In the directory /work/halla/ndelta-2/databases are the following files.

1. The database optimizing beta, scint adc and vdc for runs
    1025 to 1765 is db_ndelta_1765_vdc_opt .
   This database also has the correct coefficients for the BPM
	determined by Zhengwei Chai

2. The database db_835_e_emily has electron arm delta 
    optimized by Emilie Penel for Dec 1999 12C elastic data.

3. The database db_ndelta_3.5  has electron theta,phi and ytgt
	and y000,t000, and p000 optimized by Nilanga.
   He started with the VCS 3.5 GeV database
   Optimized the t000,y000 and p000 using run 1760
   Then optimize the theta and phi using 1H data and sieve
     using a reduced number of elements in theta.
   The optimized the Y030 element . 
   For now the delta matrix is used unchanged.
   There are no T000 nor Y000 terms for electron optics in this database.

4. The database db_840_dp_h_rikki has hadron arm delta
    optimized by Rikki Roche for Dec 1999 12C elastic data.

5. The database db3500_e_zwchai is an improved
	version of db_ndelta_3.5 for electron arm optics.

6. The database db845_e_zwchai has the electron arm
	theta,phi and ytgt optimized using the Dec 1999 845 data.

7.  The database db845_h_zwchai has the hadron arm
	theta,phi and ytgt optimized using the Dec 1999 845 data.

8. The database  db700_1400_h_zwchai has the hadron arm
	the ytgt and y000,p000,t000 optimized using
	700MeV, 1.0GeV 1.3GeV ndelta pointing data 
	
9. The database db_ndelta_e4000_h840_nilanga has improved
	delta for electron and hadron. The electron D000,D100
	and D200 were changed to improve the resolution for
	12C and 3He(e,ep) data at 4 GeV. The hadron
10. After new collimator survey Zhengwei optimized the detector
     offsets. There are in db_ndelta_pd1_new_zwchai

11. The database db_ndelta_period1 has
    a) the beta,scint adc and vdc from db_ndelta_1765_vdc_opt
    b) the bpm coefficients from db_ndelta_1765_vdc_opt
    c) electron theta,phi and y from db3500_e_zwchai
    d) electron delta from db_ndelta_e4000_h840_nilanga
    e) hadron delta from db_ndelta_e4000_h840_nilanga
    f) hadron phi,theta from db845_h_zwchai
    g) hadron ytgt from db700_1400_h_zwchai
    h) t000,y000,p000 from db_ndelta_pd1_new_zwchai 
        for electron and hadron.

11. On 1/3/01, Nilanga did the determination of the gamma for 
the spectrometers using 800 MeV 12C elastics. I added the
gammas to db_ndelta_period1 .

When I calculate spectrometer constants for 89044 (12/99), ndelta (05/00) 
and 97111 (10/00) optics data, this is what I get

                89044   ndelta  97111
Gamma_e         270.2   270.2   270.3
Gamma_h         269.8   269.8   269.9

Each with an uncertainty of about 0.15

I used only the EP measurements for these, There is an ARC measurement for
the 89044 setting, and if I use that the numbers become 270.1 and 269.7
respectively.

So I think it is safe to use Gamma_e=270.2 +/- 0.15 and Gamma_h=269.8 +/-
0.15

In addition Nilanga looked at the dependence of gamma
on the central field by looking at the missing mass peak
in 12C(e,ep) inelastic for electron arm between 500 and
4000 MeV/c . He found a dependence starting around 2500 MeV/c
so 
Left:

0.0000E-01  2.702E+02  0.0000E-01  -1.57E-03

Right:

0.0000E-01  2.698E+02  0.0000E-01  -1.57E-03

These changes were added to the database db_ndelta_period1
So for example pcent (MeV/c) = 270.2*B - 1.57e-3*B^3 
where B is dipole field in kG. 


12.    Zhengwei determined ytgt from 700,1.0,1.3 data. Is this the
        best way to do it? Should we optimize at each.