# Presentation: 902810

## AGS pp Status

## AGS and Booster Lattices  

- The vertical tunes are as high as in run6 for strong intrinsic resonances for both users.
- sin9v has been raised high at 36+.
-  y at 0+ as high as 8.98
- Booster harmonics seem OK (scan done at injection).
- Injection-on-the-fly lattice: the ramp speed at G=5 is about 3 times faster.

## AGS Vertical Tune along Ramp

**AGS Vertical Tune along Ramp**

- Right now it is 8.98 at 0+nu

## Emittance with Injection-on-the-Fly  

- The injection-on-the-fly seems to have larger aperture at injection, since the emittance blow up as indicated by jump target study did not cause much beam loss.
- On the other hand, it is clear from the jump target study (scraping beam after transition) that there is  emittance growth correlated with intensity increase: we could not generate a bright beam. There is emittance growth early in the cycle.  A down ramp emittance measurement also points to the early part of the cycle for the growth.  BtA match study is not conclusive but no big mis-match observed there. All of these hint that it could be due to either space charge or instability near injection.
-   The beam emittance (rf off at flattop) are different now from run6:
-                Now        H 16,  V 13     with 1.3*1011            5/11/06   H 11.4 V 16    with 1.6*1011            5/12/06   H 10.4 V 15.2 with 1.36*1011 The larger horizontal emittance is likely one factor of stronger polarization profile observed in the AGS.

##  Polarization  of AGS Injection-on-the-Fly  

- The injection measurements with e880 polarimeter (last Tuesday) indicate there is polarization loss before or right at AGS injection. The asymmetries are 59-60 vs. 64 in run6. We have a relative 7% difference. We will recheck it.
-  Two horizontal polarization profiles taken shown a stronger profiles than the ones in run6.
-  The intensity scan with chopper width shows a step in polarization vs. emittance.
-  The larger horizontal emittance is likely one factor of stronger polarization profile observed in the AGS.
-  Polarization level drifted from high 50s down to low 50s with similar intensity.
- Possible problems:
- harmonics around 36+ keeps drifting.
- hybrid resonance 60-9-x which is affected by both horizontal emittance and vertical harmonics (Thomas). Will look at it.

## AGS Intensity Scan

## User2 setup  

- Similar polarization as user4.  A shallower polarization profile is expected. We will measure it as soon as tonight.
- Horizontal emittance smaller. H:V (11,15).
- There are still two differences besides the tiny difference of vertical tunes: BtA and injection emittances are larger now; no gamma_t quads on around transition.
- Extraction to RHIC has been setup at this point.
- Bunch length is more flexible. It is 32ns currently for both user2 and user4.

## Plan  

- Set up run6 lattice in AGS user2. Check polarization and emittances. First attempt to inject RHIC with user2.
- Injection-on-the-fly: We will increase the AGS injection energy to quantify the effect of the emittance growth.
- Jump target study with user2 and user4 (higher injection energy).
- Vertical and horizontal polarization profile measurements.
- BtA match study for both users.