(Outburst image by Peter Nelson)
V699 Oph rare? outburst
> Subject: [vsnet-outburst 5673] V669 Oph in outburst > > OPHV699 030622.2313 14.5 SXN OUTBURST > OPHV699 030622.2472 14.4 SXN OUTBURSTThis outburst needs attention. The 2000 January outburst faded rather rapidly [vsnet-alert 4013, 4033], as in a normal outburst of an SU UMa-type dwarf nova. The 1999 April outburst (reaching mv=13.9) looked like a superoutburst. The object is probably a fainter companion to a non-variable close normal star. The separation is likely less than 1 arcsec. The observation should be naturally done for the combined light. Accurate astrometry in outburst is also desired.
Regards, Taichi Kato VSNET Collaboration team
[vsnet-outburst 5712] V699 Oph brightens
V699 Oph has brightened.
OPHV699 030703.406 143 Stu.RASNZ
Regards, Rod Stubbings == This rebrightening may be the waited genuine superoutburst! Please resume your time-resolved photometry!! Excellent target!! Regards, Taichi Kato VSNET Collaboration team
V699 Oph: secure superoutburst of a new SU UMa-type dwarf nova!
Dear Colleagues,
Tom Krajci's most recent observation has confirmed the rebrightening reported by Rod Stubbings. The light curve now clearly displays 0.25-mag superhumps! This finally confirmed the long-suspected SU UMa-type nature of this dwarf nova!!
Owing to the limited coverage, we can't tell the exact superhump period, but the profile suggests that the period seems to be shorter than 2 hr. Further observations are most strongly encouraged!! This star is apparently the best target of opportunity!!
Regards, Taichi Kato VSNET Collaboration team
(Superhump profile of V699 Oph)
V699 Oph superoutburst: superhump period
Dear Colleagues,
Last night, a number of VSNET Collaboration members have succeeded in observing V699 Oph. The observers include Peter Nelson, Sano-san, Tom Krajci and the Kyoto team. From the available data, we have for the first time been able to determine the superhump period of V699 Oph to be 0.0703(1) d. The period is not particularly unusual for an SU UMa-type dwarf nova, but the observed number of outbursts may be slightly low for a dwarf nova at this period. With the current intensive observation, we will soon be able to determine the superhump period change. Further observations are encouraged.
Regards, Taichi Kato VSNET Collaboration team
The dwarf nova V699 Oph is in outburst as detailed below:
990412.816 <155 A.Pearce 990416.765 139 A.Pearce 990416.783 139 A.Pearce 990416.818 140 A.PearceThe magnitude estimates were based on the VSNET sequence and the position of the dwarf nova was as per the VSNET chart.
Regards Andrew Pearce(vsnet-alert 2878)
Proposed indentification of V699 Oph
Congratulations to Andrew Pearce for observing an outburst of this supposed non-existent dwarf nova. Andrew notes that the outburst is at the position shown on the vsnet chart of this variable.
A comparison of the POSS I and POSS II images of this region using the DSS shows an apparently slightly variable faint star near the vsnet position of this variable.
This star is USNO A2.0 0825-09347211, with magnitudes 19.4 blue and 18.7 red. It is one of the bluest objects in the field. I suggest that this is V699 Oph in quiescence.
The J2000 position from ASNO A2.0 is: 16h 25m 13.710s -04d 40' 48.08"Astrometry during the current outburst will confirm (or refute) this identification.
Regards, Bruce Sumner
V699 Oph discussion (Sumner and Henden) + seq.
Date: Fri, 23 Apr 1999 16:35:05 +1000 Subject: V699 Oph discussion Arne has provided an astrometric position: 16 25 14.75 -04 40 25.8 (J2000)The DSS shows a star about magnitude 16 at this position, and Nikolaus Vogt measured this star photometrically many years ago, at V=16.5 B-V=1.2. A range of 13.9-16.5 is very small for a dwarf nova. There is thus still something to be learned about this star. Maybe there is a red star extremely close to V699 Oph.
However Arne was not able to observe any close companion. He has commented "maybe next month after it has faded, I can look for a close companion. The images look ok -- I don't see anything hidden in the wings, but if for example there really is a red star right on top of V699 I might miss it".
I have obtained a sequence for this variable, based on Arne's field photometry obtained during the last two nights.
131 V699 OPHIUCHI (UG) Range: 13.9-<16.5V
Position: 16 25 14.75 -04 40 25.8 (J2000, from .dat file)
Magnitude: V=14.972 B-V=0.322 (from .dat file)
ID RA (2000) DEC X Y N V ERR B-V ERR
1 16 25 26.5 -04 39 44 176 42 2 11.878 0.120 0.601 0.031
2 16 25 35.2 -04 34 33 307 353 2 12.292 0.006 0.471 0.037
3 16 25 18.9 -04 44 43 63 -257 2 13.216 0.006 1.230 0.022
4 16 25 28.8 -04 40 24 211 2 2 13.413 0.006 0.797 0.030
5 16 25 09.1 -04 41 35 -83 -69 2 14.120 0.000 0.963 0.030
6 16 25 18.7 -04 41 56 60 -90 2 14.290 0.000 1.177 0.024
7 16 25 26.0 -04 43 09 169 -163 2 14.658 0.000 0.937 0.030
8 16 25 07.6 -04 39 49 -106 37 2 14.936 0.000 1.278 0.030
9 16 25 10.8 -04 40 31 -58 -5 2 15.170 0.006 0.826 0.037
10 16 25 12.4 -04 41 27 -34 -61 2 15.302 0.006 0.955 0.023
11 16 25 17.0 -04 39 03 34 83 2 15.621 0.000 0.809 0.021
12 16 25 13.1 -04 39 00 -23 86 2 15.736 0.008 0.859 0.023
13 16 24 58.8 -04 39 09 -237 77 2 16.187 0.019 0.962 0.006
14 16 25 12.0 -04 39 57 -41 29 2 16.684 0.011 0.794 0.015
15 16 25 14.9 -04 40 42 3 -16 2 17.392 0.026 1.385 0.057
x and y are arcsec offsets, positive to the north & east respectively
Bruce Sumner
23 April 1999
Previous brightening of V699 Oph
During my previous survey of dwarf novae fields, I noticed the prominent variability of V699 Oph, which was then thought to be a non-CV. The variable object in the field agrees with the present outbursting(?) object. Because of the lack of the photometric log of that period, the date of the brightening is uncertain, but was either in 1991 April or May.
Regards, Taichi Kato
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