What vpmanager does:
-
Set a Given Telescope’s VP/PB model
-
The
vpmanager
recognizes
the
names
of
several
telescopes:
ATCA,
GBT,
GMRT,
HATCREEK,
NMA,
NRAO12M,
NRAO140FT,
OVRO,
VLA,
WSRT.
New
telescopes
and
their
default
VP/PB
models
will
need
to
be
added
to
the
system.
-
Common VP/PB Models
-
Many
common
voltage
pattern
(vp)
and
primary
beam
(pb)
models
have
been
coded
into
CASA.
Currently,
the
recognized
models
include
DEFAULT,
ATCA_L1,
ATCA_L2,
ATCA_L3,
ATCA_S,
ATCA_C,
ATCA_X,
GBT,
GMRT,
HATCREEK,
NRAO12M,
NRAO140FT,
OVRO,
VLA,
VLA_INVERSE,
VLA_NVSS,
VLA_2NULL,
VLA_4,
VLA_P,
VLA_L,
VLA_C,
VLA_X,
VLA_U,
VLA_K,
VLA_Q,
WSRT,
and
WSRT_LOW.
In
all
cases,
the
VP/PB
model
and
the
beam
squint
(if
present)
scale
linearly
with
wavelength.
If
DEFAULT
is
selected,
the
appropriate
VP/PB
model
is
selected
for
the
telescope
and
observing
frequency.
-
1-D Beam Models
-
Most
beam
models
are
rotationally
symmetric
(excepting
beam
squint).
From
the
beam
parameterization
in
terms
of
the
various
coefficients
and
other
terms,
an
internal
lookup
table
with
10000
elements
is
created
for
application
of
the
VP/PB
to
an
image.
-
Beam Squint
-
The
VP/PB
models
include
beam
squint.
The
VLA_L,
VLA_C,
VLA_X,
VLA_U,
VLA_K,
and
VLA_Q
models
(which
are
the
defaults
for
those
VLA
bands),
have
the
appropriate
squint
magnitude
and
orientation,
though
the
orientation
has
not
been
verified
through
processing
actual
data.
-
Multiple VP/PB Models for one MS
-
The
VPManager
can
have
VP
information
for
multiple
telescopes.
However,
the
internals
of
imager
cannot
yet
deal
with
VP/PB’s
for
multiple
telescopes.
In
the
case
of
a
MS
with
multiple
telescopes
present,
the
primary
beam
of
the
first
telescope
present
in
the
MS
will
be
used,
even
if
it
is
not
the
first
telescope
specified
in
the
VP
description
table
produced
by
vpmanager.
-
Antenna-dependent Voltage Patterns
-
are
not
yet
supported.
-
Two-dimensional Voltage Pattern Images
-
are
supported
via
setpbimage.
Please send any comments or questions about CASA or AIPS++
to aips2-requests@nrao.edu
Copyright © 2008 Associated Universities Inc.,
Washington, D.C.
This code is available under the terms of the GNU General Public Lincense
Home |
Contact Us |
Directories |
Site Map |
Help |
Privacy Policy |
Search
Updated daily during alpha development.
