[u/mrichter/AliRoot.git] / PDF / spdf / grvgaho.F

*
* $Id$
*
* $Log$
* Revision 1.4  2000/09/18 10:02:35  hristov
* Makefile added to PDF8
*
* Revision 1.1.1.2  1996/10/30 08:28:40  cernlib
* Version 7.04
*
* Revision 1.1.1.1  1996/04/12 15:29:23  plothow
* Version 7.01
*
*
#include "pdf/pilot.h"
       SUBROUTINE GRVGAHO (ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL)
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*                                                                 *
*      G R V - P H O T O N - P A R A M E T R I Z A T I O N S      *
*                                                                 *
*                 FOR A DETAILED EXPLANATION SEE :                *
*              M. GLUECK, E.REYA, A.VOGT: DO-TH 91/31             *
*                                                                 *
*    THE OUTPUT IS ALWAYS   1./ ALPHA(EM) * X * PARTON DENSITY    *
*    output modified by HPB to be always    X * PARTON DENSITY    *
*                                                                 *
*   THE PARAMETRIZATIONS ARE FITTED TO THE PARTON DISTRIBUTIONS   *
*   FOR Q ** 2 BETWEEN MU ** 2 (=  0.25 / 0.30  GEV ** 2  IN LO   *
*   / HO) AND  1.E6 GEV ** 2  AND FOR X BETWEEN  1.E-5  AND  1.   *
*                                                                 *
*              HEAVY QUARK THRESHOLDS  Q(H) = M(H) :              *
*         M(C)  =  1.5,  M(B)  =  4.5,  M(T)  =  100  GEV         *
*                                                                 *
*      CORRESPONDING LAMBDA(F) VALUES FOR F ACTIVE FLAVOURS :     *
*      LO :   LAMBDA(3)  =  0.232,   LAMBDA(4)  =  0.200,         *
*             LAMBDA(5)  =  0.153,   LAMBDA(6)  =  0.082  GEV     *
*      HO :   LAMBDA(3)  =  0.248,   LAMBDA(4)  =  0.200,         *
*             LAMBDA(5)  =  0.131,   LAMBDA(6)  =  0.053  GEV     *
*                                                                 *
*      HO DISTRIBUTIONS REFER TO THE DIS(GAMMA) SCHEME, SEE :     *
*              M. GLUECK, E.REYA, A.VOGT: DO-TH 91/26             *
*                                                                 *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
C
       IMPLICIT REAL (A - Y)
#if defined(CERNLIB_DOUBLE)
      DOUBLE PRECISION
#endif
#if defined(CERNLIB_SINGLE)
      REAL
#endif
     +        ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL
       DATA ALPHEM/7.29927D-3/
       REAL  X, Q
       X = ZX
       Q = ZQ
       MU2  = 0.3
       LAM2 = 0.248 * 0.248
       Q2 = Q*Q
       S  = ALOG (ALOG(Q2/LAM2) / ALOG(MU2/LAM2))
       SS = SQRT (S)
       S2 = S * S
C...X * U = X * UBAR :
       AL =  0.583
       BE =  0.688
       AK =  0.449 - 0.025 * S  - 0.071 * S2
       BK =  5.060 - 1.116 * SS
       AG =  0.103
       BG =  0.319 + 0.422 * S
       C  =  1.508 + 4.792 * S  - 1.963 * S2
       D  =  1.075 + 0.222 * SS - 0.193 * S2
       E  =  4.147 + 1.131 * S
       ES =  1.661 + 0.874 * S
       UH =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
       ZUV = UH * ALPHEM
       ZUB = ZUV
C...X * D = X * DBAR :
       AL =  0.591
       BE =  0.698
       AK =  0.442 - 0.132 * S  - 0.058 * S2
       BK =  5.437 - 1.916 * SS
       AG =  0.099
       BG =  0.311 - 0.059 * S
       C  =  0.800 + 0.078 * S  - 0.100 * S2
       D  =  0.862 + 0.294 * SS - 0.184 * S2
       E  =  4.202 + 1.352 * S
       ES =  1.841 + 0.990 * S
       DH  =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
       ZDV = DH * ALPHEM
       ZDB = ZDV
C...X * G :
       AL =  1.161
       BE =  1.591
       AK =  0.530 - 0.742 * SS + 0.025 * S2
       BK =  5.662
       AG =  0.533 - 0.281 * SS + 0.218 * S2
       BG =  0.025 - 0.518 * S  + 0.156 * S2
       C  = -0.282              + 0.209 * S2
       D  =  0.107 + 1.058 * S  - 0.218 * S2
       E  =   0.0  + 2.704 * S
       ES =  3.071 - 0.378 * S
       GH =  GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
       ZGL = GH * ALPHEM
C...X * S = X * SBAR :
       SF =   0.0
       AL =  0.635
       BE =  0.456
       AK =  1.770 - 0.735 * SS - 0.079 * S2
       BK =  3.832
       AG =  0.084 - 0.023 * S
       BG =  0.136
       C  =  2.119 - 0.942 * S  + 0.063 * S2
       D  =  1.271 + 0.076 * S  - 0.190 * S2
       E  =  4.604 + 0.737 * S
       ES =  1.641 + 0.976 * S
       SH =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
       ZSB = SH * ALPHEM
C...X * C = X * CBAR :
       SF =  0.820
       AL =  0.926
       BE =  0.152
       AK =  1.142 - 0.175 * S
       BK =  3.276
       AG =  0.504 + 0.317 * S
       BG = -0.433
       C  =  3.334
       D  =  0.398 + 0.326 * S  - 0.107 * S2
       E  =  5.493 + 0.408 * S
       ES =  2.426 + 1.277 * S
       CH =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
       ZCB = CH * ALPHEM
C...X * B = X * BBAR :
       SF =  1.297
       AL =  0.969
       BE =  0.266
       AK =  1.953 - 0.391 * S
       BK =  1.657 - 0.161 * S
       AG =  1.076 + 0.034 * S
       BG = -2.015
       C  =  1.662
       D  =  0.353 + 0.016 * S
       E  =  5.713 + 0.249 * S
       ES =  3.456 + 0.673 * S
       BH =  GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
       ZBB = BH * ALPHEM
c
       RETURN
       END
Commit	Line	Data
21886bb6	1	*
	2	* $Id$
	3	*
	4	* $Log$
7ef50f50	5	* Revision 1.4 2000/09/18 10:02:35 hristov
	6	* Makefile added to PDF8
	7	*
21886bb6	8	* Revision 1.1.1.2 1996/10/30 08:28:40 cernlib
	9	* Version 7.04
	10	*
	11	* Revision 1.1.1.1 1996/04/12 15:29:23 plothow
	12	* Version 7.01
	13	*
	14	*
	15	#include "pdf/pilot.h"
	16	SUBROUTINE GRVGAHO (ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL)
	17	* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
	18	* *
	19	* G R V - P H O T O N - P A R A M E T R I Z A T I O N S *
	20	* *
	21	* FOR A DETAILED EXPLANATION SEE : *
	22	* M. GLUECK, E.REYA, A.VOGT: DO-TH 91/31 *
	23	* *
	24	* THE OUTPUT IS ALWAYS 1./ ALPHA(EM) * X * PARTON DENSITY *
	25	* output modified by HPB to be always X * PARTON DENSITY *
	26	* *
	27	* THE PARAMETRIZATIONS ARE FITTED TO THE PARTON DISTRIBUTIONS *
	28	* FOR Q 2 BETWEEN MU 2 (= 0.25 / 0.30 GEV ** 2 IN LO *
	29	* / HO) AND 1.E6 GEV ** 2 AND FOR X BETWEEN 1.E-5 AND 1. *
	30	* *
	31	* HEAVY QUARK THRESHOLDS Q(H) = M(H) : *
	32	* M(C) = 1.5, M(B) = 4.5, M(T) = 100 GEV *
	33	* *
	34	* CORRESPONDING LAMBDA(F) VALUES FOR F ACTIVE FLAVOURS : *
	35	* LO : LAMBDA(3) = 0.232, LAMBDA(4) = 0.200, *
	36	* LAMBDA(5) = 0.153, LAMBDA(6) = 0.082 GEV *
	37	* HO : LAMBDA(3) = 0.248, LAMBDA(4) = 0.200, *
	38	* LAMBDA(5) = 0.131, LAMBDA(6) = 0.053 GEV *
	39	* *
	40	* HO DISTRIBUTIONS REFER TO THE DIS(GAMMA) SCHEME, SEE : *
	41	* M. GLUECK, E.REYA, A.VOGT: DO-TH 91/26 *
	42	* *
	43	* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
	44	C
	45	IMPLICIT REAL (A - Y)
7ef50f50	46	#if defined(CERNLIB_DOUBLE)
	47	DOUBLE PRECISION
	48	#endif
	49	#if defined(CERNLIB_SINGLE)
	50	REAL
	51	#endif
21886bb6	52	+ ZX,ZQ,ZUV,ZDV,ZUB,ZDB,ZSB,ZCB,ZBB,ZGL
	53	DATA ALPHEM/7.29927D-3/
	54	REAL X, Q
	55	X = ZX
	56	Q = ZQ
	57	MU2 = 0.3
	58	LAM2 = 0.248 * 0.248
	59	Q2 = Q*Q
	60	S = ALOG (ALOG(Q2/LAM2) / ALOG(MU2/LAM2))
	61	SS = SQRT (S)
	62	S2 = S * S
	63	C...X * U = X * UBAR :
	64	AL = 0.583
	65	BE = 0.688
	66	AK = 0.449 - 0.025 * S - 0.071 * S2
	67	BK = 5.060 - 1.116 * SS
	68	AG = 0.103
	69	BG = 0.319 + 0.422 * S
	70	C = 1.508 + 4.792 * S - 1.963 * S2
	71	D = 1.075 + 0.222 * SS - 0.193 * S2
	72	E = 4.147 + 1.131 * S
	73	ES = 1.661 + 0.874 * S
	74	UH = GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
	75	ZUV = UH * ALPHEM
	76	ZUB = ZUV
	77	C...X * D = X * DBAR :
	78	AL = 0.591
	79	BE = 0.698
	80	AK = 0.442 - 0.132 * S - 0.058 * S2
	81	BK = 5.437 - 1.916 * SS
	82	AG = 0.099
	83	BG = 0.311 - 0.059 * S
	84	C = 0.800 + 0.078 * S - 0.100 * S2
	85	D = 0.862 + 0.294 * SS - 0.184 * S2
	86	E = 4.202 + 1.352 * S
	87	ES = 1.841 + 0.990 * S
	88	DH = GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
	89	ZDV = DH * ALPHEM
	90	ZDB = ZDV
	91	C...X * G :
	92	AL = 1.161
	93	BE = 1.591
	94	AK = 0.530 - 0.742 * SS + 0.025 * S2
	95	BK = 5.662
	96	AG = 0.533 - 0.281 * SS + 0.218 * S2
	97	BG = 0.025 - 0.518 * S + 0.156 * S2
	98	C = -0.282 + 0.209 * S2
	99	D = 0.107 + 1.058 * S - 0.218 * S2
	100	E = 0.0 + 2.704 * S
	101	ES = 3.071 - 0.378 * S
	102	GH = GRVGF (X, S, AL, BE, AK, BK, AG, BG, C, D, E, ES)
	103	ZGL = GH * ALPHEM
	104	C...X * S = X * SBAR :
	105	SF = 0.0
	106	AL = 0.635
	107	BE = 0.456
	108	AK = 1.770 - 0.735 * SS - 0.079 * S2
	109	BK = 3.832
	110	AG = 0.084 - 0.023 * S
	111	BG = 0.136
	112	C = 2.119 - 0.942 * S + 0.063 * S2
	113	D = 1.271 + 0.076 * S - 0.190 * S2
	114	E = 4.604 + 0.737 * S
	115	ES = 1.641 + 0.976 * S
116	SH = GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
117	ZSB = SH * ALPHEM
118	C...X * C = X * CBAR :
119	SF = 0.820
120	AL = 0.926
121	BE = 0.152
122	AK = 1.142 - 0.175 * S
123	BK = 3.276
124	AG = 0.504 + 0.317 * S
125	BG = -0.433
126	C = 3.334
127	D = 0.398 + 0.326 * S - 0.107 * S2
128	E = 5.493 + 0.408 * S
129	ES = 2.426 + 1.277 * S
130	CH = GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
131	ZCB = CH * ALPHEM
132	C...X * B = X * BBAR :
133	SF = 1.297
134	AL = 0.969
135	BE = 0.266
136	AK = 1.953 - 0.391 * S
137	BK = 1.657 - 0.161 * S
138	AG = 1.076 + 0.034 * S
139	BG = -2.015
140	C = 1.662
141	D = 0.353 + 0.016 * S
142	E = 5.713 + 0.249 * S
143	ES = 3.456 + 0.673 * S
144	BH = GRVGFS (X, S, SF, AL, BE, AK, BK, AG, BG, C, D, E, ES)
145	ZBB = BH * ALPHEM
146	c
147	RETURN
148	END