Call for spectroscopic monitoring of X Per 2025 - Alexander Salganik

[Robin Leadbeater]

I have received a request from Alexander Salganik University of Turku for long term spectroscopic monitoring of the X Ray Binary X Per which I am relaying to the various spectroscopy groups. 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

Please also submit any spectra to the BAA database where you will also find over a hundred spectra from the previous monitoring period.
https://britastro.org/specdb/data.php
I will be adding it to my observing list again.



See below for more information from Alexander

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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.