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S TUDY OF THE L OCAL C ORE -C OLLAPSE SN R ATE Kiranjyot (Jasmine) Gill, Dr. Michele Zanolin, Marek Szczepanczyk, Dr. Marica Branchesi, Dr. Giulia Stratta June 11 th, 2015 Urbino, Italy Embry-Riddle Aeronautical University; LIGO-Virgo; Universit degli Studi di Urbino
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Overview Initial focus: Galaxies within 20 Mpc convert absolute magnitude in blue luminosity (normalized to the Milky Way) and infer CCSNe rate Conversion between BLL and CCSNe rate is morphologically dependent (derived from observational data) Used: Gravitational Wave Galaxy catalog
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SNe Rate Plot (Bias corrections included) Rate + 1 sigma Rate - 1 sigma Our Estimated Rate @ 20 Mpc Soderberg et al. 2008 Estimated Rate @ 20 Mpc
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SN Surveys & Searches Within 50 Mpc: Not much change with rate of SNe detected = suggests completeness Courtesy of Cappellaro
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SN Surveys & Searches Courtesy of Cappellaro Within 20 Mpc: does not plateau = suggests incompleteness of SN surveys Number of Detections
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Completeness of SN Searches All Courtesy of Cappellaro
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Steps Followed to Estimate the Cumulative Rate of CCSNe Blue luminosity is a reasonable approximation for the star formation region mass. Where L B is the blue luminosity of each given galaxy, and M B is the absolute magnitude of each given galaxy. M milkyway used in the blue luminosity equation = -20.8 (Karachentsev et al. 2004, 2013). Estimate of the CCSNe rate for each galaxy: Galaxy_CCSNe_rate= L B/ L B_Milky_Way * MilkyWay_CCSNe_rate Cumulative sum of the CCSNe rate up to 20 Mpc
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MilkyWay_CCSNe_rate used in the Analysis Reference: Cappellaro et al. 1997, 1999 What is the Milky Way rate using this analysis 1.02 SNe/century Why rate of 1.02 ± 0.9 SNe/century? (Following Dragicevich et al. 1999 & Cappellaro et al. 1997, 1999) Based off of SNe Ib/c II rate for the spiral category (Milky Way luminosity 2.3 in units of 10 10 L B ) Comparison between our SNe rate and published measurements shows that they are consistent within each others uncertainties. Reference: van den Bergh et al. 1988
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Different Rates: Dragicevich et al. 1999 Different rates consistent within the large errors.
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Estimated SN Rate Within 20 Mpc using Dahlen et al. 2004 Redshift regions primarily concentrated in: 0.30 < z < 0.70 ~200 SNe/century Rate (Dahlen et al. 2004): 6E4 per Gpc 3 per year Reference: Dahlen et al. 2004, Cappellaro et al. 1999 1.Includes Type Sbc/Sd spirals 2.Randomized inclination of the disk of the galaxies =
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Luminosity Functions @ Various Distances Reference: White et al. 2011 20 Mpc 40 Mpc 100 Mpc
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Luminosity Distribution of the Galaxies within 20 Mpc 33 galaxies brighter than Milky Way and have a higher SNe rate 3225 galaxies that have a blue luminosity between 0 to 0.5 (dimmer than Milky Way & lower SNe rate) 64 galaxies that have a blue luminosity between 0.5 to 1 (dimmer than Milky Way & lower SNe rate)
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Classified and Unclassified Local Galaxies According to Morphology within 20 Mpc SPIRALS LENTICULARS ELLIPTICALS IRREGULARS VIRGO CLUSTER
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Morphological Classification Correction ( 2.6386e+03 ) / ( 2.6678e+03 ) = 0.9891 = 98.91% blue luminosity for classified galaxies ( 29.2680 ) / (2.6678e+03) = 0.0110 = 1.10% blue luminosity for unclassified galaxies Since fraction of blue luminosity taken by the unclassified galaxies = negligible within the catalog = neglect counting 1,686 galaxies for SN rate calculation
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Distribution of Local Galaxies within 20 Mpc Right Ascension (degrees) Declination (degrees) Number of Galaxies RA: 195° Dec: 28° # = 119 RA: 192° Dec: -41° # = 51 RA: 244° Dec: -61° # = 46 RA: 28° Dec: 36° # = 34 VIRGO CLUSTER
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