A LIKELY MILLISECOND PULSAR BINARY COUNTERPART FOR FERMI SOURCE 2FGL J2039.6–5620

Journal Article · Tue Oct 20 04:00:00 EDT 2015 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/812/2/L24· OSTI ID:22518773

We have identified an optical/X-ray binary with an orbital period of P{sub b} = 5.47 hr as the likely counterpart of the Fermi source 2FGL J2039.6−5620. GROND, SOAR, and DES observations provide an accurate orbital period and allow us to compare to the light curve of an archival XMM exposure. Like many short-period optical/X-ray binaries associated with Large Area Telescope sources, this may be an interacting (black widow/redback) millisecond pulsar binary. The X-ray light curve is consistent with the emission associated with an intrabinary shock. The optical light curve shows evidence of companion heating, but has a peculiar asymmetric double peak. The nature of this optical structure is not yet clear; additional optical studies and, in particular, detection of an orbital modulation in a γ-ray pulsar are needed to elucidate the nature of this peculiar source.

• OSTI ID: 22518773
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 2 Vol. 812; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASYMMETRY
BINARY STARS
COMPARATIVE EVALUATIONS
COSMIC GAMMA SOURCES
COSMIC X-RAY SOURCES
DIAGRAMS
GAMMA RADIATION
HEATING
PULSARS
TELESCOPES
VISIBLE RADIATION
X RADIATION