Logo ROOT   6.10/02
Reference Guide
Namespaces
zdemo.py File Reference
Tutorials » PyRoot tutorials

Namespaces

 zdemo
 

Detailed Description

This macro is an example of graphs in log scales with annotations.

The presented results are predictions of invariant cross-section of Direct Photons produced at RHIC energies, based on the universality of scaling function H(z).

These Figures were published in JINR preprint E2-98-64, Dubna, 1998 and submitted to CPC.

pict1_zdemo.py.png
1 
2 import ROOT
3 from array import array
4 
5 NMAX = 20
6 Z = array( 'f', [0.]*NMAX )
7 HZ = array( 'f', [0.]*NMAX )
8 PT = array( 'f', [0.]*NMAX )
9 INVSIG = array( 'f', [0.]*NMAX )
10 
11 NLOOP = 0
12 saves = {}
13 
14 #_______________________________________________________________________________
15 def hz_calc( ENERG, DENS, TGRAD, PTMIN, PTMAX, DELP ):
16  from math import sin, cos, sqrt
17  global NLOOP
18  global Z, HZ, PT, INVSIG
19 
20  CSEFT= 1.
21  GM1 = 0.00001
22  GM2 = 0.00001
23  A1 = 1.
24  A2 = 1.
25  ALX = 2.
26  BETA = 1.
27  KF1 = 8.E-7
28  KF2 = 5.215
29 
30  MN = 0.9383
31  DEGRAD=0.01745329
32 
33  # print 'ENR= %f DENS= %f PTMIN= %f PTMAX= %f DELP= %f ' % (ENERG,DENS,PTMIN,PTMAX,DELP)
34 
35  DNDETA= DENS
36  MB1 = MN*A1
37  MB2 = MN*A2
38  EB1 = ENERG/2.*A1
39  EB2 = ENERG/2.*A2
40  M1 = GM1
41  M2 = GM2
42  THET = TGRAD*DEGRAD
43  NLOOP = int((PTMAX-PTMIN)/DELP)
44 
45  for I in range(NLOOP):
46  PT[I]=PTMIN+I*DELP
47  PTOT = PT[I]/sin(THET)
48 
49  ETOT = sqrt(M1*M1 + PTOT*PTOT)
50  PB1 = sqrt(EB1*EB1 - MB1*MB1)
51  PB2 = sqrt(EB2*EB2 - MB2*MB2)
52  P2P3 = EB2*ETOT+PB2*PTOT*cos(THET)
53  P1P2 = EB2*EB1+PB2*PB1
54  P1P3 = EB1*ETOT-PB1*PTOT*cos(THET)
55 
56  X1 = P2P3/P1P2
57  X2 = P1P3/P1P2
58  Y1 = X1+sqrt(X1*X2*(1.-X1)/(1.-X2))
59  Y2 = X2+sqrt(X1*X2*(1.-X2)/(1.-X1))
60 
61  S = (MB1*MB1)+2.*P1P2+(MB2*MB2)
62  SMIN = 4.*((MB1*MB1)*(X1*X1) +2.*X1*X2*P1P2+(MB2*MB2)*(X2*X2))
63  SX1 = 4.*( 2*(MB1*MB1)*X1+2*X2*P1P2)
64  SX2 = 4.*( 2*(MB2*MB2)*X2+2*X1*P1P2)
65  SX1X2= 4.*(2*P1P2)
66  DELM = pow((1.-Y1)*(1.-Y2),ALX)
67 
68  Z[I] = sqrt(SMIN)/DELM/pow(DNDETA,BETA)
69 
70  Y1X1 = 1. +X2*(1-2.*X1)/(2.*(Y1-X1)*(1.-X2))
71  Y1X2 = X1*(1-X1)/(2.*(Y1-X1)*(1.-X2)*(1.-X2))
72  Y2X1 = X2*(1-X2)/(2.*(Y2-X2)*(1.-X1)*(1.-X1))
73  Y2X2 = 1. +X1*(1-2.*X2)/(2.*(Y2-X2)*(1.-X1))
74  Y2X1X2= Y2X1*( (1.-2.*X2)/(X2*(1-X2)) -( Y2X2-1.)/(Y2-X2))
75  Y1X1X2= Y1X2*( (1.-2.*X1)/(X1*(1-X1)) -( Y1X1-1.)/(Y1-X1))
76 
77  KX1=-DELM*(Y1X1*ALX/(1.-Y1) + Y2X1*ALX/(1.-Y2))
78  KX2=-DELM*(Y2X2*ALX/(1.-Y2) + Y1X2*ALX/(1.-Y1))
79  ZX1=Z[I]*(SX1/(2.*SMIN)-KX1/DELM)
80  ZX2=Z[I]*(SX2/(2.*SMIN)-KX2/DELM)
81 
82  H1=ZX1*ZX2
83 
84  HZ[I]=KF1/pow(Z[I],KF2)
85  INVSIG[I]=(HZ[I]*H1*16.)/S
86 
87 
88 #_______________________________________________________________________________
89 def zdemo():
90  from array import array
91  global NLOOP
92  global Z, HZ, PT, INVSIG
93  global saves
94  global hz_calc
95 
96  # Create a new canvas.
97  c1 = ROOT.TCanvas( 'zdemo', 'Monte Carlo Study of Z scaling', 10, 40, 800, 600 )
98  c1.Range( 0, 0, 25, 18 )
99  c1.SetFillColor( 40 )
100  saves[ 'c1' ] = c1 # prevent deteletion at end of zdemo
101 
102  pl = ROOT.TPaveLabel( 1, 16.3, 24, 17.5,
103  'Z-scaling of Direct Photon Productions in pp Collisions at RHIC Energies', 'br' )
104  pl.SetFillColor(18)
105  pl.SetTextFont(32)
106  pl.SetTextColor(49)
107  pl.Draw()
108  saves[ 'pl' ] = pl
109 
110  t = ROOT.TLatex()
111  t.SetTextFont(32)
112  t.SetTextColor(1)
113  t.SetTextSize(0.03)
114  t.SetTextAlign(12)
115  t.DrawLatex( 3.1, 15.5, 'M.Tokarev, E.Potrebenikova ')
116  t.DrawLatex( 14., 15.5, 'JINR preprint E2-98-64, Dubna, 1998 ')
117  saves[ 't' ] = t
118 
119  pad1 = ROOT.TPad( 'pad1', 'This is pad1', 0.02, 0.02, 0.48, 0.83, 33 )
120  pad2 = ROOT.TPad( 'pad2', 'This is pad2', 0.52, 0.02, 0.98, 0.83, 33 )
121 
122  pad1.Draw()
123  pad2.Draw()
124 
125  saves[ 'pad1' ] = pad1; saves[ 'pad2' ] = pad2
126 
127  #
128  # Cross-section of direct photon production in pp collisions at 500 GeV vs Pt
129  #
130  energ = 63
131  dens = 1.766
132  tgrad = 90.
133  ptmin = 4.
134  ptmax = 24.
135  delp = 2.
136  hz_calc( energ, dens, tgrad, ptmin, ptmax, delp )
137  pad1.cd()
138  pad1.Range( -0.255174, -19.25, 2.29657, -6.75 )
139  pad1.SetLogx()
140  pad1.SetLogy()
141 
142  # create a 2-d histogram to define the range
143  pad1.DrawFrame( 1, 1e-18, 110, 1e-8 )
144  pad1.GetFrame().SetFillColor( 19 )
145  t = ROOT.TLatex()
146  t.SetNDC()
147  t.SetTextFont( 62 )
148  t.SetTextColor( 36 )
149  t.SetTextSize( 0.08 )
150  t.SetTextAlign( 12 )
151  t.DrawLatex( 0.6, 0.85, 'p - p' )
152 
153  t.SetTextSize( 0.05 )
154  t.DrawLatex( 0.6, 0.79, 'Direct #gamma' )
155  t.DrawLatex( 0.6, 0.75, '#theta = 90^{o}' )
156 
157  t.DrawLatex( 0.20, 0.45, 'Ed^{3}#sigma/dq^{3}' )
158  t.DrawLatex( 0.18, 0.40, '(barn/Gev^{2})' )
159 
160  t.SetTextSize( 0.045 )
161  t.SetTextColor( ROOT.kBlue )
162  t.DrawLatex( 0.22, 0.260, '#sqrt{s} = 63(GeV)' )
163  t.SetTextColor( ROOT.kRed )
164  t.DrawLatex( 0.22, 0.205,'#sqrt{s} = 200(GeV)' )
165  t.SetTextColor( 6 )
166  t.DrawLatex( 0.22, 0.15, '#sqrt{s} = 500(GeV)' )
167 
168  t.SetTextSize( 0.05 )
169  t.SetTextColor( 1 )
170  t.DrawLatex( 0.6, 0.06, 'q_{T} (Gev/c)' )
171  saves[ 't2' ] = t # note the label that is used!
172 
173  gr1 = ROOT.TGraph( NLOOP, PT, INVSIG )
174 
175  gr1.SetLineColor( 38 )
176  gr1.SetMarkerColor( ROOT.kBlue )
177  gr1.SetMarkerStyle( 21 )
178  gr1.SetMarkerSize( 1.1 )
179  gr1.Draw( 'LP' )
180  saves[ 'gr1' ] = gr1
181 
182  #
183  # Cross-section of direct photon production in pp collisions at 200 GeV vs Pt
184  #
185 
186  energ = 200
187  dens = 2.25
188  tgrad = 90.
189  ptmin = 4.
190  ptmax = 64.
191  delp = 6.
192  hz_calc( energ, dens, tgrad, ptmin, ptmax, delp )
193 
194  gr2 = ROOT.TGraph( NLOOP, PT, INVSIG )
195  gr2.SetLineColor( 38 )
196  gr2.SetMarkerColor( ROOT.kRed )
197  gr2.SetMarkerStyle( 29 )
198  gr2.SetMarkerSize( 1.5 )
199  gr2.Draw( 'LP' )
200  saves[ 'gr2' ] = gr2
201 
202  #
203  # Cross-section of direct photon production in pp collisions at 500 GeV vs Pt
204  #
205  energ = 500
206  dens = 2.73
207  tgrad = 90.
208  ptmin = 4.
209  ptmax = 104.
210  delp = 10.
211  hz_calc( energ, dens, tgrad, ptmin, ptmax, delp )
212 
213  gr3 = ROOT.TGraph( NLOOP, PT, INVSIG )
214 
215  gr3.SetLineColor( 38 )
216  gr3.SetMarkerColor( 6 )
217  gr3.SetMarkerStyle( 8 )
218  gr3.SetMarkerSize( 1.1 )
219  gr3.Draw( 'LP' )
220  saves[ 'gr3' ] = gr3
221 
222  dum = array( 'f', [0.] )
223  graph = ROOT.TGraph( 1, dum, dum )
224  graph.SetMarkerColor( ROOT.kBlue )
225  graph.SetMarkerStyle( 21 )
226  graph.SetMarkerSize( 1.1 )
227  graph.SetPoint( 0, 1.7, 1.e-16 )
228  graph.Draw( 'LP' )
229  saves[ 'graph' ] = graph
230 
231  graph = ROOT.TGraph( 1, dum, dum )
232  graph.SetMarkerColor( ROOT.kRed )
233  graph.SetMarkerStyle( 29 )
234  graph.SetMarkerSize( 1.5 )
235  graph.SetPoint( 0, 1.7, 2.e-17 )
236  graph.Draw( 'LP' )
237  saves[ 'graph2' ] = graph # note the label that is used!
238 
239  graph = ROOT.TGraph( 1, dum, dum )
240  graph.SetMarkerColor( 6 )
241  graph.SetMarkerStyle( 8 )
242  graph.SetMarkerSize( 1.1 )
243  graph.SetPoint( 0, 1.7, 4.e-18)
244  graph.Draw( 'LP' )
245  saves[ 'graph3' ] = graph # note the label that is used!
246 
247  pad2.cd()
248  pad2.Range( -0.43642, -23.75, 3.92778, -6.25 )
249  pad2.SetLogx()
250  pad2.SetLogy()
251 
252  pad2.DrawFrame( 1, 1e-22, 3100, 1e-8 )
253  pad2.GetFrame().SetFillColor( 19 )
254 
255  gr = ROOT.TGraph( NLOOP, Z, HZ )
256  gr.SetTitle( 'HZ vs Z' )
257  gr.SetFillColor( 19 )
258  gr.SetLineColor( 9 )
259  gr.SetMarkerColor( 50 )
260  gr.SetMarkerStyle( 29 )
261  gr.SetMarkerSize( 1.5 )
262  gr.Draw( 'LP' )
263  saves[ 'gr' ] = gr
264 
265  t = ROOT.TLatex()
266  t.SetNDC()
267  t.SetTextFont( 62 )
268  t.SetTextColor( 36 )
269  t.SetTextSize( 0.08 )
270  t.SetTextAlign( 12 )
271  t.DrawLatex( 0.6, 0.85, 'p - p' )
272 
273  t.SetTextSize( 0.05 )
274  t.DrawLatex( 0.6, 0.79, 'Direct #gamma' )
275  t.DrawLatex( 0.6, 0.75, '#theta = 90^{o}' )
276 
277  t.DrawLatex( 0.70, 0.55, 'H(z)' )
278  t.DrawLatex( 0.68, 0.50, '(barn)' )
279 
280  t.SetTextSize( 0.045 )
281  t.SetTextColor( 46 )
282  t.DrawLatex( 0.20, 0.30, '#sqrt{s}, GeV' )
283  t.DrawLatex( 0.22, 0.26, '63' )
284  t.DrawLatex( 0.22, 0.22, '200' )
285  t.DrawLatex( 0.22, 0.18, '500' )
286 
287  t.SetTextSize( 0.05 )
288  t.SetTextColor( 1 )
289  t.DrawLatex( 0.88, 0.06, 'z' )
290  saves[ 't3' ] = t # note the label that is used!
291 
292  c1.Modified()
293  c1.Update()
294 
295 
296 if __name__ == '__main__': # run if loaded as script
297  zdemo()
Authors
Michael Tokarev, Elena Potrebenikova (JINR Dubna)

Definition in file zdemo.py.