Near infrared observations of Nova V1721 Aql (Nova Aquilae 2008)
ATel #3955; W. P. Varricatt, T. Wold, T. Carroll and J. Ehle (Joint Astronomy Centre, Hilo, HI, USA)
on 7 Mar 2012; 23:35 UT
Distributed as an Instant Email Notice Novae
Credential Certification: Watson Varricatt (w.varricatt@jach.hawaii.edu)
Subjects: Infra-Red, Nova
The fast, luminous and highly extinguished nova V1721 Aql (Hounsell et al. 2011, A&A, 530, A81) was discovered in outburst in Sept. 2008 (Yamaoka et al. 2008, IAUC, 8989, 1). We carried out near-IR photometry of this object with the 3.8-m UKIRT and WFCAM, using the near-IR filters Z, Y, J, H and K (effective wavelengths: 0.8717, 1.0305, 1.2483, 1.6313 and 2.2010 microns respectively) on multiple epochs from July to Oct. 2011. We derive the coordinates (J2000) RA=19:06:28.609, Dec=+07:06:44.63. The observed epochs, filter names and the magnitudes estimated (in the UKIRT-WFCAM photometric system) are given in the table below.
There are at least two modes of variability observed in our data. The prominent one is the simultaneous rise and fall in the brightness in all bands, the variations decrease from 0.63 mags in Z to 0.4 mags in K. There is also variability seen over a shorter time, observed as a fading in Z and Y, which changes to a brightening in H and K. The last three rows in the table show the JHK magnitudes downloaded from the UKIDSS GPS DR6+ database (observed in 2007). A comparison of our 2011 data with the 2007 UKIDSS data shows that the infrared magnitudes of the system have returned to the pre-outburst levels. Our observations suggest that the variations may be periodic; more frequent monitoring over a longer time period is required to understand that.
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UTDATE |UT |Heliocentric|Filt.|mag. |error
yyyymmdd |hh:mm:ss |Julian Date
|2450000+
Current observations:
20110723 |11:48:05 |5765.996659 | Y |18.248 |0.041
20110723 |11:50:38 |5765.998430 | Y |18.230 |0.032
20110723 |11:56:22 |5766.002410 | H |15.304 |0.020
20110723 |11:57:36 |5766.003267 | H |15.298 |0.010
20110723 |12:00:29 |5766.005270 | K |14.428 |0.020
20110723 |12:01:48 |5766.006184 | K |14.452 |0.010
20110821 |10:19:24 |5794.934055 | Z |19.088 |0.053
20110821 |10:24:25 |5794.937539 | Y |17.719 |0.020
20110821 |10:29:26 |5794.941023 | J |16.229 |0.010
20110821 |10:34:22 |5794.944448 | H |14.937 |0.012
20110821 |10:35:40 |5794.945351 | H |14.913 |0.010
20110821 |10:38:35 |5794.947376 | K |14.051 |0.010
20110922 |08:23:48 |5826.851597 | Z |19.238 |0.074
20110922 |08:28:23 |5826.854779 | Y |18.014 |0.030
20110922 |08:33:04 |5826.858031 | J |16.475 |0.013
20110922 |08:38:04 |5826.861500 | H |15.130 |0.010
20110922 |08:40:59 |5826.863530 | K |14.268 |0.010
20110923 |07:07:42 |5827.798673 | Z |19.431 |0.044
20110923 |07:15:41 |5827.804217 | Y |18.032 |0.016
20110923 |07:23:42 |5827.809783 | J |16.468 |0.010
20110923 |07:31:57 |5827.815512 | H |15.140 |0.010
20110923 |07:36:37 |5827.818752 | K |14.260 |0.010
20110928 |08:22:26 |5832.850155 | Y |17.886 |0.150
20110928 |08:30:24 |5832.855687 | J |16.415 |0.037
20110928 |08:38:40 |5832.861428 | H |15.140 |0.087
20110928 |08:43:14 |5832.864599 | K |14.316 |0.040
20111001 |08:00:57 |5835.834986 | Z |19.326 |0.070
20111001 |08:08:53 |5835.840494 | Y |17.885 |0.025
20111001 |08:17:01 |5835.846142 | J |16.392 |0.012
20111001 |08:25:30 |5835.852033 | H |15.050 |0.010
20111001 |08:30:24 |5835.855435 | K |14.174 |0.010
20111028 |05:49:30 |5862.741384 | Z |19.720 |0.078
20111028 |05:57:25 |5862.746881 | Y |18.281 |0.031
20111028 |06:05:22 |5862.752401 | J |16.705 |0.013
20111028 |06:13:36 |5862.758118 | H |15.375 |0.010
20111028 |06:18:11 |5862.761301 | K |14.449 |0.010
UKIDSS data:
20070830 |09:53:31.5 |4342.915565 | J |16.401 |0.012
20070830 |10:01:17.2 |4342.920955 | H |15.059 |0.007
20070830 |10:08:22.2 |4342.925874 | K |14.240 |0.009
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The data reduction and distribution are performed by the CASU and WFAU respectively.
