Contents

1. Spokesman's Column
2. STAR Operations
3. Persona Grata
4. STAR Software and Computing
5. Period Coordinators Report
6. Physics Working Groups
7. People: Service Jobs and more
8. Announcements, Papers and Notes
9. Employment Opportunities

Spokesman's Column (Tim Hallman)

Dear Fellow STAR Collaborators,

Greetings and welcome to the first edition of the STAR Newsletter in the new year.

One of the first things to mention is that the newsletter has a new Managing Editor, Spiros Margetis. I know you join me in welcoming Spiros and saying thanks once again to Howard Matis who held this position previously.

This year is starting just as busily as last year ended, with lots of new physics results being readied for review and publication. On the detector front, a number of dedicated folks worked hard over the holiday period (thanks to all!) to get a STAR interaction trigger up and running. This has resulted in first d+Au collisions having already been observed in the Time Projection Chamber, as one can see from the STAR image on the BNL home page. We are close to normal data taking activities and to beginnning to acquire our minimum bias data set. Work is continuing to include several additional detectors in the data stream and fully commission the barrel EMC.

The entire community is excited to see first results from the d+Au run and to find out what they will tell us about the interpretation of our results from AuAu running last year.

In late December, STAR took another important step, presenting its R&D plans and vision for the future physics program to the newly formed Detector Advisory Board. This is the beginning of an intensive program of simulation and R&D directed towards future upgrades of the STAR detector which will significantly extend our physics reach. These plans will also be discussed by the BNL HENP Program Advisory Committee in early summer. All things considered, 2003 is looking as though it will be a truly exciting year for STAR. With continued hard work and the kind of vision and energy STAR Collaborators have brought to our program in the past, we can all look forward to a truly banner year with many new and exciting scientific results.

Sincerely, Tim Hallman

STAR Operations (Bill Christie)

Status of STAR Commissioning for the FY03 d-Au physics run
----------------------------------------------------------------
Greetings from frigid Long Island. The commissioning of the collider proceeded more or less on schedule this year. Starting the evening of December 27th, d-Au collisions were made available for detector commissioning on the Owl shifts (~10:00 pm to 9:00 am). After giving a rough chronology of the STAR commissioning efforts, I'll give a more detailed synopsis of where things stand as of today (Jan. 17th). A small group of us started working each evening beginning December 27th to bring STAR online during these overnight shifts, concentrating primarily on the trigger electronics and "trigger" detectors (i.e. ZDCs, CTBs, BBCs). Blair Stringfellow started purging Argon gas into the TPC (displacing the Nitrogen) on January 2nd, and then started introducing Methane into the TPC on the afternoon of January 4th, which coincided with the start of 24 hour per day shifts at STAR. The TPC gas system was turned on January 5th, and has been running smoothly since. It was decided last Sunday evening, January 12th, that the collider commissioning was officially over, and that the Physics running had began. The practical impact of this decision on our commissioning efforts is that we nominally get collisions 24 hours/day, and we can move the bulk of our commissioning efforts to the day shift. We progressed with our trigger efforts to the point early Saturday morning, January 11th, where we decided to turn on the TPC and try and look at some events. With only minor exceptions, the TPC came up without any difficulty, and we started taking some test data. We immediately tried to bring the L3 trigger and display system online, and within an hour or so, with the setting of some format parameters to the appropriate values in the appropriate places, the L3 display was online and allowing us to get our first look at what a d-Au event at these energies looks like. Alex, Marcia, Steve and the BEMC group had been working for a number of days by this time getting setup so that they could adjust the timing of the digitizer gates for the BEMC tower readout electronics.  The BEMC was put into the data runs, and even at the relatively low average event rate (due to various bugs spread throughout a number of systems) they were able to set this gate timing by Monday morning, January 13th. At this point the BEMC group started the task of determining the relative gains of the BEMC towers by looking at the MIP peaks in the towers. By Tuesday, January 14th, Alex could show the first plot of the relative gain distribution for the towers. On Saturday afternoon (or Sunday?) January 11th, Frank started bringing up the voltages on the FTPCs, and observing clusters and what appear to be tracks. Since then the FTPC voltages have been brought up to their nominal operating voltages. Throughout the commissioning period, tuning and debugging of DAQ and Run Control has been going on, and the trigger work has continued non stop.Now for a few of the details: Our highest priority has been to get the trigger system as fully functional as possible, and then to perform some trigger studies, and try and determine what we'll want to use this year as our "min-bias" d-Au trigger. A strategy and implementation has been adopted whereby our "d-Au min-bias" Run Configuration this year will contain a number of Trigger conditions, each of which are identified by what are termed "Trigger Identifiers", which will run in parallel. There are a number of beneficial aspects to running with this strategy. One of these aspects, which we are taking advantage of as of yesterday (Thursday January 16th) is that we can start accumulating "min-bias" d-Au events immediately, and then add additional trigger conditions, and their associated Trigger Identifiers, as various necessary trigger studies are done, analyzed, and understood. It is anticipated that there will be substantial overlap in the events selected with this set of min-bias trigger conditions.At present, the d-Au Run Configuration contains two trigger conditions. These are:
 

1.) ( ZDC_East_Sum_adc > 5) + (25 < ZDC_East_TAC < 225) + (B+Y)
2.) (ZDC_East_Sum_adc > 5) + (ZDC_West_Sum_adc > 5)
 

 Condition #1 requires that the ZDC on the side of the STAR hall that sees the neutrons from the Au Nucleus has an energy deposition that is greater than that due to an ~ 15 GeV neutron (N.B. neutrons that are "tickled off of the Au beam nuclei will have energies of ~100 GeV), a very loose timing cut for the signal in this same East ZDC (~ 30 ns), and the requirement that a filled bunch should be traversing the IR in both the Blue and Yellow RHIC rings. As we are running at this time with a 120 bunch pattern in the RHIC collider, this last condition on (B+Y) is primarily to watch for malfunctions of the V124 timing modules or fills which miss the desired RF buckets in RHIC. This first trigger condition is essentially one that was suggested by Zhangbu Xu before the run started. My intuition before the run was that the beam related background would swamp this trigger unless more signals were required to be in coincidence with the East ZDC, but from what we've been able to determine so far it appears that this is not the case. My belief at this point is that this first trigger condition will contain essentially as large a fraction of the total d-Au hadronic cross section as we can hope to trigger on. The open question at this point is what the yield of events useful for analysis is with this trigger condition, once one puts on any vertex constraints (e.g. +- 25 cm in Z, etc.). For this information it is imperative that as soon as events start making it through the Software reconstruction chain that collaborators start looking at the data and providing us with feedback. Likely conduits for this feedback are through Working Group Convenors, through the Physics Analysis Coordinator (aka James Dunlop), or the Chair of the STAR Trigger Board (aka Jim Thomas).

 Condition #2 above, which I expect to be completely contained in the first trigger condition, has been demonstrated to give a very "pure" collision trigger. From Vernier Scans that have been at the STAR hall, and the relevant collider parameters (beam currents, emittances, etc.) the cross section for this ZDC coincidence condition looks to be ~0.4 b. As this trigger condition requires the single neutron in the deuteron to deposit at least 15 Gev of it's energy in the West ZDC, which has a very small acceptance, ~18 m from the IR and centered on zero degrees, there is reason to suspect that this trigger will have a strong bias towards peripheral d-Au collisions.Les Bland, Akio Ogawa, and the BBC and trigger groups have been working very hard to get all of the BBC detectors and electronics unctioning and in to the trigger. Les and Akio are currently studying the pulse height and timing information for the multiple BBC channels, and an estimate is that we'll be adding a BBC based component to our min-bias Run Configuration sometime next week. It's important to note that the data from the BBC detectors are in the data for all of the events we take. Again, it is expected that there will be a large overlap between the current ZDC based trigger conditions and those that we'll take with the BBC conditions. My expectation is that the yield of events that make it into people's analysis will be larger with the BBC based trigger conditions, but time will tell.The BEMC has been coming online very quickly. There was some concern going into the run that setting the timing, and then gains, for the BEMC could be slow process is the relatively low multiplicity d-Au environment. My personal view is that this is going quickly partly due to the higher multiplicity in these events than some of us expected, but is largely due to the fact that the BEMC electronics and HV systems are much more stable, and the controls for the system much improved over last year's experience. This system got to this state because of the extended effort put into testing and debugging the system by the BEMC group before this year's run started. The SVT hasn't been brought online yet, but should get into the run within a matter of days. After the extensive replumbing effort on the SVT cooling system during the shutdown, and the additional monitoring and control features added to the water system, it looks like the temperature stability of the system will be much better this year. There is also every expectation that the noise on the SVT will be very low, as was seen during last year's proton run after some modifications to the HV cabling by Dave Lynn and crew.My rough projection on what can be expected over the next few weeks is as follows. The TPC is ready to take Physics data now, and we'll start accumulating min bias events. Very soon (day or so) we'll get the final tuning of the FTPC done for taking physics data. With a few days, the BEMC towers will be ready to start taking Physics data (note that these detectors will for the most part be in the data stream as they get tuned up). Early to mid next week we'll have the BBC in our trigger mix. Starting sometime next week we'll start working to incorporate the BEMC information into test "High Pt" triggers. The DAQ and Run Control systems are up and running quite well, but it's in Tonko's and Jeff's natures to always tweak them to squeeze the optimum performance out of the system, so I expect this to continue. The trigger system is largely functional, but has some stability problems at present, as well as some further functionality that isn't implemented at present. I expect that the system will get more stable as the run progresses. Bringing STAR back to life is a daunting endeavor each time we prepare for a run, and there are times during the effort when the task seems right on the brink of becoming overwhelming, but as things are looking now, it appears that we have every reason to expect another successful STAR run, and another spectacular STAR data set.
 

Greetings from Long Island,Bill Christie
 

Persona Grata

        This month's persona grata is Tim Hallman,

      Interviewed by Eugene Yamamoto
 

STAR Software and Computing

        This month there is no contribution due to a delayed request for input.