J/ApJ/867/108  Stellar masses and rest-frame u-g colors of SNIa  (Jones+, 2018)
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Should Type Ia supernova distances be corrected for their local environments?
    Jones D.O., Riess A.G., Scolnic D.M., Pan Y.-C., Johnson E., Coulter D.A.,
    Dettman K.G., Foley M.M., Foley R.J., Huber M.E., Jha S.W., Kilpatrick C.D.,
    Kirshner R.P., Rest A., Schultz A.S.B., Siebert M.R.
   <Astrophys. J., 867, 108 (2018)>
   =2018ApJ...867..108J
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ADC_Keywords: Supernovae; Stars, masses; Colors; Reddening; Optical
Keywords: cosmology: observations ; supernovae: general

Abstract:
    Recent analyses suggest that distance residuals measured from Type Ia
    supernovae (SNe Ia) are correlated with local host galaxy properties
    within a few kiloparsecs of the SN explosion. However, the
    well-established correlation with global host galaxy properties is
    nearly as significant, with a shift of 0.06mag across a low to high
    mass boundary (the mass step). Here, with 273 SNe Ia at z<0.1, we
    investigate whether the stellar masses and rest-frame u-g colors of
    regions within 1.5kpc of the SN Ia explosion site are significantly
    better correlated with SN distance measurements than global properties
    or properties measured at random locations in SN hosts. At >~2{sigma}
    significance, local properties tend to correlate with distance
    residuals better than properties at random locations, though despite
    using the largest low-z sample to date, we cannot definitively prove
    that a local correlation is more significant than a random
    correlation. Our data hint that SNe observed by surveys that do not
    target a pre-selected set of galaxies may have a larger local mass
    step than SNe from surveys that do, an increase of 0.071+/-0.036mag
    (2.0{sigma}). We find a 3{sigma} local mass step after global mass
    correction, evidence that SNe Ia should be corrected for their local
    mass, but we note that this effect is insignificant in the targeted
    low-z sample. Only the local mass step remains significant at
    >2{sigma} after global mass correction, and we conservatively estimate
    a systematic shift in H0 measurements of -0.14km/s/Mpc with an
    additional uncertainty of 0.14km/s/Mpc, ~10% of the present
    uncertainty.

Description:
    For this analysis, we combine 216 z<0.1 SNe from the Pantheon
    compilation (Scolnic+ 2018ApJ...859..101S) with 178 SNe Ia from the
    Foundation first data release (DR1; Foley+ 2018MNRAS.475..193F).

    We measure host galaxy properties with photometry from the PS1 first
    data release (Chambers+ 2016, II/349) and the Sloan Digital Sky Survey
    Data Release 14 (SDSS DR14; Abolfathi+ 2018ApJS..235...42A).

    After all cuts, grizy images for measuring the local mass step are
    available for 273 SNe Ia. Of these SNe, 195 lie in the SDSS footprint
    and therefore have u measurements for measuring the rest-frame u-g color.

File Summary:
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 FileName      Lrecl  Records   Explanations
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ReadMe            80        .   This file
localsn.dat      343      273   Measurements of Hubble residuals and host galaxy
                                 properties for 273 Type Ia supernovae at z<0.1
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See also:
 V/147  : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
 I/337  : Gaia DR1 (Gaia Collaboration, 2016)
 II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)
 II/358 : SkyMapper Southern Sky Survey. DR1.1 (Wolf+, 2018)
 J/AJ/131/527    : UBVRI light curves of 44 type Ia supernovae (Jha+, 2006)
 J/ApJ/700/331   : Light curves of type Ia supernovae (CfA3) (Hicken+, 2009)
 J/ApJ/700/1097  : Light curve parameters of SN Ia (Hicken+, 2009)
 J/ApJ/690/1236  : COSMOS photometric redshift catalog (Ilbert+, 2009)
 J/ApJS/185/32   : First-year SDSS-II SN results (Kessler+, 2009)
 J/AJ/139/519    : Carnegie supernova project. SNe Ia (Contreras+, 2010)
 J/AJ/139/120    : Low-redshift Type-Ia supernovae (Folatelli+, 2010)
 J/A+A/523/A7    : Light curves of type Ia supernovae in SNLS (Guy+, 2010)
 J/ApJ/722/566   : Host galaxies of SNeIa in SDSS-II SN survey (Lampeitl+, 2010)
 J/MNRAS/406/782 : Type Ia supernovae luminosities (Sullivan+, 2010)
 J/AJ/142/156    : The CSP (DR2): photometry of SNe Ia (Stritzinger+, 2011)
 J/ApJS/200/12   : CfA4: light curves for 94 type Ia SNe (Hicken+, 2012)
 J/A+A/568/A22   : Joint analysis of the SDSS-II & SNLS SNe Ia (Betoule+, 2014)
 J/MNRAS/438/1391  : Host galaxies of Type Ia SN from PTF (Pan+, 2014)
 J/ApJ/795/44    : PS1 SNe Ia (0.02<z<0.7) griz light curves (Rest+, 2014)
 J/AJ/148/13     : Redshifts of 65 CANDELS supernovae (Rodney+, 2014)
 J/MNRAS/450/905 : New SNe in SDSS DR9 (Graur+, 2015)
 J/ApJ/812/31    : Local Star Formation effects on type Ia SNe (Jones+, 2015)
 J/ApJ/826/56    : HST/WFC3 obs. of Cepheids in SN Ia host gal. (Riess+, 2016)
 J/ApJ/848/56    : Relationships between SNe Ia & host galaxies (Uddin+, 2017)
 J/ApJ/857/51    : Measuring dark energy data with PS1 SNe. II. (Jones+, 2018)
 J/ApJ/854/24    : Environmental dependence of SN Ia luminosities (Kim+, 2018)
 J/A+A/615/A68   : Type Ia supernova luminosities (Roman+, 2018)

Byte-by-byte Description of file: localsn.dat
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   Bytes Format Units        Label    Explanations
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   1- 11 A11    ---          SN       Supernova Identifier
  13- 14 I2     h            RAh      Hour of Right Ascension, Supernova (J2000)
  16- 17 I2     min          RAm      Minute of Right Ascension (J2000)
  19- 24 F6.3   s            RAs      Second of Right Ascension (J2000)
  26- 26 A1     ---          DE-      Sign of the Declination, Supernova (J2000)
  27- 28 I2     deg          DEd      Degree of Declination, Supernova (J2000)
  30- 31 I2     arcmin       DEm      Arcminute of Declination (J2000)
  33- 37 F5.2   arcsec       DEs      Arcsecond of Declination (J2000)
  39- 45 F7.5   ---          z        [0.01/0.1] Redshift
  47- 48 I2     h            RAHh     Hour of Right Ascension, Host Galaxy
                                       (J2000)
  50- 51 I2     min          RAHm     Minute of Right Ascension (J2000)
  53- 58 F6.3   s            RAHs     Second of Right Ascension (J2000)
  60- 60 A1     ---          DEH-     Sign of the Declination, Host Galaxy
                                       (J2000)
  61- 62 I2     deg          DEHd     Degree of Declination, Host Galaxy (J2000)
  64- 65 I2     arcmin       DEHm     Arcminute of Declination (J2000)
  67- 71 F5.2   arcsec       DEHs     Arcsecond of Declination (J2000)
  73- 77 F5.3   ---          Rpar     [0.07/5] Size- and orientation-weighted SN
                                       separation parameter (1)
  79- 82 F4.2   mag          E(B-V)   [0/0.2] Average galaxy reddening
  84- 90 F7.3   mag          (u-g)loc [0.1/2.2]?=-99 Local (u-g) color index (2)
  92- 98 F7.3   mag        b_(u-g)loc ?=-99 Lower bound on local (u-g) color (2)
 100-106 F7.3   mag        B_(u-g)loc ?=-99 Upper bound on local (u-g) color (2)
 108-114 F7.3   mag          (u-g)    [0.2/2.2]?=-99 Global (u-g) color
                                       index (2)
 116-122 F7.3   mag        b_(u-g)    ?=-99 Lower bound on (u-g) (2)
 124-130 F7.3   mag        B_(u-g)    ?=-99 Upper bound on (u-g) (2)
 132-137 F6.3   [Msun]       Massloc  [6.7/10.8] Local mass within a 3kpc radius
 139-144 F6.3   [Msun]     b_Massloc  Lower bound on local mass density
 146-151 F6.3   [Msun]     B_Massloc  Upper bound on local mass density
 153-158 F6.3   [Msun]       Mass     [6.7/12] Global mass
 160-165 F6.3   [Msun]     b_Mass     Lower bound on global mass density
 167-172 F6.3   [Msun]     B_Mass     Upper bound on global mass density
 174-180 F7.3   [kpc-2/yr]   SFRloc   [-42.5/-7.5]?=-99 local star formation
                                       rate, log(yr^-1^.kpc^-2^)
 182-188 F7.3   [kpc-2/yr] b_SFRloc   ?=-99 Lower bound SFRloc
 190-196 F7.3   [kpc-2/yr] B_SFRloc   ?=-99 Upper bound SFRloc
 198-204 F7.3   [kpc-2/yr]   SFR      [-42.5/-7.7]?=-99 Global star formation
                                       rate, log(yr^-1^.kpc^-2^)
 206-212 F7.3   [kpc-2/yr] b_SFR      ?=-99 Lower bound on SFR
 214-220 F7.3   [kpc-2/yr] B_SFR      ?=-99 Upper bound on SFR
 222-225 F4.1   deg          Inc      [12/70] Inclination
 227-232 F6.3   mag          Hres     [-0.5/0.4] Hubble residual, {mu}
 234-238 F5.3   mag        e_Hres     [0.04/0.3] Uncertainty in hubble-resid
 240-245 F6.3   mag          Hrescor  [-0.2/0.2] Bias correction, hubble-resid
 247-252 F6.3   ---          c        [-0.2/0.3] Tripp estimator parameter, c,
                                       light curve color parameter
 254-258 F5.3   ---        e_c        [0.009/0.1] Uncertainty in c
 260-265 F6.3   ---          ccor     [-0.11/0.04] Bias correction, c parameter
 267-272 F6.3   ---          x1       [-2.7/2.3] Tripp estimator, x1, light
                                       curve shape parameter
 274-278 F5.3   ---        e_x1       [0.02/0.9] Uncertainty in x1
 280-285 F6.3   ---          x1cor    [-0.4/1] Bias correction, x1 parameter
 287-292 F6.3   mag          mb       [14/20] Tripp estimator, mb, log of
                                       the light curve amplitude
 294-298 F5.3   mag        e_mb       [0.02/0.2] Uncertainty in mb
 300-305 F6.3   mag          mbcor    [-0.2/0.03] Bias correction, mb parameter
 307-314 F8.5   arcsec       r-A      [0.2/21] SExtractor galaxy ellipse
                                       parameter, A
 316-323 F8.5   arcsec       r-B      [0.1/11.2] SExtractor galaxy ellipse
                                       parameter, B
 325-330 F6.2   deg          theta    [-90/90] SExtractor galaxy ellipse
                                       parameter, {theta}
 332-343 A12    ---          Survey   Was the survey targeted or untargeted
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Note (1): The galaxy size- and orientation-weighted SN separation parameter, R
   (Sullivan+ 2006ApJ...648..868S) defined in Equation (2):
   R^2^=C_xx_x_r_^2^+C_yy_y_r_^2^+C_xy_x_r_yr_

   C_xx_=cos^2^({theta})/r^2^_A_+sin^2^({theta})/r^2^_B_

   c_xy_=2cos({theta})sin({theta})(1/r^2^_A_+1/r^2^_B_)

   C_yy_=sin^2^({theta})/r^2^_A_+cos^2^({theta})/r^2^_B_

   where x_r_=x_SN_-x_gal_ and y_r_=y_SN_-y_gal_. r_A_, r_B_, and {theta} are
   galaxy ellipse parameters measured by SExtractor. Each R parameter
   corresponds to an elliptical radius about the host center. We consider the
   host ambiguous if the minimum R is greater than 5.

   See section 2.2 for further explanations.
Note (2): The (u-g) color is given as null when u photometry was not available.
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History:
    From electronic version of the journal

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(End)                     Prepared by [AAS], Emmanuelle Perret [CDS] 14-Oct-2019