Mitglied der Helmholtz-Gemeinschaft
89
D Meson Production Cross Section
6.0 6.5 7.0 7.5 8.0
p
lab
(GeV/c)
6.0 6.5 7.0 7.5 8.0
p
lab
(GeV/c)
10-3
10-2
10-1
100
σ
tot
(µb)
pp -> D+
D-
FIG. 3: Total reaction cross sections for ¯
pp → D ¯
D as a func-
tion of plab
, based on baryon-exchange (shaded band) and
the quark model (grid). Results obtained in Born approx-
imation are indicated by the dotted (baryon-exchange) and
Baryon Exchange Model
Quark Model
p
lab
(GeV/c)
6.0 6.5 7.0 7.5 8.0
p
lab
(GeV/c)
10-3
10-2
10-1
100
σ
tot
(µb)
pp -> D+
D-
3: Total reaction cross sections for ¯
pp → D ¯
D as a func-
of plab
, based on baryon-exchange (shaded band) and
uark model (grid). Results obtained in Born approx-
on are indicated by the dotted (baryon-exchange) and
dotted (quark model) lines, respectively.
lab
6.0 6.5 7.0 7.5 8.0
p
lab
(GeV/c)
10-3
10-2
10-1
100
σ
tot
(µb)
pp -> D+
D-
3: Total reaction cross sections for ¯
pp → D ¯
D as a func-
of plab
, based on baryon-exchange (shaded band) and
uark model (grid). Results obtained in Born approx-
on are indicated by the dotted (baryon-exchange) and
dotted (quark model) lines, respectively.
J. Haidenbauer, G. Krein; Production of charmed pseudoscalar mesons
in antiproton-proton annihilation; arXiv:1404.4174 [hep-ph] (04-2014)
from Foley et al. [43], Berglund et al. [47], Russ et al. [48],
Λ,Σ,
Σ(1385)
K K
N N
✉ ✉ ↔
Λc
,Σc
,
Σc
(2520)
D D
N N
✉ ✉
FIG. 2: Transition potential for ¯
NN → D ¯
D (right) and
¯
NN → ¯
KK (left), respectively.
D ¯
D, ¯
NN = V D ¯
D, ¯
NN
+ V D ¯
D, ¯
NN G ¯
NN T ¯
NN, ¯
NN , (5)
he ¯
NN potential described in Sect. II.
Eq. (5) implies that the ¯
NN → D ¯
D transition
s effectively evaluated in a DWBA.
with inclusion of ISI effects are presented as
ig. 3 because we consider several variants of
otential as discussed in the previous section.
s that the results change drastically once the
ded in the calculation. The cross sections for
trongly reduced while at the same time those
are enhanced. Indeed now both D ¯
D channels
d at a comparable rate. In fact, the predicted
n for D+D− appears to be even somewhat
the one for D0 ¯
D0.
the reduction in the D0 ¯
D0 case is in line
arable effects observed in the previous stud-
annihilation processes [23, 25–27], as men-
ve, the enhancement seen for D+D− may be
6.0 6.5 7.0 7.
p
lab
(GeV/c)
10-3
10-2
10-1
100
σ
tot
(µb)
FIG. 3: Total reaction cross sections for ¯
pp
tion of plab
, based on baryon-exchange (s
the quark model (grid). Results obtained
imation are indicated by the dotted (bary
dash-dotted (quark model) lines, respective
Q Q
q q q q
FIG. 4: Microscopic quark-model mechanism for the
tion potential: annihilation of two pairs of light quark
u¯
u, d ¯
d, and creation of a pair of heavier quarks, Q ¯
Q =
(¯
cc) is created – see Fig. 4. We base our study
model of Kohno and Weise (KW) [28] for the ¯
pp
reaction; we replace parameters corresponding
s−quark and K−meson of that model by those
c−quark and D−meson. The quark-model ¯
NN
transition potential V ¯
NN→D ¯
D
Q
(t) can be written
V ¯
NN→D ¯
D
Q
(t) = χ†
¯
N
[h1
(t) σ · p + h2
(t) σ · p] χN
cutoff mass below.
us now focus on the effects of the initial state inter-
Those effects are included by solving the formal
d-channel equations
T ¯
NN, ¯
NN = V ¯
NN, ¯
NN
+ V ¯
NN, ¯
NN G ¯
NN T ¯
NN, ¯
NN , (4)
T D ¯
D, ¯
NN = V D ¯
D, ¯
NN
+ V D ¯
D, ¯
NN G ¯
NN T ¯
NN, ¯
NN , (5)
ng the ¯
NN potential described in Sect. II.
rse, Eq. (5) implies that the ¯
NN → D ¯
D transition
ude is effectively evaluated in a DWBA.
ults with inclusion of ISI effects are presented as
in Fig. 3 because we consider several variants of
N potential as discussed in the previous section.
bvious that the results change drastically once the
ncluded in the calculation. The cross sections for
are strongly reduced while at the same time those
+D− are enhanced. Indeed now both D ¯
D channels
oduced at a comparable rate. In fact, the predicted
section for D+D− appears to be even somewhat
than the one for D0 ¯
D0.
ereas the reduction in the D0 ¯
D0 case is in line
omparable effects observed in the previous stud-
¯
NN annihilation processes [23, 25–27], as men-
above, the enhancement seen for D+D− may be
6.0 6.5 7.0 7.5
p
lab
(GeV/c)
10-3
10-2
6.0 6.5 7.0 7.5
p
lab
(GeV/c)
10-3
10-2
10-1
100
σ
tot
(µb)
p
FIG. 3: Total reaction cross sections for ¯
pp
tion of plab
, based on baryon-exchange (sh
the quark model (grid). Results obtained
imation are indicated by the dotted (baryo
dash-dotted (quark model) lines, respectivel
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