[論文レビュー] SNeSCOPE - a python package for shock cooling fitting using the model of Morag et al 2024

I. Irani|arXiv (Cornell University)|Oct 25, 2023

Gamma-ray bursts and supernovae被引用数 4

ひとこと要約

本論文は、モラグら2024年のフレームワークを用いて、Type II超新星の初期紫外・可視光光曲線に衝撃冷却モデルをフィットするためのPythonパッケージSNeSCOPEを紹介する。初期のUV-可視光色とブラックボディ的変化が球対称な衝撃冷却と整合的であり、赤超巨星の前身星の66%が観測されたフィールドRSG分布と一致するブレイクアウト半径を持つことが判明したが、物質密度の制限や膨張したエンvelopeによる影響により、明るさバイアスが半径分布をより大きな半径側にずらしている。

ABSTRACT

SNeSCOPE - SuperNovae Shock Cooling Observations Parameter Estimator Documentation SNeSCOPE is a python package for modeling supernova light curves using the analytic models of Morag et al 2023 and Morag et al 2024. Installation to install, git clone the repository. Then run from within the SNeSCOPE directory (where the script setup.py is) python setup.py install Alternatively, use pip pip install SNeSCOPE add simulation data files Use the following link to download the MG simulatiosn used for constructing the covariance matrix for the likelihood function: https://www.dropbox.com/scl/fi/kawt98t2lri5j90o61u60/RSG_batch_R03_20_removed_lines_Z1.mat?rlkey=1hnpbgiayol7jtu4cn4895slg&dl=0 and for the keys: https://www.dropbox.com/scl/fi/o22vj00kjskp9gk6ae2h1/RSG_batch_R03_20_removed_lines_Z1_key.mat?rlkey=kop5iq609h10pgkgsnycuvjyx&dl=0 If these links do not work for any reason, the files can be found in the zenodo repository linked in the bottom of this readme In addition to these, the filter transmission data I use is collected in the Filters folder avilable in this repository and in the zenodo repository. running the script To run pre exsiting script, modify the parameter files (e.g., see in tests). You will modify paths, SN parameters (e.g., distance, redshift, extinction), package options, and the photometric filters used while observing (an extensive folder is added, but you can always add more. Make sure to update the plotting parameters accordingly). If you encounter errors at this point, make sure you have the correct paths and consider moving from relative to absolute paths. Then run the script fit_SC.py, e.g., from the SNeSCOPE directory (for a unix based system): python ./scripts/fit_SC.py --path_params ./tests/params_2020jfo.py or (if using windows) python .\scripts\fit_SC.py --path_params . ests\params_2020jfo.py As the script is currently written, it requires a data file containing magnituds, fluxes, instruments and filters as is shown in the example test files. The script uses a non-rectangular prior on the recombination time of Hydrogen at a photospheric temperature of roughly t_rec 0.7 eV~ 8000K. Given the typical deviations from blackbody and given a mild amount of host extinction (up to E(B-V) = 0.2), a blackboyd fit assuming E(B-V) = 0 mag at 8000K can give anywhere between 5000 and 10000 K. I recommend to first fix the extinction to lower than 0.2, using the color curves of Irani 2024. Then add a dates files. This is a list of times (JD) where E(B-V) = 0 blackbody fits are made, and then used as priors. The script will run the fitter in the following steps: blackbody fits prepare covariance matrix for likelihood function using the light curve sampling provided fit the data get the results. re-fit a blackbody using the fit host-extinciton save the results as a pickle object plot calculate physical parameters and save to a table (for a full description of these parameters, see Irani 2024, and Morag 2024, and references therein). There are 4 plots which are provided. Light curve fits. These include a vertical line indicating the early validity time of the model (the time the breakout pulse is over and homologous expansion is reached). I also provide these plots with a logarithmic axis, which are more convenient for high cadence sampling of the early light curves. Blackbody fits compared to the model predictions. These are compared to the new blackbody fits, using the fit E(B-V) (and Rv, if fitted). A good fit should also fit the blackbody temperature and radius reasonable well, although some deviations are expected as the SED is not a perfect blackbody. corner plots SED plot - These can be used to evaluate the observed and model SED at various epochs. The different lines are both the blackbody and the frequency dependent formulas smapled from the posterior. Keep in mind sometimes, due to a low mass envelope or fast V*, the model can be no longer valid at the lowest temperature plotted in these plots. Python version python 3 Required python packages numpy dynesty matplotlib scipy astropy numba astropy os pandas Support I'm happy to provide support in setting up the package and interpreting its results. You can contact me at [e-mail]. For the most up to date version of the package, please visit the github repository at https://github.com/idoirani/shock_cooling. Credit If you are using SNeSCOPE, please cite the following papers: light curve fitter: Irani et al 2024, "the early UV light curves of Type II SNe" @ARTICLE{2023arXiv231016885I, author = {{Irani}, Ido and {Morag}, Jonathan and {Gal-Yam}, Avishay and {Waxman}, Eli and {Schulze}, Steve and {Sollerman}, Jesper and {Hinds}, K-Ryan and {Perley}, Daniel A. and {Chen}, Ping and {Strotjohann}, Nora L. and {Yaron}, Ofer and {Zimmerman}, Erez A. and {Bruch}, Rachel and {Ofek}, Eran O. and {Soumagnac}, Maayane T. and {Yang}, Yi and {Groom}, Steven L. and {Masci}, Frank J. and {Riddle}, Reed and {Bellm}, Eric C. and {Hale}, David}, title = "{The Early Ultraviolet Light-Curves of Type II Supernovae and the Radii of Their Progenitor Stars}", journal = {arXiv e-prints}, keywords = {Astrophysics - High Energy Astrophysical Phenomena}, year = 2023, month = oct, eid = {arXiv:2310.16885}, pages = {arXiv:2310.16885}, doi = {10.48550/arXiv.2310.16885}, archivePrefix = {arXiv}, eprint = {2310.16885}, primaryClass = {astro-ph.HE}, adsurl = {https://ui.adsabs.harvard.edu/abs/2023arXiv231016885I}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} } analytic model for T,L evolution: Morag et al 2023 "Shock cooling emission from explosions of red super-giants: I. A numerically calibrated analytic model" @ARTICLE{2023MNRAS.522.2764M, author = {{Morag}, Jonathan and {Sapir}, Nir and {Waxman}, Eli}, title = "{Shock cooling emission from explosions of red supergiants - I. A numerically calibrated analytic model}", journal = {\mnras}, keywords = {shock waves, supernovae: general, Astrophysics - High Energy Astrophysical Phenomena}, year = 2023, month = jun, volume = {522}, number = {2}, pages = {2764-2776}, doi = {10.1093/mnras/stad899}, archivePrefix = {arXiv}, eprint = {2207.06179}, primaryClass = {astro-ph.HE}, adsurl = {https://ui.adsabs.harvard.edu/abs/2023MNRAS.522.2764M}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} } deviations from blackbody: Morag et al 2024, "Shock cooling emission from explosions of red super-giants: II. An analytic model of deviations from blackbody emission" @ARTICLE{2024MNRAS.528.7137M, author = {{Morag}, Jonathan and {Irani}, Ido and {Sapir}, Nir and {Waxman}, Eli}, title = "{Shock cooling emission from explosions of red supergiants: II. An analytic model of deviations from blackbody emission}", journal = {\mnras}, keywords = {radiation: dynamics, radiative transfer, shock waves, transients: supernovae, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Solar and Stellar Astrophysics}, year = 2024, month = mar, volume = {528}, number = {4}, pages = {7137-7155}, doi = {10.1093/mnras/stae374}, archivePrefix = {arXiv}, eprint = {2307.05598}, primaryClass = {astro-ph.HE}, adsurl = {https://ui.adsabs.harvard.edu/abs/2024MNRAS.528.7137M}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} } Variable validity domain: Soumagnac et al 2020 "SN 2018fif: The Explosion of a Large Red Supergiant Discovered in Its Infancy by the Zwicky Transient Facility" @ARTICLE{2020ApJ...902....6S, author = {{Soumagnac}, Maayane T. and {Ganot}, Noam and {Irani}, Ido and {Gal-yam}, Avishay and {Ofek}, Eran O. and {Waxman}, Eli and {Morag}, Jonathan and {Yaron}, Ofer and {Schulze}, Steve and {Yang}, Yi and {Rubin}, Adam and {Cenko}, S. Bradley and {Sollerman}, Jesper and {Perley}, Daniel A. and {Fremling}, Christoffer and {Nugent}, Peter and {Neill}, James D. and {Karamehmetoglu}, Emir and {Bellm}, Eric C. and {Bruch}, Rachel J. and {Burruss}, Rick and {Cunningham}, Virginia and {Dekany}, Richard and {Golkhou}, V. Zach and {Graham}, Matthew J. and {Kasliwal}, Mansi M. and {Konidaris}, Nicholas P. and {Kulkarni}, Shrinivas R. and {Kupfer}, Thomas and {Laher}, Russ R. and {Masci}, Frank J. and {Riddle}, Reed and {Rigault}, Mickael and {Rusholme}, Ben and {van Roestel}, Jan and {Zackay}, Barak}, title = "{SN 2018fif: The Explosion of a Large Red Supergiant Discovered in Its Infancy by the Zwicky Transient Facility}", journal = {\apj}, keywords = {Supernovae, Type II supernovae, Astronomy data modeling, Observational astronomy, Ultraviolet transient sources, Transient sources, 1668, 1731, 1859, 1145, 1854, 1851, Astrophysics - High Energy Astrophysical Phenomena}, year = 2020, month = oct, volume = {902}, number = {1}, eid = {6}, pages = {6}, doi = {10.3847/1538-4357/abb247}, archivePrefix = {arXiv}, eprint = {1907.11252}, primaryClass = {astro-ph.HE}, adsurl = {https://ui.adsabs.harvard.edu/abs/2020ApJ...902....6S}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} } If using Piro 2021 "Shock Cooling Emission from Extended Material Revisited" @ARTICLE{2021ApJ...909..209P, author = {{Piro}, Anthony L. and {Haynie}, Annastasia and {Yao}, Yuhan}, title = "{Shock Cooling Emission from Extended Material Revisited}", journal = {\apj}, keywords = {Radiative transfer, Supernovae, 1335, 1668, Astrophysics - High Energy Astrophysical Phenomena}, year = 2021, month = mar, volume = {909}, number = {2}, ei

研究の動機と目的

• 多バンドUVおよび可視光データを用いて、初期超新星光曲線に衝撃冷却モデルをフィットするための堅牢なフレームワークの開発。
• Type II超新星における衝撃ブレイクアウト位相の分析を通じて、前身星の半径と爆発エネルギーを制約すること。
• 初期光曲線を支配する主要要因が衝撃冷却か、周囲星間物質（CSM）との相互作用かを区別すること。
• X線観測結果および上限値を用いて、拡張したCSMの密度および質量放出レートの制約を導出すること。
• スペクトルモデルに依存せずに、観測されたUV-可視光色の時間的変化から宿主銀河の減光を経験的に補正し、フィッティングフレームワークの妥当性を検証すること。

提案手法

• SNeSCOPEパッケージは、モラグら2024年の衝撃冷却モデルを実装し、Zwicky Transient Facility（ZTF）のUV、可視光、X線データを含む多バンド光曲線にフィットする。
• モデルは、前身星の半径、密度プロファイル、爆発エネルギーに基づいた衝撃ブレイクアウト timescale と輝度の時間的変化を用い、主なパラメータとして $ R_{bo} $, $ v_{bo} $, $ E_{ ext{exp}} $, および $ M_{ ext{ej}} $ を含む。
• 事後分布の推定と不確実性の評価を可能にするために、dynestyライブラリを用いたネストドサンプリングによるフィッティングが実施される。
• スペクトルモデルに依存しない経験的宿主減光補正は、観測されたUV-可視光色の時間的変化から導出される。
• X線データは、エネルギー収支と放射効率を仮定することで、$ \tilde{10^{15}} $ cmにおけるCSM密度をスペクトルフィッティングに依存せずに制約する。
• 多群放射流体力学シミュレーションを用いた検証により、半径と速度に関して入力パラメータが20%以内で偏りなく回復されることを示した。

Figure 1: In the top panel, we show the distribution of distances to the SNe in our sample, compared to the distribution of BTS SNe II. We truncate the plot at 400 Mpc for clarity. In the bottom panel, we show the distribution of peak $r$ -band magnitude compared to BTS SNe II. In both panels, we sh

実験結果

リサーチクエスチョン

• RQ1 フラッシュイオン化特徴に依存せずに、初期UV-可視光光曲線が球対称な衝撃冷却モデルで一貫して説明可能か？
• RQ2 Type II超新星における前身星のブレイクアウト半径の分布は何か？また、観測された赤超巨星集団とどのように関係しているか？
• RQ3 周囲星間物質（CSM）との相互作用や膨張したエンベロープは、初期光曲線の上昇およびブレイクアウト特性にどの程度の影響を及ぼすか？
• RQ4 X線観測結果および上限値を用いて、前身星の質量放出レートとCSM密度にどの程度の制約を課せるか？
• RQ5 観測上の明るさバイアスは、サンプルにおけるブレイクアウト半径分布にどのように影響を及ぼすか？

主な発見

• 34個のSNe IIの初期UV-可視光色およびブラックボディ的変化は、フラッシュイオン化特徴にかかわらず、球対称な衝撃冷却モデルと整合的である。
• SNeSCOPEは、多群シミュレーションからの入力パラメータを半径および速度に関して20%未満のバイアスで回復でき、フィッティングフレームワークの妥当性が裏付けられた。
• サンプルの約半数（17/34）が $ <10^{14} $ cm のブレイクアウト半径を持つモデルで最もよくフィットするが、残りの半数は $ >10^{14} $ cm を必要としており、前身星の二峰性構造を示唆している。
• 高半径フィットは最初の1日間に不自然に遅い上昇を予測しており、これは大半のブレイクアウトイベントが膨張したエンベロープまたは急峻なCSM密度プロファイルに起因している可能性を示している。
• X線観測結果および上限値により、CSM質量放出レートが $ \dot{M} < 10^{-4} M_{\odot} \, \text{yr}^{-1} $ に制限され、これは大多数のSNe IIの前身星がCSMを閉じ込めていることを示している。
• 観測されたブレイクアウト半径分布は明るさバイアスによりより大きな半径側にずれているが、補正後、66%のRSGがフィールドRSG分布と一致する半径で爆発しており、さらに大きな半径への尾を示すのはCSMの影響による可能性がある。

Figure 2: The times of first detection relative to the estimated time of zero flux, in UV and in optical bands. Both a histogram and a cumulative distribution is shown.