Is AAVSO doing follow-up on EF Eri?

Hi,

I was not able to find topic or note mentioning current status of EF Eri. Is AAVSO collecting multiband of this outburst?

EF Eri is a known CV (WD+Low mass companion) with p~0.0563d. It is usual for such systems to do outbursts (or Mini Novas). In this case I can’t find note and the brightening has been going for some while so it would be unusual if it has gone unnoticed.

Best,
-Arttu Sainio

Hi Arttu,

EF Eri is one of the original polars (AM Her type systems), from back when they are recognized as a subclass of magnetic CVs almost 50 years ago. For 20 years, it was one of the brightest polars, until it went into a low state in early 1997 I think. Polars are known for high/low state behavior, but EF Eri was in a low state for about 25 years (except for a couple of brief episode of brightening, see ATel 1562), a clear record for the longest low state as far as I know.

Looking at the ASAS-SN light curves you posted, it seems to be doing something intesresting since its return to the high state - so follow-up observations are clearly warranted. (I do know some observations, including X-ray observations, were done in 2022, which some people are working on.)

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HI,
I have added EF Eri to my observing program.
Josch Hambsch (HMB)

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Thank you both.

I am planning on short ATel with final WISE -mission MIR photometry + ASAS-SN photometry. I will be e-mailing @koji.mukai if you want to participate. @hambsch your observing plan should also be mentioned if you want to described it in short.

My observing plan is to use my remote observatory ROAD (Remote Observatory Atacama Desert) in Chile for the observations. It houses an 16" Optimized Dall Kirkham (ODK) telescope from Orion Optics, UK with an QHY600M CMOS camera and photometric filters from Astrodon on an ASA (Astrosysteme Austria) DDM85 direct drive mount. I cycle several stars simultaneously due to the high speed of the mount. Photometry is submitted to the AAVSO database.

Hi Arttu,
I have started observing EF Eri in Clear filter as it is a Cataclysmic variable and doing 60 sec exposure on it. My cadence is about one image every 3 minutes.

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Hi Arttu,
any progress with the ATEL? I replied to your private e-mail address a couple of days ago. In the meantime I have observed EF Eri for six consecutive nights. Data are with the AAVSO database (see attached screen shot)
Josch

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Hi Josch ,
I have received comments from everyone involved and addressed suggested edits as well as added the latest photometry. Updated version is available in Github. It has not been posted yet to ATel as I am still waiting for credential.

Arttu