Radio monitoring of the periodically variable IR source LRLL 54361: No direct correlation between the radio and IR emissions

Autor(en)
Jan Forbrich, Luis F. Rodriguez, Aina Palau, Luis A. Zapata, James Muzerolle, Robert A. Gutermuth
Abstrakt

LRLL 54361 is an infrared source located in the star-forming region IC 348 SW. Remarkably, its infrared luminosity increases by a factor of 10 over roughly one week every 25.34 days. To understand the origin of these remarkable periodic variations, we obtained sensitive 3.3 cm JVLA radio continuum observations of LRLL 54361 and its surroundings in six different epochs: three of them during the IR-on state and three during the IR-off state. The radio source associated with LRLL 54361 remained steady and did not show a correlation with the IR variations. We suggest that the IR is tracing the results of fast (with a timescale of days) pulsed accretion from an unseen binary companion, while the radio traces an ionized outflow with an extent of ∼100 AU that smooths out the variability over a period of the order of a year. The average flux density measured in these 2014 observations, 27 ± 5 μJy, is about a factor of two less than that measured about 1.5 years before, 53 ± 11 μJy, suggesting that variability in the radio is present, but over larger timescales than in the IR. We discuss other sources in the field, in particular two infrared/X-ray stars that show rapidly varying gyrosynchrotron emission.

Organisation(en)
Institut für Astrophysik
Externe Organisation(en)
Universidad Nacional Autonoma de Mexico, University of Massachusetts, Amherst, Harvard-Smithsonian Center for Astrophysics, Space Telescope Science Institute
Journal
The Astrophysical Journal
Band
814
Anzahl der Seiten
4
ISSN
0004-637X
DOI
https://doi.org/10.1088/0004-637X/814/1/15
Publikationsdatum
11-2015
Peer-reviewed
Ja
ÖFOS 2012
103003 Astronomie, 103004 Astrophysik
Schlagwörter
ASJC Scopus Sachgebiete
Astronomy and Astrophysics, Space and Planetary Science
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/radio-monitoring-of-the-periodically-variable-ir-source-lrll-54361-no-direct-correlation-between-the-radio-and-ir-emissions(f2aa4136-d9ff-4b5b-a271-f79895b75afa).html