› Forums › Variable Stars › Request for monitoring of X Per (visual, digital and spectroscopic)
- This topic has 6 replies, 4 voices, and was last updated 2 weeks, 3 days ago by
Jeremy Shears.
-
AuthorPosts
-
26 July 2025 at 10:50 am #630769
Jeremy Shears
ParticipantPlease see the info below from Alexander Salganik, Turku University, of the very bright (6.0 to 6.8V) variable, X Per.
He provides the following further info, but please also upload your photometry (visual and digital) and spectroscopy to the BAA VSS databases:
“ I’d be happy to receive spectra directly. The main focus is on the Hα line at 6563 Å, and the higher the resolution the better, as we’re particularly interested in profile changes over time. If observers are able to include He I 6678 Å, He I 5876 Å or Hβ 4861 Å, that would also be very helpful, but Hα is definitely the priority.
Regarding photometry, UBVRI coverage would be ideal if observers have the filters and the time. If not, R and V bands are the most important, with R being especially valuable due to its sensitivity to emission from the circumstellar disk.
Visual observations are also absolutely welcome: the more data, the better.”
Original message:
I’m hoping this message can reach as many BAA members as possible who might be interested.
I would like to propose restarting an optical spectral monitoring programme for the Be star X Persei, the optical counterpart of the X-ray pulsar system 4U 0352+309.
My current research, as a PhD researcher at the University of Turku, Finland, focuses on the long-term X-ray light curve of 4U 0352+309 using data from Swift/BAT. Since around 2001, the source has exhibited three X-ray outbursts, occurring approximately every seven years. However, the next expected outburst has not occurred. Instead, the X-ray flux has dropped to its lowest level in over two decades.
This unusually low state makes continued optical monitoring particularly valuable. In particular, high-resolution observations of the H α line profile and the overall spectral shape, or even just measurements of the H α equivalent width (EW), would be extremely helpful.
If there is interest within the BAA community, even a single observation per week would be highly appreciated and scientifically valuable.
Thank you for your time and consideration.
Best regards,
Alexander SalganikAlsalganik at gmail.com
26 July 2025 at 10:52 am #630770Jeremy Shears
ParticipantA chart and sequence for visual observers is here: https://britastro.org/vss/xchartcat/x-per-277.html
26 July 2025 at 3:11 pm #630773john simpson
ParticipantWould there be any interest to receive polarimetry data?
27 July 2025 at 2:52 pm #630780Robin Leadbeater
ParticipantHere is some further information from Alexander on the spectroscopy side which I have been asked to also distribute to the wider spectroscopy community. It is similar monitoring to that requested by Paul Roche which covered mainly 2018-2021 and was reported on the ARAS and BAA forums
https://www.spectro-aras.com/forum/viewtopic.php?t=2128
https://britastro.org/forums/topic/request-for-monitoring-of-x-per————————————————————————————-
Call for Spectroscopic and Photometric Monitoring of X Persei (4U 0352+309)Observers are invited to join a monitoring campaign on the Be/X‑ray binary X Persei, which is currently in an unusually low X‑ray state.
The campaign is coordinated by Alexander Salganik, PhD researcher at the University of Turku, Finland, whose work focuses on the Swift/BAT X‑ray light curve of the system. Since 2001 X Persei has shown three major X‑ray outbursts roughly every seven years. The next expected outburst has not occurred, and the source now sits at its lowest X‑ray flux in more than twenty years. Optical monitoring will help determine the current state and physical properties of the Be star’s disk, including whether it remains present or has dissipated during this faint phase.
Spectroscopy: priority is high‑resolution Hα (6563 Å). Additional coverage of He I 6678 Å, He I 5876 Å, or Hβ 4861 Å is welcome. Target cadence is one observation per week.
Photometry: UBVRI is very welcome. If limited, R and V bands are most useful, with R particularly sensitive to disk emission.
Data can be sent directly to Alexander Salganik (alsalganik “at”gmail.com), who will provide regular feedback and campaign updates.
27 July 2025 at 4:51 pm #630781Paul G. Abel
ParticipantHappy to observe this!
27 July 2025 at 8:34 pm #630782Jeremy Shears
ParticipantExcellent, Paul!
29 July 2025 at 8:32 pm #630799Jeremy Shears
ParticipantHello John,
I asked Alexander about polarimetry and he says “my quick research shows that no polarimetric monitoring has been done for X Persei in quite a long time (since 1994), at least not in the published literature.”
If he finds more info, he will get back to me.
Go well!
Jeremy -
AuthorPosts
- You must be logged in to reply to this topic.