MOBSTER collaboration member Dr. Matt Shultz was recently featured in a UDaily spotlight piece by the University of Delaware for his work revealing the connection between gyrosynchrotron radiation and the rotation rates of magnetic massive stars. Read more in the MOBSTER VI paper here!
The sixth MOBSTER collaboration paper has been published!
MOBSTER – VI. The crucial influence of rotation on the radio magnetospheres of hot stars
M. E. Shultz, S. P. Owocki, A. ud-Doula et al., 2022, MNRAS, 513, 1429
In this paper, we address gyrosynchrotron radio emission in magnetic hot stars. We present and analyse an exhaustive list of radio measurements of magnetic early-type stars available in the literature (131 stars, with 50 that are radio-bright). The dependance of gyrosynchrotron radiation on stellar rotation is examined. We also explore the relationship between radio luminosity and Hα emission, which suggests that radio emission may result from electrons that have been accelerated in centrifugally driven magnetic reconnection events.
The MOBSTER-2 Virtual Workshop was held on November 9th and 12th 2021.
Following up on last year’s MOBSTER-1 Virtual Conference, we organized a more self-contained virtual workshop reuniting MOBSTER members for two days over the second week of November. In total, 10 presenters gave talks to their fellow MOBSTERs, with a hands-on tutorial given by Dr. Jon Labadie-Bartz on TESS data retrieval and reduction. Overall, attendees were treated to a great variety of scientific topics, with a particular focus on magnetospheres, HgMn and mCP stars.
It was good seeing everyone and we hope to build on this momentum moving forward into 2022!
Following last summer’s successful virtual conference, we have gathered and published proceedings for most of the presentations. Everything is available in a dedicated Zenodo community, with video files uploaded for talks and pdf files uploaded for posters.
While there are still a few contributions missing, the proceedings are now 85% complete (with more to come possibly over the next following weeks). We thank once again all of our contributors and attendees!
The fifth MOBSTER collaboration paper has been published!
MOBSTER – V. Discovery of a magnetic companion star to the magnetic β Cep pulsator HD 156424
M. E. Shultz, Th. Rivinius, G. A. Wade et al., 2021, MNRAS, 504, 4850
HD 156424, a previously known magnetic pulsator, is found to have a binary companion that is also magnetic, making this system only the second doubly-magnetic massive binary known to this day (the other being ɛ Lupi). The estimated magnetospheric extent of both components suggests that they are interacting.
The fourth MOBSTER collaboration paper has been published!
MOBSTER – IV. Detection of a new magnetic B-type star from follow-up spectropolarimetric observations of photometrically selected candidates
A. David-Uraz, M. E. Shultz, V. Petit et al., 2021, MNRAS, 504, 4841
We report the first new detection of a magnetic field by the MOBSTER Collaboration in the late B-type star HD 38170. This detection was obtained in the context of a spectropolarimetric follow-up program that acquired data for 4 magnetic candidates with rotationally modulated light curves, yielding a detection rate that is greater than the overall incidence rate of magnetic OBA stars.
The third MOBSTER collaboration paper has been published!
MOBSTER – III. HD 62658: a magnetic Bp star in an eclipsing binary with a non-magnetic ‘identical twin’
M. E. Shultz, C. Johnston, J. Labadie-Bartz et al., 2019, MNRAS, 490, 4154
We report the discovery of an eclipsing binary system comprising a late B-type magnetic star and a nearly identical twin: the only obvious difference between both stars is that the secondary is non-magnetic. This test case places important constraints on the origin of magnetic fields in stars with radiative envelopes.
The second MOBSTER collaboration paper has been published!
MOBSTER – II. Identification of rotationally variable A stars observed with TESS in sectors 1-4
J. Sikora, A. David-Uraz, S. Chowdhury et al., 2019, MNRAS, 487, 4695
Using 2-minute cadence data from the first four sectors of TESS observations, we identify 134 high-probability candidate rotational variable A-type stars, of which a majority are classified in the literature as magnetic Ap stars. The light curve variations of rotationally modulated Ap stars differ quantitatively from those of rotationally modulated non-Ap stars, typically exhibiting higher amplitudes and longer periods.
The first MOBSTER collaboration paper has been published!
Magnetic OB[A] Stars with TESS: probing their Evolutionary and Rotational properties (MOBSTER) – I. First-light observations of known magnetic B and A stars
A. David-Uraz, C. Neiner, J. Sikora et al., 2019, MNRAS, 487, 304
In this introductory paper, we present the MOBSTER Collaboration and its main goals, before analyzing the light curves of 19 previously known magnetic B- and A-type stars, highlighting their diversity and commonalities. 13 of them seem to exhibit rotational modulation in their light curves, allowing for refined period determinations.
MOBSTER Collaboration 