Extreme exoplanets as a tool to understand trends in exoplanets atmospheres.

2021 ◽  
Author(s):  
Bob Jacobs ◽  
Jean-Michel Désert ◽  
Saugata Barat ◽  
Michael Line ◽  
Lorenzo Pino
Keyword(s):  
Data Analysis ◽  
Hubble Space Telescope ◽  
Extreme Conditions ◽  
Wide Field ◽  
Atmospheric Physics ◽  
Atmospheric Processes ◽  
Analysis Techniques ◽  
Hot Jupiters ◽  
Wide Range ◽  
Composition Structure

<div>The interpretation of general trends in exoplanet atmospheres is challenging because they exhibit a wide range of diverse properties in terms of composition, structure, and overall atmospheric physics. In this context exoplanet’s in extreme regimes can help to understand global planetary properties.</div> <div><strong> </strong></div> <div>In this project, we focus on a few exoplanets that are outliers in their atmospheric properties and discuss what we can learn about the overall population of hot-jupiters from these peculiar objects.  We present studies of exo-atmospheric processes in extreme regimes of temperature, of entropy, of radiative and advective timescales, and of formation stages. This project combines these various physical properties in a unique and innovative manner to understand the most crucial properties of hot-Jupiters.</div> <div><strong> </strong></div> <p>Practically, we leverage the unique capabilities of Hubble Space Telescope Wide Field Camera 3 together with novel data analysis techniques to understand the nature of a set of exoplanets that reside under these extreme conditions. Ultimately, this project enable us to improve our understanding of exo-atmospheric processes and planet formation that ultimately shape the atmospheres of hot Jupiters that are observed today. </p>

scholarly journals The Emission Spectrum of the Hot Jupiter WASP-79b from HST/WFC3

2021 ◽  
Vol 163 (1) ◽  
pp. 7
Author(s):  
Trevor O. Foote ◽  
Nikole K. Lewis ◽  
Brian M. Kilpatrick ◽  
Jayesh M. Goyal ◽  
Giovanni Bruno ◽  
...  
Keyword(s):  
Emission Spectrum ◽  
Energy Transport ◽  
Thermal Emission ◽  
Hubble Space Telescope ◽  
Vertical Mixing ◽  
Wide Field ◽  
Forward Models ◽  
Wide Range ◽  
Solar Metallicity ◽  
Recirculation Factor

Abstract Here we present a thermal emission spectrum of WASP-79b, obtained via Hubble Space Telescope Wide Field Camera 3 G141 observations as part of the PanCET program. As we did not observe the ingress or egress of WASP-79b’s secondary eclipse, we consider two scenarios: a fixed mid-eclipse time based on the expected occurrence time, and a mid-eclipse time as a free parameter. In both scenarios, we can measure thermal emission from WASP-79b from 1.1 to 1.7 μm at 2.4σ confidence consistent with a 1900 K brightness temperature for the planet. We combine our observations with Spitzer dayside photometry (3.6 and 4.5 μm) and compare these observations to a grid of atmospheric forward models that span a range of metallicities, carbon-to-oxygen ratios, and recirculation factors. Given the strength of the planetary emission and the precision of our measurements, we found a wide range of forward models to be consistent with our data. The best-match equilibrium model suggests that WASP-79b’s dayside has a solar metallicity and carbon-to-oxygen ratio, alongside a recirculation factor of 0.75. Models including significant H− opacity provide the best match to WASP-79b’s emission spectrum near 1.58 μm. However, models featuring high-temperature cloud species—formed via vigorous vertical mixing and low sedimentation efficiencies—with little day-to-night energy transport also match WASP-79b’s emission spectrum. Given the broad range of equilibrium chemistry, disequilibrium chemistry, and cloudy atmospheric models consistent with our observations of WASP-79b’s dayside emission, further observations will be necessary to constrain WASP-79b’s dayside atmospheric properties.

Troubleshooting Gas Compression Systems Using Data Analysis

2021 ◽  
Author(s):  
Abdullah Al-Aiderous
Keyword(s):  
Data Analysis ◽  
Field Trial ◽  
Operating Cost ◽  
International Standards ◽  
Mechanical Seal ◽  
Process Data ◽  
Compression System ◽  
Analysis Techniques ◽  
Gas Compression ◽  
Wide Range

Abstract The objective of this paper is to showcase the successful and innovative troubleshooting data analysis techniques in one of the gas compression systems in upstream gas oil separation plants (GOSP-A). The gas compression system using gas compressors, dry gas seal systems and due point controls is used in almost all of upstream operation. These proven data analysis techniques were used to tackle major and chronic issues associated with gas compression system operation that lead to excessive flaring, mechanical seal failures, solidification, hydrate formation and off-specification products. Dry Gas mechanical seals are an important key element in gas compression and its lifetime represents a concern to the operation personnel. Most gas compression systems have a mechanical seal lifetime of 2 years which in some cases limit production, increase the potential of unnecessary flaring and increase OPEX significantly. In addition, solidification due to constant liquid carry over result in a wide range of undesirable results such as blockages that constrain production rates and result in safety concerns. In this paper, comprehensive data analysis of the potential root causes that aggravate undesired premature mechanical seal failure, material solidification, equipment damage and off-specification gas products will be discussed along with solutions to minimize expected impact. For example, improper product specification in some applications have been found to promote seal failures, corrosion, solidification and incur additional flaring which is both costly and environmentally undesirable. In addition, after extensive analysis improper operation practices during compressor startups, steady state operation and gas conditioning have been linked with premature compressor failures, product off spec and safety device failures. The field trial proved the effectiveness of the proposed innovative troubleshooting data analysis techniques in reinstating the gas compression unit in GOSP-A to its recommended design conditions, eliminated compressors and mechanical seal failures and avoided the off-specification products at the lowest operating cost. This innovative technique was based on deep and extensive process data analysis, evaluating operating and design data, reviewing international standards, benchmarking against other facilities, process simulation using Hysys, and finally the actual field trial.

Characterising Two Ultra-Hot Jupiters with the Hubble Space Telescope

2020 ◽  
Author(s):  
Billy Edwards ◽  
Quentin Changeat ◽  
William Pluriel ◽  
Niall Whiteford ◽  
Kai Hou Yip ◽  
...  
Keyword(s):  
Emission Spectrum ◽  
Hubble Space Telescope ◽  
Cloud Model ◽  
Thermal Structure ◽  
Emission Spectra ◽  
Pressure Profile ◽  
Wide Field ◽  
Space Telescope ◽  
Thermal Inversion ◽  
Hot Jupiters

<p>The Hubble Space Telescope’s Wide Field Camera 3 (WFC3) has been widely used for transmission and emission spectroscopy of exoplanet atmospheres, identifying the main molecular constituents, detecting the presence of clouds and probing their thermal structure. Hubble observations of the emission spectra of a number of ultra-hot Jupiters have led to somewhat surprising results. Initially, these very hot planets were predicted to have inverted temperature pressure profiles due to strong optical absorption by TiO/VO in the upper atmospheres. However, observations of their emission spectra have been inconclusive on their thermal structure and composition. While some datasets show rich spectral features, others can be fit with simple blackbody models.</p> <p>We will present the analysis of Hubble WFC3 transmission and emission spectra for two ultra-hot Jupiters: WASP-76 b and KELT-7 b. In each case, the data was reduced and fitted using the open-source codes Iraclis and Taurex3. Previous studies of the WFC3 transmission spectra of WASP-76 b found hints of TiO and VO or non-grey clouds. Accounting for a fainter stellar companion to WASP-76, we reanalyse this data and show that removing the effects of this background star changes the slope of the spectrum, resulting in these visible absorbers no longer being detected, removing the need for a non-grey cloud model to adequately fit the data but maintaining the strong water feature previously seen. However, our analysis of the emission spectrum suggests the presence of titanium oxide (TiO) and an atmospheric thermal inversion. Meanwhile, our study of KELT-7 b uncovers a rich transmission spectrum which suggests the presence of water and H-. In contrast, the extracted emission spectrum does not contain strong absorption features and, although it is not consistent with a simple blackbody, it can be explained by a varying temperature-pressure profile, collision induced absorption (CIA) and H-. </p> <p>These finding bring new insights into the nature of this intriguing class of planets but more data is required to fully understand them and thus we will also present the anticipated results of further characterisation.</p>

scholarly journals Exoplanet Transit Spectroscopy of Hot Jupiters Using HST/WFC3

2013 ◽  
Vol 8 (S299) ◽  
pp. 266-270
Author(s):  
Korey Haynes ◽  
Avi M. Mandell ◽  
Evan Sinukoff ◽  
Nikku Madhusudhan ◽  
Adam Burrows ◽  
...  
Keyword(s):  
Extrasolar Planets ◽  
Hubble Space Telescope ◽  
Atmospheric Composition ◽  
Absorption Feature ◽  
Wide Field ◽  
Molecular Absorption ◽  
Broad Absorption ◽  
Hot Jupiters ◽  
Multi Wavelength ◽  
Low Amplitude

AbstractWe present analysis of transit spectroscopy of three extrasolar planets, WASP-12 b, WASP-17 b, and WASP-19 b, using the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). Measurement of molecular absorption in the atmospheres of these planets offers the chance to explore several outstanding questions regarding the atmospheric structure and composition of these highly irradiated, Jupiter-mass objects. We analyze the data for a single transit for each planet, using a strategy similar in certain aspects to the techniques used by Berta (2012), and achieve almost photon-limited results for individual spectral bins. Our final transit spectra are consistent with the presence of a broad absorption feature at 1.4 μm most likely due to water, but the amplitude of the absorption is less than expected based on previous observations with Spitzer, possibly due to hazes absorbing in the NIR. However, the degeneracy of models with different compositions and temperature structures combined with the low amplitude of any features in the data preclude our ability to place unambiguous constraints on the atmospheric composition without a comprehensive multi-wavelength analysis.

Characterising the Hot Jupiters WASP-127\,b, WASP-79\,b and WASP-62\,b with HST

2020 ◽  
Author(s):  
Nour Skaf
Keyword(s):  
Hubble Space Telescope ◽  
Wide Field ◽  
Space Telescope ◽  
Hot Jupiters ◽  
James Webb Space Telescope ◽  
Cloudy Atmosphere ◽  
Iron Hydride ◽  
Short Period ◽  
And Migration ◽  
Best Fit

<p>We would like to present the atmospheric characterisation of three large, gaseous planets: WASP-127b, WASP-79b and WASP-62b. We analysed spectroscopic data obtained with the G141 grism (1.088 - 1.68 um) of the Wide Field Camera 3 (WFC3) onboard the Hubble Space Telescope (HST) using the Iraclis pipeline and the TauREx3 retrieval code, both of which are publicly available. For WASP-127b, which is the least dense planet discovered so far and is located in the short-period Neptune desert, our retrieval results found strong water absorption corresponding to an abundance of log(H$_2$O) = -2.71$^{+0.78}_{-1.05}$, and absorption compatible with an iron hydride abundance of log(FeH)=$-5.25^{+0.88}_{-1.10}$, with an extended cloudy atmosphere.<br />We also detected water vapour in the atmospheres of WASP-79b and WASP-62b, with best-fit models indicating the presence of iron hydride, too.<br />We used the Atmospheric Detectability Index (ADI) as well as Bayesian log evidence to quantify the strength of the detection and compared our results to the hot Jupiter population study by Tsiaras et al 2018.<br />While all the planets studied here are suitable targets for characterisation with upcoming facilities such as the James Webb Space Telescope (JWST) and Ariel, WASP-127b is of particular interest due to its low density, and a thorough atmospheric study would develop our understanding of planet formation and migration. </p>

PENGARUH PERBAIKAN BERKESINAMBUNGAN TERHADAP KINERJA KARYAWAN (STUDI KASUS DI PT.RENTANG BUANA NIAGAMAKMUR TASIKMALAYA)

2019 ◽  
Vol 3 (1) ◽  
pp. 31-41
Author(s):  
Sri Sudiarti
Keyword(s):  
Data Analysis ◽  
Continuous Improvement ◽  
Research Method ◽  
Employee Performance ◽  
Sampling Technique ◽  
Positive Influence ◽  
Performance Criteria ◽  
Coefficient Of Determination ◽  
Analysis Techniques ◽  
Simple Regression

The objectives of this research are to know and to analyze about the effect of Continuous Improvement on the performance of employees at PT. Rentang Buana Niagamakmur (PT.RBN) Tasikmalaya. Research method which applied in this research is survey research method, while data collecting technique is done by through questionaire. Sampling technique applies sample is accidental sampling technique and the size sample is 55 respondents. Data analysis techniques used in the study is simple regression technique, analysis of the coefficient of determination  and t test. The results showed that the Continuous Improvement  including both criteria, including employee performance criteria, as well as Continuous Improvement  has a positive influence on employee performance of 76,4% in PT . Rentang Buana Niagamakmur (PT.RBN) Tasikmalaya.

INDONESIA LANGUAGE INTERFERENCE FORM IN BASIC PPL LEARNING THAILAND UNHASY COLLEGE SYUDENTS

2020 ◽  
Vol 8 (2) ◽  
pp. 38
Author(s):  
Siti Mariana Ulfa
Keyword(s):  
Qualitative Research ◽  
Data Analysis ◽  
Data Collection ◽  
Teaching Practice ◽  
Data Presentation ◽  
Analysis Techniques ◽  
Thai Students ◽  
The Impact ◽  
Collection Methods ◽  
Recording Techniques

AbstractHumans on earth need social interaction with others. Humans can use more than one language in communication. Thus, the impact that arises when the use of one or more languages is the contact between languages. One obvious form of contact between languages is interference. Interference can occur at all levels of life. As in this study, namely Indonesian Language Interference in Learning PPL Basic Thailand Unhasy Students. This study contains the form of interference that occurs in Thai students who are conducting teaching practices in the classroom. This type of research is descriptive qualitative research that seeks to describe any interference that occurs in the speech of Thai students when teaching practice. Data collection methods in this study are (1) observation techniques, (2) audio-visual recording techniques using CCTV and (3) recording techniques, by recording all data that has been obtained. Whereas the data wetness uses, (1) data triangulation, (2) improvement in perseverance and (3) peer review through discussion. Data analysis techniques in this study are (1) data collection, (2) data reduction, (3) data presentation and (4) conclusions. It can be seen that the interference that occurs includes (1) interference in phonological systems, (2) interference in morphological systems and (3) interference in syntactic systems. 

PENGARUH KEPEMIMPINAN DAN MOTVASI KERJA TERHADAP KUALITAS PELAYANAN PUBLIK (STUDI KASUS PADA KANTOR KEMENTERIAN AGAMA SUNGAI PENUH )

2020 ◽  
Author(s):  
Pahrizal
Keyword(s):  
Data Analysis ◽  
Service Quality ◽  
Public Service ◽  
Random Sampling ◽  
Secondary Data ◽  
Sampling Technique ◽  
Simple Random Sampling ◽  
Primary Data ◽  
Analysis Techniques ◽  
Intervening Variables

The research is proposed to test the influence of Leadership and Motivation Work on Public Service Quality. The population in this study was the Kantor Kementerian Agama Sungai Penuh who had received the last 1 year service at the Kantor Kementerian Agama Sungai Penuh, amounting to 260 people. Furthermore, by using the Slovin formula, a sample size of 158 people was chosen with a sampling technique based on Simple Random Sampling. This study uses primary data and secondary data. Data analysis techniques used are path analysis and hypothesis testing using t test with data analysis using SPSS version 20. The results of the study based on showing that partially the Leadership and motivation work have a positive and significant effect on Public Service Quality. The results also show that motivation work variables act as intervening variables between Leadership and Public Service Quality.

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