Optical Photometric Sequence near SN 2001el (NGC 1448)
Star RA (2000) DEC V B-V V-R V-I
SN 3:44:30.6 -44:38:24
1(a) 3:44:37.7 -44:39:34 12.736 (0.002) 0.621 (0.003) 0.372 (0.002) 0.747 (0.004)
1(b) 12.739 (0.003) 0.623 (0.006) 0.367 (0.002) 0.738 (0.002)
2(a) 3:44:30.4 -44:40:36 15.377 (0.002) 1.086 (0.009) 0.666 (0.003) 1.221 (0.005)
5(a) 3:44:21.8 -44:38:38 15.913 (0.002) 0.965 (0.010) 0.532 (0.004) 0.986 (0.005)
6(a) 3:44:26.3 -44:38:40 15.756 (0.002) 1.132 (0.013) 0.675 (0.006) 1.236 (0.004)
7(a) 3:44:29.5 -44:37:29 14.524 (0.002) 0.836 (0.005) 0.487 (0.002) 0.932 (0.005)
Notes: (a) Based on 5 nights of CCD photometry with YALO.
(b) The second set of values is based on 7 nights of single-channel
photoelectric photometry by Landolt, who also obtained U-B =+0.049 +/- 0.012 for this star.
Here is our UBVRIJHK light curve of SN 2001el. Note that the time of maximum
in the I, J, H, and K bands is roughly 4 days before the time of B-band maximum.
A full paper on this supernova was submitted to the Astronomical Journal
on 9 August 2002. The revised version is presently (Oct 7) in the hands of the
referee.
Below are the optical and infrared light curves of the Type Ia supernova 1999ee. The
X-band (1.05 microns; also known as the Y-band) calibration is not complete and we
have more work to do on this object, but this is the first such 10-filter light curve
of a Type Ia supernova.
The finder charts for SNe 1999da, 1999dk, 1999gp, 2000bk, and 2000ce are part
of preprint astro-ph/0106088. To access this paper click
here.
Below is a 300 sec V-band image of NGC 6411 with SN 1999da
just to the right of the galaxy. This image was obtained by Kevin Krisciunas
on 9 July 1999 starting at 6:41:17 UT with the Univ. WA 30-inch reflector
at Manastash Ridge. At this time V = 16.46, B-V = 0.52. According to IAUC
7219, this supernova is subluminous compared to other Type Ia supernovae,
not unusual for one that occurs in an elliptical galaxy. However, while it
is asserted that this is an elliptical galaxy, Brian Skiff would classify it
as SA0- , meaning it's some kind of slightly boxy hybrid between an S0 galaxy
and an elliptical.
Here is a 200 sec V-band image of UGC 1087 with SN 1999dk
just north of the galaxy near the center of the 11 by 11 arcmin field.
It was obtained on 23 Aug 1999 UT at 11:28:46 UT with the MRO 30-inch
telescope in central WA. At this time V = 14.99, B-V = 0.08.
Here is a V-band image of UGC 1993 and SN 1999gp by Kevin
Krisciunas and Frank Deglman, using the APO 3.5-m telescope on 30 December
1999 at 01:36 UT. North is approximately up, east approximately to the left.
(Image is rotated 10 degrees counterclockwise.)
This image is 4.8 arcmin on a side. Note that the foreground star
just north of the galaxy core is NOT the supernova.
This is the photometric sequence for SN 1999gp, based on
data obtained with the APO 3.5-m. Realistic uncertainties are at least
+/- 0.02 mag or more. The coordinates are tied to the USNO A2.0 catalog
and were determined by Brian Skiff. Important note: a key Landolt (1992)
field observable at this time of year is PG023+051. Landolt gives
V-I = -0.534 +/- 0.122 for that star, but it was basically too faint in
I for him to observe well, as the error bar shows. I find V-I = -0.350 +/- 0.017
for this star, and Peter Stetson finds V-I = -0.346 +/- 0.018. Using the
wrong adopted V-I color for this star can lead to serious systematic errors
in the V-I colors of the SN 1999gp field.
Here is a 120 sec V-band exposures of SN 2000bk in NGC 4520 by
Kevin Krisciunas and Russet McMillan, using the APO 3.5-m telescope
on 24 April 2000
starting at 04:30:20 UT. It is 4.8 arcmin on a side. North is up,
east to the left. V = 17.29 +/- 0.02, B-V = 0.74 +/- 0.02.
The photometric sequence given below is based on the calibration of
five photometric nights.
Realistic minimum uncertainties of the magnitudes and colors are +/- 0.02.
Below is a 30 sec V-band exposure of SN 2000ce in UGC 4195 by
Armin Rest and Russet McMillan, using the APO 3.5-m telescope
on 11 May 2000 starting at 02:54:29 UT. V = 16.86, B-V = 0.78.
We have determined that B-band maximum occurred on May 4 +/- 1 UT.
Below is a 120 sec V-band exposure of SN 2000cx in NGC 524, obtained
by Chelsey Logan and Tanya Tavenner with the MRO 0.76-m telescope
near Ellensburg, WA. It was taken at 10:12 UT on July 19, 2000.
The V magnitude was approximately 14.00 +/- 0.04 and the B-V color
is +0.13 +/- 0.06. On Jul 20 at 10:19 UT we found V = 13.82 +/- 0.02, B-V
= 0.16 +/- 0.02. So this SN appears to have been discovered before
maximum. In IAU Circular 7463 (July 23, 2000) we see that a spectrum
taken on July 23 UT indicates that this is an overluminous 1991T-like
Type Ia supernova a few days before maximum. We give below a preliminary
photometric sequence. One should not trust the photometry to better
than +/- 0.02 mag.
Here is a 200 sec V-band image of SN 2001ay taken by Kevin Krisciunas with
the CTIO 60-inch telescope on 23 May 2001 at 03:32 UT. North is up, east to
the left. The SN had V = 17.53, B-V = 0.97.
The star to the right and down (SW) of the galaxy has V = 15.498, U-B = 0.698,
B-V = 0.970, V-R = 0.585, V-I = 1.051.
SN 2001ba in MCG-05-28-1 was discovered by R. Chassagne, Reunion Island, on
27 and 28 April 2001. Here is a 10 second V-band exposure on 18 May 2001 at
00:56 UT by Kevin Krisciunas, using the 100-inch DuPont telescope at Las
Campanas Observatory. The field is rotated 22 degrees counter-clockwise from north
up, east to the left. The SN is 19 arc east and 22 arcsec south of the
center of the galaxy, which means that it is the stellar object below
the center of the galaxy.
Here is a 60 sec V-band image of SN 2001bb taken by Kevin Krisciunas with
the CTIO 60-inch telescope on 23 May 2001 at 05:34 UT. North is up,
east to the left. The SN had approximately V = 17.81 +/- 0.04,
B-V = 1.31 +/- 0.12. This object is a good candidate for subsequent image
subtraction data reduction once template images are obtained at a future date.
The star to the right of the galaxy (i.e. the one noticeably outside the disk of
the galaxy's light) has V = 16.325, U-B = -0.073,
B-V = 0.419, V-R = 0.275, V-I = 0.581.
Here is a 60 sec V-band image of SN 2001bf taken by Kevin Krisciunas with
the CTIO 60-inch telescope on 23 May 2001 at 06:56 UT. North is up, east
to the left. The SN had V = 15.09, B-V = 0.23.
The star just north of the galaxy has V = 13.789, U-B = 0.363, B-V = 0.803,
V-R = 0.468, V-I = 0.885, while the star just south of the galaxy has
V = 15.836, U-B = 0.793, B-V = 0.990, V-R = 0.589, V-I = 1.086, and the
star to the right (west) of that star has V = 15.200, U-B = 0.287, B-V = 0.791,
V-R = 0.470, V-I = 0.897. 
Photometric Sequence near SN 1999da (NGC 6411)
Star RA (2000) DEC V +/- B-V +/- V-R +/- V-I +/-
2 17 35 25.9 +60 47 37 18.311 0.014 0.724 0.022 0.447 0.020 0.842 0.023
3 17 35 29.8 +60 47 24 17.861 0.015 0.808 0.016 0.463 0.011 0.852 0.009
4 17 35 48.9 +60 48 29 18.171 0.040 1.368 0.120 1.054 0.052 2.360 0.076
5 17 35 33.5 +60 50 25 16.904 0.018 1.392 0.015 0.824 0.018 1.590 0.022
6 17 35 23.8 +60 52 42 14.656 0.002 0.971 0.006 0.547 0.003 1.075 0.003
7 17 35 20.1 +60 50 09 15.121 0.007 0.773 0.004 0.454 0.008 0.838 0.010
The coordinates were derived by Brian Skiff from the USNO-A2.0 catalog.
Stars 2, 3, 5, and 7 were measured by Kevin Krisciunas with the Apache Point
Observatory 3.5-m telescope on a photometric night with sub-arcsec seeing.
Stars 4 and 6 were observed by Krisciunas with the Manastash Ridge Observatory
0.76-m telescope. Differential V-band photometry of star 5 vs. star 7 indicates
constancy to +/- 0.032 mag, while star 6 vs. star 7 indicates constancy to
+/- 0.040 mag. Star 3 vs. star 5 differential photometry is of lesser
quality (+/- 0.096 mag).
The BVRI light curve of SN 1999da is given below. 
Photometric Sequence near SN 1999dk (UGC 1087)
Star RA DEC V +/- B-V +/- V-R +/- V-I +/-
2 1:31:35.1 +14:14:00 13.555 0.009 0.705 0.016 0.389 0.020 0.747 0.021
3 1:31:43.5 +14:15:31 14.374 0.011 0.757 0.012 0.416 0.020 0.785 0.022
4 1:31:24.0 +14:18:31 17.207 0.008 0.628 0.017 0.332 0.032 0.665 0.046
5 1:31:24.5 +14:19:18 17.294 0.017 1.374 0.054 0.861 0.034 1.625 0.037
Differential photometry of star 2 vs. star 3 indicates Delta V constant
to +/- 0.009 mag, meaning that each is constant to that level;
for star 4 vs. 3 Delta V is constant to +/- 0.031 mag;
star 5 vs. star 2 photometry indicates that star 5 might be variable
with a range of 0.2 mag. Given its B-V color, that might not be surprising.
We have not used star 5 as one of the comparison stars for the 99dk reduction
on the two nights that it was "too faint" by 0.2 mag.
The BVRI light curve of SN 1999dk is given below. 
Photometric Sequence near SN 1999gp (UGC 1993)
Star RA (2000) DEC V +/- B-V +/- V-R +/- V-I +/-
SN 2 31 39.2 +39 22 52
2 2 31 37.5 +39 23 37 16.823 0.006 0.952 0.009 0.489 0.010 1.042 0.013
3 2 31 45.6 +39 22 46 17.410 0.004 0.655 0.007 0.328 0.009 0.778 0.004
4 2 31 40.6 +39 21 47 17.986 0.006 0.693 0.005 0.364 0.007 0.807 0.012
5 2 31 40.0 +39 21 14 17.265 0.006 0.595 0.016 0.332 0.008 0.776 0.009
6 2 31 37.4 +39 21 54 16.862 0.002 0.882 0.007 0.470 0.010 1.018 0.014
7 2 31 34.1 +39 21 31 18.309 0.009 1.242 0.005 0.711 0.011 1.456 0.010
8 2 31 33.0 +39 23 07 18.959 0.011 1.076 0.016 0.618 0.011 1.315 0.017
9 2 31 31.0 +39 24 06 15.821 0.010 0.569 0.006 0.313 0.012 0.758 0.011
10 2 31 39.0 +39 21 46 14.499 0.002 0.576 0.008 0.286 0.007 0.655 0.029
The V-I calibration was done adopting V-I = -0.350 for PG0231+051.
Here is the BVRI and near infrared light curve of SN 1999gp.
The data have been reduced using infrared and optical templates
of the galaxy obtained 284 and 325 days, respectively, after
the date of B-band maximum 
Photometric Sequence near SN 2000bk (NGC 4520)
Star RA (2000) DEC V +/- B-V +/- V-R +/- V-I +/-
1 12 33 55.29 -07 22 43.8 17.882 0.006 0.982 0.013 0.580 0.002 1.086 0.009
2 12 33 48.70 -07 23 36.9 16.462 0.002 0.510 0.009 0.348 0.004 0.690 0.014
3 12 33 53.75 -07 23 57.1 18.282 0.004 0.680 0.012 0.429 0.007 0.860 0.010
4 12 33 59.18 -07 23 11.5 16.192 0.004 0.456 0.007 0.295 0.002 0.582 0.011
5 12 34 00.71 -07 21 55.4 18.340 0.002 0.603 0.011 0.386 0.004 0.748 0.013
6 12 33 58.95 -07 21 38.3 18.095 0.005 0.695 0.014 0.442 0.003 0.854 0.014
7 12 33 56.71 -07 20 52.1 17.744 0.003 1.530 0.016 0.994 0.005 2.054 0.007
8 12 33 48.33 -07 22 35.2 15.000 0.005 0.602 0.012 0.365 0.005 0.719 0.012
Coordinates are with respect to USNO-A2.0, determined by Brian Skiff.
Here is the BVRI and near infrared light curve of SN 2000bk: 
Photometric Sequence near SN 2000ce (UGC 4195)
Star RA (2000) DEC V +/- B-V +/- V-R +/- V-I +/-
SN 8:05:09.5 +66:47:15
1 8:05:18.8 +66:47:06 15.725 0.002 0.813 0.005 0.448 0.013 0.870 0.007
2 8:05:07.6 +66:46:01 15.829 0.002 0.694 0.004 0.413 0.012 0.821 0.006
3 8:05:18.4 +66:45:12 16.815 0.003 0.838 0.022 0.461 0.015 0.893 0.01
4 8:05:18.8 +66:46:03 17.342 0.005 0.566 0.006 0.338 0.012 0.691 0.008
5 8:05:27.0 +66:46:37 16.043 0.003 1.123 0.005 0.641 0.010 1.192 0.007
6 8:05:14.6 +66 47:42 18.337 0.014 1.682 0.089 1.220 0.018 2.759 0.019
Here is the BVRI and near infrared light curve of SN 2000ce: 
Preliminary Photometric Sequence near SN 2000cx (NGC 524)
RA (2000) DEC V +/- B-V +/- V-R +/- V-I +/-
SN 1 24 46.15 +9 30 30.9
1 1 24 47.79 +9 30 01.5 11.145 0.005 0.528 0.011 0.325 0.014 0.672 0.010
2 1 24 52.68 +9 31 48.5 13.505 0.004 0.779 0.012 0.472 0.008 0.939 0.008
3 1 24 56.23 +9 30 19.0 12.568 0.004 0.591 0.008 0.371 0.011 0.754 0.010
4 1 24 42.79 +9 25 34.5 14.290 0.002 0.763 0.022 0.438 0.006 0.870 0.002
5 1 24 31.60 +9 30 22.7 13.729 0.010 0.753 0.056 0.425 0.005 0.843 0.004
6 1 23 49.75 +9 34 24.9 12.800 0.002 0.693 0.004 0.361 0.005 0.799 0.012
Coordinates of field stars were determined by Brian Skiff from GSC-ACT. Star 1
has the following near infrared magnitudes, derived from 5 nights of observations
on the LCO 1-m: Js = 10.006 (0.006), H = 9.758 (0.008), Ks = 9.689 (0.008).
From 4 nights of calibration we find that star 2 has: Js = 11.974 (0.006),
H = 11.585 (0.015), Ks = 11.501 (0.014).
Preliminary Photometry of SN 2000cx (with internal errors)
Julian Date V +/- B-V +/- V-R +/- V-I +/-
744.9248 14.008 0.007 0.169 0.015 0.011 0.009 -0.049 0.013
745.9299 13.814 0.005 0.161 0.011 0.026 0.006 -0.055 0.010
752.8828 13.281 0.002 0.163 0.006 -0.128 0.003 -0.438 0.007
753.9553 13.263 0.003 0.195 0.006 -0.126 0.003 -0.466 0.009
754.9664 13.265 0.002 0.222 0.005 -0.119 0.004 -0.492 0.007
757.9432 13.346 0.002 0.294 0.006 -0.152 0.003 -0.622 0.006
758.9351 13.380 0.003 0.315 0.006 -0.178 0.004 -0.659 0.007
759.9268 13.423 0.003 0.345 0.005 -0.726 0.007
760.9041 13.512 0.002 0.317 0.005 -0.245 0.002 -0.758 0.005
764.9112 13.803 0.003 0.359 0.006 -0.332 0.004 -0.788 0.008
765.9623 13.887 0.002 0.363 0.005 -0.332 0.004 -0.749 0.007
769.8777 14.142 0.003 0.484 0.006 -0.270 0.005 -0.477 0.007
776.9086 14.639 0.011 0.785 0.018 0.123 0.017 0.145 0.022
783.0008 15.140 0.012 0.954 0.025 0.320 0.020 0.412 0.032
784.9523 15.284 0.006 0.882 0.014 0.251 0.011 0.496 0.014
788.7088 15.473 0.003 0.863 0.007 0.259 0.007 0.392 0.007
807.8329 16.170 0.007 0.690 0.016 0.073 0.019 -0.039 0.017
822.7544 16.653 0.013 0.430 0.017 0.153 0.019 -0.187 0.025
834.6136 16.976 0.007 -0.323 0.016
The SN 2000cx data were derived from images obtained by Tanya Tavenner,
Chelsey Logan, Kevin Krisciunas, Melissa Thomas, Keely Snider, and Andrew
West.
