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Published byLenard Perkins Modified over 9 years ago
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ALFA Arecibo 305 m GALSPECT GALFA-HI is a 4′, large area, Galactic HI survey
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WNSHS/GAMES WALLABY/GASKAP EBHIS GALFA-HI compared to past, present, future surveys IGPS JEGP+ 11
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Arecibo Surveys ALFA SurveysOther instrument surveys PALFAEALFAGALFA ALFALFA ZOA AGESAUDS GALFA-HIGALFACTS GALFA-RRL TOGSTOGS2 I-GALFAPIs (some data taken contemporarily)
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GALFA-HI owes a lot of commensal observing!
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GALFA-HI DR1 is available to the public. DR2 soon! JEGP+ 11
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baseline ripple calibration x crossing- point gain calibration x first sidelobe calibration x
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baseline ripple calibration √ crossing- point gain calibration √ first sidelobe calibration √
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GALFA-HI matches IRAS and Planck resolutions Extinction HIFIR
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GALFA-HI matches IRAS and Planck resolutions Extinction HIFIR
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Interstellar morphologies: Cigars, Filaments, Needles Pancakes, Sheets Blobs Even Bicycle Wheels!
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GALFA FINDS HI BLOBS
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(Ap J, In press)
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Both small and weak!
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GALFA finds long, straight HI FILAMENTS!
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SHEETS are old hat. Consider this famous paper— the earliest known (to me) example of this geometry in the normal ISM…
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Here’s our Arecibo Millennium-survey friend 3C225b, showing prominent HI absorption. We measure the temperature (17 K); we use ISM pressure (4000 cm -3 K) to get volume density. N(HI) ~ 10 19 cm -2 n(HI) ~ 200 cm -3 N(HI)=n(HI) * L WHAT’S L????
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Arecibo (GALFA) map of the Knapp ultrathin sheet.
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Haud (2010) mapped the narrowest HI emission component: our cold thin cloud is part of a much larger structure, well-fit by an expanding ring! The whole structure is half in, half out of the Local Bubble… Our two ultrathin sheets
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A crude sketch of Haud’s rotating, expanding, translating “bicycle wheel in space”, looking down onto the Galaxy…
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