# Upsilon Analysis in d+Au 2008

## Upsilon yield and nuclear modification factor in d+Au collisions at sqrt(s)=200 GeV.

PAs: Anthony Kesich, and Manuel Calderon de la Barca Sanchez.

- Dataset QA
- Trigger ID, runs

- Trigger ID = 210601
- ZDC East signal + BEMC HT at 18 (Et>4.3 GeV) + L2 Upsilon
- Total Sampled Luminosity: 32.66 nb^-1; 1.216 Mevents
- http://www.star.bnl.gov/protected/common/common2008/trigger2008/lum_pertriggerid_dau2008.txt

- Trigger ID = 210601
- Run by Run QA
- Integrated Luminosity estimate
- Systematic Uncertainty

- Trigger ID, runs
- Acceptance (Check with Kurt Hill)
- Raw pT, y distribution of Upsilon
- Accepted pT, y distribution of Upsilons
- Acceptance
- Raw pT, eta distribution of e+,e- daughters
- Accepted pT, eta distribution of e+,e- daughters
- Comparison plots between single-electron embedding, Upsilon embedding

- L0 Trigger
- DSM-ADC Distribution (data, i.e. mainly background)
- DSM-ADC Distribution (Embedding) For accepted Upsilons, before and after L0 trigger selection
- Systematic Uncertainty (Estimate of possible calibration and resolution systematic offsets).
- "highest electron/positron Et" distribution from embedding (Accepted Upsilons, before and after L0 trigger selection)

- L2 Trigger
- E1 Cluster Et distribution (data, i.e. mainly background)
- E1 Cluster Et distribution (embedding, L0 triggered, before and after all L2 trigger cuts)
- L2 pair opening angle (cos theta) data (i.e. mainly background)
- L2 pair opening angle (cos theta) embedding. Needs map of (phi,eta)_MC to (phi,eta)_L2 from single electron embedding. Then a map from r1=(phi,eta, R_emc) to r1=(x,y,z) so that one can do cos(theta^L2) = r1.dot(r2)/(r1.mag()*r2.mag()). Plot cos theta distribution for L0 triggered events, before and after all L2 trigger cuts. (Kurt)
- L2 pair invariant mass from data (i.e. mainly background)
- L2 pair invariant mass from embedding. Needs simulation as for cos(theta), so that one can do m^2 = 2 * E1 * E2 * (1 - cos(theta)) where E1 and E2 are the L2 cluster energies. Plot the invariant mass distribution fro L0 triggered events, before and after all L2 trigger cuts. (Check with Kurt)

- PID
- dE/dx
- dE/dx vs p for the Upsilon triggered data
- nsigma_dE/dx calibration of means and sigmas (done by C. Powell for his J/Psi work)
- Cut optimization (Maximization of electron effective signal)
- Final cuts for use in data analysis

- E/p
- E/p distributions for various p bins
- Study of E calibration and resolution between data and embedding (for L0 Trigger systematic uncertainty)
- Resolution and comparison with embedding (for cut efficiency estimation)

- dE/dx
- Yield extraction
- Invariant mass distributions
- Unlike-sign and Like-sign inv. mass
- Like-sign subtracted inv. mass
- Crystal-Ball shapes from embedding/simulation. Crystal-ball parameters to be used in fit

- Fit to Like-sign subtracted inv. mass, using CB, DY, b-bbar
- Contour plot (1sigma and 2sigma) of b-bbar cross section vs. DY cross section
- Upsilon yield estimation and stat. + fit error

- Invariant mass distributions
- Cross section calculation.
- Yield, dN/dy
- Integrated luminosity (for 1/N_events, where N_events were the total events sampled by the L0 trigger)
- Efficiency (Numbers for each state, and cross-section-branching-ratio-weighted average)
- Uncertainty
- pt Distribution (invariant, i.e. 1/N_event 1/2pi, 1/pt dN/dpt dy) in |y|<0.5 vs pt) This might need one to do the CB, DY, bbbar fit in pt bins.

- Nuclear Modification Factor
- Estimation of <Npart> for the dataset, and uncertainty.
- Putting it all together: dN/dy in dAu, Npart, Luminosity (N_events), divided by the pp numbers (dsigma/dy, sigma_pp)
- Plot of R_dAu vs y, comparison with theory
- Plot of R_dAu vs Npart, together with Au+Au
- Plot of R_dAu vs pt. Try to do together with Au+Au (minbias, maybe in centrality bins, but maybe not enough stats)

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