass determinations with a precision of 8.4% and 6.7% for TOI-1199 b and TOI-1273 b, respectively. The planetary and orbital parameters were derived from a joint analysis of the radial velocities and photometric data. We find that the planets have masses of 0.239 ± 0.020 M J and 0.222 ± 0.015 M J and radii of 0.938 ± 0.025 R J and 0.99 ± 0.22 R J , respectively. The grazing transit of TOI-1273 b translates to a larger uncertainty in its radius, and hence also in its bulk density, compared to TOI-1199 b. The inferred bulk densities of 0.358 ± 0.041 g cm −3 and 0.28 ± 0.11 g cm −3 are among the lowest known for exoplanets in this mass range, which, considering the brightness of the host stars ( V ≈11 mag), render them particularly amenable to atmospheric characterization via the transit spectroscopy technique. The better constraints on the parameters of TOI-1199 b provide a transmission spectroscopy metric of 134 ± 17, making it the better suited of the two planets for atmospheric studies.
ABSTRACT
High precision time-series photometry from space is being used for a number of scientific cases. In this context, the recently launched CHaracterizing ExOPlanet Satellite (CHEOPS) (ESA) ...mission promises to bring 20 ppm precision over an exposure time of 6 h, when targeting nearby bright stars, having in mind the detailed characterization of exoplanetary systems through transit measurements. However, the official CHEOPS (ESA) mission pipeline only provides photometry for the main target (the central star in the field). In order to explore the potential of CHEOPS photometry for all stars in the field, in this paper, we present archi, an additional open-source pipeline module1 to analyse the background stars present in the image. As archi uses the official data reduction pipeline data as input, it is not meant to be used as an independent tool to process raw CHEOPS data but, instead, to be used as an add-on to the official pipeline. We test archi using CHEOPS simulated images, and show that photometry of background stars in CHEOPS images is only slightly degraded (by a factor of 2–3) with respect to the main target. This opens a potential for the use of CHEOPS to produce photometric time-series of several close-by targets at once, as well as to use different stars in the image to calibrate systematic errors. We also show one clear scientific application where the study of the companion light curve can be important for the understanding of the contamination on the main target.
We present the discovery of two new transiting extrasolar planet candidates identified as TOI-1296.01 and TOI-1298.01 by the Transiting Exoplanet Survey Satellite (TESS). The planetary nature of ...these candidates has been secured with the SOPHIE high-precision spectrograph through the measurement of the companion’s mass with the radial velocity method. Both planets are similar to Saturn in mass and have similar orbital periods of a few days. They, however, show discrepant radii and therefore different densities. The radius discrepancy might be explained by the different levels of irradiation by the host stars. The subgiant star TOI-1296 hosts a low-density planet with 1.2
R
Jup
while the less luminous, lower-size star TOI-1298 hosts a much denser planet with a 0.84
R
Jup
radius, resulting in bulk densities of 0.198 and 0.743 g cm
−3
, respectively.In addition, both stars are strongly enriched in heavy elements, having metallicities of +0.44 and +0.49 dex, respectively. The planet masses and orbital periods are 0.298 ± 0.039
M
Jup
and 3.9443715 ± 5.8 ± 10
−6
days for TOI-1296b, and 0.356 ± 0.032
M
Jup
and 4.537164 ± 1.2 ± 10
−5
days for TOI-1298b. The mass measurements have a relative precision of better than 13%.
Kepler Object of Interest Network Freudenthal, J.; von Essen, C.; Ofir, A. ...
Astronomy and astrophysics (Berlin),
2019, Letnik:
628
Journal Article
Recenzirano
Odprti dostop
Context.
The
Kepler
Object of Interest Network (KOINet) is a multi-site network of telescopes around the globe organised for follow-up observations of transiting planet candidate
Kepler
objects of ...interest with large transit timing variations (TTVs). The main goal of KOINet is the completion of their TTV curves as the
Kepler
telescope stopped observing the original
Kepler
field in 2013.
Aims.
We ensure a comprehensive characterisation of the investigated systems by analysing
Kepler
data combined with new ground-based transit data using a photodynamical model. This method is applied to the Kepler-82 system leading to its first dynamic analysis.
Methods.
In order to provide a coherent description of all observations simultaneously, we combine the numerical integration of the gravitational dynamics of a system over the time span of observations with a transit light curve model. To explore the model parameter space, this photodynamical model is coupled with a Markov chain Monte Carlo algorithm.
Results.
The Kepler-82b/c system shows sinusoidal TTVs due to their near 2:1 resonance dynamical interaction. An additional chopping effect in the TTVs of Kepler-82c hints to a further planet near the 3:2 or 3:1 resonance. We photodynamically analysed
Kepler
long- and short-cadence data and three new transit observations obtained by KOINet between 2014 and 2018. Our result reveals a non-transiting outer planet with a mass of
m
f
= 20.9 ± 1.0
M
⊕
near the 3:2 resonance to the outermost known planet, Kepler-82c. Furthermore, we determined the densities of planets b and c to the significantly more precise values ρ
b
= 0.98
−0.14
+0.10
g cm
−3
and ρ
c
= 0.494
−0.077
+0.066
g cm
−3
.
The expression of aquaporins (AQPs) in the fetal porcine urinary tract and its relation to gestational age has not been established. Tissue samples from the renal pelvis, ureter, bladder and urethra ...were obtained from porcine fetuses. Samples were examined by RT-PCR (AQPs 1-11), QPCR (AQPs positive on RT-PCR), and immunohistochemistry. Bladder samples were additionally examined by Western blotting. RNA was extracted from 76 tissue samples obtained from 19 fetuses. Gestational age was 60 (n=11) or 100 days (n=8). PCR showed that AQP1, 3, 9 and 11 mRNA was expressed in all locations. The expression of AQP3 increased significantly at all four locations with gestational age, whereas AQP11 significantly decreased. AQP1 expression increased in the ureter, bladder and urethra. AQP9 mRNA expression increased in the urethra and bladder, but decreased in the ureter. AQP5 was expressed only in the urethra. Immunohistochemistry showed AQP1 staining in sub-urothelial vessels at all locations. Western blotting analysis confirmed increased AQP1 protein levels in bladder samples during gestation. Expression levels of AQP1, 3, 5, 9 and 11 in the urinary tract change during gestation, and further studies are needed to provide insights into normal and pathophysiological water handling mechanisms in the fetus.
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