arXiv - PHYS - Solar and Stellar Astrophysics最新文献

{"title":"On the formation height of low-corona and chromospheric channels of the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO)","authors":"Y. Sanjay, S. Krishna Prasad, R. Erdelyi, M. B. Korsos, D. Banerjee, P. S. Rawat","doi":"arxiv-2409.10451","DOIUrl":"https://doi.org/arxiv-2409.10451","url":null,"abstract":"The multi-wavelength data from the Solar Dynamics Observatory (SDO) is\u0000extensively used in studying the physics of the Sun and its atmosphere. In this\u0000study, we estimate the formation heights of low-corona and chromospheric\u0000channels of the Atmospheric Imaging Assembly (AIA) over the atmospheres of\u0000sunspot umbrae during the quiet condition period within 20 different active\u0000regions. The upward propagating slow magnetoacoustic waves (slow MAWs) of 3-min\u0000period, which are perpetually present in sunspots, are utilized for this\u0000purpose. Employing a cross-correlation technique, the most frequent time lag\u0000between different channel pairs is measured. By combining this information with\u0000the local sound speed obtained from the characteristic formation temperatures\u0000of individual channels, we estimate the respective formation heights. The\u0000median values of formation heights obtained across all active regions in our\u0000sample are 356, 368, 858, 1180, and 1470 km, respectively, for the AIA 1600\u0000{AA}, 1700 {AA}, 304 {AA}, 131 {AA}, and 171 {AA} channels. The\u0000corresponding ranges in the formation heights are 247 $--$ 453, 260 $--$ 468,\u0000575 $--$ 1155, 709 $--$ 1937, and 909 $--$ 2585 km, respectively. These\u0000values are measured with respect to the HMI continuum. We find the formation\u0000height of UV channels is quite stable (between 250 $--$ 500 km) and displays\u0000only a marginal difference between the AIA 1600 {AA} and 1700 {AA} during\u0000quiet conditions. On the other hand, the formation height of coronal channels\u0000is quite variable.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamical Evolution of Four Old Galactic Open Clusters traced by their constituent stars with textit{Gaia} DR3","authors":"Shanmugha Balan, Khushboo K Rao, Kaushar Vaidya, Manan Agarwal, Souradeep Bhattacharya","doi":"arxiv-2409.10186","DOIUrl":"https://doi.org/arxiv-2409.10186","url":null,"abstract":"We investigate the evolutionary stages of four open clusters, Berkeley 39,\u0000Collinder 261, NGC 6819, and NGC 7789, of ages ranging from 1.6 -- 6 Gyr. These\u0000clusters have previously been classified into dynamically young and\u0000intermediate age groups based on the segregation level of BSS with respect to\u0000red giant branch stars and main sequence stars, respectively. We identify\u0000members of these four clusters using the ML-MOC algorithm on Gaia DR3 data. To\u0000examine the relative segregation of cluster members of different evolutionary\u0000stages, we utilize cumulative radial distributions, proper motion\u0000distributions, and spatial distributions in galactocentric coordinates. Our\u0000analysis shows that Berkeley 39 and NGC 6819 exhibit moderate signs of\u0000population-wise segregation from evolved to less-evolved members. NGC 7789\u0000shows signs of mass segregation only in the cumulative radial distributions. On\u0000the other hand, Collinder 261 exhibits high segregation of BSS in the\u0000cumulative radial distribution, while other populations show the same level of\u0000segregation.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identifying activity induced RV periodicities and correlations using Central Line Moments","authors":"J. R. Barnes, S. V. Jeffers, C. A. Haswell, M. Damasso, F. Del Sordo, F. Liebing, M. Perger, G. Anglada-Escudé","doi":"arxiv-2409.10306","DOIUrl":"https://doi.org/arxiv-2409.10306","url":null,"abstract":"The radial velocity (RV) method of exoplanet detection requires mitigation of\u0000nuisance signals arising from stellar activity. Using analytic cool and facular\u0000spot models, we explore the use of central line moments (CLMs) for recovering\u0000and monitoring rotation induced RV variability. Different spot distribution\u0000patterns, photosphere-spot contrast ratios and the presence or absence of the\u0000convective blueshift lead to differences in CLM signals between M dwarfs and G\u0000dwarfs. Harmonics of the rotation period are often recovered with the highest\u0000power in standard periodogram analyses. By contrast, we show the true stellar\u0000rotation may be more reliably recovered with string length minimisation. For\u0000solar minimum activity levels, recovery of the stellar rotation signal from\u0000CLMs is found to require unfeasibly high signal-to-noise observations. The\u0000stellar rotation period can be recovered at solar maximum activity levels from\u0000CLMs for reasonable cross-correlation function (CCF) signal-to-noise ratios $>\u00001000 - 5000$. The CLMs can be used to recover and monitor stellar activity\u0000through their mutual correlations and correlations with RV and bisector inverse\u0000span. The skewness of a CCF, a measure of asymmetry, is described by the third\u0000CLM, $M_3$. Our noise-free simulations indicate the linear RV vs $M_3$\u0000correlation is up to 10 per cent higher than the RV vs bisector inverse span\u0000correlation. We find a corresponding $sim 5$ per cent increase in linear\u0000correlation for CARMENES observations of the M star, AU Mic. We also assess the\u0000effectiveness of the time derivative of the second CLM, $M_2$, for monitoring\u0000stellar activity.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling Pulsating Stars","authors":"Philip Masding, Robin Leadbeater","doi":"arxiv-2409.10116","DOIUrl":"https://doi.org/arxiv-2409.10116","url":null,"abstract":"Pulsating stars have been studied using non-linear hydrodynamic codes since\u0000the pioneering work of Robert Christy in the 1960s. Modern codes include\u0000improvements such as allowing for convection but there is a penalty in terms of\u0000computation speed and for some stars convection is not significant. In this\u0000work a new version of the Christy program has been developed which can run\u0000hundreds of star models to convergence in a day or two of computer time. This\u0000allows overall patterns of behaviour to be studied and suitable models for\u0000individual case stars to be identified. The star SZ Lyn was chosen as a test\u0000case for the model. Light curve and radial velocity data were obtained for this\u0000star using amateur equipment. A run of 625 parameter sets (mass, luminosity,\u0000effective temperature and hydrogen fraction) identified the best fit parameters\u0000for SZ Lyn. Model results show a good fit to the observed data in terms of\u0000amplitude, period and shape of the light and velocity curves. In this paper we\u0000report on the model developed by PM and radial velocity observations by RL.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"77 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The James Webb Space Telescope Absolute Flux Calibration. II. Mid-Infrared Instrument Imaging and Coronagraphy","authors":"Karl D. Gordon, G. C. Sloan, Macarena Garcia Marin, Mattia Libralato, George Rieke, Jonathan A. Aguilar, Ralph Bohlin, Misty Cracraft, Marjorie Decleir, Andras Gaspar, David R. Law, Alberto Noriega-Crespo, Michael Regan","doi":"arxiv-2409.10443","DOIUrl":"https://doi.org/arxiv-2409.10443","url":null,"abstract":"The absolute flux calibration of the Mid-Infrared Instrument Imaging and\u0000Coronagraphy is based on observations of multiple stars taken during the first\u00002.5 years of JWST operations. The observations were designed to ensure that the\u0000flux calibration is valid for a range of flux densities, different subarrays,\u0000and different types of stars. The flux calibration was measured by combining\u0000observed aperture photometry corrected to infinite aperture with predictions\u0000based on previous observations and models of stellar atmospheres. A subset of\u0000these observations were combined with model point-spread-functions to measure\u0000the corrections to infinite aperture. Variations in the calibration factor with\u0000time, flux density, background level, type of star, subarray, integration time,\u0000rate, and well depth were investigated, and the only significant variations\u0000were with time and subarray. Observations of the same star taken approximately\u0000every month revealed a modest time-dependent response loss seen mainly at the\u0000longest wavelengths. This loss is well characterized by a decaying exponential\u0000with a time constant of ~200 days. After correcting for the response loss, the\u0000band-dependent scatter around the corrected average (aka repeatability) was\u0000found to range from 0.1 to 1.2%. Signals in observations taken with different\u0000subarrays can be lower by up to 3.4% compared to FULL frame. After correcting\u0000for the time and subarray dependencies, the scatter in the calibration factors\u0000measured for individual stars ranges from 1 to 4% depending on the band. The\u0000formal uncertainties on the flux calibration averaged for all observations are\u00000.3 to 1.0%, with longer-wavelength bands generally having larger\u0000uncertainties.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photometry and spectroscopy of a deep Algol-like minimum of WW Vul in 2016","authors":"David Boyd","doi":"arxiv-2409.10073","DOIUrl":"https://doi.org/arxiv-2409.10073","url":null,"abstract":"We report analysis of photometry and spectroscopy of a deep Algol-like\u0000minimum of the pre-main-sequence star WW Vul in July and August 2016. This\u0000revealed substantial reddening due to absorption by circumstellar material.\u0000After dereddening, our spectra of WW Vul were consistent with spectral type A3V\u0000throughout the event. H{alpha} is normally in emission in WW Vul. During the\u0000minimum, H{alpha} emission dropped by ~30% and FWHM of the H{alpha} line\u0000reduced by ~15%.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142269220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inferring stellar parameters and their uncertainties from high-resolution spectroscopy using invertible neural networks","authors":"Nils Candebat, Giuseppe Germano Sacco, Laura Magrini, Francesco Belfiore, Mathieu Van-der-Swaelmen, Stefano Zibetti","doi":"arxiv-2409.10621","DOIUrl":"https://doi.org/arxiv-2409.10621","url":null,"abstract":"Context: New spectroscopic surveys will increase the number of astronomical\u0000objects requiring characterization by over tenfold.. Machine learning tools are\u0000required to address this data deluge in a fast and accurate fashion. Most\u0000machine learning algorithms can not estimate error directly, making them\u0000unsuitable for reliable science. Aims: We aim to train a supervised deep-learning algorithm tailored for\u0000high-resolution observational stellar spectra. This algorithm accurately infer\u0000precise estimates while providing coherent estimates of uncertainties by\u0000leveraging information from both the neural network and the spectra. Methods: We train a conditional Invertible Neural Network (cINN) on\u0000observational spectroscopic data obtained from the GIRAFFE spectrograph (HR10\u0000and HR21 setups) within the Gaia-ESO survey. A key features of cINN is its\u0000ability to produce the Bayesian posterior distribution of parameters for each\u0000spectrum. By analyzing this distribution, we inferred parameters and their\u0000uncertainties. Several tests have been applied to study how parameters and\u0000errors are estimated. Results: We achieved an accuracy of 28K in $T_{text{eff}}$, 0.06 dex in\u0000$log g$, 0.03 dex in $[text{Fe/H}]$, and between 0.05 dex and 0.17 dex for\u0000the other abundances for high quality spectra. Accuracy remains stable with low\u0000signal-to-noise ratio spectra. The uncertainties obtained are well within the\u0000same order of magnitude. The network accurately reproduces astrophysical\u0000relationships both on the scale of the Milky Way and within smaller star\u0000clusters. We created a table containing the new parameters generated by our\u0000cINN. Conclusion: This neural network represents a compelling proposition for\u0000future astronomical surveys. These coherent derived uncertainties make it\u0000possible to reuse these estimates in other works as Bayesian priors and thus\u0000present a solid basis for future work.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D ISM structure challenges the Serkowski relation","authors":"Nikolaos Mandarakas, Konstantinos Tassis, Raphael Skalidis","doi":"arxiv-2409.10317","DOIUrl":"https://doi.org/arxiv-2409.10317","url":null,"abstract":"The Serkowski relation is the cornerstone of studies of starlight\u0000polarization as a function of wavelength. Although empirical, its extensive use\u0000since its inception to describe polarization induced by interstellar dust has\u0000elevated the relation to the status of an indisputable \"law\", serving as the\u0000benchmark for validating interstellar dust grain models. We revisit the effects\u0000of the 3D structure of the interstellar medium (ISM) on the wavelength\u0000dependence of interstellar polarization. We use analytical models to show how\u0000the wavelength dependence of both the polarization fraction and direction is\u0000affected by the presence of multiple clouds along the line of sight (LOS),\u0000accounting for recent developments in dust distribution modelling and utilizing\u0000an expanded archive of stellar polarization measurements. We highlight concrete\u0000examples of stars whose polarization profiles are severely affected by LOS\u0000variations of the dust grain and magnetic field properties, and we provide a\u0000recipe to accurately fit multiple cloud Serkowski models to such cases. We\u0000present, for the first time, compelling observational evidence that the 3D\u0000structure of the magnetized ISM often results to the violation of the Serkowski\u0000relation. We show that 3D effects impact interstellar cloud parameters derived\u0000from Serkowski fits. In particular, the dust size distribution in single -\u0000cloud sightlines may differ from analyses that ignore 3D effects, with\u0000important implications for dust modelling in the Galaxy. Our results suggest\u0000that multiband stellar polarization measurements offer an independent probe of\u0000the LOS variations of the magnetic field, constituting a valuable new tool for\u0000the 3D cartography of the ISM. We caution that, unless 3D effects are\u0000explicitly accounted for, a poor fit to the Serkowski relation does not, by\u0000itself, constitute conclusive evidence that a star is intrinsically polarized.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TV Mon - post mass transfer Algol type binary with $δ$ Scuti pulsations in primary component","authors":"Mikhail Kovalev, Zhenwei Li, Jianping Xiong, Azizbek Matekov, Zhang Bo, Xuefei Chen, Zhanwen Han","doi":"arxiv-2409.09902","DOIUrl":"https://doi.org/arxiv-2409.09902","url":null,"abstract":"We present a study of the detached eclipsing binary TV~Mon using spectra from\u0000the LAMOST medium-resolution survey and ASAS-SN, CoRoT photometry. We applied\u0000multiple-epochs spectral fitting to derive RV and spectral parameters. The\u0000analysis of eclipses in CoRoT data told us relative sizes of the stellar\u0000components and almost edge-on circular orbit. Combining spectral and\u0000photometrical solution we estimated masses and radii of the components:\u0000$M_{A,B}=2.063pm0.033,~0.218pm0.004~M_odot$,\u0000$R_{A,B}=2.427pm0.014,~2.901pm0.016~R_odot$. SED analysis and Gaia parallax\u0000allowed us to get estimation of temperatures\u0000$T_{A,B}=7624^{+194}_{-174},~5184^{+130}_{-123}$ K and distance $d=907pm11$\u0000pc. We identified three $delta$ Scuti type pulsation frequencies in primary\u0000component, while we also suspect TV~Mon having a long period variability with\u0000period $P_{rm long}sim128$ days and spot activity in secondary component.\u0000This system experienced intensive mass transfer and mass ratio reversal in the\u0000past, currently showing no signs of mass transfer in the spectra. The low mass\u0000component will lose its outer envelope and shrink to the helium white dwarf,\u0000which mass and orbital period are in good agreement with evolutionary models\u0000predictions.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the time variability of the Solar Wind using LOFAR pulsar data","authors":"S. C. Susarla, A. Chalumeau, C. Tiburzi, E. F. Keane, J. P. W. Verbiest, J. S. Hazboun, M. A. Krishnakumar, F. Iraci, G. M. Shaifullah, A. Golden, A. S. Bak Nielsen, J. Donner, J. M. Grießmeier, M. J. Keith, S. Osłowski, N. K. Porayko, M. Serylak, J. M. Anderson, M. Brüggen, B. Ciardi, R. J. Dettmar, M. Hoeft, J. Künsemöller, D. Schwarz, C. Vocks","doi":"arxiv-2409.09838","DOIUrl":"https://doi.org/arxiv-2409.09838","url":null,"abstract":"High-precision pulsar timing is highly dependent on precise and accurate\u0000modeling of any effects that impact the data. It was shown that commonly used\u0000Solar Wind models do not accurately account for variability in the amplitude of\u0000the Solar wind on both short and long time scales. In this study, we test and\u0000validate a new, cutting-edge Solar wind modeling method included in the\u0000texttt{enterprise} software suite through extended simulations, and we apply\u0000it to investigate temporal variability in LOFAR data. Our model testing scheme\u0000in itself provides an invaluable asset for pulsar timing array (PTA)\u0000experiments. As improperly accounting for the solar wind signature in pulsar\u0000data can induce false-positive signals, it is of fundamental importance to\u0000include in any such investigations. We employ a Bayesian approach utilizing a\u0000continuously varying Gaussian process to model the solar wind referred to as\u0000Solar Wind Gaussian Process (SWGP). We conduct noise analysis on eight pulsars\u0000from the LOFAR dataset with most pulsars having a timespan of $sim 11$ years\u0000encompassing one full solar activity cycle. Our analysis reveals a strong\u0000correlation between the electron density at 1 AU and the ecliptic latitude\u0000(ELAT) of the pulsar. Pulsars with $|ELAT|< 3^{circ}$ exhibit significantly\u0000higher average electron densities. We observe distinct temporal patterns in\u0000electron densities in different pulsars. In particular, pulsars within $|ELAT|<\u00003^{circ}$ exhibit similar temporal variations, while the electron densities of\u0000those outside this range correlate with the solar activity cycle. The\u0000continuous variability in electron density offered in this model represents a\u0000substantial improvement over previous models, which assume a single value for\u0000piece-wise bins of time. This advancement holds promise for solar wind modeling\u0000in future International Pulsar Timing Array data combinations.","PeriodicalId":501068,"journal":{"name":"arXiv - PHYS - Solar and Stellar Astrophysics","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142257987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}