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href='/hst/instrumentation/acs/proposing/dither-strategies/acs-hrc-mosaic-box' class="offcanvas__section-link" >ACS-HRC-MOSAIC-BOX</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/acs/proposing/dither-strategies/acs-sbc-dither-line' class="offcanvas__section-link" >ACS-SBC-DITHER-LINE</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/acs/proposing/dither-strategies/acs-sbc-dither-box' class="offcanvas__section-link" >ACS-SBC-DITHER-BOX</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/acs/proposing/dither-strategies/acs-sbc-mosaic-line' class="offcanvas__section-link" >ACS-SBC-MOSAIC-LINE</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/acs/proposing/dither-strategies/acs-sbc-mosaic-box' class="offcanvas__section-link" >ACS-SBC-MOSAIC-BOX</a></li></ul></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/acs/proposing/exception-report-instructions' class="offcanvas__section-link" >Exception Report Instructions</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/acs/data-analysis' class="offcanvas__section-link" >Data Analysis</a><button class="offcanvas__section-toggle" id="Data_Analysis_21_control" type="button" aria-label="Data Analysis submenu" aria-controls="Data_Analysis_21_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Data_Analysis_21_section" class="offcanvas__list" data-level="5" aria-labelledby="Data_Analysis_21_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/acs/data-analysis/aperture-corrections' 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data-level="5" aria-labelledby="Software_Tools_23_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/acs/software-tools/analysis-tools' class="offcanvas__section-link" >Analysis Tools</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/acs/software-tools/calibration-tools' class="offcanvas__section-link" >Calibration Tools</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='http://drizzlepac.readthedocs.io/en/deployment/index.html' class="offcanvas__section-link" target='_blank' >DrizzlePac</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/acs/documentation' class="offcanvas__section-link" >Documentation</a><button class="offcanvas__section-toggle" id="Documentation_24_control" type="button" aria-label="Documentation submenu" aria-controls="Documentation_24_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Documentation_24_section" class="offcanvas__list" data-level="5" aria-labelledby="Documentation_24_control"><li class="offcanvas__item noChildren firstInLevel"><a href='https://hst-docs.stsci.edu/acsihb' class="offcanvas__section-link" target='_blank' >ACS Instrument Handbook</a></li><li class="offcanvas__item noChildren"><a href='https://hst-docs.stsci.edu/acsdhb' class="offcanvas__section-link" target='_blank' >ACS Data Handbook</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/acs/documentation/instrument-science-reports-isrs' class="offcanvas__section-link" >Instrument Science Reports (ISRs)</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/acs/documentation/stsci-analysis-newsletter-stan' class="offcanvas__section-link" 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href='/hst/instrumentation/acs/documentation/instrument-science-reports-isrs' class="offcanvas__section-link" target='_parent' >ACS ISRs</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/acs/documentation/stsci-analysis-newsletter-stan' class="offcanvas__section-link" target='_parent' >ACS STANs</a></li><li class="offcanvas__item noChildren"><a href='http://etc.stsci.edu/etc/input/acs/imaging/' class="offcanvas__section-link" target='_blank' >ACS Imaging ETC</a></li><li class="offcanvas__item noChildren"><a href='http://etc.stsci.edu/etc/input/acs/spectroscopic/' class="offcanvas__section-link" target='_blank' >ACS Spectroscopic ETC</a></li><li class="offcanvas__item noChildren"><a href='http://etc.stsci.edu/etc/input/acs/rampfilter/' class="offcanvas__section-link" target='_blank' >ACS Ramp Filter ETC</a></li><li class="offcanvas__item noChildren"><a href='/hst/proposing' class="offcanvas__section-link" target='_self' >HST Proposing</a></li><li 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xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Cosmic_Origins_Spectrograph_26_section" class="offcanvas__list" data-level="4" aria-labelledby="Cosmic_Origins_Spectrograph_26_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/cos/instrument-design' class="offcanvas__section-link" >Instrument Design</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/cos/performance' class="offcanvas__section-link" >Performance</a><button class="offcanvas__section-toggle" id="Performance_27_control" type="button" aria-label="Performance submenu" aria-controls="Performance_27_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Performance_27_section" class="offcanvas__list" data-level="5" aria-labelledby="Performance_27_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/cos/performance/monitoring' class="offcanvas__section-link" >Monitoring</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/performance/sensitivity' class="offcanvas__section-link" >Sensitivity</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/cos/performance/spectral-resolution' class="offcanvas__section-link" >Spectral Resolution and Line Spread Functions</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/cos/proposing' class="offcanvas__section-link" >Proposing</a><button class="offcanvas__section-toggle" id="Proposing_28_control" type="button" aria-label="Proposing submenu" aria-controls="Proposing_28_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Proposing_28_section" class="offcanvas__list" data-level="5" aria-labelledby="Proposing_28_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/cos/proposing/cos2025-policies' class="offcanvas__section-link" >COS2025 Policies</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/proposing/observing-strategies' class="offcanvas__section-link" >Observing Strategies</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/cos/proposing/wavelength-tool' class="offcanvas__section-link" >Wavelength Tool</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/data-analysis--software-tools' class="offcanvas__section-link" >Data Analysis & Software Tools</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/cos/calibration' class="offcanvas__section-link" >Calibration</a><button class="offcanvas__section-toggle" id="Calibration_29_control" type="button" aria-label="Calibration submenu" aria-controls="Calibration_29_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Calibration_29_section" class="offcanvas__list" data-level="5" aria-labelledby="Calibration_29_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/cos/calibration/airglow' class="offcanvas__section-link" >Airglow</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-31-calibration-plan' class="offcanvas__section-link" >Cycle 31 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-30-calibration-plan' class="offcanvas__section-link" >Cycle 30 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-29-calibration-plan' class="offcanvas__section-link" >Cycle 29 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-28-calibration-plan' class="offcanvas__section-link" >Cycle 28 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-27-calibration-plan' class="offcanvas__section-link" >Cycle 27 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-26-calibration-plan' class="offcanvas__section-link" >Cycle 26 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-25-calibration-plan' class="offcanvas__section-link" >Cycle 25 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-24-calibration-plan' class="offcanvas__section-link" >Cycle 24 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-23-calibration-plan' class="offcanvas__section-link" >Cycle 23 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-22-calibration-plan' class="offcanvas__section-link" >Cycle 22 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-21-calibration-plan' class="offcanvas__section-link" >Cycle 21 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-20-calibration-plan' class="offcanvas__section-link" >Cycle 20 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-19-calibration-plan' class="offcanvas__section-link" >Cycle 19 Calibration Plan</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/calibration/cycle-18-calibration-plan' class="offcanvas__section-link" >Cycle 18 Calibration Plan</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/cos/calibration/cycle-17-calibration-plan' class="offcanvas__section-link" >Cycle 17 Calibration Plan</a></li></ul></li><li class="offcanvas__item hasChildren lastInLevel"><a href='/hst/instrumentation/cos/documentation' class="offcanvas__section-link" >Documentation</a><button class="offcanvas__section-toggle" id="Documentation_30_control" type="button" aria-label="Documentation submenu" aria-controls="Documentation_30_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Documentation_30_section" class="offcanvas__list" data-level="5" aria-labelledby="Documentation_30_control"><li class="offcanvas__item noChildren firstInLevel"><a href='https://hst-docs.stsci.edu/display/COSIHB' class="offcanvas__section-link" target='_blank' >COS Instrument Handbook</a></li><li class="offcanvas__item noChildren"><a href='https://hst-docs.stsci.edu/display/COSDHB' class="offcanvas__section-link" target='_blank' >COS Data Handbook</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/documentation/instrument-science-reports-isrs' class="offcanvas__section-link" >Instrument Science Reports (ISRs)</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/documentation/stsci-analysis-newsletter-stan' class="offcanvas__section-link" >STScI Analysis Newsletter (STAN)</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/documentation/exception-report-instructions' class="offcanvas__section-link" >Exception Report Instructions</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/documentation/conference-posters' class="offcanvas__section-link" >Conference Posters</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/cos/documentation/calcos-release-notes' class="offcanvas__section-link" >CalCOS Release Notes</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/cos/documentation/notebooks' class="offcanvas__section-link" >Notebooks</a></li></ul></li></ul></li><li 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class="offcanvas__section-link" >Instrument Design</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/fgs/performance' class="offcanvas__section-link" >Performance</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/fgs/proposing' class="offcanvas__section-link" >Proposing</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/fgs/data-analysis' class="offcanvas__section-link" >Data Analysis</a><button class="offcanvas__section-toggle" id="Data_Analysis_32_control" type="button" aria-label="Data Analysis submenu" aria-controls="Data_Analysis_32_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Data_Analysis_32_section" class="offcanvas__list" data-level="5" aria-labelledby="Data_Analysis_32_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/fgs/data-analysis/software-tools' class="offcanvas__section-link" >Software Tools</a></li></ul></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/fgs/documentation' class="offcanvas__section-link" >Documentation</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/stis' class="offcanvas__section-link" >Space Telescope Imaging Spectrograph</a><button class="offcanvas__section-toggle" id="Space_Telescope_Imaging_Spectrograph_33_control" type="button" aria-label="Space Telescope Imaging Spectrograph submenu" aria-controls="Space_Telescope_Imaging_Spectrograph_33_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Space_Telescope_Imaging_Spectrograph_33_section" class="offcanvas__list" data-level="4" aria-labelledby="Space_Telescope_Imaging_Spectrograph_33_control"><li class="offcanvas__item hasChildren firstInLevel"><a href='/hst/instrumentation/stis/instrument-design' class="offcanvas__section-link" >Instrument Design</a><button class="offcanvas__section-toggle" id="Instrument_Design_34_control" type="button" aria-label="Instrument Design submenu" aria-controls="Instrument_Design_34_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Instrument_Design_34_section" class="offcanvas__list" data-level="5" aria-labelledby="Instrument_Design_34_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/stis/instrument-design/apertures' class="offcanvas__section-link" >Apertures</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/instrument-design/detectors' class="offcanvas__section-link" >Detectors</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/instrument-design/filters' class="offcanvas__section-link" >Filters</a></li><li class="offcanvas__item hasChildren lastInLevel"><a href='/hst/instrumentation/stis/instrument-design/gratings--prism' class="offcanvas__section-link" >Gratings / Prism</a><button class="offcanvas__section-toggle" id="Gratings_-_Prism_35_control" type="button" aria-label="Gratings / Prism submenu" aria-controls="Gratings_-_Prism_35_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Gratings_-_Prism_35_section" class="offcanvas__list" data-level="6" aria-labelledby="Gratings_-_Prism_35_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/stis/instrument-design/gratings--prism/spectral-format-plots' class="offcanvas__section-link" >Spectral Format Plots</a></li></ul></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/stis/performance' class="offcanvas__section-link" >Performance</a><button class="offcanvas__section-toggle" id="Performance_36_control" type="button" aria-label="Performance submenu" aria-controls="Performance_36_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Performance_36_section" class="offcanvas__list" data-level="5" aria-labelledby="Performance_36_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/stis/performance/anomalies' class="offcanvas__section-link" >Anomalies</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/performance/image-quality' class="offcanvas__section-link" >Image Quality</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/performance/monitoring' class="offcanvas__section-link" >Monitoring</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/performance/sensitivity' class="offcanvas__section-link" >Sensitivity</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/performance/spectral-resolution' class="offcanvas__section-link" >Spectral Resolution</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/performance/throughput' class="offcanvas__section-link" >Throughput</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/stis/performance/background-noise' class="offcanvas__section-link" >Background Noise</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/stis/proposing' class="offcanvas__section-link" >Proposing</a><button class="offcanvas__section-toggle" id="Proposing_37_control" type="button" aria-label="Proposing submenu" aria-controls="Proposing_37_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Proposing_37_section" class="offcanvas__list" data-level="5" aria-labelledby="Proposing_37_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/stis/proposing/go-wavecal-aperture-selection' class="offcanvas__section-link" >GO Wavecal Aperture Selection</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/stis/proposing/exception-reports' class="offcanvas__section-link" >Exception Reports</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/stis/observing-strategies' class="offcanvas__section-link" >Observing Strategies</a><button class="offcanvas__section-toggle" id="Observing_Strategies_38_control" type="button" aria-label="Observing Strategies submenu" aria-controls="Observing_Strategies_38_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Observing_Strategies_38_section" class="offcanvas__list" data-level="5" aria-labelledby="Observing_Strategies_38_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/stis/observing-strategies/target-acquisition' class="offcanvas__section-link" >Target Acquisition</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/observing-strategies/spectroscopy' class="offcanvas__section-link" >Spectroscopy</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/observing-strategies/imaging' class="offcanvas__section-link" >Imaging</a></li><li class="offcanvas__item hasChildren lastInLevel"><a href='/hst/instrumentation/stis/observing-strategies/available-modes' class="offcanvas__section-link" >Available Modes</a><button class="offcanvas__section-toggle" id="Available_Modes_39_control" type="button" aria-label="Available Modes submenu" aria-controls="Available_Modes_39_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Available_Modes_39_section" class="offcanvas__list" data-level="6" aria-labelledby="Available_Modes_39_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/stis/observing-strategies/available-modes/high-contrast-coronagraphy-at-small-inner-working-angles-with-bar5' class="offcanvas__section-link" >High Contrast Coronagraphy at Small Inner Working Angles with BAR5</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/stis/observing-strategies/available-modes/stis-bar5' class="offcanvas__section-link" >STIS BAR5</a></li></ul></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/stis/data-analysis-and-software-tools' class="offcanvas__section-link" >Data Analysis and Software Tools</a><button class="offcanvas__section-toggle" id="Data_Analysis_and_Software_Tools_40_control" type="button" aria-label="Data Analysis and Software Tools submenu" aria-controls="Data_Analysis_and_Software_Tools_40_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Data_Analysis_and_Software_Tools_40_section" class="offcanvas__list" data-level="5" aria-labelledby="Data_Analysis_and_Software_Tools_40_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/stis/data-analysis-and-software-tools/pixel-based-cti' class="offcanvas__section-link" >Pixel Based CTI</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/calibration' class="offcanvas__section-link" >Calibration</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/stis/documentation' class="offcanvas__section-link" >Documentation</a><button class="offcanvas__section-toggle" id="Documentation_41_control" type="button" aria-label="Documentation submenu" aria-controls="Documentation_41_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Documentation_41_section" class="offcanvas__list" data-level="5" aria-labelledby="Documentation_41_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/stis/documentation/instrument-science-reports' class="offcanvas__section-link" >Instrument Science Reports</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/stis/documentation/stsci-analysis-newsletter-stan' class="offcanvas__section-link" >STScI Analysis Newsletter (STAN)</a></li><li class="offcanvas__item noChildren"><a href='https://hst-docs.stsci.edu/stisihb' class="offcanvas__section-link" target='_blank' >STIS Instrument Handbook</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='https://hst-docs.stsci.edu/stisdhb' class="offcanvas__section-link" target='_blank' >STIS Data Handbook</a></li></ul></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/stis/flux-recalibration' class="offcanvas__section-link" >Flux Recalibration</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3' class="offcanvas__section-link" >Wide Field Camera 3</a><button class="offcanvas__section-toggle" id="Wide_Field_Camera_3_42_control" type="button" aria-label="Wide Field Camera 3 submenu" aria-controls="Wide_Field_Camera_3_42_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Wide_Field_Camera_3_42_section" class="offcanvas__list" data-level="4" aria-labelledby="Wide_Field_Camera_3_42_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/instrument-design' class="offcanvas__section-link" >Instrument Design</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/performance' class="offcanvas__section-link" >Performance</a><button class="offcanvas__section-toggle" id="Performance_43_control" type="button" aria-label="Performance submenu" aria-controls="Performance_43_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Performance_43_section" class="offcanvas__list" data-level="5" aria-labelledby="Performance_43_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/performance/usage-statistics' class="offcanvas__section-link" >Usage Statistics</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/performance/anomalies' class="offcanvas__section-link" >Anomalies</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/performance/cte' class="offcanvas__section-link" >CTE</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/performance/ground-testing' class="offcanvas__section-link" >Ground Testing</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/performance/monitoring' class="offcanvas__section-link" >Monitoring</a><button class="offcanvas__section-toggle" id="Monitoring_44_control" type="button" aria-label="Monitoring submenu" aria-controls="Monitoring_44_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Monitoring_44_section" class="offcanvas__list" data-level="6" aria-labelledby="Monitoring_44_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/wfc3/performance/monitoring/complete-anneal-history' class="offcanvas__section-link" >Complete Anneal History</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/performance/throughputs' class="offcanvas__section-link" >Throughputs</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/performance/cal-subsystem' class="offcanvas__section-link" >Cal Subsystem</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/proposing' class="offcanvas__section-link" >Proposing</a><button class="offcanvas__section-toggle" id="Proposing_45_control" type="button" aria-label="Proposing submenu" aria-controls="Proposing_45_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Proposing_45_section" class="offcanvas__list" data-level="5" aria-labelledby="Proposing_45_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/proposing/dithering-strategies' class="offcanvas__section-link" >Dithering Strategies</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/proposing/exception-reports' class="offcanvas__section-link" >Exception Reports</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/data-analysis' class="offcanvas__section-link" >Data Analysis</a><button class="offcanvas__section-toggle" id="Data_Analysis_46_control" type="button" aria-label="Data Analysis submenu" aria-controls="Data_Analysis_46_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Data_Analysis_46_section" class="offcanvas__list" data-level="5" aria-labelledby="Data_Analysis_46_control"><li class="offcanvas__item noChildren firstInLevel"><a href='https://github.com/spacetelescope/WFC3Library/tree/master/notebooks/filter_transformations' class="offcanvas__section-link" target='_blank' >Color Conversion Notebook</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/full-well-depth' class="offcanvas__section-link" >Full Well Depth</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources' class="offcanvas__section-link" >Grism Spectroscopy</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/data-analysis/ir-flats' class="offcanvas__section-link" >IR Flats</a><button class="offcanvas__section-toggle" id="IR_Flats_47_control" type="button" aria-label="IR Flats submenu" aria-controls="IR_Flats_47_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="IR_Flats_47_section" class="offcanvas__list" data-level="6" aria-labelledby="IR_Flats_47_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/ir-flats/blob-delta-flats-from-earth-flat-calibration-images' class="offcanvas__section-link" >Blob Delta-flats from Earth Flat Calibration Images</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/ir-persistence' class="offcanvas__section-link" >IR Persistence</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration' class="offcanvas__section-link" >Photometric Calibration</a><button class="offcanvas__section-toggle" id="Photometric_Calibration_48_control" type="button" aria-label="Photometric Calibration submenu" aria-controls="Photometric_Calibration_48_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Photometric_Calibration_48_section" class="offcanvas__list" data-level="6" aria-labelledby="Photometric_Calibration_48_control"><li class="offcanvas__item hasChildren firstInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-photometric-calibration' class="offcanvas__section-link" >UVIS Photometric Calibration</a><button class="offcanvas__section-toggle" id="UVIS_Photometric_Calibration_49_control" type="button" aria-label="UVIS Photometric Calibration submenu" aria-controls="UVIS_Photometric_Calibration_49_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="UVIS_Photometric_Calibration_49_section" class="offcanvas__list" data-level="7" aria-labelledby="UVIS_Photometric_Calibration_49_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-photometric-calibration/quad-filter-photometry' class="offcanvas__section-link" >Quad Filter Photometry</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-photometric-calibration/uv-filter-modified-keywords' class="offcanvas__section-link" >UV Filter Modified Keywords</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-photometric-calibration/previous-uvis-photometric-calibrations' class="offcanvas__section-link" >Previous UVIS Photometric Calibrations</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/uvis-encircled-energy' class="offcanvas__section-link" >UVIS Encircled Energy</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/ir-photometric-calibration' class="offcanvas__section-link" >IR Photometric Calibration</a><button class="offcanvas__section-toggle" id="IR_Photometric_Calibration_50_control" type="button" aria-label="IR Photometric Calibration submenu" aria-controls="IR_Photometric_Calibration_50_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="IR_Photometric_Calibration_50_section" class="offcanvas__list" data-level="7" aria-labelledby="IR_Photometric_Calibration_50_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/ir-photometric-calibration/previous-ir-photometric-calibrations' class="offcanvas__section-link" >Previous IR Photometric Calibrations</a></li></ul></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/photometric-calibration/ir-encircled-energy' class="offcanvas__section-link" >IR Encircled Energy</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/pixel-area-maps' class="offcanvas__section-link" >Pixel Area Maps</a></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/data-analysis/psf' class="offcanvas__section-link" >PSF</a><button class="offcanvas__section-toggle" id="PSF_51_control" type="button" aria-label="PSF submenu" aria-controls="PSF_51_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="PSF_51_section" class="offcanvas__list" data-level="6" aria-labelledby="PSF_51_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/psf/psf-search' class="offcanvas__section-link" >PSF Search</a></li></ul></li><li class="offcanvas__item noChildren"><a href='http://archive.stsci.edu/hst/index.html' class="offcanvas__section-link" target='_blank' >Retrieving Data</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/should-i-recalibrate' class="offcanvas__section-link" >Should I Recalibrate?</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/data-analysis/uvis-flats' class="offcanvas__section-link" >UVIS Flats</a></li><li class="offcanvas__item noChildren"><a href='/hst/observing/post-observation' class="offcanvas__section-link" >Post-Observation</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/data-analysis/uvis-and-ir-distortion-calibration' class="offcanvas__section-link" >UVIS and IR Distortion Calibration</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/calibration-plan' class="offcanvas__section-link" >Calibration Plan</a><button class="offcanvas__section-toggle" id="Calibration_Plan_52_control" type="button" aria-label="Calibration Plan submenu" aria-controls="Calibration_Plan_52_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Calibration_Plan_52_section" class="offcanvas__list" data-level="5" aria-labelledby="Calibration_Plan_52_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/calibration-plan/tv3-results' class="offcanvas__section-link" >TV3 Results</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/calibration-plan/tv2-results' class="offcanvas__section-link" >TV2 Results</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/calibration-plan/tv1-results' class="offcanvas__section-link" >TV1 Results</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/calibration-plan/old-versions' class="offcanvas__section-link" >Old Versions</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/software-tools' class="offcanvas__section-link" >Software Tools</a><button class="offcanvas__section-toggle" id="Software_Tools_53_control" type="button" aria-label="Software Tools submenu" aria-controls="Software_Tools_53_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Software_Tools_53_section" class="offcanvas__list" data-level="5" aria-labelledby="Software_Tools_53_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/wfc3/software-tools/crosstalk' class="offcanvas__section-link" >Crosstalk</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/software-tools/cte-tools' class="offcanvas__section-link" >CTE Tools</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/software-tools/exposure-time-calculators' class="offcanvas__section-link" >Exposure Time Calculators</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/software-tools/pipeline' class="offcanvas__section-link" >Pipeline</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/wfc3/documentation' class="offcanvas__section-link" >Documentation</a><button 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href='/hst/instrumentation/wfc3/documentation/grism-resources/wfc3-ir-grism-data-reduction-cookbook' class="offcanvas__section-link" >WFC3 IR Grism Data Reduction Cookbook</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/grism-frequently-asked-questions' class="offcanvas__section-link" >Grism Frequently Asked Questions</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/ir-grism-sky-images' class="offcanvas__section-link" >IR Grism Sky Images</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/wfc3-g141-calibrations' class="offcanvas__section-link" >WFC3 G141 Calibrations</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/wfc3-g280-calibrations' class="offcanvas__section-link" >WFC3 G280 Calibrations</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/wfc3-g102-calibrations' class="offcanvas__section-link" >WFC3 G102 Calibrations</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/documentation/grism-resources/uvis-grism-sky-images' class="offcanvas__section-link" >UVIS Grism Sky Images</a></li></ul></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/documentation/conference-posters' class="offcanvas__section-link" >Conference Posters</a></li></ul></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/wfc3/news' class="offcanvas__section-link" >News</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/focus-and-pointing' class="offcanvas__section-link" >Focus and Pointing</a><button class="offcanvas__section-toggle" id="Focus_and_Pointing_56_control" type="button" aria-label="Focus and Pointing submenu" aria-controls="Focus_and_Pointing_56_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Focus_and_Pointing_56_section" class="offcanvas__list" data-level="4" aria-labelledby="Focus_and_Pointing_56_control"><li class="offcanvas__item hasChildren firstInLevel"><a href='/hst/instrumentation/focus-and-pointing/focus' class="offcanvas__section-link" >Focus</a><button class="offcanvas__section-toggle" id="Focus_57_control" type="button" aria-label="Focus submenu" aria-controls="Focus_57_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Focus_57_section" class="offcanvas__list" data-level="5" aria-labelledby="Focus_57_control"><li class="offcanvas__item noChildren firstInLevel"><a href='/hst/instrumentation/focus-and-pointing/focus/secondary-mirror-moves' class="offcanvas__section-link" >Secondary Mirror Moves</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/focus-and-pointing/focus/hst-focus-model' class="offcanvas__section-link" >HST Focus Model</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/focus-and-pointing/focus/tiny-tim-hst-psf-modeling' class="offcanvas__section-link" >Tiny Tim HST PSF Modeling</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/focus-and-pointing/pointing' class="offcanvas__section-link" >Pointing</a><button class="offcanvas__section-toggle" id="Pointing_58_control" type="button" aria-label="Pointing 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href='/hst/instrumentation/focus-and-pointing/fov-geometry' class="offcanvas__section-link" >FoV Geometry</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/focus-and-pointing/documentation' class="offcanvas__section-link" >Documentation</a></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/instrumentation/legacy' class="offcanvas__section-link" >Legacy Instruments</a><button class="offcanvas__section-toggle" id="Legacy_Instruments_59_control" type="button" aria-label="Legacy Instruments submenu" aria-controls="Legacy_Instruments_59_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Legacy_Instruments_59_section" class="offcanvas__list" data-level="4" aria-labelledby="Legacy_Instruments_59_control"><li class="offcanvas__item hasChildren firstInLevel"><a href='/hst/instrumentation/legacy/nicmos' class="offcanvas__section-link" >NICMOS</a><button class="offcanvas__section-toggle" id="NICMOS_60_control" type="button" aria-label="NICMOS submenu" aria-controls="NICMOS_60_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="NICMOS_60_section" class="offcanvas__list" data-level="5" aria-labelledby="NICMOS_60_control"><li class="offcanvas__item noChildren firstInLevel lastInLevel"><a href='/hst/instrumentation/legacy/nicmos/instrument-science-reports-isrs' class="offcanvas__section-link" >Instrument Science Reports (ISRs)</a></li></ul></li><li class="offcanvas__item 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href='/hst/instrumentation/reference-data-for-calibration-and-tools' class="offcanvas__section-link" >Reference Data for Calibration and Tools</a><button class="offcanvas__section-toggle" id="Reference_Data_for_Calibration_and_Tools_62_control" type="button" aria-label="Reference Data for Calibration and Tools submenu" aria-controls="Reference_Data_for_Calibration_and_Tools_62_section" tabindex="-1" aria-expanded="false"><span class="svg-sprite -plus"><svg role="img" aria-label="open section"><use xlink:href="#plus"></use></svg></span><span class="svg-sprite -slider-dash"><svg role="img" aria-label="close section"><use xlink:href="#slider-dash"></use></svg></span></button><ul role="list" id="Reference_Data_for_Calibration_and_Tools_62_section" class="offcanvas__list" data-level="4" aria-labelledby="Reference_Data_for_Calibration_and_Tools_62_control"><li class="offcanvas__item noChildren firstInLevel"><a href='https://hst-crds.stsci.edu/' class="offcanvas__section-link" target='_blank' 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href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/bruzual-and-charlot-2003' class="offcanvas__section-link" >Bruzual and Charlot 2003</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/bruzual-persson-gunn-stryker-atlas-list' class="offcanvas__section-link" >Bruzual-Persson-Gunn-Stryker Atlas list</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/buser-kurucz-atlas' class="offcanvas__section-link" >Buser-Kurucz Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/calobs' class="offcanvas__section-link" >CALOBS</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/calspec' class="offcanvas__section-link" >CALSPEC</a></li><li class="offcanvas__item noChildren inPath selected"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/castelli-and-kurucz-atlas' class="offcanvas__section-link" aria-current='page'>Castelli and Kurucz Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/composite-qso-spectra-for-nir' class="offcanvas__section-link" >Composite QSO Spectra for NIR</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/the-galactic-emission-line-object-atlas' class="offcanvas__section-link" >The Galactic Emission Line Object Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/gunn-stryker-atlas-list' class="offcanvas__section-link" >Gunn-Stryker Atlas list</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/interstellar-extinction-curves' class="offcanvas__section-link" >Interstellar Extinction Curves</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/jacoby-hunter-christian-atlas' class="offcanvas__section-link" >Jacoby-Hunter-Christian Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/the-kinney-calzetti-spetral-atlas' class="offcanvas__section-link" >The Kinney-Calzetti Spectral Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/kinney-models' class="offcanvas__section-link" >Kinney Models</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/kurucz-1993-models' class="offcanvas__section-link" >Kurucz 1993 Models</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/non-stellar-spectra' class="offcanvas__section-link" >Non-Stellar Spectra</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/novae-models' class="offcanvas__section-link" >Novae Models</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/phoenix-models-available-in-synphot' class="offcanvas__section-link" >Phoenix Models available in Synphot</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/planetary-nebula-spectra' class="offcanvas__section-link" >Planetary Nebula Spectra</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/pickles-atlas' class="offcanvas__section-link" >Pickles Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/simple-stellar-population-atlas' class="offcanvas__section-link" >Simple Stellar Population Atlas</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/solar-system-objects-spectra' class="offcanvas__section-link" >Solar System Objects Spectra</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/swire-galaxies' class="offcanvas__section-link" >SWIRE Galaxies</a></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/the-trds-brown-atlas' class="offcanvas__section-link" >The TRDS Brown Atlas</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/astronomical-catalogs/trds-brown19-spectra-of-agns' class="offcanvas__section-link" >TRDS Brown19 Spectra of AGNs</a></li></ul></li><li class="offcanvas__item noChildren"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/modewave-data' class="offcanvas__section-link" >Modewave Data</a></li><li class="offcanvas__item noChildren lastInLevel"><a href='/hst/instrumentation/reference-data-for-calibration-and-tools/documentation' class="offcanvas__section-link" >Documentation</a></li></ul></li></ul></li><li class="offcanvas__item hasChildren"><a href='/hst/documentation' class="offcanvas__section-link" >Documentation</a><button class="offcanvas__section-toggle" 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</li> </ul> </div> </nav> </div><main id="main-content" > <section id="section-ba2af4ba-1ac6-42dc-8d13-1f82b19df3df" data-name="section-content" class="section-row none" > <h2 id="h2-sr-only-0ad1ec81-16ef-4916-8c6b-5eeab685788d" data-name="h2-sr-only-content" class="sr-only" data-include-in-navigation="false"> Content</h2> <div class="component-block container-fluid"> <p data-index="0">Access the <a href="https://archive.stsci.edu/hlsps/reference-atlases/cdbs/grid/ck04models/">CASTELLI-KURUCZ ATLAS</a></p> <h3 data-index="0" id="h3-CK-7a1403a5-4e84-4c96-a2e8-dbfbd6bc0ab0" data-name="h3-the-castelli-and-kurucz-2004-stellar-atmosphere-mo">The Castelli AND Kurucz 2004 Stellar Atmosphere Models</h3> <p>The atlas contains about 4300 stellar atmosphere models for a wide range of metal abundances, effective temperatures, and gravities. These LTE models with no convective overshooting computed by Fiorella Castelli, have improved opacities and abundances upon previously used by Kurucz (1990). The main improvements from previous opacity distribution functions listed in Castelli & Kurucz 2003 (IAU Symposium 210, Modelling of Stellar Atmospheres, Uppsala, Sweden, eds. N.E. Piskunov, W.W. Weiss. and D.F. Gray, 2003, ASP-S210) are:</p> <ol> <li>The replacement of the solar abundances from Andres & Grevesse (1989, GCA,53,197; AG89) with those from Grevesse & Sauval (1998 Space. Sci. Rev.,85,161; GS98). See Table 2 of Castelli & Kurucz 2004.</li> <li>The replacement of the TiO lines provided by Kurucz (1993) with the TiO lines from Schwenke (1998, Faraday Discuss., 109,321). Addition of the H<sub>2</sub> O lines (Partridge & Schwenke 1997, J. Chem. Phys., 106, 4618) and of the HI-HI and HI-H+ quasi-molecular absorptions near 1600 Å and 1400 Å (Allard et al. 1998, A&A, 335,1124), as distributed by Kurucz 1999a, 1999b. Extended molecular list and corrected previous bugs in Kurucz line lists.</li> </ol> <p>These models are computed with the same wavelength resolution and a smaller temperature resolution than the Kurucz 1993 models. All of the models have the same number of plane-parallel layers from <span class="math-tex">$log(\tau_{Ross})=-6.875$</span> to +2.00, in steps of <span class="math-tex">$\Delta[log(\tau_{Ross})] = 0.125$</span> computed assuming pure mixing-length convection (no overshooting) with 1/Hp=1.25. As before the microturbulent velocity used is <span class="math-tex">$22\ km \ s^{-1}$</span>.</p> <p>The ATLAS9 installed in TRDS is from "The Grids of ATLAS9-ODFNEW models and fluxes" from Fiorella Castelli's <a href="http://wwwuser.oats.inaf.it/castelli/grids.html" target="_blank">web page</a> created on January 2007. These grids are also available from <a href="http://kurucz.harvard.edu/grids.html" target="_blank">Dr. R. Kurucz's website</a>.</p> <p>The ATLAS9 includes models for abundances [M/H]=0.0, -0.5, -1.0, -1.5, -2.0, -2.5, +0.5, +0.2 and gravity range from <em>log g</em>= 0.0 to +5.0 in steps of +0.5. The range in effective temperature from 3500 K to 50000 K is covered with an uneven grid (see Table 1a). The model spectra cover the ultraviolet (1000 Å) to infrared (10 μm) spectral range with non-uniform wavelength spacing (see Table 1b).</p> <h4 data-index="0" id="h4-CK-407522cb-639d-4812-8dbf-da26945bc7bf" data-name="h4-table-1a-grid-of-temperatures-for-the-models" style="text-align: center;">Table 1a: Grid of Temperatures for the Models</h4> <table class="display sortable-table filterable-table simple-table" data-b-sort="false" data-columns="[null,null]" data-dom="l<"sortable-table__toolbar"<"container-fluid">f><"sortable-table__wrapper"rt>ip" data-module-dynamic="data-table" data-order="[]" data-searching="false" style="width:60%;"> <thead> <tr> <th data-datatable-hidden="false" data-datatable-sorting-direction="" data-datatable-sorting-order="" scope="col">Temperature Range (K)</th> <th data-datatable-hidden="false" data-datatable-sorting-direction="" data-datatable-sorting-order="" scope="col">Grid Step (K)</th> </tr> </thead> <tbody> <tr> <td>3000 - 13000</td> <td>250</td> </tr> <tr> <td>13000 - 50000</td> <td>1000</td> </tr> </tbody> </table> <p> </p> <h4 data-index="1" id="h4-CK-1ee48e15-d36d-49f0-8551-8d439c47a7ef" data-name="h4-table-1b-wavelength-coverage-for-the-models" style="text-align: center;">Table 1b: Wavelength Coverage for the Models</h4> <table class="display sortable-table filterable-table simple-table" data-b-sort="false" data-columns="[null,null]" data-dom="l<"sortable-table__toolbar"<"container-fluid">f><"sortable-table__wrapper"rt>ip" data-module-dynamic="data-table" data-order="[]" data-searching="false" style="width:60%;"> <thead> <tr> <th data-datatable-hidden="false" data-datatable-sorting-direction="" data-datatable-sorting-order="" scope="col" style="width: 431px;">Wavelength Range (microns)</th> <th data-datatable-hidden="false" data-datatable-sorting-direction="" data-datatable-sorting-order="" scope="col" style="width: 292px;">Grid Step (A)</th> </tr> </thead> <tbody> <tr> <td style="width: 431px;">0.10 - 0.29</td> <td style="width: 292px;">10</td> </tr> <tr> <td style="width: 431px;">0.29 - 1.00</td> <td style="width: 292px;">20</td> </tr> <tr> <td style="width: 431px;">1.00 - 1.60</td> <td style="width: 292px;">50</td> </tr> <tr> <td style="width: 431px;">1.60 - 3.20</td> <td style="width: 292px;">100</td> </tr> <tr> <td style="width: 431px;">3.20 - 8.35</td> <td style="width: 292px;">200</td> </tr> <tr> <td style="width: 431px;">8.35 - 10.0</td> <td style="width: 292px;">400</td> </tr> </tbody> </table> <h3 data-index="1" id="h3-1-495e6902-fb39-4e37-add9-3c868d296a34" data-name="h3-the-trds-version-of-the-atlas9"><br /> The TRDS version of the ATLAS9</h3> <p>The atlas is divided into 8 independent subdirectories, according to metal abundance. Within each subdirectory, the stellar atmosphere models are given in FITS table format. Each table consists of 12 different columns, the first contains the wavelength grid and the rest containing the spectrum of a star with the same effective temperature but different gravity, ranging from <em>log g</em>= 0.0 to +5.0. Columns filled with zeros indicate that the model spectrum for that particular metal abundance, effective temperature, and gravity combination is not covered by the atlas.</p> <div class="clearfix">The names of the table files are given as <em><strong>cksmh_ttttt.fits</strong></em>, where "<em>ck</em>", for Castelli & Kurucz, are the first two letters of the atlas; "<em>smh</em>" is the metal abundance of the model (<em>mh</em>) with its sign (<em>s</em>); and "<em>ttttt</em>" is the model's effective temperature, using four or five digits depending on the value. For example, a model with an effective temperature of 5000 K with [M/H]= -0.5 is indicated by <em>ttttt= 5000, s= m, mh= 05 </em>or<em> </em><em>ckm05_5000.fits. </em>Whereas a one with an effective temperature of<em> 5000K, </em>with [<em>M/H]= +3.5 </em>is indicated by <em>ttttt= 5000, s= p, mh= 35  </em>and have the name<em> </em><em>ckm05_5000.fits.</em></div> <p>Within each individual table file, each column is named "gyy", where "yy" corresponds to 10*<em>log g</em>. For example, <em>log g </em>= +0.5 and <em>log g </em>= +4.0 models are located in columns named g05 and g40, respectively. See the appendix for an example of a standard header of a table file.</p> <p>Physical fluxes of the spectra are given in FLAM surface flux units, i.e. <span class="math-tex">$ergs\ cm^{-2}\ s^{-1} A^{-1}$</span>. These flux units differ from those in the Castelli & Kurucz tables by a factor of <span class="math-tex">$3.336 * 10^{-19} * \lambda^{2}/4\pi$</span>, i.e. are converted from <span class="math-tex">$ergs\ cm^{-2} \ s^{-1}\ Hz^{-1} str^{-1}$</span> to <span class="math-tex">$ergs\ cm^{-2}\ s^{-1} {A} ^{-1}$</span>by multiplying the Castelli & Kurucz values by <span class="math-tex">$3.336 * 10^{-19} *\lambda^{2}/4\pi$</span>, where <span class="math-tex">$\lambda$</span> is in Angstroms. To convert to the observed flux at Earth, multiply by a factor of <span class="math-tex">$(R/D)^2$</span> where R is the stellar radius, and D is the distance to Earth.</p> <p>The names of the files located in each metal abundance subdirectory are listed in the README file located in each subdirectory. The range in gravity covered by the models for the different temperatures is also indicated.</p> <h3 data-index="2" id="h3-CK-b30951eb-89af-4a3b-af62-96a36921ad34" data-name="h3-use-with-pysynphot-or-astropy-synphot">Use with Pysynphot or Astropy Synphot</h3> <p><strong>Pysynphot</strong> or <strong>Astropy Synphot</strong> permits the selection of spectra within one of many columns in a single FITS table file using the "pysynphot. Icat ()" function. The syntax is "sp = pysynphot. Icat ('ck04models', t,m,g) where "t" is the effective temperature, "m" is the metal abundance [M/H], and "g" is the log gravity.</p> <p>Please note that the model spectra in the atlas are in surface flux units. Thus, if the number of counts or the calculated absolute flux is needed, the model spectrum must be renormalized appropriately. One can do this in <em><strong>pysynphot</strong></em> with the "sp.renorm()" function or the "sp.normalize()" function in <em><strong>Astropy <a href="https://synphot.readthedocs.io/en/latest/#id13">Synphot</a></strong></em><strong><em>.</em></strong></p> <p>A list of solar abundance stars of different spectral types and luminosity classes together with their closest Castelli & Kurucz 2004 model spectrum is presented in Table 2. The physical parameters <span class="math-tex">$T_{eff}$</span>, and log g, characterizing each of the O stars are taken from Martins, Schaerer, & Hiller's compilation of stellar parameters of Galactic O stars (Martins, Scharer & Hiller 2005, A&A,436,1049). The physical parameters for later stars are taken from Schmidt-Kaler's compilation of physical parameters of stars (Schmidt-Kaler 1982, Landolt-Bornstein VI/2b). For the later, the U-B and B-V colors of the closest model agree with the characteristic color of each star (see Schmidt-Kaler 1982) to better than 0.06 magnitude. For the cool end, K5I, M0I, and M2I stars, the physical parameters are taken from Leusque et al 2006, ApJ 645, 1102.</p> <p> </p> <h4 data-index="2" id="h4-CK-1824563d-c4c5-441f-8090-f4220d77f69d" data-name="h4-table-2-suggested-models-for-specific-stellar-type" style="text-align: center;">Table 2: Suggested Models for Specific Stellar Types</h4> <table class="display sortable-table filterable-table simple-table" data-b-sort="false" data-columns="[null,null,null,null]" data-dom="l<"sortable-table__toolbar"<"container-fluid">f><"sortable-table__wrapper"rt>ip" data-module-dynamic="data-table" data-order="[]" data-searching="false" style="width:60%;"> <thead> <tr> <th data-datatable-hidden="false" data-datatable-sorting-direction="" data-datatable-sorting-order="" scope="col">Type</th> <th data-datatable-hidden="false" data-datatable-sorting-direction="" data-datatable-sorting-order="" scope="col">T_{eff}</th> <th data-datatable-hidden="false" data-datatable-sorting-direction="" data-datatable-sorting-order="" scope="col">log_g</th> <th data-datatable-hidden="false" data-datatable-sorting-direction="" data-datatable-sorting-order="" scope="col">Kurucz model</th> </tr> </thead> <tbody> <tr> <td>O3V</td> <td>44852</td> <td>+3.92</td> <td>ckp00_45000[g45]</td> </tr> <tr> <td>O4V</td> <td>42857</td> <td>+3.92</td> <td>ckp00_43000[g45]</td> </tr> <tr> <td>O5V</td> <td>40862</td> <td>+3.92</td> <td>ckp00_41000[g45]</td> </tr> <tr> <td>O5.5V</td> <td>39865</td> <td>+3.92</td> <td>ckp00_40000[g40]</td> </tr> <tr> <td>O6V</td> <td>38867</td> <td>+3.92</td> <td>ckp00_39000[g40]</td> </tr> <tr> <td>O6.5V</td> <td>37870</td> <td>+3.92</td> <td>ckp00_38000[g40]</td> </tr> <tr> <td>O7V</td> <td>36872</td> <td>+3.92</td> <td>ckp00_37000[g40]</td> </tr> <tr> <td>O7.5V</td> <td>35874</td> <td>+3.92</td> <td>ckp00_36000[g40]</td> </tr> <tr> <td>O8V</td> <td>34877</td> <td>+3.92</td> <td>ckp00_35000[g40]</td> </tr> <tr> <td>O8.5V</td> <td>33879</td> <td>+3.92</td> <td>ckp00_34000[g40]</td> </tr> <tr> <td>O9V</td> <td>32882</td> <td>+3.92</td> <td>ckp00_33000[g40]</td> </tr> <tr> <td>O9.5V</td> <td>31884</td> <td>+3.92</td> <td>ckp00_32000[g40]</td> </tr> <tr> <td>B0V</td> <td>30000</td> <td>+3.90</td> <td>ckp00_30000[g40]</td> </tr> <tr> <td>B1V</td> <td>25400</td> <td>+3.90</td> <td>ckp00_25000[g40]</td> </tr> <tr> <td>B3V</td> <td>18700</td> <td>+3.94</td> <td>ckp00_19000[g40]</td> </tr> <tr> <td>B5V</td> <td>15400</td> <td>+4.04</td> <td>ckp00_15000[g40]</td> </tr> <tr> <td>B8V</td> <td>11900</td> <td>+4.04</td> <td>ckp00_12000[g40]</td> </tr> <tr> <td>A0V</td> <td>9520</td> <td>+4.14</td> <td>ckp00_9500[g40]</td> </tr> <tr> <td>A1V</td> <td>9230</td> <td>+4.10</td> <td>ckp00_9250[g40]</td> </tr> <tr> <td>A5V</td> <td>8200</td> <td>+4.29</td> <td>ckp00_8250[g40]</td> </tr> <tr> <td>F0V</td> <td>7200</td> <td>+4.34</td> <td>ckp00_7250[g40]</td> </tr> <tr> <td>F2V</td> <td>6890</td> <td>+4.34</td> <td>ckp00_7000[g40]</td> </tr> <tr> <td>F5V</td> <td>6440</td> <td>+4.34</td> <td>ckp00_6500[g40]</td> </tr> <tr> <td>F8V</td> <td>6200</td> <td>+4.40</td> <td>ckp00_6250[g45]</td> </tr> <tr> <td>G0V</td> <td>6030</td> <td>+4.39</td> <td>ckp00_6000[g45]</td> </tr> <tr> <td>G5V</td> <td>5770</td> <td>+4.49</td> <td>ckp00_5750[g45]</td> </tr> <tr> <td>G8V</td> <td>5570</td> <td>+4.50</td> <td>ckp00_5500[g45]</td> </tr> <tr> <td>K0V</td> <td>5250</td> <td>+4.49</td> <td>ckp00_5250[g45]</td> </tr> <tr> <td>K2V</td> <td>4780</td> <td>+4.5</td> <td>ckp00_4750[g45]</td> </tr> <tr> <td>K4V</td> <td>4560</td> <td>+4.5</td> <td>ckp00_4500[g45]</td> </tr> <tr> <td>K5V</td> <td>4350</td> <td>+4.54</td> <td>ckp00_4250[g45]</td> </tr> <tr> <td>K7V</td> <td>4060</td> <td>+4.5</td> <td>ckp00_4000[g45]</td> </tr> <tr> <td>M0V</td> <td>3850</td> <td>+4.59</td> <td>ckp00_3750[g45]</td> </tr> <tr> <td>M2V</td> <td>3580</td> <td>+4.64</td> <td>ckp00_3500[g45]</td> </tr> <tr> <td>M5V</td> <td>3240</td> <td>+4.94</td> <td>ckp00_3500[g50]</td> </tr> <tr> <td>B0III</td> <td>29000</td> <td>+3.34</td> <td>ckp00_29000[g35]</td> </tr> <tr> <td>B5III</td> <td>15000</td> <td>+3.49</td> <td>ckp00_15000[g35]</td> </tr> <tr> <td>G0III</td> <td>5850</td> <td>+2.94</td> <td>ckp00_5750[g30]</td> </tr> <tr> <td>G5III</td> <td>5150</td> <td>+2.54</td> <td>ckp00_5250[g25]</td> </tr> <tr> <td>K0III</td> <td>4750</td> <td>+2.14</td> <td>ckp00_4750[g20]</td> </tr> <tr> <td>K5III</td> <td>3950</td> <td>+1.74</td> <td>ckp00_4000[g15]</td> </tr> <tr> <td>M0III</td> <td>3800</td> <td>+1.34</td> <td>ckp00_3750[g15]</td> </tr> <tr> <td>O5I</td> <td>40300</td> <td>+3.34</td> <td>ckp00_40000[g45]</td> </tr> <tr> <td>O6I</td> <td>39000</td> <td>+3.24</td> <td>ckp00_39000[g40]</td> </tr> <tr> <td>O8I</td> <td>34200</td> <td>+3.24</td> <td>ckp00_34000[g40]</td> </tr> <tr> <td>B0I</td> <td>26000</td> <td>+2.84</td> <td>ckp00_26000[g30]</td> </tr> <tr> <td>B5I</td> <td>13600</td> <td>+2.44</td> <td>ckp00_14000[g25]</td> </tr> <tr> <td>A0I</td> <td>9730</td> <td>+2.14</td> <td>ckp00_9750[g20]</td> </tr> <tr> <td>A5I</td> <td>8510</td> <td>+2.04</td> <td>ckp00_8500[g20]</td> </tr> <tr> <td>F0I</td> <td>7700</td> <td>+1.74</td> <td>ckp00_7750[g20]</td> </tr> <tr> <td>F5I</td> <td>6900</td> <td>+1.44</td> <td>ckp00_7000[g15]</td> </tr> <tr> <td>G0I</td> <td>5550</td> <td>+1.34</td> <td>ckp00_5500[g15]</td> </tr> <tr> <td>G5I</td> <td>4850</td> <td>+1.14</td> <td>ckp00_4750[g10]</td> </tr> <tr> <td>K0I</td> <td>4420</td> <td>+0.94</td> <td>ckp00_4500[g10]</td> </tr> <tr> <td>K5I</td> <td>3850</td> <td>+0.34</td> <td>ckp00_3750[g05]</td> </tr> <tr> <td>M0I</td> <td>3650</td> <td>+0.14</td> <td>ckp00_3750[g00]</td> </tr> <tr> <td>M2I</td> <td>3450</td> <td>-0.06</td> <td>ckp00_3500[g00]</td> </tr> </tbody> </table> <h3 data-index="3" id="h3-CK-e3c35cec-7b55-4bcf-81ff-c246ba032d8e" data-name="h3-"> </h3> <h4 data-index="4" id="h3-CK-2ac96942-8ede-4a5c-99ab-cc05585d56f7" data-name="h3-appendix">Appendix</h4> <p>Below is an example of a standard header for the table files in the CDBS version of Castelli & Kurucz 2004 atlas. In this example, the name of the file is ckp00_8000.fits and contains all the models for a star of metallicity <em>log Z</em>= 0.0 and effective temperature <span class="math-tex">$T_{eff}$</span>= 8000 K. Models cover a range of gravities from l<em>og g</em> = +1.0 (g10 in the header) to <em>log g </em>= +5.0 (g50 in the header). Models for gravities <em>log g </em>= +0.0 and +0.5 are not available for this particular metallicity and effective temperature combination, and therefore do not appear listed in the header. Their corresponding columns (g00 and g05) are filled with zeros. The models are in FLAM surface flux units, i.e.<span aria-label="math widget" role="region" tabindex="-1"> <span class="math-tex">$ergs \ cm^{-2} \ s^{-1} \ A^{-1}$</span></span></p> <h5 data-index="0" id="h5-CK-c269ed73-daa0-425b-8ee3-3a9b973ed8aa" data-name="h5-header-for-table-file-ckp00_8000fits">Header for table file ckp00_8000.fits</h5> <pre> 1 TEFF i 8000 2 LOG_Z d 0. <strong><u>This is actually metal abundance</u></strong> <strong><u>and not metallicity</u></strong> 3 HISTORY t File created by F.R.Boffi 4 HISTORY t ATLAS9 model atmospheres by Castelli and Kurucz (2004). 5 HISTORY t Wavelength is in Angstrom. 6 HISTORY t Fluxes tabulated in units of erg/s/cm^2/A 7 HISTORY t (after converting original units into "flam", 8 HISTORY t as described in README file and the SYNPHOT manual) 9 HISTORY t and are surface fluxes. To transform to observed 10 HISTORY t fluxes multiply by (R/D)^2 where R is the 11 HISTORY t radius of the star and D the distance. 12 HISTORY t Each column in the table represents the 13 HISTORY t spectrum of a star for the same metallicity 14 HISTORY t and effective temperature but different gravity. 15 HISTORY t Gravities range from log_g = +0.0 (g00 in the column 16 HISTORY t header) to log_g = +5.0 (g50 in the column header). </pre> <script>hljs.initHighlightingOnLoad();</script> </div></section><div class="credits dark-background-stsci-dark-blue"> <div class="container-fluid"> <div class="row"> <div class="col-xs-12"> <h2 id="h2-sr-only-pre-footer" class="sr-only">Pre-footer</h2> <div class="component-block container-fluid"> <div class="column-layout column-layout--with-dividers"> <div class="column-layout__column col-xs-12"> <div class="component-block container-fluid"> <h3 data-index="0" data-name="h4-please-contact-the-hst-help-desk-with-any-question" 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