RXTE News: Cycle 5, E-data, HEXTE tools, PCA backgrounds

[Alan Smale <alan@osiris.gsfc.nasa.gov>]

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        RXTE News: Cycle 5, E-data, HEXTE tools, PCA backgrounds
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We'd like to bring RXTE enthusiasts up to date on some recent
developments. This message contains information about:

 * The newly-released RXTE Cycle 5 observing program

 * Electronic distribution of RXTE GO data

 * A patch to the HEXTE FTOOLS

 * New PCA background models for Epoch 1


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** (1) The RXTE Cycle 5 Program
-------------------------------

	The RXTE Cycle 5 Peer Review process is complete, and letters
were sent out to all proposers two weeks ago. The list of accepted
Cycle 5 targets can be viewed online by going from the GOF Webpage
(http://rxte.gsfc.nasa.gov/) to the " Timelines" page, and clicking on
"RXTE Cycle 5 Approved Observing Program".


** (2) Electronic distribution of RXTE GO data
----------------------------------------------

	At the beginning of October we inaugurated a new GOF online
service to provide data to GOs over the Internet. In the online area
ftp://legacy.gsfc.nasa.gov/xte/data/archive/PGPData, we create a
PGP-encrypted tarfile for each ObsID as soon as we receive it from the
the processing facility, and notify the relevant PI by Email. The PI
then has 60 days to retrieve the data. (PGP-encrypted data is only
generated for proprietary data; methods for retrieval of public data
remain unchanged.)

	This service was introduced with the twin goals of reducing
costs and improving the efficiency of data throughput. Currently the
online service coexists with the XSDC service of distributing data on
tape. After a short overlap period, tape distributions will cease and
the online service will become the sole means of obtaining GO data.


** (3) A patch to the HEXTE FTOOLS
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	An FTOOLS update is now available containing (among other
things) improved versions of the tools HXTBACK, HXTDEAD, HXTLCURV,
HXTARF, and HXTRSP. Analysts with an interest in HEXTE data should
download the patch and install it on top of their existing FTOOLS 4.2
distribution, as described on the FTOOLS page --
     http://heasarc.gsfc.nasa.gov/ftools/ftools_update.html

This is a binary patch-kit, available for Sun (4.x & Solaris), Linux
(PC), OSF, and IRIX.  On the current schedule, FTOOLS 4.3 is due for
release in early 2000.


** (4) New PCA Background Models for Epoch 1
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	Finally, we'd like to draw your attention to the newly released 
PCA background models applicable to gain Epoch 1 (launch through 3/21/96).
The PCA Team has developed both bright and faint source models covering
these dates, with performance in both regimes comparable to Epoch 3
background subtractions.

	This is the first faint source background model applicable to
Epoch 1 data.  It is derived from background accumulated during Epoch
1, and uses the same combination of measured rates as the Epoch 3
"L7-240" model to estimate the background for any given observation.
Sources with observed count rates less than about 64 counts per second
per PCU *before* background subtraction are well suited to the faint
model.

	The latest bright source model for Epoch 1 replaces the
previously-released "Earth VLE" model, which was found to have a
significant problem for Epoch 1 observations.  (This problem was not
present in the Q6 Epoch 1 models.)  The new model is an extension of
the successful Epoch 3 "sky-VLE model" and is based on now hundreds of
background pointings and the behavior of the VLE rate as a function of
satellite parameters.  Initial testing of sources at the faint/bright
threshold shows that comparable spectral parameters and fluxes are
obtained with each model.
	
	Note that all Epoch 1 data is now in the public domain.  We
expect these greatly improved background models will be useful for
archival investigators as well as the original PIs of the Epoch 1
observations.  For information on how to download and apply the new
Epoch 1 background models to your observations, please visit the PCA
Digest page at http://xte.gsfc.nasa.gov/docs/xte/pca_news.html.


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| Dr. Alan P. Smale                | xtehelp@athena.gsfc.nasa.gov (RXTE)|
| RXTE Guest Observer Facility     | alan@osiris.gsfc.nasa.gov (me)     |
| Code 662,  NASA/GSFC             | (301) 286-7063 (voice)             | 
| Greenbelt, MD 20771, USA         | (301) 286-1682 (FAX)               |
|              RXTE GOF homepage: http://rxte.gsfc.nasa.gov             |