Fitting BICEP2 with defects, primordial gravitational waves and dust
  In this work we discuss the possibility of cosmic defects being responsible
for the B-mode signal measured by the BICEP2 collaboration. We also allow for
the presence of other cosmological sources of B-modes such as inflationary
gravitational waves and polarized dust foregrounds, which might contribute to
or dominate the signal. On the one hand, we find that defects alone give a poor
fit to the data points. On the other, we find that defects help to improve the
fit at higher multipoles when they are considered alongside inflationary
gravitational waves or polarized dust. Finally, we derive new defect
constraints from models combining defects and dust. This proceeding is based on
previous works [1,2].
