sPHENIX is a new detector at RHIC.

[Martin Purschke <purschke AT bnl.gov>]

Dear all,

I'm planning to submit the attached abstracto to the CPAD (
http://physics.unm.edu/CPAD2017/  ) meeting.

There is also a satellite DAQ workshop preceding the meeting, where I'll
try to get a slot as well.

Please send me comments and suggestions what to improve.

        Martin


-- 
Martin L. Purschke, Ph.D.        ;   purschke AT bnl.gov
                                 ;   http://www.phenix.bnl.gov/~purschke
                                 ;
Brookhaven National Laboratory   ;   phone: +1-631-344-5244
Physics Department Bldg 510 C    ;   fax:   +1-631-344-3253
Upton, NY 11973-5000             ;   skype: mpurschke
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The sPHENIX Collaboration at RHIC is upgrading the PHENIX detector in
a way that will enable a comprehensive measurement of jets in
relativistic heavy ion collisions. The upgrade will give the
experiment full azimuthal coverage within a pseudorapidity range of
$-1.1 < \eta < 1.1$.

The apparatus consists of elctromagentic and hadronic calorimeters,
and an inner tracking system, which will consist of a silicon detector
based on MAPS (Monolithic Active Pixel Sensors), followed by an
Intermediate Tracker (INTT), and then by a TPC. With the exception of
the INTT, which is based on the former PHENIX Forward Vertex Detector
and also re-uses the readout technology, both the MAPS detector and
the TPC introduce new readout hardware and strategies.

In order to achieve high event rates, the TPC needs to be read out in
continuous, or streaming, mode, without the use of a gating grid. The
resulting continuously sampled waveforms of the TPC sensors must then
be processed and correlated with the actually triggered events of the
full detector.

The TPC using the ALICE Sampa ASIC. We will be using a card in use in
the ATLAS experiment, called "FELIX", which is PCIe-based and
has a large number (up to 48) of duplex fiber inputs to connect to the
front-end cards, and a powerful FPGA for waveform processing.

The MAPS detector will use the FELIX card for its readout as well.

We will present the envisioned design of the streaming readout, and
explain the challenges with the high data rates generated by this
readout method, which is likely to exceed 80 GBit/s. We will show the
design of our data acquisition to cope with those data rates, and
present the status of the ongoing R&D. Since many future experiments
are looking info streaming, trigger-less readout technologies, we will
put some emphasis on the still-evolving design of this aspect of the
readout.