RAWDAT - Which holds the raw event data (ADC values etc.) Certain
track subtypes point back to the relevant rawdata portion of this
block.
EVLST - Which contains event description information and pointers
to the track and vertex information in TRKLST. In particular the
TRKSUB and VRTSUB arrays are used to index the the track and
vertex entries . The counters TOTTKS and NVTX give the number of
track and vertex entries pointed to by TRKSUB and VRTSUB
respectively.
TRKLST - Which contains the track and vertex information blocks
(subtypes) in one large array.
For the exact contents of these commons please refer to the
source files with filetypes .INC in BES$LIBPAMS:[BESCDE]. Only
those parts relevant to this document are included . The
quantities of interest here are;
TOTTKS : total number of entries in the TRKSUB array.
This is the largest value of the 2-nd index
of the TRKSUB array for the event.
NVTX : number of vertices (15 max) in the event
This is the largest value of the 2-nd index
of the VRTSUB array for the event.
VRTSUB : pointers to ITRK where vertex lists are located
(a zero value indicates non-existent subtype)
TRKSUB : pointers to ITRK where track lists are located.(A
zero valued pointer indicates non-existent subtype)
The value in TRKSUB points to the TOP of the
record of interest so that ITRK(TRKSUB(n,trk)+1)
is the first word of subtype=n for track=trk.
(Also true for VRTSUB )
NXTSUB : Points to the last word filled in the TRK buffer.
(i.e. next free location is TRK(NXTSUB+1) )
TRK : large multi-purpose array which stores the
vertex and track lists, amoung other things.
The first 26 words of ITRK store the sizes of
arrays and lists, in the following order ;
Initial value of NXTSUB on each new event,
Number of words in /EVLST/ preceding vrtsub,
Dimension of VRTSUB (2 items),
Lengths of vertex subtype lists (8 items),
Dimension of TRKSUB (2 items),
Lengths of track subtype lists (12 items).
Notes:
The subtype 1 entry of a vertex or track entry must be
filled in order for that entity to be logged out. I.e.
unattached subtypes will be weeded out by EVLOG during data
logging.
The order of the VRTSUB and TRKSUB indices is subtype first,
track or vertex number second.
[top]
Item =TRK(VRTSUB(N,V) + J) .
J NAME CONTENTS
- ---- --------
1 NWDS number of words in this record
2 NCHRG number of charged prongs in this vertex
3 NNEU number of neutral prongs in this vertex
(total tracks in this vertex is N = NPRNG+NEU)
4 IVTYPE Normally 1. Set to 2 if TOF disagrees with
the ID made by VEEFND for sec tracks.
5 IVID ID of most probable decay
-1 = cant tell 0 = not made
1 = K zero, 2 = anti-lamda,
3 = lamda, 4 = gamma (conv at pipe)
5 = pi zero, 6 = eta
100 = D vertex (charged or neutral)
(if ambiguous, tens digit gives other choice)
6 IBACK index of backward (parent) vertex
7 INTRK track number of incoming track
8 NFORE number of forward vertex linkages
9-13 IFORE indices of foreward linking vertices
13+1 ITK track numbers for this vertex (outward tks.)
. . "
. . "
13+NPRNG . "
. . "
13+NPRNG+NEU "
[top]
J NAME CONTENTS
- ---- --------
1 NWDS number of words in this record
2 VFIT method : 0=simple averages, large fid vol
1=fit for min dist, large fid vol
2=simple averages, small fid vol
3=fit for min dist, small fid vol
3 QTOT total charge of the prongs
4 RXY Perp distance from origin (0,0) to vertex .
5 X x (m) of vertex
6 Y y (m) of vertex
7 Z z (m) of vertex
8 DX error in x (m)
9 DY error in y (m)
10 DZ error in z (m)
11 CHI2 total chi sq for vertex fit (-1.0 if failed)
12 NDOF degrees of freedom
13 NTRK The number of tracks used in crude fit.
13+1 TRK List of the charged tracks used in this
+2 " vertex fit.
. " .
. .
13+NTRKS
Note: This subtype is filled for Vee's as well as the primary vertex.
J NAME CONTENTS
- ---- --------
1 NWDS Number of words in record
2 VFIT Fit type
(0 = simple ; 1 = good )
3 QTOT Total charge of the prongs
4 RXY Perpendicular distance (x-y) from vertex to
nominal beam location (XYZIR(1-2) in /RUNPRM/ )
5 X X (m) of vertex
6 Y Y (m) of vertex
7 Z Z (m) of vertex
8 DX Error in X (m)
9 DY Error in Y (m)
10 DZ Error in Z (m)
11 CHI2 Total ChiSq for vertex fit
(set to -1. if fit failed)
12 NDOF Degrees of freedom (REAL)
13 CHI2V ChiSq contribution from X,Y,Z
13+1 CHIOFF ChiSq contributions from
. . individual tracks
. . "
. . "
13+NCHRG+NNEU "
[top]
J NAME CONTENTS
- ---- --------
1 NWDS Number of words in this record
2 ACOLL Acollinearity angle (radians)
3 ACOPL Acoplanarity angle (radians)
(ACOLL,ACOPL = 0. ,if back to back)
4 LCOLL True if acollinear and xyz's match
5 LCOPL True if acoplaner and xyz's match
[top]
J NAME CONTENTS
- ---- --------
1 NWDS Number of words this record
2 MFSEC Method of finding secondary vertex
1=veefnd, 2=pizero, 3=kink
3 MASSO Mass calculated from tracks at origin
4 MASSV Mass calculated at sec vertex point
5 COS12 Cos of angle between vee tracks
6 COSRP Cos of angle between neutral decayer and
direction of secondary momentum vector
7 P Total momentum of secondary tracks
8 PX " x-mentum " " "
9 PY " y " " " "
10 PZ " z " " " "
11 ZDIFF Z difference at XY point of secondary.
12 E Total energy of secondaries
13 CHI2 Chi square of fit (=-1.0 if fit failed)
14 NDOF Degrees of freedom
[top]
J NAME CONTENTS
- ---- --------
1 NWDS Number of words in this record
2 NDTRKS Number of decay products in the D tag
3 ITAG Code for the D decay mode
ITAG decay mode
---- ----- ----
1 K- pi+
2 K- pi+ pi+
3 K- pi+ pi+ pi-
4 K0 pi+
5 K0 pi+ pi-
6 K0 pi+ pi+ pi-
7 K- pi+ pi0
8 K- pi+ pi+ pi0
9 K0 pi0
10 K0 pi+ pi0
11 K+ K-
12 K+ K- pi+
13 K+ K- pi+ pi-
14 pi+ pi-
15 pi+ pi+ pi-
16 K+ K0
17 K+ K0 pi-
18 pi+ pi0
4 ICHRG Charge of the D
5 MASS D final state invariant mass
6 BCMASS Beam-constrained mass of the D
7 PX Px of the D
8 PY Py of the D
9 PZ Pz of the D
10 P Total momentum of the D
11 E Total energy of the D
12+13 ITKMAP A double word bit map indicating track
numbers used in the TAG. Track # 1
corresponds to the LSB (20) of the first
word.
13+1 IDTRK Packed word for each of the decay
. products of the D. Format is:
.
. BYTE4 BYTE3 BYTE2 BYTE1
. +-----------------------------------+
. | | | | |
. | DKTRK1 | DKTRK2 | TRK# | TRKID |
. | | | | |
. +-----------------------------------+
.
. where...
.
. TRKID = particle type for the decay
. product
.
. 1 = chg pi
. 2 = chg K
. 4 = pi0
. 8 = K0
.
. TRK# = BES track number assigned
. to this particle. (virtual
. track in the case of pi0 or K0)
.
. DKTRK1(2) = BES track numbers of the
. the gammas from a pi0 or
. the pions from a K0.
13+NDTRKS (only filled when TRKID=4,8)
[top]
Item = TRK(TRKSUB(N,T) + J)
J Name Contents
- ---- --------
1 NWDS number of words in this record
2 ID track identifier:
0 = no identification made
1 = gamma
2 = electron
3 = muon
4 = pi
5 = K
6 = P
7 = LAMDA,
8 = ANTI-LAMDA
10 = ETA
≤ 0 = external track (e.g. backscatter)
3 IDUSED Bit mask indicating data used in particle
identification. The bit positions are encoded
as follows ;
mask Data type
---- ---- ----
x'01' TOF
x'02' dE/dx
x'04' Muon tubes
x'08' Shower counter
4 ICHRG charge 0, +1, -1 (9 if cant tell sign)
5 ITYPE A bit mask indicating the track type.
the systems are encoded as follows ;
mask System
---- ------
x'01' Drift Chamber
x'02' Barrel shower counter
x'04' DC SC data fitted simulaneously
-
x'08' Virtual (reconstructed) track
x'10' Hardware track info
x'20' TOF info
x'40' Muon tubes
x'80' End cap shower counter
6 MISS Bit mask indicating information lacking due to
geometry. The systems are encoded as follows;
mask System
---- ------
x'01' TOF
x'02' Drift Chamber
x'04' Shower chamber
x'08' Muon tubes
(It WOULD be too much to expect they'd be
the same as any of the above....)
7 IFROM vertex # from which this track originates
8 IDCAY vertex number that this track
decays to (0 if none)
[top]
J Type Name CONTENTS
- ---- ---- --------
1 I NWDS number of words this record
2 I ICHRG charge of track, +1, -1
3 R PXY at min. dist. of approach to beam origin
4 R PX "
5 R PY " (note that PZ/P gives cos(THETA),
6 R PZ " PXY/P gives sin(THETA),
7 R P " PX/PXY gives cos(PHI),
8 R THETA " PY/PXY gives sin(PHI)
9 R PHI " so use ratios rather than sin/cos
10 R X " to save cpu time )
11 R Y "
12 R Z "
13 R R "
14 I MFIT Fit method:
0 = circle fit
2 = ARCS fit
15 I NHIT Number of drift chamber hits in the fit
16 I NUSED Not used
17 R CHI2 Chi square from single track fit
18 I NDOF Degrees of freedom
19 R RMS Rms error of fit (ideally 1.0)
19+1 R ER Error matrix for good fit, triangular form
. . in coordinate : PHI,K=1/PXY,S=TAN(LAMBDA),
. . KSI,ETA(does not contain scattering error)
. . from pipe)
. . .
19+15 R . .
35 R EXTRP Distance from origin to first reconstructed
layer
36 R PATHL Total length of scattered track in measurement
region
37 I IWPLAN Bit map (bits 0-32) of DC layers used AFTER
fit
38 I IWPLA1 Bit map (bits 33-40) of DC layers used AFTER
fit
39 I IVCHIT Bit map (bits 0-39) of DC layers used in fit
40 I IVCHI1
40+1 I IHIT(1) Predicted cell hit in Radial Layer 1
40+2 I IHIT(2) Predicetd cell hit in Radial Layer 2
. .
. . (one word for each of 40 radial wires)
. .
40+40 I IHIT(40) Predicted cell hit in last radial wire
(=80)
[top]
J NAME CONTENTS
- ---- --------
1 NWDS number of words in this record
2:18 Barrel TOF Items
2 AIT azmuthal counter number from projected
track fit ( 1.0LE AIT LE 49.0 )
3 IT counter number (1-48, 0 if no hit)
4 TOF time of flight (nsec)
5 BETA beta of track
6 ZTDC z (m) from TDC information
7 PH corrected pulse height
8 QUAL TOF quality (1.0=good trk; .LE.2.0=usable)
0.0 if ZT-ZTDC didnt match
2.0 if double hit in counter
3.0 if no hit in counter
4.0 all wts are zero;otherwise TQUAL=1.0
5.0 all wts are zero;otherw.TQUAL=0,2
6.0 if neutral track with good hit
7.0 if more than 2 hits per counter
8.0 missed one tdc (early cosmic)
9.0 if double hit in counter with bad
match with ZTDC (partner of track
with TQUAL=2.0) means effectively
a lower limit on TOF value
16.0 if neutral track with hit at one end
9 WTPI weight for PI
10 WTK " " K
11 WTP " " P
12 WTEPI " " e for e-pi hypothesis
13 MASS2 square of mass (gev)2 from TOF and P
14 PATH flight path length (m)
15 TOFERR estimate of error on TOF (nsec)
16 LINK Link to track hitting same counter.
These links form a closed loop.
17 LADJAB Link to track on adjacent counter (above).
18 LADJBE Link to track on adjacent counter (below).
19:35 Endcap TOF Items
19 AIT azmuthal counter number from projected
track fit
20 IT counter number (49-96, 0 if no hit)
21 TOF time of flight (nsec)
22 BETA beta of track
23 ZTDC z (m) from TDC information
24 PH corrected pulse height
25 QUAL TOF quality (1.0=good trk; .LE.2.0=usable)
0.0 if ZT-ZTDC didnt match
2.0 if double hit in counter
3.0 if no hit in counter
4.0 all wts are zero;otherwise TQUAL=1.0
5.0 all wts are zero;otherw.TQUAL=0,2
6.0 if neutral track with good hit
7.0 if more than 2 hits per counter
8.0 missed one tdc (early cosmic)
9.0 if double hit in counter with bad
match with ZTDC (partner of track
with TQUAL=2.0) means effectively
a lower limit on TOF value
16.0 if neutral track with hit at one end
26 WTPI weight for PI
27 WTK " " K
28 WTP " " P
29 WTEPI " " e for e-pi hypothesis
30 MASS2 square of mass (gev)2 from TOF and P
31 PATH flight path length (m)
32 TOFERR estimate of error on TOF (nsec)
33 LINK Link to track hitting same counter.
These links form a closed loop.
34 LADJAB Link to track on adjacent counter (above).
35 LADJBE Link to track on adjacent counter (below).
[top]
J NAME IorR CONTENTS
- ---- ---- --------
1 F NWDS I number of words this record
2 F NHIT I number of shower counter cell hits
3 F NPHIT I number of shower counter paired hits
4 F X1 R shower coords at first layer hit
5 DX1 R shower coords error at first layer hit
6 F Y1 R ..
7 DY1 R ..
8 F Z1 R ..
9 DZ1 R ..
10 F THETA R shower counter theta angle
11 DTHETA R shower counter theta angle error
12 F PHI R shower counter phi angle
13 DPHI R shower counter phi angle error
14 F E R total energy observed in SC (GEV)
-- No calibration done, same as ERAW
for the current version
15 DE R total energy error in SC (GEV)
16 F CHI1 R quality of SC fit, CHI2 TYPE 1
17 F CHI2 R quality of SC fit, CHI2 TYPE 2
18 F STAT R cluster status/link
19 F FLAG I shower counter fit flag
20 F MOD I module number for this track
(1 - barrel, 2 - E endcap, 3 - W endcap)
21 F CHIID R CHI SQ of identification
22 F ID R 1 = photon (SC particle identification)
1 = electron
2 = mu or min. ionizing
3 = hadron or fake photon
4 = e-h ambiguity or photon fake
ambiguity
-1 = didn't make cuts for photon
fake ambiguity
23 WTPH R weight for PHOTON
24 WTE R weight for ELECTRON
25 WTMU R weight for MU or MIN. IONIZING
26 WTHA R weight for HADRON
27 F COSX R -| direction cosines
28 F COSY R |==> from
29 F COSZ R -| track fit
30 F ERAW R total raw energy (sum of PHs 0.01)
31 F NBLK I number of layer blocks to follow
32 F NBLK+LAYL I first layer number
33 F NBLK+HITL I number of hit cells in this layer
34 F NBLK+EL R energy deposited in this layer (GeV)
35 F NBLK+PHIL R average PHI/X for this layer
36 F NBLK+DPHL R PHI/X RMS for this layer
37 F NBLK+ZL R average Z/Y (M) for this layer
38 F NBLK+DZL R Z/Y RMS for this layer
NB: A "" in these last four quantities indicates the
different interpetation for barrel vs endcaps
.
. in similar fashion for next layer block
.
[top]
J NAME CONTENTS
- ---- --------
1 NWDS number of words in this block
( = 6 + 14MULEVP )
2 ID muon identifier: 0 = not a mu
1 = mu
2 = cant tell
3 STAT Status bits on:
1-3 if hit within SIGVCT s.d. in V and
within SIGZCT s.d. in Z
4-6 if hit had ambiguous Z-pairing
7-9 if g.e.2 tubes hit
10-12 if no Z due to overflows
13-15 if no Z due to 2 trks in same mod
16-18 if no Z due to Z calib problems
19-21 if no Z due to no ganged hit
22-24 if no Z info for track
4 LEVR number of layers "required" for a muon
i.e. the number of layers in which
a muon would have to scatter by more
than 3 s.d. in position or momentum
to avoid being detected
5 LEVE number of layers "expected" for a muon
i.e. the number of layers in which
a mu is expected but could miss being
detected by any amount of scattering
MULEVE > or = MULEVR
6 LEVP number of layers "possible" for a muon
i.e. the number of layers a muon could
reach by scattering L.E. than 3 s.d.
MULEVP > or = MULEVE
Oi= 6+(i-1)14 Offset pointer for layer=i
Oi + 1 OCTANT octant number for layer=i (0-7)
Oi + 2 DELSTR number of s. d. from ranging
out due to strag
Oi + 3 XPROJ projected x in level=i
Oi + 4 YPROJ " y " " "
Oi + 5 ZPROJ " z " " "
Oi + 6 DVNORM normalized residual in v-plane
Oi + 7 PPROJ projected momentum
Oi + 8 XMUL expected sigma in position
Oi + 9 SIGSTR " " " STRAGGLING
Oi +10 XHIT x co-ordinate of closest muon hit
Oi +11 YHIT y " " " " "
Oi +12 ZHIT Z " " " " "
Oi +13 DELPOS number of s. d. between projected
track and closest hit
Oi +14 GRMST equivalent grams of iron traversed
[top]
J type Name Contents
- ---- ---- --------
1 I NWDS number words this record
2 I NDEDX no. of good dE/dx hits (ex. overflows)
3 I NTOT no. of good dE/dx hits (inc. overflows)
4 I TRBL flag indicating any problems in dE/dx
analysis:
TROUBL meaning
0 no info (NTOT=0)
1 AOK
2 more overflows than truncated
points. PHMP represents a
minimum value. ID attempts to
take this situation into
account properly.
5 RES1 Reserved for future use
6 RES2 Reserved for future use
7 I ID Particle type from dE/dx fit
ID meaning
Note: "definitness" 0 inconclusive (error or tail)
in the ID of a particle 1 definite e
is based on roughly a 95% 2 " mu
decision (skew cuts). e.g. 3 e/mu
a track within 95% prob. 4 definite pi
for a pion and outside of 5 e/pi
95% prob. for all other 6 mu/pi
particles is called a 7 e/mu/pi
definite pion. 8 definite K
One may notice ID is 9 e/K
simply a 5-bit integer 10 mu/K
with a bit turned on 11 e/mu/K
for each particle 12 pi/K
hypothesis satisfied: 13 e/pi/K
14 mu/pi/K
Mask particle 15 e/mu/pi/K
---- --------
x'01' e 16 definite p
x'02' mu 17 e/p
x'04' pi 18 mu/p
x'08' K 19 e/mu/p
x'10' p 20 pi/p
21 e/pi/p
22 mu/pi/p
23 e/mu/pi/p
24 K/p
25 e/K/p
26 mu/K/p
27 e/mu/K/p
28 pi/K/p
29 e/pi/K/p
30 mu/pi/K/p
31 inconclusive
(big sigma or
high momentum)
8 R PHMP most probable pulse height from
truncated mean
9 R DPHMP fractional uncertainty (sigma) on
measured pulse height
10 R PHMIP average pulse height for min-I
11 R PHRC1 run correction for pulse heights
12 PHRC2 "
13 PHRC3 "
14 PHRC4 "
Note:Following items 15:19 are
signed values !
15 R XSE # of sigma from e
16 R XSMU " " " mu
17 R XSPI " " " pi
18 R XSK " " " K
19 R XSP " " " p
19+1 NF I XTAG(J) status of hit in wire layer J
. (j=1 to 40)
19+j
. XTAG meaning
. 1 good hit
. 2 overflow
. 3 no mtac hit
4 predict > 1 track in cell
. 5 multiple mtac hits
. 6 mtac but no dedx
. 7 bad wire
. 8 corrected ph is < 0.
. 9 outside good time window
19+40
59+1 R PH(J) corrected pulse height for signal
. from wire layer J. Filled when
59+j XTAG(J) < 3.
.
.
59+40
99+1 R PHRAW(J) raw pulse height for signal from
. wire layer J. Filled when XTAG(J) < 3
99+j
.
.
99+40
[top]
J NAME CONTENTS
- ---- --------
1 NWDS number words this record
2 ICHRG charge of track +1, -1, 0
3 PXY PXY at location of vertex
4 PX PX " " " "
5 PY PY " " " "
6 PZ PZ " " " "
7 P P " " " "
8 THETA THET "(see note in subtype 3 for this)
9 PHI PHI " " " " " " " "
10 X X " " " "
11 Y Y " " " "
12 Z Z " " " "
13 RXY R in XY plane
(not filled for secondary vertices )
14 MFIT Fit method: 0 = circle fit
1 = good one track fit
15 NDCH Number of dc hits in the fit
16 spare Reserved - added to make this format the same
as Subtype 3 above.
17 CHI2 Chi square from single track fit
18 NDOF Degrees of freedom
19 RMS RMS error of fit
19+1 ERR Error matrix (in phi, 1/pxy, s)
. ( diagonal element = 999. and
. off-diagonal = 0. for fits with
19+6 VFIT .le.1 . )
26 DPX Error PX
27 DPY Error PY
28 DPZ Error PZ
[top]
J NAME CONTENTS
- ---- --------
1 NWDS number words this record (3+NDCH)
2 NDCP number of dc pointers to follow
3 IDCH bits 20-31: residual in 10 micron units
18-19: unused
16-17: wire side assigned
. . 1=+, 2=-, 3 don't care
. . 0-15: pointer to IRAW
. . e.g. for M'th dc hit in track ITK, let
IP=IBITS(ITRK(TRKSUB(9,ITK)+2+M),0,16)
. . then IRAW(IP) contains tag word/mtac valueT
. .
NWDS Spare
[top]
J NAME CONTENTS
- ---- --------
1 NWDS Number words this record
= # of SC hits 2 + 1
2 HITRAW Raw data of the first hit
3 HITFLG Status flag of the first hit
4 HITRAW
5 HITFLG
:
:
Meaning of HITRAW
31 15 0 : bit
________
| PNT2 | PNT1 |
|____|____|
BARREL :
PNT1 = pointer to east end of wire
PNT2 = pointer to west end of wire
ENDCAP :
PNT1 = pointer to top end of wire
PNT2 = pointer to bottom end of wire
For meanings of HITFLG, refer to HITLST.INC
[top]
Following format for PROJECTIONS (IVDCAY=0)
--------- ------ --- ----------- ----------
J NAME CONTENTS
- ---- --------
1 NWDS number words this record
2 XBT coords at barrel TOF radius
3 YBT " " " "
4 ZBT " " " "
5 THETABT direction of track at XT,YT,ZT
6 PHIBT " " " "
7 PBT P at XT,YT,ZT
8 XSC coords at barrel SC entrance
9 YSC " " " "
10 ZSC " " " "
11 THETASC direction of track at XSC,YSC,ZSC
12 PHISC " " " "
13 PSC P at XSC,YSC,ZSC
14 XET coords at end cap TOF plane
15 YET " " " " "
16 ZET " " " " "
17 THETAET direction of track at XET,YET,ZET
18 PHIET " " " " "
19 PEC P at XET,YET,ZET
20 XEC coords at end cap SC entrance
21 YEC " " " " "
22 ZEC " " " " "
23 THETAEC direction of track at XEC,YEC,ZEC
24 PHIEC " " " " "
25 PEC P at XEC,YEC,ZEC
26 XC coords at coil radius
27 YC " " " "
28 ZC " " " "
29 THETAC direction of track at XZ,YC,ZC
30 PHIC " " " "
31 PC P at XC,YC,ZC
32 BTPATH path length from XM,YM to XBT,YBT
33 ETPATH path length from XM,YM to XET,YET
Following format is used to specify DECAY points (IVDCAY ne 0)
--------- ------ -- ---- -- ------- ----- ------ ------- -- --
2 IDCHR charge 0, +1, -1 (9 if sign unknown)
3 PXYDY at xdcy,ydcy,zdcy
4 PXDY " "
5 PYDY " "
6 PZDY " "
7 PDY " "
8 THETADY " "
9 PHIDY " "
10 XDY coords of decaying track near decay vertex
11 YDY " " " " " " "
12 ZDY " " " " " " "
13 DYLEN 3-D path length of decaying particle
(from parent vtx to decay vtx)
13+ 1 ERRDY error matrix at decay point on track
. . "
13+15 . "
[top]
J NAME CONTENTS
- ---- --------
1 NWDS number of words this record
2 ICHRG charge of track, 0, +1, -1
3 PXY at secondary vertex (starting point coords)
4 PX "
5 PY " (note that PZ/P gives cos(THETA),
6 PZ " PXY/P gives sin(THETA),
7 P " PX/PXY gives cos(PHI),
8 THETA " PY/PXY gives sin(PHI)
..or TANLAM (for new tracking code)
9 PHI " so use ratios rather than sin/cos
10 X " to save cpu time).
11 Y "
12 Z " <=ZDY-(XY path from IR>cot(THETA))
13 RXY " (in XY plane)
14 MFIT fit method
1=VEEFND, 2=PIZERO
15 MASS mass of particle
16 ITYPE type of fit
17 CHI2 chisq of fit
18 NDOF degrees of freedom for fit
[top]