%-----------------------------------------------------------------------
%;  Copyright (C) 2024
%;  Associated Universities, Inc. Washington DC, USA.
%;
%;  This program is free software; you can redistribute it and/or
%;  modify it under the terms of the GNU General Public License as
%;  published by the Free Software Foundation; either version 2 of
%;  the License, or (at your option) any later version.
%;
%;  This program is distributed in the hope that it will be useful,
%;  but WITHOUT ANY WARRANTY; without even the implied warranty of
%;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
%;  GNU General Public License for more details.
%;
%;  You should have received a copy of the GNU General Public
%;  License along with this program; if not, write to the Free
%;  Software Foundation, Inc., 675 Massachusetts Ave, Cambridge,
%;  MA 02139, USA.
%;
%;  Correspondence concerning AIPS should be addressed as follows:
%;          Internet email: aipsmail@nrao.edu.
%;          Postal address: AIPS Project Office
%;                          National Radio Astronomy Observatory
%;                          520 Edgemont Road
%;                          Charlottesville, VA 22903-2475 USA
%-----------------------------------------------------------------------
%Body of intermediate AIPSletter for 30 June 2024 version

\documentclass[twoside]{article}
\usepackage{graphics}

\newcommand{\AIPRELEASE}{June 30, 2024}
\newcommand{\AIPVOLUME}{Volume XLIV}
\newcommand{\AIPNUMBER}{Number 1}
\newcommand{\RELEASENAME}{{\tt 31DEC24}}
\newcommand{\NEWNAME}{{\tt 31DEC24}}
\newcommand{\OLDNAME}{{\tt 31DEC23}}
\newcommand{\THISYEAR}{2024}
\newcommand{\NEWYEAR}{2025}
\newcommand{\OLDYEAR}{2023}

%macros and title page format for the \AIPS\ letter.
\input LET98.MAC
%\input psfig

\newcommand{\MYSpace}{-11pt}

\normalstyle

\section{Happy 45$^{\rm th}$ birthday \AIPS\ and FITS}

The FITS format was devised in a meeting at the VLA site on March 27
and 28, 1979.  Don Wells (then of NOAO) and Eric Greisen (still of
the NRAO) were the primary authors while Barry Clark and other NRAO
staff members provided valuable suggestions.  The FITS format, enhanced
by later extensions, is still in wide spread use in astronomy and is the
envy of other scientific fields.  The FITS format then colored the
design of the \AIPS\ internal formats.  The \AIPS\ project was begun
officially on July 1, 1979 and has stood the test of time remarkably
well.

Your editor does find times when he would like interesting things to do.
If you find any problems with \AIPS\ or have any suggestions for new or
improved functions, please do not hesitate to e-mail {\tt daip@nrao.edu}.

\subsection{\Aipsletter\ publication}

We have discontinued paper copies of the \Aipsletter\ entirely.  The
\Aipsletter\ will be available in PostScript and pdf forms as always
from the web site listed above.  New issues will be announced in the
NRAO eNews mailing and on the bananas and MNJ list server.  Readers are
encouraged to subscribe to one of these low volume mail lists at
{\tt htps://listmgr.nrao.edu/mailman/listinfo}.

\subsection{Current and future releases}

We have formal \AIPS\ releases on an annual basis.  While all
architectures can do a full installation from the source files,
Linux (64-bit and for a little while longer 32-bit), and MacIntosh OS/X
(Intel and ARM) systems may install binary versions of recent releases.
The last, now actually ``frozen'' (was ``slushy'') release is called
\OLDNAME\ while \RELEASENAME\ remains under active development.  You may
fetch and install a copy of these versions at any time using {\it
  anonymous} {\tt ftp} for source-only copies and {\tt rsync} for binary
copies.  This \Aipsletter\ is intended to advise you of improvements to
date in \RELEASENAME\@. Having fetched \RELEASENAME, you may update your
installation whenever you want by running the so-called ``Midnight Job''
(MNJ) which copies and compiles the code selectively based on the
changes and compilations we have done.  The MNJ will also update sites
that have done a binary installation.  There is a guide to the install
script and an \AIPS\ Manager FAQ page on the \AIPS\ web site.

The MNJ for binary versions of \AIPS\ now uses solely the tool {\tt
  rsync} as does the initial installation.  For locally compiled
(``source'') installations, the Unix tool {\tt cvs} running with
anonymous ftp was used for the MNJ\@.  That has been replaced with
{\tt rsync} to download any changed text files.  The only installations
to still use {\tt cvs} are the five (now four) machines inside the
Socorro Array Operations Center.  Do not modify \AIPS\ text files
(\eg\ Fortran tasks) in the standard locations since {\tt rsync} will
over-write them.  For local versions, use a copy of the task and its
help file in a private disk area instead.

{\tt 31DEC20} contains a change to the TV display program {\tt XAS} that
makes it incompatible with previous releases when characters are
displayed.  {\tt 31DEC14} contains a change to the ``standard'' random
parameters in $uv$ data and adds columns to the {\tt SN} table.  Note,
however, that the random parameters written to FITS files have not been
changed.  Older releases of \AIPS\ cannot handle the new {\it internal}
$uv$ format and might be confused by the {\tt SN} table as well.  You
are encouraged to use a relatively recent version of \AIPS, whilst those
with recent VLA data to reduce should get release \OLDNAME\ or,
preferably, the latest development release.

\AIPS\ is now copyright \copyright\ 1995 through \THISYEAR\ by
Associated Universities, Inc., NRAO's parent corporation, but may be
made freely available under the terms of the Free Software Foundation's
General Public License (GPL)\@.  This means that User Agreements are no
longer required, that \AIPS\ may be obtained via anonymous ftp without
contacting NRAO, and that the software may be redistributed (and/or
modified), under certain conditions.  The full text of the GPL can be
found in the \texttt{15JUL95} \Aipsletter, in each copy of \AIPS\
releases, and on the web at {\tt http://www.aips.nrao.edu/COPYING}.

\section{``End of Life''}

The computers and/or the operating system versions that we have been
using to prepare the binary release of \AIPS\ are nearing what is called
the ``end of life.''  These are as follows:

{\bf LINUX} The {\tt LINUX} architecture has been maintained by a
venerable machine called dave which actually reached end of life in
2015.  The most modern operating system that it can run is RedHat 5!
In fact, dave was the main \AIPS\ computer until May 2022 holding the
source code for all versions on disks that were not backed up.  The
\AIPS\ system was moved to the file server at the Array Operations
Center (``filehost'') where it is now backed up on multiple time
intervals.  But dave has still been used to compute the 32-bit Linux
load modules using an Intel fortran version 9.1.043.  On June 21, 2024,
due to management decree, dave was turned off.  We are aware of only one
computer still using this architecture and it is capable of running the
64-bit version.  The {\tt LINUX} binaries for {\tt 31DEC24} and earlier
releases will now remain frozen.  There will not be a {\tt LINUX} binary
for the {\tt 31DEC25} release.

{\bf LNX64} The {\tt LNX64} architecture has been maintained by a
variety of computers running the RedHat 7 operating system.  That OS has
reached ``end of life'' at the end of June 2024.  The NRAO is
systematically updating all RedHat desktop systems to RedHat 8.  We have
therefore recompiled everything for RedHat 8.  It was already known that
RedHat 8 produces a fully usable binary \AIPS\ version and that Ubuntu
systems are happier with that version.  Ubuntu only needs one run-time
library with RedHat 8 rather than quite a number with RedHat 7.  {\tt
  31DEC23} will remain frozen at RedHat 7 when this conversion occurs;
no more ``patches'' will be applied.

{\bf MACINT} The {\tt MACINT} architecture has been maintained by a Mac
mini with an Intel cpu named gala-new.  The gfortran is at version
6.3.0.  This computer has been declared ``end of life'' since the
operating system cannot be upgraded past 12.6.4 and since it is labeled
as ``late 2014.''  We will continue to use gala-new to produce
Intel-based binaries until it has a hardware failure (or until
management decrees that it must go).  Mac users should consider
acquiring a more modern ARM computer.  That chip set is very fast.

{\bf MACARM}  The {\tt MACARM} architecture is maintained by a Mac
mini with an M1 cpu named gala that is dated 2020.  It currently runs
the 13.6.3 version of the operating system and gfortran 12.2.0.  The OS
will need to be updated to a $14.x$ version in the not too distant
future.  Previous experience with such ``upgrades'' suggests that
\AIPS\ will need to be entirely recompiled with an updated version of
gfortran.  Other issues may arise, such as those related to {\tt
  \$DISPLAY}\@.

{\bf {\tt 31DEC23} is now frozen and no more patches will be made.
  There has already been a bug corrected and an enhancement to TEC data
  handling that would have been made patches if that were still
  possible.  Users are encouraged to get the {\tt 31DEC24} release in
  order to remain current with corrections and improvements to the
  software.}

\vfill\eject

\section{Improvements of interest in \RELEASENAME}

We expect to continue publishing the \Aipsletter\ approximately every
six months, but the publication is now primarily electronic.  There is
one new task, one new verb and one new {\tt RUN} procedure in
\RELEASENAME\@.  These are, respectively, {\tt VH2RL} to convert a data
set between linear and circular polarization bases, {\tt STARTTV} to
restart the TV, message, and Tektronix servers, and {\tt CALMODEL} to
compute a model data set to be used with a new option in {\tt CALIB}\@.
The automatic download of total electron content data files has received
significant improvement and will not work in versions older than {\tt
31DEC22}\@.  A subtle but important change was made to {\tt FITLD}
which suggests that VLBA observers will need at least {\tt 31DEC23} if
not {\tt 31DEC24}\@.  Numerous bug fixes and minor improvements have
also been made.

\subsection{Polarization}

Like previous years, the study of polarization calibration has occupied
a lot of attention.  Given our difficulties with calibrating linear
polarization data, we investigated turning data in a linear basis into a
circular basis.  \AIPS\ Memo 125 (also EVLA Memo 229) is a detailed
report on our findings.  {\tt VH2RL} is the new task that converts
data from linear to circular or circular to linear.  The Memo explains
the use and limitations of this task.

{\tt PCAL}'s solution for linear polarization was rewritten to use
correct formul\ae\ and the application of the resulting D terms was
greatly simplified.  The previous code in {\tt PCAL} and in its
application does not make sense.  A new solution type {\tt V-H LIN} was
created to implement this change.  The old, mysterious code remains but
should not be invoked.  Studies with simulated data indicated that the
new code gets approximate solutions that are not quite correct despite
the use of correct formul\ae.  When the simulated data are converted to
a circular basis with {\tt VH2RL}, {\tt PCAL} gets answers that are
correct.

Task {\tt RLDIF} was enhanced with a table of position angles for 3C286
in the frequency range 0.561 to 1.071 GHz.  These values were derived by
Rick Perley and Ben Hugo from extensive observations with MeerKAT\@.
To allow for better calibration source models, the adverb {\tt ROTMEAS}
was added to {\tt RLDIF}\@.  The {\tt PP} file, which records the
polarization phase difference spectrum, was given an additional
parameter to record the polarization used in constructing the file.
The polarization is checked when applying the file and is displayed by
{\tt POSSM}\@.

The names of the total electron content data files have changed, but the
date at which the change occurred was different for different data
sources.  Lilia Tremou was instrumental in tracking down the multiple
changes for us.  Then the auto-download procedures {\tt VLBATECR} (in
{\tt VLBAUTIL}) and {\tt VLATECR} (in {\tt VLAPROCS}) were changed to use
a special procedure to control when the name format is changed.  The
name format also includes a code for the time interval in the data file,
which is 30 minutes in one case ({\tt TECRTYPE='CAS'}), one hour in
several cases, and two hours in the rest.  The procedures know which is
normal for a given {\tt TECRTYPE}, but if one interval fails they will
try the other.

The default magnetic field model was changed to the modern, time-varying
IGRF model in {\tt TECOR}\@.  That task now records the {\tt TT}
extension file version in the history.  Task {\tt MFIMG} was given an
adverb to let the user warn the task about the number of times in the
TEC data file being imaged.

\subsection{Analysis and display}

{\tt POSSM} again received considerable attention in this period.  The
$x$ axis labeling was not exactly correct, which was made obvious with a
data set with only 8 channels.  {\tt SOLINT} must be forced to zero for
{\tt BD} tables.  There were significant errors when plotting multiple
plots per page when there was more than one column of plots.  Changed it
to omit the IF number line in all but the last row of multiple plots
per page.  When {\tt BCHAN} was greater than 1 and/or {\tt ECHAN} less
than the max, there were issues with how those data were plotted.  When
the IFs have separator lines, then only {\tt BCHAN} to {\tt ECHAN} are
plotted in each sub panel.  When there are no separator lines, all
channels are plotted with those less than {\tt BCHAN} and greater than
{\tt ECHAN} in each IF blanked.  The computation of mean and rms in each
plot panel was changed to double precision since single precision
erroneously found rms of zero in some cases.

\vfill\eject

The graphics planes of the TV display is are sometimes used to compare
two or more versions of some parameter.  If one is plotted in graphics
channel one (yellow), the second in graphics channel two (green), then
pixels at which the values are the same show as a complementary color
(red in this case).  An option to specify the graphics channel to use
for labeling separate from the channel used for the rest of the plot
has been added generally.  If {\tt GRCHAN} $= 10 * x + y$, channel
$x$ will be used for labeling and $y$ for the rest.  If $y = 0$, some
tasks us graphics channel 1 and others use multiple graphics channels.
If $x = 0$, $x$ is set to $y$.

\begin{description}
  \myitem{PLOTR} was given the option of adding the fit parameters to
        the plot.
  \myitem{XAS} was changed to re-order the processes in the close down
        routine.  On Macs, the shut down of certain X Windows functions
        caused the program to stop without performing the operations
        that deleted link files and stopped the TV server d\ae mon
        process.  As a consequence, they proliferated.
  \myitem{STARTTV} is a new verb that will recreate any of the servers
        that may have disappeared.  This include the {\tt XAS} TV
        display with connecting TV server, the message server, and the
        ``Tektronix'' server.
  \myitem{IMEAN,} {\tt IMSTAT}, and {\tt TVSTAT} were given an option to
        tell them to include pure zero pixels in their computations of
        mean and rms.
  \myitem{MARSP} was given the option to read Q and U images as an
        alternative to total polarization and position angle images.
        An option to compute and display a histogram of the deviations
        of the position angles from radial was added as well as an outer
        radius parameter.
\end{description}

\subsection{UV data}

{\tt CALIB} was given the option to use a matching data set as a model.
One usage of this option would be if the same model were to be used for
different parameters in {\tt CALIB}\@.  For example, a phase-only
solution with a short {\tt SOLINT} followed by amplitude and phase on a
longer {\tt SOLINT} where the calibration source remains the same and
requires a model.  A new {\tt RUN} file and procedure {\tt CALMODEL}
were created to simplify creating the model data set.

\begin{description}
  \myitem{Application}\hspace{1em} of delay corrections to EVLA data was
        corrected.  A mis-alignment correction ({\tt FXSEG}) needed for
        the VLBA is not correct for the EVLA and introduced
        baseline-dependent offsets.
  \myitem{SPFLG} was corrected for an error that made the {\tt CLIP}
        options hard to reach.
  \myitem{FITLD} was changed to allow more than one pulse-cal table
        and to read data from rPICARD despite a FITS-format error.
  \myitem{VBRFI,} {\tt VLBRF}, and {\tt PLRFI} were changed to handle
        lower frequencies, to understand magic blanks properly, to allow
        study of RFI in the cross-hand polarizations, and to plot
        multiple plots per page.
  \myitem{}
\end{description}

\subsection{General}

Some effort has been expended in removing historic anachronisms from
\AIPS\@.  The {\tt NETSP} file is still used but the message complaining
about disk areas not listed therein has been suppressed.  The {\tt
  START\_AIPS} script was changed to omit the starting of the {\tt
  TPMON} servers since magnetic tapes are now rarely used and the usage
of remote disk-file reading with {\tt TPMON} was always unknown.
Similarly, the internet connection to the {\tt XAS} display server is
probably never used to let more than one computer talk to one display
window.  Therefore, {\tt START\_AIPS} was changed to, by default, use the
option ``{\tt tv=local:0}''.  To avoid the proliferation of server
windows, when exiting {\tt AIPS} users should employ {\tt KLEENEX}
rather than simply {\tt EXIT}\@.

\vfill\eject

\begin{description}
  \myitem{OBITVERS}\hspace{1.5em} default was changed to 3 as Python 2
        is on the way out.
  \myitem{install.pl} had a bug which caused {\tt MACARM} computers to
        use architecture {\tt MACINT}\@.  The data source for rsync will
        now be {\tt rsync.aoc.nrao.edu} rather than {\tt
        ftp.aoc.nrao.edu} although they are the same at present. That
        will change in the not too distant future.
  \myitem{Process} ID numbers are now rather longer than 5 digits on
        RedHat 8 and other systems.  Recognizing active tasks required
        correction to handle this.
  \myitem{AIPS} compilation procedures treated a file name containing the
        @ symbol as a list of files to compile and link.  This was
        changed to two at (@@) symbols to avoid conflict with account
        names containing an @ symbol.
  \myitem{\Cookbook} and other documentation files were updated in March
        and June fairly generally.  The typesetting of
        \Cookbook\ Chapter 13 was changed so that the automatic
        formatting of the chapter in the html and pdf versions would
        work with the linking to the actual help files.
  \myitem{Extension} files were removed from image and $uv$ data set
        headers without actually being deleted from the disk on error
        completion or even on normal completion in a couple cases.  This
        then leaves ``orphan'' files which may cause later failures.
        Tasks {\tt ACCOR}, {\tt ACSCL}, {\tt PRTSY}, {\tt SYPRT}, {\tt
          RLDIF}, {\tt VHDIF}, {\tt ISPEC}, {\tt RSPEC}, {\tt FRMAP},
        {\tt GAL}, and {\tt PLOTC} were corrected but only in {\tt
          31DEC24}\@.
\end{description}

\section{Recent Memoranda}

All \AIPS\ Memoranda are available from the \AIPS\ home page.  Memo 125
is a new memo to describe the conversion of linear to circular
visibility data.  It also appeared as EVLA Memo 229.  Further adventures
with VLA P-band polarimetry are described in EVLA Memo 230.

\begin{tabular}{lp{5.8in}}
{\bf 125} & {\bf Post-Correlation Basis Conversion in \AIPS}\\
   &  Rick Perley and Eric W. Greisen, NRAO\\
   &  April 16, 2024\\
   & Calibration and imaging of interferometric visibility data are much
simpler when the receiver systems are designed to provide output
voltages proportional to the circular components of the electric
field.  On the other hand, the antenna performance (sensitivity, and
polarization purity over wide bandwidths) is much better for data
taken with linear-basis receivers.  In this memo, we describe how
post-correlation visibility data can be converted from its original
linear basis to a circular basis. Doing so enables better calibration
and imaging while maximizing sensitivity and polarization purity.
Examples are given using VLA and MeerKAT data.
\end{tabular}

\begin{tabular}{lp{5.8in}}
{\bf 230} & {\bf Polarimetry with the VLA's P-band}\\
   &  Rick Perley and Eric W. Greisen, NRAO\\
   &  May 2, 2024\\
   & We continue our development of low-frequency polarimetry by
investigating the accuracy of the ionospheric Faraday rotation
corrections provided by the \AIPS\ program {\tt TECOR}\@. By observing
polarized sources through dawn and dusk, we conclude these corrections
successfully remove the IFRM with an accuracy of $\approx 0.1
\rm{rad}/{\rm{m}^2}$.  Subsequent polarimetric imaging of the Moon
reveals an unexpected, and unexplained residual rotation measure of
$\approx -0.75 \rm{rad}/{\rm{m}^2}$. This residual is seen in all six of
our observations, with values ranging from $-0.6$ to $-0.9
\rm{rad}/{\rm{m}^2}$. A similar offset is seen in observations of DA240
and 3C345, when comparing to WSRT observations.  Presuming this offset
is not associated with the sources in our observations, we have removed
it by utilizing the values determined from the lunar observations,
allowing the intrinsic source RMs and EVPAs for DA240, 3C303, and 3C345
to be determined.
\end{tabular}
\vfill\eject

\section{Patch Distribution for \OLDNAME}

Normally, this section lists the patches that have been released for
\OLDNAME\@.  This was based on the assumption that users would want to
download individual files to compile them locally.  However, the
``Midnight Job'' ({\tt \$HOME/do\_daily.}{\it hostname}) will do this
for you on locally-compiled installations.  It will also do a proper
update for binary installations.  Therefore there is no reason to
continue the old procedure.  Major bug corrections will be moved to
\OLDNAME\ as they occur and users should use the MNJ on occasion on both
the {\tt NEW} and {\tt TST} versions of \AIPS\@. The \OLDNAME\ release
has had a number of these ``patches'':

{\bf \large Because of the ``end of life'' matters discussed previously,
  no more patches will be made to {\tt 31DEC23}\@.  Usrs are encouraged
  to acquire {\tt 31DEC24}\@.}

\begin{enumerate}
  \item\ {\tt VBRFI}, {\tt VLBRF}, {\tt PLRFI} needed another digit for
    P-band and  needed corrections in plot scaling. {\it 2024-01-11}
  \item\ Unlike {\tt IMHEAD}, {\tt IM}{\it x}{\tt HEAD} verbs did not
    display keyword values. {\it 2024-01-18}
  \item\ {\tt VLBAUTIL.001} and {\tt VLAPROCS.001} needed a better if
      statement to set the downloaded file name for {\tt TECR}\@. {\it
        2024-01-26}
  \item\ Amplitude calibration for delay errors applied a correction to
      EVLA data that is only appropriate for VLBA data. {\it 2024-02-22}
  \item\ {\tt POSSM} needed to set {\tt SOLINT} to 0 for {\tt BD} tables.
      {\it 2024-02-27}
  \item\ {\tt POSSM} plotted the X axis incorrectly. {\it 2024-03-11}
  \item\ {\tt XAS.SHR} changed to reorder the close down operations.
      Macs do not finish the routine when X windows are closed.
      {\it 2024-05-15}
  \item\ {\tt install.pl} misidentified the {\tt MACARM} architecture as
      {\tt MACINT}. {\it 2024-05-15}
  \item\ The rsync host will be renamed to {\tt rsync.aoc.nrao.edu};
      changed {\tt UPDCONFIG} and {\tt install.pl}. {\it 2024-05-29}
  \item\ {\tt POSSM} had problems plotting {\tt CP} tables and other minor
      issues. {\it 2024-06-04}
  \item\ {\tt FITLD} had trouble with rPICARD files (which do not
      exactly match the FITS standard but are usable) and forced there
      to be only one {\tt PC} table version. {\it 2024-06-04}
  \item\ {\tt SUBIM} did not set {\tt TRC} properly when the axis
      increment was more than one. {\it 2024-06-10}
  \item\ {\tt install.pl} needed to change {\tt ftp.aoc} to {\tt
      rsync.aoc} in a second place. {\it 2024-06-10}
  \item\ Changed fetching of TEC files to account for the different
      dates at which the file names changed format.
      {\it 2024-06-13}
  \item\ {\tt UVFIT} had errors in the number of adverbs and the usage of
       the Clean Component output file. {\it 2024-06-17}
  \item\ {\tt SPFLG} clip menu items were not addressed properly.
      {\it 2024-06-18}
\end{enumerate}

\vfill\eject
\section{\AIPS\ Distribution}

We log apparent MNJ accesses and downloads of the tar balls and binary
installations.  We count these by unique IP address.  Since some systems
assign the same computer different IP addresses at different times,
this will be a bit of an over-estimate of actual sites/computers.
However, a single IP address is often used to provide \AIPS\ to a
number of computers, so these numbers are probably an under-estimate
of the number of computers running current versions of \AIPS\@.
So far in \THISYEAR\ more than 203 IP addresses have downloaded the
now frozen form of \OLDNAME, while more than 259 IP addresses have
downloaded \RELEASENAME\@.  A total of 418 different IP addresses have
appeared in one of our transaction log files.  These numbers are about
the same for {\tt NEW} and, for {\tt TST}, rather less than those of
last year at this time.

\vspace{1em}
\centerline{\resizebox{!}{4.5in}{\includegraphics{FIG/Plot2324a.eps}}}

%\vfill\eject
%\vfill\eject
%\hphantom{.}

\vfill\eject
% mailer page
% \cleardoublepage
\pagestyle{empty}
 \vbox to 4.4in{
  \vspace{12pt}
%  \vfill
\centerline{\resizebox{!}{3.2in}{\includegraphics{FIG/Mandrill.eps}}}
%  \centerline{\rotatebox{-90}{\resizebox{!}{3.5in}{%
%  \includegraphics{FIG/Mandrill.color.plt}}}}
  \vspace{12pt}
  \centerline{{\huge \tt \AIPRELEASE}}
  \vspace{12pt}
  \vfill}
\phantom{...}
\centerline{\resizebox{!}{!}{\includegraphics{FIG/AIPSLETS.PS}}}

\end{document}
