Filter Vegmag zp 4 --> 50 px aper correction Sirianni et al. corrections F625W 25.7220 0.222 +/- 0.007 0.169 (makes data fainter by 0.054) F775W 25.2541 0.229 0.007 0.173 ( " " " " 0.056) F850LP 24.2969 0.250 0.008 0.251 (can leave data unchanged)Note that the aperture corrections have the following arithmetic sense. If you got an F850LP instrumental magnitude of 23.250 from apphot in iraf, using a 4 px radius aperture and the zero points given above, then the F850LP magnitude on the Vega scale is 23.000.
The gain of the ACS wide field camera was 0.972 electrons per ADU and the readnoise was 4.85 electrons. I took the sky annulus from 20 to 30 px from the supernova and chose the mode of the values to give the sky value to use.
The zeropoint values on the web as of 8 October 2004 are 25.731, 25.256, and 24.326, respectively. You can see the latest values by clicking here . This means that to 0.009, 0.002, and 0.029 mag, respectively, needed to be added to the photometry. In the table below those extra corrections have been included.
HST Photometry (equivalent to 50 px radius Vega magnitudes)
These values encompass the Sirianni et al. aper corrections
for the F625W and F775W data.
(99 = missing data)
* JD F625W F775W F850LP
d033 2946.95 23.031 0.018 22.661 0.017 22.455 0.023
d033 2953.01 23.399 0.022 22.841 0.018 22.748 0.035
d033 2960.27 99 0.000 23.201 0.019 99 0.000
d033 2973.81 99 0.000 23.799 0.028 23.186 0.100
d033 2976.41 25.045 0.065 23.863 0.035 23.210 0.035
d033 2985.99 99 0.000 24.277 0.040 23.464 0.036
d033 3148.26 27.053 +0.51 26.908 +0.35 99 0.000
-0.35 -0.26
e147 2981.89 23.540 0.024 23.006 0.020 22.789 0.027
e147 2988.67 23.961 0.034 23.394 0.025 23.081 0.032
e147 2995.16 99 0.000 23.657 0.024 23.282 0.042
e147 3007.67 99 0.000 24.198 0.037 23.576 0.038
e147 3021.02 99 0.000 24.766 0.053 23.913 0.049
e315 2976.02 23.145 0.027 22.249 0.015 21.904 0.018
e315 2983.15 23.614 0.026 22.550 0.017 22.009 0.018
e315 2989.67 99 0.000 22.945 0.023 22.114 0.017
e315 3001.88 99 0.000 23.601 0.025 22.522 0.021
e315 3016.29 99 0.000 24.168 0.053 23.200 0.032
e510 2983.08 23.799 0.043 23.413 0.027 23.315 0.038
e510 2989.75 99 0.000 23.723 0.028 23.524 0.026
e510 3001.53 99 0.000 24.474 0.051 23.824 0.051
e510 3016.15 99 0.000 25.128 0.095 24.298 0.110
e531 2981.82 24.277 0.042 23.228 0.024 23.149 0.037
e531 2988.81 24.813 0.065 23.518 0.030 23.379 0.044
e531 2995.09 99 0.000 23.896 0.031 23.559 0.040
e531 3006.82 99 0.000 24.510 0.049 24.012 0.059
e531 3020.95 99 0.000 25.265 0.093 24.592 0.094
f011 3009.76 23.877 0.031 23.060 0.021 22.979 0.030
f011 3015.96 24.325 0.060 23.363 0.025 23.119 0.046
f011 3022.89 99 0.000 23.704 0.026 23.179 0.030
f011 3035.89 99 0.000 24.208 0.037 23.624 0.040
f011 3042.75 99 0.000 24.430 0.044 23.888 0.067
f041 3003.01 22.899 0.017 22.529 0.017 22.407 0.022
f041 3009.68 23.299 0.022 22.725 0.018 22.603 0.025
f041 3016.68 99 0.000 22.983 0.018 22.814 0.025
f041 3029.68 99 0.000 23.501 0.025 23.048 0.030
f041 3042.81 99 0.000 24.084 0.041 23.372 0.055
f216 3004.71 24.593 0.051 23.827 0.033 23.174 0.033
f216 3011.65 25.351 0.139 24.529 0.055 23.452 0.042
f216 3018.44 99 0.000 24.570 0.065 23.496 0.035
f216 3029.75 99 0.000 25.070 0.135 23.761 0.040
f216 3043.71 99 0.000 25.336 0.083 24.356 0.156
f244 3011.22 23.983 0.047 23.121 0.022 23.094 0.034
f244 3018.82 24.544 0.050 23.459 0.027 23.172 0.035
f244 3025.95 99 0.000 23.735 0.037 23.334 0.046
f244 3036.20 99 0.000 24.244 0.038 23.577 0.040
f244 3050.60 99 0.000 24.705 0.057 23.956 0.053
Here is the URL for the
Advanced Camera for Surveys . We next want to K-correct the F625W, F775W, and
F850LP magnitudes to rest frame U, B, and V. Click here for some fits to the HST data by Jose Luis Prieto, which are very encouraging. The fits include K-corrections to the rest frame B- and V-bands.
All the R-band natural system magnitudes (blue squares) and the HST F625W magnitudes (yellow dots) can be seen in the next figure. The uncertainties of the F625W points are actually smaller than the size of the points, so I have left off the error bars. The downward pointing blue triangles are 1-sigma upper limits in R. It is easily seen that e315 and f041 are the brightest at maximum. All graphs have a range of 80 days in X and 3.6 mag in Y.
And here is the corresponding plot for the I-band natural system magnitudes (green squares), the F775W data (orange dots), and the F850LP data (red triangles). The downward pointing triangles are 1-sigma upper limits in I. All graphs have a range of 100 days in X and 3.8 mag in Y.
Were the template images used for the ground-based photometry early enough? Here's a table of information relating to that issue. For some of the objects discovered in December 2003 (the fnnn's) I made templates from medians of sets of three images obtained at the start of the observing season. I use the JD's of B-band maximum from Adam's MLCS fits for all objects except e315 and e510. In those two cases I estimate it from the R-band observer frame photometry. "Dt" is the number of rest-frame days that the template was obtained with respect to rest-frame B or observer-frame R or I maximum.
Object Redshift Filter(s) Date of template(s) T(Bmax) Dt (days)
d033 0.53 R 11 Oct 2004 2934.93 +231.8
I 28 Nov 2002 -214.6
e147 0.64 R,I 19 Oct 2003 2962.80 -18.96
e315 0.79? R,I 19 Oct 2003 [2972.59] -23.18
0.41? -29.43
e510 0.68? R,I 20 Oct 2003 [2966.62] -20.30
e531 0.78 R,I 20 Oct 2003 2963.70 -17.75
f011 0.54 R,I 19,22,28 Oct 2003 2984.76 -28.67
f041 0.56 R,I 20, 28 Oct, 1 Nov 2985.90 -20.10
f216 0.60 R 19 Oct 2003 2979.79 -30.07
I 30 Oct 2003 -23.20
f244 0.54 R,I 29, 22, 28 Oct 2003 2986.11 -29.51
From the MLCS2k2 fits for these objects (which run to -20 days), at 18 days
prior to B-band maximum a Type Ia SN is 4.12 mag fainter (in B) than the peak. Thus,
for the subtractions we could have a systematic error as large as
0.024 mag error in the results (at maximum, and more when the SNe were
not at maximum). The sense is that our derived values are
"too faint" because there was some SN light in the templates. The times
of maximum are subject to some uncertainty, of course. Essence 1 (d033.waa6_10) was discovered on Oct 22, 2003. We obtained some HST templates on May 22, 2004, some 213 observer days (140 rest frame days) later. There appears to be some wisp of light at the location of the supernova in the template images in the F625W and F775W filter. This is most likely a marginal detection of the SN itself, in which case we should not just simply subtract these later images from the observations done in late 2003 to obtain photometry of the SN. We are likely still seeing the SN. There is no hint of the SN in the F850LP image of May 22nd.
Essence 6 = SN 2003kp = e147.
For essence 4 (SN 2003ku = e315) there is some controversy with the redshift of this object. SNID gives z = 0.79 as the most likely redshift, but 0.41 is the next best choice. To be on the safe side I used only the images of October 19th as the templates.
Essence 3 (e510) was faint and not well detected in the ground based R-band images. Only the first two R-band points are any good, from Nov 21 and 23 UT. However, the ground based I-band photometry makes a reasonably nice rest frame B-band light curve with the F775W data.
This object was not successfully observed spectroscopically. We were thwarted by fog in November of 2003, and the host was too faint to get a decent spectrum of when we tried in October of 2004. With no redshift that's why it was never announced in the IAU Circulars. So it has no official IAU designation. I used the October 20th images as templates. The I-band data peaks at JD 2452966.62. For a redshift of 0.68 this is 20.30 days after Oct 20th. But if the true redshift is greater than this, then the template is not quite early enough.
Essence 5 (SN 2003kv = e531) had a redshift of 0.78, and as we found with Essence 3 above, it gave a better signal-to-noise ratio in the ground based I-band images compared to R. This field itself does not have SDSS photometry, like Essence 9 below, so we determined the R and I mags of some nearby field stars using zeropoints derived from observations of the d087 field.
The HST photometry of ESSENCE 9 (SN 2003lh = f011) was done without image subtraction of the a set of HST images was obtained on June 8, 2004, some 101 rest frame days after the first set of frames obtained January 5th. There really isn't any obvious host galaxy there in the the later images, so I wouldn't know how to align the later images with the images taken when the SN was active.
I determined the photometric zeropoint(s) for f011 using a nearby field (e022) which did have SDSS photometry. I used 8 field stars observed on 6 photometric nights in R and 5 photometric nights in I.
Here is Essence 8 = SN 2003le = f041.
We obtained HST templates of the next one (f216) on 5 October 2004 UT. Note how this one seems to be such a fast riser and decliner. At the redshift of 0.596 the observed R-band photometry corresponds to a rest frame between the B-band and the U-band. U-band light curves are faster rising and declining than B-band light curves. But the observed I-band photometry would correspond to a rest frame between B and V.
Something is very odd about this object. How confident are we about the redshift? Looking again at the spectrum, the redshift does appear to be OK. If you have the hzteam web password at CfA, then check it out here . The spectroscopic observers wondered if this object might not be a Type Ia SN. But the spectrum does seem to have one of the silicon features.
As a sanity check for the photometry near f216 (Essence 7), I worked out I-band photmetry of three field stars near the SN. Based on 7 nights of observations between November 21 and December 19, I find the following results, consistent with constant brightness for these three stars:
RA DEC I 1-sigma scatter n
02:35:51.3 -08:05:18 19.005 (0.013) +/- 0.034 7
02:35:49.1 -08:05:30 20.347 (0.016) 0.043 7
02:35:49.3 -08:03:55 21.384 (0.023) 0.055 6
Here is Essence 10 (SN 2003li = f244).
The ground based photometry:
d033 = Essence 1
Natural system R-band mags:
2931.5122 22.634 (0.061)
2934.5039 22.634 (0.100)
2940.5266 22.755 (0.077)
+ -
2944.5066 23.031 0.197 0.166
2958.5242 23.774 0.272 0.217
2962.5244 24.143 0.518 0.351
2966.5344 24.066 0.569 0.373
2970.5720 24.463 0.405 0.296
2972.5415 24.295 0.283 0.225
2976.5334 24.485 0.900 0.486
2986.5295 > 24.814 1-sigma upper limit
Natural system I-band mags:
+ -
2931.5278 22.573 0.138 0.122
2934.5188 22.557 0.127 0.115
2940.5454 22.739 0.162 0.141
2958.5403 23.066 0.642 0.402 2.24-sigma
2966.5493 23.187 0.211 0.177 5.71-sigma
2970.5901 23.096 0.223 0.186 5.42-sigma
2972.5603 23.831 0.875 0.478 1.81-sigma
2976.5552 23.388 0.255 0.208 4.80-sigma
2986.5474 23.787 0.399 0.292 3.26-sigma
2990.5425 23.803 0.651 0.404 2.22-sigma
2994.5498 24.828 1.683 0.632 1.27-sigma
____________________________________________________
e147 = Essence 6
Natural system R-band mags:
2936.6482 > 24.904 1-sigma upper limit
2942.6521 24.090 (+0.258/-0.208)
2944.6162 23.838 (+0.349/-0.263)
2964.6660 22.669 0.055
2968.6602 23.198 (+0.558/-0.366) 2.49-sigma detection (clouds)
2970.6638 22.960 0.081
2970.6743 22.918 0.049
2972.6658 23.070 0.060
2974.6084 23.139 0.101
2976.6150 23.208 0.086
2988.6653 24.243 (+0.241/-0.197)
2992.6721 23.799 (+0.237/-0.194)
2996.6592 24.296 (+0.469/-0.327) 2.85-sigma detection
2998.6460 24.405 (+0.732/-0.434) 2.04-sigma detection
Natural system I-band mags:
2942.6753 24.207 (+1.18/-0.55) 1.51-sigma detection
2944.6306 23.425 0.201 0.170
2960.6848 22.413 0.308 0.241 4.06-sigma detection (clouds)
2964.6873 22.424 0.127 0.115
2968.6819 22.596 0.117 0.106 (less cloud effect than R image)
2970.6777 22.535 0.113 0.103
2972.6824 22.474 0.107 0.098
2974.6245 22.581 0.123 0.111
2976.6357 22.548 0.159 0.138
2988.6865 23.506 0.546 0.362 2.53-sigma detection
2992.6899 23.837 0.580 0.375 2.42-sigma detection
2996.6782 23.830 0.750 0.440 2.00-sigma detection
____________________________________________________
e315 = Essence 4
Natural system R-band mags:
2934.5557 > 24.872 1-sigma upper limit
2940.5710 > 24.927
2958.5754 23.058 0.144
2962.5793 22.939 0.090
2966.5864 22.436 0.057
2972.5833 22.566 0.067
2974.5334 22.582 0.043
2986.5820 23.259 0.071
2990.5652 23.548 0.155
2994.5674 23.939 0.142
3000.5774 24.145 0.168
Natural system I-band mags:
2934.5813 > 25.288 1-sigma upper limit
2940.6003 > 24.940 "
2958.5969 23.030 0.183
2962.6062 22.699 0.148
2966.6082 22.189 0.078
2972.6047 22.203 0.081
2974.5613 22.222 0.086
2986.6045 22.522 0.106
2990.5872 23.032 0.188
2994.5908 22.820 0.129
3000.5986 23.161 0.136
____________________________________________________
e510 = Essence 3
Natural system R-band mags:
2964.5205 24.141 (+0.419/-0.303) 3.12-sigma detection
2966.6145 23.812 0.237 0.196 5.08-sigma
2970.5320 24.504 1.072 0.529 1.59-sigma
2972.5249 24.265 0.437 0.311 3.01-sigma
2976.5234 24.432 0.978 0.507 1.68-sigma
2994.5361 24.635 1.404 0.593 1.38-sigma
2996.5442 > 25.364 1-sigma upper limit
Natural system I-band mags:
2942.5273 24.052 (+0.317/-0.246) 3.96-sigma detection
2960.5449 23.143 0.377 0.280 3.42-sigma
2964.5535 23.062 0.279 0.222 4.43-sigma
2966.6299 22.951 0.246 0.201 4.95-sigma
2970.6082 23.122 0.210 0.176 5.70-sigma
2972.5486 23.038 0.171 0.149 6.89-sigma
2976.5430 23.390 0.496 0.339 2.73-sigma
2988.5552 23.696 0.521 0.351 2.62-sigma
2994.5437 23.893 0.475 0.329 2.82-sigma
2996.5520 23.904 0.378 0.281 3.40-sigma
2998.5466 24.018 1.235 0.562 1.47-sigma
3000.5535 24.337 0.852 0.472 1.84-sigma
____________________________________________________
e531 = Essence 5
Natural system R-band mags:
2936.5901 > 23.802 1-sigma upper limit
+ -
2942.5935 24.596 0.456 0.319 2.92-sigma
2944.5620 24.411 1.476 0.604 1.35-sigma
2960.6130 23.361 0.137 0.122
2964.6172 23.473 0.170 0.147
2968.5623 23.632 0.351 0.265 3.62-sigma
2970.6157 23.477 0.156 0.137
2970.6841 23.729 0.155 0.136
2972.6108 23.888 0.296 0.231 4.20-sigma
2974.5671 23.818 0.152 0.133
2976.5679 23.747 0.231 0.191 5.21-sigma
2988.6169 24.027 0.250 0.204 4.85-sigma
2992.6431 25.105 1.409 0.593 1.38-sigma
2996.6140 24.352 0.481 0.332 2.79-sigma
2998.6040 24.533 0.737 0.434 2.03-sigma
3000.6047 24.613 0.412 0.299 3.16-sigma
Natural system I-band mags:
2942.6096 > 25.002 1-sigma upper limit
2944.5869 23.373 0.439 0.312 3.01-sigma
2964.6313 22.859 0.185 0.158
2968.5842 23.348 0.237 0.195
2970.6306 23.077 0.293 0.231 4.23-sigma
2972.6387 22.826 0.167 0.144
2974.5813 23.108 0.202 0.167
2976.5869 23.256 0.271 0.218 4.52-sigma
2988.6316 23.940 1.032 0.518 1.63-sigma
2996.6284 24.363 0.900 0.485 1.78-sigma
2998.6250 23.878 0.409 0.297 3.18-sigma
3000.6167 24.514 0.869 0.477 1.82-sigma
____________________________________________________
f011 = Essence 9
Natural system R-band mags:
2962.6165 > 25.540 0.0 1-sigma upper limit
2968.6123 23.816 (+0.261/-0.210)
2986.6145 22.535 0.074
2990.5967 22.710 0.060
2994.6008 22.751 0.067
2996.6250 23.003 0.104
2998.6213 22.900 0.083
3000.6128 23.172 0.083
Natural system I-band mags:
2962.6345 > 24.573 1-sigma upper limit
2968.6296 24.628 (+2.58/-0.701) 1.10-sigma detection
2986.6313 22.921 (+0.286/-0.227)
2990.6138 22.600 0.147
2994.6179 22.972 (+0.217/-0.180)
2996.6460 22.732 0.115
2998.6367 23.138 (+0.189/-0.162)
3000.6294 23.141 (+0.231/-0.190)
____________________________________________________
f041 = Essence 8
Natural system R-band mags:
2962.5833 23.805 (+0.284/-0.225)
2966.5750 23.786 (+0.308/-0.239)
2972.5801 22.984 0.083
2974.5300 22.802 0.069
2986.5713 22.456 0.059
2990.5547 22.548 0.074
2994.5564 22.490 0.052
2996.5724 22.576 0.086
2998.5635 22.587 0.053
3000.5703 22.717 0.058
Natural system I-band mags:
2966.5901 > 24.629 1-sigma upper limit
2972.5989 23.051 0.120
2974.5486 22.721 0.095
2986.5852 22.288 0.076
2990.5686 22.171 0.065
2994.5710 22.196 0.107
2996.5918 22.437 0.113
2998.5908 22.390 0.129
3000.5869 22.421 0.075
____________________________________________________
f216 = Essence 7
Natural system R-band mags:
JD R_nat +err -err
2964.6550 25.086 1.698 0.633 1.27-sigma detection
2968.6477 24.415 1.230 0.562 1.48-sigma
2972.6621 23.637 0.205 0.172
2974.6047 23.532 0.213 0.179
2976.6104 23.101 0.137 0.122
2988.6548 23.140 0.141 0.126
2992.6531 23.237 0.060 0.058
2996.6555 23.878 0.267 0.213
Natural system I-band mags:
2964.6697 > 24.903 1-sigma upper limit
2968.6638 > 23.118 " (clouds) not really useful
JD I_nat +err -err
2972.6765 24.093 0.594 0.381 2.37-sigma
2974.6189 22.473 +/- 0.080
2976.6292 22.585 +/- 0.129
2988.6687 23.604 0.814 0.460 1.90-sigma
2992.6777 24.053 0.753 0.441 2.00-sigma
____________________________________________________
f244 = Essence 10
Natural system R-band mags:
2958.6433 > 25.641 1-sigma upper limits
2962.6521 > 25.567
2966.6570 24.764 (+0.339/-0.258) (3.73-sigma detection)
2986.6497 22.750 0.058
2990.6311 22.693 0.067
2996.6519 23.076 0.109
2998.6426 23.145 0.088
Natural system I-band mags:
2958.6582 > 25.380 1-sigma upper limits
2962.6663 > 24.873
2966.6738 23.792 (+0.616/-0.390) (2.31-sigma detection)
2986.6641 22.494 0.080
2990.6453 22.756 0.109
2994.6411 22.668 0.090
2996.6663 22.878 0.091
2998.6531 22.777 0.114
____________________________________________________
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