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12 Parabolic Cylinder FunctionsProperties

§12.5 Integral Representations


§12.5(i) Integrals Along the Real Line

12.5.1 U(a,z)=e-14z2Γ(12+a)0ta-12e-12t2-ztdt,
a>-12 ,
12.5.2 U(a,z)=ze-14z2Γ(14+12a)0t12a-34e-t(z2+2t)-12a-34dt,
|phz|<12π, a>-12 ,
12.5.3 U(a,z)=e-14z2Γ(34+12a)0t12a-14e-t(z2+2t)-12a-14dt,
|phz|<12π, a>-32 ,
12.5.4 U(a,z)=2πe14z20t-a-12e-12t2cos(zt+(12a+14)π)dt,
a<12 .

§12.5(ii) Contour Integrals

The following integrals correspond to those of §12.5(i).

12.5.5 U(a,z)=Γ(12-a)2πie-14z2-(0+)ezt-12t2ta-12dt,
a12,32,52,, -π<pht<π.

Restrictions on a are not needed in the following two representations:

12.5.6 U(a,z)=e14z2i2πc-ic+ie-zt+12t2t-a-12dt,
-12π<pht<12π, c>0 ,
12.5.7 V(a,z)=e-14z22π(-ic--ic++ic-ic+)ezt-12t2ta-12dt,
-π<pht<π, c>0.

For proofs and further results see Miller (1955, §4) and Whittaker (1902).

§12.5(iii) Mellin–Barnes Integrals

12.5.8 U(a,z) =e-14z2z-a-122πiΓ(12+a)-iiΓ(t)Γ(12+a-2t)2tz2tdt,
a-12,-32,-52,, |phz|<34π,
where the contour separates the poles of Γ(t) from those of Γ(12+a-2t).
12.5.9 V(a,z) =2πe14z2za-122πiΓ(12-a)-iiΓ(t)Γ(12-a-2t)2tz2tcos(πt)dt,
a12,32,52,, |phz|<14π,

where the contour separates the poles of Γ(t) from those of Γ(12-a-2t).

§12.5(iv) Compendia

For further collections of integral representations see Apelblat (1983, pp. 427-436), Erdélyi et al. (1953b, v. 2, pp. 119–120), Erdélyi et al. (1954a, pp. 289–291 and 362), Gradshteyn and Ryzhik (2000, §§9.24–9.25), Magnus et al. (1966, pp. 328–330), Oberhettinger (1974, pp. 251–252), and Oberhettinger and Badii (1973, pp. 378–384).