Dear colleagues,

We are pleased to announce the Version 1.0 release of Epoch 1 of MACSJ0717.5+3745, after the completion of the first 70 orbits of ACS and WFC3/IR imaging on this cluster and its parallel field from our Frontier Fields program ID 13498 (PI: J. Lotz). These full-depth v1.0 mosaics also include archival ACS and WFC3/IR data in the Frontier Fields filter set, from programs 9722 and 10420 (PI: H. Ebeling), programs 10493 and 10793 (PI: A. Gal-Yam), program 12103 (PI: M. Postman), program 13389 (PI: B.Siana), and program 13459 (PI: T. Treu). These v1.0 mosaics have been fully recalibrated relative to the v0.5 mosaics that we have released during the course of this epoch in October and November 2014. For ACS, the v1.0 mosaics incorporate new bias and dark current reference files, along with CTE correction and bias destriping, and also include a set of mosaics that have been processed with the new selfcal approach to better account for the low-level dark current structure. The WFC3/IR v1.0 mosaics have improved masking for persistence and bad pixels, and in addition include a set of mosaics that have been corrected for time-variable sky emission that can occur during the orbit and can otherwise impact the up-the-ramp count-rate fitting if not properly corrected. Further details are provided in the readme file, which can be obtained along with all the mosaics at the following location:

* Latest mosaics: http://archive.stsci.edu/pub/hlsp/frontier/macs0717/images/hst/v1.0-epoch1/
* All mosaics: http://archive.stsci.edu/prepds/frontier/macs0717.html


More general information about the data for the Frontier Fields project can be obtained from our Frontier Fields MAST archive website:
* http://archive.stsci.edu/prepds/frontier/
as well as our main Frontier Fields HST project website:
* http://www.stsci.edu/hst/campaigns/frontier-fields/
and our Frontier Fields astronomer's blog and other social media:
* https://blogs.stsci.edu/hstff/
* https://twitter.com/MAST_News/
* https://facebook.com/MASTArchive/

We hope that these high-level science products are useful for your research, and we welcome any suggestions or questions that you may have about them.

Best regards,
Anton Koekemoer
and the STScI Frontier Fields Team
http://archive.stsci.edu/prepds/frontier/
http://www.stsci.edu/hst/campaigns/frontier-fields/Contact