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We conducted the first light curve study of the binary star EL Tuc within the Binary Systems of South and North (BSN) Project framework. The photometric observations were made using standard multiband BVRI filters at an observatory in Argentina. We presented a new ephemeris for EL Tuc and a linear fit to the O-C diagram, utilizing our extracted times of minima and additional literature. We employed the PHysics Of Eclipsing BinariEs (PHOEBE) Python code and the Markov chain Monte Carlo (MCMC) approach for the system's light curve analysis. The target system's light curve solution required a cold starspot on the hotter component. We conclude that EL Tuc is a total contact binary system with a low mass ratio of q=0.172+_0.002, an orbital inclination of i=83.74+_0.40 degree, and a fillout factor of f=53.7+_1.6%. We used the P-a relationship and the Gaia Data Release 3 (DR3) parallax method to determine the absolute parameters of EL Tuc to compare the precision of our results. This system was classified as W-type based on the mass and effective temperature of the companion stars. The positions of the systems were depicted on the M-L, M-R, T-M, and q-L_ratio diagrams. The relationship between the spectroscopic and photometric mass ratios of binaries was discussed., Comment: Accepted by the Research in Astronomy and Astrophysics Journal

Reanalyzing contact binaries with space-based photometric data and investigating possible parameter changes can yield accurate samples for theoretical studies. We investigated light curve solutions and fundamental parameters for twenty contact binary systems. The most recent Transiting Exoplanet Survey Satellite (TESS) data is used to analyze. The target systems in the investigation have an orbital period of less than 0.58 days. Light curve solutions were performed using the PHysics Of Eclipsing BinariEs (PHOEBE) Python code version 2.4.9. The results show that systems had various mass ratios from q=0.149 to q=3.915, fillout factors from f=0.072 to f=0.566, and inclinations from i=52.8deg to i=87.3deg. The effective temperature of the stars was less than 7016 K, which was expected given the features of most contact binary stars. Twelve of the target systems' light curves were asymmetrical in the maxima, showing the O'Connell effect, and a starspot was required for light curve solutions. The estimation of the absolute parameters of the binary systems was presented using the a-P empirical relationship and discussed. The orbital angular momentum (J_0) of the systems was calculated. The positions of the systems were also depicted on the M-L, M-R, q-L_ratio, M_tot-J_0, and T-M diagrams., Comment: Accepted by the Astrophysics Journal

This study presented the first light curve analysis of the OP Boo and V0511 Cam binary stars, which was conducted in the frame of the Binary Systems of South and North (BSN) Project. Photometric ground-based observations were conducted with standard filters at two observatories in the Czech Republic. We computed a new ephemeris for each of the systems using our extracted times of minima, TESS data, and additional literature. Linear fits for O-C diagrams of both systems were considered using the Markov Chain Monte Carlo (MCMC) method. The light curves were analyzed using the Wilson-Devinney (WD) binary code combined with the Monte Carlo (MC) simulation. The light curve solutions of both target systems required a cold starspot. The absolute parameters of the systems were calculated by using a P-M parameter relationship. The positions of the systems were also depicted on the Hertzsprung-Russell (HR), P-L, logMtot-logJ0, and T-M diagrams. The second component in both systems is determined to be a more massive and hotter star. Therefore, it can be concluded that both systems are W-type contact binary systems., Comment: 5 Tables, 4 Figures, Astrophysics Journal

The first photometric light curve investigation of the NSVS 8294044, V1023 Her, and V1397 Her binary systems is presented. We used ground-based observations for the NSVS 8294044 system and Transiting Exoplanet Survey Satellite (TESS) data for V1023 Her and V1397 Her. The primary and secondary times of minima were extracted from all the data, and by collecting the literature, a new ephemeris was computed for each system. Linear fits for the O-C diagrams were conducted using the Markov chain Monte Carlo (MCMC) method. Light curve solutions were performed using the PHysics Of Eclipsing BinariEs (PHOEBE) Python code and the MCMC approach. The systems were found to be contact binary stars based on the fillout factor and mass ratio. V1023 Her showed the O'Connell effect, and a cold starspot on the secondary component was required for the light curve solution. The absolute parameters of the system were estimated based on an empirical relationship between orbital period and mass. We presented a new T-M equation based on a sample of 428 contact binary systems and found that our three target systems were in good agreement with the fit. The positions of the systems were also depicted on the M-L, M-R, q-L_{ratio}, and M_{tot}-J_0 diagrams in the logarithmic scales., Comment: Accepted by the Research in Astronomy and Astrophysics Journal

The accuracy of absolute parameters' estimation in contact binary systems is important for investigating their evolution and solving some challenges. The Gaia DR3 parallax is one of the methods used for estimating the absolute parameters, in cases where photometric data is the only one that is available. The use of this method includes advantages and limitations that we have described and examined in this study. We selected 48 contact binary systems whose mass ratios were mostly obtained by spectroscopic data, in addition to a number of photometric studies. The target systems were suitable for A_V and the Re-normalised Unit Weight Error (RUWE), and their absolute parameters were calculated based on Gaia DR3 parallax, observational information, orbital period, and light cure solution from the literature and catalogs. The outcomes of OO Aql differed significantly from those reported in the literature. Upon analyzing the system's light curve with TESS data, we concluded that the stars' temperatures were the reason for this difference, and utilizing Gaia DR3 parallax provided reasonable results. We displayed the target systems on the Hertzsprung-Russell (HR), q-L_ratio, P-M_V, and logM_tot-logJ_0 diagrams, and the systems are in good agreement with the theoretical fits. We showed that the estimation of absolute parameters with this method might be acceptable if Delta a(R_Sun) is less than about 0.1(R_Sun). There are open questions regarding the existence of l_3 in the light curve analysis and its effect on the estimation of absolute parameters with this method., Comment: Accepted by the New Astronomy Journal

The light curve analyses and orbital period variations for two contact binary stars, LS Del and V997 Cyg, were presented in this work which was conducted in the frame of the Binary Systems of South and North (BSN) Project. Ground-based photometric observations were performed at two observatories in France. We used the TESS (Transiting Exoplanet Survey Satellite) data for extracting times of minima and light curve analysis of the target systems. The O-C diagram for both systems displays a parabolic trend. LS Del and V997 Cyg's orbital periods are increasing at a rate of dP/dt= 7.20*10^{-08} d yr^{-1} and dP/dt= 2.54*10^{-08} d yr^{-1}, respectively. Therefore, it can be concluded that the mass is being transferred from the less massive star to the more massive component with a rate of dM/dt= -1.96*10^{-7} M_Sun yr^{-1} for the LS Del system, and dM/dt= -3.83*10^{-7} M_Sun yr^{-1} for V997 Cyg. The parameters of the third possible object in the system were also considered. The PHysics Of Eclipsing BinariEs (PHOEBE) Python code was used to analyze the light curves. The light curve solutions needed a cold starspot due to the asymmetry in the LS Del system's light curve maxima. The mass ratio, fill-out factor, and star temperature all indicate that both systems are contact binary types in this investigation. Two methods were used to estimate the absolute parameters of the systems: one method used the parallax of Gaia DR3, and the other used a P-M relationship. The positions of the systems were also depicted on the M-L, M-R, q-L_{ratio}, and logM_{tot}-logJ_0 diagrams. We recommended that further observations and investigations be done on the existence of the fourth body in this system., Comment: Accepted by the RAA Journal

The Gaia DR3 parallax approach was used to estimate the absolute parameters of 2375 Delta Scuti stars from the ASAS catalog. The selected stars have a variety of observational characteristics, with a higher than 80% probability of being Delta Scuti stars. We have displayed all the stars in the Hertzsprung-Russell (H-R) diagram along with the Delta Scuti instability strip, the Zero Age Main Sequence (ZAMS), and the Terminal-Age Main Sequence (TAMS). Then, we determined which fundamental and overtone modes each star belongs to using pulsation constant (Q) calculations. In addition, we evaluated the parameters in the Q calculation equation using three machine learning methods, which showed that surface gravity and temperature have the greatest effect on its calculation. The Period-Luminosity (P-L) relationship of the Delta Scuti stars was also revisited. Eventually, using least squares linear regression, we made four linear fits for fundamental and overtone modes and updated their relationships., Comment: Accepted by the Research in Astronomy and Astrophysics (RAA) journal

Reviewing the empirical and theoretical parameter relationships between various parameters is a good way to understand more about contact binary systems. In this investigation, two-dimensional (2D) relationships for P-M_V(system), P-L_1,2, M_1,2-L_1,2, and q-L_ratio were revisited. The sample used is related to 118 contact binary systems with an orbital period shorter than 0.6 days whose absolute parameters were estimated based on the Gaia Data Release 3 (DR3) parallax. We reviewed previous studies on 2D relationships and updated six parameter relationships. Therefore, Markov chain Monte Carlo (MCMC) and Machine Learning (ML) methods were used, and the outcomes were compared. We selected 22 contact binary systems from eight previous studies for comparison, which had light curve solutions using spectroscopic data. The results show that the systems are in good agreement with the results of this study., Comment: Accepted by the Research in Astronomy and Astrophysics (RAA) journal

Photometric data were used to perform the first light curve analysis of the V0610 Vir binary system. Observations and analysis were done in the form of the Binary Systems of South and North (BSN) Project. We extracted the minima from our observations and compiled the literature, which was few. Therefore, we performed computations using the reference ephemeris and presented a new ephemeris and O-C diagram with a linear fit. Light curve analysis was performed using the PHOEBE Python code and the Markov chain Monte Carlo (MCMC) approach. The assumption of a hot starspot was required due to the asymmetry in the light curve's maxima. The analysis shows that V0610 Vir is a contact binary system with a fillout factor of 0.085, a mass ratio of 0.998, and an inclination of 70.65-deg. The absolute parameters of the system were estimated based on the Gaia DR3 parallax method. The results show that the system is a low-mass contact binary with a total mass lower than 0.8(M_Sun). The location of the stars was shown in the M-L and M-R diagrams., Comment: Accepted by the Astrophysics Journal

This study presented a new analysis for the TESS-observed W Ursae Majoris (W UMa) binary star YY Coronea Borealis (YY CrB). The light curve was analyzed by the PHysics Of Eclipsing BinariEs (PHOEBE) Python version together with the Markov chain Monte Carlo (MCMC) method. The light curve solutions required a hot spot and l3. New eclipse times from the TESS observations were extracted, and the O-C curve of primary and secondary minima showed an anti-correlated manner. In order to study the O-C curve of minima, minima times between 1991 and 2023 were collected. This investigation reported a new linear ephemeris and by fitting a quadratic function to the O-C curve of minima, calculated the orbital period rate of \mathop P\limits^.\approx 5.786*{10^{-8}} day/year. Assuming mass conservation, a mass exchange rate of \mathop{{M_2}}\limits^.=2.472*{10^{-8}} calculated from the more massive component to the less massive one. Then, by using the light travel time function, the possible third body was determined in the binary and derived the mass of the third body as 0.498M_Sun with a period of \simeq 7351.018 days. The O-C curve analysis and the quantity of mass indicate that the presence of a third body is unlikely. This binary is expected to evolve into a broken-contact phase and is a good case to support the thermal relaxation oscillation model., Comment: Accepted by the New Astronomy Journal

We performed the first photometric study of the CSS J003106.8+313347 W Ursae Majoris (W UMa)-type system based on ground-based observations. We extracted times of minima from our observations and proposed a linear ephemeris based on the increasing incline of the orbital period using a Markov chain Monte Carlo (MCMC) approach. The PHOEBE Python code and the MCMC approach were used for the light curve analysis. This system did not need starspots for the light curve analysis. Mass ratio, fillout factor, and inclination were obtained as 0.699, 0.322, and 60.6deg respectively. We also estimated the absolute parameters of the system using the Gaia DR3 parallax method. Therefore, the masses, radii, and luminosities have been determined to be M1=1.675, M2=1.171, R1=1.292, R2=1.097, L1=1.348, and L2=1.221. The orbital angular momentum (J0) of the CSS J003106.8+313347 illustrates that this system is located in a region of contact binaries. The positions of the primary and secondary components on the Hertzsprung-Russell (HR) diagram are depicted., Comment: Accepted by the Astrophysics journal

The short-period AP Dor eclipsing binary's first in-depth and multiband photometric solutions are presented. We made use of our eight nights of ground-based at a southern hemisphere observatory, and twelve sectors of TESS observations. We extracted eight and 1322 minima from our observations and TESS, respectively. We suggested a new linear ephemeris based on the trend of orbital period variations using the Markov chain Monte Carlo (MCMC) approach. The PHysics Of Eclipsing BinariEs (PHOEBE) Python code and the MCMC approach were used for the light curve analysis. This system did not require a starspot for the light curve solutions. We calculated the absolute parameters of the system using Gaia DR3 parallax method. The orbital angular momentum (J_0) of the AP Dor indicates that this system is located in a region of contact binaries. According to our results, this system is an overcontact binary system with a mass ratio of 0.584, a fillout factor of 48\%, and an inclination of 53deg. The positions of AP Dor stars on the Hertzsprung-Russell (HR) diagram are represented., Comment: Accepted by the Research in Astronomy and Astrophysics (RAA) journal

The first multiband photometric solutions of the short-period V Gru eclipsing binary from the southern hemisphere is presented in this study. Light curves of the system were observed through BVI filters at the Congarinni Observatory in Australia for 15 nights. In addition to the new ground-based data, we also used the TESS observations in two sectors. We analyzed the light curves of the system using the PHysics Of Eclipsing BinariEs (PHOEBE) 2.4.7 version code to achieve the best accordance with the photometric observations. The solutions suggest that V Gru is a near-contact binary system with q=1.302(81) mass ratio, f1=0.010(23), f2=-0.0.009(21), and i=73.45(38). We considered the two hot spots on the hotter and cooler components for the light curve analysis. We extracted the minima times from the light curves based on the Markov Chain Monte Carlo (MCMC) approach. Using our new light curves, TESS, and additional literature minima, we computed the ephemeris of V Gru. The system's eclipse timing variation trend was determined using the MCMC method. This system is a good and challenging case for future studies., Comment: Accepted by the Research in Astronomy and Astrophysics (RAA) journal

We present the photometric analysis of six short-period systems (EI Oct, V336 TrA, NX Boo, V356 Boo, PS Boo, and V2282 Cyg). This is the first photometric analysis of these systems except for V336 TrA. Observations were conducted for 27 nights at three observatories in the northern and southern hemispheres. We calculated a new ephemeris for each of the systems using our minimum times and additional literature. The Markov Chain Monte Carlo (MCMC) approach was used to determine the eclipse timing variation trends of the systems. We found a likely orbital growth for V336 TrA and PS Boo; four other systems show a linear trend in orbital period changes, which is most likely due to the accumulation of measurement errors in their linear ephemeris parameters. The light curve analysis was performed using the Physics of Eclipsing Binaries (PHOEBE) 2.3.59 version code with the MCMC approach. The absolute parameters of the systems were calculated by using the Gaia Early Data Release 3 (EDR3) parallax. The positions of the systems were also depicted on the Hertzsprung-Russell (H-R) and $logJ_0-logM$ diagrams. According to a sample, we were able to present relations for the mass-radius (M-R) relationships of contact binary systems. There is also a strong relationship between the mass ratio and the radius ratio in the W UMa systems for which we also provided a new relation. We compared the M-R updated relationships in this study with seven systems in other studies obtained using the spectroscopic method. In addition, we estimated some of the absolute parameters for 1734 EW systems, based on the new relationships., Comment: 11 Figures, 9 Tables, Accepted by the PASP Journal

The first multi-color light curve analysis of the AH Mic binary system is presented. This system has very few past observations from the southern hemisphere. We extracted the minima times from the light curves based on the Markov Chain Monte Carlo (MCMC) approach and obtained a new ephemeris. To provide modern photometric light curve solutions, we used the Physics of Eclipsing Binaries (Phoebe) software package and the MCMC approach. Light curve solutions yielded a system temperature ratio of 0.950, and we assumed a cold star-spot for the hotter star based on the O'Connell effect. This analysis reveals that AH Mic is a W-subtype W UMa contact system with a fill-out factor of 21.3% and a mass ratio of 2.32. The absolute physical parameters of the components are estimated by using the Gaia Early Data Release 3 (EDR3) parallax method to be M_h(M_Sun)=0.702(26), M_c(M_Sun)=1.629(104), R_h(R_Sun)=0.852(21), R_c(R_Sun)=1.240(28), L_h(L_Sun)=0.618(3) and L_c(L_Sun)=1.067(7). The orbital angular momentum of the AH Mic binary system was found to be 51.866(35). The components' positions of this system are plotted in the Hertzsprung-Russell (H-R) diagram., Comment: 6 figures, 4 tables, accepted by the Research in Astronomy and Astrophysics (RAA) journal

New relationships between the orbital period and some parameters of W Ursae Majoris (W UMa) type systems are presented in this study. To investigate the relationships, we calculated the absolute parameters of a sample of 118 systems. For this purpose, we used the parallax values obtained from the Gaia Early Data Release 3 (Gaia EDR3) star catalog for more precise calculations. The other required parameters, including the light curve solutions and the orbital period were derived from previous research. For some relationships, we added 86 systems from another study with an orbital period of less than 0.6 days to our sample, allowing us to increase the number of systems to 204. Therefore, the mass (M) values of each component along with all the other absolute parameters were recalculated for these contact systems. We used the Markov Chain Monte Carlo (MCMC) approach in order to gain the new orbital period-mass relations (P-M) per component, and added the temperature (T) to the process to acquire the new orbital period-temperature (P-T1) relation. We presented the orbital period behavior in terms of log(g) by new relations for each component. We have also obtained a model between the orbital period, the mass of the primary component and temperature (P-M1-T1) using the Artificial Neural Networks (ANN) method. Additionally, we present a model for the relationship between the orbital period and the mass ratio (P-q) by fitting a Multi-Layer Perceptron (MLP) regression model to a sample of the data collected from the literature., Comment: Accepted by MNRAS Journal

New CCD photometric observations and their investigation of the W UMa-type binary, V870 Ara, are presented. Light curves of the system were taken through BVI filters from the Congarinni Observatory in Australia. The new ephemeris is calculated based on seven new determined minimum times, together with the TESS data and others compiled from the literature. Photometric solutions determined by the Wilson-Devinney (W-D) code are combined with the Monte Carlo simulation to determine the adjustable parameters' uncertainties. These solutions suggest that V870 Ara is a contact binary system with a mass ratio of 0.082, a fillout factor of 96+-4 percent, and an inclination of 73.60+-0.64 degrees. The absolute parameters of V870 Ara were determined by combining the Gaia EDR3 parallax and photometric elements., Comment: 5 tables, 6 figs, accepted in the Open Astronomy Journal

The multi-color CCD photometric study of 27 Delta Scuti stars is presented. By using approximately three years of photometric observations, we obtained the times of maxima and magnitude changes during the observation time interval for each star. The ephemerides of our Delta Scuti stars were calculated based on the Markov Chain Monte Carlo (MCMC) method using the observed times of maxima and the period of the stars' oscillations. We used the Gaia EDR3 parallaxes to calculate the luminosities and also the absolute magnitudes of these Delta Scuti stars. The fundamental physical parameters of all the stars in our sample such as masses and radii were estimated. We determined the pulsation modes of the stars based on the pulsation constants. Moreover, the period-luminosity (P-L) relation of Delta Scuti stars was investigated and discussed. Then, by using a machine learning classification, new P-L relations for fundamental and overtone modes are presented., Comment: 5 Figures, 6 Tables, Accepted in the PASP journal

We present new BVR band photometric light curves of BO Aries obtained in 2020 and combined them with the Transiting Exoplanet Survey Satellite (TESS) light curves. We obtained times of minima based on Gaussian and Cauchy distributions and then applied the Monte Carlo Markov Chain (MCMC) method to measure the amount of uncertainty from our CCD photometry and TESS data. A new ephemeris of the binary system was computed employing 204 times of minimum. The light curves were analyzed using the Wilson-Devinney binary code combined with the Monte Carlo (MC) simulation. For this light curve solution, we considered a dark spot on the primary component. We conclude that this binary is an A-type system with a mass ratio of q=0.2074+-0.0001, an orbital inclination of i=82.18+-0.02 deg, and a fillout factor of f=75.7+-0.8%. Our results for the a(Rsun) and q parameters are consistent with the results of the Xu-Dong Zhang and Sheng-Bang Qian (2020) model. The absolute parameters of the two components were calculated and the distance estimate of the binary system was found to be 142+-9 pc., Comment: 7 Figures, 5 Tables, sent to New Astronomy journal

WASP-12 b, WASP-33 b, WASP-36 b, and WASP-46 b are four transiting planetary systems which we have studied. These systems' light curves were derived from observations made by the Transiting Light Exoplanet Survey Satellite (TESS) and some ground-based telescopes. We used Exofast-v1 to model these light curves and calculate mid-transit times. Also, we plotted TTV diagrams for them using derived mid-transit times and those available within the literature. O-C analysis of these timings enables us to refine the linear ephemeris of four systems. We measured WASP-12's tidal quality factor based on adding TESS data as Q*'=(2.13+-0.29)*10^5. According to the analysis, the orbital period of the WASP-46 b system is increasing. The WASP-36 b and WASP-33 b systems have not shown any obvious quadratic trend in their TTV diagrams. The increase in their period is most likely due to inaccurate liner ephemeris that has increased over time. So, more observations are needed to evaluate whether or not there is an orbital decay in the WASP-36 b and WASP-33 b systems., Comment: 14 figures, accepted at the Astronomy Letters journal

On 6 Jun 2020, Pluto's stellar occultation was successfully observed at a ground-based observatory and Pluto's atmospheric parameters were investigated. We used an atmospheric model of Pluto (DO15), assuming a spherical and transparent pure N2 atmosphere. Using ray-tracing code the stellar occultation light curve was satisfactorily fitted to this model. We found that Pluto's atmospheric pressure at the reference radius of 1215 km is 6.72+_0.21 {\mu}bar. Our estimated pressure shows a continuation of the increasing pressure studied in 2016 consistent with a seasonal volatile transport model. We concluded that the N2 condensation processes in the Sputnik Planitia glacier are increasing due to the heating of the N2 ice in this basin. This study's result was shown on the diagram of the annual evolution of atmospheric pressure., Comment: 4 figures, 2 tables

We performed the first light curve analysis of GW Leo and a new ephemeris is obtained for QT Boo. In the present photometric study of two contact binary systems, we found that the period of these binary systems is decreasing at a rate of dp/dt=-6.21*10^(-3) days yr^(-1) for GW Leo, and dp/dt=-4.72*10^(-3) days yr^(-1) for QT Boo, respectively. The light curve investigation also yields that the system GW Leo is a contact W UMa eclipsing binary with a photometric mass ratio of q=0.881+-0.030, a fillout factor of f=3%, and an inclination of 54.060+-0.066 deg. Due to the O'Connell effect which is known as asymmetries in the light curves' maxima, a cold spot is employed along with the solution. We also calculate the distance of GW Leo from the distance modulus formula as 465.58+-23 pc, which is relatively close to the quantity measured by the Gaia DR2 using the binary systems' parallax. Moreover, the positions of their components on the H-R diagram are represented., Comment: 8 figures, 7 tables, sent to the Astronomy Reports journal

A new ephemeris, period change analysis and light curve modeling of the W UMa-type eclipsing binary BF Pav are presented in this study. Light curves of the system taken in BVRI filters from two observatories in Australia and Argentina were modeled using the Wilson-Devinney code. The results of this analysis demonstrate that BF Pav is a contact binary system with a photometric mass ratio q=1.460+_0.014, a fillout factor f=12.5%, an inclination of 87.97+_0.45 deg and a cold spot on the secondary component. By using the distance modulus formula, the distance of BF Pav was calculated to be d=268+_18 pc which is in good agreement with the Gaia EDR3 distance. We obtain an orbital period increase at a rate of 0.142 s/century due to a quadratic trend in the O-C diagram. Also, an alternative sudden period jump probably has occurred which could be interpreted as a rapid mass transfer from the lower mass star to its companion about DeltaM=2.45*10^(-6) Msun. Furthermore, there is an oscillatory behavior with a period of 18.3+_0.3 yr. Since BF Pav does not seem to have significant magnetic activity, this behavior could be interpreted as the light-time effect caused by an undetected third body in this system. In this case, the probability for the third body to be a low mass star with M>=0.075 Msun or a brown dwarf is 5.4% and 94.6% respectively. If we assume i'=90deg, a_3=8.04+_0.33 AU. The mass of the secondary component was also determined using two different methods which result close to each other., Comment: 15 pages, 6 figures, 5 tables, Journal: accepted paper in RAA journal

In this research, the effect of Magnesium Fluoride (MgF2) Anti-Reflection (AR) layer was investigated in quantum dot sensitized solar cells (QDSCs). MgF2 nanoparticles with the dominant size of 20 nm were grown by a thermal evaporation method and a thin layer was formed on the front side of the fluorine-doped tin oxide (FTO) substrate. In order to study the effect of the AR layer on the efficiency of solar cells, this substrate was utilized in CdS QDSCs. In this conventional structure of QDSC, TiO2 nanocrystals (NCs) were applied on the FTO substrate, and then it was sensitized with CdS quantum dots (QDs). According to the results, the QDSCs with MgF2 AR layer represented the maximum Power Conversion Efficiency (PCE) of 3%. This efficiency was increased by about 47% compared to the reference cell without the AR layer. The reason is attributed to the presence of the AR layer and the reduction of incident light reflected from the surface of the solar cell., Comment: 12 pages, 10 figures, 1 table, sent it to Optical Materials

Among different models for determining the habitable zone (HZ) around a star, a Latitudinal Energy Balance Model (LEBM) is very beneficial due to its parametricity which keeps a good balance between complexity and simulation time. This flexibility makes the LEBM an excellent tool to assess the impact of some key physical parameters on the temperature and the habitability of a planet. Among different physical parameters, some of them, up until now, cannot be determined by any method such as the planet's spin obliquity, diurnal period, ocean-land ratio, and pressure level. Here we apply this model to study the effect of these unknown parameters on the habitability of three exoplanets located in the inner, outer, and middle of their optimistic HZ. Among the examined parameters, the impact of pressure is more straightforward. It has a nearly direct relation with temperature and also with the habitability in the case of a cold planet. The effect of other parameters is discussed with details. To quantify the impact of all these unknown parameters we utilize a statistical interface which provides us with the conditional probability on habitability status of each planet., Comment: 28 pages, 12 figures , 2 tables