MAGIC – Collaboration Meeting
June 12th, 2013 / Comments Off on MAGIC – Collaboration Meeting / by Vitaly
I am participating in MAGIC – Collaboration Meeting in Turku.
The paper “Steps towards a solution of the FS Aurigae puzzle. II. Confirmation of the intermediate polar status” has been accepted for publication in MNRAS
April 11th, 2013 / Comments Off on The paper “Steps towards a solution of the FS Aurigae puzzle. II. Confirmation of the intermediate polar status” has been accepted for publication in MNRAS / by Vitaly
The paper “Steps towards a solution of the FS Aurigae puzzle. II. Confirmation of the intermediate polar status” has been accepted for publication in Monthly Notices of the Royal Astronomical Society Main Journal (preprint).
Monitoring of SSS130101:122222-311525
March 12th, 2013 / Comments Off on Monitoring of SSS130101:122222-311525 / by Vitaly
Mar 21, 2013:
The object is wobbling around V=17.7. The variability is quite strong, and the period of primary modulation is nearly the same, ~110.6 min. However, recently a new, longer variability has appeared. It produced a relatively strong peak in the power spectrum. The period of this modulation is ~203.7 min.
Mar 12, 2013:
We have proceeded with time-resolved photometric observations. It seems the system has reached its quiescent level even though a quite strong night to night variability is observed. The modulation is still strong, but its behaviour is now more complex. Nevertheless, the period is nearly the same.
Mar 05, 2013:
The system is slowly fading: Vcur=17.50.
Feb 23, 2013:
The system is slowly fading: Vcur=17.18.
Feb 22, 2013:
The system is slowly fading: Vcur=17.10. (B-I)cur=1.2.
Feb 20, 2013:
The system is slowly fading: Vcur=16.89.
Feb 19, 2013:
The system is slowly fading: Vcur=16.79.
The modulation is very strong and non-sinusoidal, with amplitude of 0.4 mag. The current period of modulation determined between JD 2456337 and 2456344 is Pcur=110.56 min.
Feb 18, 2013:
The system is slowly fading: Vcur=16.68, (B-I)cur=1.04.
The modulation is very strong and non-sinusoidal, with amplitude of 0.4-0.5 mag.
Feb 17, 2013:
The system is slowly fading: Vcur=16.58, (B-I)cur=1.11.
The modulation is very strong and non-sinusoidal, with amplitude of 0.2-0.3 mag. The current period of modulation determined between JD 2456337 and 2456342 is Pcur=110.89 min.
Feb 16, 2013:
Vcur=16.38, (B-I)cur=1.10.
Feb 15, 2013:
The system has suddenly stopped fading! Vcur=16.09.
Feb 14, 2013:
The system is rapidly fading: Vcur=15.83, (B-I)cur=0.98.
Feb 13, 2013:
The system has begun a sharp decline: Vcur=14.48, (B-I)cur=0.29. Also, a double wave appeared in the light curve.
Feb 12, 2013:
The object is heading down but very slowly: Vcur=12.89+/-0.03, (B-I)cur=0.10
Feb 8, 2013:
The object is heading down but very slowly: Vcur=12.74+/-0.03, (B-I)cur=0.05
The period of modulation has shortened. The current period determined between JD 2456323 and 2456332 is Pcur=110.15 min.
The spectrum now is very different from what was observed by Tom Marsh (ATel#4704). All the Balmer lines except for Halpha and some HeI’s are in absorption with a weak emission core. Absorptions are red-shifted. It is interesting that HeII 4686 is rather strong and can be easily detected in emission. Halpha is in emission and double-peaked but is very weak, with the equivalent width of only ~2.6A.
Feb 1, 2013:
The object is still bright even though it is slowly declining: Vcur=12.49+/-0.03, (B-I)cur=-0.01
The current period of modulation Pcur=111.34 min.
Jan 31, 2013:
After a week of bad weather we took new data.
The object is still bright even though it is slowly declining: Vcur=12.45+/-0.03, (B-I)cur=-0.005
The current period of modulation Pcur=111.39 min.
Jan 23, 2013:
The object is still bright: Vcur=12.34+/-0.03, (B-I)cur=0.00
The current period of modulation Pcur=111.33 min.
Jan 22, 2013:
The object is still bright: Vcur=12.32+/-0.03, (B-I)cur=-0.004
The current period of modulation Pcur=120.73 min. However, today a strong 1-d alias appeared at 111.38 min.
Jan 20, 2013:
The object is still brightening and blueing: Vcur=12.24+/-0.03, (B-I)cur=-0.005
The current period of modulation Pcur=120.85 min.
Photometry of SSS130101:122222-311525
A meteor has exploded over Chelyabinsk, Russia.
February 15th, 2013 / Comments Off on A meteor has exploded over Chelyabinsk, Russia. / by Vitaly
A large meteor strike has been reported in Chalyabinsk on Friday morning at 05:20 GMT. Reports indicate major damage to buildings, including a roof collapse at a zinc factory, and at least 500 people injured, many from broken glass, as the shockwave blew out windows and rocked buildings. Asteroid 2012 DA14 (~45 m in diameter) will race past the Earth on Friday at a distance of just 27,700km – the closest ever predicted for an object of that size. However, indications from the Chelyabinsk meteor’s path suggest that the two events are entirely unrelated.
Re-brightening and photometric modulation of the optical transient SSS130101:122222-311525
January 18th, 2013 / 1 Comment » / by Vitaly
ATel #4744: Vitaly Neustroev (University of Oulu) and George Sjoberg (AAVSO):
We report a re-brightening and the consecutive detection of a photometric modulation of the recently discovered bright optical transient SSS130101:122222-311525 (Drake et al., ATel#4699).
This object has been in outburst since at least Dec 16, 2012 when it was found to be at V~11.8 (ATel#4700), some 7 mag brighter than it was previously. Subsequent photometry on Jan 1, 2013 showed the object still near maximum light at V = 12.3 +/- 0.1 (ATel#4699). However, the most recent reports indicated that SSS130101:122222-311525 had faded to magnitude 15.5 on Jan 4 and 16 on Jan 5 (vsnet-alert 15248).
Nevertheless, the data from our photometric monitoring indicate that after this decline a new increase in brightness has been observed during the last days. We performed time-resolved photometric observations of the object on Jan 10, 16 and 17 with the 0.35-m Celestron C14 robotic telescope, located at New Mexico Skies in Mayhill, New Mexico. We used an SBIG ST-10XME CCD camera with Johnson-Cousins BVRI Astrodon Photometric filters. On Jan 10, we obtained 10 images with an exposure time of 60 sec which gave an average magnitude of V=13.74+/-0.04. On Jan 16, we performed 2-hours of time-resolved observations with an exposure time of 30 sec. The average magnitude of these observations was V=12.48+/-0.03. On Jan 17, we obtained 2h 20min of multicolor BVRI photometry. Exposure times were 15 seconds for the VRI filters and 30 seconds for B. These observations gave the following magnitudes:
B=12.62+/-0.04, V=12.54+/-0.03, R=12.46+/-0.03, I=12.42+/-0.04
The observations from Jan 16 and 17 also revealed a photometric modulation with an amplitude of ~0.08 mag and a period of about 95 min or slightly longer. This period agrees with the estimates of Kuulkers et al. based on the spectroscopic observations (ATel#4716,#4704).
Kuulkers et al. proposed a WZ Sge-type dwarf nova classification for SSS130101:122222-311525. If this is correct then the object is expected to show a superhump signal during decline from superoutburst. We note, however, that even if the detected modulation is a superhump, the corresponding orbital period is still longer than WZ Sge stars usually have. This puts the WZ Sge classification of SSS130101:122222-311525 in doubt.
Photometry of SSS130101:122222-311525
Astronomy Day 2012
April 28th, 2012 / Comments Off on Astronomy Day 2012 / by Vitaly
Happy Astronomy Day to everyone!
The Golden Age of Cataclysmic Variables and Related Objects
September 21st, 2011 / Comments Off on The Golden Age of Cataclysmic Variables and Related Objects / by Vitaly
I participated in the workshop “The Golden Age of Cataclysmic Variables and Related Objects” (Palermo, Italy) and have given the talk “Optical and X-ray Variability of the Peculiar cataclysmic variable FS Aur with a Magnetic and Freely Precessing White Dwarf”.
IAU Symposium 282: From Interacting Binaries to Exoplanets
July 27th, 2011 / Comments Off on IAU Symposium 282: From Interacting Binaries to Exoplanets / by Vitaly
I’m just back from Slovakia where I have participated in IAU Symposium 282: “From Interacting Binaries to Exoplanets: Essential Modeling Tools“. Have given a short talk and presented a poster “Long-term variability and outburst activity of FS Aurigae: further evidence for a third body in the system”.
The end of monitoring of FS Aurigae
March 17th, 2011 / Comments Off on The end of monitoring of FS Aurigae / by Vitaly
Update: Apr 16, 2011: FS Aur is declining from an outburst.
Upon my request, during the 2010-2011 observing season, AAVSO observers have conducted continuous, nightly monitoring of the unique cataclysmic variable FS Aurigae to clearly define the start and end times of consecutive dwarf nova outbursts and measure their outburst properties. The campaign goals have been successfully met; we have observed 7 consecutive outbursts in great details. An active stage of the campaign is complete even though nightly monitoring of the star through the end of the observing season is encouraged. However, no new colour and/or time-resolved observations are needed anymore. Thank you very much to everyone who observed!
Monitoring of FS Aurigae
January 12th, 2011 / Comments Off on Monitoring of FS Aurigae / by Vitaly
Update: Mar 14, 2011: FS Aur is in a quiescent state.
Upon my request, AAVSO observers began continuous, nightly monitoring of the cataclysmic variable FS Aur during the current (2010-2011) observing season to clearly define the start and end times of several consecutive dwarf nova outbursts and measure their outburst properties. More information can be found from AAVSO Alert Notice 428. I will provide timely updates about the status of this work here. You can also check @fs_aur on Twitter for updates.