  High spatial resolution observation of an emerging flux region (EFR) was done
using a vector magnetograph and a H-alpha Lyot filtergraph with Domeless Solar
Telescope at Hida Observatory on October 22, 2006. In H-alpha wing images, we
could see many Ellerman bombs (EBs) in the EFR. Two observation modes, slit
scan and slit fixed, were performed with the vector magnetograph, along with
H-alpha filtergraph. Using H-alpha wing images, we detected 12 EBs during slit
scan observation period and 9 EBs during slit fixed observation period. With
slit scan observation, we found that all the EBs were distributed in the area
where the spatial gradient of vertical field intensity was large, which
indicates the possibility of rapid topological change in magnetic field in the
area of EBs. With slit fixed observation, we found that EBs were distributed in
the areas of undulatory magnetic fields, both in vertical and horizontal
components. This paper is the first to report the undulatory pattern in
horizontal components of magnetic field, which is also evidence for emerging
magnetic flux by Parker instability. These results allow us to confirm the
association between EBs and emerging flux tubes. Three triggering mechanism of
EBs is discussed with respect to emerging flux tubes: 9 out of 21 EBs occurred
at the footpoints of emerging flux tubes, 8 out of 21 EBs occurred at the top
of emerging flux tubes, and 4 out of 21 EBs occurred at unipolar region. Each
case can be explained by magnetic reconnection in the low chromosphere.
