1. Y. Akiba (RIKEN/RBRC) 2016/04/21 Radiation lab meeting
RUN16 Status
Y. Akiba (RIKEN/RBRC)
2016/04/21
Radiation lab meeting

2. Au+Au recorded luminosity
PHENIX BUP goal: 1.8/nb
RHIC is down due to a magnet problem for 20d
PHENIX will reach the BUP goal in a few days

3. RHIC down time 3/18-4/6
RHIC was down due to a manget problem from 3/18 to 4/6
The problem was caused by a quench protection diode. For repair, the diode needed to be replaced
CA-D this that the problem is caused by excessive radiation dose to the diode
2 of 12 sectors of RHIC was warmed up; the diode was replaced; and RHIC was cooled down again
RHIC was recovered and physics re-started on 4/6.
RHIC was down for 20 days due to the problem.

4. Extension of RUN16
In Machine/Detector meeting on 4/12, extension of RUN16 and when the d+Au run will start was discussed
PHENIX has ben requesting 5 physics weeks of d+Au BES for 4 energy points (200, 62, 39, 20 GeV) for flow measurement in central d+Au and direct photon measurement with MPC-EX (200 GeV only).
STAR has been requesting for more AuAu run for heavy flavor measurement with HFT
Thomas Roser said they can commit 2 weeks of extension from the power saving during the shutdown and the lower electricity cost. He indicated that 1 more week of extension is likely, but he need to see the power bill of March to determine if it is possible to do so or not.
Berndt decided to extend the run by 2weeks. He also extend the AuAu run to May 7th. This gives 10 physics weeks for Au+Au as PAC recommended

5. Calendar With 2 weeks extension: AuAu to 5/7. d+Au to 6/10 CeC test
Run ends 6/21
With 1 more week of extension:
Run ends 6/28
Coherent electron Cooling (CeC) test
(important R&D for eRHIC)

6. d+Au BES: charge from ALD (1)
RHIC run was extended by 2 weeks. This allows 5 calendar week of d+Au BES.
Thomas Roser indicated that 1 additional week of extension was “likely” but not certain.
We need 6.5 calendar weeks for our d+Au BES program of 4 energy points (200,62,39,20 GeV).
Berndt Mueller asked PHENIX to present our plan for
5 calendar weeks and 6 calendar weeks of dAu BES
by early next week.
RHIC run plan will be discussed again in the Machine/Experiment meeting on 4/26. By the time we ill know if 1 more week of extension is possible or not.

7. Projections (based on SONIC) for 5 weeks BES
0-5% central events within |zvtx|< 10 cm
1 week, 1.6 B evts
1 week, 160 M evts
1.5 weeks, 110M
1.5 weeks, 9M
robust baseline
v2 and v3
measurements
All 3 lower energies for robust v2 measurements to establish
role of pre-equilibrium stage
role of hadronic stage
Factor of ~20 stat increase from Run8
FVTX improved EP
v3 at lower energy:
more sensitive to time spent in QGP
Does v3 collapse at lower energy ?
upper limits of v3 can be established
same detector conditions=>
systematics control in the BES
Statistically significant measurements for both v2 and v3
Transition region for v3 collapse
Largest lever arm for v2 measurements

8. Run15 p+Au vs Run16 d+Au
RUN15 BUP projection
RUN16 projection
Expected results from 1 week of d+Au is similar to p+Au projection in Run15 BUP
Bonus: centrality dependence in d+Au

9. d+Au BES: charge from ALD (2)
I asked to discuss the ALD charge in a joint session of PLHF/HHJ PWG on 4/14.
We decided the priority and plan for 5 and 6 weeks of dAu BES
The plan (next slide) was submitted to Berndt Mueller on 4/19.
This will be discussed in the next Machine/Detector meeting on 4/26, and RUN16 plan (length of RUN and

10. PHENIX plan of 5 and 6 weeks of dAu
This is part of my message I sent to Berndt. The message was also forwarded to phenix-p-l.

11. event alignment of VTX pixel
In RUN16, a timing problem of pixel was discovered.
About 30 % of pixel chips in B0 can lost event synchronization with the rest of PHENIX
This appears to be a problem in multi-event buffer in those chips
We found we had the same problem in RUN15 and RUN14.
The problem can be fixed by offline. We are developing codes to fix the problem.
The code will be applied during DST production
Good
1 event shift
2 event shift
3 event shift
Correlation of # of hits in a pixel chip and BBC charge with different “event shift”
If correlation is high, the chip is in synch with BBC.
The plot clearly show that this chip has event synchronization problem

12. Summary PHENIX will reach BUP goal of AuAu in a few days
RHIC had 20 days of down time due to a magnet problem. The problem was repaired and RHIC is running again.
RUN16 was extended by 2 weeks; 1 more week of extension is “likely”
PHENIX submitted run plan/request for d+Au BES
The length of d+Au BES (now 5 weeks) and extension of 1 more week will be discussed on 4/26.