  XTE J1701-407 is a newly discovered X-ray transient source. In this work we
investigate its flux variability and study the intermediate long and short
bursts discovered by Swift on July 17, and 27, 2008, respectively. So far, only
one intermediate long burst, with a duration of ~18 minutes and ten days later
a short burst, have been recorded from XTE J1701-407. We analyzed the public
available data from Swift and RXTE, and compared the observed properties of the
intermediate long burst with theoretical ignition condition and light curves to
investigate the possible nuclear burning processes. The intermediate long burst
may have exhibited a photospheric radius expansion, allowing us to derive the
source distance at 6.2 kpc assuming the empirically derived Eddington
luminosity for pure helium. The intermediate long burst decay was best fit by
using two exponential functions with e-folding times of \tau_1=40(3) s and
\tau_2=221(9) s. The bursts occurred at a persistent luminosity of
L_{per}=8.3x10E36 erg/s. For the intermediate long burst the mass accretion
rate per unit area onto the NS was \dot{m}=4x10E3 g/cm2/s, and the total energy
released was E_{burst}=3.5x10E40 erg. This corresponds to an ignition column
depth of y_{ign}=1.8x10E9 g/cm2, for a pure helium burning. We find that the
energetics of this burst can be modeled in different ways, as (i) pure helium
ignition, as the result of either pure helium accretion or depletion of
hydrogen by steady burning during accumulation, or (ii) as ignition of a thick
layer of hydrogen-rich material in a source with low metallicity. However,
comparison of the burst duration with model light curves suggests that hydrogen
burning plays a role during the burst, and therefore this source is a low
accretion rate burster with a low metallicity in the accreted material.
