MACHO Project Lightcurve Statistical Summary Tables

MACHO Project Lightcurve Statistical Summary Tables


Important Note (April 2009): These services are now deprecated and may be removed at any time.

All MACHO data is now available via IVOA compliant services located at http://macho.anu.edu.au

The new MACHO data services are fully compliant with current Virtual Observatory service standards, as specified by the IVOA. For full information on service standards, refer to the IVOA standards documentation.

For a brief description of the new services provided, see the user guide. For a brief description of how to perform some common data access tasks with them, see the how-to guide.


This page provides statistical summary data for all stars for which the MACHO project collected photometry.

Comprehensive summary statistics are provided for each star's complete lightcurve, for each MACHO field in the LMC, SMC and Galactic Bulge.

Refer here for MACHO field RA/Dec boundaries and field id numbers.

Data is delivered via ftp as one gzip-compressed ascii file per MACHO field.
Within each ascii file, each line contains data for a single star and each entry within the line is comma (',') delimited.
Each gzipped file is between 50MB and 110MB in size.


MACHO Lightcurve Statistical Summary Table Format

Col LabelDefinition
1 id MACHO star identification (field.tile.seq)
2 ra Right Ascension in J2000
3 dec Declination in J2000
4 npoints number of observations on the MACHO tile containing this star
5 rN red: number of good points on Lightcurve (LC)
6 rmagave red: median magnitude of LC in instrumental units
7 rerrave red: average error of measurements on LC in units of A, where A is the the measured flux divided by the median flux.
8 rsig red: sqrt of variance of A-1 measurements over LC.
9 rchi2w red: chi^2 per degree of freedom of fit to "constant flux" hypothesis weighted by flux errors
10 rqw red: probability of getting value as large as rchi2w by chance
11 rNr red: number of points on robustified LC
12 rerraver red: average error on robustified LC
13 rchi2r red: chi^2 per degree of freedom for robustified LC (variable star search)
14 rqr red: probability of getting value as large as rchi2r by chance
15 rs5 red: number of points on LC 5-sigma above median
16 rs5d red: number of points on LC 5-sigma below median (eclipsing binary search)
17 rmagaveu red: median magnitude in instrumental units before removing bad points
18 rdskyave red: average of red dsky sodophot measure
19 rdskysig red: sqrt of variance of red dsky sodophot measure
20 rpsfave red: average over LC of sodophot measure of goodness of psf fit
21 rpsfsig red: sqrt of variance of red psf sodophot measure
22 rcrdave red: average of crowding sodophot measure
23 rcosmave red: average of cosmic ray sodophot measure
24 rmissave red: average of missing pixel sodophot measure
25-44 b... blue: same as correspondingly named red quantity
45 bmrN number of points on the B-R LC [aka simultaneous R/B pts]
46 rbcross red/blue A-1   robustified measurements over LC cross correlation coefficient [Welch-Stetson; see AJ 105, 1813]
47 rauto red: A-1   robustified measurements over LC autocorrelation (lag=0) coefficient
48 bauto blue: A-1   robustified measurements over LC autocorrelation (lag=0) coefficient
49 filterN number of filters applied; always 3
50 filter[i].rfilmax red: max value of optimum filter for LC
51 filter[i].rfiltime red: LC time at which maximum occurred
52 filter[i].rNhi red: number points sigmathreshold high within duration of filter at peak (rfiltime)
50 filter[i].bfilmax blue: max value of optimum filter for LC
51 filter[i].bfiltime blue: LC time at which maximum occurred
52 filter[i].bNhi blue: number points sigmathreshold high within duration of filter at peak (bfiltime)
53-... filter[i+1].rfilmax red: repeat the 6 filter quantities until all filterN sets accounted.

Notes

  • Columns are comma separated.
  • A-1 is measured flux divided by median flux minus 1.
  • A robustified LC has 10 highest and 10 lowest values removed.
  • The filter array contains the time and significance of large bumps in the data on 3 different time scales. These bumps are used to find starting positions for LC fits. The filter characteristics follow:
    Filterdurationsigmathreshold
    1100 days1.3 sigma
    245 days1.5 sigma
    315 days2.0 sigma

    Summary tables for MACHO LMC fields, by field number:

    1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82

    Summary tables for MACHO SMC fields, by field number:

    206 207 208 211 212 213

    Summary tables for MACHO galactic Bulge fields, by field number:

    101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 301 302 303 304 305 306 307 308 309 310 311 401 402 403

    Acknowledgement to use when referencing MACHO Project data

    "This paper utilizes public domain data originally obtained by the MACHO Project, whose work was performed under the joint auspices of the U.S. Department of Energy, National Nuclear Security Administration by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48, the National Science Foundation through the Center for Particle Astrophysics of the University of California under cooperative agreement AST-8809616, and the Mount Stromlo and Siding Spring Observatory, part of the Australian National University."


    MACHO Project
    Research School of Astronomy and Astrophysics
    The Australian National University
    Canberra, ACT, 0200
    Australia

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