Minutes
                     Einstein Users Committee Meeting
                               July 27. 1983
                           Center for Astrophysics

Attending were:

C. Canizares. MIT   P. Charles. GO     D. Harris. CFA
D. Helfand. CAL     J. Grindlay. CFA   L. Kaluzienski. NASA
F. Marshall. GSFC   F. Primini. CFA    F. Seward. CFA
H. Tananbaum. CFA   F. Walter. GO

I. IPC Processing

A. Status and Schedule

The "definitive" reprocessing began May 4. 1983. The science  
processing is currently complete up to May 3. 1979. Calibration data  
have been processed through September 26. 1980. The science  
processing is currently being held up. with the exception of Guest  
Observer requests. in order to complete processing of all calibration  
data. This calibration processing should be finished approximately  
August 3. All features are not yet implemented in the "definitive"  
processing. Not yet attempted are MAP Detect. Fourier analysis for  
variability. and limited sensitivity analysis. Currently running but  
not fully tested features are source extent analysis. anomalous  
emission analysis (XDETECT) and spectral analysis of sources in  
central region. (GRADSPEC).

It was suggested that a Raymond-Smith spectral analysis should be  
done as part of the GRADSPEC program. If space is a problem. the  
black body analysis. uninteresting in most cases. could be eliminated.

The science processing rate is currently about 1.5 real time and is  
expected to drop to 1.0 real time when the remaining programs come on  
line. MAP Detect should be finished by October 15. Sequences  
processed before this date (about 1.000) will have to be reprocessed  
through the DETECT and Source Properties parts of the system. which  
will take six to eight weeks. An additional sixty weeks are estimated  
necessary to process the remaining sequences. Thus reprocessing of  
all IPC data should be complete December 15. 1984.

It was suggested that CFA should keep a log of changes in the  
processing software and that this be made available to all.

B. Out of Sequence Processing

Ten percent of processing time is allocated to processing IPC  
observations out of chronological order. When the calibration data  
base is complete (mid August) any IPC observation can be processed on  
demand. subject to the limitations of: a) calibration data base not  
fully checked and b) out-of-sequence processing time requested  
exceeding the 10% limit. We have received requests for 79 sequence  
numbers and have processed 30 of these out of the normal  
chronological order.

If a proposal to use reprocessed IPC data should be received. these  
data could be processed out of normal sequence. so they would be  
available in the Bank in six months. The original owner would be  
notified of such early processing.

C. Notification

Every month owners of IPC fields which have been processed are  
notified that the processing has been accomplished. The Guest  
Observer copy of the computer printout generated is being mailed  
along with this notice. The printout associated with consortium  
observations is retained in the file at CFA and is available upon  
demand.

D. IPC Data Format

F. Walter presented the committee with a detailed list of inquiries  
on the reprocessed IPC output. Some errors and ambiguities were  
found. Errors will be corrected. and answers to other questions will  
be included in the new Users Manual. This sort of feedback is very  
useful. CFA would appreciate it if. errors and things which are not  
understandable are brought to their attention

II. MPC Processing

A. Status and schedule

The MPC data are currently being reprocessed in order to generate a  
new background map covering the entire flight at intervals of about  
two weeks. With this time and space dependent background map.  
accurate spectral data can be extracted for sources as weak as 0.3  
UFU. This processing must be done in the order in which data were  
taken. Observations cannot be processed out of their normal  
chronological order.

The reprocessing was started May 1. and the entire month was devoted  
to debugging. Approximately one month of flight data has now been  
reprocessed. The rate of reprocessing is about six tapes or two days  
of flight data per night. Eighteen months will be required to finish.  
The end result will be a data base in which all MPC spectral data are  
contained on one 200-megabyte disk pack. giving easy computer access  
to the entire data base.

B. Release to Data Bank

An observation will be released to the Data Bank as soon as  
reprocessing of
that observation is complete. This is the same policy followed for  
the IPC except that there is no six-month exclusive proprietary  
rights for the original observer. Thus a few MPC observations are  
available now and all observations will be available approximately  
December 1984.

Although TIP (time interval ~rocessor) data are nominally also  
available at the time the spectral observations are released.  
additional processing is necessary to extract these data from the  
flight tapes. This first step has never been done for many  
observations because these data are only useful if there is a source  
of at least moderate intensity in the field.

Any request for the MPC TIP data requires more data processing than  
requests for imaging data. Over the next 18 months special processing  
required to fulfill such requests will compete for time with the  
reprocessing of the spectral information. Thus a request for a large  
amount of MPC data is likely to be referred to NASA for  
prioritization. Occasional requests for individual targets should  
pose no problem.

III  Data Bank

A. Users

Forty-eight requests have been received for Einstein data. 44 since  
January 1. 1983. In most cases the user has simply taken the data  
requested or it has been shipped to him. In some cases the user has  
worked with the data at CFA as a Guest Observer. In some cases  
personnel at CFA have done the analysis and sent the results to the  
user.

A program is being written. to be used with the Einstein Observation  
Catalog. which will list under a given sequence number any use made  
of this information through the Data Bank. Thus in about two months.  
we can generate a list of sequence numbers and their Data Bank users.  
This information is expected to be most useful to potential users of  
the Data Bank who might wish to contact other users or who might want  
to search for a target that has not been extensively studied.

B. Notification of Users to Consortium

A list of Data Bank users and their projects was sent to members of  
the Users Committee March 28 and a second list distributed at this  
meeting. Members of the Committee are free to circulate this  
information to interested parties at their home institutions. but no  
further distribution in planned by the Data Bank.

C. SSS and FPCS Data

These data are considered to be in the Bank now and available for  
Guest Observers. Both GSFC and MIT have stated that. since they do  
not get funding to support users. any use of these data requiring  
their time and effort should be a collaboration between people at the  
host institution and the guest. So far. there has been only one  
request for spectral information through the Data Bank. Information  
from the FPCS was sent to these users with no conditions attached.

Two members of the Committee stated they had been involved in  
collaborative projects using SSS spectra with people at GSFC. They  
were not happy with all the arrangements. which were worked out  
person to person on an informal basis. and hoped that potential Data  
Bank users could be handled more efficiently. Specifically. the  
number of Goddard coauthors accreted was thought to be high for the  
effort involved. and these coauthors were found to be so busy with  
other projects that the work proceeded extremely slowly. GSFC stated  
that they would investigate the matter and that potential users  
should be advised to spend time at the host institution so that the  
work would proceed more quickly.

Use of spectral data by outsiders qualified to run the data analysis  
was also discussed. An example of such users are those who used to be  
associated with consortium institutions and were at one time deeply  
involved in the data analysis. Since support for such users in the  
way of office space and computer use is required. requests from this  
group will still have to be considered on an individual basis.

It was asked if the spectral information (SSS and OGS) could be made  
available in a simple format--a catalog of spectral information which  
might satisfy many requirements of Data Bank users. Such a catalog.  
for example. would be useful in planning EXOSAT observations. At the  
present time there is no funding for such a catalog, but the question  
could be raised at an upcoming FY8S BEAO-II review by NASA.

IV. New CFA Publications

A. Users Manual

The Users Manual is being rewritten and will contain descriptions of  
the new HRI and IPC data formats as well as updated descriptions and  
recipes for using analysis software. The present loose-leaf form will  
be retained. with the addition of page numbers and black edges  
separating major sections to make the volume easier to use. A request  
was made to list analysis programs available at CAL, since some of  
these might be useful to guests handling Einstein data. The new Users  
Manual will be available in November or December when the new IPC  
programs. such as MAP Detect. are incorporated in the processing.

Rather than mailing the manual to all Guest Observers as in the past.  
a table of contents will be sent to all and the complete Manual sent  
only to those who request it.

B. Yellow Book

The Einstein catalog sorting program is being rewritten to eliminate  
two errors present in past versions of the yellow book. Presently  
targets with declinations between 00 and -10 are listed as being  
between 00 and +10. There are also targets which have been left out  
of the category listing because the category number is wrong and the  
computer is unable to bring this to our attention. The new program  
will be finished in September and a new yellow book issued in  
October. Targets will be listed by right ascension and by sequence  
number as well as category.

v. Other Business

A. Software Problems

Software developed for Rev. 0 data does not automatically work on the  
Rev. 1 IPC data. We are currently modifying software so that all  
standard programs--TIMEOUT. FINSPEC. etc.--work on both Rev. 0 and  
Rev. 1 data. It is important to realize that at present time are two  
types of IPC data available. It is worthwhile verifying that you have  
the proper version on the computer disk to start with. Any problems  
encountered with software should be brought to the attention of CFA.

B. Data and Software for Export

The desirability of a standard format for both Einstein data and for  
software was discussed. CFA is presently capable of generating FITS  
tapes. which can be read at most other institutions. and. of course.  
there is no problem with information from printouts. Difficulties  
have been encountered with lists of event times which are currently  
written as floating point numbers. CFA will investigate the  
possibility of generating this information in a format more easily  
readable by those with other computers. CFA stated that they would  
usually send software programs to people requesting them. but there  
was no time or effort available for rewriting these programs in a  
different Fortran format.

C. Modems

The CFA computer currently has one modem available for long distance  
users. Use of this facility. if reasonable. is no problem.

D. Proposal Review

A Guest Observer proposal review was held in May. Fourteen proposals  
were reviewed and 11 were accepted.  A deadline of 1 October is set  
for submission of proposals to be considered at the next review. This  
deadline will be mentioned in the next newsletter sent by CFA to  
Guest Observers.

E. Next Meeting

The next Users Committee meeting will be scheduled after an interval  
of six to twelve months.